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71.
To determine whether the clinical and immunological expression of patients with cryoglobulinaemia associated with chronic hepatitis C virus (HCV) infection varied according to HCV-RNA load, HCV genotype or human immunodeficiency virus (HIV) coinfection. We studied 340 HCV patients (188 women and 152 men, with a mean age of 49 years) consecutively diagnosed with cryoglobulinaemia between 1993 and 2003 in our hospital. HCV infection was confirmed by serum HCV-RNA determination in all patients. Two hundred and forty-eight (73%) patients had asymptomatic cryoglobulinaemia and 92 (27%) presented cryoglobulinaemic symptoms. Patients with genotype 1 had a higher mean age at diagnosis of cryoglobulinaemia (48.2 vs 40.2 yrs, P < 0.001) and a higher prevalence of cryoglobulinaemic symptoms (25%vs 10%, P = 0.02), especially of vasculitic features (19%vs 5%, P = 0.014). In comparison with monoinfected HCV patients, those with HIV coinfection had a lower mean age at diagnosis of cryoglobulinaemia (40.4 vs 52.8 years, P < 0.001), a lower prevalence of cryoglobulinaemic symptoms (15%vs 34%, P < 0.001), vasculitis (10%vs 28%, P < 0.001), associated systemic autoimmune disease (3%vs 14%, P = 0.001), rheumatoid factor (30%vs 70%, P = 0.001) and hypocomplementaemia (50%vs 78%, P = 0.01). In HCV-HIV patients, a high viral load was associated with a high frequency of symptomatic cryoglobulinaemia, especially in patients with a high viral load of the two viruses (50%vs 7%, P = 0.001) A higher frequency of cryoglobulinaemic symptoms (especially vasculitis) was found in patients with HCV monoinfection and in those carrying HCV genotype 1. In contrast, patients with HIV coinfection presented a threefold lower prevalence of vasculitis. Associated HIV infection significantly attenuated the clinical and immunological expression of cryoglobulinaemia, except in coinfected patients with high viral loads for the two viruses.  相似文献   
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73.
In order to identify the main routes of hepatitis C (HCV) transmission and to determine the HCV genotype distribution and its dynamics during a 15‐year period in Slovenia, HCV genotypes were detected using the INNO‐LiPA HCV II (Innogenetics) test for serum samples obtained from 1,504 patients representing 72.6% of all patients with chronic hepatitis C diagnosed from 1993 to 2007. HCV genotype 1 was predominant (56%), followed by genotypes 3, 2, and 4, with a prevalence of 37.8%, 5%, and 1.2%, respectively. HCV genotypes 5 and 6 were not detected in any patient. Patients infected with HCV genotype 3 were significantly younger (mean age 28.9 ± 8.5 years) than those infected with genotype 1 (mean age 38.9 ± 14.8 years; P < 0.0001) and those infected with HCV genotype 2 (mean age 50.3 ± 18.2 years; P < 0.0001). Intravenous drug use was identified as the most frequent possible HCV transmission route (34.3%), followed by medical‐related transmission such as transfusion of HCV‐contaminated blood or blood products, and hemodialysis (12.5%). Being an intravenous drug user was found to be strongly associated with HCV genotype 3 (OR, 3.71 [95% CI, 2.97–4.65]; P < 0.0001) and reporting infection by transfusion of blood or blood products was found to be strongly associated with HCV genotype 1 (OR, 3.28 [95% CI, 2.18–4.95]; P < 0.0001). During the 15‐year period, the proportion of genotype 3 increased substantially, reflecting the fact that the HCV epidemic in Slovenia is driven mostly by intravenous drug use. J. Med. Virol. 81:634–639, 2009 © 2009 Wiley‐Liss, Inc.  相似文献   
74.
The aim of this survey was to assess the prevalence and distribution of oncogenic human papillomavirus (HPV) genotypes in women who underwent screening for cervical cancer in Italy. The correlation of genotypes with the cytological results was also evaluated. Cervical samples were collected from 9,947 self‐referring women for cervical cancer screening. Participants were screened by liquid‐based cytology and high‐risk HPV testing using the Hybrid Capture 2 test. Positive samples were genotyped by PCR. Samples (1,474; 14.8%) were positive for high‐risk HPV. The prevalence was 29.4% in the 15–19 years‐group, decreasing progressively to 6.1% at 50–54 years of age and increasing to 12.2% in those aged over 65 years. HPV 16 was the genotype detected most frequently followed by HPV 31, HPV 18, HPV 56, and HPV 51. HPV 16 or 18 were present in 4% of women with normal cytology and both were detected contemporarily in only 14 women. Twenty‐two percent of atypical squamous cells, 26% of low‐grade and 56% of high‐grade squamous intraepithelial lesions at cytology were positive for HPV 16 and/or 18. The prevalence of HPV infection in Italy is in agreement with that reported worldwide. HPV 16 was the prevalent genotype. The concomitant infection with HPV 16 and HPV 18 (vaccine targets) was found rarely. Apart from HPV 16 and 18, there was a substantial presence of HPV genotypes against which the vaccines available currently have shown cross‐protection efficacy. The findings of this study may contribute to reliable predictions on the potential efficacy of an HPV vaccine in clinical practice. J. Med. Virol. 81:529–535, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
75.
