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Biomedical subjects

O Fay

Publications and source records attributed to O Fay.

At least 19 recordsLinked to original sources
PubMed2003

Hepatitis A booster vaccination: is there a need?

Hepatitis A is one of the most common vaccine-preventable infectious diseases in the world. Effective vaccines against hepatitis A have been available since 1992, and they provide long-term immunity against the infection. However, there is no worldwide consensus on how long protection will last or whether there will be a need for hepatitis A virus (HAV) booster vaccinations in the future. In most countries, booster-vaccination policy is guided by manufacturers' recommendations, national authorities, or both. In June, 2002, a panel of international experts met to review the long-term immunogenicity and protection conferred by HAV vaccine in different population groups. Data have shown that after a full primary vaccination course, protective antibody amounts persist beyond 10 years in healthy individuals, and underlying immune memory provides protection far beyond the duration of anti-HAV antibodies. The group concluded that there is no evidence to lend support to HAV booster vaccination after a full primary vaccination course in a healthy individual. However, further investigations are needed before deciding if boosters can be omitted in special patient-groups.

Adolescent↗
PubMed2001

Surveillance for rotavirus in Argentina.

Group A rotaviruses are the major cause of severe gastroenteritis in young children worldwide. Because rotavirus vaccination appeared imminent, a nationwide surveillance program was organized between October 1996 and October 1998 in the largest Argentine cities. Surveillance for disease burden, rotavirus detection, and rotavirus typing was undertaken at nine locations. Results showed rotavirus to be associated with 42% of diarrhea admissions. Although the prevalent G types changed from year to year, common G types were found in 96% of the cases and were usually associated with common P types. Uncommon G types, G9 and G5, were found at low prevalence and uncommon G/P combinations occurred at almost every study site. These data suggest that a rotavirus vaccine could substantially decrease the rotavirus disease burden in Argentina, but that introduction of a vaccine should be accompanied by a concurrent surveillance system.

Age Distribution↗
PubMed2000

Epidemiology of gallstone disease in Argentina: prevalences in the general population and European descendants.

To assess gallstone disease prevalence in Argentina, a random sample of the Rosario City population was studied, considering already known associated factors, and analyzing ethnic groups living in the city. A total of 1,173 participants (69% response), both sexes, 20 years and older were studied. Each subject underwent an abdominal ultrasound examination, a blood test, and a standardized questionnaire. It was seen that gallstone disease prevalence (gallstones or cholecystectomy), overall was 20.5% (23.8% in women and 15.5% in men; (P = 0.0005), and was associated with age and body mass index in both sexes, and with pregnancy number and hypertriglyceridemia in women. As regards ancestors' nationalities, Italian and Spanish descendants presented higher prevalence rates for all age groups than those described in Italy and Spain. Thus far, in a subsample of 78% of nonparticipants submitted to a new home visit, presence of cholecystectomy or symptoms did not differ from participants, supporting the validity of our results.

Adult↗
PubMed2000

Molecular medicine: the present and the future.

In the recent past, major achievements have been obtained in the understanding of the molecular defects at the basis of several different diseases. The field of 'Molecular Medicine' has thus become more solid, and several reports have been published linking the basic molecular investigation to the clinical practice. In line with this new approach to medicine a Symposium was organized where the linkage between investigations in basic science could be explored in view of clinical disorders, and vice versa. in Rosario, Argentina, September 9-11, 1999, molecular biologists, molecular pathologists and clinicians discussed the molecular defects possibly at the basis of some common diseases. This report summarizes the presentations and discussions during the symposium.

Acquired Immunodeficiency Syndrome↗
PubMed1997

[Hepatitis A virus infection in children in Argentina: a pilot study].

UNLABELLED: The severity and/or the prognostic of infections with the hepatitis A virus (HAV) is related to the age at which the infection occurs. Since transmission of the virus occurs by the fecal-oral route, the prevalence and age-relate incidence of infection is determined by the adequacy of sanitation hygienic measures and the socio economic level of exposed populations. Thus, the disease is having an increasing impact in developing countries with improving sanitary standards whereas inhabitants of industrialized countries are particularly at risk while visiting under-developed countries. We have established a cooperative group for the serologic study of children range between six months to ten years old, without sintomatology of acute hepatitis. The patients live in Buenos Aires, San Justo, Trelew, Rosario and Tucumán cities. We studied 3699 children. The specific Ab-antiHAV IgG were measured by enzyme immunoassay with commercial available kits (Organon and-or Abbott). The variable of study were age, sex and water quality. RESULTS: 45.19% were of San Justo, 26.15% of Rosario, 13% of Buenos Aires, 8.37% of Trelew and 7.29% of Tucumán. We observed the highest of possibility percentage (%POS) in Tucumán (81.4%), followed by San Justo (57.8%), Rosario (46.5%), Trelew (41.99%) and Buenos Aires (29.4%). In all the cities the lowest %POS was found in children under three years old. Between three and six years old the results were variable and an increase in %POS was observed related to the growth. The global %POS was 51.56%. CONCLUSIONS: This study confirms Argentina as a high endemic country for HAV infection. A global vaccination program is the only strategy that has the potential to prevent recurrent epidemics of hepatitis A and its erradication.

