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Rationale: The current understanding of human lung development derives mostly from animal studies. While transcript-level studies have analyzed human donor tissue to identify genes expressed during...

The worldwide pandemic outbreak due to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has created unprecedented challenges for public health services. Lombardy, region of the Northern Italy, has been the first area in the Western world whose organs and tissues procurement programs have had to face the virus pandemic emergency. We retrospectively collected and analyzed data about cardiovascular tissues (CT) in 2019 and in 2020. We aimed to describe the rapid evolution of SARS-CoV-2 regulation laws for tissue donor’s selection and harvesting from February 2020 until January 2021. As expected the number of CT donors in 2020 was significantly lower than those of 2019 (66 vs. 99, p value 0.02). The total number of CT collected from donors have been 254 in 2019 and 206 in 2020 (p 0.28). Femoral arteries were the most required vascular tissues (55.5% in 2019 and 40% in 2020). Fifty-five and forty-eight pulmonary valves were implanted in 2019 and 2020, respectively. No differences were found for the types of CT requests between the 2 years. The median age of receivers of vascular tissues was 69.6 ± 14.6 years in the 2019 and 63.3 ± 14.9 years in 2020 (p

Objetivo: Desvelar as fragilidades e a vivência de enfermeiros na abordagem de famí­lia do doador de órgãos e tecidos. Método: Pesquisa de abordagem qualitativa com análise de conteúdo de Bardin, realizada com sete enfermeiros em um hospital de médio porte no interior de São Paulo, Brasil. Resultado: Os dados obtidos foram agrupados em três categorias centrais: Conhecimento dos enfermeiros no contexto da abordagem familiar do potencial doador de órgãos e tecidos; Fragilidades vivenciadas por enfermeiros no contexto da comunicação de más notí­cias para familiares do potencial doador de órgãos e tecidos e Experiências de enfermeiros diante do diagnóstico de morte encefálica e dos fatores determinantes para obtenção de órgãos e tecidos. Conclusão: As experiências dos enfermeiros frente, í s fragilidades encontradas e vivenciadas na abordagem familiar de potencial doador de órgãos, são caracterizadas por conflitos e situações que expõem o profissional a uma atmosfera de sentimentos de acolhimento e de empatia.

Purpose The purpose of this study was to report trends in the prevalence of early graft failure after endothelial keratoplasty in the United States. Methods Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) graft volumes were collected from records maintained by 6 major eye banks in the United States from January 1, 2013, to December 31, 2018. The prevalence and presumed cause of early graft failures (defined as a graft with persistent edema or regrafted within 8 weeks after keratoplasty) each year were sourced from surgeon-reported adverse events. Failed graft cases from the 3 eye banks were compared with nonfailures at the donor and recipient levels to perform subset analysis of factors associated with early graft failure. Results A total of 51,887 endothelial keratoplasty tissues were distributed during the study period; 72% were DSAEK grafts. The total number of early graft failures reported was 168 of 14,284 (1.18%) for DMEK and 322 of 37,603 (0.86%) for DSAEK. Early DMEK failures decreased from 2013 (7.69%) to 2018 (0.68%). In generalized linear mixed model analyses adjusting for donor tissue characteristics, recipient age, and diagnosis, an association of borderline significance was found between higher donor age and early failure [odds ratio (95% confidence interval): 1.03 (1.00-1.05); unit change of 1 yr] and DSAEK [odds ratio 1.02 (1.00-1.04); unit of change 1 yr] cases. Conclusions The proportion of early graft failures in DMEK decreased over time and was comparable with failure rates in DSAEK at the end of the study period. The surgical learning curve might have played a role.

