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Managing type 1 diabetes mellitus (T1DM) presents significant challenges because of the complexity of replicating the microenvironment of pancreatic islets and ensuring the long-term viability and function of transplanted insulin-producing cells (IPCs). This study developed a functional approach that utilizes 3D bioprinting technology to create pore-enriched and pre-vascularized tissue constructs incorporating a pancreatic tissue-derived decellularized extracellular matrix and human-induced pluripotent stem cells (hiPSCs) aimed at enhancing blood glucose regulation in T1DM. We designed a volumetric 3D pancreatic tissue construct that supported the engraftment, survival, and insulin-producing functionality of hiPSC-derived IPCs. The construct's porosity was optimized to enhance IPC delivery efficiency. Additionally, human umbilical vein endothelial cells co-cultured with IPCs in a patterned structure facilitated pre-vascularization, improving construct integration with host tissues and accelerating revascularization post-transplantation. Our results demonstrate high cell viability and sustained insulin production in diabetic rodent models, indicating the constructs' effectiveness in regulating blood glucose levels over an extended period. The findings of this study not only underscore the potential of 3D bioprinting for creating functional tissue constructs for T1DM treatment but also offer efficient cell delivery techniques applicable to other areas of regenerative medicine., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

This study assessed the seasonal distribution and factors associated with PM 2.5 in nationwide subway stations in Korea. A total of 229,644 data points collected over one year were used to determine one-day PM 2.5 concentrations from 642 subway stations. The geometric mean of indoor PM 2.5 concentrations was 26.6 µg/m 3 . PM 2.5 concentrations were higher in the Seoul metropolitan area (SMA) compared to non-Seoul metropolitan areas (NSMA), with the highest level occurring in winter, followed by spring, fall, and summer, similar to the trend observed for outdoor PM 2.5 concentrations. In SMA, PM 2.5 concentrations were significantly associated with the operation year, number of air cleaners on platforms, and number of passengers. These findings may help in the development of national strategies for managing indoor PM 2.5 concentrations in subway stations, taking into account spatial and temporal factors., 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 © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: There is a lack of robust evidence on the efficacy of laparoscopic pancreatoduodenectomy compared to open surgery. This study was aimed to compare time to functional recovery (FR) between laparoscopic and open pancreatoduodenectomy., Materials and Methods: This pragmatic, multicenter, randomized controlled phase 3 trial was conducted in seven tertiary centers. Patients with periampullary tumors were randomized using a block design in a 1:1 ratio and stratified by pancreatic fistula risk. Participants were randomized to undergo open or laparoscopic pancreatoduodenectomy by expert pancreatic surgeons. The primary outcome was the time to FR, defined as the number of days until FR was achieved in all five domains. The secondary endpoints included perioperative and short-term oncological outcomes., Results: Between March 2019 and June 2022, 252 patients were randomly assigned to laparoscopic ( n =125) or open groups ( n =127). Primary outcomes were reported in 235 patients. The mean time to FR was shorter in laparoscopic group compared to the open group (7.7 vs. 9.0 days, P =0.03). Laparoscopic group exhibited a higher cumulative rate of FR compared to the open group (Hazard ratio,1.34; 95% CI, 1.03-1.74; P =0.02). Severe complications, R0 resection, the number of retrieved lymph nodes and short-term survival rates were comparable between the two groups., Conclusions: Laparoscopic pancreatoduodenectomy demonstrated modest advantages in FR time over open surgery for selected patients with experienced surgeons., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Research on islet replacement through the differentiation of functionally matured insulin-producing β-like cells for the treatment of diabetes presents a significant challenge. Neural signals in β cell differentiation significantly impact the pancreatic microenvironment in glucose metabolism, but they are not fully understood. In this study, isoproterenol, a β adrenoreceptor agonist, was introduced into pancreatic progenitor cells, derived from human pluripotent stem cells in vitro, undergoing endocrine differentiation, using 2-dimensional (2D) and 3-dimensional (3D) differentiation protocols. This resulted in increased insulin and C-peptide secretion, along with elevated expression of key pancreatic beta cell transcription factors, including PDX-1, NKX6.1, and MAFA, and improved function, demonstrated by increased responsiveness to glucose determined via a glucose-stimulated insulin secretion test. Moreover, RNA transcriptome analysis of isoproterenol-treated endocrine progenitors facilitated the identification of biological pathways and genes that contribute to mature beta cell differentiation efficiency correlated with neural signals, such as adrenoceptor beta 1, calcium/calmodulin dependent protein kinase II alpha, phospholipase C delta 4, and neurotrophic receptor tyrosine kinase 1. Among those genes, calcium/calmodulin dependent protein kinase II alpha was suggested as the most notable gene involved in the isoproterenol mechanism through inhibitor assays. This study illustrates that isoproterenol significantly enhances endocrine differentiation and underscores its effects on stem cell-derived beta cell maturation, emphasizing its therapeutic potential for the treatment of diabetes., 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 © 2024. Published by Elsevier Inc.)

Background: Islet transplantation is a recommended treatment for type 1 diabetes but is limited by donor organ shortage. This study introduces an innovative approach for improving the differentiation and functionality of insulin-producing cells (IPCs) from iPSCs using 3D spheroid formation and hydrogel matrix as an alternative pancreatic islet source. The extracellular matrix (ECM) is crucial for pancreatic islet functionality, but finding the ideal matrix for β-cell differentiation has been challenging. We aimed to advance IPC differentiation and maturation through an esterified collagen hydrogel, comparing its effectiveness with conventional basement membrane extract (BME) hydrogels., Methods: iPSCs were differentiated into IPCs using a small molecule-based sequential protocol, followed by spheroid formation in concave microwells. Rheological analysis, scanning electron microscopy, and proteomic profiling were used to characterize the chemical and physical properties of each matrix. IPCs, both in single-cell form and as spheroids, were embedded in either ionized collagen or BME hydrogels, which was followed by assessments of morphological changes, pancreatic islet-related gene expression, insulin secretion, and pathway activation using comprehensive analytical techniques., Results: Esterified collagen hydrogels markedly improved the structural integrity, insulin expression, and cell-cell interactions in IPC spheroids, forming densely packed insulin-expressing clusters, in contrast to the dispersed cells observed in BME cultures. Collagen hydrogel significantly enhanced the mRNA expression of crucial endocrine markers and maturation factors, with IPC spheroids showing accelerated differentiation from day 5, suggesting a faster differentiation compared to single cells in hydrogel encapsulation. Insulin secretion in response to glucose in collagen environments, with a GSIS index of 2.46 ± 0.05, exceeded those in 2D and BME, demonstrating superior pancreatic islet functionality. Pathway analysis highlighted enhanced insulin secretion capabilities, evidenced by the upregulation of genes like Secretogranin III and Chromogranin A in collagen cultures. In vivo transplantation results showed that collagen hydrogel enhanced cluster integrity, tissue integration, and insulin secretion compared to non-embedded IPCs and BME groups., Conclusion: Esterified collagen hydrogels demonstrated superior efficacy over 2D and BME in promoting IPC differentiation and maturation, possibly through upregulation of the expression of key secretion pathway genes. Our findings suggest that using collagen hydrogels presents a promising approach to enhance insulin secretion efficiency in differentiating pancreatic β-cells, advancing cell therapy in diabetes cell therapy., (© 2024. The Author(s).)

