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J Costa

Publications and source records attributed to J Costa.

At least 199 records · Page 11Linked to original sources
PubMed1990

Risk factors for hepatocellular carcinoma in Catalonia, Spain.

The influence of hepatitis B virus infection, alcohol consumption, tobacco smoking and use of oral contraceptives on the risk of hepatocellular carcinoma (HCC) was evaluated in a hospital-based case-control study in Catalonia, in the Mediterranean coastal area of north-eastern Spain. A total of 96 HCC cases (86.5% of them with associated liver cirrhosis) and 190 age- and sex-matched controls were studied. The odds ratio of HCC and 95% confidence interval among hepatitis B surface antigen (HBsAg) carriers was 4.9 (1.3-21.9). The OR was not significantly elevated in smokers, and a marginally significant increased risk was found among users of oral contraceptives based on 6 female cases. There was a significant dose-response relationship between alcohol consumption and risk of HCC (chi 2 for trend: 24.3, p less than 0.001). Although hepatitis B infection was strongly associated with HCC, alcohol abuse leading to cirrhosis appears to be one of the main causes of HCC in this region.

Adult↗
PubMed1990

Hepatitis C virus infection in patients with nonalcoholic chronic liver disease.

STUDY OBJECTIVE: To determine the prevalence and meaning of antibodies to the hepatitis C virus (HCV) in patients with nonalcoholic chronic liver diseases. DESIGN: Cross-sectional study. SETTING: The liver unit of a referral-based university hospital. PATIENTS: Three hundred and forty-six consecutive patients, including 137 with cryptogenic chronic liver disease, 156 with chronic hepatitis B, 47 with primary biliary cirrhosis, and 8 with persistently abnormal aminotransferase serum levels and normal liver histology. Among patients with cryptogenic liver disease, 41 received blood transfusions before discovery of liver disease and 18 had circulating nonorgan-specific autoantibodies. For comparison, 1495 apparently healthy volunteer blood donors were included in the study. LABORATORY INVESTIGATIONS: The presence of anti-HCV antibodies (anti-HCV) was determined by a recently developed enzyme-linked immunoassay. MEASUREMENTS AND MAIN RESULTS: In patients with cryptogenic liver disease, the prevalence of anti-HCV was 82% (95% CI, 76% to 89%), being higher (P = 0.02) in patients with histories of blood transfusion than in those with unknown sources of exposure. Antibodies to HCV were not detected in patients with antinuclear antibodies at high titer. Among patients with chronic hepatitis B, anti-HCV were found in 11% (CI, 5% to 18%) of those with hepatitis B virus (HBV)-associated DNA in serum and in 29% (CI, 17% to 43%) of those with undetectable HBV replication (P less than 0.05). The prevalence of anti-HCV in blood donors was 1.2% (CI, 1.1% to 1.3%). CONCLUSIONS: Our results indicate that HCV infection probably plays an important etiologic role in cryptogenic liver disease and, in some patients, in chronic hepatitis B. Determining whether anti-HCV are present appears to be useful for differentiating viral from autoimmune chronic liver diseases.

Adolescent↗
PubMed1990

Dibucaine interaction with phospholipid vesicles. A resonance energy-transfer study.

Resonance energy transfer between a local anaesthetic, dibucaine (donor) and a set of functionalized probes [n-(9-anthroyloxy)stearic acids, n = 2, 3, 6, 7, 9 and 12 and 16-(9-anthroyloxy)palmitic acid] (acceptors) was found to be an efficient process with a critical radius of transfer Ro = 2.1 nm, this interaction being used to locate the drug in a model membrane system, small unilamellar vesicles of dipalmitoylglycerophosphocholine, both above and below the temperature of the gel-to-the-liquid-crystal transition of the phospholipid. From the sequence of relative quenching efficiencies of dibucaine fluorescence upon incorporation of the probes, it was concluded that the drug intercalates in the membrane near the glycerol backbone of the lipid. In addition, it was found that dibucaine location is not significantly affected upon crossing the phase-transition temperature of the phospholipid. Dibucaine photophysics was also studied and the short lifetime of the neutral form of the anaesthetic with respect to that of the monoprotonated species was attributed to an intramolecular charge-transfer interaction. From the study of its partition coefficient between the membrane and the aqueous phase, it was concluded that the only significant species present in the membrane is the charged one.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1990

Hepatitis B virus and hepatitis D virus replication in HBsAg-positive fulminant hepatitis.

