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31.
BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.  相似文献   
32.

Objective

To calculate the prevalence of common gain of function gene mutations in patients with different clinical manifestations of venous thromboembolism.

Design and setting

Case–control study in two hospitals in Italy.

Participants

387 patients with venous thromboembolism and 286 controls.

Main measures

Factor V (FV) Leiden, factor II (FII) A20210 and JAK2 V617F mutations.

Results

Among patients with deep vein thrombosis in one leg, 23 (20.9%) carried FV Leiden and FII A20210 mutations. Similar figures were observed in patients with cerebral vein thrombosis (CVT; n = 9; 20.0%) and in patients presenting with splanchnic vein thrombosis (SVT; n = 26; 18.7%). A lower prevalence was obtained in patients with retinal vein thrombosis (n = 11; 11.8%). The JAK2 F617 mutant allele was found in 27 (21.1%) patients with SVT, but in none of the patients presenting with a thrombotic event from different districts. 13 of the 27 JAK2 V617F‐positive subjects with SVT were previously known to have a myeloproliferative disease (MPD). Three other patients had a diagnosis of MPD after the occurrence of the thrombotic event.

Conclusion

Carriership of FV Leiden or FII A20210 mutations identifies an at‐risk condition for venous thrombosis in the lower extremities, SVT or CVT. In patients with SVT, screening for the JAK2 V617F mutation may be useful in recognising patients who should be carefully observed for the subsequent development of overt MPD. Thus, genetic tests may play a different role, various clinical manifestations of venous thromboembolism being associated with distinct risk profiles.Venous thrombosis is the third most common cardiovascular affliction after ischaemic heart disease and stroke.1 It is common in Caucasians, affecting 1 in 1000 individuals every year, and is strongly associated with life‐threatening pulmonary embolism. The pathogenesis of venous thrombosis is multifactorial, involving acquired and genetic factors. In addition to circumstantial predisposing factors (eg, surgery, pregnancy, immobilisation and malignancy), genetic predisposition due to molecular abnormalities of components of the coagulation pathway have been found in subjects who had had thromboembolic disease.2 Abnormalities within the gene loci encoding for natural anticoagulants (antithrombin, protein C and protein S) and for fibrinogen have been shown to be rather uncommon risk factors for venous thrombosis.3 In patients of European ancestry, common gain‐of‐function mutations within the gene of the coagulation factor V (FV Leiden mutation) and the factor II (FII) gene (a G→A transition at nucleotide position 20210) have been shown to account for a large number of cases of thromboembolism.2,3 Recently, the JAK2 V617F mutation, an acquired somatic event occurring in most patients with polycythaemia vera (PV) and in about half of the patients with essential thrombocythaemia (ET) or myelofibrosis (MF),4,5,6,7,8 has been found in a high proportion of patients with Budd–Chiari syndrome9 and in patients without cirrhosis with portal and mesenteric venous thrombosis, a heterogeneous group of disorders.10Thus, the high frequency of common mutations in patients presenting with venous thromboembolism raised the hypothesis that it can be considered as a feasible and practical approach for the identification of predisposing genetic risk factors. Genetic test results can better inform individuals about their risk of recurrence and appropriated tailored strategies for the prevention of venous thrombosis.However, depending on the different clinical manifestations of venous thromboembolism, the prevalence of inherited coagulation abnormalities varies, suggesting pathogenic differences.11,12,13 These data support the hypothesis that mechanistic differences are involved in the pathogenesis of thrombosis in different clinical settings. Thus, before considering whether it is advisable to investigate a subject for inherited risk factors, we need to know the prevalence of these risk factors in different clinical settings.We, therefore, calculated the prevalence of inherited thrombophilic risk factors in a large cohort of patients referred for a thrombophilic investigation with different clinical manifestations of venous thromboembolism.  相似文献   
33.
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35.

INTRODUCTION

Surgical stress in the presence of fasting worsens the catabolic state, causes insulin resistance and may delay recovery. Carbohydrate rich drinks given preoperatively may ameliorate these deleterious effects. A systematic review was undertaken to analyse the effect of preoperative carbohydrate loading on insulin resistance, gastric emptying, gastric acidity, patient wellbeing, immunity and nutrition following surgery.

METHODS

All studies identified through PubMed until September 2011 were included. References were cross-checked to ensure capture of cited pertinent articles.

RESULTS

Overall, 17 randomised controlled trials with a total of 1,445 patients who met the inclusion criteria were identified. Preoperative carbohydrate drinks significantly improved insulin resistance and indices of patient comfort following surgery, especially hunger, thirst, malaise, anxiety and nausea. No definite conclusions could be made regarding preservation of muscle mass. Following ingestion of carbohydrate drinks, no adverse events such as apparent or proven aspiration during or after surgery were reported.

CONCLUSIONS

Administration of oral carbohydrate drinks before surgery is probably safe and may have a positive influence on a wide range of perioperative markers of clinical outcome. Further studies are required to determine its cost effectiveness.  相似文献   
36.

