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排序方式: 共有850条查询结果,搜索用时 31 毫秒
21.
Edoardo Giannini Paola Ceppa Federica Botta Alberto Fasoli Paola Romagnoli Elena Cresta Valentina Venturino Domenico Risso Guido Celie Roberto Testa 《Liver international》1999,19(5):432-437
Abstract: Background/Aims: Hepatitis C virus (HCV) related disease follows a long, benign course and most affected patients have mild disease. Liver biopsy is mandatory to grade and stage the disease. Characteristic, though non-specific, HCV histological lesions such as bile duct damage and steatosis have been singled out but their association with non-histological parameters has not been completely defined. Our aim was to study the relationships among these histological lesions and clinical, biochemical, functional and virological characteristics in a group of Northern Italian patients with chronic hepatitis. Methods: We studied 172 patients with HCV-related chronic hepatitis. Patients were divided into groups on the basis of histology including bile duct damage and steatosis. Clinical, biochemical, functional and virological profiles were related to histological findings. Results: Histological grading and staging of disease increased as the age of patients increased. Steatosis was present in 70% of our patients and was related to a higher degree of fibrosis and to decreased functional activity. The prevalence of bile duct damage was 20%. This lesion was present in older patients with higher staging and impaired liver function. Biochemically it was associated with an increase in aspartate aminotransferase, gammaglutamyltranspeptidase, alkaline phosphatase, and total bilirubin. Conclusions: In the population we studied, HCV chronic hepatitis was predominantly a mild disease. Moreover both steatosis and bile duct damage were also mild. Steatosis was associated with fibrosis and this might influence liver metabolic function. Bile duct lesions were found in older patients with advanced disease showing biochemical evidence of cholestasis. The molecular role HCV might play in the pathogenesis of these histological features should be addressed in further studies. 相似文献
22.
Sreeja L Syamala VS Syamala V Hariharan S Raveendran PB Vijayalekshmi RV Madhavan J Ankathil R 《Journal of cancer research and clinical oncology》2008,134(6):645-652
Purpose Inter individual variation in lung cancer susceptibility may be modulated in part through genetic polymorphisms in the DNA
repair genes, especially the genes involved in the Base Excision Repair (BER) and nucleotide excision repair (NER) pathway.
Two of the genetic polymorphisms, XRCC1Arg399Gln and XPD Lys751Gln have been extensively studied in the association with lung
cancer risk, although published studies have been inconclusive.
Methods In order to verify the role of the common variant alleles in the XPD gene, we have genotyped 211 lung cancer patients and
211 healthy controls using PCR-RFLP assays in a hospital based, case-control study in an Indian population. Logistic regression
models were fit to examine the relationship between the log odds of lung cancer and each covariate. Overall Survival in relation
to various genotypes and clinicopathological factors were analyzed using Kaplan Meier estimates and hazard ratios were calculated
using Cox Regression analysis.
Results The carriers of XRCC1 399 AA genotypes were at higher risk of lung cancer (OR = 2.1, 95% CI:1.224–3.669, P = 0.007) than carriers
of GG genotype. Subjects carrying 751 AC genotype were at an increased risk of carcinoma of the lung (OR = 1.8; 95% CI:1.233–2.807,
P = 0.003) than subjects with AA genotypes. Compared to the XRCC1 399 GG/ XPD 751 AA reference genotype, the combined variants,
XRCC1 399 GG/ XPD 751 AC+CC (OR = 1.9, 95% CI: 1.037–3.481), P = 0.03), XRCC1 399 GA+AA/ XPD 751 AA (OR = 1.7, 95% CI: 1.020–2.833,
P = 0.04), XRCC1 399 GA+AA/XPD 751 AC+CC (OR = 2.7, 95% CI: 1.582–4.864, P = 0.01), had significantly higher odds ratios.
Increasing numbers of either XPD or XRCC1 variant alleles were associated with shorter overall survival, the risk being significant
for the XRCC1 gene polymorphism (P = 0.01 by log-rank test). The hazard of dying was significant for the XRCC1 399 AA genotype
(HR = 3.04, 95%CI: 1.393–6.670, P = 0.005). Higher tumour stage also came out as significant predictors of patient death.