Underground shopping malls (USMs) are often open or semi-open environments with interconnected passageways, resulting in the sharing of indoor air. However, indoor air quality (IAQ) within these spaces can vary due to many diverse emission sources. We investigated the relationships between IAQ and geographical areas, as well as IAQ and store types, within USMs, in Korea. In 2020, we studied 10 different USMs, with a total of 128 outlets. We conducted comprehensive IAQ assessments (including measurements of fine particles (PM 2.5 ), aldehydes, and volatile organic compounds (VOCs)) in stores, passages, and outdoor areas. The stores were categorized into three types: clothing, fashion accessories, and food services. Additionally, we measured environmental factors such as CO 2 levels and presence of storefront walls. PM 2.5 levels were higher outdoors, whereas aldehyde and VOC levels exhibited elevations within passages and the interior of stores than in the outdoor environment. The store-to-passage ratios for PM 2.5 , individual aldehydes, and VOC concentrations ranged from 1.06 to 4.93. Formaldehyde and total VOC (TVOC) concentrations were found to be elevated in clothing and fashion accessory stores, whereas PM 2.5 concentrations were more prominent in food service establishments. Specific individual compounds, including propionaldehyde, hexaldehyde, benzene, n-heptane, toluene, n-octane, xylene, d-limonene, n-undecane, n-dodecane, and ethylbenzene concentrations exhibited associations with store types. Multivariate regression models demonstrated positive associations between most aldehydes and VOCs with CO 2 concentrations and presence of storefront walls. This study underscored variations within USMs based on area and store type. Aldehyde and VOC concentrations were notably higher in clothing and fashion accessory stores than in food service outlets; these elevations were closely linked to CO 2 levels and presence of storefront walls. These findings suggest that monitoring CO 2 levels within USM stores, optimizing air-conditioning systems, and designing future stores without storefront walls can collectively contribute to an overall improvement of IAQ within USMs., 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.)

Purpose: The purpose of this study was to determine whether the addition of decellularized bovine pericardial patch loaded with mesenchymal stromal cells enhanced bone-to-tendon healing and improved the biomechanical strength of large-to-massive rotator cuff tears in a small animal model., Methods: Adipose-derived mesenchymal stromal cells (MSCs) from rat inguinal fat were isolated, cultured, and loaded onto decellularized bovine pericardium patches. To simulate large-to-massive tears, rats were managed with free cage activity for 6 weeks after tear creation. A total of 18 rats were randomly allocated to repair-only (control), repair with pericardial patch augmentation (patch), or repair with MSC loaded pericardial patch augmentation (patch-MSC). Each group had 6 rats (one shoulder of each rat was used for histological evaluation and another for biomechanical evaluation). MSCs seeded on the pericardial patches were traced on four shoulders from 2 other rats at 4 weeks after surgery. Histological evaluation for bone-to-tendon healing and biomechanical testing was carried out at 8 weeks after repair., Results: MSCs tagged with a green fluorescent protein were observed in the repair site 4 weeks after the repair. One shoulder each in the control and patch groups showed complete discontinuity between the bone and tendon. One shoulder in the control group showed attenuation with only a tenuous connection. Fibrocartilage and tidemark formation at the bone-to-tendon interface (P = .002) and collagen fiber density (P = .040) and orientation (P = .003) were better in the patch-MSC group than in the control or patch group. Load-to-failure in the patch-MSC and patch groups was higher than that in the control group (P = .001 and .009, respectively)., Conclusion: Decellularized bovine pericardial patches loaded with adipose-derived and cultured mesenchymal stromal cells enhanced healing in terms of both histology and mechanical strength at 8 weeks following rotator cuff repair in a rat model., Clinical Relevance: Large-to-massive rotator tears need a strategy to prevent retear and enhance healing. The addition of decellularized bovine pericardial patch loaded with MSCs can enhance bone-to-tendon healing and improve biomechanical healing of large-to-massive rotator cuff tears following repair., (Copyright © 2022 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Isolating a large quantity of high-quality human islets is a prerequisite for diabetes research. Human islets are typically isolated from the pancreases of brain-dead donors, making research difficult due to low availability. Pancreas tissue discarded after surgical resection may be a good alternative source of islet cells. To test this hypothesis, we isolated islets from discarded surgical specimens and evaluated the islet yield and quality as well as islet cell preparations. Eighty-two segmental pancreases were processed using the Ricordi automated method, and islet yield and quality were investigated. The mean age of patients was 54.6, and the cohort included 32 diabetes patients. After purification, partially resected pancreases yielded an average of 59,593 ± 56,651 islet equivalents (IEQs) and 2546 IEQ/g of digested pancreas, with 71.5 ± 21% purity. Multivariate analysis revealed that diabetes ( p = 0.0046) and the lobe used ( p = 0.0156) significantly altered islet yield. Islets transplanted into diabetic mice displayed good viability and in vitro glucose responses, DNA/RNA quality, mitochondrial function, and glucose control, even though these results were dependent on islet quality. Isolated cells also maintained high viability and function even after cryopreservation. Our findings indicate that pancreatic tissue discarded after surgery can be a valuable source of islets for diabetes research.

Purpose: This study aimed (1) to confirm the maintenance of the extracellular vesicles (EVs) delivered via injectable collagen at the application site, and (2) to evaluate the effect of EVs derived from the human umbilical cord-derived mesenchymal stem cells and loaded in an injectable collagen gel after rotator cuff repair (RCR)., Methods: Rabbits (n = 20) were assigned to normal (N), repair-only (R), and those administered with injectable collagen after repair (RC), and EV-laden injectable collagen after repair (RCE) groups. The EVs isolated by ultra-centrifugation from the human umbilical cord-derived mesenchymal stem cells spent medium were mixed with collagen and administered accordingly. After 12 weeks, the rabbits were sacrificed to evaluate the healing of the bone-to-tendon junction and the fatty degeneration of muscle. Histomorphometric scoring for bone-tendon interface, fatty infiltration (%), and biomechanical tests were performed. Separately, groups of 3 rabbits were assigned to 3 different time points to evaluate maintenance of green fluorescence-labeled EVs with injectable collagen via tracking on the bursal side of the rotator cuff (3 groups: 3 days, 2, and 4 weeks)., Results: The EVs delivered by injectable collagen remained until 4 weeks at the bursal side of the cuff tissue. The RCE group showed a significantly greater histomorphometric total score (P < .001, and P = .013, respectively) and significantly lower fatty degeneration than the RC and R groups (P = .001, and P = .013, respectively). The biomechanical tests revealed significant growing trends in load-to-failure and stiffness (P = .002, and P = .013, respectively), in the R, RC, RCE, and N groups., Conclusions: EVs mounted in injectable collagen remained at the repair site for at least 4 weeks after application. Furthermore, they effectively promote bone-to-tendon healing via collagen maturation in bone-tendon interface and preventing fatty degeneration of rotator muscle after RCR as compared with collagen-only or repair-only groups., Clinical Relevance: The combination of collagen with EVs significantly promotes rotator cuff healing demonstrating potential clinical application during partial rotator cuff tear or after RCR., (Copyright © 2022 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Background: Although stem cells might enhance natural enthesis healing in surgical rotator cuff repair, not much attention has been given to the delivery and location of delivering stem cells. The purpose of this study to know where to locate those stem cells during repair., Methods: Animal model of chronic rotator cuff tear was created in 24 rats. Adipose-derived stem cells were engineered as a sheet and transplanted 1) between a torn tendon and humerus (interposition group) or 2) over a repaired tendon-to-bone junction (overlay group) at the time of surgical repair. Tracking of stem cells with overexpression of green fluorescent protein (GFP) were carried out at the time of sacrifice in additional 4 shoulders in each group. Histological and Biomechanical evaluation was performed to compare the differences in tendon-to-bone healing., Results: Histology showed increased fibrocartilage, a clear boundary at the mineralized fibrocartilage, abundant collagen type III, and higher total scores, especially in the interposition group. GFP-overexpression was observed at the transplanted site at 2 weeks after repair. Although two groups where stem cell sheets applied showed higher load to failure than the repair-only group, the load to failure was not different between the interposition and overlay group., Conclusion: In the chronic rotator cuff repair model, stem cell sheets enhanced regeneration of the tendon-to-bone junction. This regeneration was effective when the stem cell sheet was interpositioned at the tendon-to-bone interface., Level of Evidence: Basic Science Study; In Vivo Animal Model; Histology and Biomechanics., Competing Interests: The authors have declared that no competing interests exist.

Although pancreatic islet transplantation is a potentially curative treatment for insulin-dependent diabetes, a shortage of donor sources, low differentiation capacity, and transplantation efficacy are major hurdles to overcome before becoming a standard therapy. Stem cell-derived insulin-producing cells (IPCs) are a potential approach to overcoming these limitations. To improve the differentiation capacity of the IPCs, cell cluster formation is crucial to mimic the 3D structure of the islet. This study developed a biodegradable polycaprolactone (PCL) electrospun nanofibrous (NF) microwell-arrayed membrane permeable to soluble factors. Based on the numerical analysis and experimental diffusion test, the NF microwell could provide sufficient nutrients, unlike an impermeable PDMS (polydimethylsiloxane) microwell. The IPC clusters in the NF microwells showed higher gene expression of insulin and PDX1 and insulin secretion than the PDMS microwells. The IPC clusters in the NF microwell-arrayed membrane could be directly transplanted. Transplanted IPC clusters in the microwells survived well and expressed PDX1 and insulin. Additionally, human c-peptide was identified in the blood plasma at two months after transplantation of the membranes. The NF microwell-arrayed membrane can be a new platform promoting IPC differentiation capacity and realizing an in situ transplantation technique for diabetic patients.

