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941.
Pancreas transplantation consistently induces insulin-independence in beta-cell-penic diabetic patients, but at the cost of major surgery and life-long immunosuppression. One year after grafting, patient survival rate now exceeds 95?% across recipient categories, while insulin independence is maintained in some 85?% of simultaneous pancreas and kidney recipients and in nearly 80?% of solitary pancreas transplant recipients. The half-life of the pancreas graft currently averages 16.7?years, being the longest among extrarenal grafts, and substantially matching the one of renal grafts from deceased donors. The difference between expected (100?%) and actual insulin-independence rate is mostly explained by technical failure in the postoperative phase, and rejection in the long-term period. Death with a functioning graft remains a further major issue, especially in uremic patients who have undergone prolonged periods of dialysis. Refinements in graft preservation, surgical techniques, immunosuppression, and prophylactic treatments are expected to further improve the results of pancreas transplantation.  相似文献   
942.
943.
Research questionWilson's disease (WD) is a disorder of copper metabolism that can cause hormonal alterations. The impact of WD and its therapies on fertility is not well defined. The aim of this study was to evaluate ovarian reserve and sperm parameters in long-term treated WD patients with hepatic onset.DesignWD patients with hepatic onset treated for at least 5 years were compared with healthy controls. Men underwent spermiogram and sperm DNA fragmentation (SDF) analysis. Women were tested for serum FSH, anti-Müllerian hormone (AMH) and sonographic antral follicle count (AFC) in the early follicular phase. Ovulation was monitored with ultrasound and progesterone serum concentrations in the luteal phase.ResultsThe WD group included 26 patients (12 males), the control group 19 subjects (9 males). All patients apart from four (one male) were responders to WD treatment. Sperm count and morphology were comparable between cases and controls. Sperm motility (total and after 1 h) was significantly lower in cases (44.78 ± 21.65%; 47.85 ± 21.52%) than controls (61.88 ± 11.03; 69.44 ± 11.02%, P = 0.03 and 0.01, respectively). The only non-responder had severe oligo-astheno-teratozoospermia. SDF values were normal in cases and controls. AMH, AFC and FSH did not differ between cases and controls. LH was significantly lower in cases (3.36 ± 1.65 mIU/ml) than controls (6.25 ± 1.03 mIU/ml, P < 0.0001). A non-responder woman who developed neurological signs had a 7-year history of infertility.ConclusionsWD patients with hepatic onset, diagnosed early and treated, have no impairment in fertility potential even if males show reduced sperm motility and females lower LH values. Only patients with poor disease control have some evidence of impaired fertility.  相似文献   
944.
Three years ago we described laparoscopic placement of biliary stems as an adjunct to laparoscopic common bile duct exploration (LCBDE) in 16 patients. We now present a modification of our technique and experience with 48 additional patients. Laparoscopic cholecystectomy with intraoperative fluorocholangiography (LC/IOC) performed in 372 consecutive patients during a 36-month period revealed common bile duct stones (CBDS) in 48 patients (12.9%). In this series, LCBDE was not performed and no attempt was made to clear CBDS prior to transcystic stent placement. Stent placement added 9 to 26 minutes of operative time to LC/IOC alone. Forty-four patients (92%) were discharged after surgery and four (8%) were observed overnight. Outpatient endoscopic retrograde cholangiopancreatography 1 to 4 weeks later succeeded in clearing CBDS in all patients. All stents were retrieved without difficulty and 3- to 36-month follow-up demonstrates no surgical, endoscopic, or stent-related complications to date. Laparoscopic biliary stent placement for the treatment of CBDS is a safe, rapid, technically less challenging alternative to existing methods of LCBDE. It preserves the benefits of minimally invasive surgery for patients, and virtually assures success of postoperative endoscopic retrograde cholangiopancreatography with complete stone clearance. Presented at the Forty-First Annual Meeting of The Society for Surgery of the Alimentary Tract, San Diego, Calif., May 2l–24, 2000 (poster presentation).  相似文献   
945.
(1) Background: As the pandemic months progress, more and more evidence shows that the placenta acts as a “barrier” to SARS-CoV-2, although rare cases of vertical transmission have been described. (2) Methods: In an attempt to investigate whether the symptoms’ severity was related to different placental histological characteristics and the immune microenvironment, we subdivided 29 placentas from 29 mothers positive for SARS-CoV-2 into two groups, depending on the symptomatology (moderate/severe vs. asymptomatic/mild), performing immunohistochemical investigations for CD4 + and CD8 + T lymphocytes, as well as for CD68 + macrophage. We also evaluated the immuno-expression of the ACE2 receptor at the placental level. These two groups were compared to a control group of 28 placentas from 28 SARS-CoV-2-negative healthy mothers. (3) Results: The symptoms (likely to be related to viremia) were statistically significantly correlated (p < 0.05) with histopathological changes, such as maternal malperfusion, decidual arteriopathy, blood vessel thrombus of fetal relevance. Furthermore, the immuno-expression of ACE2 was significantly lower in SARS-CoV-2-positive groups vs. control group (p = 0.001). (4) Conclusions: There is still much to study and discover regarding the relationship between SARS-CoV-2 and histological changes in placentas and how the latter might contribute to various neonatal clinical outcomes, such as prematurity.  相似文献   
946.
