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Biomedical subjects

J Guardia

Publications and source records attributed to J Guardia.

At least 37 records · Page 2Linked to original sources
PubMed2001

Two years of lamivudine therapy in anti-HBe-positive patients with chronic hepatitis B.

There is no standard therapy for patients with anti-HBe-positive chronic hepatitis B. The aims of this study were to analyse the efficacy of lamivudine therapy for two years in these patients and to study the sequence variations in the precore and polymerase hepatitis B virus (HBV) regions in relation to therapy. Sixteen patients with chronic anti-HBe-positive hepatitis were treated with lamivudine (100 mg) once daily for 2 years. Levels of alanine aminotransferase (ALT), HBV-DNA and HBsAg were monitored during therapy. The polymerase and precore genes were amplified by polymerase chain reaction and their products were sequenced directly. Thirteen of 16 patients (81%) had a virological and biochemical response after 1 year of therapy and 11 (69%) maintained the complete response after 2 years of lamivudine therapy. Among the three patients without initial virological or biochemical response at year 1, prolonging therapy to 2 years was not associated with an increase in the response. YMDD variants were detected in 19% of cases in the first year and in 44% in the second year: YVDD being the most frequent mutations detected during year 1 and YIDD during year 2 of therapy. YMDD variants were found in 7-27% of cases with complete response depending on the duration of therapy. Our results show that prolonging lamivudine therapy is safe, well tolerated and maintains viral inhibition in anti-HBe-positive patients. However, its efficacy tends to decrease overtime and it is associated with an increase in YMDD variants, even in some cases, of complete response.

Adolescent↗
PubMed2001

Quantitative detection of hepatitis B virus DNA in serum by a new rapid real-time fluorescence PCR assay.

A sensitive and accurate HBV DNA quantification assay is essential for monitoring hepatitis B virus (HBV) replication. This study evaluated a real-time PCR method performed in the LightCycler analyser for quantitative HBV DNA assay. HBV DNA results with this method were compared with those obtained using a branched-chain DNA (bDNA) solution hybridization assay. Real-time PCR was performed using two adjacent fluorescently labelled probes and primers corresponding to the HBV core gene. The same standard employed in the bDNA assay was used for calibration. Serum samples came from 193 HBV surface antigen (HBsAg)-positive patients (34 HBV e antigen (HBeAg)-positive and 93 with antibody to HBeAg (anti-HBe)), and 66 asymptomatic HBV carriers. In addition, we analysed serum samples from 8 anti-HBe-positive patients who had been receiving lamivudine treatment for more than three years. A linear standard curve was seen in the range from 10(3) to 10(8) copies/mL. In the reproducibility analysis, intra-assay coefficient of variation (CVs) at two known HBV DNA concentrations were 4% and 2% and interassay CVs were 6% and 4%. The median of serum HBV DNA by real-time PCR was 9.2 x 10(8) copies/mL in HBeAg-positive patients with persistently elevated alanine aminotransferase (ALT) levels, 1.3 x 10(7) copies/mL in anti-HBe-positive cases with persistently elevated ALT levels, 3.7 x 10(4) copies/mL in anti-HBe-positive patients with fluctuating ALT levels and 10(4) copies/mL in asymptomatic HBV carriers. The differences in HBV DNA levels among the various groups studied were statistically significant (P < 0.05). The cut-off between chronic hepatitis patients and asymptomatic carriers was found to be at a serum HBV DNA concentration of 5 x 10(4) copies/mL. Of the 109 serum samples with a viral load < 7.5 x 10(5) (negative by bDNA assay) 44 (40%) were positive by real-time PCR: 24 (56%) chronic hepatitis and 20 (33%) asymptomatic carriers. There was a positive association between HBV DNA levels determined by real-time PCR and ALT levels (P < 0.05), which was not observed with the bDNA assay for HBV DNA quantification. At 12 months of lamivudine treatment, 6 patients (75%) showed HBV DNA levels < 5 x 10(4) copies/mL (range < 10(3)-2 x 10(3)), significantly lower than at baseline. At 36 months, 2 of 8 (25%) showed HBV DNA levels persistently lower than 5 x 10(4) copies/mL (1.7 x 10(3), 6 x 10(3)). The LightCycler quantitative real-time PCR is a practical, sensitive, reproducible single-tube assay with a wide dynamic range of detection. The assay is automatic except for DNA extraction and the running time is only 70 min. The LightCycler real-time PCR is useful for identifying different states of HBV infection and for evaluating the efficacy of viral therapy.