With the aim of fabricating drug-loaded implantable patches, a 3D printing technique was employed to produce novel coaxial hydrogel patches. The core-section of these patches contained a dopamine-modified methacrylated alginate hydrogel loaded with a chemotherapeutic drug (Gemcitabine), while their shell section was solely comprised of a methacrylated alginate hydrogel. Subsequently, these patches were further modified with CaCO 3 cross linker and a polylactic acid (PLA) coating to facilitate prolonged release of the drug. Consequently, the results showed that addition of CaCO 3 to the formula enhanced the mechanical properties of the patches and significantly reduced their swelling ratio as compared to that for patches without CaCO 3 . Furthermore, addition of PLA coating to CaCO 3 -containing patches has further reduced their swelling ratio, which then significantly slowed down the release of Gemcitabine, to a point where 4-layered patches could release the drug over a period of 7 days in vitro. Remarkably, it was shown that 3-layered and 4-layered Gemcitabine loaded patches were successful in inhibiting pancreatic cancer cell growth for a period of 14 days when tested in vitro. Lastly, in vivo experiments showed that gemcitabine-loaded 4-layered patches were capable of reducing the tumor growth rate and caused no severe toxicity when tested in mice. Altogether, 3D printed hydrogel patches might be used as biocompatible implants for local delivery of drugs to diseased site, to either shrink the tumor or to prevent the tumor recurrence after resection.

Postoperative pancreatic fistula at the early stage can lead to auto-digestion, which may delay the recovery of the pancreaticojejunal (PJ) anastomosis. The efficacy and safety of an acetazolamide-eluting biodegradable tubular stent (AZ-BTS) for the prevention of self-digestion and intra-abdominal inflammatory diseases caused by pancreatic juice leakage after PJ anastomosis in a porcine model were investigated. The AZ-BTS was successfully fabricated using a multiple dip-coating process. Then, the drug amount and release profile were analyzed. The therapeutic effects of AZ were examined in vitro using two kinds of pancreatic cancer cell lines, AsPC-1 and PANC-1. The efficacy of AZ-BTS was assessed in a porcine PJ leakage model, with animals were each assigned to a leakage group, a BTS group and an AZ-BTS group. The overall mortality rates in these three groups were 44.4%, 16.6%, and 0%, respectively. Mean α-amylase concentrations were significantly higher in the leakage and BTS groups than in the AZ-BTS group on day 2-5 (p < 0.05 each all). The luminal diameters and areas of the pancreatic duct were significantly larger in the leakage group than in the BTS and AZ-BTS groups (p < 0.05 each all). These findings indicate that AZ-BTS can significantly suppress intra-abdominal inflammatory diseases caused by pancreatic juice leakage and also prevent late stricture formation at the PJ anastomotic site in a porcine model., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Although many indoor public places have implemented smoke-free regulations, private homes have remained sources of tobacco smoke pollutants. This study examined differences in urinary cotinine concentrations in the Korean non-smoking adult population between living in smoking and smoke-free homes, and the relationship of urinary cotinine concentrations with socio-demographic factors in smoke-free homes., Methods: Samples from 2575 non-smoking adults (≥19 years old) in the Korean National Environmental Health Survey cycle 3 (2015-2017), a representative Korean study, were used. Smoking and smoke-free homes were defined based on whether there were smokers at homes. Weighted linear regression models were used to determine urinary cotinine concentrations and identify factors associated with urinary cotinine., Results: The geometric mean of urinary cotinine concentrations for non-smoking adults living in smoking homes was 2.1 μg/L (95% confidence interval [CI] = 1.8-2.4), which was significantly higher than the mean of 1.3 μg/L (95% CI = 1.2-1.4) for those living in smoke-free homes. Urinary cotinine concentrations were different significantly by home smoking status in most socio-demographic subgroups. Data from smoke-free home showed urinary cotinine concentration in adults was significantly higher in those who lived in homes with ventilation duration < 30 min/day, those who spent more time indoors at home, those who spent less time outdoors, and those who worked in non-manual or manual occupations., Conclusions: The urinary cotinine concentration in Korean non-smoking adults living in smoking homes was higher than that in adults living in smoke-free homes. Even in smoke-free homes, home-related factors, such as ventilation duration and time spent indoors, were associated with urinary cotinine concentration. Further study is warranted to examine potential sources of tobacco smoke pollution in smoke-free homes.

Underground shopping districts (USDs) are susceptible to severe indoor air pollution, which can adversely impact human health. We measured 24 volatile organic compounds (VOCs) in 13 USDs throughout South Korea from July to October 2017, and the human risk of inhaling hazardous substances was evaluated. The sum of the concentrations of the 24 VOCs was much higher inside the USDs than in the open air. Based on factor analysis, six indoor air pollution sources were identified. Despite the expectation of a partial outdoor effect, the impacts of the indoor emissions were significant, resulting in an indoor/outdoor (I/O) ratio of 5.9 and indicating elevated indoor air pollution. However, the effects of indoor emissions decreased, and the contributions of the pollution sources reduced when the USD entrances were open and the stores were closed. Although benzene, formaldehyde, and acetaldehyde exhibited lower concentrations compared to previous studies, they still posed health risks in both indoor and outdoor settings. Particularly, while the indoor excess cancer risk (ECR) of formaldehyde was ~10 times higher than its outdoor ECR, benzene had a low I/O ratio (1.1) and a similar ECR value. Therefore, indoor VOC concentrations could be reduced by managing inputs of open air into USDs.

Objectives: Circumferential endoscopic submucosal dissection (ESD) for large lesions induces severe stricture, requiring subsequent treatment. We aimed to evaluate the efficacy of allogeneic epithelial cell sheet transplantation in preventing esophageal stricture after circumferential ESD in a porcine model., Materials and Methods: A total of 15 conventional pigs underwent a 4 cm long circumferential ESD in the mid-esophagus. Out of these animals, 11 were immediately subjected to allogeneic oral mucosal cell sheet transplantation at the resection site, whereas four pigs underwent circumferential ESD only. We performed upper endoscopy 1 and 2 weeks after ESD and assessed the degree of esophageal stricture and histologic characteristics., Results: Dysphagia scores and weight change ratios recorded 1 and 2 weeks after ESD did not differ between the two groups. The stricture rate 2 weeks after ESD was 100% in the control group and 90.9% in the cell sheet group ( p  = 1.000). The median mucosal constriction rates of the control and cell sheet groups were 73.5% (range 63.0-80.0%) and 53.8% (37.5-73.3%, p  = .018), respectively. With regard to microscopic measurements, the length of re-epithelialization was greater in the cell sheet group than in the control group (2,495 µm vs. 369 µm, p  = .008). Median fibrosis thickness and degree of muscle damage were not significantly different between groups., Conclusions: Although allogeneic epithelial cell sheet transplantation showed greater re-epithelialization and less mucosal constriction of post-ESD ulcers, it was not sufficiently effective in preventing post-ESD stricture.