Age Factors↗
PubMed1990

Recombinant interferon alfa-2b following prednisone withdrawal in the treatment of chronic type B hepatitis.

The aim of the study was to evaluate the safety and effectiveness of interferon alfa-2b, alone and following prednisone withdrawal, in patients with chronic type B hepatitis. Thirty-five patients (27 men and eight women) were randomly allocated to two treatment groups. Group I (n = 17) received 6 weeks of prednisone followed by interferon alfa-2b (INTRON A, Schering-Plough Corporation) 10 million units subcutaneously, three times a week for 16 weeks. Group II (n = 18) was used as an untreated control group for 24 weeks, after which they received 16 weeks of treatment with the same dose of interferon as Group I. Both groups were followed up for 24 weeks after treatment. In Group I, 10/17 patients (58.8%) eliminated hepatitis B e antigen; 8/17 (47.1%) developed antibodies to hepatitis B e antigen; 9/17 (52.9%) became hepatitis B virus DNA negative and 1/17 (5.9%) was hepatitis B surface antigen negative at the end of follow up. In Group II, during the control phase, 1/18 (5.5%) became hepatitis B e antigen negative. When treated with interferon, 7/15 (46.7%) eliminated the e antigen, and 6/15 (40%) developed antibodies to hepatitis B e antigen and were hepatitis B virus DNA negative at the end of follow up. Serum alanine aminotransferase reached normal levels in all seroconverted patients. Liver biopsies showed a marked reduction of inflammation and disappearance of hepatitis B core antigen in liver cell nuclei in almost all cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Serum HBV-DNA (hepatitis B virus DNA) in acute and chronic hepatitis B infection.

HBV DNA was measured in the sera of 69 patients with hepatitis B virus infections. Sixteen patients had acute hepatitis B, 24 had chronic active hepatitis (CAH), 6 had chronic persistent hepatitis (CPH), 5 had cirrhosis without CAH and 18 were asymptomatic HBsAg carriers. In patients with acute hepatitis B who recovered, HBV DNA was present in the serum transiently early in the illness. HBV DNA persisted in the serum in the two patients who developed chronic hepatitis. Sera of 23 of 24 patients with CAH were persistently positive for HBV DNA. There was no relationship between the quantity of HBV DNA in the serum and the histological intensity of activity. Thirteen of the 24 patients with CAH had histological evidence of cirrhosis in addition to CAH and HBV DNA was detected in the sera of all 13. The sera of 2 of 6 patients with CPH were positive for HBV DNA. In one it was positive only where there was clinical evidence of reactivation of HBV infection. The other patient subsequently developed CAH. Sera of 5 patients with established HBsAg positive cirrhosis but without evidence of CAH were negative for HBV DNA. Two of these patients had hepatocellular carcinoma. Sera of 18 asymptomatic anti-HBe positive carriers with normal ALT were negative for HBV DNA. HBeAg and HBV DNA were not always found in the serum together. In acute hepatitis 5 patients with HBV DNA in the serum were HBeAg positive, but in 6 patients the sera were HBeAg positive inthe absenceof HBV DNA.

Acute Disease↗
PubMed1987

Anti-delta antibody in various HBsAg positive Argentine populations.

One thousand five hundred and seventeen HBsAg carriers from different cities of Argentina were studied for the presence of anti-Delta antibody (anti-HDV) in their sera. One thousand one hundred and sixty-eight were volunteer blood donors and 349 were patients with liver disease. Different liver diseases were diagnosed by clinical, biochemical, and histological parameters. Among blood donors, 16 (1.4%) were positive for the antibody and none was Delta-antigen positive. In 130 patients with acute hepatitis, one (0.77%) was positive for anti-HDV, as well as three (2.22%) out of 135 patients with chronic active hepatitis (CAH), and three (5.77%) out of 52 patients with cirrhosis (C). No anti-HDV positive was found among seven fulminant hepatitis (FH) cases. The presence of HBeAg and anti-HBe was studied in anti-HDV positive sera; eleven (69%) volunteer blood donors were anti-HBe positive, and five (31%) were HBeAg positive. HBeAg was positive in the three CAH cases, and in one out of three C Cases with anti-HDV positive. Hepatitis Delta antigen was also positive in the hepatocytic nuclei in the three patients with C and two of the three CAH cases. The present results show that Delta infection is rare among blood donors in Argentina. A small variation without statistical significance could be found within different geographical areas. Among patients with HBsAg related liver disease, the presence of HDV markers was also low.

Adolescent↗
PubMed1987

Hepatitis A virus in stool during clinical relapse.

