RESUMEN
The objective of this study was to determine the effects of dietary n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on the organ indexes, and histological and ultrastructures of organs including liver, spleen and thymus in 70-day-old Yangzhou goslings. One-hundred and sixty 21-day-old Yangzhou goslings were randomly divided into 4 groups and fed 4 diets varying in the n-6/n-3 PUFA ratio from 3:1 up to 12:1. After 1-week acclimation, the feeding experiment lasted for 6 weeks. At the end of the experimental period, goslings were slaughtered and the liver, spleen and thymus were weighed, and their histological and ultrastructures were examined. The results showed that the organ indices in the 3:1 group were remarkably higher than in the other three groups, whereas the mitochondrial square did not differ among four groups. The histological and ultrastructures of the liver, spleen and thymus were not affected by the diets with the lower n-6/n-3 PUFA ratios (3:1 and 6:1). However, feeding diets with the higher n-6/n-3 PUFA ratios (9:1 and 12:1), the nuclear chromatin was concentrated and marginalized; the cell membrane was contracted inwardly and disrupted; the mitochondrial membrane was damaged to some degree. In conclusion, the diet containing higher content of n-3 PUFA might improve immune capacity of goslings the animal by accelerating the growth and maintaining cellular structures of organs like liver, spleen and thymus.
Asunto(s)
Anseriformes , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-6/farmacología , Hígado/efectos de los fármacos , Bazo/efectos de los fármacos , Timo/efectos de los fármacos , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Femenino , Hígado/ultraestructura , Masculino , Bazo/ultraestructura , Timo/ultraestructura , Aumento de Peso/efectos de los fármacosRESUMEN
ß-Hydroxybutyric acid (BHBA) has recently been shown to regulate hormone synthesis and secretion in the hypothalamus. However, little is known about the effects of BHBA-mediated hormone regulation or the detailed mechanisms by which BHBA regulates growth hormone-releasing hormone (GHRH) synthesis and secretion. In the present study, we examined the expression of the BHBA receptor GPR109A in primary hypothalamic cell cultures. We hypothesised that BHBA regulates GHRH via GPR109A and its downstream signals. Initial in vivo studies conducted in rats demonstrated that GHRH mRNA expression in the hypothalamus was strongly inversely correlated with BHBA levels in the cerebrospinal fluid during postnatal development (r = -0.89, P < 0.01). Furthermore, i.c.v. administration of BHBA acutely decreased GHRH mRNA expression in rats. Further in vitro studies revealed a decrease in GHRH synthesis and secretion in primary hypothalamic cells after treatment with BHBA; this effect was inhibited when hypothalamic cells were pretreated with pertussis toxin (PTX). BHBA had no effect on GHRH synthesis and secretion in GT1-7 cells, which do not exhibit cell surface expression of GPR109A. Furthermore, BHBA acutely decreased the transcription of the homeobox gene for Gsh-1 in the hypothalamus in both in vivo and in vitro, and this effect was also inhibited by PTX in vitro. In primary hypothalamic cells, BHBA activated the extracellular signal-regulated kinase (ERK)1/2, p38 and c-Jun N-terminal kinase mitogen-activated protein kinase (MAPK) kinases, as shown by western blot analysis. Moreover, inhibition of ERK1/2 with U0126 attenuated the BHBA-mediated reduction in Gsh-1 expression and GHRH synthesis and secretion. These results strongly suggest that BHBA directly regulates GHRH synthesis and secretion via the GPR109A/ERK1/2 MAPK pathway, and also that Gsh-1 is essential for this function.
