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101.
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BackgroundThe Clavien-Dindo classification (CDC) system and Comprehensive Complication Index (CCI®) are both widely used methods for reporting the burden of postoperative complications. This study aimed to compare the accuracy of the CDC and CCI® in predicting outcomes associated with pancreatic surgery.MethodsThe CCI® and CDC were applied to 668 patients who underwent pancreatic resection. Length of postoperative stay (LOS) was chosen as the primary outcome variable. The comparison between CCI® and CDC was made with the Spearman test, reporting þs with standard error (SE) and logistic regression, reporting the Odds Ratio (OR) and Area Under the Curve with SE.ResultsThe median value with the interquartile range (IQR) of CCI® was 20.9 (0–29.6). Both CCI® (þs = 0.609) and CDC (0.590) were significantly (P < 0.001) correlated to LOS. CCI (OR 1.056 and OR 1.052) and CDC (OR 1.978, and OR 1.994) predicted (P < 0.001) LOS over the median and 75th percentile. The accuracy of CCI® was superior to CDC for LOS over 50th (0.785 vs. 0.740; P = 0.004) and over 75th (0.835 vs. 0.761; P < 0.001) percentile.ConclusionThe accuracy of CCI® in measuring the complicated postoperative course was superior to CDC, correctly classifying eight patients every ten tested.  相似文献   
103.
Brush border Myosin Ia (MYO1A) has been shown to be frequently mutated in colorectal tumors with microsatellite instability (MSI) and to have tumor suppressor activity in intestinal tumors. Here, we investigated the frequency of frameshift mutations in the A8 microsatellite in exon 28 of MYO1A in MSI gastric and endometrial tumors and found a high mutation rate in gastric (22/47; 46.8%) but not endometrial (3/48; 6.2%) tumors. Using a regression model, we show that MYO1A mutations are likely to confer a growth advantage to gastric, but not endometrial tumors. The mutant MYO1A7A protein was shown to lose its membrane localization in gastric cancer cells and a cycloheximide‐chase assay demonstrated that the mutant MYO1A7A protein has reduced stability compared to the wild type MYO1A. Frequent MYO1A promoter hypermethylation was also found in gastric tumors. Promoter methylation negatively correlates with MYO1A mRNA expression in a series of 58 non‐MSI gastric primary tumors (Pearson's r = ?0.46; p = 0.0003) but not in a cohort of 54 non‐MSI endometrial tumors and treatment of gastric cancer cells showing high MYO1A promoter methylation with the demethylating agent 5‐aza‐2′‐deoxycytidine, resulted in a significant increase of MYO1A mRNA levels. We found that normal gastric epithelial cells, but not normal endometrial cells, express high levels of MYO1A. Therefore, when considered together, our findings suggest that MYO1A has tumor suppressor activity in the normal gastric epithelium but not in the normal endometrium and inactivation of MYO1A either genetically or epigenetically may confer gastric epithelial cells a growth advantage.  相似文献   
104.
There are conflicting evidence regarding the association of hypertension with Alzheimer's disease (AD), and so far it is still unexplored whether increased blood pressure levels can be mechanistically related to the pathophysiology of AD. Since the deposition of beta-amyloid (A beta) in brain represents the first pathogenetic event in the onset of AD, in this study we investigated the role of hypertension in the brain deposition of A beta. We analyzed two independent mouse models of hypertension. In both models we observed an increased permeability of blood-brain barrier in cortex and hippocampus. More interestingly, in the same areas hypertensive mice showed a marked positivity to anti-A beta antibodies and the presence of A beta-like fragments. Finally, we analyzed mice after passive immunotherapy with anti-A beta IgG. We observed that this latter approach determined a markedly reduced A beta immunopositivity in both cortex and hippocampus. Our study demonstrates that chronic hypertension determines an impairment of the blood-brain barrier permeability with deposition of A beta in brain tissue and that passive immunotherapy prevents this latter phenomenon.  相似文献   
105.
INTRODUCTION: In previous studies we have consistently shown a significant increase of platelet reactivity after exercise in patients with obstructive coronary artery disease (CAD). We also observed a significant individual variability in the response to exercise of platelet reactivity in these patients. Whether exercise-induced changes in platelet reactivity correlate with changes in platelet membrane receptors in patients with CAD is unknown. METHODS: We studied 26 patients with stable CAD and 10 matched healthy controls who underwent a symptom-limited treadmill exercise stress test. Venous blood samples were collected at rest and within 5 min of peak exercise. Platelet reactivity was measured by the PFA-100 method as time to occlude (closure time, CT) a ring coated with collagen/adenosine diphosphate (C/ADP). Platelet expression of glycoprotein (GP) IIb/IIIa, in both global (CD41) and active form (PAC-1), and P-selectin (CD62P) and formation of leukocyte-platelet aggregates were assessed by flow cytometry. RESULTS: After exercise CT did not change in controls (85.4+/-12 to 84.0+/-9 s, p=0.37), whereas it decreased in CAD patients (98.8+/-24 to 91.4+/-25 s, p<0.001). After exercise, CD41 and PAC-1 platelet expression increased significantly in CAD patients (p=0.04 for both), but not in controls (p=0.39 and p=0.98, respectively). To evaluate the relationship between the response to exercise of platelet reactivity and of platelet receptor expression, CAD patients were divided into two groups: CAD group 1 (16 patients, decrease in CT >5 s after exercise) and CAD group 2 (10 patients no increase in platelet reactivity after exercise). CD41 and PAC-1 expression increased in CAD group 1 (p=0.008 and p=0.026, respectively) but not in CAD group 2 (p=0.39 and p=0.50, respectively). No significant differences were observed between the 2 groups for changes in CD62P and leukocyte-platelet aggregates. CONCLUSIONS: Our data show that, in patients with stable CAD, an increased platelet reactivity to C/ADP stimulation after exercise, as assessed by the PFA-100 method, is specifically associated with an increased expression of platelet GP IIb/IIIa receptor.  相似文献   
106.