Background: Although pancreatic islet transplantation therapy is ideal for diabetes patients, several hurdles have prevented it from becoming a standard treatment, including donor shortage and low engraftment efficacy. In this study, we prepared insulin-producing cells trans-differentiated from adult human liver cells as a new islet source. Also, cell sheet formation could improve differentiation efficiency and graft survival., Methods: Liver cells were expanded in vitro and trans-differentiated to IPCs using adenovirus vectors carrying human genes for PDX1, NEUROD1, and MAFA. IPCs were seeded on temperature-responsive culture dishes to form cell sheets. Differentiation efficiency was confirmed by ß cell-specific gene expression, insulin production, and immunohistochemistry. IPC suspension was injected by portal vein (PV), and IPC sheet was transplanted on the liver surface of the diabetic nude mouse. The therapeutic effect of IPC sheet was evaluated by comparing blood glucose control, weight gain, histological evaluation, and hepatotoxicity with IPC injection group. Also, cell biodistribution was assessed by in vivo/ex vivo fluorescence image tagging., Results: Insulin gene expression and protein production were significantly increased on IPC sheets compared with those in IPCs cultured on conventional culture dishes. Transplanted IPC sheets displayed significantly higher engraftment efficiency and fewer transplanted cells in other organs than injected IPCs, and also lower liver toxicity, improved blood glucose levels, and weight gain. Immunohistochemical analyses of liver tissue revealed positive staining for PDX1 and insulin at 1, 2, and 4 weeks after IPC transplantation., Conclusions: In conclusion, cell sheet formation enhanced the differentiation function and maturation of IPCs in vitro. Additionally, parameters for clinical application such as distribution, therapeutic efficacy, and toxicity were favorable. The cell sheet technique may be used with IPCs derived from various cell sources in clinical applications.

We measured PM 2.5 in 41 underground shopping districts (USDs) in the Seoul metropolitan area from June to November 2017, and associated 18 trace elements to determine the sources and assess the respiratory risks. The PM 2.5 concentrations were 18.0 ± 8.0 μg/m 3 inside USDs, which were lower than 25.2 ± 10.6 μg/m 3 outside. We identified five sources such as indoor miscellanea, soil dust, vehicle exhaust/cooking, coal combustion, and road/subway dust, using factor analysis. Almost 67% of the total trace element concentration resulted from soil dust. Soil dust contribution increased with the number of stores because of fugitive dust emissions due to an increase in passers-by. Vehicle exhaust/cooking contribution was higher when the entrances of the USDs were closed, whereas coal combustion contribution was higher when the entrances of the USDs were open. Although miscellanea and coal combustion contributions were 3.4% and 0.7%, respectively, among five elements with cancer risk, Cr and Ni were included in miscellanea, and Pb, Cd, and As were included in coal combustion. The excess cancer risk (ECR) was the highest at 67 × 10 -6 for Cr, and the ECR for Pb was lower than 10 -6 , a goal of the United States Environmental Protection Agency for hazardous air pollutants.

Pancreatic islet transplantation is the fundamental treatment for insulin-dependent diabetes; however, donor shortage is a major hurdle in its use as a standard treatment. Accordingly, differentiated insulin-producing cells (DIPCs) are being developed as a new islet source. Differentiation efficiency could be enhanced if the spheroid structure of the natural islets could be recapitulated. Here, we fabricated DIPC spheroids using concave microwells, which enabled large-scale production of spheroids of the desired size. We prepared DIPCs from human liver cells by trans-differentiation using transcription factor gene transduction. Islet-related gene expression and insulin secretion levels were higher in spheroids compared to those in single-cell DIPCs, whereas actin-myosin interactions significantly decreased. We verified actin-myosin-dependent insulin expression in single-cell DIPCs by using actin-myosin interaction inhibitors. Upon transplanting cells into the kidney capsule of diabetic mouse, blood glucose levels decreased to 200 mg/dL in spheroid-transplanted mice but not in single cell-transplanted mice. Spheroid-transplanted mice showed high engraftment efficiency in in vivo fluorescence imaging. These results demonstrated that spheroids fabricated using concave microwells enhanced the engraftment and functions of DIPCs via actin-myosin-mediated cytoskeletal changes. Our strategy potentially extends the clinical application of DIPCs for improved differentiation, glycemic control, and transplantation efficiency of islets.

Background: Efforts are being made to treat rotator cuff tears (RCTs) that exhibit poor healing and high retear rates. Tendon-to-bone healing using mesenchymal stem cells is being explored, but research is needed to establish effective delivery options., Purpose: To evaluate the effects of an adipose-derived stem cell (ADSC) sheet on mesenchymal stem cell delivery for tendon-to-bone healing of a chronic RCT in rats and to demonstrate that ADSC sheets enhance tendon-to-bone healing., Study Design: Controlled laboratory study., Methods: Mesenchymal stem cells were obtained from rat adipose tissue, and a cell sheet was prepared using a temperature-responsive dish. To evaluate the efficacy of stem cells produced in a sheet for the lesion, the experiment was conducted with 3 groups: repair group, cell sheet transplantation after repair group, and cell sheet-only group. Histological, biomechanical, and micro-computed tomography (micro-CT) results were compared among the groups., Results: Hematoxylin and eosin staining for histomorphological analysis revealed that the cell sheet transplantation after repair group (5.75 ± 0.95) showed statistically significant higher scores than the repair (2.75 ± 0.50) and cell sheet-only (3.25 ± 0.50) groups ( P < .001). On safranin O staining, the cell sheet transplantation after repair group (0.51 ± 0.04 mm 2 ) had a larger fibrocartilage area than the repair (0.31 ± 0.06 mm 2 ) and cell sheet-only (0.32 ± 0.03 mm 2 ) groups ( P = .001). On micro-CT, bone volume/total volume values were significantly higher in the cell sheet transplantation after repair group (23.98% ± 1.75%) than in the other groups ( P < .039); there was no significant difference in the other values. On the biomechanical test, the cell sheet transplantation after repair group (4 weeks after repair) showed significantly higher results than the other groups ( P < .005)., Conclusion: Our study shows that engineered stem cells are a clinically feasible stem cell delivery tool for rotator cuff repair., Clinical Relevance: This laboratory study provides evidence that ADSCs are effective in repairing RCTs, which are common sports injuries.

Islet cell transplantation is considered an ideal treatment for insulin-deficient diabetes, but implantation sites are limited and show low graft survival. Cell sheet technology and adipose-derived stem cells (ADSCs) can be useful tools for improving islet cell transplantation outcomes since both can increase implantation efficacy and graft survival. Herein, the optimal transplantation site in diabetic mice was investigated using islets and stem cell sheets. We constructed multi-layered cell sheets using rat/human islets and human ADSCs. Cell sheets were fabricated using temperature-responsive culture dishes. Islet/ADSC sheet (AI sheet) group showed higher viability and glucose-stimulated insulin secretion than islet-only group. Compared to islet transplantation alone, subcutaneous AI sheet transplantation showed better blood glucose control and CD31+ vascular traits. Because of the adhesive properties of cell sheets, AI sheets were easily applied on liver and peritoneal surfaces. Liver or peritoneal surface grafts showed better glucose control, weight gain, and intraperitoneal glucose tolerance test (IPGTT) profiles than subcutaneous site grafts using both rat and human islets. Stem cell sheets increased the therapeutic efficacy of islets in vivo because mesenchymal stem cells enhance islet function and induce neovascularization around transplanted islets. The liver and peritoneal surface can be used more effectively than the subcutaneous site in future clinical applications.

Background: Tearing and degeneration of the rotator cuff at the tendon-to-bone junction are common in adults aged ≥50 years. Few studies have reported on the relationship between estrogen and the rotator cuff enthesis. In addition to preventing bone loss, selective estrogen receptor modulators have been shown to improve tendon and muscle quality., Purpose: To evaluate the effects of raloxifene (RLX) and vitamin D on rotator cuff tendon-to-bone healing in a rat model., Study Design: Controlled laboratory study., Methods: A total of 29 female rats (58 shoulders) were assigned to 4 groups: (1) control group, (2) ovariectomy (OVX)-only group, (3) no RLX group (OVX and rotator cuff repair [RCR]), and (4) RLX group (OVX, RCR, and RLX). Rats that did not undergo rotator cuff tear (RCT) surgery were divided into the control and OVX-only groups according to OVX surgery. Rats that underwent RCT surgery and RCR were divided into the no RLX and RLX groups according to RLX and vitamin D administration. An estrogen-deficient state was induced by OVX at 12 weeks of age. Bone mineral density (BMD) and trabecular bone characteristics were measured by micro-computed tomography, and healing of the tendon-to-bone junction was evaluated by biomechanical testing, histomorphometry, and micro-magnetic resonance imaging (MRI)., Results: The mean final body weight (BW; 461.6 ± 47.3 g) of the OVX-only group was significantly higher and BMD (0.25 ± 0.07 g/cm 3 ) was significantly lower ( P < .001) than the mean final BW (338.5 ± 35.1 g) and BMD (0.48 ± 0.05 g/cm 3 ) of the control group. In contrast, the RLX group showed that the BW (369.6 ± 35.8 g) and BMD (0.41 ± 0.08 g/cm 3 ) were not significantly different from the control group. The RLX group had a significantly higher histomorphometric total score (8.50 ± 1.05) than the no RLX group (4.83 ± 2.48). On biomechanical testing, the RLX group (29.7 ± 9.1 N) showed a significantly higher load to failure than the no RLX group (19.4 ± 8.8 N). On micro-MRI, the RLX group had a more homogeneous low signal and tendon continuity than the no RLX group., Conclusion: The combination treatment of RLX and vitamin D prevented a decrease in local BMD (greater tuberosity of the proximal humerus) and enhanced tendon-to-bone healing of the rotator cuff in a rat model., Clinical Relevance: This study induced an estrogen-deficient state similar to the human postmenopausal state and used drugs that are actually being prescribed in a clinical situation.

