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Biomedical subjects

E Sierra

Publications and source records attributed to E Sierra.

At least 19 recordsLinked to original sources
PubMed2006

A functional variant in the CD209 promoter is associated with DQ2-negative celiac disease in the Spanish population.

AIM: To address the role of CD209 in celiac disease (CD) patients. Non-human leukocyte antigen (HLA) genetic factors in CD predisposition are poorly understood, and environmental factors like infectious pathogens may play a role. CD209 is a dendritic and macrophage surface molecule involved in pathogen recognition and immune activation. Recently, a functional variant in the promoter of the CD209 gene (-336A/G) has been shown to affect the transcriptional CD209 activity in vitro and it has been associated with a higher susceptibility to/or severity of infection. METHODS: The study population was composed of two case-control cohorts of 103 and 386 CD patients and 312 y 419 healthy controls as well as a panel of 257 celiac families. Genotyping for the -336A/G CD209 promoter polymorphism was performed using a TaqMan 5' allelic discrimination assay. HLA-DQ was determined by hybridization with allele specific probes. RESULTS: Initially, the case-control and familial studies did not find any association of the -336 A/G CD209 genetic variant with CD susceptibility. However, the stratification by HLA-DQ2 did reveal a significant association of CD209 promoter polymorphism in the HLA-DQ2 (-) group (carrier A vs GG in DQ2 (-) vs DQ2 (+) patients (P = 0.026, OR = 3.71). CONCLUSION: The -336G CD209 allele seems to be involved in CD susceptibility in HLA-DQ2 (-) patients. Our results might suggest a possible role of pathogens in the onset of a minor group of CD patients.

Alleles↗
PubMed2006

Tobacco use in the Dominican Republic: understanding the culture first.

OBJECTIVE: To conduct formative research on the landscape of tobacco use to guide survey and subsequent intervention development in the Dominican Republic (DR). DESIGN: Rapid Assessment Procedures, systematic qualitative methods (participant-observations, in-depth interviewing, focus groups) using bilingual mixed age and gendered teams from the United States and DR. SUBJECTS: Over 160 adults (men and women), ages 18 to 90 years, current, former and never smokers, community members and leaders from six underserved, economically disadvantaged DR communities. MAIN OUTCOME MEASURES: Key domains: tobacco use patterns and attitudes; factors affecting smoking initiation, continuation, quitting; perceived risks/benefits/effects of smoking; and awareness/effects of advertising/regulations. RESULTS: Perceptions of prevalence varied widely. While "everybody" smokes, smokers or ex-smokers were sometimes difficult to find. Knowledge of health risks was limited to the newly mandated statement "Fumar es prejudicial para la salud" [Smoking is harmful to your health]. Smokers started due to parents, peers, learned lifestyle, fashion or as something to do. Smoking served as an escape, relaxation or diversion. Quit attempts relied on personal will, primarily for religious or medical reasons. Social smoking (custom or habit) (< 10 cigarettes per day) was viewed as a lifestyle choice rather than a vice or addiction. Out of respect, smokers selected where they smoked and around whom. Health care providers typically were reactive relative to tobacco cessation, focusing on individuals with smoking related conditions. Tobacco advertising was virtually ubiquitous. Anti-tobacco messages were effectively absent. Cultures of smoking and not smoking coexisted absent a culture of quitting. CONCLUSIONS: Systematic qualitative methods provided pertinent information about tobacco attitudes and use to guide subsequent project steps. Integrating qualitative then quantitative research can be replicated in similar countries that lack empirical data on the cultural dimensions of tobacco use.

Adolescent↗
PubMed2005

Virulence factors and pathogenicity of Hafnia alvei for gilthead seabream, Sparus aurata L.

Virulence factors (eae gene, haemolytic capacity, fimbriae, resistance to the bactericidal effect of serum, siderophore production) and pathogenicity for gilthead seabream, Sparus aurata L., were analysed for 23 Hafnia alvei strains. None of the strains used in LD50 studies were lethal for seabream at doses as high as >10(8) cfu mL(-1). In chronic challenge studies differences in severity of the inflammatory response were observed between strains. On the basis of correlation of the inflammatory response to different strains of H. alvei in seabream with those virulence factors studied, it was only possible to establish a positive correlation between pathogenicity and resistance to the bactericidal effect of fish serum. Gilthead seabream is thus a species with considerable resistance to experimental infection with H. alvei. The bacterium does, however, have the capacity to remain viable in seabream for up to 3 months, without any clinical signs. Hafnia alvei is a well-recognized human and animal pathogen. Thus, as the pathogen can coexist with aquaculture operations, cultured gilthead seabream could represent a risk to human health as a carrier in some circumstances.