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Ácido 3-Hidroxibutírico/fisiología , Hormona Liberadora de Hormona del Crecimiento/biosíntesis , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hipotálamo/metabolismo , Receptores Acoplados a Proteínas G/biosíntesis , Receptores Nicotínicos/biosíntesis , Transducción de Señal , Ácido 3-Hidroxibutírico/antagonistas & inhibidores , Ácido 3-Hidroxibutírico/líquido cefalorraquídeo , Ácido 3-Hidroxibutírico/farmacología , Animales , Butadienos/farmacología , Células Cultivadas , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Proteínas de Homeodominio/biosíntesis , Humanos , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Nitrilos/farmacología , Toxina del Pertussis/farmacología , Cultivo Primario de Células , Ratas , Transducción de Señal/efectos de los fármacosRESUMEN
Heat stress adversely affects the productivity and immune status of dairy cows. The temperature-humidity index (THI) is commonly used to indicate the degree of heat stress on dairy cattle. We investigated the effects of different THI and Cr supplementation on the antioxidant capacity, the levels of heat shock protein 72 (Hsp72), and cytokine responses of lactating cows. The study used a total of 24 clinically healthy uniparous midlactation Holstein cows, which were randomly divided into 2 groups (n = 12 per group), and was conducted in 3 designated THI periods: low THI period (LTHI; THI = 56.4 ± 2.5), moderate THI period (MTHI; THI = 73.9 ± 1.7), and high THI period (HTHI; THI = 80.3 ± 1.0). The 2 groups of cows were fed corn and corn silage based basal diet supplemented chromium picolinate to provide 3.5 mg of Cr/cow daily (Cr+) or basal diet with no Cr (Cr-). The experiment was a 3 × 2 factorial design. The numbers of leukocytes (P < 0.05) and serum levels of glucose (P < 0.001) were lower; however, the serum levels of blood urea nitrogen (BUN; P < 0.001) and creatinine (P < 0.001) were greater in the MTHI and HTHI than in LTHI. The total antioxidant capacity in the serum was unaltered; an increase in superoxide dismutase activity (P < 0.001) and in serum malondialdehyde concentration (P < 0.001) was observed in the MTHI and HTHI compared with the LTHI. The high THI led to increases in serum concentrations of tumor necrosis factor-α (TNF-α; P < 0.001) and IL-10 (P < 0.05). Cows supplemented with Cr had lower (P = 0.009) serum concentrations of cholesterol but greater (P < 0.001, respectively) serum levels of Hsp72 and IL-10 compared with those without Cr supplementation in the HTHI. Western blot analysis revealed that cows supplemented with Cr had greater (P = 0.038) expression of the inhibitor of nuclear factor kappa B α (IκBα) in peripheral blood mononuclear cells (PBMC) compared with those without Cr supplementation in the HTHI, whereas the expression of Hsp72 in PBMC was unaltered. Data indicate that there is a decrease in glucose and increases in BUN and creatinine in the serum of midlactation cows under hot conditions during the summer and that these cows have a lowered oxidative capacity but an elevated antioxidant capacity. In addition, Cr may play an anti-inflammatory role in lactating cows by promoting the release of Hsp72, increasing the production of IL-10, and inhibiting the degradation of IκBα under hot conditions during the summer.
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Bovinos/fisiología , Citocinas/sangre , Proteínas del Choque Térmico HSP72/sangre , Respuesta al Choque Térmico/fisiología , Humedad/efectos adversos , Lactancia/fisiología , Oxidación-Reducción/efectos de los fármacos , Ácidos Picolínicos/farmacología , Animales , Bovinos/inmunología , Citocinas/fisiología , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Proteínas del Choque Térmico HSP72/fisiología , Respuesta al Choque Térmico/efectos de los fármacos , Calor/efectos adversos , Interleucina-10/sangre , Lactancia/efectos de los fármacos , Malondialdehído/sangre , FN-kappa B/sangre , Superóxido Dismutasa/sangre , Factor de Necrosis Tumoral alfa/sangreRESUMEN
The aim of this study was to investigate the anorectic mechanism of calcitonin gene-related peptide (CGRP) in rats. Intraperitoneal injection of CGRP (50 µg/kg) resulted in decline (p < 0.05) in the food intake of rats at 0.5, 1, 2 and 4 h in comparison with saline control. Compared with saline-treated group, the levels of hypothalamic 3',5'-cyclic adenosine monophosphate (cAMP) and plasma glucagon were increased (p < 0.05) in CGRP-treated group, but insulin level was decreased (p < 0.05). No significant changes (p > 0.05) in the plasma leptin were observed between two treatment groups. Calcitonin gene-related peptide injection down regulated (p < 0.05) both neuropeptide Y (NPY) and melanin-concentrating hormone (MCH) genes at mRNA levels, but up regulated (p < 0.05) the expression of cholecystokinin (CCK) gene. The correlations analysis showed that food intake was negatively correlated (p < 0.05) with CCK mRNA, cAMP and glucagon levels. Moreover, there existed negative correlations (p < 0.05) between MCH mRNA and glucagon levels, and positive correlations (p < 0.05) between insulin and leptin levels. The results showed that cAMP acting as the second messenger may play a vital role in the anorectic effects of CGRP. Calcitonin gene-related peptide could stimulate anorexigenic neuropeptides (i.e. CCK) and/or inhibit orexigenic neuropeptides (i.e. NPY and MCH) expression, and ultimately suppressed food intake that was functionally coupled to cAMP/PKA pathway activation.