DNA, Viral↗
PubMed2001

Role of hepatitis B, C, and D viruses in dual and triple infection: influence of viral genotypes and hepatitis B precore and basal core promoter mutations on viral replicative interference.

The interactions among hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis delta virus (HDV) were studied by measuring HBV-DNA and HCV-RNA levels and by determining the influence of viral genotypes and mutations in HBV basal core promoter (BCP) and precore regions. We included 65 consecutive patients, 25 HBV/HCV, 18 HBV/HDV, and 22 HBV/HCV/HDV. Controls consisted of 55 patients with chronic HBV and 55 with chronic HCV infection. HBV-DNA and HCV-RNA levels were lower in coinfections than in single infections (P <.05). HBV/HCV coinfection was associated with lower HBV viremia (8.2 x 10(4) copies/mL) and lower HCV-RNA levels (7 x 10(5) IU/mL), than the corresponding control group (P <.05), with more marked decrease in HBV replication (P <.05). Moreover, in HBV/HCV coinfection and in triple coinfection we observed an inverse relationship between HBV-DNA and HCV-RNA levels (P <.05). HBV/HDV coinfection was associated with lower HBV viremia (2.5 x 10(4) copies/mL) than that found in HBV infection (P <.05). Patients with triple coinfection showed lower HBV-DNA and HCV-RNA levels than control groups (P <.05). Prevalence of precore mutations was lower in HCV coinfections (P <.05). No significant association was observed between HCV-RNA levels and HBV precore mutations, BCP mutations or HBV genotypes, or between HBV-DNA levels and HCV genotypes (P <.05). In conclusion, HCV exhibited stronger inhibitory action in the reciprocal inhibition seen in HBV/HCV coinfection. HDV was the dominant virus in HBV/HDV coinfection and in triple coinfection, and had a greater unfavorable influence on HCV than on HBV replication. The reciprocal inhibition of viral replication seemed to be little influenced by the inherent genomic factors studied.

Adult↗
PubMed2001

Interferon and ribavirin combination therapy for chronic hepatitis C in human immunodeficiency virus-infected patients with congenital coagulation disorders.

We have conducted an open, prospective trial to assess the safety and efficacy of interferon alfa-2b and ribavirin in combination for the treatment of chronic hepatitis C in human immunodeficiency virus (HIV)-infected hemophiliacs. Twenty hemophiliacs coinfected with HIV and hepatitis C virus (HCV), 18 of them under highly active antiretroviral therapy (HAART), with a mean CD4(+) cell count of 490 +/- 176 cells/mm(3) and undetectable (n = 9) or low-level HIV RNA (<10,000 copies/mL; n = 11), were treated with interferon-alfa2b (3 MU thrice weekly) and ribavirin (800 mg/d) for 6 or 12 months according to virologic response. Patients were monitored for tolerance and response at 4, 8, 12, 24, 36, and 48 weeks during treatment and every other month thereafter. All 20 patients enrolled completed at least 6 months of treatment with no major side effect requiring treatment withdrawal, dose reduction, or modification of HAART. Overall, 8 patients (40%) achieved a sustained virologic response at the end of the 6-month post-treatment follow-up. Sustained responders had lower baseline HCV-RNA levels (5.7 +/- 0.8 vs. 6.3 +/- 0.4 log10 IU/mL, P =.041) but were otherwise similar to nonresponders. All sustained responders had a decrease in HCV-RNA level of at least 1 log per month during the first 2 months and undetectable levels at 6 months. In conclusion, our results provide evidence that combination therapy with interferon and ribavirin is safe in HIV-infected hemophiliacs with stable CD4 cell count and undetectable or low-level HIV replication, and leads to eradication of HCV in 40% of these patients.

Adult↗
PubMed2001

Neuropsychological long-term sequelae of perinatal asphyxia.

