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1.
J Environ Manage ; 223: 358-370, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29936349

RESUMEN

Characterisation of 27 types of biomass was performed together with an assessment of regional resource availability. Charcoal was produced under two conditions from all samples and their yields were compared. Sugarcane bagasse, sal and pine produced the best charcoal with a low volatile matter and high calorific value. The amount of high-quality charcoal which can be made within Nepal from the biomass types tested is equivalent to 8,073,000 tonnes of firewood a year or 51% of the yearly demand. The areas which would benefit the most from charcoal making facilities are the Mid-hills of the Western, Central and Eastern Development Regions, as well as the Terai in the Central and Eastern Development Regions. The main potential benefit is to convert agricultural residues which are underutilised because, in their original form, produce large quantities of smoke, to cleaner burning charcoal. The conversion of agricultural residues to charcoal is also a viable alternative to anaerobic digestion in the Mid-hills.


Asunto(s)
Agricultura , Carbón Orgánico , Saccharum , Biomasa , Celulosa , Nepal
2.
J Nepal Health Res Counc ; 13(31): 188-95, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27005710

RESUMEN

BACKGROUND: Family planning (FP) is one of the major components of reproductive health and its goal is to prevent unwanted pregnancies and regulate wanted pregnancies, thereby ensuring the health of mothers and children. It also aims at regulating the population in order to maintain the vital balance between development and the environment. Ideally, FP depends on the efforts of a couple where the man and woman are equally responsible and accountable. In reality, however, this is not the case. It is in this background that the present study aims at examining the nature and level of male participation in preventing unwanted pregnancies and the factors that influence male participation in FP. METHODS: The data for the study was derived using mixed methods, drawing from both quantitative and qualitative approaches. The research design was cross-sectional, descriptive and observational. RESULTS: Despite the high level of knowledge and awareness about FP among the respondents, it was found that male participation in FP continues to remain very low. The multidimensional factors influencing their participation include education of the couple (the unadjusted odds ratio of higher education level of respondents is 2.182 and the adjusted OR is 1.972; and the unadjusted OR of higher education level of the spouse is 2.030, and the adjusted OR is 1.570), and economic condition (the unadjusted OR of higher income is 2.272 and the adjusted OR is 2.436) of family. Male participation in FP was found to be higher in rural areas (69.8 %) and among Dalits (72.5%). Other factors include social stigma and religious practice, patriarchal notions, gender roles and individual characteristics. CONCLUSIONS: Male participation plays a crucial role in population management, but patriarchal notions, socioculturally defined gender roles, combined with the inefficiency of the current FP programme, and biological factors contribute towards keeping male participation very low.


Asunto(s)
Servicios de Planificación Familiar , Conocimientos, Actitudes y Práctica en Salud , Hombres , Adulto , Estudios Transversales , Toma de Decisiones , Femenino , Humanos , India , Masculino , Masculinidad , Encuestas y Cuestionarios
3.
Endocrinology ; 133(4): 1490-503, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8404588

RESUMEN

The biological significance of glycosylation variants of pituitary glycoprotein hormones remains controversial because of the indirect methods usually employed to determine carbohydrate composition or structure as well as the use of unreliable biological/immunological ratio to determine bioactivity. We have previously characterized recombinant human TSH (rhTSH) secreted by Chinese hamster ovary cells attached to microcarrier beads in a large scale bioreactor after stable transfection of hCG alpha and hTSH beta minigenes. In the present study rhTSH has been used as a model to determine structure-function relationships of different isoforms of glycoprotein hormones. We have now produced greater than 200 mg rhTSH using a hollow fiber bioreactor. The highly purified rhTSH produced in the hollow fiber bioreactor (rhTSH-N) as well as rhTSH commercially produced in a large scale bioreactor (rhTSH-G) were quantitated by immunoassays, receptor binding assay, and amino acid analysis and further characterized by a variety of physico-biochemical methods, including chromatofocusing and carbohydrate analysis. rhTSH-G, rhTSH-N, as well as pituitary human TSH (phTSH) have been separated by chromatofocusing on a Mono P column into several isoforms with different pI values. Compositional analysis of the fractions showed higher sialic acid content in the more acidic rhTSH-G fractions. phTSH acidic isoforms showed higher total sulfate and sialic acid contents than the more basic fractions. The bioactivities of various TSH isoforms based on rigorous quantitation of mass by amino acid analysis determined in three different FRTL-5 cell bioassays showed that the more basic and less sialylated fractions of rhTSH-G were more active than the more acidic fractions. In contrast to the in vitro data, highly sialylated and acidic rhTSH-G isoforms showed longer plasma half-lives and higher in vivo bioactivity than the basic forms. These results indicate that secreted rhTSH, similar to intrapituitary phTSH, exists as a mixture of charge isoforms that are related at least in part to the degree of sialylation. The degree of sialylation, highly dependent on the bioreactor production conditions, appears to be the major factor affecting the charge heterogeneity, MCR, and bioactivity of rhTSH.


