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J Torres

Publications and source records attributed to J Torres.

At least 181 records · Page 10Linked to original sources
PubMed1991

Characterization of T- and B-cell epitopes of a simian retrovirus (SRV-2) envelope protein.

Synthetic envelope peptides of a simian retrovirus (SRV-2) were used to define both T- and B-cell epitopes of the envelope protein. The SRV-2 peptide 100-106 specifically blocks rhesus anti-SRV-2 neutralizing antibody activity, and a peptide 100-106 keyhole limpet hemocyanin conjugate induces a strong antipeptide antibody response. SRV-2 peptide 100-106 and 233-249 induces good T-cell proliferation of murine spleen cells immunized with the SRV-2 virus. Thus, SRV-2 envelope peptide 100-106 represents both a T- and B-cell epitope, and peptide 233-249 a T-cell epitope.

Amino Acid Sequence↗
PubMed1990

Linkage of two human pregnancy-specific beta 1-glycoprotein genes: one is associated with hydatidiform mole.

A genomic clone containing two linked human pregnancy-specific beta 1-glycoprotein (PS beta G) genes has been isolated and characterized. The two genes are arranged in the same 5'----3' orientation; the 3' region (including the A2 and B-C exons) of the upstream gene, PSGGA, is linked to the 5' region (including the 5'/L and L/N exons) of PSGGB, the downstream gene. Depending upon the domains compared, PSGGA and PSGGB share 92-98% nucleotide and 86-95% amino acid sequence identity with PSG93, the most abundant PS beta G transcript. The 3' exon (B-C) of PSGGA contains four alternative splice sites and three polyadenylylation sites, which account for the 3' heterogeneity previously reported in the PS beta G family. Each of the predicted PSGGA-encoded proteins would have a different carboxyl terminus. PSGGB corresponds to the previously identified cDNA PSG6, which encodes proteins containing a 34-amino acid leader peptide and a 108-amino acid N domain, which is one amino acid shorter than the majority of PS beta G N domains. Additionally, the PSGGB-encoded proteins contain the cell-surface recognition tripeptide Arg-Gly-Asp, shared by several previously reported PS beta Gs as deduced from cDNA sequences. Northern blot hybridization performed with a PSGGB-specific oligonucleotide probe to the N domain revealed that PSGGB or a PSGGB-like gene encodes a major 1.7-kilobase mRNA in hydatidiform mole tissues and a major 2.0-kilobase mRNA in term placenta tissues. Moreover, the PSGGB-specific probe hybridized most strongly with mRNA from molar trophoblastic tissue, suggesting that the PSGGB-like species may be the gene preferentially expressed in gestational trophoblastic disease. Additionally, the sequence of a 2315-base-pair PS beta G cDNA (PSG95) that contains an N-A1-A2-B2-C domain arrangement is reported. The coding region of PSG95 is identical to the previously reported cDNA clones PSG1d and FL-NCA, but PSG95 contains an additional 518 and 523 base pairs in the 3' end as compared with PSG1d and FL-NCA, respectively.

Amino Acid Sequence↗
PubMed1990

Enterotoxins from Clostridium difficile; diarrhoeogenic potency and morphological effects in the rat intestine.

The action of toxins A, B, and C from Clostridium difficile was studied in the small intestine and colon of rats. All three caused fluid accumulation in the small intestine, maximal secretion being induced by 1 micrograms of toxin A, 20 micrograms of B, and 15 micrograms of C. Both toxins A and C caused shedding of epithelial cells from the villi without visible damage to crypt cells; toxin A caused further extensive necrosis and bleeding. Toxin B caused secretion without visible damage to the epithelial cells, though this activity was unstable and decreased significantly after one week of storage. In the colon, toxin A caused secretion and shedding of surface epithelial cells without damage to crypt cells, toxin C caused only a weak secretion, and toxin B had no effect at all. In terms of immunohistochemistry, it was found that toxin A bound to the enterocytes at the tips of the villi but not to goblet and crypt cells. The complex expression or interaction of the toxins produced by Cl difficile may explain the broad spectrum of disease (diarrhoea, colitis, and pseudomembranous colitis) associated with this micro-organism.

Animals↗
PubMed1990

Pharmacologic treatment of noncognitive behavioral disturbances in elderly demented patients.

Fifty-nine elderly residents of long-term care facilities who had DSM-III diagnoses of dementia were studied in an 8-week randomized, double-blind comparison trial of haloperidol, oxazepam, and diphenhydramine to test the efficacy of these agents in the treatment of clinically significant behavioral disturbances in patients with dementia. All three agents demonstrated modest but significant efficacy as measured by clinician ratings of agitated behavior and activities of daily living. The absolute magnitude of improvement was greater for haloperidol and diphenhydramine than for oxazepam, but differences among groups did not approach statistical significance. Frequencies of acute adverse events during the trial were similar across the drug treatment groups. Although these drugs may differ in terms of long-term safety and efficacy, they appear to be equivalent for short-term management of agitated behavior in severely demented patients.