The aim of this study was to explore how the implementation of the quality management system (QM; according to DIN EN ISO 9001 : 2008) at the LIONS Eye Bank impacted the rate and reasons for discarding donated corneas. The QM system was introduced in November 2010.The rate of and reasons for discarding cornea tissues at the LIONS Eye Bank Saar-Lor-Lux,Trier/Western Palatinate from 2006 to 2016 were analysed retrospectively. 4,140 corneas from 2,084 donors were analysed. 1,640 corneas were processed before the QM system had been introduced and 2,500 corneas thereafter. Main reasons for discarding cornea tissues were endothelial quality, contamination of the medium and a positive conjunctival swab. The data was extracted from clinical files and data filing systems, entered into a Microsoft Access database and analysed statistically with SPSS.Following the implementation of a QM system, the discard rate decreased significantly from 50.1% to 39.7% (p 0.0001). Prior to the implementation of the QM system, 493 (30.1%) cornea tissues had been discarded due to endothelial quality, while this figure improved significantly to 604 (24.2%) after the QM system had been implemented (p 0.0001). Contamination was the reason for discarding tissue in 173 (10.5%) cases before implementation of the QM system, and in 124 (5.0%) cases thereafter (p 0.0001). Positive conjunctival swab was the reason for discarding tissue in 10 (0.6%) cases before the QM system had been implemented, and in 53 (2.1%) cases thereafter (p 0.0001).Implementation of a QM system significantly reduced the rate of discarded donor tissue in the LIONS Eye Bank. Better management of contamination as a reason for discarding cornea tissues can be attributed to improved standards, protocols and training that are part of this QM system.Ziel dieser Studie war es, den Einfluss der Einführung des QM-Systems (QM: Qualitätsmanagement, nach DIN EN ISO 9001 : 2008) auf die Verwerfungsrate und -gründe von Spendergewebe in einer Hornhautbank zu erforschen. Die Einführung des QM-Systems erfolgte im November 2010.Die Verwerfungsrate und -gründe wurden retrospektiv für die Jahre 2006 bis 2016 in der LIONS-Hornhautbank Saar-Lor-Lux, Trier/Westpfalz des Universitätsklinikums des Saarlandes (UKS) analysiert. 4140 Hornhäute von 2084 Spendern wurden einbezogen. 1640 Hornhäute entstammten der Zeit vor Einführung des zertifizierten QM-Systems (nach DIN EN ISO 9001 : 2008) und 2500 Hornhäute nach Einführung. Bei den analysierten Verwerfungsgründen handelte es sich um die Endothelqualität, Kontamination des Mediums und der positiven Bindehautabstriche. Die Daten der Spender und Hornhäute wurden aus klinikinternen Dokumenten und Systemen in eine Microsoft-Access-Datenbank übertragen und mittels SPSS statistisch ausgewertet.Nach Einführung des QM-Systems sank die Verwerfungsrate von 50,1 auf 39,7% (p 0,0001). Vor der Einführung wurden 493 (30,1%) der Hornhäute aufgrund der Endothelqualität verworfen, nach der Einführung waren es 604 (24,2%) (p 0,0001). Aufgrund einer Kontamination wurden vor Einführung 173 (10,5%) Hornhäute und nach Einführung 124 (5,0%) verworfen (p 0,0001). Wegen des Bindehautabstriches wurden vor Einführung 10 (0,6%) und nach Einführung 53 (2,1%) verworfen (p 0,0001).Die Verwerfungsrate in der LIONS-Hornhautbank konnte nach Einführung des QM-Systems signifikant gesenkt werden. Durch vermehrte Mitarbeiterschulungen sowie durch einheitliche und höhere Standards des QM-Systems bez. Ablauf der Entnahme und Kultivierung konnte die Kontaminationsrate signifikant reduziert werden.

PurposePre-Descemet’s endothelial keratoplasty (PDEK) donor tissue preparation involves the intrastromal injection of air to create a type 1 big bubble (BB) and avoidance of the creation of a type 2 BB. The purpose of this study was to design and test a technique to consistently creates a type 1 BB without risk of creating a type 2 BB.MethodsA prospective matched study with 64 human donor sclerocorneal discs, which were not suitable for corneal transplantation, was conducted. The corneas were divided into two groups, of which 32 were subjected to the standard technique of preparing the PDEK donor tissue (group 1, control) and 32 new technique, where in the donor Descemet’s membrane was scored with a Sinskey hook. Frequency of occurrence of different types of BB was compared and statistically analysed.ResultsWith the standard technique (group 1), type 1 BB occurred in 53.1%, type 2 BB in 34.4% and mixed BB in 12.5% of samples. With the scoring technique (group 2), a type 1 BB occurred in 100% of the samples. No type 2 or mixed BB occurred in any case in group 2. The difference in creation of a type 1BB between the two groups was statistically significant (p=0.00).ConclusionThe scoring technique is a simple, inexpensive and reproducible option to consistently achieve a type 1 BB to prepare PDEK graft tissue. The next step would be to study the clinical outcomes of PDEK performed with tissue obtained by the scoring technique.