Food allergies are an increasing health problem worldwide. They are multifactorial diseases, in which the genome alone does not explain the development of the disease, but a genetic predisposition and various environmental factors contribute to their onset. Environmental factors, in particular nutritional factors, in the early stages of life are recognized as key elements in the etiology of food allergies. There is growing evidence advising that nutrition can affect the risk of developing food allergies through epigenetic mechanisms elicited by the nutritional factors themselves or by modulating the gut microbiota and its functional products. Gut microbiota and postbiotics can in turn influence the risk of food allergy development through epigenetic mechanisms. Epigenetic programming accounts not only for the short-term effects on the individual’s health status, but also for those observed in adulthood. The first thousand days of life represent an important window of susceptibility in which environmental factors, including nutritional ones, can influence the risk of developing allergies through epigenetic mechanisms. From this point of view, it represents an interesting window of opportunity and intervention. This review reports the main nutritional factors that in the early stages of life can influence immune oral tolerance through the modulation of epigenetic mechanisms.  相似文献   
947.
Background: Body weight (BW) loss is an essential therapeutic goal in type 2 diabetes (T2D). Glucagon-like peptide-1 receptor agonists are effective in reducing BW, but their effect on body composition has not yet been fully explored. The study aim was to assess the impact of Semaglutide on body composition in patients with T2D. Methods: Forty patients with T2D were treated with subcutaneous Semaglutide and evaluated at the baseline (T0) and after three (T3) and six (T6) months. Body composition was assessed by a phase-sensitive bioimpedance analyzer. Visceral adipose tissue (VAT) thickness was also measured with an ultrasonographic method (US-VAT). Anthropometric variables, muscular strength, and laboratory tests were analyzed and compared. Results: A significant decrease in VAT, the fat mass index (FMI), and BW loss was observed at all observation times. US-VAT, the skeletal mass index (SMI), the fat-free mass index (FFMI), waist circumferences, and glycated hemoglobin had lessened after three months and remained stable at T6. No variations in muscle strength, the muscle quality index, and body water were found. Discussion: In a real-life setting, Semaglutide provided significant weight loss mainly due to a reduction in the FMI and VAT, with non-clinically relevant changes in the SMI, the FFMI, and muscle strength. Most importantly, the results were obtained after three months of treatment and persisted thereafter.  相似文献   
948.
949.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a pathogen with enteric tropism. We compared the clinical, biochemical and radiological features of children hospitalized for acute SARS-CoV-2 infection, classified in two groups based on the presence of diarrhea. Logistic regression analyses were used to investigate the variables associated with diarrhea. Overall, 407 children were included in the study (226 males, 55.5%, mean age 3.9 ± 5.0 years), of whom 77 (18.9%) presented with diarrhea, which was mild in most cases. Diarrhea prevalence was higher during the Alpha (23.6%) and Delta waves (21.9%), and in children aged 5–11 y (23.8%). Other gastrointestinal symptoms were most commonly reported in children with diarrhea (p < 0.05). Children with diarrhea showed an increased systemic inflammatory state (higher C-reactive protein, procalcitonin and ferritin levels, p < 0.005), higher local inflammation as judged by mesenteric fat hyperechogenicity (adjusted Odds Ratio 3.31, 95%CI 1.13–9.70) and a lower chance of previous immunosuppressive state (adjusted Odds Ratio 0.19, 95%CI 0.05–0.70). Diarrhea is a frequent feature of pediatric COVID-19 and is associated with increased systemic inflammation, which is related to the local mesenteric fat inflammatory response, confirming the implication of the gut not only in multisystem inflammatory syndrome but also in the acute phase of the infection.  相似文献   
950.
Transforming growth factor alpha (TGF-alpha) is a 50-amino acid peptide, previously demonstrated only in transformed cell lines and human tumors, which is structurally homologous to epidermal growth factor (EGF). TGF-alpha expression in keratinocytes from normal individuals, patients with psoriasis, and patients with malignant skin diseases was investigated using an mAb raised against synthetic human TGF-alpha. mAb A1.5 reacted with TGF-alpha, but not EGF, in a sensitive ELISA. Keratinocytes in eight nodular basal cell carcinomas, one morpheic basal cell carcinoma, and one squamous cell carcinoma demonstrated intense membranous immunoperoxidase staining with mAb A1.5. Of even greater interest was the observation that the overlying normal epidermis, as well as the epidermis from five normal skin specimens, were stained by the mAb. Keratinocytes in plaques from 18 psoriasis patients were more intensely stained than those from normal skin. Cultured normal keratinocytes demonstrated membranous staining with mAb A1.5. Absorption of mAb A1.5 with synthetic human TGF-alpha completely removed the reactivity of mAb A1.5 with both basal cell tumors and normal epidermis. The demonstration of TGF-alpha in normal keratinocytes suggests that it plays a role in normal keratinocyte growth, wound healing, and in the pathogenesis of acanthosis.  相似文献   
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