Search PubMed⌕ Search

Biomedical subjects

J Rivera

Publications and source records attributed to J Rivera.

At least 217 records · Page 12Linked to original sources
PubMed1989

Progesterone versus dehydrogesterone as replacement therapy in women with premature ovarian failure.

Dehydrogesterone (DH) induces normal endometrial secretory patterns in infertile as well as post-menopausal women, and has been successfully employed in the treatment of luteal-phase defects. The purpose of this study was to compare DH and progesterone (P) as progestins in steroid replacement cycles in eight women with premature ovarian failure (POF). Patients were treated during two subsequent cycles. Oestradiol valerate was used as the oestrogen. Four women received P as progestin in the first treatment cycle, while the remaining four patients began with DH. Histological dating and total protein content of uterine fluids (PCUF) were used as markers of P action on the endometrium. Samples were obtained on days 18-19 (early luteal phase, ELP) and day 26 of each cycle. Five regularly cycling women served as control for the normal range of PCUF. Histological dating of the endometrium showed ELP out-of-phase glands in 37.5% of cases treated with DH in comparison to none in the P group. Moreover, a characteristic ELP stromal haemorrhagic suffusion and increased oedema were present at the surface of the endometrium in all cases treated with DH. There was no histological difference between treatments on day 26 of the cycle. A significant (P less than 0.05) decrease in PCUF was observed in DH-treated endometria in comparison to P-treated endometria and controls. All three cases dated as out-of-phase endometria in the ELP had a PCUF less than or equal to 0.5 mg/ml. There was no difference between groups in PCUF on day 26. In conclusion, the morphological and biochemical data suggest that the endometrium supplemented with DH in women with POF fails to present optimal conditions for implantation of human embryos in the ELP. It is recommended that oral DH should not replace i.m. P as the progestin in steroid replacement cycles.

Adult↗
PubMed1989

[Evaluation of the reliability of anthropometric measures].

As part of the Early Malnutrition and Its Effects on Youth Project, a study of the reliability of anthropometric measures was carried out through the re-measurement of 226 adolescents of the rural area of Guatemala. In all anthropometric variables, the intra-measure coefficients of reliability were higher than 0.96 and the inter-measure coefficients of reliability higher than 0.91. A significant effect of the measure was found, suggesting the existence of systematic differences among measures. This information will permit corrections by measure effect in the analysis of data. The effect of different grades of "data editing" and "validity, reliability and agreement check", of measures was evaluated. The conclusion was that even though the persons in charge of measurements were trained and supervised, the deletion of values outside ranks did not result in an appreciable decrease of the technical error of measurement. As expected, data editing and validity carried out through the comparison of two measurements taken from each subject and eliminating those whose differences were classified as error according to statistical criteria, decreased the technical error of measurement, in most of the variables measured. Nevertheless, with the exception of one of the variables, this decrease was not marked. This indicates that the technical error of measurement obtained from all the subjects, many of whom were not re-measured, was within acceptable ranks. Results of the study demonstrate the importance of including re-measurement of a certain percentage of subjects when designing anthropometric studies. This will allow evaluation of the reliability of measurements, identification of bias due to measurements, and their correction.

Adolescent↗
PubMed1989

[Interaction of dietary intake and diarrheal disease in child growth].

There is evidence in the literature of the negative effects of diarrheal disease, and of the positive effects caused by food supplementation in postnatal growth. The present study analyzes the nature of the relationship between the effects of diarrheal disease and food supplementation on the growth of children of a rural area of Guatemala. The data analyzed were collected in a longitudinal study on food supplementation carried out by INCAP during the period comprised between 1969 and 1977. An important negative effect of diarrheal disease on growth was found on children three to 36 months of age with low dietary intake. Nevertheless, it was found that the negative effect of diarrheal disease on growth was lower in children whose dietary intake had important increments. In contrast, as compared with a study carried out in Colombia, where the supplementary feeding effect was restricted to groups with higher incidence of diarrhea, the supplementation effect on growth of Guatemalan children was found to be present at all levels of prevalence of diarrheal diseases. This article discusses the possible causes of the different results found in the Colombian study, as compared with those derived from the present study.

Child, Preschool↗
PubMed1989

[School feeding program in Guatemala: technology transfer to artisan bakers, producers of the nutritionally improved cookie].

The Ministry of Education of Guatemala requested from the Institute of Nutrition of Central America and Panama (INCAP), the development of a solid food for delivery to school children who attend the official schools throughout the country. INCAP developed and transferred the processing technology to produce a nutritionally improved cookie to artisan bakers from the different regions of the country. The present paper describes the technological process, focusing on the training, supervision and quality control actions executed with approximately 100 micro baking enterprises, in 1988 and 1989. These actions have had a positive impact on the bakeries, a fact evidenced by the significant improvement of the conditions and processes of the nutritionally improved cookie production. The performance of the above-mentioned activities has allowed us to detect necessities, for the solution of which research and development of technologies are most important for their immediate transference to artisan bakers. Nevertheless, it is necessary to monitor and control the transferred technology, and efforts must continue to increase the effectiveness of the whole system which involves technology transference model, created for this project.

