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1.
OBJECTIVES: The factors influencing the histological severity of chronic hepatitis C (CHC) have not been well established. We therefore investigated the effect of hepatitis C virus (HCV) genotypes and human immunodeficiency virus (HIV) infection on histological liver damage in a cohort of intravenous drug users with CHC. METHODS: We analyzed the histological activity score and the HCV genotypes in 59 HCV-RNA-positive patients with biopsy-proven CHC. Forty-eight (81%) of them had concomitant HIV infection with a CD4+ cell count above 200 x 10(6) cells/L and an absence of AIDS-defining conditions. Multivariate analysis was performed to determine the features associated with the histological severity. RESULTS: Minimal/mild hepatitis was found in 16 patients (27%), moderate chronic hepatitis in 29 (49%), and severe chronic hepatitis in 14 (24%). Patients with HCV subtype 1b had a higher histological score than others (8.7 +/- 3.3 vs. 6.5 +/- 3.2, p = 0.012), either as single or mixed infections. In multivariate analysis, HIV-infected individuals had a higher score of piecemeal necrosis (OR = 21.7, p = 0.002) and a higher stage of fibrosis (OR = 17.9, p = 0.004) than patients without HIV infection. HIV infection and HCV genotype 1b were found to be independent factors of histological severity. CONCLUSIONS: Liver damage in patients with CHC seems to be directly influenced by HCV subtypes. Infection by HCV subtype 1b is closely associated with more severe forms of liver pathology. Furthermore, the presence of HIV infection is an independent factor associated with more aggressive histological damage. In these patients, higher degrees of piecemeal necrosis and fibrosis are commonly seen.  相似文献   

2.
There are no reports to date of entire gene sequences coding for chitinolytic enzymes from entomopathogenic fungi, even though these enzymes act synergistically with proteolytic enzymes to solubilize insect cuticle during the key step of host penetration, having considerable importance in the biological control of some insect pests. This paper reports the complete nucleotide sequence and analysis of the chromosomal and full-length cDNA copies of the regulated gene (chit1) coding one of the chitinases produced by the biocontrol agent Metarhizium anisopliae. Degenerated primers, encompassing conserved regions of other fungal chitinases, were used to amplify a 650-bp DNA fragment, which was used to isolate genomic and cDNA clones from M. anisopliae. Albeit at least two different chitinases are characterized in this fungus, only one chit gene was isolated. The chit1 gene is interrupted by three short typical fungal introns and has a 1,521-bp ORF, which encodes a protein of 423 amino acids with a stretch of 35 amino acid residues displaying characteristics of signal peptide. The deduced sequence of the mature protein predicts a 42-kDa protein with pI of 5.8. Southern analysis of genomic DNA indicates a single copy of chit1 in the M. anisopliae genome.  相似文献   

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BACKGROUND: After recently published own investigations on subjective and objective cyclorotatory changes following inferior oblique recession for inferior oblique overaction, it was our aim to determine and to compare subjective and objective cyclorotatory changes following a modified Harada-Ito procedure for acquired trochlear palsy. PATIENTS AND METHODS: Eight patients suffering from acquired uni-(n = 3) or bilateral (n = 5) trochlear palsy were investigated before surgery and 1 day, 3 days and 4 months after surgery. Subjective cyclodeviation was assessed by Harms' tangent scale. Objective cycloposition was measured by means of fundus cyclometry using an infrared Scanning Laser Ophthalmoscope. RESULTS: The immediate postoperative incyclorotatory effect was 12 degrees in the unilateral group and 18 degrees in the bilateral group. Subjective and objective changes were nearly equal in both groups, with a subjective over-effect of 1 degree. After two days of binocular stimulation a marked regression of the surgical effect was found which still increased after four months. The long term incyclorotatory effect was subjectively and objectively nearly equal in the unilateral group which showed a relaps of subjective excyclodeviation of 5 degrees: in the bilateral group, the subjective effect was more pronounced than the objective effect, the immediate postoperative over-effect being disappeared. CONCLUSIONS: In contrast to our results concerning inferior oblique muscle recession for strabismus sursoadductorius, subjective and objective cyclorotatory changes did not differ grossly following a modified Harada-Ito procedure. Subjective and objective short and long term regression was confirmed which objectively exceeded the amount of over-correction. As the underlying cause mechanical and sensory mechanisms are discussed.  相似文献   