Conclusions These findings suggest that genetic polymorphisms in the DNA repair genes may modulate overall lung cancer susceptibility
and that pathological stage and XRCC1 Arg399Gln independently predicted overall survival among Indian lung cancer patients. 相似文献
23.
F. Bortolotti P. Vajro F. Balli R. Giacchino C. Crivellaro C. Barbera P. Pontisso G. Nebbia L. Zancan A. Bertolini A. Alberti 《Journal of viral hepatitis》1996,3(6):323-327
SUMMARY. Several hepatitis C virus (HCV) genotypes have been recently identified and genotype 1b has been correlated with severe liver disease and a poor response to interferon therapy. HCV infection in children is an interesting model for evaluation of the relationship between HCV genotypes and liver disease, because of its relatively short duration and the infrequent association with confounding cofactors. We have investigated HCV genotypes, using a dot-blot hybridization assay with genotype-specific probes, in 36 Italian children with chronic hepatitis C who were otherwise well and had no other underlying disease. Only four patients were symptomatic; liver histology, obtained in 3 3 patients, showed minimal hepatitis in 17 and mild chronic hepatitis in 16. Infection with HCV genotype Ib was found in 55.5% of patients, with a peak prevalence of 83% in children from southern Italy (P < 0.05 vs other regions). The remaining children were infected with HCV genotype la (16.6%), genotype 2 (11.1%). and mixed (10.9%) or undetermined (2.7%) genotypes. In one patient, HCV viraemia was never detected. There was no statistically significant correlation between genotype and age, sex, source of infection, alanine aminotransferase pattern and histological activity index. These results indicate that genotype 1b is widespread among Italian children with chronic hepatitis C, although with significant geographical variations. It is not associated with a more severe liver disease, therefore suggesting that the greater severity of liver disease recently reported in adults could reflect the cumulative effects of disease duration and of interfering cofactors. 相似文献
24.
25.
Zhan Zhang Jun-Jun Gao Yang Feng Lin-Lin Zhu Huan Yan Xu-Feng Shi 《Scandinavian journal of clinical and laboratory investigation》2018,78(3):211-218
Phenylketonuria (PKU, OMIM 261600) caused by phenylalanine hydroxylase (PAH) deficiency is an autosomal recessive disease that is characterized by abnormalities of phenylalanine metabolism. In this study, a total of 77 patients, originating from the central region of China and who were diagnosed with PAH deficiency at the third affiliated hospital of Zhengzhou University, were enrolled in this study. The 13 exons and 12 flanking introns of the PAH gene were analyzed by Sanger sequencing and next generation sequencing. The sequencing data were aligned to the hg19, PAHvdb and HGMD databases to characterize the genotypes of PKU patients, and genotype–phenotype correlations and BH4 responsiveness predictions were performed using BIOPKUdb. In total, 149 alleles were characterized among the 154 PKU alleles. These mutations were located in exons 2–13, and intron 12 of the PAH gene, with a relative frequency of ≥5%, for EX6-96A>G, p.R241C, p.R243Q, p.V399V and p.R53H. Additionally, a novel variant, p.D84G, was identified. The genotype correlated with clinical symptoms in 33.3–100% of the cases, depending on the disease severity, and BH4 responsiveness predictions show that only five patients with MHP-PKU and one patient with Mild-PKU were predicted to be BH4 responsive. In conclusion, we have characterized the mutational spectrum of PAH in the central region of China and have identified a novel mutation. The hotspot mutation information might be useful for screening, diagnosis and treatment of PKU. 相似文献
26.
