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Forty subjects with chronic hepatitis B and hepatitis B e antigen (HBeAg) seroconversion following lamivudine therapy in previous trials were monitored after treatment to assess the durability of serologic responses. Patient follow-up began a median of 4.3 months after completion of therapy in previous trials. At months 2, 4, 6, 9, and 12 of year 1, and every 6 months thereafter, we tested for HBeAg and hepatitis B surface antigen (HBsAg), hepatitis B virus (HBV) DNA, and alanine aminotransferase (ALT). After a median (range) of 36.6 (4.8-45.6) months of follow-up monitoring, HBeAg seroconversion was demonstrated at the last visit by 77% (30 of 39) of patients. In a post hoc analysis of a slightly different population of all 65 patients with HBeAg seroconversion in previous trials, the 3-year durability of HBeAg seroconversion measured from the time immediately after discontinuing lamivudine therapy was 64%. Nine (9 of 40, 23%) patients were HBsAg negative at the last assessment. Seventy-four percent (17 of 23) of patients with baseline undetectable HBV DNA and normal ALT maintained these responses at the last visit. Eight patients (8 of 40, 20%) initiated retreatment for reappearance of HBV markers, and 7 showed biochemical and/or virologic improvement (including regained HBeAg seroconversion in 2). No safety issues of concern emerged. In conclusion, most HBeAg responses achieved during lamivudine therapy were durable, and most responders experienced prolonged clinical benefit after HBeAg seroconversion and subsequent discontinuation of lamivudine. Lamivudine retreatment for reappearance of hepatitis B markers can achieve resumption of viral suppression.  相似文献   
54.
Genomic Instability in Pituitary Adenomas   总被引:1,自引:0,他引:1  
Pituitary adenomas most commonly are identified as small, incidental microadenomas. They however may progress to macroadenoma forming intra and later suprasellar tumors which in about 1/3 of cases invade surrounding structures at the time of diagnosis. Mechanism of pituitary tumorigenesis remains still elusive. Because the value of karyotyping is limited by the technical problems related to cytogenetic methods, we studied the spectrum of chromosomal imbalances associated with pituitary adenoma using comparative genomic hybridization (CGH). Copy number aberrations on all 22 autosomes were evaluated by CGH using advanced computer software. In total, fifteen patients were included in the study of 9 non-invasive, 4 invasive and two recurrent adenomas. The mean age of the patients were 48 years ranging from 36 to 68 years. Five tumors showed hormonal activity. The histogram of all 15 cases representing the DNA imbalances as an incidence curve along each chromosome showed losses particularly for chromosomes 1p, 2q, 4, 5, 6, 11q, 12q, 13q and 18q as well as overrepresentation on 9q, 16p, 17p, 19, 20q. Functioning adenomas carried more imbalances than non-functioning, specifically deletions on chromosome 4 and 18q as well as overrepresentations of chromosomes 17 and 19. Invasive adenomas carried more overrepresentations at 1p34 than non-invasive tumors. Recurrent adenomas harbored more alterations than primary tumors, particularly DNA gains. The primary data is accessible at our CGH online tumor database at http://amba.charite.de/cgh. Reviewing the existing literature on the genetics of pituitary adenoma and discussing our results in this context, we hope that our study will contribute to the knowledge of this neoplasm.  相似文献   
55.
Barrett's oesophagus and oesophageal adenocarcinoma, although increasingly common, have no known genetic cause. In this report we describe a family with a remarkable history of Barrett's oesophagus and adenocarcinoma. The index case is a 76-year-old man with adenocarcinoma arising within Barrett's oesophagus. Two of his three brothers, aged 68 and 78 years, also developed adenocarcinoma arising in Barrett's oesophagus and the remaining 67-year-old brother has severe dysplasia in biopsies from Barrett's oesophagus. The sons and daughters of the index case requested screening and all had histologically confirmed short-segment Barrett's oesophagus. This kindred appears to be genetically susceptible to Barrett's oesophagus and oesophageal adenocarcinoma. Pooling of data from this and other Barrett's families may allow successful linkage analysis.  相似文献   
56.