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BACKGROUND/AIMS: Patients with chronic hepatitis C are often coinfected with the new identified Flaviviridae-like agent, termed hepatitis G virus (HGV). The aim of the study was to investigate the responsiveness of hepatitis G virus to interferon alpha and to evaluate whether a hepatitis G virus coinfection negatively influences the outcome of treatment in chronic hepatitis C. METHODS: One hundred and fifteen patients with histologically proven chronic hepatitis C were treated with interferon alpha and investigated for the presence of hepatitis G virus coinfection by nested polymerase chain reaction with primers from the helicase region of hepatitis G virus. All patients received at least 3 MU (range 3-6) interferon alpha thrice weekly for at least 6 months (mean 8, range 6-12). Polymerase chain reaction products of seven pre- and post-treatment hepatitis G virus positive patients were directly sequenced for identification of sequence variability during the follow-up. RESULTS: Eighteen (16%) patients were coinfected with hepatitis G virus. Although nine (50%) of these patients became HGV RNA negative during interferon alpha therapy, only three patients (17%) remained HGV RNA negative at the end of follow-up (mean 24 months). The rate of sustained response of chronic hepatitis C was not significantly different between patients with hepatitis C virus infection and HCV/HGV coinfection (19% vs 28%). Severity of liver disease as determined by alanine aminotransferase levels, histology and hepatitis C virus viremia was not significantly different in patients with hepatitis C virus or HCV/HGV coinfection. Sequence analysis of the helicase region revealed that our isolates all belonged to the hepatitis G virus and not to the GBV-C like genotype. No amino acid exchanges during the observation period of up to 48 months were observed, indicating that this region is highly conserved. CONCLUSIONS: The responsiveness of hepatitis G virus to interferon alpha in chronic HCV/HGV coinfected patients is similar to that observed in chronic hepatitis C. Hepatitis G virus coinfection seems not to interfere with the efficacy of interferon alpha treatment in patients with chronic hepatitis C.  相似文献   

7.
In patients receiving interferon therapy for chronic hepatitis C, serum hepatitis C virus (HCV) RNA often reverts from an undetectable to a detectable form after completion of treatment. Detection of the negative strand of HCV-RNA in liver tissue is regarded as an index of viral proliferation. Therefore, we investigated changes in the hepatic negative-strand HCV-RNA following interferon therapy to determine whether this parameter could predict the long-term response to treatment. The subjects of this study were 27 patients with chronic active hepatitis C. Serum positive-strand and hepatic tissue negative-strand HCV-RNA were detected using polymerase chain reaction. At the completion of interferon treatment, serum HCV-RNA was not detected in 21 patients. One year following treatment it remained undetectable in 14 of these patients but it had reverted to a detectable form in seven. The 14 patients in whom hepatic negative-strand RNA was not detected between 2 weeks and 12 months after treatment, had not relapsed after another year. In the 13 remaining patients, negative-strand RNA was found in liver tissue and serum RNA either reverted to a detectable form or remained detectable throughout. From these findings, we conclude that the detection of negative-strand HCV-RNA in liver tissue 2 weeks after the completion of interferon therapy is useful for predicting the long-term effect of therapy.  相似文献   