Asunto(s)
Ácidos Siálicos/metabolismo , Sulfatos/metabolismo , Tirotropina/química , Tirotropina/aislamiento & purificación , Aminoácidos/análisis , Animales , Bioensayo , Células CHO , Carbohidratos/análisis , Línea Celular , Cricetinae , AMP Cíclico/biosíntesis , Electroforesis en Gel de Poliacrilamida , Isomerismo , Ácido N-Acetilneuramínico , Ensayo de Unión Radioligante , Proteínas Recombinantes , Tirotropina/metabolismo
4.
Arch Biochem Biophys ; 261(1): 134-47, 1988 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-3124764

RESUMEN

Sodium and other monovalent cations (added as chloride salts) inhibited adenylate cyclase of luteinized rat ovary. Sodium chloride (150 mM) inhibited basal enzyme activity by 20%. Sodium chloride inhibition was enhanced to 34-54% under conditions of enzyme stimulation by guanine nucleotides (GTP and its nonhydrolyzable analog 5'-guanylyl imidodiphosphate), fluoride anion, and agonists (ovine luteinizing hormone (oLH) and the beta-adrenergic catecholamine isoproterenol) acting at stimulatory receptors linked to adenylate cyclase. Sodium chloride inhibition was dependent on salt concentration over a wide range (25-800 mM) as well as the concentrations of GTP and oLH. Inhibition by NaCl was of rapid onset and appeared to be reversible. The order of inhibitory potency of monovalent cations was Li+ greater than Na+ greater than K+. The role of individual components of adenylate cyclase in the inhibitory action of monovalent cations was examined. Exotoxins of Vibrio cholerae and Bordetella pertussis were used to determine respectively the involvement of the stimulatory and inhibitory guanine nucleotide-binding regulatory components (Ns and Ni) in NaCl inhibition. Sodium chloride inhibited cholera toxin-activated adenylate cyclase activity by 29%. Ni did not appear to mediate cation inhibition of adenylate cyclase because pertussis toxin did not attenuate inhibition by NaCl. Enzyme stimulation by agents (forskolin and Mn2+) thought to activate the catalytic component directly was not inhibited by NaCl but was instead significantly enhanced. Sodium chloride (150 mM) increased both the Kd for high-affinity binding of oLH to 125I-human chorionic gonadotropin binding sites and the Kact for oLH stimulation of adenylate cyclase by sevenfold. In contrast, NaCl had no appreciable effect on either isoproterenol binding to (-)-[125I]iodopindolol binding sites or the Kact for isoproterenol stimulation of adenylate cyclase. The results suggest that in luteinized rat ovary monovalent cations uncouple, or dissociate, Ns from the catalytic component and, in a distinct action, reduce gonadotropin receptor affinity for hormone. Dissociation of the inhibitory influence of Ni from direct catalytic activation could account for NaCl enhancement of forskolin- and Mn2+-associated activities. On the basis of these results, the spectrum of divergent stimulatory and inhibitory effects of monovalent cations on adenylate cyclase activities in a variety of tissues may be interpreted in terms of differential enzyme susceptibilities to cation-induced uncoupling of N and catalytic component functions.


Asunto(s)
Inhibidores de Adenilato Ciclasa , Proteínas de Unión al GTP/metabolismo , Ovario/enzimología , Receptores de HL/metabolismo , Animales , Cationes Monovalentes , Gonadotropina Coriónica/farmacología , Femenino , Gonadotropinas Equinas/farmacología , Cinética , Ovario/efectos de los fármacos , Ovario/fisiología , Ratas , Ratas Endogámicas , Cloruro de Sodio/farmacología
5.
Second Messengers Phosphoproteins ; 12(2-3): 105-21, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3149674

RESUMEN

We have examined the effects of sodium (Na+) salts on rat liver adenylate cyclase. Increasing concentrations of Na+ salts produced biphasic stimulation and inhibition of adenylate cyclase and potentiated enzyme activation by GTP and its hydrolysis resistant analog 5'-guanylyl imidodiphosphate. Salt effects were temperature dependent, of rapid onset, and specific for the Na+ cation though also partly dependent on the accompanying anion. Sodium salt stimulation of adenylate cyclase and enhancement of GTP activation were attenuated by agents (pertussis toxin and N-ethylmaleimide) which inactivate the inhibitory guanine nucleotide-binding regulatory component (Gi) of adenylate cyclase. Cholera toxin, which activates the stimulatory guanine nucleotide-binding regulatory component (Gs) of adenylate cyclase and thereby increases enzyme activity, augmented the inhibitory phase of Na+ salt action. These results suggest that the stimulatory and inhibitory effects of Na+ salts may be due, respectively, to inhibition of Gi and Gs modulation of adenylate cyclase.


