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991.
We describe the characterization of a novel 7.9 kb deletion that eliminated one of the duplicated alpha-globin genes, causing an alpha+-thalassaemia phenotype in two independent carriers of Suriname-Indian origin. The molecular characterization of the deletion breakpoint fragment revealed neither involvement of Alu repeat sequences nor the presence of homologous regions prone to recombination, suggesting a non-homologous recombination event. This alpha+-thalassaemia deletion was found to give rise to an atypical haemoglobin H (HbH) disease characterized by a non-transfusion-dependent moderate microcytic hypochromic anaemia in combination with a poly adenylation signal mutation of the alpha-globin gene (alpha2 AATAAA --> AATA-- --).  相似文献   
992.
A comparison of fibrosis progression in chronic liver diseases   总被引:13,自引:0,他引:13  
BACKGROUND/AIMS: No study has compared the liver fibrosis progression rates among chronic liver diseases and the risk factors in order to better organize screening strategies. METHODS: A total of 4852 patients were retrospectively studied (chronic hepatitis C (HCV) [n=2313], human immunodeficiency virus (HIV)-HCV co-infection (HIV-HCV [n=180]), hepatitis B (HBV [n=777]), alcoholic liver disease (ALD [n=701]), primary biliary cirrhosis (PBC [n=406]), genetic hemochromatosis (GH [n=383]) auto-immune hepatitis (AIH [n=57]) and delta hepatitis (n=35). The fibrosis progression rates were estimated from birth and from the date of exposure, when known, to the first biopsy. RESULTS: There were highly significant differences in the rates of fibrosis progression, the most rapid being HIV-HCV co-infection (50% cirrhosis percentile at 52 years of age) and the slowest being PBC (50% cirrhosis percentile at 81 years). There was an acceleration of fibrosis progression with aging. Fibrosis progression was slower in females compared with males for HCV, HBV, GH, and PBC. In contrast, in ALD, the fibrosis progression was more rapid in females. CONCLUSIONS: Rates of fibrosis progression differ markedly between the predominant causes of chronic liver disease, and according to age and gender. Patients with HIV-HCV co-infection are at particularly high risk of fibrosis progression.  相似文献   
993.
Pregnancy and Crohn's disease   总被引:3,自引:0,他引:3  
Crohn's disease commonly affects women of childbearing age. Available data on Crohn's disease and pregnancy show that women with Crohn's disease can expect to conceive successfully, carry to term and deliver a healthy baby. Control of disease activity before conception and during pregnancy is critical, to optimize both maternal and fetal health. Generally speaking, pharmacological therapy for Crohn's disease during pregnancy is similar to pharmacological therapy for non-pregnant patients. Patients maintained in remission by way of pharmacological therapy should continue it throughout their pregnancy. Most drugs, including sulfasalazine, mesalazine, corticosteroids, and immunosuppressors such as azathioprine and 6-mercaptopurine, are safe, whereas methotrexate is contraindicated.  相似文献   
994.
Cryopyrinopathies are a group of rare autoinflammatory diseases that includes familial cold autoinflammatory syndrome, Muckle-Wells syndrome and chronic infantile neurologic cutaneous articular syndrome (also termed neonatal-onset multisystemic inflammatory disease). These syndromes were initially considered to be distinct disease entities despite some clinical similarities; however, mutations of the same gene have since been found in all three cryopyrinopathies. These diseases, therefore, are not separate but represent a continuum of subphenotypes. The gene in question, CIAS1 (now renamed NLRP3) encodes NALP3 (also known as cryopyrin). NALP3 is an important mediator of inflammation and interleukin 1beta processing. New therapies based on biologic agents that specifically target interleukin 1beta are currently being developed. These new agents have provided very encouraging results for patients with these long-lasting inflammatory conditions--which used to be considered refractory to treatment. The development of therapeutic options for these cryopyrinopathies illustrates effective translation of basic science to clinical practice and the convergence of human genetics and targeted therapies.  相似文献   
995.
