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Background: Digital therapeutics (DTx) are therapeutic interventions driven by software and directly provided to patients, allowing them to manage their health with ease in any setting. A growing interest in DTx has spurred a discussion concerning their reimbursement pathways. However, DTx are still at a premature stage, with insufficient evidence on effectiveness, efficiency, and safety. Currently, although industries desire to quickly enter the market, especially by getting their products reimbursed by the National Health Insurance (NHI) fund, the NHI is cautious about DTx due to their uncertainties. Thus, public discussion and social consensus are crucial in deciding whether to reimburse DTx by the NHI fund., Objective: This study examined multiple stakeholders' awareness and attitudes toward DTx and perceptions of regulatory pathways for adopting DTx., Methods: In-depth interviews were conducted with 11 stakeholders in South Korea (industry: n=4, health care: n=3, academia: n=2, and consumer: n=2) using semistructured guidelines. They were purposively sampled to identify individuals with expertise in DTx and NHI policies. The interviews were conducted either in person or via a videoconference for 45-70 minutes. Qualitative data were analyzed using directed content analysis, which uses interview guidelines as an analytical framework., Results: Findings were divided into three categories: (1) awareness and attitude toward DTx, (2) perception of whether DTx are worth entering the market and being reimbursed by the NHI fund, and (3) perception of how to enter the market and how to reimburse DTx by the NHI fund if they are worth it. Although consumer stakeholders were not familiar with the basic concept of DTx, the other stakeholders understood it thoroughly. However, all participants showed positive attitudes and acceptance of DTx. Most of them responded that DTx are worth entering the market, but they could not reach an agreement on the pathways for DTx to enter the market. Although participants were in favor of the reimbursement of DTx in principle, they responded that a conservative approach is required due to insufficient clinical evidence for DTx., Conclusions: We found that stakeholders in South Korea had positive attitudes toward DTx, perceived them as worth using, and agreed to allow them to enter the market. The main issue was not the problem of the technology itself but the difference in opinion as to the pathways for reimbursement. Therefore, this study concluded that the NHI fund, which is operated very conservatively, is insufficient to quickly adopt and implement DTx. Various reimbursement methods, including tax-based financing, raising innovation funds for new technologies, and pilot studies using the NHI fund, should be used to rapidly generate clinical evidence and reduce the uncertainties of DTx to secure a stable market., (© Boram Sim, Jin Han Ju, Byungsoo Kim, Jin Yong Lee. Originally published in JMIR mHealth and uHealth (https://mhealth.jmir.org).)

With the invasion of green tides and the increase of urban green areas worldwide, multimillion tons of Enteromorpha need to be reutilized. In this study, Enteromorpha prolifera powder is considered a promising biomass resource for the production of commercial chemical products production. Ilamycins, novel cyclic heptapeptides with significant anti-TB activities, are isolated from Streptomyces atratus SCSIO ZH16, a deep-sea-derived strain. Using EP powder as a nitrogen source, the production of ilamycins reached 709.97 mg/L through optimization of the nitrogen source using the engineered strain S. atratus SCSIO ZH16 ΔR. After mutant strain constructions and tests, strain S. atratus SCSIO ZH16 ΔR::bldD EP powder achieved a higher production titer of ilamycins. Furthermore, the production titer of ilamycins and ilamycin E reached 1561.77 mg/L and 745.44 mg/L, respectively, in a 5 L bioreactor. This study suggests that E. prolifera is a promising and eco-friendly nitrogen source for the production of ilamycins., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Objective: This study determined the impact of demographic factors, clinical manifestations, disease activity, and serological tests at baseline on future SLE development in Sjögren's syndrome (SS) patients., Methods: This retrospective study assessed 1,082 SS patients without other autoimmune diseases at baseline who visited our hospital between January 2012 and March 2021. We analyzed demographic features, extra-glandular manifestations (EGMs), clinical indices, and laboratory values at baseline between the two groups divided per future SLE development (SS/SLE group vs SS group). The probability and predictors of SLE development in SS patients were estimated using the Kaplan-Meier method and Cox proportional hazards models., Results: The median follow-up duration was 1083.5 days. Forty-nine patients (4.5%) developed SLE that met the 2012 Systemic Lupus International Collaborating Clinics or 2019 EULAR/ACR classification criteria. The baseline EULAR SS disease activity index (ESSDAI) score was significantly higher in the SS/SLE group ( p < .001). The SS/SLE group had more lymphadenopathy and renal involvement ( p = .015 and p = .017, respectively). Shorter SS disease duration (<3 years) (hazard ratio [HR] = 2.12, p = .0328), high ESSDAI (HR = 8.24, p < .0001), leukopenia (HR = 4.17, p = .0005), thrombocytopenia (HR = 3.38, p = .0059), hypocomplementemia (HR = 29.06, p <.0001), and positive for anti-dsDNA (HR = 13.70, p < .0001), anti-ribonucleoprotein (RNP) (HR = 3.82, p = .0027), and anti-ribosomal P (HR = 6.70, p = .0002) at baseline were SLE development predictors in SS patients., Conclusion: Shorter disease duration and higher disease activity of SS at baseline may be risk factors for future SLE development. Serologic predictors of SLE development are hypocomplementemia, leukopenia, thrombocytopenia, and positivity for anti-dsDNA, anti-RNP, and anti-ribosomal P antibodies. If the above factors are observed, close monitoring will be necessary during the follow-up period, considering the possibility of future SLE development., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: To investigate clinical effects of anterolateral thigh flap with blood supply source of medial femoral perforator in repairing the wounds on extremities. Methods: A retrospective observational study was conducted. From October 2018 to June 2021, Suzhou Ruihua Orthopedic Hospital admitted 12 patients (11 males and 1 female, aged 24-64 years) who met the inclusion criteria, and did not have the lateral circumflex femoral artery during anterolateral thigh flap resection, or changed to medial femoral perforator as a source of blood supply due to small perforator to repair the wound with flap transplantation. The wounds were on the upper limbs in 7 cases and on the lower limbs in 5 cases. The wound area after debridement was 8.0 cm×5.0 cm-24.0 cm×6.5 cm, and the applied flap area was 9 cm×6 cm-25 cm×7 cm. During transplantation, the perforating branch or source artery of the flap was anastomosed end to end with the vascular pedicle of the recipient area. Subcutaneous beauty suture was performed on all the donor wounds. After operation, the survival of the flap and vascular crisis were observed; and the wound healing at the donor site was observed. During follow-up, the texture of the flap and complications at the donor site were observed. At the last follow-up, the effect of flap repair was evaluated by using the modified self-made comprehensive efficacy rating table. Results: After operation, all the flaps of patients survived without vascular crisis; the wounds in the donor site healed smoothly. During follow-up of 6 to 26 months, the flaps had good texture; only linear scars remained in the donor area without scar contracture, pain or other discomfort. At the last follow-up, the total score of flap repair effect of 12 patients was 75-95, with an average of 87, of which 5 cases were rated as excellent, 6 cases as good, and 1 case as fair, and the proportion of excellent and good patients was 11/12. Conclusions: The application of anterolateral thigh flap with blood supply from the medial femoral perforator to repair wounds on extremities is an alternative method for the vascular variations such as no descending branch, oblique branch, or small perforator of the lateral circumflex femoral artery during the resection of the anterolateral thigh flap. This operation has the advantages of simple operation, small trauma, and others, which effectively ensures the smooth operation.

Cartilage is mainly composed of chondrocytes and the extracellular matrix (ECM), which transmits important biochemical and biomechanical signals necessary for differentiation and homeostasis. Human articular cartilage has a low ability for regeneration because it lacks blood vessels, nerves, and lymphatic vessels. Currently, cell therapeutics, including stem cells, provide a promising strategy for cartilage regeneration and treatment; however, there are various hurdles to overcome, such as immune rejection and teratoma formation. In this study, we assessed the applicability of stem cell-derived chondrocyte ECM for cartilage regeneration. Human induced pluripotent stem cell (hiPSC)-derived chondrocytes (iChondrocytes) were differentiated, and decellularized ECM (dECM) was successfully isolated from cultured chondrocytes. Isolated dECM enhanced the in vitro chondrogenesis of iPSCs when recellularized. Implanted dECM also restored osteochondral defects in a rat osteoarthritis model. A possible association with the glycogen synthase kinase-3 beta (GSK3β) pathway demonstrated the fate-determining importance of dECM in regulating cell differentiation. Collectively, we suggest the prochondrogenic effect of hiPSC-derived cartilage-like dECM and offer a promising approach of a noncellular therapeutic for articular cartilage reconstruction without cell transplantation. STATEMENT OF SIGNIFICANCE: Human articular cartilage has low ability for regeneration and cell culture-based therapeutics could aid cartilage regeneration. Yet, the applicability of human induced pluripotent stem cell-derived chondrocyte (iChondrocyte) extracellular matrix (ECM) has not been elucidated. Therefore, we first differentiated iChondrocytes and isolated the secreted ECM by decellularization. Recellularization was performed to confirm the pro-chondrogenic effect of the decellularized ECM (dECM). In addition, we confirmed the possibility of cartilage repair by transplanting the dECM into the cartilage defect in osteochondral defect rat knee joint. We believe that our proof-of-concept study will serve as a basis for investigating the potential of dECM obtained from iPSC-derived differentiated cells as a non-cellular resource for tissue regeneration and other future applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

