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991.
J A Chirinos Vega R Mu?oz Gómez M Amo Peláez C Ibarrola de Andrés J A Solís Herruzo 《Revista española de enfermedades digestivas》2008,100(2):104-107
INTRODUCTION: liver cirrhosis is the main cause of portal thrombosis (PT), while hypercoagulability syndromes are rarely found as the etiology of PT. We report a case of portal and mesenteric thrombosis secondary to protein S deficiency. CASE REPORT: a 74-year-old woman was admitted with melena secondary to upper gastrointestinal bleeding. She reported mild, diffuse abdominal pain in the last 2 weeks. Endoscopy revealed ruptured esophageal varices. Doppler ultrasonography and CT demonstrated a heterogeneous liver, splenomegaly and ascites, and complete non-occlusive PT involving the hilum and portal branches, as well as the superior mesenteric vein, with portosystemic collaterals. At this point a complete study for cirrhosis etiologies was negative, including a liver biopsy that showed nonspecific architectural changes secondary to diminished blood flow, which suggested non-cirrhotic portal hypertension. The search for hypercoagulability states determined a deficiency of S protein, with total pS = 107% and free pS = 56%. The patient was started on anticoagulant treatment and no other thrombotic events occurred. DISCUSSION: PT usually manifests without specific symptoms. The most common presentation is upper gastrointestinal bleeding, as occurred in our patient. Liver cirrhosis is one of the most frequent cause of PT. Up to 65% of these patients present an associated prothrombotic state, including protein S deficiency. Our case reminds us of the importance of a systematic search for hipercoagulability syndromes in patients with TP, even when the etiology can be conferred to liver cirrhosis. 相似文献
992.
Muscelli E Mingrone G Camastra S Manco M Pereira JA Pareja JC Ferrannini E 《The American journal of medicine》2005,118(1):51-57
PURPOSE: To compare the effects of equivalent weight loss induced by two bariatric surgical techniques on insulin action in severely obese patients. METHODS: Eighteen nondiabetic patients with severe obesity (mean [+/- SD] body mass index: 53.5 +/- 9.0 kg/m(2)) and 20 sex- and age-matched lean subjects (body mass index: 23.8 +/- 3.0 kg/m(2)) underwent metabolic studies, including measurement of insulin sensitivity by the insulin clamp technique. Patients then underwent either vertical banded gastroplasty with Roux-en-Y gastric bypass, or biliopancreatic diversion, and were restudied at 5 to 6 months and again at 16 to 24 months postsurgery. RESULTS: At baseline, patients were hyperinsulinemic (194 +/- 47 pmol/L vs. 55 +/- 25 pmol/L, P < 0.0001), hypertriglyceridemic (1.56 +/- 0.30 mmol/L vs. 0.78 +/- 0.32 mmol/L, P < 0.0001), and profoundly insulin resistant (insulin-mediated glucose disposal: 20.8 +/- 4.4 micromol/min/kg fat-free mass vs. 52.0 +/- 10.1 micromol/min/kg, P < 0.0001) as compared with controls. Weight loss by the two procedures was equivalent in both amount (averaging -53 kg) and time course. In the gastric bypass group, insulin sensitivity improved (23.8 +/- 6.0 micromol/min/kg at 5 months and 33.7 +/- 11.3 micromol/min/kg at 16 months, P < 0.01 vs. baseline and controls). In contrast, in the biliopancreatic diversion group, insulin sensitivity was normalized already at 6 months (52.5 +/- 12.4 micromol/min/kg, P = 0.72 vs. controls) and increased further at 24 months (68.7 +/- 9.5 micromol/min/kg, P < 0.01 vs. controls) despite a persistent obese phenotype (body mass index: 33.2 +/- 8.0 kg/m(2)). CONCLUSION: In surgically treated obese patients, insulin sensitivity improves in proportion to weight loss with use of predominantly restrictive procedures (gastric bypass), but is reversed completely by predominantly malabsorptive approaches (biliopancreatic diversion) long before normalization of body weight. Selective nutrient absorption and gut hormones may interact with one another in the genesis of the metabolic abnormalities of obesity. 相似文献
993.
Flechtner I Vaxillaire M Cavé H Scharfmann R Froguel P Polak M 《Best Practice & Research: Clinical Endocrinology & Metabolism》2008,22(1):17-40
Transient and permanent neonatal diabetes mellitus (TNDM and PNDM) are rare conditions occurring in around 1 per 300,000 live births. In TNDM, growth-retarded infants develop diabetes in the first few weeks of life, only to go into remission after a few months with possible relapse to permanent diabetes usually around adolescence or in adulthood. In PNDM, insulin secretory failure occurs in the late fetal or early postnatal period. The very recently elucidated mutations in KCNJ11 and ABCC8 genes, encoding the Kir6.2 and SUR1 subunits of the pancreatic K(ATP) channel involved in regulation of insulin secretion, account for a third to a half of the PNDM cases. Molecular analysis of chromosome 6 anomalies and the KCNJ11 and ABCC8 genes encoding Kir6.2 and SUR1 provides a tool for distinguishing transient from permanent neonatal diabetes mellitus in the neonatal period. Some patients (those with mutations in KCNJ11 and ABCC8) may be transferred from insulin therapy to sulphonylureas. 相似文献
994.