The HOVON cooperative study group performed a feasibility study of escalated imatinib and intravenous cytarabine in 165 patients with early chronic-phase chronic myeloid leukemia (CML). Patients received 2 cycles of intravenous cytarabine (200 mg/m(2) or 1000 mg/m(2) days 1-7) in conjunction with imatinib (200 mg, 400 mg, 600 mg, or 800 mg), according to predefined, successive dose levels. All dose levels proved feasible. Seven dose-limiting toxicities (DLTs) were observed in 302 cycles of chemotherapy, which were caused by streptococcal bacteremia in 5 cases. Intermediate-dose cytarabine (1000 mg/m(2)) prolonged time to neutrophil recovery and platelet recovery compared with a standard dose (200 mg/m(2)). High-dose imatinib (600 mg or 800 mg) extended the time to platelet recovery compared with a standard dose (400 mg). More infectious complications common toxicity criteria (CTC) grade 3 or 4 were observed after intermediate-dose cytarabine compared with a standard-dose of cytarabine. Early response data after combination therapy included a complete cytogenetic response in 48% and a major molecular response in 30% of patients, which increased to 46% major molecular responses at 1 year, including 13% complete molecular responses. We conclude that combination therapy of escalating dosages of imatinib and cytarabine is feasible. This study was registered at www.kankerbestrijding.nl as no. CKTO-2001-03.  相似文献   
996.
BACKGROUND: Diastolic dysfunction and lack of contractile reserve are unfavorable prognostic predictors in patients with dilated cardiomyopathy (DCM). AIMS: This study aims to assess whether diastolic dysfunction and lack of dipyridamole-induced contractile reserve were additive predictors of poor outcome in patients with DCM. METHODS: A total of 116 patients with DCM and ejection fraction (EF<35%) were studied by dipyridamole echo (0.84 mg/kg over 10 min). At rest, a restrictive filling pattern was defined as: E/A ratio >2 and an E-wave deceleration time of <140 ms on transmitral flow velocity profile. RESULTS: Rest wall motion score index (WMSI) was 2.2+/-0.3 and decreased to 1.9+/-0.41 after dipyridamole (p<0.001). During follow-up (median 26.5 months), 22 cardiac deaths occurred. At multivariate analysis, dipyridamole-induced contractile reserve yielded significant incremental prognostic value (RR=0.275, p<0.006) over NYHA class (RR=1.971, p<0.03), angiotensin-converting enzyme inhibitor therapy (RR=0.173, p<0.001), and left ventricular end-diastolic diameter (RR=1.131, p<0.001). The worst prognostic combination was the presence of restrictive pattern at rest and the absence of contractile reserve (deltaWMSI<0.15). CONCLUSION: In patients with DCM, the ominous combination of restrictive transmitral flow pattern and lack of contractile reserve during dipyridamole stress predicts an unfavourable outcome.  相似文献   
997.
998.
AIMS: Fluoroscopy is not available in every endoscopic unit. This situation leads to delays in treatment or to transfer of patients to other centres for stent insertion. We assessed safety and effectiveness of expandable esophageal metal stent placement under endoscopic control without fluoroscopy using a thin gastroscope. PATIENTS AND METHODS: From October 2002 to June 2004, thirty-three consecutive patients have been included for esophageal stent placement under endoscopic control alone with a nasogastroscope (5.9 mm). A proximal release covered stent (Ultraflex; Boston Scientific Microvasive) was used. Indications were malignant esophageal stricture (N = 26), malignant extrinsic compression (N = 2 ) and esophago-respiratory neoplastic fistulae (N = 5). RESULTS: Stent placement using endoscopic control alone was successful in 30/33 (90%) patients. Complications occurred in 11 patients. Early complications (<7 days) included one death from pulmonary embolism, severe retrosternal pain needing transient morphinic treatment (N = 2) and GERD despite antisecretory therapy (N = 1). Late complications included: food impaction (N = 1), tumour overgrowth-related obstruction of the stent (N = 5) and one late esophago-respiratory fistula at 4 months at the proximal end of the stent. Relief of dysphagia was obtained for all patients at 48 hours and dysphagia score decreased from 3.1 before stent to 1.2 at 1 month (P < 0.05). CONCLUSION: Expandable esophageal stents can be accurately and safely placed using endoscopy with a thin gastrosocope. This method obviates the requirement of fluoroscopic access, lacking in many centres, and avoids exposure to X-ray.  相似文献   
999.