This study aimed to determine the policy implications for drug management by identifying the prescription trends of potentially inappropriate medications (PIMs) in older outpatients. Considering the Drug Utilization Review and Korean version of the standards for PIMs based on the Beers Criteria, 141 ingredients were selected that spanned over 7 years of health insurance claims data analysis. During the study period, the number of patients and claims related to PIMs increased. Although the number of health insurance claims decreased in 2020 owing to coronavirus disease (COVID-19), it increased again in 2021. Tamsulosin was the most frequently prescribed drug for male patients, followed by alprazolam and zolpidem. For female patients, eperisone was the most frequently prescribed drug, followed by alprazolam, zolpidem, and etizolam. In Korea, health insurance claims for PIMs decreased in 2020 owing to the COVID-19 pandemic. However, an overall increasing trend was observed from 2015 to 2021. Moreover, during this period, the prescription trend of benzodiazepine-type drugs and zolpidem increased in both male and female patients. Therefore, management policies regarding PIMs and drug ingredients, such as benzodiazepines and zolpidem, are required., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: To investigate the effects of tibial second toe free flap bridged with blood flow and nerve in the treatment of severe flexion contracture of the proximal interphalangeal joint. Methods: A retrospective observational study was conducted. From March 2013 to October 2019, 9 patients with severe flexion contracture (type Ⅲ) of the proximal interphalangeal joint after trauma operation, conforming to the inclusion criteria, were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 5 males and 4 females, aged from 17 to 62 years. After the contracture tissue affecting the extension of the proximal interphalangeal joint was cut off, and the scar tissue was resected, the size of the volar wound near the proximal interphalangeal joint in extended position was 2.0 cm×1.0 cm-2.5 cm×1.5 cm, with the length of proper digital artery and nerve defect being 1.0-1.5 cm. A free flap of the same size as the wound was cut from the tibial side of the second toe and transplanted to repair the wound, and the defective proper digital artery and nerve was repaired by bridging with the tibial proper plantar digital artery and nerve of about 1.5 cm in length. The full-thickness skin graft was taken from the proximal tibial side of the lower leg to repair the wound at flap donor site. The wound at skin graft donor site was sutured directly. The survival of flap and skin graft was observed after operation. The patients were followed up, and at the last follow-up, the recovery of the affected finger and the second toe, including the donor and recipient areas were observed, the two-point discrimination distances of the flap repaired site and the pulp of the affected finger were observed and measured at the same time, the blood flow patency of bridged vessel of the affected finger was examined by Allen test, and the function of the proximal interphalangeal joint of the affected finger was evaluated according to Chinese Medical Association's standard for the range of motion of proximal interphalangeal joint. Results: The flaps and skin grafts survived smoothly after operation. The follow-up after operation lasted for 5 to 22 months, with a mean of 10 months. At the last follow-up, the flap repaired site had good shape, good color and texture, with the two-point discrimination distance being 9-12 mm, and the two-point discrimination distance of the pulp of the affected finger was 6-10 mm; the Allen test results of the affected fingers were all negative (i.e., the bridged vessels had good blood flow patency), with no recurrence of flexion contracture, and the function of the proximal interphalangeal joint was evaluated as excellent; the skin graft area of the second toe was not ruptured but was a little pigmented, and the flexion and extension activities of toe were good. Conclusions: The tibial second toe free flap bridged with blood flow and nerve has reliable therapeutic effect in the treatment of severe flexion contracture of the proximal interphalangeal joint, and the color and texture of the flap repaired area are good. Bridging to repair the severely contracted proper digital artery and nerve is beneficial to improve the blood supply of the finger body and rebuild the sensation.

Objective: To investigate the therapeutic efficacy of bilobated superficial peroneal artery perforator flap in repairing two adjacent wounds of the fingers. Methods: A retrospective observational study was conducted. From January 2021 to January 2022, 15 patients with two adjacent wounds of the fingers who met the inclusion criteria were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 10 males and 5 females, aged 25 to 51 years. The area of single wound after debridement was from 2.5 cm×2.0 cm to 7.5 cm×2.5 cm. All the wounds were repaired by the bilobated superficial peroneal artery perforator flap from the lower leg. The single lobe area of bilobated flap was from 3.0 cm×2.0 cm to 8.0 cm×3.0 cm. The wounds in all the donor sites were sutured directly. During the operation, the number of resected flaps, the number and type of carried perforators were recorded, and the calibers of perforator and superficial peroneal artery and the length of vascular pedicle were measured. The survival of flap and the wound healing in the donor and recipient sites were recorded after operation. The recovery of donor and recipient sites were recorded during follow-up. At the last follow-up, the repair effect of flap was evaluated by the comprehensive evaluation scale, and the sensory function of flap was evaluated by the sensory function evaluation standard of British Medical Research Association. Results: During the operation, 15 bilobated flaps were successfully resected, carrying 36 superficial peroneal artery perforators, all of which were septocutaneous perforators with the caliber of 0.2-0.8 mm. The caliber of superficial peroneal artery was 0.4-1.1 mm and the length of vascular pedicle was 3-8 cm. After operation, all the flaps survived with no vascular crisis occurred, and the wounds in donor and recipient sites healed well. During the follow-up of 6 to 12 months, the color and texture of flaps were similar to those of normal tissue in the hand and the appearance of flap was good in 10 cases; the other 5 cases underwent the stage Ⅱ flap thinning and plastic surgery 6 months after operation due to the bloated appearance of flaps. There was only linear scar in the donor site of lower leg, with no obvious scar hyperplasia or pigmentation, and there was no obvious adverse effect on the sensation or motor function of the distal limbs in the donor area. At the last follow-up, the repair effect of flap of 15 patients was excellent in 11 cases and good in 4 cases, and the sensory function of the flap was evaluated as grade S 2 in all cases. Conclusions: The bilobated superficial peroneal artery perforator flap has high proportion of septocutaneous perforator, and the blood supply is sufficient and reliable. Using this flap to repair two adjacent wounds of the fingers causes minimal damage to the donor area, only one group of blood vessels is needed to be anastomosed to repair two wounds, the difficulty of microoperation is reduced, and good flap repair effect and sensory function can be obtained.

Background: Chemical fertilizers have greatly contributed to the development of agriculture, but alternative fertilizers are needed for the sustainable development of agriculture. 2,3-butanediol (2,3-BDO) is a promising biological plant growth promoter., Results: In this study, we attempted to develop an effective strategy for the biological production of highly pure R,R-2,3-butanediol (R,R-2,3-BDO) by Paenibacillus polymyxa fermentation. First, gamma-ray mutagenesis was performed to obtain P. polymyxa MDBDO, a strain that grew faster than the parent strain and had high production of R,R-2,3-BDO. The activities of R,R-2,3-butanediol dehydrogenase and diacetyl reductase of the mutant strain were increased by 33% and decreased by 60%, respectively. In addition, it was confirmed that the carbon source depletion of the fermentation broth affects the purity of R,R-2,3-BDO through batch fermentation. Fed-batch fermentation using controlled carbon feeding led to production of 77.3 g/L of R,R-2,3-BDO with high optical purity (> 99% of C 4 products) at 48 h. Additionally, fed-batch culture using corn steep liquor as an alternative nitrogen source led to production of 70.3 g/L of R,R-2,3-BDO at 60 h. The fed-batch fermentation broth of P. polymyxa MDBDO, which contained highly pure R,R-2,3-BDO, significantly stimulated the growth of soybean and strawberry seedlings., Conclusions: This study suggests that P. polymyxa MDBDO has potential for use in biological plant growth promoting agent applications. In addition, our fermentation strategy demonstrated that high-purity R,R-2,3-BDO can be produced at high concentrations using P. polymyxa., (© 2023. The Author(s).)

Objective: To investigate the surgical methods and clinical effects of free superficial peroneal artery perforator flap in repairing small and medium-sized thermal crush injury wounds in the hand. Methods: A retrospective observational study was conducted. From August 2018 to December 2021, 12 patients (19 wounds) with small and medium-sized thermal crush injury in the hand who met the inclusion criteria were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 5 males and 7 females, aged from 30 to 54 years. The area of the wound was from 2.5 cm×2.0 cm to 14.0 cm×3.5 cm, and all the wounds were repaired by using free superficial peroneal artery perforator flaps from lower leg on one side (including single flap, multiple flaps, and multiple flaps with one pedicle resected from the same donor site). The area of the flap was from 3.5 cm×3.0 cm to 16.0 cm×4.0 cm. The wound in the donor site was sutured directly. The vascular crisis and survival of the flap were observed after operation. The texture, appearance, color, hyperpigmentation, sensation, and two-point discrimination of the flap repaired area were followed up, as well as the hyperplasia of scar and pain condition in the donor and recipient sites. At the last follow-up, the curative effect of flap repair was evaluated by the comprehensive evaluation scale, and the extension and flexion functions of the reserved digital joint were evaluated by the total active movement systematic evaluation method recommended by American Academy for Surgery of Hand. Results: One flap developed arterial crisis on the first day after operation but survived after timely exploration. The other 18 flaps survived successfully after operation. Follow-up of 4 to 24 months after operation showed good texture and appearance in the flap repaired area; the color of the flap repaired area was similar to that of the normal skin around the recipient site, without pigmentation; the protective sensation was restored in all cases, but there was no two-point discrimination; there was no obvious hypertrophic scarring or pain in the donor or recipient site. At the last follow-up, the curative effect of flap repair was evaluated with 3 flaps being excellent and 16 flaps being good; the extension and flexion functions of the reserved digital joint were also assessed, being excellent in 8 fingers, good in 9 fingers, and fair in 2 fingers. Conclusions: The blood supply of superficial peroneal artery perforator flap is sufficient and reliable, and multiple flaps of this type or multiple flaps with one pedicle can be resected from one donor site. The use of this flap to repair small and medium-sized thermal crush injury wounds in the hand results in minimal damage to the donor area, and good postoperative appearance and texture of the flap.

Objective: To explore the effects of tensile force on vascular lumen formation in three-dimensional printed tissue. Methods: The experimental research method was used. Human umbilical vein endothelial cells (HUVECs) were extracted from discarded umbilical cord tissue of 3 healthy women (aged 22 to 35 years) who gave birth in the Department of Gynaecology and Obstetrics of Suzhou Ruihua Orthopaedic Hospital from September 2020 to May 2021. Human skin fibroblasts (HSFs) were extracted from discarded normal skin tissue of 10 male patients (aged 20 to 45 years) who underwent wound repair in the Department of Hand Surgery of Suzhou Ruihua Orthopaedic Hospital from September 2020 to September 2022. After identification of the two kinds of cells, the 4 th to 6 th passage of cells were taken for the follow-up experiments. HUVECs and HSFs were used as seed cells, and polycaprolactone, gelatin, hyaluronic acid, and fibrin were used as scaffold materials, and the three-dimensional printed vascularized tissue was created by three-dimensional bioprinting technology. The printed tissue with polycaprolactone scaffold of 6 and 10 mm spacing, and without polycaprolactone scaffold were set as 6 mm spacing polycaprolactone group, 10 mm spacing polycaprolactone group, and non-polycaprolactone group, respectively. After 4 days of culture, the printed tissue in 10 mm spacing polycaprolactone group was selected to detect the cell survival by cell viability detection kit, and the cell survival rate was calculated. After 14 days of culture, the printed tissue in three groups were taken, and the shape change of tissue was observed by naked eyes; immunofluorescence staining was performed to observe the arrangement of filamentous actin, and lumen diameter, total length, and number of branches of vessel in the tissue. The tissue with micro-spring structure in the above-mentioned three groups was designed, printed, and cultured for 9 days, and the tensile force applied in the printed tissue was measured according to the force-displacement curve. The number of samples was all 3 in the above experiments. Data were statistically analyzed with one-way analysis of variance and Tukey test. Results: After 4 days of culture, the cell survival rate in printed tissue in 10 mm spacing polycaprolactone group was (91.3±2.2)%. After 14 days of culture, the shape change of printed tissue in non-polycaprolactone group was not obvious, while the shape changes of printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were obvious. After 14 days of culture, the arrangement of filamentous actin in the printed tissue in non-polycaprolactone group had no specific direction, while the arrangement of filamentous actin in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group had a specific direction. After 14 days of culture, The vascular lumen diameters of the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were (6.0±1.3) and (10.8±1.3) μm, respectively, which were significantly larger than 0 μm in non-polycaprolactone group ( P <0.05), and the vascular lumen diameter of printed tissue in 10 mm spacing polycaprolactone group was significantly larger than that in 6 mm spacing polycaprolactone group ( P <0.05); the total length and number of branches of blood vessel in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were significantly shorter or less than those in non-polycaprolactone group ( P <0.05), and the total length and number of branches of blood vessel in the printed tissue in 10 mm spacing polycaprolactone group were significantly shorter or less than those in 6 mm spacing polycaprolactone group. After 9 days of culture, the tensile forces applied in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were (2 340±59) and (4 284±538) μN, respectively, which were significantly higher than 0 μN in non-polycaprolactone group ( P <0.05), and the tensile force applied in the printed tissue in 10 mm spacing polycaprolactone group was significantly higher than that in 6 mm spacing polycaprolactone group ( P <0.05). Conclusions: The three-dimensional printed scaffold structure can exert different tensile force in the printed tissue, and the vascular lumen diameter of the printed tissue can be regulated by adjusting the tensile force.

