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Background: Pediatric recipients of living donor kidneys have a low rate of delayed graft function (DGF). We examined the incidence, risk factors and outcomes of DGF in pediatric patients who received a living donor allograft., Methods: The STARfile was queried to examine all pediatric patients transplanted with a living donor kidney between 2000 and 2020. Donor and recipient demographic data were examined, as were survival and outcomes. Recipients were stratified into DGF and no DGF groups. DGF was defined as the need for dialysis within the first week after transplant., Results: 6480 pediatric patients received a living donor (LD) kidney transplant during the study period. 269 (4.2%) developed DGF post-transplant. Donors were similar in age, creatinine, and cold ischemia time. Recipients of kidneys with DGF were similar in age, sensitization status and HLA mismatch. Focal segmental glomerulosclerosis (FSGS) was the most common diagnosis in recipients with DGF, and allograft thrombosis was the most common cause of graft loss in this group. Small recipients (weight < 15 kg) were found to have a significantly higher rate of DGF. Length of stay doubled in recipients with DGF, and rejection rates were higher post-transplant. Recipients of LD kidneys who developed DGF had significantly worse 1 year allograft survival (67% vs. 98%, p < .0001)., Conclusions: Pediatric living donor kidney transplant recipients who experience DGF have significantly poorer allograft survival. Optimizing the donor and recipient matching to avoid compounding risks may allow for better outcomes., (© 2022 Wiley Periodicals LLC.)

Objective: During the initial wave of the COVID-19 pandemic, organ transplantation was classified a CMS Tier 3b procedure which should not be postponed. The differential impact of the pandemic on access to liver transplantation was assessed., Summary Background Data: Disparities in organ access and transplant outcomes among vulnerable populations have served as obstacles in liver transplantation., Methods: Using UNOS STARfile data, adult waitlisted candidates were identified from March 1, 2020 to November 30, 2020 (n = 21,702 pandemic) and March 1, 2019 to November 30, 2019 (n = 22,797 pre-pandemic), and further categorized and analyzed by time periods: March to May (Period 1), June to August (Period 2), and September to November (Period 3). Comparisons between pandemic and pre-pandemic groups included: Minority status, demographics, diagnosis, MELD, insurance type, and transplant center characteristics. Liver transplant centers (n = 113) were divided into tertiles by volume (small, medium, large) for further analyses. Multivariable logistic regression was fitted to assess odds of transplant. Competing risk regression was used to predict probability of removal from the waitlist due to transplantation or death and sickness. Additional temporal analyses were performed to assess changes in outcomes over the course of the pandemic., Results: During Period 1 of the pandemic, Minorities showed greater reduction in both listing (-14% vs -12% Whites), and transplant (-15% vs -7% Whites), despite a higher median MELD at transplant (23 vs 20 Whites, P < 0.001). Of candidates with public insurance, Minorities demonstrated an 18.5% decrease in transplants during Period 1 (vs -8% Whites). Although large programs increased transplants during Period 1, accounting for 61.5% of liver transplants versus 53.4% pre-pandemic (P < 0.001), Minorities constituted significantly fewer transplants at these programs during this time period (27.7% pandemic vs 31.7% pre-pandemic, P = 0.04). Although improvements in disparities in candidate listings, removals, and transplants were observed during Periods 2 and 3, the adjusted odds ratio of transplant for Minorities was 0.89 (95% CI 0.83-0.96, P = 0.001) over the entire pandemic period., Conclusions: COVID-19's effect on access to liver transplantation has been ubiquitous. However, Minorities, especially those with public insurance, have been disproportionately affected. Importantly, despite the uncertainty and challenges, our systems have remarkable resiliency, as demonstrated by the temporal improvements observed during Periods 2 and 3. As the pandemic persists, and the aftermath ensues, health care systems must consciously strive to identify and equitably serve vulnerable populations., Competing Interests: Conflict of interest: Raymond Lynch receives research support from the Mid-America Transplant Foundation. The authors report no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Fungal infections cause significant mortality and morbidity worldwide, and the limited existing antifungal reservoir is further weakened by the emergence of strains resistant to echinocandins, a first line of antifungal therapy. Candida glabrata is an opportunistic fungal pathogen that rapidly develops mutations in the echinocandin drug target β-1,3-glucan synthase (GS), which are associated with drug resistance and clinical failure. Although echinocandins are considered fungicidal in Candida sp., a subset of C. glabrata cells survive echinocandin exposure, forming a drug-tolerant cell reservoir, from which resistant mutations are thought to emerge. Despite their importance, the physiology of rare drug-tolerant cells is poorly understood. We used fluorescence-activated cell sorting to enrich for echinocandin-tolerant cells, followed by modified single-cell RNA sequencing to examine their transcriptional landscape. This analysis identified a transcriptional signature distinct from the stereotypical yeast environmental stress response and characterized by upregulation of pathways involved in chromosome structure and DNA topology and downregulation of oxidative stress responses, of which the latter was observed despite increased levels of reactive oxygen species. Further analyses implicated mitochondria in echinocandin tolerance, wherein inhibitors of mitochondrial complexes I and IV reduced echinocandin-mediated cell killing, but mutants lacking various mitochondrial components all showed an echinocandin hypotolerant phenotype. Finally, GS enzyme complexes purified from mitochondrial mutants exhibited normal in vitro inhibition kinetics, indicating that mitochondrial defects influence cell survival downstream of the drug-target interaction. Together, these results provide new insights into the C. glabrata response to echinocandins and reveal a multifactorial role of mitochondria in echinocandin tolerance. IMPORTANCE Echinocandin drugs are a first-line therapy to treat invasive candidiasis, which is a major source of morbidity and mortality worldwide. The opportunistic fungal pathogen Candida glabrata is a prominent bloodstream fungal pathogen, and it is notable for rapidly developing echinocandin-resistant strains associated with clinical failure. Echinocandin resistance is thought to emerge within a small echinocandin-tolerant subset of C. glabrata cells that are not killed by drug exposure, but mechanisms underlying echinocandin tolerance are still unknown. Here, we describe the unique transcriptional signature of echinocandin-tolerant cells and the results of follow-up analyses, which reveal a multifactorial role of mitochondria in C. glabrata echinocandin tolerance. In particular, although chemical inhibition of respiratory chain enzymes increased echinocandin tolerance, deletion of multiple mitochondrial components made C. glabrata cells hypotolerant to echinocandins. Together, these results provide new insights into the C. glabrata response to echinocandins and reveal the involvement of mitochondria in echinocandin tolerance.