Introduction

Magnetic resonance cholangiopancreatography (MRCP) is not a routine investigation to exclude choledocholithiasis unless there is clinical or biochemical suspicion of common bile duct (CBD) stones. This study attempted to determine which radiological or serological parameters best predicted CBD stones.

Methods

All patients undergoing MRCP from 2005 to 2011 were selected. Patients with pancreatitis were excluded. Liver function tests (LFTs) at admission and prior to MRCP were recorded, as was abdominal ultrasonography and MRCP results. Parameters measured routinely on LFTs included alkaline phosphatase (ALP), alanine transaminase (ALT) and bilirubin. Receiver operating characteristic curve area analysis (area under the curve [AUC]) and chi-squared analysis were undertaken.

Results

Overall, 195 patients were identified, 71 of whom had CBD stones on MRCP. Raised ALP levels on admission demonstrated a correlation with CBD stones (AUC: 0.619, odds ratio [OR]: 3.16, p=0.06). At ultrasonography, a dilated CBD (OR: 3.76, p<0.001) and intrahepatic duct dilation (OR: 5.56, p<0.001) were highly significant predictors. However, only 37% of patients had a dilated CBD on ultrasonography. Ongoing elevation of LFT parameters, particularly ALP (AUC: 0.707, OR: 4.64, p<0.001) and ALT (AUC: 0.646, OR: 5.40, p<0.001), displayed a significant correlation with CBD stones.

Conclusions

Ongoing (even if minor) elevations of liver function test parameters should prompt the need to exclude CBD stones even in the presence of a normal CBD diameter on ultrasonography.  相似文献   
37.
38.
Vitale  Giovanni  Dicitore  Alessandra  Barrea  Luigi  Sbardella  Emilia  Razzore  Paola  Campione  Severo  Faggiano  Antongiulio  Colao  Annamaria  Albertelli  Manuela  Altieri  Barbara  Bottiglieri  Filomena  De Cicco  Federica  Di Molfetta  Sergio  Fanciulli  Giuseppe  Feola  Tiziana  Ferone  Diego  Ferraù  Francesco  Gallo  Marco  Giannetta  Elisa  Grillo  Federica  Grossrubatscher  Erika  Guadagno  Elia  Guarnotta  Valentina  Isidori  Andrea M.  Lania  Andrea  Lenzi  Andrea  Calzo  Fabio Lo  Malandrino  Pasquale  Messina  Erika  Modica  Roberta  Muscogiuri  Giovanna  Pes  Luca  Pizza  Genoveffa  Pofi  Riccardo  Puliani  Giulia  Rainone  Carmen  Rizza  Laura  Rubino  Manila  Ruggieri  Rosa Maria  Sesti  Franz  Venneri  Mary Anna  Zatelli  Maria Chiara 《Reviews in endocrine & metabolic disorders》2021,22(3):511-525

Gut microbiota is represented by different microorganisms that colonize the intestinal tract, mostly the large intestine, such as bacteria, fungi, archaea and viruses. The gut microbial balance has a key role in several functions. It modulates the host’s metabolism, maintains the gut barrier integrity, participates in the xenobiotics and drug metabolism, and acts as protection against gastro-intestinal pathogens through the host’s immune system modulation. The impaired gut microbiota, called dysbiosis, may be the result of an imbalance in this equilibrium and is linked with different diseases, including cancer. While most of the studies have focused on the association between microbiota and gastrointestinal adenocarcinomas, very little is known about gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). In this review, we provide an overview concerning the complex interplay between gut microbiota and GEP NENs, focusing on the potential role in tumorigenesis and progression in these tumors.

  相似文献   
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Iron overload in β‐thalassemia major (TM) typically results in iron‐induced cardiomyopathy, liver disease, and endocrine complications. We examined the incidence and progression of endocrine disorders (hypothyroidism, diabetes, hypoparathyroidism, hypogonadism), growth and pubertal delay, and bone metabolism disease during long‐term deferasirox chelation therapy in a real clinical practice setting. We report a multicenter retrospective cohort study of 86 transfusion‐dependent patients with TM treated with once daily deferasirox for a median duration of 6.5 years, up to 10 years. No deaths or new cases of hypothyroidism or diabetes occurred. The incidence of new endocrine complications was 7% (P = 0.338, for change of prevalence from baseline to end of study) and included hypogonadism (n = 5) and hypoparathyroidism (n = 1). Among patients with hypothyroidism or diabetes at baseline, no significant change in thyroid parameters or insulin requirements were observed, respectively. Mean lumbar spine bone mineral density increased significantly (P < 0.001) and the number of patients with lumbar spine osteoporosis significantly decreased (P = 0.022) irrespective of bisphosphonate therapy, hormonal replacement therapy, and calcium or vitamin D supplementation. There were no significant differences in the number of pediatric patients below the 5th centile for height between baseline and study completion. Six pregnancies occurred successfully, and four of them were spontaneous without ovarian stimulation. This is the first study evaluating endocrine function during the newest oral chelation therapy with deferasirox. A low rate of new endocrine disorders and a stabilization of those pre‐exisisting was observed in a real clinical practice setting. Am. J. Hematol. 89:1102–1106, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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