Objective: To explore the clinical effects of free anterolateral thigh perforator flap pedicled with descending genicular artery in repairing wounds after lower leg limb-sparing surgery. Methods: A retrospective observational study was conducted. From January 2019 to June 2021, 12 patients with wounds after lower leg limb-sparing surgery who met the inclusion criteria were admitted to Suzhou Ruihua Orthopedic Hospital, including 6 males and 6 females, aged 17 to 74 years, with original wound area ranging from 17 cm×9 cm to 40 cm×15 cm. Five patients had infection in wounds. The wounds were all repaired by free anterolateral thigh perforator flap from contralateral thigh, with area of 18 cm×10 cm to 37 cm×9 cm. The artery of flap was anastomosed with the descending genicular artery, and the wounds in donor areas were sutured directly. Seven patients were transplanted with split-thickness skin grafts from the contralateral thigh to cover the remaining wounds that can not be covered by flap and the wounds in donor areas were covered with gauze. During the operation, the types of perforating branch carried by flap and the types of arteries and veins in recipient areas were recorded. The survival and occurrence of vascular crisis of flap, the survival of skin graft, the wound healing in donor and recipient areas, and the length of hospital stay after flap transplant surgery were recorded. During follow-up, the color and texture of flap, reinfection in lower leg, and fracture healing were recorded. At the last follow-up, the limb salvage function of patients was evaluated according to the functional evaluation criteria of Chen Zhongwei's amputated limb replantation. Results: The types of perforating branches carried by flaps were as follows: 6 cases of only carrying the descending branch of the lateral circumflex femoral artery, 3 cases of only carrying the oblique branch of the lateral circumflex femoral artery, and 3 cases of carrying the descending branch of the lateral circumflex femoral artery and oblique branch of the lateral circumflex femoral artery after internal pressurization anastomosis. The types of arteries in the recipient area of flap were as follows: one case of main trunk of the descending genicular artery, 8 cases of the saphenous branch of the descending genicular artery, and 3 cases of the articular branch of the descending genicular artery. The types of veins in the recipient area of flap were as follows: 8 cases of one accompanying vein of the descending genicular artery and one branch of the great saphenous vein, and 4 cases of two branches of the great saphenous vein. All the flaps survived without vascular crisis, and all the skin grafts also survived. The wounds in the donor and recipient areas were all healed. The length of hospital stay of patient after flap transplant surgery ranged from 13 to 79 days. During the follow-up of 6 to 23 months, the color and texture of flap were both good, with no infection in lower leg wound. Internal or external fixation were removed after fracture healing in 5 patients, and bone graft internal fixation was performed in 7 patients whose fractures were not healed after surgery and all the incisions healed without infection. At the last follow-up, the limb salvage effect of patients was evaluated as followings: excellent in 7 patients, good in 4 patients, and fair in one patient. Conclusions: Free anterolateral thigh flap pedicled with descending genicular artery can effectively repair the wounds after lower leg limb-sparing surgery and control infection with short length of hospital stay, while not increasing the risk of secondary injury of distal limb vessels. Thus, it can obtain satisfactory limb salvage effect which is worthy of clinical promotion.

Blood transfusions are now an essential part of modern medicine. Transfusable red blood cells (RBCs) are employed in various therapeutic strategies; however, the processes of blood donation, collection, and administration still involve many limitations. Notably, a lack of donors, the risk of transfusion-transmitted disease, and recent pandemics such as COVID-19 have prompted us to search for alternative therapeutics to replace this resource. Originally, RBC production was attempted via the ex vivo differentiation of stem cells. However, a more approachable and effective cell source is now required for broader applications. As a viable alternative, pluripotent stem cells have been actively used in recent research. In this review, we discuss the basic concepts related to erythropoiesis, as well as early research using hematopoietic stem cells ex vivo, and discuss the current trend of in vitro erythropoiesis using human-induced pluripotent stem cells., (© 2023. The Author(s) under exclusive licence to Japan Human Cell Society.)

Objective: To summarize the morphological characteristics of the transverse branch of lateral femoral circumflex artery (LFCA) using digital subtraction angiography (DSA) and explore its clinical significance. Methods: A retrospective observational study was conducted. From October 2020 to May 2021, 62 patients with soft tissue injuries in the extremities were hospitalized in Suzhou Ruihua Orthopedic Hospital, including 40 males and 22 females, aged from 20 to 72 years. DSA was performed in the lateral femoral region of patients before the anterolateral thigh flap transplantation, and in combination with imaging scale to observe and measure the general condition of the blood vessels and the occurrence (with the occurrence rate being calculated), source artery, location of the origin point, direction of course, and the location of the perforating point of the cutaneous perforator of the transverse branch of LFCA, and in addition to classify the morphological characteristics of the transverse branch. Results: DSA detection showed that the femoral artery, the deep femoral artery, and the branches of LFCA were clearly distinguishable in 62 patients. Transverse branches of LFCA were observed in 59 patients, including 52 cases with a single transverse branch, and 7 cases with double transverse branches. The occurrence rate of transverse branches was 95.2% (59/62). A total of 66 transverse branches of LFCA were observed, of which 3 originated from the deep femoral artery, and 63 originated from the LFCA. The origin point of the transverse branch was 6.5-12.7 cm away from the anterior superior iliac spine. The transverse branch which was approximately perpendicular to the long axis of the body, originated outwards, ran between the ascending branch of LFCA and the oblique branch of LFCA, and branched along the way, with the trunk running under the greater trochanter. The perforating point of the cutaneous perforator of the transverse branch was 8.0-18.0 cm away from the anterior superior iliac spine. In the classification of morphological characteristics of the transverse branch of LFCA, the most common type was the one that originated from the same trunk with other branches of LFCA, accounting for 50.0% (31/62), followed by the one that originated from the singular trunk of LFCA (12 cases) or deep femoral artery (3 cases), accounting for 24.2% (15/62); the special type accounted for 21.0% (13/62), including 7 cases of double transverse branches and 6 cases of the transverse branch originated from the same trunk with multiple other branches of LFCA; those with small/absent transverse branch only accounted for 4.8% (3/62). Among the above-mentioned common trunk relationship of two branches, those with shared trunk of ascending and transverse branches were most frequently observed, accounting for 77.4% (24/31); those with shared trunks of the transverse and oblique branches (5 cases) and the transverse and descending branches (2 cases) accounted for 22.6% (7/31) altogether. Conclusions: A high incidence rate of the transverse branch of LFCA is observed through DSA. The transverse branch originates from the lateral femoral artery approximately perpendicular to the long axis of the body, mainly from the same trunk with another main branch of LFCA, especially the ascending branch. This positioning analysis can provide an important reference for the design and resection of anterolateral femoral flaps.

Objective: To investigate the curative effects of the superficial peroneal artery perforator flap carrying two and more homologous perforators in repairing hand and foot wounds. Methods: A retrospective observational study was conducted. From January to September 2021, 23 patients with hand and foot wounds combined with bone or tendon exposure who met the inclusion criteria were admitted to Suzhou Ruihua Orthopaedic Hospital, including 16 males and 7 females, aged 23 to 68 years. After expansion of the wound, the wound area was 3.0 cm×2.0 cm to 11.0 cm×4.0 cm. All the wounds were repaired with the superficial peroneal artery perforator flap carrying two and more homologous perforators. The area of the resected flap was 4.0 cm×2.0 cm to 12.0 cm×5.0 cm. All the wounds in donor areas were sutured directly. During the operation, the resection of the flap, the number and caliber of carried perforators, the caliber of superficial peroneal artery, the length of vascular pedicle, and the number of accompanying veins of the superficial peroneal artery were recorded. The survival of the flap, the occurrence of complications, and the wound healing in the donor area were observed after operation. The recovery of the donor and recipient areas was followed up. At the last follow-up, the comprehensive evaluation scale was used to evaluate the curative effect of flap repair, and the sensory grading scale was used to evaluate the sensory function of the recipient area. Results: Totally 24 flaps were successfully resected in surgical operations, carrying 56 superficial peroneal artery perforators in total, with the caliber of perforators of 0.20-0.70 mm. The calibers of all perforators carried by 7 flaps were smaller than 0.40 mm. Nineteen flaps carried 2 perforators each, 3 flaps carried 3 perforators each, 1 flap carried 4 perforators, and 1 flap carried 5 perforators. During the operation, the superficial peroneal artery was resected with a caliber of 0.40-1.50 mm, the vascular pedicle was 2-6 cm in length, and each superficial peroneal artery had two accompanying veins. After operation, all the flaps survived smoothly, no vascular crisis or distal necrosis occurred, and the wounds healed well in the donor area. During the follow-up of 6 to 10 months after operation, the color, texture, and elasticity of the recipient area were good. Among them, 6 recipient areas were thinned and reshaped because of bloating. There was only linear scar and no obvious scar hyperplasia or pigmentation in the donor area, without significant change in sensory or motor function. At the last follow-up, the curative effect evaluation of flap repair was excellent in 22 flaps and good in 2 flaps, and the sensory function evaluation of the recipient area was grade S 3 in 1 area and grade S 2 in 23 areas. Conclusions: The superficial peroneal artery perforator flap with two and more homologous perforators has sufficient and reliable blood supply and is effective in repairing hand and foot wounds. It provides an ideal solution for the clinical problem in which the original operation scheme is abandoned due to the existence of only multiple slender perforators of caliber smaller than 0.40 mm, and only a single perforator in the operative field that cannot satisfy the needs of the flap blood supply and recipient area.