BackgroundThe aim of the study was to check the stability of a diagnosis of major depressive disorder (MDD) in an outpatient setting, as well as to assess the scope of diagnostic conversions into bipolar disorder (BD).Methods: Retrospective chart review of 122 patients with a primary diagnosis of MDD.ResultsDiagnostic conversion from MDD into BD was noticed in 40 subjects (32.8%), 25 patients (20.5%) were treatment-resistant. Mean time to the conversion was 9.27±8.64 years. A negative correlation between the age of illness onset and time to diagnostic conversion was observed (?0.41; p<0.05). Earlier onset of MDD was associated with higher risk of diagnostic conversion (<30vs≥30 years of age at onset: 69% vs 28%, p=0.0001; <35vs≥35 years of age: 50% vs 25%, p=0.0065). Treatment-resistance was more prevalent in the BD conversion group (40% vs 11%; p=0.0002). Diagnostic conversion into BD was also related longer duration of treatment received, higher number of illness episodes, and higher number of hospitalizations.Limitations: Retrospective design of the study.ConclusionsThe problem of diagnosis evolution from MDD to BD was observed in about 1/3 of patients, and was associated with treatment-resistance of depression, earlier onset of depression, longer time of treatment, higher number of depressive episodes and hospitalizations. The variables above may be a useful predictor of bipolar diathesis.  相似文献   
57.
Interleukin-6 (IL-6) may play an important role in the pathogenesis of Graves' ophthalmopathy (GO). The aim of this study was to analyze the association of IL-6 gene promoter polymorphism, at position -174 (G→C, termed as G-174C), which may affect IL-6 production, with the development of GO. The G-174C polymorphism was determined in 279 Polish-Caucasian patients with Graves' disease (GD), of which 108 had clinically evident ophthalmopathy (NOSPECS class III or higher) and 186 healthy Polish adults. In patients with GD, the frequencies of the C allele (45 vs 42%; P=0.35) and C/C genotype (20 vs 15%; P=0.13) were not significantly different compared to controls. Subdividing patients with GD for the presence of eye disease revealed that the C allele (44 vs 45%; P=0.76) and C/C genotype (20 vs 20%; P=0.92) were equally distributed in patients with or without ophthalmopathy. There was also no association between the G-174C polymorphism and the severity of eye changes. Finally, IL-6 genotypes were not associated with laboratory findings (thyroid volume, serum IL-6 and thyroid autoantibodies levels) in patients with GD at diagnosis. Our results suggest that G-174C polymorphism of the IL-6 gene does not contribute to the development and severity of GO.  相似文献   
58.
Hairy cell leukemia (HCL) is a rare, chronic lymphoproliferative disorder. Currently, purine nucleoside analogs (PNA) constitute the first line treatment of HCL. Cladribine could induce long lasting remission in majority of patients with only a single cycle of therapy. In fact the relapsed patients could be treated successfully with cladribine too. Sometimes we observe the resistance to PNA. Rituximab and chemoimmunotherapy (rituximab plus cladribine) are effective in treatment of refractory HCL.We present a case of a 64-year-old man who was treated with rituximab after second progression of HCL. In March 2011, rituximab was given at a dose of 375 mg/m2 i.v. once a week for eight weeks, with result of achievement of PR. During the last hospitalization in March 2013 the persistence of PR was confirmed.  相似文献   
59.
Single nucleotide polymorphisms (SNPs) of adhesion and signaling genes may influence the etiopathogenesis of multiple myeloma (MM). CD38 molecule and its ligand CD31 are expressed and interact in malignant plasma cells and MM microenvironment. In this study we evaluated allele frequencies and distribution of two potentially functional CD38 SNPs, intronic rs6449182 (184C>G) and missense rs1800561 (418C>T, Arg140Trp) in 175 Caucasian patients with MM and 207 healthy blood donors. The carriers of variant G allele of the rs6449182 SNPs were found to have significantly elevated risk of MM as compared to non-carriers; odds ratio = 5.69 (95% confidence interval = 3.7–8.7), p < 0.0001. In contrast, rs1800561 SNP minor T allele was detected at very low and comparable frequencies in patients and controls groups. In conclusion, our data suggest that inherited genetic variation in CD38 gene may impact on the risk of MM development.  相似文献   
60.
The most common cause of isolated thrombocytopenia is primary immune thrombocytopenia (ITP). For patients failing initial corticosteroid-based treatment and with refractory ITP post-splenectomy, thrombopoietin receptor agonists are indicated. Two of this thrombopoiesis-stimulating agents have been approved for use in ITP – eltrombopag, formulated for oral administration, once a day and romiplostim, which is administered weekly as a subcutaneous injection.  相似文献   
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