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Biomedical subjects

A Hurtado

Publications and source records attributed to A Hurtado.

At least 55 records · Page 3Linked to original sources
PubMed1994

Conservation of the cytotoxin-associated (cagA) gene of Helicobacter pylori and investigation of association with vacuolating-cytotoxin activity and gastroduodenal disease.

Polymerase chain reaction (PCR) amplification and DNA hybridization analyses were used to test for the presence of the cytotoxin-associated (cagA) gene in 108 strains of Helicobacter pylori. Fifty-two geographically diverse strains of known vacuolating cytotoxin activity, and 56 recent UK clinical isolates from patients with duodenal ulceration (n = 28) and from healthy individuals who were endoscopically normal (n = 28) were studied. Overall, cagA was detected by PCR in 74 (69%) strains and DNA hybridization provided evidence of gene homologues in a further eight strains. For 96% of the cytotoxin-producing strains and 46% of the non-cytotoxin producing strains, there was a close association either with presence or absence of cagA. At the genomic level, Southern blot DNA hybridization showed that cagA was probably present in a single copy in most of the H. pylori tested, and that HaeIII restriction site variation within and around the gene provided additional markers of diversity for the species. As 40% of the cagA containing strains did not produce an active cytotoxin, and no significant association between cagA presence and DU-disease was observed, we concluded that the presence of the cagA gene in H. pylori could not be used as a single reliable predictor of higher risk patients.

Antigens, Bacterial↗
PubMed1994

Identification of mixed genotypes in Helicobacter pylori from gastric biopsy tissue by analysis of urease gene polymorphisms.

PCR-RFLP analysis of the urease A and B genes was used to investigate the frequency that Helicobacter pylori from gastric biopsy comprised genotypically distinct strains. Seventy-five strains of H. pylori from 44 subjects from four geographically diverse locations were examined and 31 distinct urease gene profiles were identified. For most cultures, the totals of the RFLP sizes were within 4% of the 2.41-kb PCR product. Five strains were genomically more complex suggesting they contained a mixture of related genotypes. The validity of the test confirmed by analysis of a known strain mixture and of single colony picks from biopsy cultures. Urease gene PCR-RFLP profiling was shown to be more sensitive than ribotyping for determining the genotypic homogeneity of H. pylori.

Base Sequence↗
PubMed1994

Comparison of PCR-based restriction length polymorphism analysis of urease genes with rRNA gene profiling for monitoring Helicobacter pylori infections in patients on triple therapy.

Multiple isolates of Helicobacter pylori from antral biopsies of nine patients were examined by DNA fingerprinting. Analysis of rRNA gene patterns and HaeIII restriction fragment length polymorphism of PCR-amplified urease genes were compared and used to study colonization before and after failed triple therapy. H. pylori isolates from a single biopsy shared the same HaeIII DNA fingerprint regardless of the isolation method (plate or broth). DNA pattern types of paired strains of H. pylori were distinct between patients and were not grossly affected by treatment except for one patient with an altered strain type. H. pylori infections were generally associated with several subpopulations of strains, evident from the subtypic variation before and after treatment, detectable by both DNA fingerprinting methods. The urease gene patterns also provided evidence that some cultures of H. pylori probably contained a mixture of genomic subtypes. The study suggests that triple therapy has the effect either of inducing minor genomic variations or of changing the proportions of different subtypes of H. pylori. It was concluded that urease gene profiling provides a simple yet reliable method of establishing whether treatment failures are attributable to incomplete eradication of H. pylori.

Anti-Bacterial Agents↗
PubMed1993

[Cardiac tamponade as a presentation of primary hypothyroidism in a young woman].

Pericardial effusion (PE) as a hypothyroidism associated sign, is something that can be found with relative frequency; nevertheless, cardiac tamponade (CT) as the first sign of this disease may be considered exceptional especially in young patients. We report a 31 years old woman with clinical symptoms and signs of CT that in the forward workshop was diagnosed of primary hypothyroidism as cause of the CT. We shortly describe the case and review the literature, emphasizing the importance of the knowledge of CT trigger factors in myxedematous PE, as well as its usual benign evolution with hormonal treatment, without recurrences of the CT after pericardiocentesis is performed. This justify a conservative approach, in spite of the slow resolution of the PE what can take as long as 1.5 years.