George M. Varghese Jeshina Janardhanan Sanjay K. Mahajan David Tariang Paul Trowbridge John A.J. Prakash Thambu David Sowmya Sathendra O.C. Abraham 《Emerging infectious diseases》2015,21(1):64-69
Scrub typhus, an acute febrile illness that is widespread in the Asia-Pacific region, is caused by the bacterium Orientia tsutsugamushi, which displays high levels of antigenic variation. We conducted an investigation to identify the circulating genotypes of O. tsutsugamushi in 3 scrub typhus–endemic geographic regions of India: South India, Northern India, and Northeast India. Eschar samples collected during September 2010–August 2012 from patients with scrub typhus were subjected to 56-kDa type-specific PCR and sequencing to identify their genotypes. Kato-like strains predominated (61.5%), especially in the South and Northeast, followed by Karp-like strains (27.7%) and Gilliam and Ikeda strains (2.3% each). Neimeng-65 genotype strains were also observed in the Northeast. Clarifying the genotypic diversity of O. tsutsugamushi in India enhances knowledge of the regional diversity among circulating strains and provides potential resources for future region-specific diagnostic studies and vaccine development. 相似文献
27.
Alexander Malogolovkin Galina Burmakina Ilya Titov Alexey Sereda Andrey Gogin Elena Baryshnikova Denis Kolbasov 《Emerging infectious diseases》2015,21(2):312-315
African swine fever virus (ASFV) causes highly lethal hemorrhagic disease among pigs, and ASFV’s extreme antigenic diversity hinders vaccine development. We show that p72 ASFV phylogenetic analysis does not accurately define ASFV hemadsorption inhibition assay serogroups. Thus, conventional ASFV genotyping cannot discriminate between viruses of different virulence or predict efficacy of a specific ASFV vaccine. 相似文献
28.
Summary
A search for the simultaneous presence of two hepatitis C virus (HCV) types in sera of a group of chronically infected intravenous
drug users, hemodialysis patients and hemophiliacs from Sweden and Russia was performed with two genotyping methods based
on the use of type-specific primers from core and NS4 regions of the viral genome. An important feature of NS4 based assay
is that type-specific primers are used in both rounds of nested PCR, thus providing the possibility of the identification
not only of the abundant type, but also of the minor HCV type present in a particular serum. The experiments, however, did
not reveal the simultaneous presence of two or more HCV types in any of the 40 samples. These results suggest that the frequency
of mixed infections in serum with different HCV types is very low even in high-risk groups, at least in the geographic region
studied.
Received: January 3, 1999 · Accepted: July 20, 1999 相似文献
29.
Hepatitis C virus (HCV) genotypes, multiple genotypes infection and HCV seroprevalence were investigated among 98 thalassemia patients and 76 haemophiliacs in Markazi province, Iran. HCV antibody was detected in 5 (5.1%) of the first group and 33 (43.4%) of the latter. Risk factors associated with anti-HCV antibody were also determined. Anti-HCV positivity in thalassemiacs were related to the number of blood transfusion units, splenectomy and duration of thalassemia. Analysis of risk factors in haemophiliacs revealed that seropositivity was significantly associated with duration of transfusion (P =0.009) and severity of disease (P = 0.000). The prevalence of HCV antibody in thalassemia subjects dropped from 8.1% to 0% after implementation of anti-HCV screening (1996). It was found that higher prevalence of HCV antibody in haemophiliacs (43.4%) compared with thalassemia patients (5.1%) correlated with clotting factor concentrates. Of the 34 seropositive haemophilia patients, HCV RNA was detected in 23 (67.7%). HCV genotype distribution was one in 50%, three in 18.2%, two in 4.54% and mixed in 27.3% (1 + 2 in 9.1%, 1 + 3 in 4.54%, 1 + 4 in 9.2% and 2 + 3a in 4.54%) cases. Among the five anti-HCV-positive thalassemiacs, two (40%) were positive for HCV RNA and one sample was found to be subtype 3a. This study confirms that multitransfused patients in Markazi province had similar genotype distribution as those previously reported form some other regions of Iran. Considering the possibilities of HCV mixed genotype among patients with haemophilia and thalassemia, accuracy and precision should be highly concerned in the detection of genotypes and their subsequent treatment. 相似文献