8.
To investigate the influence of genetic and/or environmental factors in the development and shaping of the human peripheral T cell repertoire the authors studied the T-cell receptor (TCR) V beta usage in 10 adult monozygous (Mz) and nine dizygous (Dz) twin pairs living in a Plasmodium falciparum endemic area in West Africa. The TCR repertoire was determined using a small panel of anti-V beta specific monoclonal antibodies (MoAbs) using conventional immunofluorescence assays. The results revealed that the V beta repertoire was similar to that recently described for a Caucasian population using a similar panel of antibodies. The frequencies of particular V beta genes tested were influenced neither by anti-malarial antibody titres nor by parasite densities, indicating that the P. falciparum parasite is not a dominating factor in determining the peripheral T cell repertoire. All donors were human leucocyte antigen (HLA) class I and II typed; no association was found between the expression of any V beta genes and MHC haplotype. The V beta usage was more concordant within the Mz than within the Dz pairs. For a group comprising four HLA class II identical individuals, the average within-pair difference was significantly greater than for the whole Mz group, but similar to that seen for the total Dz group. Thus, the data suggest that genetic, rather than environmental, factors have a profound effect on the shaping of the human circulating T cell repertoire and that the major genetic factors are encoded by non-HLA class II genes.  相似文献   

9.
BACKGROUND/AIMS: To study the effects of the immunosuppression caused by the reduction of CD4 activity on the composition of hepatitis C virus (HCV) populations, we analyzed the number of HCV quasispecies clones and the nucleotide diversity of the hypervariable region 1 (HVR1) of HCV in 37 patients with hemophilia with persistent HCV infection, with or without human immunodeficiency virus (HIV). METHODS: The numbers of HCV quasispecies clones were measured by fluorescence single-strand conformation polymorphism analysis. Direct sequencing was used to analyze the degree of diversity of HVR1. We compared these values according to coinfection with HIV, and CD4 counts of patients. RESULTS: There were no differences in either the number of HCV clones or the diversity between patients with and without HIV coinfection. In HIV coinfected patients the diversity decreased in association with the decrease in CD4 count while the number of HCV clones did not. The diversity of HVR1 was 3.64 +/- 5.03% in patients with a CD4 count < 50/microliters and 14.92 +/- 6.03% in patients with a CD4 count > or = 50/microliters; it was significantly lower in the former (p = 0.0002). CONCLUSIONS: A severe reduction in the CD4 count, which is considered to cause a decline in the activity of helper T-lymphocytes, induced changes in the composition of HCV populations; one or a few quasispecies clones are predominant in the HCV population in the serum of individual patients.  相似文献   

10.
To demonstrate effectiveness by relative low-dose of interferon treatment for patients with chronic hepatitis C, we investigated the histological activity index (HAI) score of liver tissue, hepatitis C virus (HCV) genotype by polymerase chain reaction (PCR) with type-specific primers, HCV RNA levels by competitive PCR, serum aminotransferase, sex, age, history of blood transfusion and history of hepatitis in patients with chronic hepatitis C prior to treatment. Twenty-two patients were treated with human lymphoblastoid interferon (3 MU daily, 2 weeks, 3 MU thrice a week, 6 weeks, 1.5 MU thrice a week, 16 weeks) for 24 weeks, of whom 10 (45.5%) were responders within a 6 month follow-up. HAI score before treatment was significantly lower in responders than in a combined group of relapse patients and nonresponders (7.5 +/- 3.4 vs. 12.0 +/- 3.1, p < 0.01). The prevalence of responders in patients with genotypes III and IV was significantly higher than in those with genotype II (85.7% vs. 21.4%, p < 0.05). HCV RNA level (logarithmic transformed copy per 50 microliter of serum) was significantly lower in responders than in a combined group of relapse patients and nonresponders (4.8 +/- 1.2 vs. 5.7 +/- 0.8, p < 0.05). In case of other pretreatment factors, there were no significant differences between responders and a combined group relapse patients and nonresponders. Thus severe histological changes in the liver, HCV genotype II and high HCV RNA levels are markers of unfavorable effects of interferon treatment for patients with chronic hepatitis C.  相似文献   

11.
Thrombocytopenia that is associated with infection due to human immunodeficiency virus (HIV) is an important and common hematologic abnormality. Although this condition is often asymptomatic, it may manifest clinically as a spectrum of bleeding problems including petechiae, ecchymoses, epistaxis, or menorrhagia or as hemorrhage of the gingivae, gastrointestinal tract, or CNS. Thrombocytopenia may be present in patients at any stage of immunodeficiency, and spontaneous remission can occur. We review the natural history of HIV-related thrombocytopenia and discuss treatment options.  相似文献   