Asunto(s)
Péptido Relacionado con Gen de Calcitonina/farmacología , Ingestión de Alimentos/efectos de los fármacos , Animales , Privación de Alimentos , Hipotálamo , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
The present study investigated the effect of different zinc (Zn) levels on activities of gastrointestinal digestive enzymes of growing rats. Four diets including Zn-adequate (ZA; 46 mg/kg, control), Zn-deficient (ZD; 3 mg/kg), high Zn supply (ZH; 234 mg/kg) and pair-fed in which animals received the ZA diet at restricted amounts reflecting feed intake of the ZD group were fed to rats for 5 weeks. Dietary Zn was supplemented with ZnO. The results showed that Zn deficiency resulted in decreases in body weight, while ZH supply stimulated growth. The activities of sucrase, lactase and lipase were unaffected by dietary Zn levels. Maltase activity, however, was reduced in ZD group and elevated in ZH group. Amylase and protease activities were depressed by zinc deficiency. However, rats fed the Zn-repletion diet displayed higher activity of pepsin, pancreatic amylase and protease. In particular, ZH supply did have no effect on intestinal hydrolases activities. The present study suggested that zinc deficiency impaired the activities of digestive enzymes and growth of animals. However, ZH supply might improve the digestion of nutrients via increasing activities of gastrointestinal hydrolase and probably enhanced animal health.
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Tracto Gastrointestinal/enzimología , Hidrolasas/metabolismo , Zinc/sangre , Zinc/farmacología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta , Suplementos Dietéticos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Mucosa Intestinal/enzimología , Yeyuno/enzimología , Masculino , Ratas , Ratas Sprague-Dawley , Zinc/administración & dosificaciónRESUMEN
Traditional Chinese medicine (TCM) has been widely practiced and is considered as an attractive to conventional medicine. Multi-herb recipes have been routinely used in TCM. These have been formulated by using TCM-defined herbal properties (TCM-HPs), the scientific basis of which is unclear. The usefulness of TCM-HPs was evaluated by analyzing the distribution pattern of TCM-HPs of the constituent herbs in 1161 classical TCM prescriptions, which shows patterns of multi-herb correlation. Two artificial intelligence (AI) methods were used to examine whether TCM-HPs are capable of distinguishing TCM prescriptions from non-TCM recipes. Two AI systems were trained and tested by using 1161 TCM prescriptions, 11,202 non-TCM recipes, and two separate evaluation methods. These systems correctly classified 83.1-97.3% of the TCM prescriptions, 90.8-92.3% of the non-TCM recipes. These results suggest that TCM-HPs are capable of separating TCM prescriptions from non-TCM recipes, which are useful for formulating TCM prescriptions and consistent with the expected correlation between TCM-HPs and the physicochemical properties of herbal ingredients responsible for producing the collective pharmacological and other effects of specific TCM prescriptions.
