Post-transplant diabetes mellitus in Canadian liver and renal transplant recipients.

BACKGROUND: Post-transplant diabetes mellitus (PTDM) occurs in 10%-40% of liver and renal transplant recipients. Whether the risk factors for PTDM in liver and renal transplant recipients are similar and whether Indigenous Canadians, who have a high underlying prevalence of diabetes mellitus (DM), are at increased risk of developing PTDM have yet to be determined. OBJECTIVE: To describe and compare those variables associated with PTDM in adult Canadian liver and renal transplant recipients. METHODS: A retrospective chart review of adult liver and renal transplant recipients attending four transplant follow-up clinics in three Canadian provinces was undertaken. RESULTS: De novo PTDM was diagnosed in 184/905 (20.3%) liver and 179/390 (45.9%) renal transplant recipients. Older age, higher pre-transplant BMI, underlying immune-mediated liver disease, lower trough tacrolimus levels and longer duration of follow-up were independently associated with PTDM in liver transplant recipients and non-Caucasian race, higher pre-transplant BMI, and incidence of organ rejection in renal transplant recipients. Compared with Caucasians, Indigenous Canadians who had undergone renal transplantation had a significantly increased prevalence of PTDM (56.5% versus 40.0%, p = 0.035). The prevalence of PTDM in liver transplant recipients was similar in Indigenous Canadians and Caucasians (27.9% versus 20.1%, p = 0.215). CONCLUSIONS: The variables associated with PTDM differ in liver and renal transplant recipients. Compared with Caucasians, Indigenous Canadians undergoing renal transplantation are at increased risk of developing PTDM.

Myeloid Sarcoma Presenting as Obstructive Jaundice.

Myeloid sarcoma (MS) is a rare solid neoplasm that consists of extramedullary myeloid precursor cells. Generally, it is associated with underlying acute myeloid leukemia (AML) or AML yet to manifest clinically. It can present as isolated, also known as primary MS without evidence of AML or other myeloproliferative neoplasms. We present the case of a previously healthy 36-year-old male, who was admitted to hospital with new-onset painful obstructive jaundice and final diagnosis of isolated MS was made after through investigations. We are pleased to report that he had favorable response to the treatment and remains well.

Combination antiretroviral therapy improves recurrent primary biliary cholangitis following liver transplantation.

Recurrent primary biliary cholangitis (rPBC) is frequent following liver transplantation and associated with increased morbidity and mortality. It has been argued that rPBC behaves like an infectious disease because more potent immunosuppression with tacrolimus is associated with earlier and more severe recurrence. Prophylactic ursodeoxycholic acid is an established therapeutic option to prevent rPBC, whereas the role of second line therapies, such as obeticholic acid and bezafibrate in rPBC, remains largely unexplored. To address the hypothesis that a human betaretrovirus plays a role in the development of PBC, we have tested antiretroviral therapy in vitro and conducted randomised controlled trials showing improvements in hepatic biochemistry. Herein, we describe the utility of combination antiretroviral therapy to manage rPBC in two patients treated with open label tenofovir/emtricitabine-based regimens in combination with either lopinavir or raltegravir. Both patients experienced sustained biochemical and histological improvement with treatment, but the antiretroviral therapy was associated with side effects.

Can We Add the History of the Nonoperative Therapy of Varices to Other Success Chapters of Modern Medicine?

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Protein phosphatase role in adenosine A1 receptor-induced AMPA receptor trafficking and rat hippocampal neuronal damage in hypoxia/reperfusion injury.

Adenosine signaling via A1 receptor (A1R) and A2A receptor (A2AR) has shown promise in revealing potential targets for neuroprotection in cerebral ischemia. We recently showed a novel mechanism by which A1R activation with N(6)-cyclopentyl adenosine (CPA) induced GluA1 and GluA2 AMPA receptor (AMPAR) endocytosis and adenosine-induced persistent synaptic depression (APSD) in rat hippocampus. This study further investigates the mechanism of A1R-mediated AMPAR internalization and hippocampal slice neuronal damage through activation of protein phosphatase 1 (PP1), 2A (PP2A), and 2B (PP2B) using electrophysiological, biochemical and imaging techniques. Following prolonged A1R activation, GluA2 internalization was selectively blocked by PP2A inhibitors (okadaic acid and fostriecin), whereas inhibitors of PP2A, PP1 (tautomycetin), and PP2B (FK506) all prevented GluA1 internalization. Additionally, GluA1 phosphorylation at Ser831 and Ser845 was reduced after prolonged A1R activation in hippocampal slices. PP2A inhibitors nullified A1R-mediated downregulation of pSer845-GluA1, while PP1 and PP2B inhibitors prevented pSer831-GluA1 downregulation. Each protein phosphatase inhibitor also blunted CPA-induced synaptic depression and APSD. We then tested whether A1R-mediated changes in AMPAR trafficking and APSD contribute to hypoxia-induced neuronal injury. Hypoxia (20 min) induced A1R-mediated internalization of both AMPAR subunits, and subsequent normoxic reperfusion (45 min) increased GluA1 but persistently reduced GluA2 surface expression. Neuronal damage after hypoxia-reperfusion injury was significantly blunted by pre-incubation with the above protein phosphatase inhibitors. Together, these data suggest that A1R-mediated protein phosphatase activation causes persistent synaptic depression by downregulating GluA2-containing AMPARs; this previously undefined role of A1R stimulation in hippocampal neuronal damage represents a novel therapeutic target in cerebral ischemic damage.