Background: To support the sustainability of biodiesel production, by-products, such as crude glycerol, should be converted into high-value chemical products. 1,2-propanediol (1,2-PDO) has been widely used as a building block in the chemical and pharmaceutical industries. Recently, the microbial bioconversion of lactic acid into 1,2-PDO is attracting attention to overcome limitations of previous biosynthetic pathways for production of 1,2-PDO. In this study, we examined the effect of genetic engineering, metabolic engineering, and control of bioprocess factors on the production of 1,2-PDO from lactic acid by K. pneumoniae GEM167 with flux enhancement of the oxidative pathway, using glycerol as carbon source., Results: We developed K. pneumoniae GEM167ΔadhE/pBR-1,2PDO, a novel bacterial strain that has blockage of ethanol biosynthesis and biosynthesized 1,2-PDO from lactic acid when glycerol is carbon source. Increasing the agitation speed from 200 to 400 rpm not only increased 1,2-PDO production by 2.24-fold to 731.0 ± 24.7 mg/L at 48 h but also increased the amount of a by-product, 2,3-butanediol. We attempted to inhibit 2,3-butanediol biosynthesis using the approaches of pH control and metabolic engineering. Control of pH at 7.0 successfully increased 1,2-PDO production (1016.5 ± 37.3 mg/L at 48 h), but the metabolic engineering approach was not successful. The plasmid in this strain maintained 100% stability for 72 h., Conclusions: This study is the first to report the biosynthesis of 1,2-PDO from lactic acid in K. pneumoniae when glycerol was carbon source. The 1,2-PDO production was enhanced by blocking the synthesis of 2,3-butanediol through pH control. Our results indicate that K. pneumoniae GEM167 has potential for the production of additional valuable chemical products from metabolites produced through oxidative pathways., (© 2023. The Author(s).)

Objective: To explore the anatomical characteristics of the anterolateral thigh perforator flap pedicled with oblique branch trunk of lateral circumflex femoral artery in the muscular septum and the clinical effect of this flap in repairing skin and soft tissue defects in the extremities. Methods: A retrospective observational study was conducted. From December 2020 to April 2021, 59 patients with skin and soft tissue defects in the extremities admitted to the Department of Hand Surgery of Suzhou Ruihua Orthopaedic Hospital met the inclusion criteria, including 46 males and 13 females, aged 20 to 81 years. The wound area after debridement ranged from 8 cm×5 cm to 38 cm×20 cm. According to the condition of the wound, the perforators in the anterolateral femoral region on the unaffected side were located by color Doppler ultrasound. The anterolateral thigh perforator flap with the oblique branch of lateral circumflex femoral artery as the source artery was designed, and the wound was repaired by unilateral flap or series combination of bilateral flaps (with the area of unilateral flap ranging from 7 cm×5 cm to 37 cm×11 cm). The wound of the donor site was sutured directly. The following items were recorded, including the number of perforators in the anterolateral femoral region marked before operation, the course characteristics of oblique branch trunk of lateral circumflex femoral artery and its perforators, and the number, origin, and type of perforators observed during operation, the flap repair mode and the flap harvest time. After operation, the survival condition of the flap, the wound healing time in the recipient site, and the suture healing in the donor area were observed, and the recovery of the donor and recipient areas was followed up. At the last follow-up, the sensation function evaluated by sensory rating scale of British Medical Research Association and two-point discrimination of the area transplanted with flap were recorded, and the improved comprehensive curative effect evaluation scale of flap was used to evaluate the repair effect of the flap. Results: A total of 156 perforators were marked in the anterolateral femoral region before operation, and 144 perforators were observed during the operation, of which 98 came from the oblique branch of the lateral circumflex femoral artery, and the first perforator of the oblique branch was the intermuscular septal perforator. Once formed, most oblique branch trunk of lateral circumflex femoral artery in the muscular septum could be divided into the deep branch and the superficial branch at the middle and upper 1/3 junction of the line between the anterior superior iliac spine and the lateral edge of the patella, the deep branch mainly ran in the muscle of vastus intermedius and vastus lateralis, and rarely developed the skin perforators, while the superficial branch mainly ran in the muscular septum between the rectus femoris and the vastus lateralis, and grew out the perforators to the proximal skin of the anterolateral femoral region. Fifty-six patients were repaired with unilateral flap and 3 patients with bilateral flap in series combination, with the harvesting time of the unilateral flap ranged from 9 to 99 min. Three patients developed arterial crisis within 48 hours after operation and survived after timely exploration; the flap of 1 patient developed necrosis 11 days after operation and was repaired by abdominal split-thickness skin graft; the other flaps survived smoothly. The wound healing time in the recipient area was 10 to 42 days after operation, and the sutures in the donor area healed well. During the follow-up of 6 to 10 months, 8 patients underwent thinning and plastic surgery 6 months after operation because of bloating in the flap transplantation area, while the other patients had a good shape of the flap transplantation area, with no deep tissue infection such as osteomyelitis, with soft texture, good elasticity, no pain, and good blood circulation; all the donor areas were left with linear scars, normal blood circulation in the distal extremities, no limitation of knee joint motion or quadriceps muscle strength. At the last follow-up, the sensation function was restored in the flap transplantation area of the affected limb, including 14 cases of S 1 grade and 45 cases of S 2 grade; there was only one point of two-point discrimination; the curative effect evaluation of flap repair included excellent in 24 cases, good in 35 cases, and general in 3 cases. Conclusions: The anterolateral thigh perforator flap pedicled with oblique branch trunk of lateral circumflex femoral artery in the muscular septum has the advantages of relatively concealed donor area, large cutting width, and simple operation during surgery. It protects the donor area to the greatest extent while repairing skin and soft tissue defects in the extremities, and is a useful supplement to the classic anterolateral thigh perforator flap.

Objective: To investigate the regularity of sensory recovery after repairing the wounds on the wrist and back of hand with anterolateral femoral flap without nerve anastomosis. Methods: A cross-sectional study was conducted. From January 2018 to December 2020, patients who underwent free anterolateral femoral flaps without nerve anastomosis to repair wounds on the wrist and back of hand and met the inclusion criteria in Changshu Hai Yu Health Centre and Suzhou Ruihua Orthopedic Hospital were included in this study. Depending on the time interval between the day of the patient's surgery and the day of the cross-sectional survey, 80 patients were divided into 6-month group (15 males and 5 females, aged 22-63 years), 12-month group (16 males and 4 females, aged 21-65 years), 18-month group (15 males and 5 females, aged 25-61 years), and 24-month group (14 males and 6 females, aged 20-65 years), with 20 patients in each group. The area of skin and soft tissue defects after debridement ranged from 6.0 cm×4.5 cm to 18.0 cm×9.0 cm. Anterolateral femoral flaps were cut with areas of 7 cm×5 cm to 20 cm×10 cm and a thickness of 1.0 to 2.5 cm. Each transplanted flap was divided into A (proximal), B/D (bilateral), C (distal), and E (central) regions. The pain sensation, touch sensation, cold sensation, warmth sensation, and two-point discrimination (2-PD) in the aforementioned five regions and the differences in the five senses of the whole flap were tested and compared. Data were statistically analyzed with one-way analysis of variance, Fisher's exact probability test, chi-square test, or McNemar test. Results: In A region of anterolateral femoral flap without nerve anastomosis, compared with those in 6-month group, the pain sensation, touch sensation, cold sensation, and warmth sensation of flap of patients in 12-month group were significantly recovered (with χ 2 values of 10.10, 14.55, 12.13, and 4.29, respectively, P <0.05 or P <0.01); compared with that in 12-month group, the warmth sensation of flap of patients in 18-month group recovered significantly ( χ 2 =5.23, P <0.05). In B region, compared with those in 6-month group, the pain sensation, touch sensation, and cold sensation of flap of patients in 12-month group recovered significantly (with χ 2 values of 5.58, 3.96, and 4.29, respectively, P <0.05); compared with those in 12-month group, the pain sensation, touch sensation, cold sensation, and warmth sensation of flap of patients in 18-month group recovered significantly (with χ 2 values of 5.58, 3.96, 7.03, and 12.38, respectively, P <0.05 or P <0.01). In C region, compared with that in 6-month group, the pain sensation of flap of patients in 12-month group recovered significantly ( χ 2 =4.80, P <0.05); Compared with that in 12-month group, the warmth sensation of flap of patients in 18-month group recovered significantly ( χ 2 =10.16, P <0.01). In D region, compared with those in 6-month group, the pain sensation, touch sensation, and cold sensation of flap of patients in 12-month group recovered significantly (with χ 2 values of 5.58, 4.29, and 3.96, respectively, P <0.05); compared with those in 12-month group, the pain sensation, touch sensation, cold sensation, and warmth sensation of flap of patients in 18-month group recovered significantly (with χ 2 values of 5.58, 4.29, 3.96, and 10.10, respectively, P <0.05 or P <0.01). In E region, compared with that in 6-month group, the cold sensation of flap of patients in 12-month group recovered significantly ( χ 2 =4.80, P <0.05); compared with those in 12-month group, the pain sensation, touch sensation, and warmth sensation of flap of patients in 18-month group recovered significantly (with χ 2 values of 6.47, 4.91, and 9.23, respectively, P <0.05 or P <0.01). The five senses in the 5 regions of flap of patients in 24-month group were similar to those in 18-month group ( P >0.05). The recovery of 2-PD in the 5 regions of flap of patients was similar between the two adjacent groups ( P >0.05). In 12-month group, the recoveries of pain sensation, touch sensation, and cold sensation of flap of patients in A region were better than those in the other 4 regions ( P <0.05 or P <0.01), the recovery of warmth sensation was better than that of B region, C region, and E region ( P <0.05 or P <0.01); in 18-month group, the recovery of pain sensation, touch sensation, cold sensation, and warmth sensation of flap of patients in A region of was better than those in area C region ( P <0.05). Compared with those in 6-month group, the pain sensation, touch sensation, and cold sensation of the whole flap of patients in 12-month group recovered significantly (with χ 2 values of 7.62, 7.03, and 5.58, respectively, P <0.05 or P <0.01). Compared with the 12-month group in which 10, 11, 10, and 4 patients had a recovery of pain, touch sensation, cold sensation, and warmth sensation in the whole flap, the 18-month group had significantly more patients with sensations recovered, which were 17, 17, 16, and 14, respectively (with χ 2 values of 5.58, 4.29, 3.96, and 10.10, respectively, P <0.05 or P <0.01). The five senses of the whole flap of patients in 24-month group were similar to those in 18-month group ( P >0.05). Conclusions: In the anterolateral femoral flap without nerve anastomosis for repairing wounds on the wrist and back of hand, the sensation gradually recovered from the proximal end to the distal end. The sensation of touch, pain, and cold began to recover from 6 months after operation, and entered the stable recover period at 18 months after operation. Warmth sensation began to recover from 12 months after operation, and entered the stable recovery period at 18 months after operation. The 2-PD of most flaps was still not recovered 2-year after operation.