Biopolymer-based hydrogels have emerged as promising platforms for drug delivery systems (DDSs) due to their inherent biocompatibility, tunable physical properties and controllable degradability. Yet, drug release in majority of these systems is solely contingent on diffusion of drug molecules through the hydrogel, which often leads to burst release of drugs from these systems. Herein, inspired by the chemistry of mussel adhesive proteins, a new generation of coaxial hydrogel fibers was developed that could simultaneously exert both affinity and diffusion control over the release of chemotherapeutic drugs. Specifically, dopamine-modified alginate hydrogel along with chemotherapeutic drugs (doxorubicin or gemcitabine) was used as the main core component to confer affinity-controlled release, while a methacrylated-alginate hydrogel was used as the shell composition to provide the controlled diffusion barrier. It was shown that our coaxial mussel-inspired biofibers yielded biocompatible hydrogel fibers (as indicated by comprehensive in vitro and in vivo experiments) with favourable properties including controlled swelling, and enhanced mechanical properties, when compared against single fibers made from unmodified alginate. Notably, it was observed that these coaxial fibers were capable of releasing the two drugs in a slower manner, when compared to single fibers made from pure alginate, which was partly attributed to stronger interactions of drugs with dopamine-modified alginate (the core element of coaxial fibers) as observed from zeta-potential measurements. It was further shown that these drug-loaded coaxial fibers had optimal anticancer activity both in vitro and in vivo using various pancreatic cancer cell lines. Most remarkably, drug loaded coaxial fibers, particularly doxorubicin-containing fibers, had higher anticancer effect in vivo compared to systemic injection of equivalent dosage of the drugs. Altogether, these biocompatible and robust hydrogel fibers may be further used as neoadjuvant or adjuvant therapies for controlled delivery of chemotherapeutic drugs locally to the tumor sites.

Objective: Esterified collagen (EC) can be functionalized with heparin to enhance islet graft stability. Growth factors secreted by human adipose-derived stem cells (hADSCs) can bind efficiently to EC-heparin (EC-Hep), which enhances revascularization and cell protection. We investigated the therapeutic potential of a combined heparin-esterified collagen-hADSC (HCA)-islet sheet to enhance islet engraftment., Research Design and Methods: This study was designed to assess the efficiency of using EC-Hep as a scaffold for subcutaneous islet transplantation in diabetic athymic mice. After the hADSC-cocultured islets were seeded in the EC-Hep scaffold, islet function was measured by glucose-stimulated insulin secretion test and growth factors in the culture supernatants were detected by protein array. Islet transplantation was performed in mice, and graft function and survival were monitored by measuring the blood glucose levels. β-Cell mass and vascular densities were assessed by immunohistochemistry., Results: The EC-Hep composite allowed sustained release of growth factors. Secretion of growth factors and islet functionality in the HCA-islet sheet were significantly increased compared with the control groups of islets alone or combined with native collagen. In vivo, stable long-term glucose control by the graft was achieved after subcutaneous transplantation of HCA-islet sheet due to enhanced capillary network formation around the sheet., Conclusions: The findings indicate the potential of the HCA-islet sheet to enhance islet revascularization and engraftment in a hADSC dose-dependent manner, following clinical islet transplantation for the treatment of diabetes mellitus., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Stricture of pancreatic-enteric anastomoses is a major late complication of a pancreaticoduodenectomy for the treatment of a periampullary tumor and can lead to exocrine and endocrine insufficiency such as malnutrition and diabetes mellitus. We investigated the safety and efficacy of a biodegradable tubular stent (BTS) for preventing a pancreaticojejunostomy (PJ) anastomotic stricture in both a rat and porcine model. The BTS was manufactured using a terpolymer comprising poly p-dioxanone, trimethylene carbonate, and glycolide. A cohort of 42 rats was randomized into 7 groups of 6 animals each after BTS placement into the duodenum for the biodegradation assay. A total of 12 pigs were randomized equally into a control and BTS placement group. The effectiveness of the BTS was assessed by comparing radiologic images with histologic results. Surgical procedures and/or BTS placements were technically successful in all animals. The median mass losses of the removed BTS samples from the rat duodenum were 2.1, 6.8, 11.2, 19.4, 26.1, and 56.8% at 1, 2, 3, 4, 6, and 8 weeks, respectively. The BTS had completely degraded at 12 weeks in the rats. In the porcine PJ model, the mean luminal diameter and area of the pancreatic duct in the control group was significantly larger than in the BTS group (all p < 0.05). BTS placement thus appears to be safe and effective procedure for the prevention of PJ anastomotic stricture. These devices have the potential to be used as a temporary stent placement to treat pancreatic-enteric anastomoses, but further investigations are required for optimization in human.

The transplantation of pancreatic islets is a promising treatment for patients who suffer from type 1 diabetes accompanied by hypoglycemia and secondary complications. However, islet transplantation still has several limitations such as the low viability of transplanted islets due to poor islet engraftment and hostile environments. In addition, the insulin-producing cells differentiated from human pluripotent stem cells have limited ability to secrete sufficient hormones that can regulate the blood glucose level; therefore, improving the maturation by culturing cells with proper microenvironmental cues is strongly required. In this article, we elucidate protocols for preparing a pancreatic tissue-derived decellularized extracellular matrix (pdECM) bioink to provide a beneficial microenvironment that can increase glucose sensitivity of pancreatic islets, followed by describing the processes for generating 3D pancreatic tissue constructs using a microextrusion-based bioprinting technique.

Type 1 diabetes mellitus (T1DM) is a form of diabetes that inhibits or halts insulin production in the pancreas. Although various therapeutic options are applied in clinical settings, not all patients are treatable with such methods due to the instability of the T1DM or the unawareness of hypoglycemia. Islet transplantation using a tissue engineering-based approach may mark a clinical significance, but finding ways to increase the function of islets in 3D constructs is a major challenge. In this study, we suggest pancreatic tissue-derived extracellular matrix as a potential candidate to recapitulate the native microenvironment in transplantable 3D pancreatic tissues. Notably, insulin secretion and the maturation of insulin-producing cells derived from human pluripotent stem cells were highly up-regulated when cultured in pdECM bioink. In addition, co-culture with human umbilical vein-derived endothelial cells decreased the central necrosis of islets under 3D culture conditions. Through the convergence of 3D cell printing technology, we validated the possibility of fabricating 3D constructs of a therapeutically applicable transplant size that can potentially be an allogeneic source of islets, such as patient-induced pluripotent stem cell-derived insulin-producing cells.