Activities of Daily Living↗
PubMed1989

Campylobacter jejuni chromosomal sequences that hybridize to Vibrio cholerae and Escherichia coli LT enterotoxin genes.

Campylobacter jejuni is one of the main etiologic agents of gastrointestinal illness in developing and developed areas throughout the world. Isolation of enterotoxin-producing C. jejuni has been associated with clinical symptoms of a watery-secretory type of diarrhea. Although physiological and immunological relatedness has been demonstrated between the C. jejuni enterotoxin (CJT), the Vibrio cholerae enterotoxin (CT), and the heat-labile cholera-like Escherichia coli enterotoxin (LT), nucleotide sequence similarity between C. jejuni DNA and either the toxA, toxB, eltA or eltB genes remained to be shown. We found that binding to ganglioside GM1 prevented recognition of CJT by monoclonal antibodies directed to either CT or LT. This indicates antigenic similarity between the three enterotoxins in the ganglioside GM1-binding site. Therefore we searched for corresponding similarities at the DNA level and found, by oligodeoxynucleotide hybridization, C. jejuni chromosomal nucleotide sequences similar to the coding region for a postulated ganglioside GM1-binding site on toxB and eltB.

Amino Acid Sequence↗
PubMed1989

Bacterial keratitis after radial keratotomy.

The authors identified nine patients with culture-proven keratitis after radial keratotomy (RK). Three patients became infected in the immediate post-operative period, and six patients had delayed-onset keratitis. Gram-negative rods were the predominant pathogens in late-onset keratitis (4 of 6 infections). Gram-positive cocci were implicated in all three postoperative infections. The inferior corneal quadrants were involved in seven of nine patients. Two episodes of late-onset keratitis were associated with contact lens wear. Five of these patients had transverse incisions or greater than eight radial cuts. All six patients regained visual acuity of 20/40 or better. Two additional cases of early-onset and six cases of late-onset keratitis with many features similar to these cases have been reported previously.

Adult↗
PubMed1988

2-Hydroxy-5-nitrobenzyl bromide as a specific reagent for tryptophan residues in membrane proteins: bacteriorhodopsin as an example.

The use of 2-hydroxy-5-nitrobenzyl bromide for the modification of tryptophan residues in integral membrane proteins is exemplified by its application to bacteriorhodopsin from Halobacterium halobium. Complete elimination of the unreacted reagent requires delipidation of the sample with detergents and posterior chromatography. This method also allows separation of the modified from the unmodified bacteriorhodopsin molecules. Modified molecules have lost the retinal, and are thus bleached, whereas the unmodified molecules appear to retain all the characteristics of solubilized native bacteriorhodopsin.

2-Hydroxy-5-nitrobenzyl Bromide↗
PubMed1988

Evaluation of the Dinamap continuous blood pressure monitor.

The validity of the Dinamap automated oscillometric blood pressure monitor, an instrument frequently used for continuous monitoring in intensive care settings, was evaluated in comparison to two standard methods of blood pressure measurement. Oscillometric monitoring was compared to random-zero sphygmomanometry in 28 ambulatory subjects, using the instruments in a random order. The oscillometric monitor overestimated random-zero systolic pressure (mean difference = 5.7 mm Hg; P less than 0.001), but did not differ in diastolic pressure (difference = 1.3 mm Hg, P greater than 0.3). Correlation (r) between methods was 0.94 for systolic pressure and 0.83 for diastolic pressure. Repeatability of sequential measures did not differ between methods. To evaluate the oscillometric monitor in the intraoperative setting, it was used simultaneously with a radial artery catheter to measure blood pressure in 14 patients undergoing peripheral vascular or other major surgery. The oscillometric monitor underestimated intra-arterial systolic pressure (mean difference = -9.4 mm Hg; P less than 0.002), but overestimated intraarterial diastolic pressure (difference = 5.7 mm Hg; P less than 0.005). There was no difference in mean arterial pressure (P greater than 0.1). Correlation between methods was 0.88 for systolic, 0.71 for diastolic, and 0.79 for mean arterial pressure. The oscillometric instrument had a sensitivity of 63% and specificity of 97% in detecting intraarterial systolic pressures of 160 mm Hg or greater, and a sensitivity of 89% and specificity of 89% in detecting intraarterial systolic pressures of 100 mm Hg or less. These findings demonstrate differences between the oscillometric monitor and other standard methods of blood pressure measurement.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗
PubMed1988

pH and H2O2 concentration of hydrogen peroxide disinfection systems.