OBJECTIVE: To investigate the long-term neuropsychological consequences of perinatal asphyxia (PA). METHODS: A group of adolescents were assessed with antecedents of mild (n = 8) and moderate (n = 20) PA, and a matched group of 28 healthy adolescents as a control group. Neuropsychological assessment included tests of memory, perceptual-motor skills, and frontal lobe functions, because these are areas of cognitive functioning susceptible to hypoxic conditions. RESULTS: Subjects with moderate PA showed significant differences from the control group on tests related to delayed recall for both verbal and visual information, perceptual-motor speed, and tests assessing attention and executive functions. Conversely, subjects in the mild PA group exhibited scores which were similar to those of the control group in all the assessed variables. CONCLUSION: The present findings demonstrate that subtle but persistent neuropsychological deficits were observed in adolescents with antecedents of moderate PA, but not in those classified with mild asphyxia.

Adolescent↗
PubMed2001

Longitudinal evaluation of the structure of replicating and circulating hepatitis C virus quasispecies in nonprogressive chronic hepatitis C patients.

In previous cross-sectional studies, we demonstrated that, in most patients with chronic hepatitis C, the composition and complexity of the circulating hepatitis C virus (HCV) population do not coincide with those of the virus replicating in the liver. In the subgroup of patients with similar complexities in both compartments, the ratio of quasispecies complexity in the liver to that in serum (liver/serum complexity ratio) of paired samples correlated with disease stage. In the present study we investigated the dynamic behavior of viral population parameters in consecutive paired liver and serum samples, obtained 3 to 6 years apart, from four chronic hepatitis C patients with persistently normal transaminases and stable liver histology. We sequenced 359 clones of a genomic fragment encompassing the E2(p7)-NS2 junction, in two consecutive liver-serum sample pairs from the four patients and in four intermediate serum samples from one of the patients. The results show that the liver/serum complexity ratio is not stable but rather fluctuates widely over time. Hence, the liver/serum complexity ratio does not identify a particular group of patients but a particular state of the infecting quasispecies. Phylogenetic analysis and signature mutation patterns showed that virtually all circulating sequences originated from sequences present in the liver specimens. The overall behavior of the circulating viral quasispecies appears to originate from changes in the relative replication kinetics of the large mutant spectrum present in the infected liver.

Adult↗
PubMed2001

Morphologic capillary changes and manifestations of connective tissue diseases in patients with primary biliary cirrhosis.

The objective of this study was to investigate the presence of nailfold capillary abnormalities and extrahepatic signs of connective tissue disease in patients with primary biliary cirrhosis (PBC), as compared to patients with other chronic liver diseases. We evaluated 22 patients with PBC and 15 patients with other chronic liver diseases as a control group. Nailfold capillaroscopy was performed by two observers blinded to clinical findings using a Wild M3 stereomicroscope with an Intralux 5000 Volpi cold light lamp. We detected nailfold capillary abnormalities in 20 out of 22 (91%) PBC patients. Twelve of these 20 patients (54%) showed capillary alterations characteristic of systemic sclerosis. In the control group only two out of 15 patients (13%) presented alterations and in both cases they were a non-specific type. The presence of nailfold capillary abnormalities was significantly greater in PBC patients than in the control group (P < 0.001). Eleven out of the 22 PBC patients (50%) had extrahepatic signs of connective tissue disease and most of them were related to systemic sclerosis; patients with other chronic liver diseases did not present rheumatic manifestations (P < 0.001). In PBC patients there was a significant association between systemic sclerosis capillary pattern and rheumatic manifestations (P < 0.03). The high prevalence of nailfold capillary abnormalities characteristic of systemic sclerosis in patients with PBC and the correlation with sclerodermal manifestations suggests that this capillaroscopic finding could be a useful indicator to investigate rheumatic manifestations in these patients.

Adult↗
PubMed2000

Nitrovasodilators, low-dose aspirin, other nonsteroidal antiinflammatory drugs, and the risk of upper gastrointestinal bleeding.