Adhesins, Bacterial↗
PubMed2004

Estimation of HIV incidence among repeat anonymous testers in Catalonia, Spain.

A retrospective cohort study of 2124 repeat HIV testers attending at anonymous testing sites (ATS) of Catalonia between 1995 and 2001 registered 3273 person-years (PY) of follow-up and 76 seroconversions (incidence density of 2.32 per 100 PY; 95% CI: 1.83, 2.90). The highest HIV infection incidence was observed among heterosexual injection drug users (IDU) (9.25 per 100 PY; 95% CI: 6.77, 12.25) and the lowest was among heterosexual non-IDU (0.69 per 100 PY; 95% CI: 0.35, 1.24). In multivariate Cox regression, factors independently associated with seroconversion were men having sex with men, IDU, and having sex with a known HIV-infected person. In spite of some limitations, such results suggest that prevention interventions targeting specific groups attending at ATS in Catalonia should be prioritized.

AIDS Serodiagnosis↗
PubMed2003

Case report: esophageal collision tumor (oat cell carcinoma and adenocarcinoma) in Barrett's esophagus: immunohistochemical, electron microscopy and LOH analysis.

We report a case of an esophageal collision tumor composed of adenocarcinoma and oat cell carcinoma. Both tumors appeared to arise from dysplastic Barrett's mucosae in a 75-year-old man. Immunohistochemical stains and electron microscopy demonstrated a separate identity for each of the tumors in collision. Molecular analysis of microsatellite regions was performed in different microdissected areas. Identical loss of heterozygosity (LOH) at 9p21 and 17p13 was determined in the three different microdissected areas of the adenocarcinoma component. LOH was not determined in any area of the oat cell carcinoma. This is the first study that analyzes the allele status of an esophageal collision tumor. Our findings suggest a biclonal origin for both components of the collision tumor.

Adenocarcinoma↗
PubMed2003

3p21, 5q21, 9p21 and 17p13 allelic deletions accumulate in the dysplastic spectrum of laryngeal carcinogenesis and precede malignant transformation.

A tissue field of somatic genetic alterations precede the histopathological phenotypic changes of carcinoma. Loss of Heterozygosity (LOH) at the sites of known or putative tumor suppressor genes is a common genetic abnormality detected in precancerous conditions. These genomic changes could be of potential use in the diagnosis and prognosis of pre-malignant laryngeal lesions. Recently the concept of laryngeal intraepithelial neoplasia (LIN) was introduced. To evaluate patients with an increased risk of developing invasive laryngeal carcinoma via a dysplasia-carcinoma progression we investigated 102 microdissected cell populations. Cell populations were procured from 15 laryngectomy specimens with different peritumoral histological changes adjacent to the squamous cell carcinoma cells and 15 laryngeal endoscopic biopsies with no evidence of malignant transformation in a 6-10-year follow-up period. Histological diagnoses were subdivided into keratosis without dysplasia (KWD), with mild dysplasia (LIN 1), with moderate dysplasia (LIN 2), and with severe dysplasia or carcinoma in situ (LIN 3). Microsatellite analysis was performed with the aim of studying LOH of 5q21 (APC), 9p21 (p16), 3p21 and 17p13 (p53) chromosomal regions. Frequent allelic losses were found in carcinoma cells at p53 (54%), p16 (66%), 3p21(87%) and 5q21(58%). Identical LOH patterns were determined in 100% of the LIN3 peritumoral cells, 60% of LIN2, 50% of LIN 1 and 25% of KWD. In contrast, histologically normal mucosae, KWD and LIN1 lesions without malignant progression showed no allelic loss. These results show that dysplasia correlates with LOH at 3p21, 5q21, 9p21 and 17p13 in early laryngeal carcinogenesis. These genomic changes in pre-malignant laryngeal lesions could be of potential use as markers for cancer risk assessment.

Adult↗
PubMed2001

Optimization of the technique to isolate fetal hepatocytes, and assessment of their functionality by transplantation.

In contrast to adult hepatocytes, fetal hepatocytes (FH) are thought to be highly proliferative less immunogenic and more resistant to both cryopreservation and ischemic injury. In the present study, we describe the method for isolation of FH and the relationship between the transplantability of FH into the spleen of analbuminemic rats and expression of albumin mRNA. Rat FH were obtained using the nonperfusion collagenase/DNase digestion method. Nagase analbuminemic rats (NAR), a strain which bears a mutation that determines the impossibility of the normal splicing of the albumin mRNA were used as recipients. The transplanted FH immediately migrated to the liver via portal vein, and anchored there. To assess the functional state of the transplanted cells, one month after transplantation, the expression of the albumin gene was studied in the liver of the recipients.

Adenosine Triphosphate↗
PubMed2001

3p21, 5q21, and 9p21 allelic deletions are frequently found in normal bronchial cells adjacent to non-small-cell lung cancer, while they are unusual in patients with no evidence of malignancy.

Molecular cytogenetic and loss of heterozygosity (LOH) analyses of non-small-cell lung cancer (NSCLC) have shown frequent allelic deletions in a variety of chromosomes, such as 1p, 3p, 5q, 8p, 9p, 11p, 11q, and 17p. Allelic loss at 3p21, 9p21, and 5q21 has also been reported in premalignant epithelial lesions of the bronchus and in normal bronchial cells. These findings suggest that a tissue field of somatic genetic alterations precedes the histopathological phenotypic changes of carcinoma. LOH at chromosomal regions 3p21, 5q21, 9p21, and 17p (TP53) was looked for in the peritumoural normal bronchial cells from 30 archival surgically resected tumours. Microdissected normal bronchial cells from 20 benign cytological smears were also added to the study. Matched populations of lymphocytes, tumour cells, and normal bronchial cells adjacent to the tumour were microdissected from paraffin-embedded tissues, while matched populations of normal bronchial cells and inflammatory cells were microdissected from benign cytological smears (bronchial brushings). Polymerase chain reaction (PCR) amplification was performed utilizing the specific markers D5S346, D3S1300, D9S157, D9S171, and TP53. Within the NSCLC tumour cells, LOH was more frequently found at the 5q21 locus (72% of the informative cases), the 3p21 locus (47%), 9p21 (48%), and 17p (33%). Within the peritumoural normal bronchial cells, LOH at 5q21 was found in 37.5% of the cases, 22% showed LOH at 3p21, 27% at 9p21, and 13% at 17p (TP53). LOH was also detected in one case, in normal bronchial cells obtained from cytological smears at one locus (5q21). In conclusion, normal bronchial mucosa adjacent to NSCLC has frequent allelic losses at 3p21, 5q21, and 9p21, while LOH at these loci is unusual in normal bronchial cells obtained from cytological smears from patients with no evidence of malignancy. LOH at these loci may be present before the onset of the malignant growth. LOH studies may supplement the histopathological evaluation of bronchial cells to detect genotypic alterations in both cytological and biopsy specimens.

Adult↗
PubMed2001

Environmental risk factors and Crohn's disease: a population-based, case-control study in Spain.

BACKGROUND: The pathogenesis of inflammatory bowel disease probably involves an interaction between genetic and environmental factors: cigarette smoking, appendectomy and oral contraceptives have been the factors most frequently linked to its aetiology AIM: To analyse the association between known environmental risk factors and development of Crohn's disease in the community of Aragón, Spain. PATIENTS AND METHODS: A case-control, population-based study has been carried out. All patients diagnosed with Crohn's disease in the community of Aragón from 1st February 1992 to 31st January 1995 were prospectively included. The Lennard Jones criteria were used to define the cases and selected controls among the healthy population matched with patients for age, sex and rural/urban habitat. Statistical analysis included multivariate analysis using conditional logistic regression, testing 38 different models. RESULTS: A total of 103 patients were diagnosed with Crohn's disease in Aragón from 1st February, 1992 to 31st January, 1995. Of these 62 patients (60.2%) with Crohn's disease were smokers, compared with 42 (40.8%) controls (p<0.001). Cigarette smoking is considered a risk factor for Crohn's disease with an odds ratio of 3.09 (95% confidence interval, 1.58-6.05). After multivariate analysis, the positive association is maintained. A dose-dependent relation could not be demonstrated. No statistical differences (p=0.50) were detected in the analysis of previous appendectomy. Use of oral contraceptive acts as a risk factor with a p=0.048; odds ratio 2, 8, 95% confidence interval: 1.009-7.774; but this association disappears in the multivariate analysis. Eight patients had a family history (3 first degree and 5 second degree relatives) versus none of the controls (p=0.002). Of the variables studied for childhood hygiene none appeared significant. CONCLUSION: Smoking, family history, and oral contraceptive use, appear as risk factors for developing Crohn's disease in univariate analysis, but only smoking remains significant in all models of multivariate analysis.

Adolescent↗
PubMed2001

[Cutaneous horn of the penis].

OBJECTIVE: To describe a case of cutaneous horn of the penis and review its clinical and histological features. METHODS: The clinical and histological features of cutaneous horn of the penis are described. RESULTS/CONCLUSIONS: Cutaneous horn of the penis is an uncommon lesion that is diagnosed without difficulty. Treatment is by surgery with sufficient margins due to its possible association with malignant lesions.

Aged↗
PubMed2000

[High eradication rates in Helicobacter pylori infection in patients with duodenal ulcer who failed previous eradication therapy].

BACKGROUND: To analyze the effectiveness of a second-line treatment of Helicobacter pylori infection in patients with duodenal ulcer based on previous antibiotic regimen. PATIENTS AND METHODS: Open, prospective, uncontrolled study, but guided by protocol including 30 consecutive patients with endoscopic diagnosis of active duodenal ulcer and failure of a first-line H. pylori eradication treatment diagnosed by urea breath test or a new endoscopy with histology and positive urease test. Treatment consisted in 10 days with omeprazole (20 mg/12 h), bismuth subcitrate (120 mg/6 h), tetracycline (500 mg/6 h) and metronidazole (500 mg/8 h) (OBTM) if previous regimen was with clarithromycin; or 10 days with omeprazole (20 mg/12 h), clarithromycin (500 mg/12 h) and amoxycillin (1g/12 h) (OCA) if previous regimen did not include clarithromycin; using metronidazole (500 mg/8 h) instead of amoxycillin (OCM) in case of allergy. Eradication was defined as a negative 13C-urea breath test 2 months after the end of therapy. RESULTS: One patient had to stop treatment due to the side effects and in 2 patients urea breath test was not performed (3 patients due to the OBTM group). Per protocol eradication was achieved in 25 out of 27 patients (92.6%) and by intention-to-treat eradication was attained in 25 out of 30 cases (83.3%). When both groups analyzed separately, the OCA combination was successful in 5 from 6 patients (83.3%; 95% CI 35.9-99.6); while the OBTM combination was successful in 20 from 21 valuable patients (95. 2%; 95% CI 76.2-99.9). In this second case we make an intention to treat analysis and eradication was achieved in 20 from 24 (83.3%; 95% CI 62.6-95.3). CONCLUSION: The eradicative treatment for H. pylori based in different antibiotics used in subsequent attempts get high eradication rates in patients with duodenal ulcer.

Adult↗
PubMed2000

Liver gene expression and increase in albumin synthesis by fetal hepatocytes transplanted into analbuminemic rats.

This report describes the evolution of hepatocytes isolated from 21-day fetuses and transplanted into spleens of Nagase analbuminemic rats which have negligible serum albumin levels due to a mutation affecting albumin mRNA processing. Albumin and alpha-fetoprotein expression, in addition to other parameters related to cellular proliferation status (thymidine kinase and proliferating cell nuclear antigen expression) were studied as indicative of the behavior and evolution of the cells. In recipient rats, only a few clusters of hepatocytes could be observed in the red pulp of the spleen 24 h after transplantation. The fetal hepatocytes migrated to the liver and could be seen in portal branches immediately after transplantation. Fifteen days later, albumin mRNA was detected in recipient livers and was expressed throughout the entire 3-month study. Alpha-fetoprotein was not detected. Cell proliferation was not relevant, although 3 months after transplantation, the proliferation rates appeared to show a tendency to increase. These data demonstrate that fetal hepatocytes transplanted into spleen migrate to liver, settle there and acquire an adult phenotype free of malignant transformation. Our study is a first step towards the thorough understanding of fetal hepatocyte transplantation. The next steps will involve in-depth studies of the possibilities of genetic manipulation to achieve a high degree of repopulation/expression, employing the least possible number of donor cells, and of how the cells reach the liver parenchyma, overcoming the endothelial barrier.

Albumins↗
PubMed2000

Factors affecting the variation in antibiotic resistance of Helicobacter pylori over a 3-year period.

Strains of Helicobacter pylori, isolated from 300 patients between 1996 and 2000 were tested for their sensitivity to clarithromycin, metronidazole and amoxycillin. Primary resistances (95% CI) were 9. 7% for clarithromycin and 21.7% for metronidazole. No strains were resistant to amoxycillin. There was no significant difference between the number of resistant strains in the male and female groups. Clarithromycin resistance was more common in older patients (P<0.01) and metronidazole resistance was more common in patients with peptic ulcer compared with patients with chronic gastritis (P<0. 05). Logistic regression analysis confirmed these results.

Adolescent↗
PubMed2000

Third line treatment for Helicobacter pylori: a prospective, culture-guided study in peptic ulcer patients.