Asunto(s)
Prescripciones de Medicamentos/clasificación , Medicamentos Herbarios Chinos/clasificación , Medicamentos sin Prescripción/clasificación , Algoritmos , Inteligencia Artificial , Fenómenos Químicos , Química Farmacéutica , Química Física , Medicina Tradicional ChinaRESUMEN
BACKGROUND AND PURPOSE: Traditional Chinese Medicine (TCM) is widely practised and is viewed as an attractive alternative to conventional medicine. Quantitative information about TCM prescriptions, constituent herbs and herbal ingredients is necessary for studying and exploring TCM. EXPERIMENTAL APPROACH: We manually collected information on TCM in books and other printed sources in Medline. The Traditional Chinese Medicine Information Database TCM-ID, at http://tcm.cz3.nus.edu.sg/group/tcm-id/tcmid.asp, was introduced for providing comprehensive information about all aspects of TCM including prescriptions, constituent herbs, herbal ingredients, molecular structure and functional properties of active ingredients, therapeutic and side effects, clinical indication and application and related matters. RESULTS: TCM-ID currently contains information for 1,588 prescriptions, 1,313 herbs, 5,669 herbal ingredients, and the 3D structure of 3,725 herbal ingredients. The value of the data in TCM-ID was illustrated by using some of the data for an in-silico study of molecular mechanism of the therapeutic effects of herbal ingredients and for developing a computer program to validate TCM multi-herb preparations. CONCLUSIONS AND IMPLICATIONS: The development of systems biology has led to a new design principle for therapeutic intervention strategy, the concept of 'magic shrapnel' (rather than the 'magic bullet'), involving many drugs against multiple targets, administered in a single treatment. TCM offers an extensive source of examples of this concept in which several active ingredients in one prescription are aimed at numerous targets and work together to provide therapeutic benefit. The database and its mining applications described here represent early efforts toward exploring TCM for new theories in drug discovery.
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Bases de Datos Factuales , Prescripciones de Medicamentos/normas , Medicamentos Herbarios Chinos/normas , Inteligencia Artificial , Recolección de Datos , Combinación de Medicamentos , Medicamentos Herbarios Chinos/efectos adversos , Medicamentos Herbarios Chinos/farmacología , MEDLINE , Receptores de Droga/efectos de los fármacos , Receptores de Droga/genética , Reproducibilidad de los ResultadosRESUMEN
Ten multiparous lactating sows were used to investigate whether intramammary infusion of lipopolysaccharides (LPS; Escherichia coli 0111:B4; 2.0 microg/kg of body weight) would affect the circulating concentrations of Ca, P, 25-hydroxyvitamin D (25-OHD), tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and cortisol. The sows were randomly allotted to either control group (control) or LPS-treated group with five individuals per group and were infused with either physiological saline solution or LPS solution. The rectal temperature and udder quarter appearance were recorded at 0 (just before infusion), 1, 3, 7, 12 or 24 h after infusion. Blood samples were taken at 0, 1, 3, 7, 12 or 24 h after infusion. Before infusion, the rectal temperatures of all sows were below 39.2 degrees C. At 3 and 7 h after infusion, the sows in the LPS group had a rectal temperature over 39.4 degrees C. At 24 h after infusion, the rectal temperatures returned to pre-infusion levels. Serum Ca and P concentrations in the LPS group decreased (P < 0.05) after LPS infusion compared with the control group at 1 h after infusion. No significant differences (P > 0.05) in the concentrations of 25-OHD were observed between groups control and LPS at any sampling time. Increased (P < 0.01) concentrations of serum TNF-alpha, IL-6 and cortisol were observed in the LPS group compared with the control group at 3 and 7 h after infusion respectively. In conclusion, the elevation of serum concentrations of TNF-alpha, IL-6 and cortisol and the alterations of circulating concentrations of Ca and P following LPS infusion indicate that the immune system has been activated and immune activation may affect macromineral homeostatic regulation, which might have important implications for metabolic health of lactating sows. Lowered serum Ca and P following immune activation also shows a causative mechanism whereby immune activation increases the risk of secondary disorders such as mastitis-metritis-agalactia syndrome. However, immune activation did not affect circulating concentrations of vitamin D metabolites.
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Citocinas/sangre , