A global association between Covid-19 cases and airborne particulate matter at regional level.

Evidences of an association between air pollution and Covid-19 infections are mixed and inconclusive. We conducted an ecological analysis at regional scale of long-term exposure to air-borne particle matter and spread of Covid-19 cases during the first wave of epidemics. Global air pollution and climate data were calculated from satellite earth observation data assimilated into numerical models at 10 km resolution. Main outcome was defined as the cumulative number of cases of Covid-19 in the 14 days following the date when > 10 cumulative cases were reported. Negative binomial mixed effect models were applied to estimate the associations between the outcome and long-term exposure to air pollution at the regional level (PM10, PM2.5), after adjusting for relevant regional and country level covariates and spatial correlation. In total we collected 237,749 Covid-19 cases from 730 regions, 63 countries and 5 continents at May 30, 2020. A 10 µg/m3 increase of pollution level was associated with 8.1% (95% CI 5.4%, 10.5%) and 11.5% (95% CI 7.8%, 14.9%) increases in the number of cases in a 14 days window, for PM2.5 and PM10 respectively. We found an association between Covid-19 cases and air pollution suggestive of a possible causal link among particulate matter levels and incidence of COVID-19.

Everolimus vs Mycophenolate Mofetil in Combination With Tacrolimus: A Propensity Score-matched Analysis in Liver Transplantation.

BACKGROUND: No trial has investigated the long-term outcome of everolimus (EVR)-incorporating immunosuppression vs tacrolimus (TAC) and mycophenolate mofetil (MMF) after liver transplantation. MATERIALS AND METHODS: With a propensity score methodology, 178 recipients on TAC and MMF were compared to 178 patients on TAC and EVR. RESULTS: At a median (interquartile range) follow-up of 45 (46.3) months, the probability of treated biopsy-proven acute rejection, graft loss, and death was 36.6% for MMF and 28.1% for EVR (P = .0891). Treated biopsy-proven acute rejection was numerically lower for EVR (3.3% vs 7.3%, P = .09), while adverse events (70.2% vs 58.9%, P = .02) and drug discontinuations (21.3% vs 11.8%, P = .01) were significantly higher with regard to hypercholesterolemia (P = .001), thrombocytopenia (P = .0062), and edema (P = .0107). Patients on MMF showed more hypertension (P = .0315), tremor (P = .0006), cytomegalovirus infection (P = .0165), and malignancies (P = .0175). EVR was associated with lesser deterioration in mean (SD) renal function at the latest follow-up (-2.2 (1.8) vs -5.1 (3.2) mL/min/1.73 m2, t = 3.6, P = .005). CONCLUSIONS: The efficacy of the combination of TAC and EVR is comparable to that of TAC and MMF. Drug discontinuations and adverse events were higher for patients on EVR, but these latter showed less hypertension, cytomegalovirus infection, and renal dysfunction. The observed reduction in posttransplant malignancies for EVR requires longer follow-up to be confirmed.

Salvage of an Octogenarian Liver Graft Using Normothermic Perfusion: A Case Report.

Liver transplantation with very old donors is safe, but is associated with an increased incidence of ischemic-type biliary lesions and delayed graft function. Normothermic machine perfusion (NMP) is a novel technique for preservation of liver grafts and has the potential to reduce ischemia-reperfusion injury. A case is reported here of a liver transplantation (LT) with a graft from an 83-year-old brain-dead donor. Procurement was with dual perfusion and en bloc, modified fast technique. Donor kidneys were not transplanted due to severe atherosclerosis and poor perfusion. The liver was shipped to the transplantation center and underwent NMP with a blood-based perfusate. During machine perfusion lactates decreased, vascular flow was stable, and bile production restored, and the graft was considered suitable for transplantation. The postoperative course was uneventful and 4 months after surgery the patient is in good clinical condition with normal liver function. To date, few LTs have been performed with NMP in humans, but its preliminary results are promising. NMP allows functional evaluation of the graft and possibly reduction of post-transplantation complications when extended-criteria donor grafts are used.

Use of octogenarian donors for liver transplantation: a survival analysis.

Use of very old donors in liver transplantation (LT) is controversial because advanced donor age is associated with a higher risk for graft dysfunction and worse long-term results, especially for hepatitis C virus (HCV)-positive recipients. This was a retrospective, single-center review of primary, ABO-compatible LT performed between 2001 and 2010. Recipients were stratified in four groups based on donor age (<60 years; 60-69 years; 70-79 years and ≥80 years) and their outcomes were compared. A total of 842 patients were included: 348 (41.3%) with donors <60 years; 176 (20.9%) with donors 60-69 years; 233 (27.7%) with donors 70-79 years and 85 (10.1%) with donors ≥80 years. There was no difference across groups in terms of early (≤30 days) graft loss, and graft survival at 1 and 5 years was 90.5% and 78.6% for grafts <60 years; 88.6% and 81.3% for grafts 60-69 years; 87.6% and 75.1% for grafts 70-79 years and 84.7% and 77.1% for grafts ≥80 years (p = 0.065). In the group ≥80 years, the 5-year graft survival was lower for HCV-positive versus HCV-negative recipients (62.4% vs. 85.6%, p = 0.034). Based on our experience, grafts from donors ≥80 years may provide favorable results but require appropriate selection and allocation policies.

Efficacy and safety of combination therapy with everolimus and sorafenib for recurrence of hepatocellular carcinoma after liver transplantation.

BACKGROUND: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice. METHODS: This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug. RESULTS: Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%). CONCLUSIONS: Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival.

Prevention by metformin of alterations induced by chronic exposure to high glucose in human islet beta cells is associated with preserved ATP/ADP ratio.

AIM: We have explored whether the insulin secretory defects induced by glucotoxicity in human pancreatic islets could be prevented by metformin and investigated some of the possible mechanisms involved. METHODS: Human pancreatic islets and INS-1E cells were cultured for 24h with or without high glucose (16.7mM) concentration in the presence or absence of therapeutical concentration of metformin and then glucose-stimulated insulin release, adenine nucleotide levels and mitochondrial complex I and II activities were measured. Islet ultrastructure was analyzed by electron microscopy. RESULTS: Compared to control islets, human islets cultured with high glucose showed a reduced glucose-stimulated insulin secretion that was associated with lower ATP levels and a lower ATP/ADP ratio. These functional and biochemical defects were significantly prevented by the presence of metformin in the culture medium, that was also able to significantly inhibit the activity of mitochondrial complex I especially in beta cells exposed to high glucose. Ultrastructural observations showed that mitochondrial volume density was significantly increased in high glucose cultured islets. The critical involvement of mitochondria was further supported by the observation of remarkably swollen organelles with dispersed matrix and fragmented cristae. Metformin was able to efficiently prevent the appearance of all these ultrastructural alterations in human islets exposed to high glucose. CONCLUSIONS: Our results show that the functional, biochemical and ultrastructural abnormalities observed in human islet cells exposed to glucotoxic condition can be significantly prevented by metformin, further highlighting a direct beneficial effect of this drug on the insulin secreting human pancreatic beta cells.

ß-Cell inflammation in human type 2 diabetes and the role of autophagy.

ß-Cell failure is crucial for the onset and progression of human type 2 diabetes, and a few studies have suggested that inflammation may play a role. Immune cell infiltration has been reported in subpopulations of islets in some cases of human type 2 diabetes, and altered gene expression of a few cytokines and chemokines has been observed in isolated islets and laser captured ß-cells from diabetic subjects. Recent observations on the links between inflammation, apoptosis and autophagy are putting the focus on the possibility that modulating the autophagic processes could protect the ß-cells from cytotoxicity induced by inflammatory mediators.

Organ sharing in the management of acute liver failure.

BACKGROUND: Liver transplantation (OLT) for acute liver failure (ALF) is associated with high morbidity and mortality rates in the early posttransplant course. An efficient organ-sharing organization may grant favorable results. METHODS: This is a retrospective analysis of prospectively collected data on patients wait listed for ALF at a single center. Patients were listed for OLT when matching King's College Criteria. Based on patients' clinical status, ABO-incompatible grafts were used. RESULTS: From January 2001 to December 2010, 37 patients were wait listed for ALF. Two patients were de-listed (5.4%) for improvement of their clinical conditions; two patients (5.4%) died on the list and 33 (89.2%) underwent OLT. Among these latter, 21 (63.6%) were Italian and 12 (36.4%) were foreign citizens, with four referred from their home country on the basis of international agreements on ALF management. Donors were procured in our region in 10 cases (30.3%), nationally in 22 (66.6%), and outside Italy in 1 (3.1%). Mean time from wait listing to OLT was 1 day (range 0-6), and seven patients received an ABO-incompatible graft. Graft and patient survivals at 1 month, 1 year, and 3 years were 78.8%, 72.7%, 66.5%, and 81.8%, 75.8%, and 72.7%, respectively. Five patients underwent retransplantation: two on postoperative day (POD) 2 for primary nonfunction of the liver graft, two on POD 8 and 95 for hepatic artery thrombosis, and one at 18 months for nonanastomotic biliary stenosis. CONCLUSIONS: Prompt referral to a OLT center and efficient organ-sharing system play a fundamental role in optimizing the outcome of the patient with ALF. Development of international organ exchange programs might further improve the results for this category of patients. In very selected cases, ABO-incompatible grafts may be a valuable resource.

Analysis of patients' needs after liver transplantation in Tuscany: a prevalence study.

BACKGROUND: The reorganization of the healthcare system in Tuscany aims at characterizing the hospitals as a place for the treatment of acute patients. This event, together with the improvement of long-term survival after orthotopic liver transplantation (OLT), calls for a management network able to ensure effective continuity of care for patient needs in the posttransplantation period. MATERIALS AND METHODS: An observational study of prevalence has been carried out with the primary objective to evaluate patients' needs and criticalities both in routine daily life and in urgency in the posttransplantation period and the capacity of the regional health system to support them. A survey, using a semi-structured questionnaire consisting of 27 questions, was administered to all patients resident in Tuscany who underwent transplantation from 2000 to 2010. The survey tool assessed the following: socio-demographic data, personal, family and social difficulties, problems emerged in the clinical routine and urgency, resolution modality, relationships with the general practitioner and the referral specialist, and services the patients would appreciate receiving in their province of residence. RESULTS: In the study, 346 patients matched the inclusion criteria of the study, 324 gave telephone consent to participate in the survey, and 225 responded (69.4%). The most frequent difficulties were as follows: depression (39.5%), difficulty in returning to work (29.3%), low income (22.6%), lack of self-sufficiency (22.6%), addictions (19.1%) (cigarette smoking 16.4%), 12.4% eating disorders, and 18.9% other difficulties (social isolation, absence of a family network, and so on). The main reasons for dissatisfaction were as follows: difficulty to obtain the required laboratory tests and lack of a reference structure at the local health facility. Few patients have a referral specialists in their area and most of them primarily refer to the Transplant Center even late after the procedure. DISCUSSION: Early diagnosis of specific conditions (depression, addiction, and eating disorders) should be implemented in the follow-up period and services such as counselling, dietary support, rehabilitation, and social services should be provided locally. An integrated management system between the transplantation center and the local facilities (hospitals, general practitioners, primary care, and laboratories) should be implemented and referral specialized centers should be identified locally.

Solvent detergent vs. fresh frozen plasma in cirrhotic patients undergoing liver transplant surgery: a prospective randomized control study.

BACKGROUND: Although orthotopic liver transplantation (OLT) is nowadays considered standard practice at experienced centres, it can still be affected by a significant risk of massive bleeding and its related complications. Solvent/detergent plasma (S/D Plasma) has been proposed as an alternative to fresh frozen plasma (FFP) to curtail such complications. This study aimed at evaluating the efficacy of S/D Plasma in OLT patients by comparing it to FFP. MATERIALS AND METHODS: Sixty-three OLT patients were randomized into two groups depending on whether they were transfused with FFP or S/D plasma. A thromboelastography-based protocol aimed at achieving and maintaining predetermined coagulation goals was used to guide plasma transfusions. At the beginning and the end of surgery, standard laboratory coagulation tests were performed together with the assessment of the VII, VIII, V, XII factors and S protein blood levels. RESULTS: The two study groups equally achieved the thromboelastography goals but with a reduced amount of transfusions in the S/D plasma group (P < 0.0001). At the end of surgery, factors V and XII and S protein blood levels were lower in the S/D plasma patients who also showed lower INR, aPTT and antithrombin III levels. CONCLUSION: In cirrhotic patients undergoing OLT, the use of S\D plasma associated with thromboelastography allows the same clinical results but with a significant reduction in the amount of plasma transfusions.

