PubMed Health⌕ Search

Biomedical subjects

I Torres

Publications and source records attributed to I Torres.

At least 37 records · Page 2Linked to original sources
PubMed1995

Community level cancer control in a Texas barrio: Part II--Base-line and preliminary outcome findings.

In a quasiexperimental demonstration study, screening rates for breast and cervical cancers were measured among Mexican-American women in selected areas of San Antonio and Houston, Tex. This research was primarily designed to evaluate a cancer-screening promotion program in San Antonio by comparing changes in screening rates in panels from the two barrio communities. In a base-line population survey, we found a small, but significant, proportion of women (10%-15%) lacking Pap smears and a larger proportion (30%-40%) lacking mammography. In a panel study following women who lacked screening at base line, there was a trend toward greater Pap smear use among younger women and a significant increase in mammography for all age groups in San Antonio compared with groups in Houston. Although there was a difference in language use between the communities, rates of newly initiated screening within the communities were similar among monolingual Spanish speakers and among those who used English, supporting the hypothesis that the program increased both groups' participation in breast-cancer screening.

Adult↗
PubMed1995

Changes in the analgesic effects of mianserin associated with altered plasma protein binding in experimental cancer.

In a group of mice bearing experimentally induced tumors, the protein binding of mianserin in vitro was measured and compared with a control group. The analgesic effect and the brain uptake of drug was also compared with a control group after an intraperitoneal dose of mianserin. The unbound percentage of mianserin in the plasma of mice with experimental cancer decreased with respect to control animals (5.20 +/- 0.12 vs 6.06 +/- 0.26; p<0.05) and alpha1-acid glycoprotein (AAG) levels, measured as plasma mucoprotein concentrations, were significantly increased (p<0.05). The brain/plasma drug concentration ratio of mianserin decreased in mice with experimental cancer when compared with control mice (1.11 +/- 0.03 vs 1.42 +/- 0.10; p<0.02). In both groups of mice, the mianserin analgesic effect was evaluated by the hot plate test after intraperitoneal drug administration. When the analgesia response-dose curve (0-60 mg/kg) was studied, a significant decrease in the response in mice with experimental cancer versus control mice was observed. These results suggest that resistance to the mianserin analgesic response may occur in animals with cancer disease. This resistance may be associated, in part, with an altered plasma protein binding, but other mechanisms could be involved.

Analgesics↗
PubMed1994

One-minute exposure of 4-cell mouse embryos to glucose overcomes morula block in CZB medium.

One-cell mouse embryos that block at the 2-cell stage can progress to the morula stage in CZB medium, but fail to cavitate and then swell and lyse. A 1-min exposure to 27 mM glucose at the 4-cell stage (approximately 42 hr) will support a high frequency of development to the blastocyst stage (75%) in the same medium. A glucose exposure is beneficial anytime between 30 and 54 hr of culture (67-73% blastocysts). Of a group of additional sugars and glucose analogues tested for their ability to replace glucose, only galactose was equivalent in promoting embryo development to the blastocyst stage (64% blastocysts).

Animals↗
PubMed1992

Influence of changes in protein binding on the central activity of antidepressants.

The central effect (expressed as analgesic response), protein binding and brain uptake of mianserin were measured in mice receiving drug intraperitoneally. A significant decrease of the central effect of mianserin (30 mg kg-1) was seen in mice with experimental inflammation when compared with control animals (reaction time (s) = 12.12 +/- 1.22 vs 25.56 +/- 2.92; P less than 0.001) and the dose-analgesia response curve (10-60 mg kg-1) was significantly shifted to the right in mice with inflammation. In serum of mice with inflammation, unbound concentration of mianserin was decreased from 19.37 +/- 0.73 to 17.83 +/- 0.30% (P less than 0.05) and seromucoid levels were significantly increased (P less than 0.001). Following the intraperitoneal administration of 30 mg kg-1 of mianserin, brain uptake decreased in diseased mice when compared with control animals (P less than 0.02), suggesting that the decrease in analgesia was secondary to a decrease in drug delivery to the brain because of increased protein binding.

Animals↗
PubMed1990

Development of 1-cell embryos from different strains of mice in CZB medium.

One-cell embryos from several different strains of mice have been cultured to the blastocyst stage in CZB medium. CZB medium can be used to culture CF1 x B6SJLF1/J 1-cell embryos to the blastocyst stage provided glucose is introduced into the medium on Day 3 of culture. The amount of glucose required for embryo development was titrated using a concentration range of 5.5 to 49.5 mM. With the exception of the highest concentration, all glucose levels tested supported 65-85% development to the morula and blastocyst stages. Variations of CZB medium were tested for their ability to support the development of 1-cell embryos from 4 strains of mice. For embryos from CF1 and DBA/2J (both x B6SJLF1/J) mice, which exhibit a "2-cell block" to development in vitro, CZB medium containing glutamine with the addition of glucose on Day 3 supported optimum development from the 1-cell stage to morula and blastocysts (79% and 87%). For embryos from B6D2F1/J and CD1 female mice (both x B6SJLF1/J males), which do not exhibit a "2-cell block" to in vitro development, optimum development to morula and blastocyst stages (95% and 50%) was in CZB medium containing both glutamine and glucose from the start of culture.

Animals↗
PubMed1990

A highly fluorescent simultaneous azo dye technique for demonstration of nonspecific alkaline phosphatase activity.