Antibiotic-resistant soil bacteria in transgenic plant fields 总被引:1,自引:0,他引:1
Demanèche S Sanguin H Poté J Navarro E Bernillon D Mavingui P Wildi W Vogel TM Simonet P 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(10):3957-3962
Understanding the prevalence and polymorphism of antibiotic resistance genes in soil bacteria and their potential to be transferred horizontally is required to evaluate the likelihood and ecological (and possibly clinical) consequences of the transfer of these genes from transgenic plants to soil bacteria. In this study, we combined culture-dependent and -independent approaches to study the prevalence and diversity of bla genes in soil bacteria and the potential impact that a 10-successive-year culture of the transgenic Bt176 corn, which has a blaTEM marker gene, could have had on the soil bacterial community. The bla gene encoding resistance to ampicillin belongs to the beta-lactam antibiotic family, which is widely used in medicine but is readily compromised by bacterial antibiotic resistance. Our results indicate that soil bacteria are naturally resistant to a broad spectrum of beta-lactam antibiotics, including the third cephalosporin generation, which has a slightly stronger discriminating effect on soil isolates than other cephalosporins. These high resistance levels for a wide range of antibiotics are partly due to the polymorphism of bla genes, which occur frequently among soil bacteria. The blaTEM116 gene of the transgenic corn Bt176 investigated here is among those frequently found, thus reducing any risk of introducing a new bacterial resistance trait from the transgenic material. In addition, no significant differences were observed in bacterial antibiotic-resistance levels between transgenic and nontransgenic corn fields, although the bacterial populations were different. 相似文献
995.
Andreas W. Schoenenberger André Moser Dominic Bertschi Peter Wenaweser Stephan Windecker Thierry Carrel Andreas E. Stuck Stefan Stortecky 《JACC: Cardiovascular Interventions》2018,11(4):395-403
Objectives
This study sought to evaluate whether frailty improves mortality prediction in combination with the conventional scores.Background
European System for Cardiac Operative Risk Evaluation (EuroSCORE) or Society of Thoracic Surgeons (STS) score have not been evaluated in combined models with frailty for mortality prediction after transcatheter aortic valve replacement (TAVR).Methods
This prospective cohort comprised 330 consecutive TAVR patients ≥70 years of age. Conventional scores and a frailty index (based on assessment of cognition, mobility, nutrition, and activities of daily living) were evaluated to predict 1-year all-cause mortality using Cox proportional hazards regression (providing hazard ratios [HRs] with confidence intervals [CIs]) and measures of test performance (providing likelihood ratio [LR] chi-square test statistic and C-statistic [CS]).Results
All risk scores were predictive of the outcome (EuroSCORE, HR: 1.90 [95% CI: 1.45 to 2.48], LR chi-square test statistic 19.29, C-statistic 0.67; STS score, HR: 1.51 [95% CI: 1.21 to 1.88], LR chi-square test statistic 11.05, C-statistic 0.64; frailty index, HR: 3.29 [95% CI: 1.98 to 5.47], LR chi-square test statistic 22.28, C-statistic 0.66). A combination of the frailty index with either EuroSCORE (LR chi-square test statistic 38.27, C-statistic 0.72) or STS score (LR chi-square test statistic 28.71, C-statistic 0.68) improved mortality prediction. The frailty index accounted for 58.2% and 77.6% of the predictive information in the combined model with EuroSCORE and STS score, respectively. Net reclassification improvement and integrated discrimination improvement confirmed that the added frailty index improved risk prediction.Conclusions
This is the first study showing that the assessment of frailty significantly enhances prediction of 1-year mortality after TAVR in combined risk models with conventional risk scores and relevantly contributes to this improvement. 相似文献996.
Major developments have occurred in the field of hematopoietic stem cell transplantation since the first successful transplants from HLA-identical siblings in the late 60's. The formally experimental procedure has become established therapy for a number of congenital or acquired disorders of the hematopoietic system and for chemotherapy-sensitive malignancies. Reduced transplant-related mortality has led to a widening of indications. The present review summarizes current issues and future prospects in allogeneic stem cell transplantation. These issues and prospects will include; stem cell sources, alternative donors, graft-versus-host disease, indications and long-term survival following allogeneic stem cell transplantation. 相似文献
997.