12.
There is limited information about the long-term efficacy of prolonged therapy (more than 6 months) with interferon alpha in hemophilic patients with chronic hepatitis C who are not coinfected with the human immunodeficiency virus (HIV-1). One hundred and seven hemophiliacs were randomly assigned to 3 million U of interferon alpha2b three times weekly for 12 months or no therapy. The patients were followed up for at least 12 months posttreatment. Response was assessed by both serial alanine aminotransferase (ALT) levels and hepatitis C virus (HCV)-RNA measured by reverse transcribed polymerase chain reaction (RT-PCR) method. Before treatment, serum levels of HCV-RNA were measured quantitatively by second-generation branched-DNA assay and the HCV genotype was determined by RT-PCR. Serum HGV-RNA, a marker of infection with the hepatitis G virus, was also measured by RT-PCR. Normalization of ALT was sustained and serum HCV-RNA was cleared in 6 of 45 treated patients, compared with none of the 50 untreated controls (13% v 0% P < .01). Low pretreatment viremia was the only feature that was associated with an increased likelihood of sustained response (P < .01). This study shows that multitransfused hemophiliacs with chronic hepatitis C not coinfected with HIV-1 respond at low rates to prolonged interferon therapy.  相似文献   

13.
1. The structure activity relationships for the insulin secretagogues N-benzoyl-D-phenylalanine (NBDP) and related compounds were examined at the sulphonylurea receptor level by use of cultured HIT-T15 and mouse pancreatic beta-cells. The affinities of these compounds for the sulphonylurea receptor were compared with their potencies for K(ATP)-channel inhibition. In addition, the effects of cytosolic nucleotides on K(ATP)-channel inhibition by NBDP were investigated. 2. NBDP displayed a dissociation constant for binding to the sulphonylurea receptor (K(D) value) of 11 microM and half-maximally effective concentrations of K(ATP)-channel inhibition (EC50 values) between 2 and 4 microM (in the absence of cytosolic nucleotides or presence of 0.1 mM GDP or 1 mM ADP). 3. In the absence of cytosolic nucleotides or presence of GDP (0.1 mM) maximally effective concentrations of NBDP (0.1-1 mM) reduced K(ATP)-channel activity to 47% and 44% of control, respectively. In the presence of ADP (1 mM), K(ATP)-channel activity was completely suppressed by 0.1 mM NBDP. 4. The L-isomer of N-benzoyl-phenylalanine displayed a 20 fold lower affinity and an 80 fold lower potency than the D-isomer. 5. Introduction of a p-nitro substituent in the D-phenylalanine moiety of NBDP did not decrease lipophilicity but lowered affinity and potency by more than 30 fold. 6. Introduction of a p-amino substituent in the D-phenylalanine moiety of NBDP (N-benzoyl-p-amino-D-phenylalanine, NBADP) reduced lipophilicity and lowered affinity and potency by about 10 fold. This loss of affinity and potency was compensated for by formation of the phenylpropionic acid derivative of NBADP. A similar difference in affinity was observed for the sulphonylurea carbutamide and its phenylpropionic acid derivative. 7. Replacing the benzene ring in the D-phenylalanine moiety of NBDP by a cyclohexyl ring increased lipophilicity, and the K(D) and EC50 values were slightly lower than for NBDP. Exchange of both benzene rings in NBDP by cyclohexyl rings further increased lipophilicity without altering affinity and potency. 8. This study shows that N-acylphenylalanines interact with the sulphonylurea receptor of pancreatic beta-cells in a stereospecific manner. Their potency depends on lipophilic but not aromatic properties of their benzene rings. As observed for sulphonylureas, interaction of N-acylphenylalanines with the sulphonylurea receptor does not induce complete inhibition of K(ATP)-channel activity in the absence of inhibitory cytosolic nucleotides.  相似文献   

