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To improve the efficiency of pancreatic islet transplantation, we performed in-vitro and in-vivo experiments with isolated human pancreatic islets coated by multi-layer nano-encapsulation using differently charged polymers [chitosan and poly(sodium styrene sulfonate)] to obtain up to 9 layers. The islet coating (thickness: 104.2 ± 4.2 nm) was uniform, with ≥ 90% cell viability and well preserved beta- and alpha-cell ultrastructure. Nano-encapsulated islets maintained physiological glucose-stimulated insulin secretion by both static incubation and perifusion studies. Notably, palmitate- or cytokine-induced toxicity was significantly reduced in nano-coated islets. Xenotransplantation of nano-encapsulated islets under the kidney capsule of streptozotocin-induced C57Bl/6J diabetic mice allowed long term normal or near normal glycemia, associated with minimal infiltration of immune cell into the grafts, well preserved islet morphology and signs of re-vascularization. In summary, the multi-layer nano-encapsulation approach described in the present study provides a promising tool to effectively protect human islets both in-vitro andin-vivo conditions., (Copyright © 2018 Elsevier Inc. All rights reserved.)

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., (© Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Aims: The incidence of intraductal papillary mucinous neoplasm (IPMN) is rising and these neoplasms now represent up to 25% of resected pancreatic neoplasms. The optimal postoperative management of resected invasive IPMN is still debated in the absence of large prospective clinical trials and of validated prognostic factors in this setting. The objective of our study was to identify potential prognostic factors and to investigate the role of adjuvant therapies for patients radically resected for invasive IPMN., Methods: We retrospectively reviewed clinical and pathological data regarding a large series of patients with invasive IPMN who underwent surgical resection in the last six years at University Hospital of Pisa., Results: Sixty-four patients were considered for the analysis, thirty-three of whom received adjuvant chemotherapy with gemcitabine. In our series node involvement and high tumoral grade emerged as the major pathologic prognostic factors. Patients treated with adjuvant chemotherapy with gemcitabine experienced a longer disease-free survival than those who received surgery alone., Conclusions: Gemcitabine-based chemotherapy seems beneficial as adjuvant treatment for patients with resected invasive IPMN., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Ductal pancreatic carcinoma (DPC) is a deadly disease with an incidence of 9 cases in 100,000 people per year and a mortality rate close to 100%. Allelic losses in the long arm of chromosome 9 are commonly encountered in many human malignancies but no data are yet available about DPC. We screened 40 laser-microdissected DPC samples and 6 pre-invasive lesions for 9 microsatellite mapping markers of region 9q21.3 through 9q34.2. A small overlapping region of deletion, spanning 8 million base pairs, was identified between D9S127 and D9S105. Two genes, RSG3 and KLF4, mapped to 9q31.1 through 9q32, were further investigated. A highly significant association was found between KLF4 gene expression levels and genomic status. Similarly, absence of immunohistochemical expression of KLF4 protein was found in 86.8% cases of DPC (33/38). Overexpression of KLF4 in a human pancreatic carcinoma cell line induced a significant decrease in the proliferation associated with up-regulation of p21 and the down-regulation of cyclin D1. In conclusion, we identified a novel oncosuppressor region located at the 9q 31.1-3 locus that is lost in DPC at high frequency. Loss of KLF4 expression is closely related to the genomic loss, and its restoration inhibits cancer cell proliferation, suggesting a key suppressor role in pancreatic tumorigenesis., (Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Duodenal graft complications (DGC) occur frequently after pancreas transplantation but rarely cause graft loss. Graft pancreatectomy, however, may be required when DGC compromise recipient's safety. We herein report on two patients with otherwise untreatable DGC in whom the entire pancreas was salvaged by means of total duodenectomy with enteric drainage of both pancreatic ducts. The first patient developed recurrent episodes of enteric bleeding, requiring hospitalization and blood transfusions, starting 21 months after transplantation. The disease causing hemorrhage could not be defined, despite extensive investigations, but the donor duodenum was eventually identified as the site of bleeding. The second patient was referred to us with a duodenal stump leak, 5 months after transplantation. Two previous surgeries had failed to seal the leak, despite opening a diverting stoma above the duodenal graft. Thirty-nine and 16 months after total duodenectomy with dual duct drainage, respectively, both patients are insulin-independent and free from abdominal complaints. Magnetic resonance pancreatography shows normal ducts both basal and after intravenous injection of secretin. The two cases presented herein show that when DGC jeopardize pancreas function or recipient safety, total duodenectomy with enteric duct drainage may become an option.