A local glucagon-like peptide 1 (GLP-1) system in human pancreatic islets.

AIMS/HYPOTHESIS: Glucagon-like peptide 1 (GLP-1) is a major incretin, mainly produced by the intestinal L cells, with beneficial actions on pancreatic beta cells. However, while in vivo only very small amounts of GLP-1 reach the pancreas in bioactive form, some observations indicate that GLP-1 may also be produced in the islets. We performed comprehensive morphological, functional and molecular studies to evaluate the presence and various features of a local GLP-1 system in human pancreatic islet cells, including those from type 2 diabetic patients. METHODS: The presence of insulin, glucagon, GLP-1, proconvertase (PC) 1/3 and PC2 was determined in human pancreas by immunohistochemistry with confocal microscopy. Islets were isolated from non-diabetic and type 2 diabetic donors. GLP-1 protein abundance was evaluated by immunoblotting and matrix-assisted laser desorption-ionisation-time of flight (MALDI-TOF) mass spectrometry. Single alpha and beta cell suspensions were obtained by enzymatic dissociation and FACS sorting. Glucagon and GLP-1 release were measured in response to nutrients. RESULTS: Confocal microscopy showed the presence of GLP-1-like and PC1/3 immunoreactivity in subsets of alpha cells, whereas GLP-1 was not observed in beta cells. The presence of GLP-1 in isolated islets was confirmed by immunoblotting, followed by mass spectrometry. Isolated islets and alpha (but not beta) cell fractions released GLP-1, which was regulated by glucose and arginine. PC1/3 (also known as PCSK1) gene expression was shown in alpha cells. GLP-1 release was significantly higher from type 2 diabetic than from non-diabetic isolated islets. CONCLUSIONS/INTERPRETATION: We have shown the presence of a functionally competent GLP-1 system in human pancreatic islets, which resides in alpha cells and might be modulated by type 2 diabetes.

Evidence for a role of frataxin in pancreatic islets isolated from multi-organ donors with and without type 2 diabetes mellitus.

Frataxin (FXN) is a mitochondrial protein involved in iron metabolism and in the modulation of reactive oxygen and/or nitrogen species production. No information is currently available as for the role of frataxin in isolated human pancreatic islets. We studied islets from pancreases of multi-organ donors with (T2DM) and without (Ctrl) Type 2 diabetes mellitus. In these islets, we determined FXN gene and protein expression by qualitative and quantitative Real-Time RT-PCR, nitrotyrosine concentration, and insulin release in response to glucose stimulation (SI). FXN gene and protein were expressed in human islets, though the level of expression was much lower in T2DM islets. The latter also had lower insulin release and higher concentration of nitrotyrosine. A positive correlation was apparent between SI and FXN gene expression, while a negative correlation was found between nitrotyrosine islet concentration and FXN expression. Transfection of Ctrl islets with siRNA FXN caused reduction of FXN expression, increase of nitrotyrosine concentration, and reduction of insulin release. In conclusion, in human pancreatic islets FXN contributes to regulation of oxidative stress and insulin release in response to glucose. In islets from T2DM patients FXN expression is reduced while oxidative stress is increased and insulin release in response to glucose impaired.

In vitro effects of mycophenolic acid on survival, function, and gene expression of pancreatic beta-cells.

Post-transplant diabetes mellitus represents an important complication of prolonged immunosuppressive treatment after solid organ transplantation. The immunosuppressive toxicity, responsible for a persistent impairment of glucose metabolism in pancreatic islet-transplanted patients, is mainly attributed to calcineurin inhibitors and steroids, while other immunosuppressive molecules (azathioprine and mycophenolic acid, MPA) are considered not to have a toxic effect. In the present study, in vitro effects of MPA have been investigated in mouse beta-cell lines (ßTC-1 and ßTC-6) and in purified human pancreatic islets. ßTC-1, ßTC-6, and human pancreatic islets were exposed to various concentrations of MPA for different times. Consequently, we evaluated the viability, the induction of apoptosis, the glucose-stimulated insulin secretion, and the expression of ß-cell function genes (Isl1, Pax6, Glut-2, glucokinase) and apoptosis-related genes (Bax and Bcl2). ßTC-1, ßTC-6, and human islets treated, respectively, for 48 and 72 h with 15-30 nM MPA showed altered islet architecture, as compared with control cells. We observed for ßTC-1 and ßTC-6 almost 70% reduction in cell viability; three to sixfold induction of TUNEL/apoptotic-positive cells quantified by FACS analysis. A twofold increase in apoptotic cells was observed in human islets after MPA exposure associated with strong inhibition of glucose-stimulated insulin secretion. Furthermore, we showed significant down-regulation of gene expression of molecules involved in ß-cell function and increase rate between Bax/Bcl2. Our data demonstrate that MPA has an in vitro diabetogenic effect interfering at multiple levels with survival and function of murine and human pancreatic ß-cells.