The distribution of hepatitis C virus (HCV) genotypes was evaluated in individuals with hepatocellular carcinoma (HCC) and cirrhosis in Egypt. A total of 206 patients sero‐positive for HCV‐RNA among 400 surveyed individuals (186 with HCC, 100 with cirrhosis, and 114 healthy volunteers) were analyzed for HCV genotype. Of 206 patients, 129 had HCC, 65 had cirrhosis without HCC, and 12 were healthy volunteers. Phylogenetic analysis of sequence showed that of 206 samples, 186 contained HCV genotype 4 (90.3%), while 20 had HCV genotype 1 (9.7%). Among subjects with genotype 4, subtype 4a was predominant (79%), other subtypes included 4d, 4m, 4n, and 4o. Among those with HCV genotype 1, 15 had subtype 1g and five subtype 1a. Although subtype 4a was noted slightly more frequently in HCC (76%) compared to cirrhosis (66%) and controls (50%), there was no statistically significant difference between these three groups (P = 0.08). In conclusion, HCV genotype 4 predominates in Egypt. There was no association between subtypes of genotype 4 and the development of HCC. J. Med. Virol. 81:844–847, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
76.
目的:探讨人乳头瘤病毒(HPV)各亚型在广西沿海地区宫颈癌患者中的分布情况,HPV感染与宫颈癌患者的年龄、临床分期、病理类型、分化程度、肿瘤盆腔淋巴结转移及肿瘤的复发的关系。方法:通过凯普导流杂交HPV DNA检测法,对76例宫颈癌患者宫颈脱落细胞进行21种HPV亚型的检测。结果:宫颈癌HPV总阳性率为90.8%。宫颈癌患者HPV阳性各亚型出现的频率排序为:HPV16(56.5%),HPV18、33、58各(7.2%),HPV52、53各(5.8%),HPV31(4.3%),HPV45(2.9%),HPV35、51、56、66、68各(1.4%)。HPV6(5.8%),HPV11、44、43各(1.4%)均合并在高危感染中。HPV感染与临床分期、肿瘤分化程度、肿瘤盆腔淋巴结转移及肿瘤的复发关联无显著性(P>0.05),与年龄密切相关,鳞癌HPV阳性率明显高于腺癌及其它癌,差异有统计学意义(P<0.05)。结论:广西沿海地区妇女宫颈癌患者中以HPV16、18、33、58感染为主要型别。HPV感染与宫颈癌的临床分期、肿瘤分化程度、肿瘤盆腔淋巴结转移及肿瘤的复发无明显相关性,与发病年龄、病理类型有关。  相似文献   
77.
78.
Two millilitres of peripheral blood was collected from 323 patients of different age groups and rapid diagnosis (RDT test) was performed. Parasite genomic DNA was extracted from whole blood and MSP-2 gene-based diversity and polymorphism was determined followed by restriction fragment length polymorphism analysis using Taq1 and Vsp1 digestion of each polymerase chain reaction product to analyse MSP-2 genotypes. Twenty-six sequences of P. falciparum MSP-2 gene were retrieved from the current GenBank database to represent strains from various geographical locations and were analysed for the Taq1 and Vsp1 enzyme restriction sites using in silico restriction digestion in Sequence Manipulation Suite, Version 2.  相似文献   
79.
The bovine respiratory syncytial virus (BRSV) is an enveloped, negative sense, single-stranded RNA virus belonging to the pneumovirus genus within the family Paramyxoviridae. BRSV has been recognized as a major cause of respiratory disease in young calves since the early 1970s. The analysis of BRSV infection was originally hampered by its characteristic lability and poor growth in vitro. However, the advent of numerous immunological and molecular methods has facilitated the study of BRSV enormously. The knowledge gained from these studies has also provided the opportunity to develop safe, stable, attenuated virus vaccine candidates. Nonetheless, many aspects of the epidemiology, molecular epidemiology and evolution of the virus are still not fully understood. The natural course of infection is rather complex and further complicates diagnosis, treatment and the implementation of preventive measures aimed to control the disease. Therefore, understanding the mechanisms by which BRSV is able to establish infection is needed to prevent viral and disease spread. This review discusses important information regarding the epidemiology and molecular epidemiology of BRSV worldwide, and it highlights the importance of viral evolution in virus transmission.  相似文献   
80.
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