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J I Arenas

Publications and source records attributed to J I Arenas.

At least 73 records · Page 4Linked to original sources
PubMed1994

Heterosexual transmission of hepatitis C virus and the possible role of coexistent human immunodeficiency virus infection in the index case. A multicentre study of 423 pairings.

OBJECTIVES: To define the role that sexual transmission plays in the spread of hepatitis C virus (HCV) infection, and to examine the influence of coexistent human immunodeficiency virus (HIV) infection on this mode of transmission. DESIGN: A multicentre, seroprevalence study of anti-HCV performed in the stable heterosexual partners (SHP) of index cases reactive for anti-HCV. SETTING: Department of Internal Medicine and Section of Gastroenterology of three University Hospitals, Spain. SUBJECTS: A total of 423 stable heterosexual partners of index cases reactive for anti-HCV. This included a group of 142 intravenous drug users (IVDU), 120 of whom were coinfected with HIV. Additionally, 2886 first-time voluntary blood donors selected at random were included to compare the prevalence of anti-HCV. MAIN OUTCOME MEASURES: Serum samples were screened for anti-HCV by a commercially available, second-generation enzyme-linked immunoassay. Tests repeatedly reactive for anti-HCV were analysed by a four-antigen, recombinant immunoblot assay. Anti-HIV was tested by enzyme immunoassay and Western blot was used for confirmation of positive cases. RESULTS: The prevalence of anti-HCV, was 7.1% in SHP and 1.2% in random donors (P < 0.001). This prevalence was higher in SHP of index cases coinfected with HIV in comparison with that shown in the SHP of index cases only reactive for the anti-HCV (9.1 vs. 6.3%; P = 0.2), particularly when a younger and more homogeneous group such as the SHP of IVDU index cases was considered alone (9.2 vs. 0%; P = 0.1). However, the SHP of IVDU index cases coinfected with HIV were almost three times more likely to be infected with HIV than HCV (24.2 vs. 9.2%). CONCLUSIONS: These data suggest that HCV infection may be sexually transmitted but with low efficiency, and this could be increased in the presence of coexistent HIV infection in the index case.

Adolescent↗
PubMed1994

Intrafamilial spread of hepatitis C virus infection.

We assessed the prevalence of antibodies to hepatitis C virus (anti-HCV) among 401 household contacts of 161 persons with chronic hepatitis C (index patients). None of the index patients had antibodies against HIV. The overall prevalence of anti-HCV was 3.2% (2.5% in the absence of previous parenteral exposure). Sexual partners had a seroprevalence of 4.7% and non-sexual contacts, 2.5%. Among non-sexual contacts, parents showed the highest rate (4.2%). The mean duration of exposure in the anti-HCV-positive sexual partners was 17.3 +/- 8.5 years, vis-à-vis 9.2 +/- 7.4 years in the anti-HCV-negative sexual partners. We conclude that there is little risk of HCV infection through household contact. Although the form of transmission is not well identified, the duration of sexual activity suggests that the time needed to become infected is long.

Adult↗
PubMed1994

[Massive fecal impaction in a patient with osteogenesis imperfecta].

The case of a 22 year old male with massive faecal impaction and anorectal mechanical stenosis caused by multiples bone fractures and pelvic deformities secondary to imperfect osteogenesis is reported. The patient was treated with subtotal colectomy and permanent colostomy.

Adult↗
PubMed1993

[Primary vascular tumors of the liver. Analysis of a series of 20 cases].

Twenty patients with one or several primary hepatic vascular tumours were studied. Three of them had an angiosarcoma and the other seventeen had twenty nine hepatic haemangiomas. From these seventeen patients, six corresponded to a giant cavernomatous haemangioma. Symptoms, diagnostic methods and treatment of patients with angiosarcoma (3 cases), giant cavernomatous haemangioma (6 cases) and haemangiomas with size less than 4 cm (11 cases) are separately analyzed. We report our series and a critical revision of diagnosis and treatment of these tumours is made.