14.
OBJECTIVE: To determine the incidence of heterosexual human immunodeficiency virus type 1 disease transmission and the effect of zidovudine therapy on this risk of transmission. DESIGN: A cohort of 436 monogamous seronegative female sexual partners of human immunodeficiency virus type 1-infected males was followed up for 740 person-years with regular structured interviews and laboratory tests. PATIENTS: At enrollment of the women, 50% of their infected partners had one or more signs of disease progression (symptoms of acquired immunodeficiency syndrome, p24 antigen positivity, or CD4+ cell counts lower than 0.4 x 10(9)/L) and 15% were treated with zidovudine. MAIN OUTCOME MEASURE: Incidence rates of seroconversion were calculated and relative risks were estimated as incidence rate ratios. RESULTS: Twenty-seven women seroconverted during follow-up, and the incidence of seroconversion was 3.7 per 100 person-years. Seroconversion was about six times more frequent (relative risk, 5.8; 95% confidence interval, 2.2 to 15.3) in couples not using condoms. Men with signs of disease progression transmitted infection to their partners more frequently and were more frequently treated with zidovudine. When the risk of transmission was estimated accounting for disease progression, the rate of transmission in zidovudine-treated men was lower than in untreated men (relative risk, 0.5; 95% confidence interval, 0.1 to 0.9). CONCLUSION: Treatment of human immunodeficiency virus type-1 infected men with zidovudine reduces, but does not eliminate, heterosexual transmission of infection. Behavioral counseling that encourages sexual practices with a lower risk of transmission remains the most important method of prevention.  相似文献   

15.
To determine whether serum hepatitis C virus (HCV) RNA disappearance after interferon (IFN) treatment prevents development of hepatocellular carcinoma (HCC), we evaluated retrospectively the incidence of HCC in patients with chronic hepatitis C. A total of 213 patients were monitored for more than 6 months after completion of IFN treatment. Sixty-three of the 213 patients (29.6%) achieved a complete response (CR) to treatment and 150 (70.4%) had no response (NR). HCC developed in 12 (5.6%), all of whom were NR. Logistic analysis showed age, alpha -fetoprotein, and staging of histological finding before IFN treatment were independent factors to development of HCC. The fact that there was no HCC development from CR provides a basis for IFN treatment in chronic HCV infection.  相似文献   

16.
BACKGROUND: Because occupational blood contact places health-care workers at risk for infection with bloodborne pathogens, we wanted to estimate the prevalence of infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) among hospital-based surgeons and correlate the results with occupational and nonoccupational risk factors. STUDY DESIGN: All surgeons in training or in practice in general surgery, obstetrics and gynecology, or orthopedics at 21 hospitals in moderate to high AIDS incidence areas were eligible to participate in a voluntary, anonymous serosurvey. Serum samples were tested for HIV antibody, for HCV antibody, and for markers of HBV infection: hepatitis B surface antigen, total antibody to hepatitis B core antigen, and antibody to hepatitis B surface antigen. RESULTS: Of 2,887 eligible surgeons, 770 (27 percent) participated in the study. One of 740 surgeons not reporting nonoccupational risk factors was HIV seropositive (0.14 percent, upper limit 95 percent confidence interval [CI] equals 0.64 percent). None of 20 participants reporting nonoccupational HIV risk factors and none of ten not responding to the question on nonoccupational risk factors were HIV positive. Of 129 (17 percent) participants with past or current HBV infection, three (0.4 percent) had chronic HBV infection; all were negative for hepatitis B e antigen. Risk factors for HBV infection included not receiving hepatitis B vaccine (odds ratio [OR] 14.7, 95 percent CI 8.3 to 26.0) and practicing surgery at least ten years (OR 2.2, 95 percent CI 1.3 to 3.8). Seven (0.9 percent) participants had anti-HCV. CONCLUSIONS: Although not necessarily generalizable to all surgeons in moderate to high AIDS incidence areas, these results do not indicate a high rate of previously undetected HIV infection among surgeons who trained or practiced in these areas, or both. Hepatitis B virus posed the highest risk of infection with a bloodborne pathogen, followed by HCV and HIV.  相似文献   