Alcohol drinking after liver transplantation is associated with graft injury.

AIM: This was a single-center, mixed-design, cross-sectional and retrospective study to assess the performance of the 4-item, self-reported CAGE (Cut down, Annoyed, Guilty, Eye-opener) questionnaire in predicting histology-proven alcohol-related liver graft injury (ARLGI). METHODS: A total of 316 liver transplant (LT) patients between six months and five years were enrolled. Based on previous research, problem alcohol drinking (PAD) was defined as any score ≥ 1 on the CAGE, while a cut-off of 2 was assumed for alcohol dependence (AD). RESULTS: Responders were 195, 45 (23.1%) had a CAGE score ≥ 1 and 30 (15.3%) scored ≥ 2. After controlling for confounders, PAD was associated with hyperlipidemia (P=0.01), while AD with a male gender (P=0.01), hyperlipidemia (P=0.03) and alcohol as native diagnosis (P=0.03). PAD and AD were both associated with a significantly higher prevalence of ARLGI, i.e. 53.3% and 63.3%, respectively (P<0.0001). Hepatitis C virus (HCV) patients with PAD showed more steatosis (P=0.04), portal infiltrate (P=0.03), and pericellular/perivenular fibrosis (P=0.02). The likelihood ratios for CAGE scores ranging from 0 to 4 in predicting ARLGI were 0, 5.2, 7.8, 7.8, and 100, respectively. CONCLUSION: By use of a self-report instrument we found a 23.1% prevalence of PAD and a 15.3% prevalence of AD among LT patients between six months and five years. A variable degree of ARLGI was present in 53.3% of PAD and 63.3% of AD, respectively. HCV patients with PAD had more steatosis, portal inflammation, and pericellular fibrosis. Transplant physicians might improve their ability to predict the probability for ARLGI using the CAGE.

Direct effects of rapid-acting insulin analogues on insulin signaling in human pancreatic islets in vitro.

AIMS: Studies suggest that insulin-signaling molecules are present in the pancreatic islets. For this reason, the effects of insulin glulisine, insulin aspart and regular human insulin (RHI) on the function and molecular features of isolated human pancreatic islets were investigated. METHODS: Human pancreatic islets were prepared by collagenase digestion and density-gradient purification of pancreata from multiple organ donors. Islets were then cultured for 48 h in the presence of 5.5 (normal) or 22.2 (high) mmol/L of glucose with and without glulisine, aspart and RHI (10 or 100 nmol/L). Functional (glucose-stimulated insulin secretion) and molecular (quantitative RT-PCR and immunoblot) studies were performed at the end of the different incubation conditions. RESULTS: Glucose-stimulated insulin secretion was blunted in islets cultured in 22.2 mmol/L of glucose, with no significant effects from the exogenous added insulins. In islets maintained at 5.5 mmol/L of glucose, insulin receptor (IR) expression was reduced by low RHI, while phosphatidylinositol-3 kinase p110-alpha (PI3K) was enhanced by both concentrations of glulisine and aspart, and by high RHI. In islets preexposed to high glucose, IR expression was increased by both concentrations of aspart and RHI, but not by glulisine. Glulisine at high concentration significantly (P<0.05) increased PI3K expression. Glulisine and RHI significantly increased IRS-2 phosphorylation compared with control and aspart (P<0.05). CONCLUSION: Insulin analogues have differential effects on the expression of insulin-signaling molecules in human pancreatic islets that are also dependent on the degree of glucose exposure.