Child↗
PubMed1989

Emerging picture of the receptor with high affinity for IgE.

The cDNAs for two of the subunits of the receptor with high affinity for IgE have been isolated and sequenced. That for the IgE-binding alpha subunit predicts a polypeptide with a single transmembrane segment. The predicted extracellular amino terminal portion, comprised of 180 residues, is homologous to the corresponding region of Fc gamma receptors and contains two truncated immunoglobulin-like domains. The cDNA for beta predicts a peptide with four transmembrane segments, but its sequence is unrelated to known proteins. Experiments to isolate the cDNA for the gamma subunit have begun; when completed, cotransfection of the three genes will be attempted to get expression, a process that has not so far been successful for the individual subunits. Such expression will permit further analysis of the receptor's function and ultimately may provide information on how best to intervene clinically in the activation of mast cells and basophils.

Animals↗
PubMed1989

Synchronous hepatocellular carcinoma and adenocarcinoma of the colon.

It is not uncommon for patients with colon cancer to have a second primary neoplasm. The reported incidence of synchronous colon tumors is approximately about 3 to 4 per cent. Colon cancer also may be associated with a synchronous extra-colonic neoplasm; this incidence is less well defined and certainly is less emphasized in the literature. The authors recently treated a patient who had a synchronous hepatoma and adenocarcinoma of the colon. This appears to be the first report of these tumors presenting synchronously. The patient had both tumors resected and has no evidence of recurrence ten months later. This case illustrates the need to seek both colonic and extra-colonic synchronous tumors in patients discovered to have a colon cancer.

Adenocarcinoma↗
PubMed1988

Application of fast atom bombardment and tandem mass spectrometry to the identification of organic micropollutants in water.

Organic compounds in raw and drinking water, not amenable to gas chromatography/mass spectrometry, were characterized by fast atom bombardment (FAB) and collision-induced decomposition/mass-analysed ion kinetic energy (CID/MIKE) spectrometry. Anionic, cationic and non-ionic surfactants were successfully identified by comparison of their FAB spectrum and CID/MIKE of prominent ions with commercial standards. Organic dyes were spiked to water extracts and the detection limit for some of them reported.

Chromatography, High Pressure Liquid↗
PubMed1988

Studies with a monoclonal antibody to the beta subunit of the receptor with high affinity for immunoglobulin E.

The receptor with high affinity for IgE consists of a tetrameric complex of polypeptides, one of which (alpha), contains the binding site for IgE. The function of the other chains--a single beta and two disulfide-linked gamma chains--is unknown. We report the cloning of a murine hybridoma that secretes an IgG1 antibody which specifically reacts with the beta subunit. Studies with this monoclonal antibody show that the subunit stoichiometry of the receptor is unaffected by the presence or absence of bound IgE. We also found that under certain conditions where the alpha beta gamma 2 complex dissociates, beta remains attached to the dimer of gamma chains, indicating that these chains contact each other in the native receptor. In rat basophilic leukemia cells--a neoplastic line of mucosal-type mast cells--all of the beta subunits expressed by the cells appeared to be associated with the high affinity receptor. However, in at least one cell line which has no high affinity receptors--a putative rat lymphoma line--beta or beta-like polypeptides were also expressed.

Animals↗
PubMed1988

Immunoradiometric studies with a monoclonal antibody against an estrogen-receptor-related protein in human breast cancer.

The concentration of P29, a phosphoprotein related to estradiol receptor (RE), was measured by an immunoradiometric assay in human breast cancer cytosol and the results compared with the levels of RE and progesterone receptors (RP), as measured by the classical ligand-binding assay. Good linear correlation was found between P29 and RE, but not RP. Tumors which were positive for both RE and RP had a higher P29 mean value than RE-negative, RP-negative tumors. Menopausal status of the patients influenced the result, since premenopausal women had lower mean concentrations or were P29-positive less frequently than postmenopausal women. RE-negative, RP-positive tumors tended to have positive P29 levels. The correlation between RE and P29 corroborates results obtained with other techniques and supports a role for P29 in predicting response to hormonal treatment.

Antibodies, Monoclonal↗
PubMed1988

Nutritional supplementation during two consecutive pregnancies and the interim lactation period: effect on birth weight.