Association between exposure to periodontal bacteria and development of autoantibodies related to rheumatoid arthritis (RA) has been widely accepted; however, direct causal relationship between periodontal bacteria and rheumatoid factor (RF) is currently not fully understood. We investigated whether periodontal bacteria could affect RF status. Patients with preclinical, new-onset, or chronic RA underwent periodontal examination, and investigation of subgingival microbiome via 16S rRNA sequencing. Degree of arthritis and RF induction was examined in collagen-induced arthritis (CIA) mice that were orally inoculated with different periodontal bacteria species. Subsequently, single-cell RNA sequencing analysis of the mouse spleen cells was performed. Patients with preclinical RA showed an increased abundance of the Porphyromonadacae family in the subgingival microbiome compared to those with new-onset or chronic RA, despite comparable periodontitis severity among them. Notably, a distinct subgingival microbial community was found between patients with high-positive RF and those with negative or low-positive RF (p=0.022). Oral infections with the periodontal pathogens P. gingivalis and Treponema denticola in CIA mice similarly enhanced arthritis score, but resulted in different levels of RF induction. Genes related to B cell receptor signaling, B cell proliferation, activation, and differentiation, and CD4 + T cell costimulation and cytokine production were involved in the differential induction of RF in mice exposed to different bacteria. In summary, periodontal microbiome might shape RF status by affecting the humoral immune response during RA pathogenesis., (© 2022. The Author(s).)

Objective: To compare the effects between second toe tibial dorsal artery flap (2-TDAF) and second toe tibial plantar proper artery flap (2-TPPAF) in repairing finger skin and soft tissue defects. Methods: A retrospective cohort study was conducted. From January 2019 to June 2020, 27 patients with skin and soft tissue defects at the fingertips with area of 1.5 cm×1.2 cm-2.6 cm×1.8 cm after debridement who met the inclusion criteria were admitted to Suzhou Ruihua Orthopaedic Hospital, including 21 males and 6 females, aged 19-59 (37±10) years. According to flap repair methods used in the defective fingers, the patients were divided into 2-TDAF group (12 cases) and 2-TPPAF group (15 cases). The area of 2-TDAF ranged from 1.5 cm×1.2 cm to 2.5 cm×1.6 cm, and the area of 2-TPPAF ranged from 1.7 cm×1.3 cm to 2.6 cm×1.8 cm. Full-thickness skin grafts from the medial side of the ipsilateral leg were grafted to the wounds in donor sites, and the wounds in donor sites of skin grafts were directly sutured. Flap arterial diameter, flap excision time, flap survival situation of patients in 2 weeks after operation, and follow-up time were recorded. At the last follow-up, the two-point discrimination distance of flap graft site, total action motion (TAM) of the finger joints, and wound healing of the flap donor site were recorded; the Vancouver scar scale (VSS) was used to score the scar in donor area of the second toe and the recipient area of fingers; the appearance and self-satisfaction subscales of the Michigan hand outcomes questionnaire (MHQ) were used to evaluate the affected finger. Data were statistically analyzed with independent sample t test or Fisher's exact probability test. Results: The flap artery diameter of patients in 2-TDAF group was 0.35-0.80 (0.56±0.14) mm and the flap cutting time was (14.0±2.7) min, which were significantly shorter than 0.80-1.35 (1.02±0.16) mm and (19.7±3.4) min in 2-TPPAF group (with t values of 7.81 and 4.79, respectively, P <0.01). The flaps of patients in the 2 groups in recipient areas survived well in 2 weeks after operation, and the wounds in donor areas of flaps of patients in the 2 groups healed well at the last follow-up. There was no statistically significant difference in the postoperative follow-up time, and two-point discrimination distance of flap graft site, TAM of the finger joints, VSS score of scar in the second toe donor site and the finger recipient site, and the appearance and self-satisfaction of MHQ scores of the affected finger at the last follow-up ( P >0.05). Conclusions: Compared with 2-TPPAF, 2-TDAF has a shallower anatomical layer and shorter time for surgical flap removal, which can preserve the proper arteries and nerves at the base of the toes and reduce the damage to the donor site.

Objective: To explore the clinical effects of proximal ulnar artery perforator flap combined with iliac bone graft in the reconstruction of subtotal thumb or finger defects. Methods: A retrospective observational study was conducted. From August 2016 to August 2019, 7 patients with thumb or finger defects caused by mechanical damage who met the inclusion criteria were admitted to Ruihua Affiliated Hospital of Soochow University, including 6 males and 1 female, aged 46 to 58 years. Their length of fingers was repaired with iliac bone, with length of 2.0 to 3.0 cm. After the bone graft, the skin defect area of the affected finger ranged from 2.8 cm×2.2 cm to 6.0 cm×3.2 cm. Then the free proximal ulnar artery perforator flap with area of 3.0 cm×2.4 cm to 6.5 cm×3.5 cm was used to cover the wounds. The wounds in donor sites of iliac crest and flap were directly sutured. The survival of flap in one week post surgery and the donor site wound healing in 2 weeks post surgery were observed, respectively. During the follow-up, the appearance and sensory function of the affected finger, bone healing, and scar hypertrophy of wound in the donor site were observed and evaluated. At the last follow-up, the functional recovery of the affected finger was evaluated with trial standard for the evaluation of functions of the upper limbs of the Hand Surgery Society of Chinese Medical Association. Results: In one week post surgery, all the flaps survived. In 2 weeks post surgery, the iliac bone and the wounds in forearm donor site healed. During the follow-up of 5 to 13 months, the flap was good in appearance, without obvious pigmentation; the sensory recovery reached level S 2 in 5 patients and S 0 in 2 patients; all the grafted iliac bones were bony union without obvious resorption; the wounds in donor site healed well, with only mild scar formation. At the last follow-up, the shape of the reconstructed finger was close to the healthy finger, and the functional evaluation results were excellent in 3 cases and good in 4 cases. Conclusions: The use of proximal ulnar artery perforator flap combined with iliac bone graft to reconstruct subtotal thumb or finger can partially restore part of the appearance and function, with less damage to the donor site. It is a good choice for patients who have low expectations of appearance and function for the reconstructed finger.

Transforming growth factor-beta (TGF-β) is an important regulator of joint homeostasis, of which dysregulation is closely associated with the development of osteoarthritis (OA). In normal conditions, its biological functions in a joint environment are joint protective, but it can be dramatically altered in different contexts, making its therapeutic application a challenge. However, with the deeper insights into the TGF-β functions, it has been proven that TGF-β augments cartilage regeneration by chondrocytes, and differentiates both the precursor cells of chondrocytes and stem cells into cartilage-generating chondrocytes. Following documentation of the therapeutic efficacy of chondrocytes augmented by TGF-β in the last decade, there is an ongoing phase III clinical trial examining the therapeutic efficacy of a mixture of allogeneic chondrocytes and TGF-β-overexpressing cells. To prepare cartilage-restoring chondrocytes from induced pluripotent stem cells (iPSCs), the stem cells are differentiated mainly using TGF-β with some other growth factors. Of note, clinical trials evaluating the therapeutic efficacy of iPSCs for OA are scheduled this year. Mesenchymal stromal stem cells (MSCs) have inherent limitations in that they differentiate into the osteochondral pathway, resulting in the production of poor-quality cartilage. Despite the established essential role of TGF-β in chondrogenic differentiation of MSCs, whether the coordinated use of TGF-β in MSC-based therapy for degenerated cartilage is effective is unknown. We herein reviewed the general characteristics and mechanism of action of TGF-β in a joint environment. Furthermore, we discussed the core interaction of TGF-β with principal cells of OA cell-based therapies, the chondrocytes, MSCs, and iPSCs. Impact Statement Transforming growth factor-beta (TGF-β) has been widely used as a core regulator to improve or formulate therapeutic regenerative cells for degenerative joints. It differentiates stem cells into chondrocytes and improves the chondrogenic potential of differentiated chondrocytes. Herein, we discussed the overall characteristics of TGF-β and reviewed the comprehension and utilization of TGF-β in cell-based therapy for degenerative joint disease.

Objective: To investigate the clinical features and associated underlying conditions of isolated tuberculous myositis (ITBM), a rare extrapulmonary tuberculosis (TB)., Methods: A systematic literature search and a multicenter survey were performed using a triangulation strategy. Data from the identified ITBM cases were extracted and analyzed to determine the underlying conditions, clinical presentations, treatments, and outcomes., Results: Based on the systematic review, we identified 58 ITBM, including 9 pediatric, cases in the literature published from 1981 to 2021 25 (43.1%) immunocompromised and 33 (56.9%) non-immunocompromised patients. Immunocompromised cases had a significant shorter symptom duration (median 30.0 vs. 75.0 days) and a higher prevalence of multilocular involvement (20.8% vs. 0%). Among 24 immunocompromised adult patients, dermatomyositis/polymyositis (DM/PM; n=10, 41.7%) were the most common underlying diseases in adults with ITBM identified in the systematic review. Over the past 20 years, 11 Korean adults with ITBM were identified in the multicenter survey. Of 7 immunocompromised cases, two (28.6%) were DM/PM patients. TB death rate of immunocompromised patients was 0.0% and 5/23 (21.7%) in the pediatric and adult ITBM cases identified in the systematic review, respectively, and 3/7 (42.9%) in survey-identified ITBM cases., Conclusion: ITBM has a unique clinical presentation including fever, tenderness, local swelling, overlying erythema, abscess formation and was associated with a grave outcome, especially in immunocompromised hosts. DM/PM was a highly prevalent underlying disease in both systematic review-identified and survey-identified immunocompromised ITBM patients., Competing Interests: CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported., (Copyright © 2022 by The Korean College of Rheumatology. All rights reserved.)

Background and Objectives: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease mainly affecting young women of childbearing age. SLE affects the skin, joints, muscles, kidneys, lungs, and heart. Cardiovascular complications are common causes of death in patients with SLE. However, the complexity of the cardiovascular system and the rarity of SLE make it difficult to investigate these morbidities. Patient-derived induced pluripotent stem cells (iPSCs) serve as a novel tool for drug screening and pathophysiological studies in the absence of patient samples., Methods and Results: We differentiated CMs from HC- and SLE-iPSCs using 2D culture platforms. SLE-CMs showed decreased proliferation and increased levels of fibrosis and hypertrophy marker expression; however, HC-and SLE-monolayer CMs reacted differently to SLE serum treatment. HC-iPSCs were also differentiated into CMs using 3D spheroid culture and anti-Ro autoantibody was treated along with SLE serum. 3D-HC-CMs generated more mature CMs compared to the CMs generated using 2D culture. The treatment of anti-Ro autoantibody rapidly increased the gene expression of fibrosis, hypertrophy, and apoptosis markers, and altered the calcium signaling in the CMs., Conclusions: iPSC derived cardiomyocytes with patient-derived serum, and anti-Ro antibody treatment could serve in effective autoimmune disease modeling including SLE. We believe that the present study might briefly provide possibilities on the application of a combination of patient-derived materials and iPSCs in disease modeling of autoimmune diseases.