UNLABELLED: BACKGROUND The relation between medications that release nitric oxide, such as nitroglycerin and other nitrovasodilators, and upper gastrointestinal bleeding is uncertain. In animals, these medications reduce the gastric damage induced by nonsteroidal antiinflammatory drugs. Nitric oxide, however, inhibits platelet aggregation and may contribute to bleeding from an ulcer. METHODS: We performed a case-control study to determine the risk of bleeding in patients taking nitrovasodilators, low-dose aspirin, or other nonsteroidal antiinflammatory drugs. The case group was made up of 1122 consecutive patients admitted to one of four hospitals with bleeding from a peptic lesion. The 2231 control subjects were 1109 patients hospitalized for other reasons and 1122 outpatients from the same geographic area. RESULTS: In the week before admission, 520 (46.3 percent) of the patients with bleeding had taken a nonsteroidal antiinflammatory drug other than low-dose aspirin, 120 (10.7 percent) had taken low-dose aspirin (< or = 300 mg per day), 60 (5.3 percent) a nitrovasodilator, and 135 (12.0 percent) an antisecretory agent such as a histamine H2-receptor antagonist or a proton-pump inhibitor. In multivariate models that adjusted for age, sex, and clinical risk factors, the use of a nonsteroidal antiinflammatory drug other than low-dose aspirin was independently associated with an increased risk of bleeding from a peptic ulcer (odds ratio, 7.4; 95 percent confidence interval, 4.5 to 12.0), as was the use of low-dose aspirin alone (odds ratio, 2.4; 95 percent confidence interval, 1.8 to 3.3). The use of a nitrovasodilator was associated with a decreased risk of bleeding (odds ratio, 0.6; 95 percent confidence interval, 0.4 to 0.9), as was antisecretory therapy (odds ratio, 0.6; 95 percent confidence interval, 0.4 to 0.8). In patients taking any type of nonsteroidai antiinflammatory drug, the use of a nitrovasodilator or antisecretory therapy was independently associated with a decreased risk of bleeding. CONCLUSIONS: The use of nitrovasodilator drugs is independently associated with a decreased risk of upper gastrointestinal bleeding.

Aged↗
PubMed2000

[Prevalence and incidence of hepatitis A in patients with hepatitis B and C].

BACKGROUND: Patients with chronic hepatitis are in risk to acquire a fulminant hepatitis associated with hepatitis A virus superinfection. PATIENTS AND METHODS: Antibodies against hepatitis A were study in serum from 353 patients with chronic hepatitis B or C. RESULTS: The prevalence of IgG-HAV antibodies was 81% in chronic hepatitis C patients, and 77% in chronic hepatitis B patients. The presence of anti-HAV antibodies was related to the patients' age. None case of acute hepatitis A in chronic hepatitis patients was detected. CONCLUSIONS: The prevalence of anti-HAV antibodies is high in patients with chronic viral hepatitis but the incidence of the disease is low. Hepatitis A vaccination should do with previously screening.

Adolescent↗
PubMed2000

Utility of early testing for HCV viremia as predictive factor of sustained response during interferon or interferon plus ribavirin treatment.

BACKGROUND/AIM: To evaluate the utility of early testing for hepatitis C viremia as a predictor of treatment outcome during interferon or combination therapy. METHODS: We studied 184 patients with chronic hepatitis C who received interferon and were monitored for HCV RNA. Sixty-two patients received interferon alone for 12 months and 122 patients, who were still HCV RNA positive at 2 months, received an additional 12-month course of interferon and ribavirin combination therapy. RESULTS: Using this strategy, sustained response occurred in a total of 34 patients (18.5%). Independent variables associated with sustained response were HCV genotype (p=0.06), viral load < or = 5.1 logs/ml (p= 0.005) and negative HCV RNA at 1 month (p<0.0001) in the interferon group, and female sex (p=0.04), genotype (p=0.03), viral load < or = 5.5 logs/ml (p=0.01), normal ALT (p=0.001) and decline in viral load > or = 1.2 logs/ml after 2 months of interferon monotherapy (p<0.001) and negative viremia at 5 months of ribavirin onset (p<0.0001) in the combination therapy group. Persistence of viremia at 1 month of interferon monotherapy and at 5 months of combination therapy were the strongest predictors of non-response (negative predictive value of 100% and 99%, respectively). CONCLUSIONS: Qualitative assessment of HCV RNA during treatment is the strongest predictor of sustained response during interferon or combination therapy for chronic hepatitis C.

Adult↗
PubMed2000

Nitric oxide may contribute to nocturnal hemodynamic changes in cirrhotic patients.