Adult↗
PubMed1992

[Dubin-Johnson syndrome. Presentation of 3 cases. Review of the national literature].

Three patients, two male and one female, 42, 64 and 20 years old respectively, with a Dubin-Johnson syndrome are reported. Both men referred jaundice since several years and in the woman's case, the onset of the illness took place during the last term of her second pregnancy. In two patients, liver aspect and it's biopsy were diagnostic. In the other, who was hospitalized because of a myocardial infarction, a hepatic gammagraphy with Tc 99 HIDA was made. No case was associated with biliary lithiasis and only one patient had other members in his family with the illness.

Adult↗
PubMed1991

Expression of type 1 blood group precursor in human gastric carcinoma.

The surface epithelium of normal gastric mucosa from patients with gastric adenocarcinoma expressed the type 1 blood group precursor only in Lewis (Le) non-secretor individuals, Le a+b- (se/se, Le/-) and Le a-b- (se/se, le/le). In secretors, the superficial mucosa was negative. Deep areas of the mucosa showed no type 1 precursor regardless of secretor status. Expression of type 1 precursor was anomalously found in neoplastic cells in 14 of 16 Le a-b+ (secretors) patients and in 4 of 5 Le a-b- (secretors) patients. The 1 Le a-b- non-secretor carcinoma expressed type 1 precursor strongly. 6 of 8 Le a+b- non-secretor carcinomas showed positivity for the monoclonal antibody K-21. Thus the type 1 precursor reacted with the non-neoplastic gastric surface of non-secretors but not with those of secretors, and also with most gastric adenocarcinoma regardless of secretor status and Lewis phenotype.

Adenocarcinoma↗
PubMed1990

Lewis system alterations in gastric carcinogenesis.

Alterations in the expression of type 1 blood group-related antigens (Lewis a and b) were examined immunohistochemically in 371 consecutives gastric biopsy and 80 surgical specimens from patients of gastric carcinoma. The ABH and Lewis phenotype and secretor status of the patients were correlated with histologic findings. An anomalous expression of Lewis a antigen was found in 88 of 249 gastric biopsy specimens of Lewis (a-b+) phenotype patients. The prevalence of this anomaly increased with the evolution of the premalignant process, in agreement with the commonly accepted model of gastric carcinogenesis. Thus, anomalous Lewis a antigen appeared in 66.6% of gastric dysplasia cases, in 64.6% of intestinal metaplasia, in 15.4% of atrophic gastritis, and in 7.4% of superficial gastritis. No alterations were found in subjects with normal gastric mucosa. Forty-seven of the 49 Lewis (a-b+) phenotype gastric carcinoma patients showed antigenic alterations in tumor cells (anomalous Lewis a antigen in 36 and loss of Lewis antigens in 11). In 26 of these gastric specimens an anomalous Lewis a antigen was present in areas of intestinal metaplasia and/or dysplasia away from the area of neoplastic transformation. The expression of Lewis a antigen in Lewis (a-b+) phenotype patients is a frequent phenomenon in gastric neoplastic cells and could result from the blocked synthesis of Lewis b antigen with accumulation of its precursors. These findings suggest that, during gastric carcinogenesis, antigenic alterations may precede neoplastic transformation. An anomalous Lewis a antigen could constitute a significant index of severity of the histologic lesion and contribute to identifying high-risk individuals.

Humans↗
PubMed1990

[Response to recombinant DNA antihepatitis B vaccine in mentally retarded patients with Down's syndrome. A controlled study].