DNA damage checkpoints are key guardians of genome integrity. Eukaryotic cells respond to DNA damage by triggering extensive phosphorylation of Rad53/CHK2 effector kinase, whereupon activated Rad53/CHK2 mediates further aspects of checkpoint activation, including cell cycle arrest and transcriptional changes. Budding yeast Candida glabrata , closely related to model eukaryote Saccharomyces cerevisiae , is an opportunistic pathogen characterized by high genetic diversity and rapid emergence of drug-resistant mutants. However, the mechanisms underlying this genetic variability are unclear. We used Western blotting and mass spectrometry to show that, unlike S. cerevisiae , C. glabrata cells exposed to DNA damage did not induce C. glabrata Rad53 (CgRad53) phosphorylation. Furthermore, flow cytometry analysis showed that, unlike S. cerevisiae , C. glabrata cells did not accumulate in S phase upon DNA damage. Consistent with these observations, time-lapse microscopy showed C. glabrata cells continuing to divide in the presence of DNA damage, resulting in mitotic errors and cell death. Finally, transcriptome sequencing (RNAseq) analysis revealed transcriptional rewiring of the DNA damage response in C. glabrata and identified several key protectors of genome stability upregulated by DNA damage in S. cerevisiae but downregulated in C. glabrata , including proliferating cell nuclear antigen (PCNA). Together, our results reveal a noncanonical fungal DNA damage response in C. glabrata , which may contribute to rapidly generating genetic change and drug resistance. IMPORTANCE In order to preserve genome integrity, all cells must mount appropriate responses to DNA damage, including slowing down or arresting the cell cycle to give the cells time to repair the damage and changing gene expression, for example to induce genes involved in DNA repair. The Rad53 protein kinase is a conserved central mediator of these responses in eukaryotic cells, and its extensive phosphorylation upon DNA damage is necessary for its activation and subsequent activity. Interestingly, here we show that in the opportunistic fungal pathogen Candida glabrata , Rad53 phosphorylation is not induced by DNA damage, nor do these cells arrest in S phase under these conditions, in contrast to the closely related yeast Saccharomyces cerevisiae Instead, C. glabrata cells continue to divide in the presence of DNA damage, resulting in significant cell lethality. Finally, we show that a number of genes involved in DNA repair are strongly induced by DNA damage in S. cerevisiae but repressed in C. glabrata Together, these findings shed new light on mechanisms regulating genome stability in fungal pathogens., (Copyright © 2020 Shor et al.)

Hereditary diffuse gastric cancer (HDGC) is an autosomal dominant cancer syndrome that is characterised by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is largely caused by inactivating germline mutations in the tumour suppressor gene CDH1, although pathogenic variants in CTNNA1 occur in a minority of families with HDGC. In this Policy Review, we present updated clinical practice guidelines for HDGC from the International Gastric Cancer Linkage Consortium (IGCLC), which recognise the emerging evidence of variability in gastric cancer risk between families with HDGC, the growing capability of endoscopic and histological surveillance in HDGC, and increased experience of managing long-term sequelae of total gastrectomy in young patients. To redress the balance between the accessibility, cost, and acceptance of genetic testing and the increased identification of pathogenic variant carriers, the HDGC genetic testing criteria have been relaxed, mainly through less restrictive age limits. Prophylactic total gastrectomy remains the recommended option for gastric cancer risk management in pathogenic CDH1 variant carriers. However, there is increasing confidence from the IGCLC that endoscopic surveillance in expert centres can be safely offered to patients who wish to postpone surgery, or to those whose risk of developing gastric cancer is not well defined., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: This single-center, retrospective analysis investigated the clinical outcomes of a novel vascular closure device (VASCADE, Cardiva Medical, Santa Clara, CA) for closure of 7F femoral venotomies., Background: The VASCADE closure device has been widely used to close arteriotomy sites following femoral procedures; however, little data have been published regarding the device's utility in closure of venotomy sites after procedures such as right-heart catheterization., Methods: This was a retrospective analysis of outcomes in 102 consecutive patients who underwent venous closure using the VASCADE device following diagnostic right and left-heart catheterization between April 2016 to May 2018. Patients' age, gender, valvular disease status, comorbidities, and periprocedural use of antiplatelet/anticoagulant therapy were analyzed., Results: Closure was successful in 99% (101/102) of patients with respect to achieving the primary outcome of rapid hemostasis in ≤3 min. There was one device failure requiring manual compression, with no further complications. There were no other related adverse events or complications through 30 days of follow-up., Conclusions: The VASCADE device achieved venous hemostasis in nearly all our patients. We believe devices for venous closure can aid in improving patient experience, safety, and efficiency during these procedures., (© 2018 Wiley Periodicals, Inc.)

Background: Portal vein thrombosis (PVT) is relatively common among candidates for liver transplantation and can present significant intraoperative challenges. Depending on the extent of PVT, thromboendovenectomy (TEV), portal bypass, or systemic inflow may be required to restore portal inflow. While TEV is the most commonly used approach to restore anatomic portal inflow, portal vein injury and life-threatening hemorrhage are risks with this technique., Case Report: We present a salvage technique for managing portal vein injury during TEV using intraluminal balloon occlusion of the portal vein during portal vein repair and reconstruction. This alternative mode of bleeding control optimizes exposure to the retropancreatic space and avoids direct application of vascular clamps that can cause further injury to the vessel and surrounding tissue., Conclusion: Careful preoperative planning and anticipation of potential problems are essential for safe and effective management of complex PVT intraoperatively. The balloon-occlusion technique can facilitate safe and efficient repair of a portal vein injury during TEV for liver transplantation.

Germline CDH1 mutations confer a high lifetime risk of developing diffuse gastric (DGC) and lobular breast cancer (LBC). A multidisciplinary workshop was organised to discuss genetic testing, surgery, surveillance strategies, pathology reporting and the patient's perspective on multiple aspects, including diet post gastrectomy. The updated guidelines include revised CDH1 testing criteria (taking into account first-degree and second-degree relatives): (1) families with two or more patients with gastric cancer at any age, one confirmed DGC; (2) individuals with DGC before the age of 40 and (3) families with diagnoses of both DGC and LBC (one diagnosis before the age of 50). Additionally, CDH1 testing could be considered in patients with bilateral or familial LBC before the age of 50, patients with DGC and cleft lip/palate, and those with precursor lesions for signet ring cell carcinoma. Given the high mortality associated with invasive disease, prophylactic total gastrectomy at a centre of expertise is advised for individuals with pathogenic CDH1 mutations. Breast cancer surveillance with annual breast MRI starting at age 30 for women with a CDH1 mutation is recommended. Standardised endoscopic surveillance in experienced centres is recommended for those opting not to have gastrectomy at the current time, those with CDH1 variants of uncertain significance and those that fulfil hereditary DGC criteria without germline CDH1 mutations. Expert histopathological confirmation of (early) signet ring cell carcinoma is recommended. The impact of gastrectomy and mastectomy should not be underestimated; these can have severe consequences on a psychological, physiological and metabolic level. Nutritional problems should be carefully monitored., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)