Choroid plexus carcinomas in four dogs (three male, one female) aged small middle 2.5 to 10 years, were examined by light microscopy and immunohistochemistry. The dogs showed progressive neurological signs including ataxia, seizures, vestibular disease and cranial nerve deficits, lasting for several months in some cases. Primary tumours were localized in the lateral (one case), third (one case), and fourth (two cases) ventricles. Hydrocephalus was evident at post-mortem examination in one case. In two cases the neoplastic cells closely resembled the structure of normal choroid plexus, with a distinct papillary pattern, composed of well-differentiated columnar epithelium. In the other two cases, cellular pleomorphism, nuclear atypia, increased mitotic activity and necrosis were observed. In all cases, dissemination of neoplastic cell clusters was detected within the subarachnoid space or the ventricular cavity. Immunohistochemical examination showed a multifocal labelling pattern for pankeratin and cytokeratin AE1 and diffuse vimentin positivity in poorly differentiated tumours. Well-differentiated choroid plexus carcinomas showed multifocal immunoreactivity for cytokeratin AE3, multifocal to diffuse immunoreactivity for vimentin and occasional positivity for carcinoembryonic antigen. Epithelial membrane antigen, Ber EP4 and S-100 were negative in all cases. Glial fibrillary acidic protein labelling occurred only in a single, poorly differentiated tumour. Occasional reactions for proliferating cell nuclear antigen and MIB-1 were seen in two cases. It was concluded that at least two morphological and possibly phenotypic subtypes (well-differentiated and anaplastic) of choroid plexus carcinoma of the dog could be identified.

The aim of this study was to establish the presence and the consistency of different cognitive profiles in AD patients taking into consideration the severity of mental impairment. Therefore we stratified 679 neuropsychological observations on 119 probable AD patients followed longitudinally on the basis of overall degree of cognitive impairment. To compare performance on tests with different score ranges we transformed raw test scores into coefficients; to summarize our results in terms of language versus visuo-spatial performance we computed indices of prevalent impairment of performance (IPIP) by subtracting the coefficients for constructional praxis from coefficients for language-related tests. Finally, we converted these indices into z-scores for each level of mental decline to identify patients with generalized, language (L) or visuo-spatial (V) prevalent impairment. The latter, 30% of the sample, can be detected at all stages of dementia. There was a higher percentage of males among language impaired patients (P<0.05). Approximately half of patients with L/V prevalent impairment continued to show such a focality when followed longitudinally. The groups did not differ in the annual rate of cognitive decline.

We examined selective MRI features (localization and degree of white matter abnormalities, cortical and subcortical atrophy) in relation to cognitive decline in patients with cerebrovascular disease (CVD) and leukoaraiosis (LA). We enrolled 6 female and 18 male CVD patients (mean age 66.2 +/- 6.6 years) whose Magnetic Resonance Images (MRI) revealed LA and who displayed a history of stroke or TIA; none showed signs of cortical infarcts or normal pressure hydrocephalus. Two blind raters independently scored MRI scans with a high level of agreement. All patients underwent extensive clinico-neuropsychological assessment upon admission to the study and 19 were followed for an average of 48 +/- 7.6 months. Twelve patients were initially classified as non-demented and 12 as demented. Three years later, one in the former group had become demented and mental impairment had worsened for 6 patients in the latter group; these 7 subjects were labeled as "decliners". Ventricular indexes were significantly higher in the demented group and correlated with severity of mental impairment, while the degree of LA was similar in demented and non-demented subjects. Neither white matter lesions nor sulcal and ventricular enlargement differed statistically between decliners and non-decliners.