To investigate the response of mentally retarded individuals (MR) with Down's syndrome (Down-MR) to recombinant hepatitis B vaccine, three doses (20 micrograms per dose) were administered on the usual schedule (months 0, 1 and 6) to two groups of MR with mean age of 14.6 years. The first group consisted of 32 MR-Down. The second group consisted of 35 MR other etiologies (non Down-MR). Both had the same sex distribution and similar ages and weight/height index. The post vaccination anti-HBs titers were measured on months 1, 2, 6 and 8. The results could be analysed in 63 MR. Eight months after vaccination, 100% of Down-MR and 91% of non Down-MR developed a response to the vaccine (anti-HBs greater than 10 IU/l). Both groups achieved high antibody titers (geometric mean 4.298 and 6.424, respectively). A significant inverse correlation of anti-HBs with age was found, but not with sex of with the weight-height index. It was concluded that Down-MR in young age have a normal response to recombinant hepatitis B vaccine at the usual dose and schedule. Therefore, the goal to suppress the reservoir of hepatitis B in Down-MR both in institutions for MR and in normal schools should be achieved.

Adolescent↗
PubMed1989

[Mentally deficient patients and infection caused by hepatitis B virus. Prevalence in our area].

To assess the prevalence of hepatitis B virus (HBV) infection in medium level mentally impaired patients (MIP), 620 MIP were evaluated; 181 of them had Down's syndrome and were active inmated of open institutions. At the time of the study, 28.7% had some positive serum marker of HBV infection, and 5.8% were virus carriers. The highest rate of seropositive individuals (48%) was found in male MIP with Down's syndrome. The rate of seropositive individuals was higher among those MIP who had attended special education centers than in those who had not. The tendency to remain as HBV carrier was higher in males with Down's syndrome. Our results confirm the need for prophylaxis in this population.

Adolescent↗
PubMed1989

Expression of type 1 and type 2 blood group-related antigens in normal and neoplastic gastric mucosa.

The distribution of the blood group-related antigens type 1 (Lewis(a) [Le(a)], Lewis(b) [Le(b)]) and type 2 (H type 2, Y) has been examined in histologically normal and malignant mucosa of 40 surgical specimens of patients with adenocarcinoma of the stomach, with the use of a panel of monoclonal antibodies. Patients' Lewis phenotype and secretor status are correlated to the authors' findings. The surface epithelium of normal pyloric and fundic mucosa expressed the Lewis isoantigen (Le(a) in Le[a+b-] phenotype and Le(b) in Le[a-b+] phenotype), whereas the deep areas of this mucosa no showed the Le(a), Le(b) antigens and expressed the Y and H type 2 antigens whatever the secretor status of patients. Nineteen of 24 patients with Le(a-b+) phenotype showed anomalous expression of Lea antigen in neoplastic cells. In three of them, this alteration was found in tumor adjacent mucosa. No expression of Le(a) or Le(b) antigens was found in tumors or normal mucosa from Le(a-b-) phenotype patients.

Antibodies, Monoclonal↗
PubMed1989

Expression of Lewis antigenic determinants in colorectal adenocarcinomas.

Expression of type 1 and type 2 chain Lewis antigens was studied in 32 rectal adenocarcinoma specimens; the results were correlated with the patients' Lewis phenotype and secretor status. In addition, the pattern of expression of these antigens was analyzed in adjacent and distant normal mucosa. We used an indirect immunofluorescence technique with p-phenylenediamine counterstaining (Oriol technique) and a panel of monoclonal antibodies directed against the different antigenic specificities. Normal distal colonic mucosa only expresses monofucosylated structures (Lea and X) arising from activity of the alpha 1-3,4-fucosyltransferase coded by the Le gene. Rectal adenocarcinomas also show Lea and X, but also reexpress blood group antigens ABH and exhibit difucosylated determinants (Leb and Y). The accumulation of mono- and difucosylated type 2 chain in neoplastic processes, independently of the Le and Se genes, could be due to the enzymes coded by reactivation of the H and X genes. Blood group antigens form a complex signal code, genetically regulated, which intervenes in differentiation, growth and cellular recognition processes, and which may undergo important modifications during malignant transformation. These alterations could be useful in the diagnosis and prognosis of some types of carcinoma.

Adenocarcinoma↗