Hepatitis B virus DNA and hepatitis D virus RNA, the most sensitive markers of hepatitis B and hepatitis D virus replication, were sought by molecular hybridization with radioactive probes in serial serum samples from 29 consecutive patients with HBsAg-positive fulminant hepatitis. Nineteen patients had evidence of hepatitis D virus infection, as assessed by the presence in serum of delta antigen, anti-delta antibodies, or both. Hepatitis B virus DNA was found in only two patients: one was a chronic HBsAg carrier with hepatitis D virus superinfection and the other had fulminant hepatitis caused by hepatitis B and hepatitis D coinfection. Hepatitis D virus RNA was detected in three patients: two with hepatitis B and hepatitis D coinfection and also in the HBsAg carrier with positive hepatitis B virus DNA and hepatitis D virus superinfection. None of 10 patients with hepatitis B virus infection alone had detectable viral nucleic acids in serum. Overall, viral nucleic acids were detected in the sera of 4 of the 29 patients (14%). Hepatitis D virus antigenemia did not indicate hepatitis D virus replication because hepatitis D virus RNA was not detected in 9 of 12 patients with hepatitis D virus antigen in their sera. The low frequency of viral replication found in fulminant hepatitis B or D may explain the low recurrence rate of viral hepatitis in patients with fulminant hepatitis who have received liver transplantations.

Adolescent↗
PubMed1990

Subjective neuroleptic response and treatment outcome under open and double-blind conditions--a preliminary report.

1. A patient's early subjective response to a neuroleptic was recorded in 17 schizophrenic patients following a fixed dose of neuroleptic under both open and double-blind placebo-controlled conditions. 2. High correlations were found between a patient's subjective response at 2.5, 24 and 48 hours after the initial dose, suggesting that the timing of the initial subjective response rating is not critical. 3. The relationship between the psychiatric improvement and subjective response was not significant under double-blind conditions (r = 0.004), while the relationship under the open condition showed a trend towards significance comparable to earlier reports (r = 0.32). 4. The findings question the usefulness of applying early subjective response to a neuroleptic to predict clinical improvement.

Adult↗
PubMed1990

Abnormal EEG responses to photic stimulation in schizophrenic patients.

Numerous studies have differentiated schizophrenic patients and normal controls in electroencephalography (EEG) spectral patterns recorded at rest. We replicated the resting EEG spectral differences between these groups and observed significant differences in periodic photic stimuli on the EEG spectra. Drug-free schizophrenic male patients (n = 8, mean age = 23.9) and normal male controls (n = 11, mean age = 24.3) were studied. Eighty seconds of EEG were collected from each subject for each of four experimental conditions: one resting and three photic-driving conditions (2.38, 4.54, and 8.33 Hz). Eye movement and other movement artifacts were minimized by use of an automatic amplitude threshold filter. Although large eye movements could be excluded as confounding factors, the filter could not for certain exclude small eye movements. Subjects were instructed to keep their eyes closed throughout. A significant difference was found between the groups both at rest and following photic stimulation in EEG activity. This result was characterized by increased delta activity and decreased alpha activity in schizophrenic patients at rest. The EEG activity following the photic driving also differentiated the groups. Schizophrenic patients had decreased sensitivity to the photic stimulation in the alpha range for spectra derived from both fundamental and harmonic analysis.

Adult↗
PubMed1990

Incidence and features of liver disease in patients on chronic hemodialysis.

We examined the incidence and features of liver disease and the presence of serologic markers of hepatitis B virus (HBV) infection in 134 patients on hemodialysis for 2 to 14 years. Twenty-three patients (17%) had had a single episode of acute hepatitis while on dialysis and two patients had had two episodes, which were attributed to infection by hepatitis B virus in 7 instances and by hepatitis non-A, non-B virus in 20. Chronicity supervened in 4 cases of hepatitis B (57%) and in 14 cases of hepatitis non-A, non-B (70%). A prolonged rise of serum aminotransferases, which was not preceded by acute hepatitis, was detected in 23 additional patients (17%). Acute hepatitis and prolonged hypertransaminasemia were more frequent in patients dialyzed at a hospital unit than in patients dialyzed outside the hospital or at home. These observations indicate that development of acute and chronic liver disease, mainly hepatitis non-A, non-B, is frequent in patients on chronic hemodialysis, particularly in those dialyzed in hospital. Serologic evidence of current or past infection by HBV was detected in 57 patients (42%) with sustained positivity of HBV serum markers. Transient positivity for anti-HBc, anti-HBs, or both, possibly related to passive transmission of antibodies by blood transfusion, was observed in 20 patients (15%). These findings indicate that periodic, repeated testing for HBV serum markers is necessary only in a minority of patients on long-term hemodialysis.