The study consisted of 169 mothers enrolled during two consecutive pregnancies and the intervening lactation period in the Guatemalan Nutritional Supplementation Study. Women were grouped for this analysis according to the levels of caloric supplementation that they received (high or low) during two consecutive pregnancies and the period between them. The supplement also contained minerals and vitamins. Data were analyzed adjusting for maternal height, birth interval, parity, length of lactation, socioeconomic status, birth weight of the first offspring, gestational age of the second offspring, and caloric supplementation, expressed either in continuous fashion (total intake) or as caloric supplementation per week. The adjusted mean birth weights of the second offspring of women with high supplementation during two pregnancies (about an extra 180 kcal/d), and the in-between lactation period (about an extra 245 kcal/d), were up to 301 g greater than that of the low supplementation group. Women with high supplementation while breast-feeding their first offsprings and during their second pregnancies had babies up to 150 g heavier than the reference group; those mothers with high supplementation only during the second pregnancy had infants about 124 g heavier than those of the low supplementation group. Therefore, high supplementation during two consecutive pregnancies and their intervening lactation period among chronically, yet moderately, malnourished women was capable of increasing the mean birth weight to levels closer to those reported for industrialized populations. The mean birth weight increase is between two and three times greater than the effect shown in almost all of the previous studies of this topic.

Birth Weight↗
PubMed1987

Lectin binding and inhibition studies reveal the importance of D-glucose, D-mannose and N-acetylglucosamine during early sexual development of Dictyostelium discoideum.

Fluorescein-conjugated and non-conjugated lectins were used to determine which surface sugars are involved in the early events of sexual (macrocyst) development in Dictyostelium discoideum. Only zygote giant cells showed unique binding of FITC-WGA and FITC-PNA while all cell types (amoebae, gametes, binucleates, giant cells) showed identical patterns of FITC-Con A, -Gorse and -RCA II binding. In spite of its non-selective labelling of all cell types, Con A inhibited macrocyst formation. The temporal addition of Con A with and without specific hapten sugars indicates the importance of both D-mannose and D-glucose in phagocytosis and, possibly, cell fusion. WGA also inhibited macrocyst formation. Varying the time of addition of the lectin plus/minus its primary hapten sugar implicates N-acetylglucosamine as being important in cell fusion. Neither Gorse, RCA II nor PNA had any detectable inhibitory effects on macrocyst development leaving the appearance of increased PNA receptors at the giant cell surface as an enigma.

Acetylglucosamine↗
PubMed1987

Analgesic efficacy of two ibuprofen-codeine combinations for the treatment of postepisiotomy and postoperative pain.

Our purpose was to compare the analgesic efficacy and safety of single oral doses of the combination of ibuprofen 400 mg plus codeine 60 mg and the combination of ibuprofen 200 mg plus codeine 30 mg with ibuprofen 400 mg alone, codeine sulfate 60 mg alone, and placebo. One hundred ninety-five patients with severe pain resulting from episiotomy, cesarean section, or gynecologic surgery completed a randomized, double-blind, stratified, parallel-group study. Patients were observed during a 4-hour period after medication. Based on the sum of the pain intensity differences (SPID), total pain relief (TOTPAR), and most of the hourly direct measures of pain and relief, both doses of the combination and ibuprofen 400 mg alone were statistically superior to placebo. Codeine 60 mg was statistically superior to placebo based on TOTPAR, the global ratings, and a few hourly measures. The mean effect of the combination of ibuprofen 400 mg plus codeine 60 mg was significantly superior to the mean effect of ibuprofen 400 mg alone 1/2, 1, and 2 hours after medication and to the mean effect of ibuprofen 400 mg alone and codeine 60 mg alone for SPID, TOTPAR, and other measures as well. The low-dose combination was significantly more effective than codeine 60 mg for a few hourly measures but was not significantly superior to ibuprofen 400 mg. Based on these findings it appears that the combination of ibuprofen 400 mg plus codeine 60 mg, particularly in the first few hours after medication, is more efficacious than its constituents.

Adult↗
PubMed1987

GC/MS, HPLC and FAB mass spectrometric analysis of organic micropollutants in Barcelona's water supply.

Water samples from Llobregat river entering two water work plants, Barcelona tap water and waste dumping samples taken along the river course were analyzed for trace organic contaminants by different procedures, liquid-liquid extraction, adsorption on granular activated carbon followed by GC/MS/DS. Ether insoluble organic fractions were analyzed and fractionated by HPLC with diode-array detection, followed by FAB and FAB-CID-MIKE characterisation. Results, after two years monitoring, proved that surfactants, plasticizers, ethyleneglycol derivatives, phosphates, hydrocarbons and other miscellaneous compounds can be considered as chronic pollutants of Llobregat river. Some of the identified compounds by GC/MS and FAB mass spectrometry have not been previously reported to occur in water.

Chromatography, High Pressure Liquid↗