The use of bulk nanobubbles in biomedicine is increasing in recent years, which is attributable to the array of therapeutic and diagnostic tools promised by developing bulk nanobubble technologies. From cancer drug delivery and ultrasound contrast enhancement to malaria detection and the diagnosis of acute donor tissue rejection, the potential applications of bulk nanobubbles are broad and diverse. Developing these technologies to the point of clinical use may significantly impact the quality of patient care. This review compiles and summarizes a representative collection of the current applications, fabrication techniques, and characterization methods of bulk nanobubbles in biomedicine. Current state-of-the-art generation methods are not designed to create nanobubbles of high concentration and low polydispersity, both characteristics of which are important for several bulk nanobubble applications. To date, microfluidics has not been widely considered as a tool for generating nanobubbles, even though the small-scale precision and real-time control offered by microfluidics may overcome the challenges mentioned above. We suggest possible uses of microfluidics for improving the quality of bulk nanobubble populations and propose ways of leveraging existing microfluidic technologies, such as organ-on-a-chip platforms, to expand the experimental toolbox of researchers working to develop biomedical nanobubbles.

Purpose To investigate stamp visibility and endothelial cell loss (ECL) after the application of an orientation mark to Descemet membrane endothelial keratoplasty (DMEK) grafts supported by an air bubble. Methods Eighteen DMEK grafts were prepared at an eye bank using a technique where an orientation mark was applied to the stromal surface of a DMEK graft that was supported by a small air bubble placed at the edge of the 2 endothelial surfaces of the graft. Grafts were evaluated at 2 and 5 days for stamp visibility and at 5 days with calcein-AM staining for ECL. Nine grafts underwent cross-country shipping, and the ECL of shipped and nonshipped grafts was compared using unpaired t test. Results All 18 DMEK grafts exhibited a single, solid, readily visible orientation mark 2 and 5 days after preparation with a mean ECL of 13.5% ± 4.9%. Shipping conditions had no effect on stain retention or ECL. Conclusions The application of an orientation stamp to a DMEK graft over an air bubble in an eye bank setting results in a single, solid orientation mark that is readily visible within the period in which most eye bank-prepared tissue is used. This technique produces no further ECL compared with the methods where the orientation stamp is applied through a stromal window. Eye bank technicians and surgeons can be confident that this modified preparation technique results in transplant-quality DMEK grafts with the additional benefit of conserving the stromal cap for use in other anterior lamellar procedures, thereby making efficient use of donor tissue.

Endothelial keratoplasty has revolutionized the treatment of corneal endothelial dysfunction and lowered the threshold for treatment by providing rapid visual rehabilitation and setting a high standard for safety and efficacy. Over time, endothelial keratoplasty techniques have evolved toward the use of thinner tissue to optimize visual outcomes; refinements have facilitated donor tissue preparation, handling, and attachment; and adaptations have expanded utilization in eyes with challenging ocular anatomy. Despite early concerns about graft longevity, emerging 10-year endothelial cell loss and graft survival data have been encouraging. A shortage of human donor corneas restricts utilization in many areas of the world and is driving a search for keratoplasty alternatives. Further work is needed to expand the donor supply, minimize impediments to adoption, optimize graft survival, and improve refractive predictability.

Pure autologous breast reconstruction in thin patients creates challenges. This review highlights techniques to optimize the scarce donor tissue available, approaches to reconstruction, and microsurgical techniques. A systematic approach to maximize breast volume and the skin envelope in patients who underwent pure autologous breast reconstruction by a single senior surgeon is presented with a clinical case series. Included in the study were 125 patients (217) with autologous breast reconstructions. Although DIEP flaps were the commonest flap used overall (79%), within in the low body mass index ( 50%).