Acute Disease↗
PubMed1989

[Severe acute hepatitis as initial manifestation of chronic hepatitis B virus infection].

Chronic hepatitis B virus (HBV) infection was revealed by a severe acute hepatitis with positive HBsAg in a patient. The positivity of IgM anti-HBc antibody, the rapid negativization of DNA-HBV, the early normalization of liver function tests and the exclusion of other causes of acute hepatitis favored the diagnosis of recent HBV infection and were predictive of a rapidly favorable outcome. However, immunohistochemical study of a transjugular hepatic biopsy sample discovered HBsAg within the liver, with a characteristic topographic distribution of chronic HBV infection. The patient's evolution confirmed this diagnosis, because 20 months later he had chronic active hepatitis with persistent replicative activity of HBV. This case illustrates the heterogeneity of HBV infections, emphasizing the need of an accurate diagnosis and a careful follow up until the complete resolution of each case of acute hepatitis with positive HBsAg.

Acute Disease↗
PubMed1989

Prevalence of antibodies to hepatitis C virus in Spanish patients with hepatocellular carcinoma and hepatic cirrhosis.

The prevalence of antibodies against hepatitis C virus (HCV) was investigated in 96 patients with hepatocellular carcinoma, 106 patients with liver cirrhosis without evidence of cancer, and 177 controls without liver disease. 75% of patients with hepatocellular carcinoma had HCV antibodies (anti-HCV), a significantly higher proportion than that observed in patients with cirrhosis (55.6%), or controls (7.3%). The prevalence of anti-HCV was significantly higher in patients with alcoholic cirrhosis and hepatocellular carcinoma (76%) than in patients with alcoholic cirrhosis alone (38.7%) whereas in patients with cryptogenic cirrhosis there was no significant difference between those with and without primary liver cell cancer (81.4% and 77.5%, respectively). These results indicate that HCV infection may have a role in the pathogenesis of hepatocellular carcinoma, even in patients with chronic liver disease apparently related to other agents such as alcohol, and that this recently identified hepatitis virus may be found in a large proportion of patients with cryptogenic cirrhosis.

Aged↗
PubMed1989

Drug advertising.

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Advertising↗
PubMed1989

EEG alpha photic driving abnormalities in chronic schizophrenia.

Periodic photic stimuli across the entire electroencephalographic (EEG) frequency range were used in an attempt to assess EEG functional differences between chronic schizophrenic patients and control subjects. The EEG responses to these photic stimuli were significantly attenuated in the schizophrenic patients, specifically at the frequencies within the EEG alpha range. The schizophrenic patients also showed an alpha range attenuation in the "no stimulus" EEG alpha measure, such that there was a significant correlation across subjects between the "stimulus" and "no stimulus" EEG alpha range abnormalities. These abnormalities are discussed with reference to possible dysfunctional thalamic mechanisms involved in the pacing of EEG alpha activity and the gating of information through the cerebral cortex.

Adult↗
PubMed1989

The hepatoprotective principle of Hypoestes triflora leaves.

Hypoestes triflora is frequently used in Rwandese native medicine to treat hepatic diseases. Premedication with a water extract of the leaves prevented the prolongation of the barbiturate sleeping time associated with carbon tetrachloride-induced liver damage in mice. The compound responsible for this protective activity was benzoic acid. Mice previously treated with benzoic acid also showed a significant diminution of the increased GOT and GPT levels seen after carbon tetrachloride administration.

Alanine Transaminase↗
PubMed1989

Idiopathic entero-colic lymphocytic phlebitis. A cause of ischemic intestinal necrosis.

Histological examination of the surgical specimens of three patients presenting with intestinal ischemic necrosis disclosed extensive lesions of lymphocytic phlebitis associated with thrombosis of different ages. Arterioles and arteries were not affected. The lymphocytic infiltrate was composed of a mixture of T- and B-lymphocytes. None of the patients showed clinical or laboratory evidence of systemic vasculitis. Follow-up ranged between 4 months and 5 years. There has been no recurrence necessitating reoperation. The etiology of this clinicopathological entity has not been elucidated.

Aged↗