OBJECTIVES: We sought to determine whether direct stenting might prevent the adverse events associated with stent implantation during primary angioplasty and to compare it with conventional stent implantation in patients with acute myocardial infarction (AMI). BACKGROUND: No trial has demonstrated that stents favorably influence mortality rate. Recent studies have even suggested a negative impact of stents on coronary blood flow and clinical outcome. METHODS: Of 409 patients treated by primary angioplasty with stent implantation in our center, 206 (50%) were enrolled in this randomized, single-center trial and allocated to direct stent implantation (n = 102) or stent implantation after balloon pre-dilation (n = 104). The study end points included angiographic results (final corrected Thrombolysis In Myocardial Infarction [TIMI] frame count and a composite end point of slow and no-reflow or distal embolization), an electrocardiogram marker of myocardial reperfusion assessment (ST-segment resolution) and in-hospital clinical outcome (death and recurrent infarction). RESULTS: Direct stent implantation failed in eight patients but succeeded after pre-dilation in all. A non-significant increase in TIMI flow grade 3 was achieved after direct stenting (95.1% vs. 93.3%, p = 0.74) without significant difference in the corrected TIMI frame count (31.5 +/- 17 and 35.2 +/- 20 frames after direct and conventional stent, respectively, p = 0.42). The composite angiographic end point was significantly reduced by direct stent implantation (11.7% vs. 26.9%, p = 0.01). ST-segment resolution was also significantly improved after direct stent (no ST-segment resolution in 20.2% vs. 38.1% after direct and conventional stent, respectively, p = 0.01). Death and/or recurrent infarction occurred in six patients after conventional stent implantation and in two patients after direct stenting (p = 0.28). CONCLUSIONS: In selected patients with AMI, direct stenting can be applied safely and effectively. This strategy may result in a significant reduction of microvascular injury, as suggested by improved ST-segment resolution after reperfusion with major potential clinical consequences.  相似文献   
1000.
Given that the FcgammaRIIIa receptor 158V allotype displays a higher affinity for human immunoglobulin G1 and increased antibody-dependent cellular cytotoxicity, the aim of this study was to determine the influence of that FCGR3A polymorphism on the therapeutic response to rituximab, an anti-CD20 humanized immunoglobulin G1 increasingly used in the treatment of non-Hodgkin lymphomas. The FCGR3A-158V/F genotype was determined in 49 patients having received rituximab for a previously untreated follicular non-Hodgkin lymphoma. The clinical response and the disappearance of the BCL2-JH gene rearrangement in both peripheral blood and bone marrow were evaluated at 2 months (M2) and at 1 year (M12). The study population consisted of 20% FCGR3A-158V homozygous patients, 35% FCGR3A-158F homozygous patients, and 45% heterozygous patients (FCGR3A-158F carriers). The objective response rates at M2 and M12 were 100% and 90%, respectively, in FCGR3A-158V homozygous patients compared with 67% (P =.03) and 51% (P =.03), respectively, in FCGR3A-158F carriers. A disappearance of the BCL2-JH gene rearrangement in both peripheral blood and marrow was observed at M12 in 5 of 6 of homozygous FCGR3A-158V patients compared with 5 of 17 of FCGR3A-158F carriers (P =.03). The homozygous FCGR3A-158V genotype was confirmed to be the single parameter associated with clinical and molecular responses by multivariate analysis. This study showed an association between the FCGR3A genotype and clinical and molecular responses to rituximab. This finding will certainly give rise to new pharmacogenetic approaches to the management of patients with non-Hodgkin lymphomas.  相似文献   
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