Objective: To explore the clinical effects of free superficial peroneal artery perforator flaps in repairing skin and soft tissue defects of the hallux. Methods: A retrospective observational study was conducted. From January 2020 to January 2021, 13 patients with skin and soft tissue defects of the hallux who met the inclusion criteria were admitted to Department of Foot and Ankle Surgery of Ruihua Affiliated Hospital of Soochow University, including 12 males and 1 female, aged 26 to 53 years. Before operation, the perforating point of the superficial peroneal artery perforator was located by color Doppler ultrasound on the calf on the same side of the affected hallux and marked on the body surface. The operation was performed under spinal anesthesia combined with continuous epidural anesthesia. The area of skin and soft tissue defect after debridement was 4.5 cm×2.5 cm to 12.0 cm×3.0 cm. According to the size and shape of the wound, the superficial peroneal artery perforator flap was designed with the line between the fibular head and the lateral malleolus tip parallel shifting 2 cm to the tibial side as the flap axis line, and the perforating point of the perforator near the midpoint of the axis line as the center. The cut area of the flap was 5.0 cm×3.0 cm to 13.0 cm×4.0 cm, and part of the deep fascia was cut when the pedicle was freed. The donor site wound was sutured directly. During the operation, the number and type of the perforator and the cutting time of the flap were recorded, and the length of the perforator pedicle and diameter of the perforator were measured. The survival of the flap, the healing time and the healing condition of the donor and recipient areas were recorded after operation. The color, texture, elasticity of the flap, standing and walking functions of patients, the recovery of the donor area, and the patients' satisfaction with the recovery of the donor and recipient areas were recorded during the follow-up. At the last follow-up, the sensation of the flap was evaluated by the British Medical Association sensory function evaluation standard, the function of the affected limb was evaluated by the American Society of Foot and Ankle Surgery scoring system, and the excellent and good rate of the function of the affected limb was calculated. Results: A total of 13 perforators of the superficial peroneal artery were detected during the operation, all of which were septocutaneous perforators, and the perforator diameter was 0.3 to 0.5 mm. The vascular pedicle length was 2 to 5 cm. Flap cutting time was 11 to 26 minutes. The flaps of 13 patients all survived completely. The wounds at the donor and recipient sites healed well 9 to 18 days after operation. During follow-up of 6 to 14 months, the flaps had good color, texture, and elasticity; 11 patients had no obvious bloated appearance, and the other 2 patients underwent flap thinning and plastic surgery in the second stage because of their bloated appearance; all the patients returned to normal walking and standing functions. There was only one linear scar left in the donor site, with no obvious scar hyperplasia or hyperpigmentation. All the patients were satisfied with the recovery of the donor and recipient areas. At the last follow-up, the sensation of the flap was evaluated as grade S 3 in 2 cases, grade S 2 in 9 cases, and grade S 1 in 2 cases; the function of the affected limb was evaluated as excellent in 7 cases and good in 6 cases, with an excellent and good rate of 100%. Conclusions: The free superficial peroneal artery perforator flap has relatively constant vascular anatomy, which is thin and wear-resistant, with less damage to the donor site after flap excision, and can preserve the shape and function of the hallux to the greatest extent. It is an effective method for repairing skin and soft tissue defect of the hallux.

Rabbits are being increasingly used as companion animals, and in research; thus, the need for proper veterinary care for rabbits has increased. Surgical access is more challenging in rabbits under inhalation anesthesia compared to other animals, such as dogs and cats. Rabbits have a very narrow and deep oral cavity, large incisors, and a large tongue. Moreover, their temporomandibular joint has limited mobility, making it more difficult to approach the larynx. Various methods have been proposed to overcome this difficulty. The video laryngoscope was introduced in 1999 and is useful when airway intubation is unsuccessful using a conventional laryngoscope. We postulated that a video laryngoscope with a modified size 1 Macintosh blade (McGrath MAC Video Laryngoscope, Medtronic, USA) would facilitate the intubation of New Zealand White rabbits. Sixteen specific-pathogen-free male New Zealand White rabbits weighing 3.45-4.70 kg were studied. All rabbits were intubated using the video laryngoscope. Typically, a 3.0 mm endotracheal tube was used for rabbits weighing < 4 kg, while a 3.5 mm tube was used in those weighing > 4 kg. During surgery, anesthesia was well maintained, and there were no major abnormalities in the animals' conditions. No rabbit developed breathing difficulties or anorexia after recovering from anesthesia. We established an intubation method using a video laryngoscope with a modified blade and stylet in the supine (ventrodorsal) position and successfully applied it in 16 rabbits. It is useful for training novices and for treating rabbits in veterinary hospitals with few staff members and animal research facilities where there are insufficient human resources., (© 2022. The Author(s).)

Background: The rarity of systemic sclerosis (SSc) has hampered the development of therapies for this intractable autoimmune disease. Induced pluripotent stem cell (iPSC) can be differentiated into the key disease-affected cells in vitro. The generation of patient-derived iPSCs has opened up possibilities for rare disease modeling. Since these cells can recapitulate the disease phenotypes of the cell in question, they are useful high-throughput platforms for screening for drugs that can reverse these abnormal phenotypes., Methods: SSc iPSC was generated from PBMC by Sendai virus. Human iPSC lines from SSc patients were differentiated into dermal fibroblasts and keratinocytes. The iPSC-derived differentiated cells from the SSc patients were used on high-throughput platforms to screen for FDA-approved drugs that could be effective treatments for SSc., Results: Skin organoids were generated from these cells exhibited fibrosis that resembled SSc skin. Screening of the 770-FDA-approved drug library showed that the anti-osteoporotic drug raloxifene reduced SSc iPSC-derived fibroblast proliferation and extracellular matrix production and skin fibrosis in organoids and bleomycin-induced SSc-model mice., Conclusions: This study reveals that a disease model of systemic sclerosis generated using iPSCs-derived skin organoid is a novel tool for in vitro and in vivo dermatologic research. Since raloxifene and bazedoxifene are well-tolerated anti-osteoporotic drugs, our findings suggest that selective estrogen receptor modulator (SERM)-class drugs could treat SSc fibrosis., (© 2022. The Author(s).)

Objective: To investigate whether initial whole spine magnetic resonance imaging (MRI) predicts radiographic progression and inflammatory activity in patients with axial spondyloarthritis (axSpA)., Methods: A retrospective analysis of spine MRI and X-rays from 70 axSpA patients was conducted. The number of affected discovertebral units was determined according to the definition of pathologic lesions on spine MRI set down by the ASAS/OMERACT group. Radiographic progression was defined as an increase in the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) of≥2 compared with baseline. The association of spine MRI with radiographic progression, cumulative C-reactive protein (CRP), and cumulative erythrocyte sedimentation rate (ESR) was investigated., Results: The axSpA-relevant lesions on spine MRI at baseline were independent predictors of radiographic progression. Arthritis of the costovertebral and costotransverse joints on MRI showed the highest odds ratio at 3years (OR [95% CI]: 2.54 [1.29-5.02]). Receiver operating characteristic curve analysis revealed that the area under the curve (AUC) for radiographic progression at 2years was 0.89 [95% CI: 0.81-0.96] for structural lesions and 0.83 [95% CI: 0.72-0.94] for inflammatory lesions. Notably, subgroup analysis of 26 patients with mSASSS=0 showed that fatty metaplasia on MRI were highly predictive of radiographic progression at 3years (AUC [95% CI]: 0.87 [0.61-1.00]). Moreover, 3-year cumulative ESR and CRP values increased in proportion to the extent of inflammatory lesions on initial MRI., Conclusion: Initial MRI assessment of the whole spine may predict radiographic progression and subsequent systemic inflammatory burden in axSpA patients, particularly those without axSpA-relevant abnormalities on spine X-rays., (Copyright © 2022 Société française de rhumatologie. Published by Elsevier Masson SAS. All rights reserved.)

To address the demands of emerging data-centric computing applications, ferroelectric field-effect transistors (Fe-FETs) are considered the forefront of semiconductor electronics owing to their energy and area efficiency and merged logic-memory functionalities. Herein, the fabrication and application of an Fe-FET, which is integrated with a van der Waals ferroelectrics heterostructure (CuInP 2 S 6 /α-In 2 Se 3 ), is reported. Leveraging enhanced polarization originating from the dipole coupling of CIPS and α-In 2 Se 3 , the fabricated Fe-FET exhibits a large memory window of 14.5 V at V GS = ±10 V, reaching a memory window to sweep range of ≈72%. Piezoelectric force microscopy measurements confirm the enhanced polarization-induced wider hysteresis loop of the double-stacked ferroelectrics compared to single ferroelectric layers. The Landau-Khalatnikov theory is extended to analyze the ferroelectric characteristics of a ferroelectric heterostructure, providing detailed explanations of the hysteresis behaviors and enhanced memory window formation. The fabricated Fe-FET shows nonvolatile memory characteristics, with a high on/off current ratio of over 10 6 , long retention time (>10 4 s), and stable cyclic endurance (>10 4 cycles). Furthermore, the applicability of the ferroelectrics heterostructure is investigated for artificial synapses and for hardware neural networks through training and inference simulation. These results provide a promising pathway for exploring low-dimensional ferroelectronics., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Introduction: Chronic kidney disease (CKD) is a major risk factor for overall morbidity and mortality even in lupus nephritis (LN) patients. However, less attention has been paid to the development of CKD in patients with LN. The objective of this study was to identify predictors for CKD with 35-year experience depending on newly revised guidelines for patients with LN., Methods: We conducted a retrospective cohort study for 401 patients who visited Seoul St. Mary's Hospital between January 1985 and December 2019. We analyzed clinical and laboratory indices, treatment response, the final renal function, and biopsy findings. The timing and cumulative risk of developing CKD were identified by Kaplan-Meier methods. Independent risk factors for developing CKD were examined by Cox proportional hazard regression analyses., Results: The median follow-up time after the diagnosis of LN was 131 months. CKD occurred in 15.5% of patients within 10 years after the diagnosis of LN. The development of CKD was associated with delayed-onset LN, acute renal dysfunction at onset of LN, and failure to reach complete response (CR) at 6 or 12 months rather than histopathological findings or the severity of proteinuria at onset of LN. Cumulative incidence of progression to CKD was significantly higher in patients with the three predictors mentioned above., Conclusion: Ten-year cumulative incidence of CKD was about 15%. Our results showed that delayed-onset LN, acute renal dysfunction at the onset of LN, and inadequate treatment response assessed at 6 or 12 months after treatment were predictors for the development of CKD in LN. Key Points • CKD is a major risk factor for overall morbidity and mortality in LN patients. • Ten-year cumulative incidence of CKD was about 15% • Delayed-onset LN, acute renal dysfunction at the onset of LN, and inadequate treatment response assessed at 6 or 12 months after treatment were predictors for the development of CKD in LN., (© 2022. International League of Associations for Rheumatology (ILAR).)