BACKGROUND: A third line treatment is needed in roughly 5% of patients infected with Helicobacter pylori. Few data have been reported on efficacy of treatment regimens in these patients. METHODS: A prospective trial was designed to study the effectiveness of third line treatment of H. pylori infection in ulcer patients. Two-week quadruple, culture-guided, combinations were used in 31 consecutive patients. Susceptibility to metronidazole and clarithromycin were studied by E-test, and thereafter a predetermined treatment regimen was used. Compliance was evaluated by pill count, and eradication defined by negative urea breath test at 6 weeks. RESULTS: Two main quadruple regimens were used in 29 patients. In spite of good compliance, the combination of omeprazole, tetracycline, bismuth and clarithromycin (OTBC) showed an eradication rate (per protocol analysis) of 36% (five out of 14; CI: 12.8-64.9), and if amoxycillin was used (OTBA) the rate was 67% (eight out of 12; CI: 34.9-90.1). The difference was not significant. No clinical factor was found to be associated with failure to eradicate. CONCLUSIONS: Third line treatment often fails to eradicate H. pylori infection. New strategies need to be developed and tested for this common clinical situation.

Adult↗
PubMed2000

Comparative study of tumor angiogenesis and immunohistochemistry for p53, c-ErbB2, c-myc and EGFr as prognostic factors in gastric cancer.

Gastric cancer (GC) continues to be a highly aggressive malignancy with poor prognosis and low survival rates. The survival of patients with GC depends mainly on the stage of the disease, with early GC having a 5 year survival of 90-100% and advanced tumors a 5 year survival of 15-25%. The role of other prognostic factors in these tumors is still under investigation. 28 gastric dysplasia, 45 Early GC and 98 Advanced Gastric Cancers were evaluated for expression of the oncogenes p53, c-ErbB2, c-myc and the EGFr in paraffin-embedded material utilizing Avidin-Biotin immunohistochemistry techniques. In 34 cases of GC microvessel density (MVD) was determined in CD34 stained sections. Statistical correlations with stage, histologic type, differentiation degree, location, size, ploidy patterns and overall survival were done. The Mantel-Cox test was performed to evaluate which factors had an independent prognostic value. Both, tumor angiogenesis and p53 protein expression were statistically associated (95% confidence intervals) with overall survival in patients with GC. p53 protein expression was also correlated with cardial location, nodal involvement and tumor stage. c-ErbB2 may recognize a group of highly aggressive well differentiated adenocarcinomas with worse prognosis. c-myc was also significantly enhanced in well differentiated tumors. EGFr showed no significant associations. Mantel-Cox was performed to compare the prognostic value of tumor stage, p53 protein expression and tumor angiogenesis. Tumor angiogenesis was the most important prognostic indicator to predict overall survival in our series. p53 expression was not independent and did not provide additional prognostic information to tumor stage. Our study suggests that angiogenesis as demonstrated by microvessel counts in CD34 stained sections is a significantly important prognostic factor for predicting survival in gastric cancer.

Adult↗
PubMed1997

[Central venous catheter location by endocavitary ECG: an alternative to chest radiography].

BACKGROUND: The location of a central venous catheter is checked with a chest radiograph. Right endocavitary electrocardiography (ECG), a technique in which the catheter is connected to the ECG recorder wire to record ECG in DII, might be an alternate method to check the position of the catheter. When the catheter enters the right atrium, there is a large increase in the amplitude of P wave. The aim of this study was to compare the efficacy of endocavitary ECG against the chest radiography as a method to check the position of a central catheter, and to determine whether the ECG method can replace the radiological method. MATERIAL AND METHODS: One-hundred central catheters which location was checked by ECG and by chest X-ray entered the study. Efficacy of endocavitary ECG, delay between catheter insertion and radiological check, and the cost of the two methods were studied. RESULTS: Endocavitary ECG determined that de catheter was in a correct position in 80 cases and malpositioned in 20 cases. ECG check agreed with radiological check in 93 catheters. There were 4 false-positive and 3 false-negative cases. The efficacy of endocavitary ECG was 93% (sensitivity: 82%; specificity: 81%; positive predictive rate: 95%; negative predictive rate: 85%). Catheter location was checked immediately on insertion by ECG in all cases, while radiological check was delayed 32 +/- 25 min in the emergency department and 68 +/- 206 min in the admitted patients. The cost of the ECG method was less than that of the radiological method. CONCLUSIONS: The check of the position of a central venous catheter by endocavitary ECG is taster, cheaper, and of similar efficacy to the radiological method. Endocavitary ECG can replace chest X-rays to check the position of the catheter in more than 90% of cases.

Catheterization, Central Venous↗