Background: Genetic reprogramming is a powerful method for altering cell properties and inducing differentiation. However, even if the same gene is reprogrammed, the results vary among cells. Therefore, a better possible strategy involves treating cells with factors that further stimulate differentiation while using stem cells with the same tissue origin. This study aimed to increase induction efficiency and insulin production in reprogrammed cells using a combination of factors that promote cell differentiation., Methods: Porcine pancreatic cells were cultured to obtain mesenchymal stem cells expressing pancreatic cell-specific markers through sequential passages. The characteristics of these cells were identified, and the M3 gene (Pdx1, Ngn3, MafA) was reprogrammed to induce differentiation into insulin-producing cells. Additionally, the differentiation efficiency of insulin-producing cells was compared by treating reprogrammed cells with a differentiation-promoting factor., Results: Mesenchymal stem cells isolated from porcine pancreatic tissues expressed exocrine cell markers, including amylase and cytokeratin 18, and most cells continuously expressed the beta cell transcription factors Ngn3 and NeuroD. Reprogramming of the M3 gene resulted in differentiation into insulin-producing cells. Moreover, significantly increased insulin and glucagon expressions were observed in the suitable induction medium, and the characteristic beta cell transcription factors Pdx1, Ngn3, and MafA were expressed at levels as high as those in pancreatic islet cells., Conclusions: Differentiation into insulin-producing cells represents an alternative therapy for insufficient pancreatic islet cells when treating diabetes. Therefore, cells with the characteristics of the target cell should be used to improve differentiation efficiency by creating an environment that promotes reprogramming and differentiation., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Mesoporous graphenes (MPGs) with interpenetrating porous networks are successfully obtained by the pyrolysis of composite gel consisting of graphite oxide (GO) and the amphiphilic triblock copolymer (Pluronic P123) under Ar atmosphere, wherein P123 is used as a soft-template. The as-prepared composite gel is obtained following self-assembly and freeze-drying. The obtained MPGs have high BET specific surface area (531-746 m2 g-1 and ink-bottle like pores with three dimensional interconnected network. Furthermore, the specific surface area and porous parameters such as pore volume, pore size, and pore size distribution of MPGs can be rationally controlled by regulating the initial mass ratio of P123 to GO. With the increase of P123 ratio, the average mesopore size is decreased from ∼16.4 nm to ∼9.5 nm, which is similar to the diameter size of P123 micelles. Also, the adsorption capacities of MPG-20 for 52 indoor air standard components (100 μg mL-1, Supelco) are compared with two different materials, namely commercial porous polymers (2,6-diphenyleneoxide) and reduced graphene oxide (RGO). The result shows that MPG-20 has significantly better adsorption capacity than RGO but also similar or slightly better than commercial porous polymer. The mesoporous structure and surface chemistry of MPGs were the most important factors for the enhancement of the adsorption efficiency for volatile organic compounds.

Owing to the recent progress in regenerative medicine technology, clinical trials that harnessed the regeneration and immune modulation potentiality of stem cells for treating IBD have shown promising results. We investigated the feasibility and utility of intraluminal endoscopic transplantation of rat MSC sheets in murine models of experimental colitis for targeted delivery of stem cells to lesions. We isolated adipose-derived mesenchymal stem cells (AD-MSC) and bone marrow-derived mesenchymal stem cells (BM-MSC) from EGFP-transgenic rats and fabricated the cells in sheet forms using temperature-responsive culture dishes. The MSC sheets were endoscopically transplanted to the inflamed area in electrocoagulation and DNBS colitis model. The effect of the transplantation was verified using endoscopic scoring and histological analysis. In the electrocoagulation model, the AD-MSC group showed significantly decreased ulcer size in the transplanted regions. In the DNBS colitis model, the AD-MSC group showed decreased inflammation and colitis in the transplanted regions. Histologic analysis showed that the MSC sheets had successfully attached to the inflamed mucosa in both the electrocoagulation and DNBS colitis model. Our results show that endoscopic transplantation of MSC sheets could be a new effective mode of stem cell therapy for IBD treatment.

Post-operative pancreatic fistula (POPF) following pancreatic resection is a life-threatening surgical complication. Cell sheets were prepared and harvested using temperature-responsive culture dishes and transplanted as patches to seal POPF. Two different mesenchymal stem cell (MSC) sheets were compared in terms of the preventative ability for pancreatic leakage in a rat model. Both rat adipose-derived stem cell (rADSC) and bone marrow-derived stem cell (rBMSC) sheets were transplanted. Those rADSC and rBMSC sheets are created without enzymes and thus maintained their cell-cell junctions and adhesion proteins with intact fibronectin on the basal side, as well as characteristics of MSCs. The rats with post-pancreatectomy rADSC- or rBMSC-sheet patches had significantly decreased abdominal fluid leakage compared with the control group, demonstrated by MR image analysis and measurement of the volume of abdominal fluid. Amylase level was significantly lower in the rats with rADSC-sheet and rBMSC-sheet patches compared with the control groups. The rADSC sheet patches had increased adhesive and immune-cytokine profiles (ICAM-1, L-selectin, TIMP-1), and the rBMSC sheets had reduced immune reactions compared to the control. This is first project looking at the feasibility of tissue engineering therapy using MSC-sheets as tissue patches preventing leakage of abdominal fluid caused by POPF.

Tumors from 25 patients with pancreatic cancer were used to establish two patient-derived xenograft (PDX) models: orthotopic PDX (PDOX) and heterotopic (subcutaneous) PDX (PDHX). We compared gene expression by immunohistochemistry, single-nucleotide polymorphism (SNP), DNA methylation, and metabolite levels. The 4 cases, of the total of 13 in which simultaneous PDHX & PDOX models were established, were randomly selected. The molecular-genetic characteristics of the patient's tumor were well maintained in the two PDX models. SNP analysis demonstrated that both groups were more than 90% identical to the original patient's tumor, and there was little difference between the two models. DNA methylation of most genes was similar among the two models and the original patients tumor, but some gene sets were hypermethylated the in PDOX model and hypomethylated in the PDHX model. Most of the metabolites had a similar pattern to those of the original patient tumor in both PDX tumor models, but some metabolites were more prominent in the PDOX and PDHX models. This is the first simultaneous molecular-genetic and metabolite comparison of patient tumors and their tumors established in PDOX and PDHX models. The results indicate high fidelity of these critical properties of the patient tumors in the two models., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest related to this work.

Pancreatic cancer has a high rate of local recurrence and poor prognosis even with adjuvant chemotherapy after curative resection. The aim of this study was to investigate if local drug delivery combined with low dose systemic chemotherapy can increase the therapeutic effect of chemotherapy while reducing systemic toxicities. Poly-L-lactic acid-based 5-FU releasing patch was fabricated by electrospinning, and its tumour killing effects were first confirmed in vitro. The 5-FU patch directly adhered to the tumour in subcutaneous and orthotopic murine models, and induced a significant decrease in tumour size. Systemic gemcitabine treatment group, 5-FU drug releasing patch group, and systemic gemcitabine plus 5-FU patch group were compared by tumour size measurement, non-invasive bio-imaging, and histology in subcutaneous models. Combination of local drug patch and systemic chemotherapy led to increased tumour suppression effects that lasted longer, as well as increased survival rate. Histology revealed higher degree of apoptosis in the combined group. Systemic toxicity was recovered within 7 days after the treatment in all mice. Conclusively, local drug delivery using biocompatible polymer patch significantly inhibited tumour growth, and combination with systemic chemotherapy was more effective than single systemic chemotherapy.

Background: This study investigated the effects of mesenchymal stem cell (MSC) sheet transplantation on healing of chemically induced oral ulceration in a rabbit animal model., Methods: Oral mucosal ulcers were induced by topical application of filter paper soaked with 70% acetic acid to the anterior gingiva and buccal mucosa of 12 New Zealand white rabbits. The animals were randomly assigned to two groups: with (treatment group, n = 6) or without (control group, n = 6) cell sheets applied to ulcers. Gross findings were sequentially evaluated, and histologic examination was performed on day 7., Results: Based on gross inspection, ulceration resolved before day 5 in the treatment group; however, in the control group, healing was incomplete on day 7. In the treatment group, the total area of the ulcer decreased significantly from day 2 to day 5 (P < 0.001) and from day 5 to day 7 (P = 0.020), whereas the area decreased significantly from day 5 to day 7 in the control group (P < 0.001). Histologic and immunofluorescence examination revealed full-thickness mucosa healing and complete basal cell coverage in the treatment group; in contrast, only partial healing was observed on day 7 in the control group., Conclusions: Cell sheet technology using MSC can be an alternative treatment for oral ulcerations in that it can decrease healing time without invasive properties., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