Among 256 patients with acute hepatitis A, 17 (6.6%) had a relapse of the disease between 30 and 90 days after the primary episode. We studied 7 of these patients. Serologic testing showed mean alanine aminotransferase levels of 1668 IU/L during the acute stage, 107 IU/L during the early convalescence, and 1027 IU/L during the relapse. Tests for IgM antibody against hepatitis A virus were positive in the 7 patients at the onset of disease, with decreasing levels in 3 of the 4 patients tested during the evolution of the illness. Stools collected during the relapse phase showed hepatitis A virus by immune electron microscopy, radioimmunoassay, and molecular hybridization using a 32P-labeled cDNA-hepatitis A virus probe. Stools collected from 4 of these patients 6 to 12 months after the onset of disease were negative for the virus. The finding of hepatitis A virus in the stool of these patients during the relapse phase strongly implicates hepatitis A virus as the causative agent of the clinical relapse.

Adolescent↗
PubMed1983

[Immune response to the vaccine (Hepavax B) against the B virus].

40 volunteers were vaccinated with a vaccine against hepatitis B (Hepavex B). All vaccines were at high risk to develop hepatitis B. After the third dose 37 (92.5%) of the vaccines, developed antibodies (HBsAb). The group more exposed to the virus B developed antibodies earlier, after the first dose. It is especulated that the earlier response could be anamnestic, due to previous inaparent contact with B virus. There were not serius side effects due to the vaccination.

Adult↗
PubMed1982

[Determination of cholic and sulfolithocholic acids in various hepatopathies].

The conjugated cholic acid (glycocholic acid) (GC) in the serum and the conjugated sulfolithocholic acid (sulfolithoglycocholic acid (SLGC) in 35 aggressive chronic hepatitis (HCA), 22 cirrhosis, 11 primary biliary cirrhosis (CBP), 11 pruritus of pregnancy and in 20 normal controls were determined. The control group revealed a mean value of GC of 21 micrograms % with a dispersion of +/- 14 micrograms % and for SLGC of 36 micrograms % with a dispersion of +/- 9 micrograms %. The frequency of the alteration of GC and SLGC in the cases of chronic hepatitis was low (14% and 9%) as well as in the cirrhosis (23% and 14%). In the pruritus of pregnancy the values reached 64% and 45%. On the other hand, the values were significantly elevated in CBP (100% and 90%) (p.001 and p.006). The absolute values in the various pathologies revealed mean values which were different but with a very wide dispersion that prevented us from seeing any relation between those absolute values and the different diseases. The alteration in the metabolism of biliary acids in the hepatic pathology was manifested by the postprandial determination of GC and SLGC in 20 HCA in whom the frequency of abnormal values rose from 14% and 9% on fasting to 60% and 45% prandially.

Chronic Disease↗
PubMed1982

[Immunosuppressive treatment of patients with chronic active HBsAg positive hepatitis].

Sixty four CAH type B patients were studied, they were simultaneously treated with corticosteroids and azathioprine for an average period of 52 months. The patients were classified into two groups: CAH without cirrhosis (45) and CAH with cirrhosis (19). Patients were initially treated with doses of 40 mg prednisone and 50 mg azathioprine. The reduction of steroids was done according to ASAT level; medication being discontinued when there were not signs of activity in liver biopsy. Therapy was readministered due to elevation of ASAT (5 fold) and the liver biopsy shown pattern of CAH. 49% of CAH patients without cirrhosis improve histology and discontinue treatment; half of them had to resume therapy because of relapse. 14% of the patients died (4); three of them belonging to the group who continued taking the drugs. In the CAH group with cirrhosis, 6 were in remission and withdrawn-from treatment, but 5 had to resume it. The mortality rate of this group was of 69% (13), all patients belonging to the group where were not able to discontinue medication. In both groups ASAT was a good parameter of activity. Complications were more frequent in the group with cirrhosis (42%) than in the one without cirrhosis (17%) (p less than 0.01). In patients with CAH type B, the best therapeutic response was associated to those cases without cirrhosis. Mortality rate is high in patients with cirrhosis at onset of therapy.

Adolescent↗
PubMed1980

[Incidence of HAV and HBc antibodies in patients with chronic hepatitis].

156 patients with chronic hepatitis were studied in Rosario, Argentina. 98 patients were HBsAg positive (group I) and 58 patients were negative (group II). 209 normal volunteer blood donors served as controls (group III). In all cases the presence of anti-HAV was sought by RIA and was found in 92% of cases in group I, 91% in group II and 82% in group II patients. In groups II and III we also determined the presence of anti-HBcAg by RIA being positive in 65% and 15% respectively (p less than 0.01). There were no differences related to sex, age and type of chronic hepatitis. We conclude, firstly that the percentage of anti-HAV is similar in chronic hepatitis and healthy controls; secondly, that 65% of patients with HBsAg negative chronic hepatitis have evidence of virus B infection demonstrated by the presence of anti-HBcAg; finally we remark the greater sensitivity of RIA over hemmagglutination for the detection of anti-HBcAg.

Age Factors↗