Hydrogen peroxide disinfection has caused discomfort for some soft contact lens wearers even though the solution was neutralized properly. The discomfort could be due to the endpoint pH of the system used or the residual H2O2 concentration. Using a digital pH meter and H2O2 concentration detection strips, we measured the pH and H2O2 concentration of seven different hydrogen peroxide disinfection systems over their recommended disinfection and neutralization cycles to determine their time courses and endpoint values. The final pH of the seven systems varied from 6.15 to 7.74 pH units. All systems resulted in residual H2O2 concentrations below threshold values. These findings indicated that the final pH may be the cause of patient discomfort after hydrogen peroxide disinfection and neutralization.

Contact Lenses, Hydrophilic↗
PubMed1988

Hyperreactive malarial splenomegaly in Venezuela.

A cross-sectional seroepidemiological survey seeking hyperreactive malarial splenomegaly was carried out in isolated Yanomami hamlets in Amazonas Territory in Venezuela. All 110 inhabitants greater than 1 year of age were evaluated clinically and 98 were studied immunologically. The spleen index for individuals greater than 10 years of age was 44%. Only 3 patients had Plasmodium spp. on thick blood smears. All had serological evidence of infection with Plasmodium falciparum and P. vivax. Twenty-three patients were considered to show hyperreactive malarial splenomegaly. Clinical manifestations of the syndrome did not differ from those described in other parts of the world.

Adolescent↗
PubMed1987

Multicenter study with ketanserin in essential hypertension: an Argentine experiment.

One thousand eleven patients with essential hypertension (H) were evaluated upon compliance with the following inclusion criteria: (a) mild to moderate uncomplicated H, with supine diastolic blood pressure (Su DBP) greater than 90 mm Hg at the end of the placebo period, with or without antihypertensive treatment; (b) greater than 20 years old. The dosage of ketanserin (K) was 20 mg b.i.d. up to the fourth week. Afterwards, if the patients normalized, we continued with the same schedule. If this did not occur, the dosage was increased (40 mg b.i.d.) up to the eighth week. Four hundred fifty-one men and 560 women were included, with a mean age of 56.6 years, mean body weight 74.8 kg, and mean height 166.30 cm. At the end of the eighth week, the percentage of normalization was 75.5% of the patients, and the percentage of partial responders was 5.6%. The decrease of the blood pressure (diastolic and systolic) was significant at the second week (paired t test, two-tailed probability, p less than or equal to 0.001). There were 62 dropouts: 10 due to inefficacy, 14 due to adverse reaction, and 38 due to other reasons. Laboratory examinations were performed before and after treatment and did not show statistical differences. Also, a 12-lead ECG was performed before and after treatment with K. The QTc was analyzed in a sample of 140 patients and did not show statistically significant changes. The incidence of side effects was minimal (24% of the patients, n = 224), mild, and transient; only 1% of the patients dropped out due to adverse reactions. In our experience, ketanserin was an effective and safe drug, to be used primarily for the treatment of mild to moderate H.

Adult↗
PubMed1986

Chagas' disease.

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Acute Disease↗
PubMed1986

Blind randomized cross-over comparative study of salbutamol and the combination fenoterol-ipratropium IK6 in patients with bronchial asthma.

A blind randomized cross-over comparative study of salbutamol and the combination fenoterol/ipratropium was carried out in 20 patients with mild to moderate bronchial asthma; clinical and functional serial parameters were evaluated. The combination was more effective than salbutamol in preventing crisis and incidence of cough and wheezing, and in the spirometric results. There were no significant differences in expectoration and the functional parameters improved not only in flow but also in volume. Pathogenesis is discussed.

Adolescent↗
PubMed1985

Thyroid cancer. Survival in 148 cases followed for 10 years or more.

One hundred forty-eight patients with differentiated carcinoma of the thyroid treated between May 1954 and April 1973 are presented. There were 89 papillary and 59 follicular carcinomas. They were classified according to Woolner criteria. Treatment consisted of surgery I-131 and thyroid hormone. Recurrences occurred in 8.7% of the patients, and lethality at the end of the observation period was 3.3%. The impact of histologic type, extent of the primary, and age of the patient at the time of treatment on prognosis were studied. The data were submitted to statistical analysis. This study revealed that these factors are determinant on prognosis. Best survival rates were observed in patients 40 years of age or younger at the time of treatment, in patients with intrathyroid papillary carcinomas, and in patients with noninvasive follicular carcinomas.

Adenocarcinoma↗