Endothelial keratoplasty (EK) is increasingly used to treat corneal endothelial disease. However, issues remain with EK including a non-zero rejection rate, shortage of donor tissue, and technical challenges for Descemet’s membrane endothelial keratoplasty. Technologies that might solve these issues include small-molecule drugs, surgical innovations, cell therapy, tissue engineering, and gene therapy. Our purpose is to inform ophthalmologists, eye bankers, and eye health professionals of technologies that could impact practice in the near future. Recent advances are targeted at solving known issues with EK. Although none is yet routine, some are in clinical trials. Technologies that are closest to an ideal solution are those facing the highest regulatory and commercial hurdles. In the future, there will multiple options for the treatment of corneal endothelial cell failure. Which of these differing treatments will be used will depend on their efficacy as well as commercial, regulatory, and patient factors.

Purpose To describe a simple finding that can be used to determine donor tissue orientation in Descemet membrane endothelial keratoplasty (DMEK). This involves the appearance of a highly reflective round curved line from an overlapping graft edge within the anterior chamber using light from an endoilluminator. We here name this Kobayashi sign (K-sign). Methods Twelve consecutive eyes from 12 patients who underwent DMEK were evaluated for the presence of a K-sign. The presence of Berrospi sign (B-sign), a double-line reflection from the peripheral curls of the Descemet membrane (DM) roll that has been reported to be useful for correct graft orientation, was also evaluated. Results Of 12 cases, 3 donors showed a loosely scrolled roll soon after DM donor insertion; all 3 of these showed a positive B-sign only when the endoilluminator was used. Nine donors showed a tightly scrolled DM roll without a B-sign; among these 9 donors, a K-sign was visible in 7 cases only when the endoilluminator was used. The remaining 2 cases with a tight scroll configuration showed no K-sign even with the use of endoillumination, indicating that the roll edge was located completely downward; rotation of the roll using a small jet of fluid from paracentesis revealed K-sign in these cases. Conclusions This technique is useful for determining the correct orientation of a tightly scrolled DM roll, subsequently enabling rapid DMEK surgery. For loosely scrolled DM roll, endoillumination enhanced B-sing is proven useful.

Purpose To describe the risk factors, management, and outcome of delayed Descemet membrane (DM) detachment after penetrating keratoplasty (PK) for keratoconus. Methods We report 7 eyes from 6 cases and combine these data with 7 previous case reports identified by a search of PubMed. Results DM detachment occurred at a median of 25 years (range, 7-33 years) after PK. One individual had bilateral detachments. There was typically a mild ocular discomfort accompanied in some cases by a rapid onset of visual blur. Cases were often treated for allograft rejection before a DM detachment was suspected and confirmed by optical coherence tomography. Detachments were limited to the donor tissue in 11 eyes, but a DM break was identified at the time of onset in only 4 eyes. Thinning of the host corneal rim with ectasia was reported in 8 eyes (57%). In 3 eyes, the detachment resolved spontaneously, but in 2 eyes, a detachment was still present at 12 months. Gas tamponade to reattach the DM was performed in 9 eyes and was effective in 4 eyes. Five eyes underwent a repeat PK or endothelial keratoplasty. Histology showed fibroblastic proliferation on the stromal surface of the folded DM. Conclusions The cause for DM detachment many years after PK is unknown, although progressive thinning of the host cornea and secondary graft ectasia may be implicated. Gas tamponade can be effective, but a repeat keratoplasty might be necessary. DM detachment should be included in the differential diagnosis for late-onset corneal edema after PK.

To investigate the appropriate surgical stage for Descemet membrane (DM) removal during donor preparation in deep anterior lamellar keratoplasty (DALK). This study included 83 corneoscleral buttons that were used for DALK. The donor DM was removed randomly either before (group 1; 43 eyes) or after (group 2; 40 eyes) trephination. The time required for DM removal was recorded, and the geometric properties of cut buttons were evaluated after trephination. The intraoperative video recordings were reviewed to determine if the dissections were performed at the stroma-DM plane as it was intended. The time needed to remove the DM, the rate of correct dissection at the intended stroma-DM plane, and the roundness and precision of the donor cuts were compared between the groups. The two groups were comparable in donor characteristics, including age, quality of the tissue, and trephination size. Time spent to remove DM was significantly shorter in group 1 (68.9 ± 48.2 s) than group 2 (117.7 ± 52.7 s, P = 0.001). DM stripping was performed incorrectly in 2 corneas (4.7%) in group 1 and in 12 corneas (30%) in group 2 (P = 0.01). No difference was found between the groups in the roundness and precision of donor button cuts. DM removal before trephination did not detrimentally affect the geometric properties of punched donor tissues. When DM stripping was performed before trephination, the donor tissue was less traumatized and posterior graft surface was more likely to be regular; therefore, it is advisable to remove DM before trephination during donor preparation for DALK.