We describe a fluorescent histochemical technique for detection of nonspecific alkaline phosphatase (APase) in cells. The technique utilizes standard azo dye chemistry with naphthol AS-MX phosphate as substrate and fast red TR as the diazonium salt. The reaction product is a highly fluorescent red precipitate. Pre-implantation mouse embryos were used to establish optimal fixation and staining protocols and the specificity and sensitivity of the method. Fixation was in 4% paraformaldehyde for 1 hr, as glutaraldehyde induced autofluorescence of the cells. Maximal discriminable staining was detected after 15-20 min in the stain solution. The stain solution itself proved to be non-fluorescent, thus allowing visual observation of the progress of the staining reaction by fluorescence microscopy in its presence. To test the specificity of this fluorescent APase stain, a variety of cell types of known APase reactivity were stained by this protocol. Mouse lymphocytes and STO fibroblasts were negative, whereas F9 teratocarcinoma cells, intestinal epithelial cells, and rat fetal primordial germ cells were all found to be highly positive for APase activity, in agreement with published results on APase localization in these cells.

Alkaline Phosphatase↗
PubMed1989

An improved culture medium supports development of random-bred 1-cell mouse embryos in vitro.

One-cell CF-1 x B6SJLF1/J embryos, which usually exhibit a 2-cell block to development in vitro, have been cultured to the blastocyst stage using CZB medium and a glucose washing procedure. CZB medium is a further modification of modified BMOC-2 containing an increased lactate/pyruvate ratio of 116, 1 mM-glutamine and 0.1 mM-EDTA but lacking glucose. Continuous culture of one-cell embryos in CZB medium allowed 83% of embryos to develop beyond the 2-cell stage of which 63% were morulae at 72 h of culture, but blastocysts did not develop. However, washing embryos into CZB medium containing glucose after 48 h of culture (3-4-cell stage) was sufficient to allow development to proceed, with 48% of embryos reaching the blastocyst stage by 96 h of culture. Exposure of embryos to glucose was only necessary from the 3-4-cell stage through the early morula stage since washing back into medium CZB without glucose at 72 h of culture still promoted the development of 50% of embryos to the blastocyst stage. The presence of glucose in this medium for the first 48 h of culture (1-cell to 4-cell stage) was detrimental to embryo development. Glutamine, however, exerted a beneficial effect on embryo development from the 1-cell to the 4-cell stage although its presence was not required for development to proceed during the final 48 h of culture. Blastocysts which developed under optimum conditions contained an average of 33.7 total cells. The in-vitro development of 1-cell embryos beyond the 2-cell stage in response to the removal of glucose and the addition of glutamine to the culture medium suggests that glucose may block some essential metabolic process, and that glutamine may be a preferred energy substrate during early development for these mouse embryos.

Animals↗
PubMed1987

Evaluation of 2 intravenous thrombolytic agents (anisoylated plasminogen streptokinase activator complex versus streptokinase) in patients with acute myocardial infarction.

Ten patients with symptoms of acute myocardial infarction of less than 6 hours duration were randomised to receive either anisoylated plasminogen streptokinase activator complex [APSAC] (30U) or streptokinase (1,500,000U) intravenously. The aims of the study were to compare the angiographic patency of the infarct-related coronary arteries and to monitor drug safety and tolerance for up to 24 hours. The left anterior descending artery was occluded in 3, the left circumflex in 3 and right coronary artery in 4 patients. Time between onset of pain and treatment ranged from 150 to 330 minutes. At 90 minutes, 8 patients, 3 of 5 (60%) of the APSAC group and all of the streptokinase group, had patent arteries. No significant differences were found in measurements of coagulation. There were no haemorrhagic complications. One patient of the APSAC group had reinfarction 6 hours after treatment and died in cardiogenic shock. APSAC seems safe and is easier to use than streptokinase, and both agents result in patency in the majority of patients, although too few patients were included to allow a valid comparison. However, thrombolysis should be considered only a temporary solution in acute myocardial infarction, associated mainly with 3-vessel disease.

Aged↗
PubMed1986

An experimental approach to language training in second language acquisition: Focus on negation.

The effect of negation training in a second language on the expression of negation in the native language was investigated. Four-year-old children from bilingual (Spanish/English) homes who showed no expressive or receptive ability in Spanish negation and were either proficient or nonproficient in English negation received Spanish negation training. Children who were proficient in English negation maintained correct responses in English and showed increased correct responses in Spanish following simultaneous training in both languages or in Spanish alone. Children who were nonproficient in English negation demonstrated a decrease in correct English responses following training in Spanish alone; however, children who received training in English and Spanish simultaneously showed increases in correct responses in both languages. These findings suggest that language training programs with children learning a second language should consider the relationship of the two language training conditions (simultaneous vs. independent) with the child's level of native language proficiency.

Journal Article↗
PubMed1982

Evidence for a modulatory role of catecholamines on hypothalamic somatostatin in the rat.

The influence of catecholamines (CA) on hypothalamic somatostatin (HPT-SRIF) was investigated in rats by using several drugs which interfere with brain CA metabolism. Depletion of brain CA stores by alpha-methyl-rho-tyrosine (AMT) increased HPT-SRIF, while augmented brain CA levels following L-dopa administration decreased HPT-SRIF content. Blockade of dopamine beta-hydroxylase activity by disulfiram depleted brain noradrenaline (NA) and decreased HPT-SRIF. The selective increase in brain NA stores caused by threo-dihydroxyphenylserine (DOPS) also produced an increase in HPT-SRIF. Increased dopamine (DA) and decreased NA levels after disulfiram + L-dopa (1 h) treatment did not modify HPT-SRIF, whereas unaltered NA and greatly increased DA levels following disulfiram + L-dopa (2 h) treatment produced a drastic reduction of HPT-SRIF. The results suggest that DA and NA exert an influence on HPT-SRIF, supporting previous observations.

Animals↗