Adult↗
PubMed1987

Dopaminergic modulation of aldosterone secretion in the normal menstrual cycle.

A group of eight normotensive female volunteers with regular menstrual cycles were studied during two menstrual cycles: a control cycle and one in which they received lisuride, a D1-D2 dopamine agonist (0.025 mg/8 hr). The following tests were performed in both halves of both cycles: 1) the response of prolactin (PRL) to thyrotropin-releasing hormone (TRH) administration; 2) the response of plasma renin activity (PRA) and plasma aldosterone (PA) to furosemide for 2 hours in the upright posture; and 3) the response of PRL, PRA, PA, plasma potassium (K), and cortisol (F) to metoclopramide administration. An increased response of PRL to TRH and PA to furosemide in the upright position and to metoclopramide were found in the luteal phase of the control study (p less than 0.05). After lisuride administration, in the interphase, differences in the responses of PRL to TRH and PA to furosemide in the upright position disappeared, whereas that of PA to metoclopramide increased further. We conclude that the increase of aldosterone normally observed during the luteal phase of the menstrual cycle is at least partly conditioned by diminished dopaminergic tone and that the response of aldosterone secretion to furosemide-induced sodium depletion and its response to metoclopramide stimulation may be modulated by two different types of dopamine receptors.

Adult↗
PubMed1986

Accuracy of one-piece castings, preceramic and postceramic soldering.

An investigation was conducted to evaluate the relative accuracy of one-piece castings of FPDs of three, four, and five units with those assembled by preceramic soldering and postceramic soldering. The preceramic soldered FPDs were subjected to six simulated porcelain firing cycles to assure a homogeneous sample. A total of 15 FPDs, five of each length, were evaluated for each test condition. A three-piece aluminum mold with stainless steel dies, which allowed for varying the length of the prosthesis, was used to fabricate the FPDs in 52% gold-palladium alloy. Marginal discrepancies of the castings on the dies were compared for the three test techniques. The mesiodistal length of the FPDs that were pre- and postsoldered were also measured at the occlusal and at the gingival margins and compared with the restorations before soldering.

Dental Casting Technique↗
PubMed1986

Effect of converting enzyme inhibitors in hypertensive patients with non-insulin-dependent diabetes mellitus.

The aim of this study was to evaluate the effect of captopril on carbohydrate metabolism in diabetic patients with essential arterial hypertension. Sixteen patients with non-insulin-dependent diabetes mellitus and hypertension were studied. Captopril was employed in different doses, and where patients receiving 100 mg/day remained hypertensive, hydrochlorothiazide 50 mg/day was added. Treatment was maintained for 90 days in 14 patients, 2 being excluded because of side effects. Basal blood pressure was normalized in 8 patients (57%) with captopril alone, and in 6 patients (43%) following the addition of hydrochlorothiazide. Basal glucose levels were not altered. Oral glucose tolerance tests performed during captopril treatment showed a lower glucose response, without changes in the insulin response. There was significant weight loss during the study. We conclude that captopril appears to be a safe treatment in essential hypertension associated with non-insulin-dependent diabetes mellitus, producing no deleterious effects on metabolic control.

Blood Glucose↗
PubMed1984

Dopaminergic modulation of aldosterone secretion: effect of sodium balance and postural changes.

The influence of an increased endogenous production of angiotensin II and of sodium homeostasis upon the response of plasma aldosterone to metoclopramide administration has been investigated in 5 normal volunteers. Our results show that the increase of plasma aldosterone after metoclopramide administration is independent of angiotensin II, ACTH and potassium, and that it increases even further due to the endogenous production of angiotensin II induced by postural changes. The state of sodium balance seems to influence the response of plasma aldosterone to metoclopramide administration as it occurs with other stimuli of aldosterone secretion.

Adrenocorticotropic Hormone↗
PubMed1980

Intrasellar granuloma. Case report.

A case of giant-cell granuloma of the pituitary in a 28-year-old woman is reported. Clinical complaints included headache and amenorrhea. Endocrinological studies showed hypopituitarism. X-ray films showed enlargement of the sella turcica.

Adult↗