Adipose-derived stem cells (ASCs) are being increasingly exploited for regenerative medicine applications owing to their many unique features, such as abundant donor tissue, easy isolation, immunomodulatory capacities, and migratory, proliferation, and lineage differentiation functions. Results from a large number of clinical trial studies suggest their significant potential in treating a wide range of diseases. However, the functions of ASCs decline with aging, negatively impacting their clinical application. To overcome this obstacle, rejuvenation of aging stem cells is a fast-developing research field. The development of strategies to rejuvenate stem cells is critically dependent on the knowledge of stem cell aging mechanisms. As such, extensive studies have been devoted to generating a global understanding of stem cell aging and the specific cellular mechanisms responsible for regulating the aging process.

In recent decades, cell biology has made rapid progress. Cell isolation and cultivation techniques, supported by modern laboratory procedures and experimental capabilities, provide a wide range of opportunities for in vitro research to study physiological and pathophysiological processes in health and disease. They can also be used very efficiently for the analysis of biomaterials. Before a new biomaterial is ready for implantation into tissues and widespread use in clinical practice, it must be extensively tested. Experimental cell models, which are a suitable testing ground and the first line of empirical exploration of new biomaterials, must contain suitable cells that form the basis of biomaterial testing. To isolate a stable and suitable cell culture, many steps are required. The first and one of the most important steps is the collection of donor tissue, usually during a surgical procedure. Thus, the collection is the foundation for the success of cell isolation. This article explains the sources and neurosurgical procedures for obtaining brain tissue samples for cell isolation techniques, which are essential for biomaterial testing procedures.

This article highlights the need for skin donations to treat burn wounds. South Africa has an exceptionally high number of burn wound victims per annum. The ideal way to treat burn wounds is to transplant skin from another part of the patient’s body to the affected areas (autografts). Unfortunately, this is not always possible or feasible and in those cases skin from cadavers (allografts) should be used, but this can only be done if the deceased has indicated a wish during his or her lifetime that tissue be donated for transplantation use after death. If the deceased has not indicated his or her wish to be a tissue donor, family members could be asked to consent to a donation. The article looks at the legal requirements in South Africa for a valid skin donation as well as the requirements should skin be imported owing to a lack of enough tissue donors in the country. This position is contrasted to the position in the United Kingdom with a view to establishing whether South Africa can learn from another jurisdiction concerning the procurement of skin for transplantation. The possible reasons that people do not donate skin are also touched upon.

Purpose of Review: The ocular surface is a potential site of ocular involvement by SARS-CoV-2 infection. We performed a review of the literature to understand the pathogenesis of SARS-CoV-2 disease manifestations on the ocular surface as well as to elucidate emerging treatment patterns and practice changes during the COVID-19 pandemic. Recent Findings: The ocular manifestations of SARS-CoV-2 are likely limited to a mild and transient conjunctivitis. Other manifestations have not been validated in larger cohorts. Ocular surface tissue should be considered potentially infectious due to the presence of host receptors on surface tissues. The availability of donor tissue in lower-middle income countries has been greatly impacted by the pandemic and would benefit from further investigation into transmissibility through donor tissue. Summary: Transmission of SARS-CoV-2 through the ocular surface has yet to be confirmed. The most common ocular manifestation is a mild conjunctivitis. Ocular surface surgeons face specific challenges in the use of donor tissues and aerosolizing procedures and have adapted practice patterns accordingly.