To obtain improved efficacy against pancreatic cancer, we investigated the efficacy and safety of a locally-applied 5-fluorouracil (5-FU)-loaded polymeric patch on pancreatic tumors in an orthotopic nude-mouse model. The 5-FU-releasing polymeric patch was produced by 3D printing. After application of the patch, it released the drug slowly for 4 weeks, and suppressed BxPC-3 pancreas cancer growth. Luciferase imaging of BxPC3-Luc cells implanted in the pancreas was performed longitudinally. The drug patch delivered a 30.2 times higher level of 5-FU than an intra-peritoneal (i.p.) bolus injection on day-1. High 5-FU levels were accumulated within one week by the patch. Four groups were compared for efficacy of 5-FU. Drug-free patch as a negative control (Group I); 30% 5-FU-loaded patch (4.8 mg) (Group II); 5-FU i.p. once (4.8 mg) (Group III); 5-FU i.p. once a week (1.2 mg), three times (Group IV). The tumor growth rate was significantly faster in Group I than Group II, III, IV (p=0.047 at day-8, p=0.022 at day-12, p=0.002 at day-18 and p=0.034 at day-21). All mice in Group III died of drug toxicity within two weeks after injection. Group II showed more effective suppression of tumor growth than Group IV (p=0.018 at day-12 and p=0.017 at day-21). Histological analysis showed extensive apoptosis in the TUNEL assay and by Ki -67 staining. Western blotting confirmed strong expression of cleaved caspase-3 in Group II. No significant changes were found hematologically and histologically in the liver, kidney and spleen in Groups I, II, IV but were found in Group III.

Objectives: The objective of this study was to investigate the role of genetic status of DPC4 in recurrence patterns of resected pancreatic ductal adenocarcinoma (PDAC)., Methods: Between April 2004 and December 2011, data on patients undergoing surgical resection for PDAC were reviewed. Genetic status of DPC4 was determined and correlated to recurrence patterns and clinical outcomes., Results: Analysis of 641 patients revealed that genetic status of DPC4 was associated with overall survival and was highly correlated with recurrence patterns, as inactivation of the DPC4 gene was the strongest predictor of metastatic recurrence (odds ratio = 4.28). Treatment modalities for recurrent PDAC included chemotherapy alone and concurrent chemotherapy along with local control. For both locoregional and metastatic recurrence, local control resulted in improved survival; however, for groups subdivided according to recurrence patterns and genetic status of DPC4, local control contributed to improved survival in locoregional recurrences of patients with expressed DPC4, while chemotherapy alone was sufficient for others., Conclusions: Genetic status of DPC4 contributes to the recurrence patterns following pancreatectomy, and patients with an initially expressed DPC4 gene receive a greater benefit from intensive local control for locoregional recurrence. The DPC4 gene, therefore, may aid the establishment of treatment strategies for initial adjuvant treatment or for recurrent PDAC.

BACKGROUND The potential role of tissue damage factor high-mobility group box 1 (HMGB1) in islet cell transplantation is poorly understood. We investigated the role of HMGB1 in pancreatic islet cell isolation and culture in vitro and after pancreatic islet cell transplantation into diabetic nude mice in vivo. MATERIAL AND METHODS To generate damaged islets, isolated islets were treated with 1 mg/mL lipopolysaccharide (LPS). Some islets were pretreated with a neutralizing anti-HMGB1 antibody before LPS treatment to investigate the effect of HMGB1 on isolated islets damaged by LPS. Cell viability and insulin secretory function were analyzed 48 h after LPS and anti-HMGB1 antibody treatment. Streptozotocin-induced diabetes mice were injected with an anti-HMGB1 antibody 1 h prior to transplantation as a marginal islet mass. After transplantation, blood glucose levels were measured. RESULTS HMGB1 was more abundant in isolated islets than in other tissues, including pancreatic tissue. Anti-HMGB1 antibody pretreatment in LPS-treated islets improved cell viability and insulin secretory function and reduced the production of TNF-α and IL-1β. Streptozotocin-induced diabetic mice treated with an anti-HMGB1 antibody after marginal mass islet cell transplantation recovered to normal blood glucose levels more rapidly and maintained their euglycemic status compared to controls. CONCLUSIONS HMGB1 plays a significant role in early loss of transplanted islet cells. Based on these results, the development of new drugs that inhibit HMGB1 secretion could improve the efficacy and efficiency of clinical islet cell transplantation.

Background: Collagen exhibits ideal multifactorial action for preventing tissue adhesions. This study examined the efficacy of ionized collagen in preventing tissue adhesion after surgical procedures., Materials and Method: Ionized collagen was prepared using the esterification technique of natural collagen. Three forms of collagen materials (membrane, film, and gel) were compared with three commercialized materials (oxidized regenerated cellulose membrane [OC membrane], hyaluronic acid and carboxymethylcellulose film, and gel [HC film and HC gel]) in a rat cecum abrasion model. Antiadhesive activity and histologic findings were assessed., Result: The incidence of adhesion was reduced significantly in all test groups compared to the sham-operated control group (100% in control, 14.3% in collagen membrane, 63.6% in collagen film, 25.0% in collagen gel, 55.6% in OC membrane, 75% in HC film, and 83.3% in HC gel). All collagen materials of the three forms exhibited a significant reduction in adhesion grade compared with the sham operation, whereas no significant difference was found among these three different forms. The collagen membrane showed significantly less adhesion grade, less inflammation and more regenerative features compared to widely used conventional materials., Conclusions: This preclinical investigation indicated that ionized collagen materials readily formed clinically suitable shapes for easy handling without the need for any complex processing and effectively reduced postoperative tissue adhesion profiles compared to conventional antiadhesive agents., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Since recurrence and metastasis of pancreatic cancer has a worse prognosis, chemotherapy has been typically performed to attack the remained malignant cells after resection. However, it is difficult to achieve the therapeutic concentration at the tumor site with systemic chemotherapy. Numerous local drug delivery systems have been studied to overcome the shortcomings of systemic delivery. However, because most systems involve dissolution of the drug within the carrier, the concentration of the drug is limited to the saturation solubility, and consequently cannot reach the sufficient drug dose. Therefore, we hypothesized that 3D printing of a biodegradable patch incorporated with a high drug concentration would provide a versatile shape to be administered at the exact tumor site as well as an appropriate therapeutic drug concentration with a controlled release. Here, we introduce the 3D-printed patches composed of a blend of poly(lactide-co-glycolide), polycaprolactone, and 5-fluorouracil for delivering the anti-cancer drug in a prolonged controlled manner and therapeutic dose. 3D printing technology can manipulate the geometry of the patch and the drug release kinetics. The patches were flexible, and released the drug over four weeks, and thereby suppressed growth of the subcutaneous pancreatic cancer xenografts in mice with minimized side effects. Our approach reveals that 3D printing of bioabsorbable implants containing anti-cancer drugs could be a powerful method for an effective local delivery of chemotherapeutic agents to treatment of cancers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: To effectively use pancreatic cancer patient-derived xenograft (PDX) models in translational research, successful PDX engraftment of surgical specimens in immune-deficient mice is needed., Materials and Methods: A total of 102 patients underwent pancreatic cancer resection using various procedures. Tumor tissue from all patents was implanted subcutaneously into mice. Tumor engraftment and growth in mice were determined. Engraftment was tested for correlation with operation type, time, tumor size, and oncogene expression using immunohistoculture., Results: Multivariate analysis showed that a tumor size of more than 3.5 cm in the patient was a significant factor related to successful PDX engraftment. In contrast, there was no correlation of engraftment with surgical procedure, time needed to remove the specimen, tumor differentiation, lymph node metastasis, and protein expression of p53, Receptor tyrosine-protein kinase erbB-2 (CERBB2), or deleted in pancreatic carcinoma locus 4 (DPC4)., Conclusion: A minimum tumor size in the patient is an important factor for successful tumor engraftment., (Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Objectives: Glucose homeostasis changes after pancreatic resection are not well understood. We aimed to identify the incidence of, and risk factors for, a change in glucose homeostasis in patients who underwent pancreatectomy for benign pancreatic tumors., Methods: Clinical and pathological data from 229 patients were collected prospectively and analyzed retrospectively. The pancreas resection volume was calculated by computed tomography volumetry., Results: After pancreatectomy, newly diagnosed diabetes mellitus (DM) occurred in 52 patients (22.7%) and impaired fasting glucose and impaired glucose tolerance occurred in 74 patients (32.3%). The incidence of DM was highest for patients who underwent distal pancreatectomy (DP) (30.5%). Patients in the DP group had a significantly increased rate of DM as the pancreatic resection volume (in milliliters) and resected volume ratio (in percent) increased. A high body mass index and older age were significant risk factors for the development of DM by multivariate analysis., Conclusions: The resection volume of the pancreas is associated with a change in glucose homeostasis after pancreatectomy. Therefore, preservation of the pancreatic parenchyma is important to minimize the onset of DM in patients with a high pancreatic resected volume ratio (>35.6%) in DP, a high body mass index, or in old age.