OBJECTIVE: Patients with liver cirrhosis have a nocturnal worsening of hemodynamic parameters that has been associated with an increased risk of variceal bleeding at nighttime. The aim of this study was to investigate whether nitric oxide and cytokines are implicated in these hemodynamic changes. METHODS: Ten cirrhotic patients and eight controls were studied. Mean blood pressure, heart rate, plasma norepinephrine, tumor necrosis factor alpha and interleukin-6 levels, and serum nitrite + nitrate levels were determined at 0800, 1600, and 2400 h. All determinations were performed in supine rest and at least 4 h after meals. In a second study, nitrite + nitrate levels were assessed in 10 cirrhotic patients before and after eating a standard meal. RESULTS: Mean arterial pressure levels that were always lower in the patient group showed a nocturnal decrease in both groups of subjects. Heart rate values that were always higher in cirrhotic patients showed a nocturnal fall in controls, whereas cirrhotics maintained elevated values at nighttime. Norepinephrine levels were higher in cirrhotics and maintained similar values during the study, whereas controls had a significant nocturnal decrease. Nitrite + nitrate levels that were higher in cirrhotic patients showed a significant mean increase of 40% from morning (0800 h) to night (2400 h) in the patient group, whereas in controls no change was observed (p < 0.05). Tumor necrosis factor alpha and interleukin-6 levels did not change either in patients or controls during the entire period. Cirrhotic patients with or without ascites maintained a pattern of hemodynamic and biochemical changes similar to the pattern observed in the entire group of patients. Finally, no changes in serum nitrite + nitrate levels were observed in patients before and after eating the standard meal. CONCLUSION: An increased nocturnal nitric oxide production might contribute to the hemodynamic changes observed in cirrhotic patients during nighttime.

Aged↗
PubMed2000

Striatal dopaminergic D(2) receptor density measured by [(123)I]iodobenzamide SPECT in the prediction of treatment outcome of alcohol-dependent patients.

OBJECTIVE: The authors' goal was to study striatal dopaminergic dopamine 2 (D(2)) receptors as a biological marker of early relapse in detoxified alcoholic patients by using [(123)I]iodobenzamide ([123I]IBZM) single photon emission computed tomography (SPECT). METHOD: The authors performed [(123)I]IBZM SPECT on 21 alcohol-dependent inpatients during detoxification and on nine healthy volunteers, using the ratios of basal ganglia to occipital lobes for SPECT quantification. Depending on treatment outcome 3 months after hospital discharge, patients were determined to be relapsers or nonrelapsers. RESULTS: Alcohol-dependent subjects with early relapse (within 3 months after hospital discharge) showed a higher uptake of [(123)I]IBZM in the basal ganglia during detoxification (mean ratio=1.83, SD=0.9) than patients who did not have early relapse (mean ratio=1.69, SD=0.11). CONCLUSIONS: These results suggest that low levels of dopamine, or an increased density of free striatal dopaminergic D(2) receptors, could be related to early relapse in alcohol-dependent patients. Therefore, [(123)I]IBZM SPECT could become a biological marker of vulnerability to relapse for alcoholic patients in recovery.

Adult↗
PubMed2000

Treatment with interferon plus ribavirin in anti-HIV negative patients with congenital coagulation disorders and chronic hepatitis C.

BACKGROUND: Hepatitis C virus (HCV) infected hemophiliacs respond at low rate to interferon (IFN) monotherapy. AIMS: To assess efficacy of IFN and RBV in HIV negative hemophiliacs with chronic hepatitis C and identify early predictive factors of response. METHODS: Twenty naive patients were treated with interferon and RBV for twelve months. Response was assessed by both serial ALT and HCV RNA levels. RESULTS: Normalization of ALT with clearance of HCV RNA occurred in seven (35%) patients. Age and age at infection were the only features associated with a higher likelihood of response. In all responders the viral load had decreased by at least one log within two months of starting treatment. CONCLUSIONS: Combination of interferon and ribavirin is well tolerated by hemophiliacs who achieve similar sustained response rates to non-hemophiliacs. Quantitative assessment of viral load at two months of treatment is a useful method to identify non-responders at an early stage.

Adolescent↗