Asunto(s)
Inhibidores de Adenilato Ciclasa , Azidas/farmacología , Proteínas de Unión al GTP/fisiología , Hígado/enzimología , Cloruro de Sodio/farmacología , Toxina de Adenilato Ciclasa , Adenilil Ciclasas/metabolismo , Animales , Cationes Monovalentes/farmacología , Toxina del Cólera/farmacología , Relación Dosis-Respuesta a Droga , Etilmaleimida/farmacología , Masculino , Manganeso/farmacología , Toxina del Pertussis , Ratas , Ratas Endogámicas , Azida Sódica , Factores de Tiempo , Factores de Virulencia de Bordetella/farmacología
6.
Endocrinology ; 113(6): 2145-54, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6641628

RESUMEN

We have examined the interaction of certain forms of mouse (m) tumor and bovine (b) pituitary TSH with standard bTSH on the activation of adenylate cyclase in human thyroid membranes. Tumor extract, serum from tumor-bearing mice, culture medium from dispersed cell incubations, and two preparations of purified bTSH (Sigma and Pierce) were fractionated on Sephadex G-100 (1.2 X 200 cm). For each fraction, TSH bioactivity was measured by stimulation of adenylate cyclase activity in human thyroid membranes, and immunoactivity was determined by RIA. On G-100, Pierce bTSH had multiple immunoactive components with partition coefficients (Kav) of 0.28-0.32 and ratios of biological over immunological activity (B/I) of 0.59-1.42. Sigma bTSH, mouse tumor, serum, and medium were even more heterogeneous (Kav = 0.23-0.32), with a lower range of B/I (0.04-1.0). When single doses (125-2000 ng) of those fractions with the highest Kav (0.30-0.32) and lowest B/I (0.04-0.51) were mixed with multiple doses (200-10,000 microU) of Armour TSH standard (B/I = 1), there was 30-56% inhibition of adenylate cyclase activity stimulation. Double reciprocal plots showed competitive inhibition for the low B/I forms from all sources, except for a medium form which showed mixed inhibition. The medium form had the highest inhibitory activity. There were no inhibitors in G-100 fractions from the Kav regions devoid of TSH immunoactivity or from the same Kav regions of normal mouse serum. To determine the chemical differences between different forms, affinity chromatography on Concanavalin A, wheat germ agglutinin, and soybean agglutinin was employed. Compared with the apparent higher molecular weight form with higher B/I, the apparent lower molecular weight form with lower B/I contained decreased amounts or availability of alpha-mannose and increased amounts or availability of beta-N-acetyl-D-galactosamine and/or beta-galactose; both forms appear to contain similar beta-N-acetyl-D-glucosamine residues, presumably in the inner core.


Asunto(s)
Adenilil Ciclasas/metabolismo , Carbohidratos/análisis , Glándula Tiroides/enzimología , Tirotropina/farmacología , Animales , Unión Competitiva , Bovinos , Cromatografía de Afinidad , Activación Enzimática/efectos de los fármacos , Humanos , Lectinas , Ratones , Neoplasias Hipofisarias/análisis , Tirotropina/análisis , Tirotropina/inmunología
7.
Arch Androl ; 5(2): 179-88, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6775607

RESUMEN

Low-molecular-weight (< 1500 daltons) peptides with inhibin activity have been isolated from sheep testes and ovaries by simple gel filtration. These peptides were capable of inhibiting the ovarian weight increase in hCG-primed immature female mice and also of suppressing the post-castration rise of serum FSH levels in adult male rats, suggesting similarities in their biological properties. Both testicular and ovarian inhibin were typsin sensitive and heat stable at 100 degrees C for 30 min and were shown to act by interfering with the production of a hypothetical FSH-RH.


Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Ovario/análisis , Proteínas/aislamiento & purificación , Hormonas Testiculares/aislamiento & purificación , Testículo/análisis , Animales , Femenino , Hormona Folículo Estimulante/metabolismo , Hormona Liberadora de Gonadotropina/aislamiento & purificación , Hormona Liberadora de Gonadotropina/metabolismo , Hormona Liberadora de Gonadotropina/farmacología , Hormonas/farmacología , Inhibinas , Riñón/análisis , Hígado/análisis , Hormona Luteinizante/metabolismo , Masculino , Proteínas/farmacología , Ovinos , Hormonas Testiculares/farmacología
9.
J Reprod Fertil Suppl ; (26): 71-85, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-293412

RESUMEN

This communication presents evidence for the existence in the ovine testis of proteinaceous factors which suppress LH as well as FSH. Isolation of these factors has been achieved by using three different procedures: cytosol preparation, metaphosphoric acid extraction and ultrafiltration. Chromatography of cytosol or metaphosphoric acid extract on Sephadex G-75 resulted in separation into three protein fractions designated as G-75-I, II and III in order of their elution. When administered to castrated male rats, Fraction G-75-I suppressed circulatory levels of LH (53% inhibition, P less than 0.05) without altering FSH. The most retarded fraction, G-75-III, suppressed FSH (29% inhibition, P less than 0.001) without any concomitant change in LH. When fraction G-75-III was further fractionated on Sephadex G-25, three components were found and two, G-25-II and G-25-III, were biologically active. These fractions were homogeneous on polyacrylamide disc-gel electrophoresis. The FSH-suppressing factor (inhibin) was heat labile and susceptible to trypsin digestion, indicating that it is proteinaceous. Treatment with urea did not reveal any subunits. The molecular weight of this factor, as determined by gel filtration and SDS-urea gel electrophoresis was estimated to be around 1400-1500. The absence of sialic acid and the molecular weight data suggested that the isolated material was a simple protein and probably a small peptide. Gel filtration on Sephadex G-75 of the metaphosphoric acid extracts of liver, kidney, testis and ovary revealed an identical elution pattern for ovarian and testicular inhibin.


Asunto(s)
Hormona Folículo Estimulante/metabolismo , Ovario/análisis , Proteínas/aislamiento & purificación , Hormonas Testiculares/aislamiento & purificación , Testículo/análisis , Animales , Bioensayo/métodos , Cromatografía en Gel , Citosol/análisis , Depresión Química , Electroforesis en Gel de Poliacrilamida , Femenino , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Masculino , Ratones , Peso Molecular , Proteínas/análisis , Proteínas/farmacología , Ratas , Ovinos , Hormonas Testiculares/análisis , Hormonas Testiculares/farmacología
11.
Indian J Med Res ; 64(11): 1649-56, 1976 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-798724

RESUMEN

PIP: A specific and highly sensitive radioimmunoassay technique for the measurement of gonadotropin releasing hromone (GRH) in unextracted human serum is reported. 37 serum samples were analyzed for GRH, luteinizing hormone (LH) and follicle stimulating hormone (FSH). Plasma levels of GRH and LH, but not FSH, showed similar patterns during the menstrual cycle. GRH was also detectable throughout the course of pregnancy.^ieng


Asunto(s)
Hormonas Liberadoras de Hormona Hipofisaria/sangre , Radioinmunoensayo/métodos , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Menstruación , Embarazo
14.
Am J Obstet Gynecol ; 121(3): 300-5, 1975 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-46715

RESUMEN

Sixty-one sera from different trimesters of pregnancy were analyzed by two 125-I-NIH-HCG assay systems, employing anti-intact HCG serum and anti theta-HCG serum, respectively. The ratios of the levels measured in the two assay systems changed with the duration of pregnancy. The ratios during trimesters 1,2, and 3 were 2.94, 1.99, and 2.37, respectively. The cross-reactivity of proteohormones other than HCG was tested in both the assay systems. The two assay systems could be comparable in their high degree of specificity. However, the relative affinities of intact HCG and theta-HCG in the two assay systems were observed to be different. It was suggested that the significant differences in the ratios of the levels measured by the tow assay systems might have been infulenced by the occurrence of theta-HCG in serum and that the levels of the subunit must have changed at different stages of pregnancy.


Asunto(s)
Gonadotropina Coriónica/sangre , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Animales , Reacciones Cruzadas , Femenino , Hormona Folículo Estimulante/inmunología , Glicoproteínas/sangre , Humanos , Hormona Luteinizante/inmunología , Fragmentos de Péptidos , Embarazo , Radioinmunoensayo , Ovinos/inmunología , Tirotropina/inmunología , gammaglobulinas
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