17.
Patients with AIDS who are receiving optimal medical care, including combination therapy with antiretroviral agents and more effective prophylaxis and therapy for opportunistic infections and neoplasms, are surviving longer. However, the potential for drug interactions in these patients is increased because many of the currently used antibiotics and antiviral agents have profound effects on the hepatic cytochrome P-450 enzyme system, on renal tubular function, and on bone marrow function. In this AIDS Commentary, Dr. Piscitelli and colleagues have succinctly reviewed the current state of our knowledge regarding the potential for additive or synergistic drug interactions that can result in enhanced toxicity or, alternatively, augmented therapeutic benefit. Information on these interactions will become more important as more intensive and effective therapy becomes available for persons with far-advanced infection due to human immunodeficiency virus type 1.  相似文献   

18.
To investigate the involvement of T-cell response against hepatitis C virus (HCV) antigens in viral clearance after interferon therapy, we measured interleukin-2 (IL-2) production by peripheral mononuclear cells in response to HCV core in patients with chronic hepatitis C. In a cohort of 43 patients, we investigated the frequency of circulating core-specific T-helper (Th) cell precursors by the limiting-dilution assay, and in a second cohort of 60 patients, we analyzed the response to specific core epitopes using 52 synthetic 15-mer overlapping peptides. We observed that the frequency of core-specific Th cell precursors was significantly higher in patients with sustained biochemical and virological response (SR) after interferon (IFN) therapy (median, 1/55,736) than in untreated patients (1/274,023) or that in patients who remained viremic after completion of the treatment-nonresponders (NR) plus transient responders (TR) (1/1,909,972). Patients who failed to respond to IFN (NR) and those who relapsed after IFN discontinuation (TR) had a similarly low number of precursors. The number of core peptides recognized by SR, TR, NR, UT, and healthy controls was 8.2 +/- 1.5, 6.5 +/- 1.2, 2.0 +/- 0.5, 2.7 +/- 0.9, and 0.3 +/- 0.2, respectively. In SR, the intensity of the proliferative response to core peptides as estimated by the summation of stimulation indexes (sigmaSI) was significantly higher than in NR and than in UT, but not different from that of TR. Our results indicate that both expansion of HCV-specific Th cell precursors and Th cell recognition of multiple core epitopes seem to be important in the elimination of HCV after IFN therapy.  相似文献   

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In order to analyze the etiology, cytological and biochemical characteristics, and outcome of pleural disease in patients infected with HIV, the medical records of 86 HIV-positive patients with pleural effusion were reviewed. Controls were 106 HIV-negative patients with parapneumonic or tuberculous effusion. Most HIV-positive patients were intravenous drug abusers (95.3%). Pleural effusions in HIV-positive patients were caused by infections in 76 (89.4%) cases. Parapneumonic effusion was diagnosed in 59 patients and tuberculous pleuritis in 15 patients. Staphylococcus aureus was the most frequently isolated bacteria. Parameters for differentiating complicated cases of parapneumonic exudate from uncomplicated cases, such as pleural fluid pH < 7.20 (sensitivity 80% vs. 84.3%), pleural fluid glucose < 35 mg/dl (sensitivity 45% vs. 56.25%) pleural fluid LDH > 1600 UI/l (sensitivity 85% vs. 62.50%), showed similar sensitivity in HIV-positive and HIV-negative patients. Monocytes in pleural fluid were significantly decreased in tuberculous pleuritis in HIV-positive patients (506 +/- 425 vs. 1014 +/- 1196 monocytes/ml, p < 0.05). No significant differences were detected in the outcome of HIV-positive and HIV-negative patients with pleural disease. It can be concluded that the pleural effusion was of predominantly infectious etiology in HIV-positive patients from populations with a high prevalence of intravenous drug abuse. Neither the biochemical parameters in pleural fluid nor the outcome differed significantly between HIV-positive and HIV-negative patients.  相似文献   

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