Patients with myeloproliferative disorders (MPD) are known to have some abnormalities of platelet glycoproteins (Gp). Quantitative changes of the Gp Ib, IIb-IIIa, and/or their glucidic content have been reported. Since the Gp IIb-IIIa complex plays a major role in fibrinogen binding by activated platelets, we measured the platelet fibrinogen affinity in nine patients with polycythemia vera (PV) and one subject with chronic myeloid leukemia (CML) by the aggregometric method of Marguerie. In all patients the Kd of the platelet fibrinogen reaction was significantly decreased as compared to controls, with evidence in two cases with PV of a heterogeneity of platelet-fibrinogen receptor sites. The measurement of 125I-labeled fibrinogen-platelet binding, performed in seven patients (five PV and two CML), showed receptor populations with increased (Kd1 = 0.58 + 0.3 X 10(7) mol/L) and normal affinity (Kd2 = 5.12 + 3.1 X 10(7) mol/L). These results demonstrate a heterogeneity of platelet-fibrinogen receptors in these patients and may explain the thrombotic diathesis of MPD subjects.  相似文献   
107.
Families with 3 different syndromes characterized by autosomal dominant inheritance of low platelet count and giant platelets were studied. Fechtner syndrome is an autosomal-dominant variant of Alport syndrome manifested by nephritis, sensorineural hearing loss, and cataract formation in addition to macrothrombocytopenia and polymorphonuclear inclusion bodies. Sebastian platelet syndrome is an autosomal-dominant macrothrombocytopenia combined with neutrophil inclusions that differ from those found in May-Hegglin syndrome or Chediak-Higashi syndrome or the Dohle bodies described in patients with sepsis. These inclusions are, however, similar to those described in Fechtner syndrome. Other features of Alport syndrome, though, including deafness, cataracts, and nephritis, are absent in Sebastian platelet syndrome. Epstein syndrome is characterized by macrothrombocytopenia without neutrophil inclusions, in addition to the classical Alport manifestations-deafness, cataracts, and nephritis-and it is also inherited in an autosomal-dominant mode. We mapped the disease-causing gene to the long arm of chromosome 22 in an Italian family with Fechtner syndrome, 2 German families with the Sebastian platelet syndrome, and an American family with the Epstein syndrome. Four markers on chromosome 22q yielded an LOD score greater than 2.76. A maximal 2-point LOD score of 3.41 was obtained with the marker D22S683 at a recombination fraction of 0.00. Recombination analysis placed the disease-causing gene in a 3.37-Mb interval between the markers D22S284 and D22S693. The disease-causing gene interval in these 3 syndromes is similar to the interval described recently in an Israeli family with a slightly different Fechtner syndrome than the one described here. Recombination analysis of these 3 syndromes refines the interval containing the disease-causing gene from 5.5 Mb to 3.37 Mb. The clinical likeness and the similar interval containing the disease-causing gene suggest that the 3 different syndromes may arise from a similar genetic defect.  相似文献   
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109.
Type III glycogen storage disease (GSD III) is an autosomal recessive disorder characterized by the accumulation of abnormal glycogen in the liver and, in most patients, in the muscle. Although liver fibrosis is a well-known consequence of GSD III, until now only eight cases of liver cirrhosis and two cases of hepatocellular carcinoma have been described in patients affected by this disease. In this case report, the authors describe the clinical history of a patient affected by GSD III who developed severe liver disease during her adult life, progressing from fibrosis to cirrhosis and finally to hepatocellular carcinoma. Until now, the hepatic involvement in GSD III has been considered by most authors as mild and almost always self-limiting. This report, together with the previously published cases, clearly indicates that severe and progressive liver disease may complicate this metabolic disorder. These observations advise a careful hepatologic follow-up of patients affected by GSD III.  相似文献   
110.
Myeloproliferative neoplasms (MPNs) and myelodisplastic syndromes (MDs) are clonal disorders caused by mutations of myeloid stem cells. Among MPNs, polycythemia vera and essential thrombocythemia are relatively benign disorders in which arterial and venous thromboses represent the main cause of morbidity and mortality. The natural history of MDs is often complicated by both thromboses and haemorrhages, mainly due to platelet quantitative and quantitative anomalies, as well as to treatment complications. In this short review, we focus the attention on the main aspects of thrombophilia in both disorders.  相似文献   
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