Independent quality testing of samples from vaccine lots is part of quality assurance, especially to ensure the consistency of production lot by lot. Effective national lot release system that ensures the quality of each lot of vaccine before it is on the market is important because vaccines are intended to healthy people. In order to respond more quickly to public health crises such as the COVID-19 pandemic, the MFDS implements accelerated national lot release for rapid vaccination in Republic of Korea. For the accelerated system, improvement has been made in terms of timing of application for lot release and required documents. In addition, the processing period has been shortened and sampling method and test items have been streamlined. A thorough preparation for accelerated lot release has been developed by establishing test methods for a new platform in advance. As a result, a total of 43.88 million doses have been released within eight days on average. The accelerated lot release system has contributed significantly to rapid COVID-19 vaccination in Korea., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: CD4+ T cells are crucial for the pathogenesis of rheumatoid arthritis (RA). Here, we evaluated gene expression in CD4+ T cells in early RA, and main purpose of present study was to seek the changes in CD4+ T-cell-related cytokines according to RA progression., Methods: Early RA was defined as methotrexate (MTX)-naïve patients. Established RA was defined as patients with more than 6 months of DMARDs. Patients with osteoarthritis were evaluated as controls. Microarray analysis was used to identify overexpressed genes in CD4+ T cells, and RT-qPCR was used to validate. Plasma cytokine were measured in patients with early and established RA, and correlations with disease activity were assessed in patients with early RA, whereas clinical prognosis was assessed in established patients with RA., Results: Thirty-four genes showed overexpression in CD4+ T cells from patients with early RA compared with OA controls. Nineteen were related to interferon (IFN)-γ, and eight were related to interleukin (IL)-17A. Plasma levels of IL-17A, IL-6, IL-12, and TNF-α correlated with IFN-γ, and correlation coefficient was highest between DAS28-ESR and plasma IFN-γ levels in patients with early RA (Rho=0.553, p=0.0025). In established RA with low disease activity, drug reduction group showed lower plasma IFN-γ and IL-17A than drug maintenance/relapse group (13.61±5.75 vs. 29.89±18.72, p<0.001; and 10.91±3.92 vs. 21.04±12.81 pg/mL, p<0.001, respectively)., Conclusions: The IFN-γ and IL-17 gene signature in CD4+ T cells was significantly increased in early RA. Patients with established RA with low levels of IFN-γ and IL-17A could be eligible for dose reduction.

Post-inflammatory hyperpigmentation is a skin discoloration process that occurs following an inflammatory response or wound. As the skin begins to heal, macrophages first exhibit a proinflammatory phenotype (M1) during the early stages of tissue repair and then transition to a pro-healing, anti-inflammatory phenotype (M2) in later stages. During this process, M1 macrophages remove invading bacteria and M2 macrophages remodel surrounding tissue; however, the relationship between macrophages and pigmentation is unclear. In this study, we examined the effect of macrophages on melanin pigmentation using human induced pluripotent stem cells. Functional melanocytes were differentiated from human induced pluripotent stem cells and named as hiMels. The generated hiMels were then individually cocultured with M1 and M2 macrophages. Melanin synthesis decreased in hiMels cocultured with M1 macrophages but significantly increased in hiMels cocultured with M2 macrophages. Moreover, the expression of vascular endothelial growth factor was increased in M2 cocultured media. Our findings suggest that M2 macrophages, and not M1 macrophages, induce hyperpigmentation in scarred areas of the skin during tissue repair., (© 2022. The Author(s).)

Digital health is rapidly growing worldwide and its area is expanding from wellness to treatment due to digital therapeutics (DTx). This study compared DTx in the Korean context with other countries to better understand its political and practical implications. DTx is generally the same internationally, often categorized as software as a medical device. It provides evidence-based therapeutic interventions for medical disabilities and diseases. Abroad, DTx support entailed state subsidies and fundraising and national health insurance coverage. In the case of national health insurance coverage, most cases were applied to mental diseases. Moreover, in Japan, DTx related to hypertension will possibly be under discussion for national health insurance coverage in 2022. In overseas countries, coverage was decided only when the clinical effects were equivalent to those provided by existing technology, and in the UK, real usage data for DTx and associated evaluations were reflected by national health coverage determination. Prices were either determined through closed negotiations with health insurance operating agencies and manufacturers or established based on existing technology. Concerning the current situation, DTx dealing with various diseases including hypertension are expected to be developed near in the future, and the demand for use and compensation will likely increase. Therefore, it is urgent to define and prepare for DTx, relevant support systems, and health insurance coverage listings. Several support systems must be considered, including government subsidies, science/technology funds, and health insurance., Competing Interests: The authors have no financial conflicts of interest., (Copyright © 2022. The Korean Society of Cardiology.)

Alzheimer's disease (AD) is the most common condition in patients with dementia and affects a large population worldwide. The incidence of AD is expected to increase in future owing to the rapid expansion of the aged population globally. Researchers have shown that women are twice more likely to be affected by AD than men. This phenomenon has been attributed to the postmenopausal state, during which the level of estrogen declines significantly. Estrogen is known to alleviate neurotoxicity in the brain and protect neurons. While the effects of estrogen have been investigated in AD models, to our knowledge, they have not been investigated in a stem cell-based three-dimensional in vitro system. Here, we designed a new model for AD using induced pluripotent stem cells (iPSCs) in a three-dimensional, in vitro culture system. We used 5xFAD mice to confirm the potential of estrogen in alleviating the effects of AD pathogenesis. Next, we confirmed a similar trend in an AD model developed using iPSC-derived cerebral organoids, in which the key characteristics of AD were recapitulated. The findings emphasized the potential of estrogen as a treatment agent for AD and also showed the suitability of AD-recapitulating cerebral organoids as a reliable platform for disease modeling and drug screening., Competing Interests: JK and YN are employed by YiPSCELL, Inc. JHJ is founder of YiPSCELL, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kim, Mo, Kim, Kim, Nam, Rim and Ju.)

7S,15R-Dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA) and 7S,15R,16S,17S-tetrahydroxy-docosapentaenoic acid (TH-DPA) are two novel lipid mediators derived from docosahexaenoic acid (DHA) that we previously synthesized via combined enzymatic and chemical reactions. In the present study, we investigated the effects of these compounds on disturbances in lipid metabolism and liver inflammation induced by a high fat diet (HFD) in mice. Male BALB/c mice were randomly divided into four groups (n = 10/group): controls, HFD only, HFD + diHEP-DPA, and HFD + TH-DPA. Mice in HFD + diHEP-DPA and HFD + TH-DPA groups were orally administered 20 μg/kg of diHEP-DPA or TH-DPA, respectively. Measurements of adipose accumulation and liver inflammation showed that both diHEP-DPA and TH-DPA decreased adipose tissue mass and liver color depth, as well as total cholesterol, triglycerides, and low-density lipoprotein-cholesterol in the serum of HFD-fed mice compared with mice in the HFD-only group, while elevating high-density lipoprotein-cholesterol. Both of them also decreased hepatic expression of genes encoding lipid synthesis-related proteins (PPARγ, SIRT1, SREBP-1c and FASN) and increased the expression of genes encoding proteins involved in lipid degradation (PPARα and CPT-1) in the liver. Western blotting and quantitative RT-PCR confirmed that diHEP-DPA or TH-DPA administration modulated the expression of inflammation-related genes (TNF-α and IL-6) and inhibited activation of the NF-κB signaling pathway in livers of HFD-fed mice. Taken together, our data indicate that diHEP-DPA and TH-DPA ameliorate liver inflammation and inhibit HFD-induced obesity in mice., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Due to the global public health crisis caused by the coronavirus disease 2019 (COVID-19) pandemic, the importance of vaccine development has increased. In particular, a rapid supply of vaccines and prompt deployment of vaccination programs are essential to prevent and overcome the spread of COVID-19. As a part of the vaccine regulations, national lot release is regulated by the responsible authorities, and this process involves the assessment of the lot before a vaccine is marketed. A lot can be released for use when both summary protocol (SP) review and quality control testing are complete. Accelerated lot release is required to distribute COVID-19 vaccines in a timely manner. In order to expedite the process by simultaneously undertaking the verification of quality assessment and application for approval, it is necessary to prepare the test methods before marketing authorization. With the prolonged pandemic and controversies regarding the effectiveness of the COVID-19 vaccine against new variants, public interest for the development of a new vaccine are increasing. Domestic developers have raised the need to establish standard guidance on the requirements for developing COVID-19 vaccine. This paper presents considerations for quality control in the manufacturing process, test items, and SP content of viral vector vaccines.

In 2006, the induced pluripotent stem cell (iPSC) was presented to the world, paving the way for the development of a magnitude of novel therapeutic alternatives, addressing a diverse range of diseases. However, despite the immense cell therapy potential, relatively few clinical trials evaluating iPSC-technology have actually translated into interventional, clinically applied treatment regimens. Herein, our aim was to determine trends in globally conducted clinical trials involving iPSCs. Data were derived both from well-known registries recording clinical trials from across the globe, and databases from individual countries. Comparisons were firstly drawn between observational and interventional studies before the latter was further analyzed in terms of therapeutic and nontherapeutic trials. Our main observations included global distribution, purpose, target size, and types of disorder relevant to evaluated trials. In terms of nontherapeutic trials, the USA conducted the majority, a large average number of participants-187-was included in the trials, and studies on circulatory system disorders comprised a slightly higher proportion of total studies. Conversely, Japan was the frontrunner in terms of conducting therapeutic trials, and the average number of participants was much lower, at roughly 29. Disorders of the circulatory, as well as nervous and visual systems, were all studied in equal measure. This review highlights the impact that iPSC-based cell therapies can have, should development thereof gain more traction. We lastly considered a few companies that are actively utilizing iPSCs in the development of therapies for various diseases, for whom the global trends in clinical trials could become increasingly important., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objectives: To assess the efficacy of an endothelin receptor antagonist (ERA) and phosphodiesterase type5 inhibitors (PDE5is) for treating SSc-related digital ulcers (DUs)., Methods: This prospective, multicentre, observational cohort study recruited patients with active SSc-related DUs from 13 medical centres in South Korea. The primary outcome was time to cardinal ulcer (CU) healing. A secondary outcome was time to new DU occurrence. Patients were followed up 4, 8, 12 and 24 weeks after treatment initiation., Results: Sixty-three patients were analysed. Their mean age was 49.9 years (s.d. 11.4) and 49 were female. Twenty-eight had limited SSc. Forty-nine patients received ERA, 11 received a PDE5i (9 sildenafil, 1 udenafil and 1 tadalafil) and 3 received other medication. The hazard ratio (HR) for time to CU healing in the ERA group vs the PDE5i group was 0.75 (95% CI 0.35, 1.64; P = 0.47) in an unadjusted model and 0.80 (95% CI 0.36, 1.78; P = 0.59) in a model adjusted for age, sex, use of calcium channel blockers (CCBs), total DU number and initial CU area. The HR for new DU development in the ERA group vs the PDE5i group was 0.39 (95% CI 0.16, 0.93; P = 0.03) in an unadjusted model and 0.32 (95% CI 0.13, 0.81; P = 0.02) in an adjusted model. No patients receiving CCBs developed new DUs at 24 weeks., Conclusion: Time to CU healing is comparable for ERA and PDE5i. ERAs are more effective in reducing new DU occurrence than PDE5is. CCBs may be effective as a background medication., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Since their discovery in 2006, induced pluripotent stem cells (iPSCs) have shown promising potential, specifically because of their accessibility and plasticity. Hence, the clinical applicability of iPSCs was investigated in various fields of research. However, only a few iPSC studies pertaining to osteoarthritis (OA) have been performed so far, despite the high prevalence rate of degenerative joint disease. In this review, we discuss some of the most recent applications of iPSCs in disease modeling and the construction of 3D models in various fields, specifically focusing on osteoarthritis and OA-related conditions. Notably, we comprehensively reviewed the successful results of iPSC-derived disease models in recapitulating OA phenotypes for both OA and early-onset OA to encompass their broad etiology. Moreover, the latest publications with protocols that have used iPSCs to construct 3D models in recapitulating various conditions, particularly the OA environment, were further discussed. With the overall optimistic results seen in both fields, iPSCs are expected to be more widely used for OA disease modeling and 3D model construction, which could further expand OA drug screening, risk assessment, and therapeutic capabilities.