Resino S Galán I Pérez A Ramos JT Bellón JM Fontelos PM de José MI Gutiérrez MD Cabrero E Muñoz-Fernández MA 《AIDS research and human retroviruses》2005,21(5):398-406
We evaluated the effect of salvage antiretroviral therapy with lopinavir/ritonavir (LPV/r) on the immune system of heavily antiretroviral pretreated HIV-infected children. We carried out a longitudinal study in 20 antiretroviral experienced HIV-infected children to determine the changes in several immunological parameters (T cell subsets, thymic function) every 3 months during 18 months of follow-up on salvage therapy with LPV/r. Statistical analyses were performed with the Wilcoxon test, taking as a reference the basal value at the entry in the study. HIV-infected children showed an increase of CD4+ T cells, a decrease in CD8+ T cells, and an increase in T cell rearrangement excision circle (TRECs) levels. The percentage of HIV children with undetectable viral load (VL < or = 400 copies/ml) increased significantly (p = 0.007) and the percentage with SI viral phenotype decreased significantly (p = 0.002) at the end of the study. Thus, the viral phenotype changed to NSI/R5 after salvage therapy with LPV/r. Interestingly, we observed a significant decrease of memory (CD4+ CD45RO+) and a moderate decrease of activated (CD4+ HLA-DR+, CD4+ HLA-DR+CD38, CD4+, CD45RO+HLA-DR+) CD4+ T cells during the follow-up. On the other hand, memory (CD8+ CD45RO+ and CD8+ CD45RO+CD38+), activated (CD8+ HLA-DR+CD38+, CD8+ HLA-DR+, CD8+ CD38+), and effector (CD8+ CD57+, CD8+ CD28(-)CD57+) CD8+ T cells had a very significant decrease during follow-up. Our data indicate an immune system reconstitution in heavily pretreated HIV-infected children in response to salvage therapy with LPV/r as a consequence of a decrease in immune system activation and an increase in thymic function. 相似文献
998.
Portilla J Boix V Garcia-Henarejos JA Llopis C Martínez-Madrid O Gimeno A Sánchez-Paya J Merino E 《International journal of STD & AIDS》2005,16(12):807-810
To analyse if a four-drug combination including two protease inhibitors (PIs) accelerates viral decay and suppression as compared with standard triple therapy in heavily immunosuppressed HIV-1 infected patients, an open label clinical trial was designed. PIs naive patients receiving their first highly active antiretroviral therapy were included if their CD4 cell count was lower than 200/mm3 and their HIV viral load (VL) >100,000 RNA copies/mL. Every patient received two analogues and was randomized in two groups receiving either one PI (saquinavir soft gel capsule) or two PIs (saquinavir + nelfinavir). Viral efficacy (VL <50), time to reach VL <50, viral clearance rate constant and plasmatic elimination half-life were determined. In all, 30 patients were enrolled. No viral variable was significatively improved by the four-drug combination in the short term. No clinical benefit should be expected with a four-drug (two PIs) regimen in patients with low CD4+ cell count and high VL. 相似文献
999.
Serrano D Carrión R Balsalobre P Miralles P Berenguer J Buño I Gómez-Pineda A Ribera JM Conde E Díez-Martín JL;Spanish Cooperative Groups GELTAMO GESIDA 《Experimental hematology》2005,33(4):487-494
OBJECTIVE: To evaluate feasibility, safety, and efficacy of peripheral blood stem cell collection (PBSCC) and autologous stem cell transplantation (ASCT), to treat patients diagnosed of high-risk or relapsed HIV-associated lymphoma (HIV+ Ly), responding to highly active antiretroviral therapy (HAART). METHODS: Prospective and multicentric study in patients with high-risk or relapsed chemosensitive HIV+ Ly, candidate for consolidation with ASCT. Eligibility criteria were similar to those of HIV- lymphoma. HAART was aimed to be maintained during the procedure. RESULTS: Fourteen patients were admitted. Adequate PBSCC was obtained from all patients (median CD34+ cells was 4.7 x 10(6)/kg). Three patients died before ASCT; two had disease progression and one died from VHC-liver failure. Eleven transplanted patients showed neutrophil engraftment after a median time of 16 days (range, 9-33 days), and nine patients showed platelet engraftment after a median time of 20 days (range, 11-36 days). CD4+ cell counts and HIV viral load (VL) were appropriately preserved along the procedure. No patients died from treatment-related complications. One patient died from lymphoma progression (day +19), and another died in complete remission (CR) with undetectable VL, 15 months after transplant, due to infection. One patient relapsed at 32 months after ASCT. The remaining eight patients are alive in CR with an event-free survival of 65% and a median follow-up of 30 months after ASCT (range, 7-36 months). CONCLUSIONS: These results show that feasibility, safety, and efficacy of PBSCC and ASCT in HIV+ Ly patients responding to HAART are similar to those observed in the HIV- lymphoma setting. 相似文献
1000.
Treatment of portal hypertension 总被引:1,自引:0,他引:1