Collagen, one of the most important components of the extracellular matrix (ECM), may play a role in the survival of pancreatic islet cells. In addition, chemical modifications that change the collagen charge profile to a net positive charge by esterification have been shown to increase the adhesion and proliferation of various cell types. The purpose of this study was to characterize and compare the effects of native collagen (NC) and esterified collagen (EC) on β cell function and survival. After isolation by the collagenase digestion technique, rat islets were cultured with NC and EC in 2 dimensional (2D) and 3 dimensional (3D) environments for a long-term duration in vitro. The cells were assessed for islet adhesion, morphology, viability, glucose-induced insulin secretion, and mRNA expression of glucose metabolism-related genes, and visualized by scanning electron microscopy (SEM). Islet cells attached tightly in the NC group, but islet cell viability was similar in both the NC and EC groups. Glucose-stimulated insulin secretion was higher in the EC group than in the NC group in both 2D and 3D culture. Furthermore, the mRNA expression levels of glucokinase in the EC group were higher than those in the NC group and were associated with glucose metabolism and insulin secretion. Finally, SEM observation confirmed that islets had more intact component cells on EC sponges than on NC sponges. These results indicate that modification of collagen may offer opportunities to improve function and viability of islet cells., (Copyright © 2015 Elsevier Inc. All rights reserved.)

This study aimed to investigate the effects of gender on the association between epicardial fat thickness (EFT) and circadian blood pressure (BP) changes in patients with recently diagnosed essential hypertension (EH). A total of 441 patients with EH (male/female: 236/205, mean age: 50.7 ± 13.8) and 83 control patients underwent 24-hour ambulatory BP monitoring and echocardiography. Obese EH patients had higher circadian BP profile with BP variability, wall thickness, and left ventricular mass than nonobese EH patients and controls (all p's <0.05) without gender differences. EFT was higher in female than in male patients (7.0 ± 2.5 versus 5.9 ± 2.2 mm, p < 0.001) and higher in the obese female EH group (7.5 ± 2.6 mm) than in the control (6.4 ± 2.8 mm) or nonobese EH group (6.7 ± 2.8 mm) among women, whereas EFT did not vary among males (5.9 ± 1.9 versus 6.0 ± 2.7 versus 5.9 ± 2.4 mm, p = 0.937). Multivariate logistic regression analysis demonstrated that the 24-hour mean BP variability was associated with SBP (p = 0.018) and EFT (p = 0.016) in female patients, but not in male patients. The relationships among circadian BP variability, obesity, and EFT were affected by gender in different manners. EFT may be a more valuable parameter in the evaluation of BP severity and obesity in women than in men.

Statins, 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors, are associated with the prevention of atrial fibrillation (AF) by pleiotropic effects. Recent clinical trial studies have demonstrated conflicting results on anti-arrhythmia between lipophilic and hydrophilic statins. However, the underlying mechanisms responsible for anti-arrhythmogenic effects of statins are largely unexplored. In this study, we evaluated the different roles of lipophilic and hydrophilic statins (simvastatin and pravastatin, respectively) in acetylcholine (100 µM)-activated K+ current (IKACh, recorded by nystatin-perforated whole cell patch clamp technique) which are important for AF initiation and maintenance in mouse atrial cardiomyocytes. Our results showed that simvastatin (1-10 µM) inhibited both peak and quasi-steady-state IKACh in a dose-dependent manner. In contrast, pravastatin (10 µM) had no effect on IKACh. Supplementation of substrates for the synthesis of cholesterol (mevalonate, geranylgeranyl pyrophosphate or farnesyl pyrophosphate) did not reverse the effect of simvastatin on IKACh, suggesting a cholesterol-independent effect on IKACh. Furthermore, supplementation of phosphatidylinositol 4,5-bisphosphate, extracellular perfusion of phospholipase C inhibitor or a protein kinase C (PKC) inhibitor had no effect on the inhibitory activity of simvastatin on IKACh. Simvastatin also inhibits adenosine activated IKACh, however, simvastatin does not inhibit IKACh after activated by intracellular loading of GTP gamma S. Importantly, shortening of the action potential duration by acetylcholine was restored by simvastatin but not by pravastatin. Together, these findings demonstrate that lipophilic statins but not hydrophilic statins attenuate IKACh in atrial cardiomyocytes via a mechanism that is independent of cholesterol synthesis or PKC pathway, but may be via the blockade of acetylcholine binding site. Our results may provide important background information for the use of statins in patients with AF.

Efficient osseointegration is a key factor in dental implants to reduce the total time-course of therapy. Titanium implants with anodized surface gained much interest for their enhanced osseointegration. Anodized implant combined with bioactive drugs is an ideal candidate for enhance bone regeneration. Previously delivery of drugs from the metal implants has been attempted by utilizing a polymeric dip-coating method. However, the entire surface coating with polymer can diminish the advantageous surface roughness of anodized implants and cause contact inhibition between bone and implant surface. In this study, fibroblast growth factor-2 (FGF-2) loaded poly(lactide-co-glycolide) nanoparticles were partially coated on anodized Ti discs by an electrospray deposition. Nanoparticle coated anodized discs maintained their native porous structure and provided a sustained release of FGF-2 for more than 2 weeks with 40% initial burst. In vitro study confirmed the influence of polymeric nanoparticles and the release of growth factors from the Ti disc. Nanoparticle-coated groups significantly enhanced cell spreading and differentiation. For in vivo evaluation, the anodized titanium implants were applied to rabbit tibia model. The osseointegration was estimated by bone to implant contact of best three consecutive threads at the border of the implant. The mean osteointegration value of FGF-2 releasing implant groups (70.1%) was significantly higher than that of untreated implants (47.1%). We believe that the electrospray deposition technique is a particularly attractive approach for the coating of medical devices with porous surface to maintain their surface topography while allowing a sustained delivery of growth factors for bone regeneration. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3639-3648, 2014., (© 2013 Wiley Periodicals, Inc.)

Intense haemostatic interventions are required to avoid bleeding complications when surgical procedures are performed on haemophilia patients. The objective of this study was to establish an appropriate protocol for perioperative haemostatic management of haemophilic mice. We assessed the prophylactic haemostatic effects of normal mouse plasma (NMP) on haemophilia B (HB) mice for both a skin flap procedure and a laparotomy. When 500 μL of NMP was administered to the mice, plasma factor IX (FIX:C) levels peaked at 15.1% immediately after intravenous (IV) administration, at 6.1% 2 h after intraperitoneal (IP) administration and at 2.7% 6 h after subcutaneous administration. Administering 500 μL of NMP via IP or IV 30 min in advance enabled the skin flap procedure to be performed safely without any complications. After the laparotomy procedure, several mice in the IP administration group exhibited lethal bleeding, but all mice survived in the IV administration group. Anti-mouse FIX inhibitors did not develop, even after repetitive administrations of NMP. However, human FIX concentrates, especially plasma-derived concentrates, elicited the anti-human FIX inhibitors. The results show that administering 500 μL of NMP via IV or IP 30 min in advance enables surgical procedures to be safely performed on HB mice, and that IV administration is more desirable than IP if the procedure requires opening of the abdominal wall., (© 2013 John Wiley & Sons Ltd.)

Takotsubo cardiomyopathy, which is also known as "transient apical ballooning", is a cardiac syndrome associated with emotional and physical stress that occurs in postmenopausal women. It may mimic acute coronary syndrome but coronary angiography reveals normal epicardial coronary arteries. The prognosis is favorable with the normalization of wall motion abnormalities within weeks. We report a case of persistent apical ballooning complicated by an apical thrombus in Takotsubo cardiomyopathy of systemic lupus erythematous patient. Takotsubo cardiomyopathy may not be always transient and left ventricular thrombus can occur in the disease course as our patient.