Background/aims: Tacrolimus has been used as an immunosuppressive agent in organ transplantation. Despite the therapeutic benefits, tacrolimus's use is limited due to its nephrotoxicity. To reduce tacrolimus nephrotoxicity, effective humanized experimental models may be helpful. Here, we modeled tacrolimus nephrotoxicity using kidney organoids derived from human inducible pluripotent stem cells (iPSCs) in vitro., Methods: Kidney organoids were differentiated from the CMC11 iPSC cell line, re-seeded in 96-well plates, and treated with tacrolimus at doses of 0, 30, or 60 μM for 24 hours. This in vitro model was compared to a mouse model of tacrolimus nephrotoxicity and the associated mechanisms were investigated., Results: The size of the kidney organoids and cell viability decreased in dose-dependent manners after treatment with tacrolimus. The number of tubular cells decreased with a loss of polarity, similar to the effects seen in mouse tacrolimus nephrotoxicity. Ultrastructural analysis showed numerous vacuoles in the proximal tubular cells of the kidney organoids treated with tacrolimus. Tacrolimus treatment induced oxidative stress and mitochondrial dysfunction, and autophagic activity was enhanced in the kidney organoids. Rapamycin, an autophagy inducer, accelerated cell death in the kidney organoid model of tacrolimus nephrotoxicity, which was attenuated by treatment with 3-methyladenine, an autophagy inhibitor. These findings indicate that the augmentation of autophagy by rapamycin treatment accelerated tacrolimus nephrotoxicity., Conclusion: Our data suggest that human kidney organoids are an effective in vitro model of tacrolimus nephrotoxicity and that autophagy plays a critical role in tacrolimus nephrotoxicity.

Objective: To evaluate the predictors of mortality, mortality rate, and causes of death in patients with lupus nephritis (LN) depending on final renal function., Methods: The cohort included 401 Korean patients diagnosed with LN between 1985 and 2019. We retrospectively analyzed the clinical and laboratory indices, treatment response, and the final renal function. The final renal function was defined by the last stable level of eGFR measured in an out-patient department more than 3 times before death occurred and was categorized into five groups depending on CKD stage., Results: The median follow-up time after the diagnosis of LN was 131 months. No difference in baseline demographic characteristics and laboratory findings was found except for the proportion of Hb less than 10 mg/dl and baseline eGFR ( p = 0.011 and 0.037). We found no significant differences in therapeutic parameters, but all the response parameters including treatment response at 6 months ( p = 0.004) and 12 months ( p = 0.004), time to remission ( p < 0.001), final renal response ( p < 0.001), and the final renal function ( p < 0.001) differed significantly between the two groups. In multivariate Cox proportional hazards analysis, the final renal function was an independent risk factor predicting mortality. The main causes of death were infection and SLE flare. Contrary to existing knowledge, SLE flare also triggered mortality in a few patients with LN progressed to end-stage renal disease (ESRD). Only two cases of mortality occurred in the kidney transplantation (KT) group ( n = 25) with a median follow-up period of 224 months. The overall mortality rates calculated using the Kaplan-Meier method were 6.8%, 10.3%, 19.7%, and 28.0% at 5, 10, 20, and 30 years, respectively., Conclusion: Renal function deterioration was an independent determinant of mortality in Korean patients with LN. SLE flare also caused mortality in patients with LN who required maintenance dialysis, suggesting the benefit of KT on lupus activity and survival.

Organic acids produced during the fermentation of lactic acid bacteria inhibit cellular growth and the production of 1,3-propanediol (1,3-PDO). Lactobacillus reuteri JH83, which has an increase of 18.6% in organic acid resistance, was obtained through electron beam irradiation mutagenesis irrelevant to the problem of genetically modified organisms. The maximum bioconversion of 1,3-PDO in fed-batch fermentation using pure glycerol by L. reuteri JH83 was 93.2 g/L at 72 h, and the productivity was 1.29 g/L·h, which achieved an increase by 34.6%, compared to that of the wild-type strain. In addition, the result of fed-batch fermentation for the production of 1,3-PDO using crude glycerol was not significantly different from that of pure glycerol. Additionally, transcriptome analysis confirmed changes in the expression levels of sucrose phosphorylase, which is a major facilitator superfamily transporter, and muramyl ligase family proteins, which protect lactic acid bacteria from various stressors, such as organic acids., (Copyright © 2021. Published by Elsevier Ltd.)

Rheumatoid arthritis (RA) is caused by prolonged periodic interactions between genetic, environmental, and immunologic factors. Posttranslational modifications (PTMs) such as citrullination, carbamylation, and acetylation are correlated with the pathogenesis of RA. PTM and cell death mechanisms such as apoptosis, autophagy, NETosis, leukotoxic hypercitrullination (LTH), and necrosis are related to each other and induce autoantigenicity. Certain microbial infections, such as those caused by P orphyromonas gingivalis , Aggregatibacter actinomycetemcomitans, and Prevotella copri , can induce autoantigens in RA. Anti-modified protein antibodies (AMPA) containing anti-citrullinated protein/peptide antibodies (ACPAs), anti-carbamylated protein (anti-CarP) antibodies, and anti-acetylated protein antibodies (AAPAs) play a role in pathogenesis as well as in prediction, diagnosis, and prognosis. Interestingly, smoking is correlated with both PTMs and AMPAs in the development of RA. However, there is lack of evidence that smoking induces the generation of AMPAs.

3D cell printing technology is in the spotlight for producing 3D tissue or organ constructs useful for various medical applications. In printing of neuromuscular tissue, a bioink satisfying all the requirements is a challenging issue. Gel integrity and motor neuron activity are two major characters because a harmonious combination of extracellular materials essential to motor neuron activity consists of disadvantages in mechanical properties. Here, a method for fabrication of 3D neuromuscular tissue is presented using a porcine central nervous system tissue decellularized extracellular matrix (CNSdECM) bioink. CNSdECM retains CNS tissue-specific extracellular molecules, provides rheological properties crucial for extrusion-based 3D cell printing, and reveals positive effects on the growth and maturity of axons of motor neurons compared with Matrigel. It also allows long-term cultivation of human-induced-pluripotent-stem-cell-derived lower motor neurons and sufficiently supports their cellular behavior to carry motor signals to muscle fibers. CNSdECM bioink holds great promise for producing a tissue-engineered motor system using 3D cell printing., (© 2021 Wiley-VCH GmbH.)

The pellet formation has been regarded as a golden standard for in vitro chondrogenic differentiation. However, a spatially inhomogeneous chondrogenic microenvironment around a pellet resulted from the use of a traditional impermeable narrow tube, such as the conical tube, undermines the differentiation performance and therapeutic potential of differentiated cartilage pellet in defective articular cartilage treatment. To address this drawback, a perichondrium-inspired permeable nanofibrous tube (PINaT) well with a nanofibrous wall permeable to gas and soluble molecules is proposed. The PINaT well was fabricated with a micro deep drawing process where a flat thin nanofibrous membrane was transformed to a 3.5 mm deep tube well with a ∼50 µ m thick nanofibrous wall. Similar to in vivo perichondrium, the PINaT well was found to allow oxygen and growth factor diffusion required for chondrogenic differentiation across the entire nanofibrous wall. Analyses of gene expressions (COL2A1, COL10A1, ACAN, and SOX9), proteins (type II and X collagen), and glycosaminoglycans contents were conducted to assess the differentiation performance and clinical efficacy of differentiated cartilage pellet. The regulated spatially homogeneous chondrogenic microenvironment around the human induced pluripotent stem cell-derived pellet (3 × 10 5 cells per pellet) in the PINaT well remarkably improved the quality of the differentiated pellet toward a more hyaline-like cartilage pellet. Furthermore, an accelerated chondrogenic differentiation process of the pellet produced by the PINaT well was achieved for 14 days, demonstrating a hyaline cartilage-specific marker similar to the control pellet differentiated for 20 days. Finally, the enhanced clinical efficacy of the hyaline-like cartilage pellet was confirmed using an osteochondral defect rat model, with the repaired tissue resembling hyaline cartilage rather than fibrous cartilage after 8 weeks of regeneration., (© 2021 IOP Publishing Ltd.)

Osteoporosis is commonly treated via the long-term usage of anti-osteoporotic agents; however, poor drug compliance and undesirable side effects limit their treatment efficacy. The parathyroid hormone-related protein (PTHrP) is essential for normal bone formation and remodeling; thus, may be used as an anti-osteoporotic agent. Here, we developed a platform for the delivery of a single peptide composed of two regions of the PTHrP protein (1-34 and 107-139); mcPTHrP 1-34+107-139 using a minicircle vector. We also transfected mcPTHrP 1-34+107-139 into human mesenchymal stem cells (MSCs) and generated Thru 1-34+107-139-producing engineered MSCs (eMSCs) as an alternative delivery system. Osteoporosis was induced in 12-week-old C57BL/6 female mice via ovariectomy. The ovariectomized (OVX) mice were then treated with the two systems; (1) mcPTHrP 1-34+107-139 was intravenously administered three times (once per week); (2) eMSCs were intraperitoneally administered twice (on weeks four and six). Compared with the control OVX mice, the mcPTHrP 1-34+107-139-treated group showed better trabecular bone structure quality, increased bone formation, and decreased bone resorption. Similar results were observed in the eMSCs-treated OVX mice. Altogether, these results provide experimental evidence to support the potential of delivering PTHrP 1-34+107-139 using the minicircle technology for the treatment of osteoporosis.

MXenes, an emerging class of two-dimensional (2D) transition metal carbides and nitrides, have attracted wide attention because of their fascinating properties required in functional electronics. Here, an atomic-switch-type artificial synapse fabricated on Ti 3 C 2 T x MXene nanosheets with lots of surface functional groups, which successfully mimics the dynamics of biological synapses, is reported. Through in-depth analysis by X-ray photoelectron spectroscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy, it is found that the synaptic dynamics originated from the gradual formation and annihilation of the conductive metallic filaments on the MXene surface with distributed functional groups. Subsequently, via training and inference tasks using a convolutional neural network for the Canadian-Institute-For-Advanced-Research-10 dataset, the applicability of the artificial MXene synapse to hardware neural networks is demonstrated., (© 2021 Wiley-VCH GmbH.)