Introduction. The purpose of this case report was to show the clinical long-term stability of a successful two-step root coverage procedure. A combination of two single techniques was used to treat an isolated deep-wide defect. Case Presentation. A 28-year-old female patient was referred in order to treat a single recession defect at #22. Due to her fear of dental procedures and a poor economic situation, the team developed an alternative solution. They used a modified apically repositioned flap (MARF) to increase the donor area and then a laterally positioned flap (LPF) to treat the root defect. Clinical evaluation at the three-year follow-up revealed complete resolution of the defect, a gain in clinical attachment, excellent esthetic results, and minor morbidity to the patient. Conclusion. The combination of the MARF and the LPF procedures was able to successfully treat a single deep recession defect with some advantages over traditional techniques such as simplicity, ideal color match of tissues, and the absence of palatal donor tissue.

We report a new technique to replace a manufactured poly(methyl methacrylate) (PMMA) ring with a biologic stromal ring fashioned from human corneal donor tissue in eyes with stromal melting above the PMMA ring. The biologic stromal ring is prepared using manual or femtosecond laser trephination of a donor cornea to obtain a 360-degree ring that is denuded and adjusted to match the PMMA ring being replaced. The biologic ring is attached to the PMMA ring. The PMMA ring is pushed and retrieved from the other side, which installs the biologic ring in place. Six biologic stromal rings were implanted successfully in 5 eyes of 5 patients with previous stromal melting; no complications were reported up to 6 months postoperatively. The biologic stromal ring stopped and healed the melting, prevented further ring complications, and preserved the therapeutic refractive effect of the previously implanted PMMA ring.

Best practices in fat transfer to the face focus on tissue harvest and processing techniques. This article discusses the role of adipose-derived mesenchymal stem cells (MSCs) in mitigating tissue loss in grafting. Discrepancies among common practice and recent study results have propagated uncertainty with long-term results. Fortunately, recent increases in the understanding of these MSCs are leading providers to identify statistically more favorable tissue donor sites, harvest technique, and preparation methods to increase their concentration in transferred tissue. Future studies are needed to support or confound the long-term effects of MSC transfer on facial fat grafting.

The Peters’s Anomaly (PA) is an infrequent congenital anomaly of a cornea and anterior segment of eye. The rarity of this pathology and difficulty bound to inspection of newborns generate a situation when more or less certain clinical approaches to maintaining this anomaly remain obscure for most of children’s ophthalmologists. Purpose. To study clinical implications and to estimate results of surgical treatment in children with PA. Material and methods. Under observation from 1996 for 2016 on examination and treatment there were 51 children with the PA different forms, aged from 3 months up to 10 years: 1 group – mesodermal – 20 people (37%), 2 – group the ectodermal 31 child (63%). Surgical treatment – penetrating keratoplasty (PKP) was carried out at 43 patients (69 eyes) aged from 8 up to 36 months. At other children (8 people) surgery was contraindicative because of serious somatic and eye pathology. Clinical-functional and ophthalmologic examination at all was conducted in the conditions of medication sleep. PKP carried out by a traditional technique, as donor material used a fresh cadaver cornea with prescription of a fence from death moment before operation no more than 48 hours. The biological result of surgery was estimated by a moment method (or Kaplana-Maier’s method) by means of which calculated so-called survival of a graft. Functional result – at children to 3-x years estimated approximately: on tracking of the child toys from a certain distance and method of a preferable look, at children of advanced age according to Sivtsev-Golovin’s table. Postoperative observation proceeded from 3 months to 15 years. The corneal disks removed during surgery were exposed to a histological research. Results. Within the first year after PKP a transparence of the replaced cornea remained in 1 group on 29 eyes (90%), in 2 group – at 21 patients of 26 eyes (67%). In 2 years after surgery the transparent donor cornea at children in 1 group remained at 17 patients (20 eyes, 62%); in – the second at 15 patients of 18 eyes (54%). In 5 years after surgery – at patients of 1 group a transparence of the replaced donor tissue was kept by 17 eyes (53%), in the second only 12 of 31 executed surgery (39%). In 10 years transparent were 53% and 31% of corneas, respectively. In 15 years after surgery a transparence was kept in 1 group of 15 eyes (46%), in 2 – on 9 (22%). Visual acuity (0,3 and above) was observed at 8 of 13 children (61%) after surgery about one year at children of advanced age only in 27% of cases, even at tr ansparent engraftment of a graft. Conclusion. The keratoplasty at PA at children of early age is the only chance to save the child from a blindness and disability on vision.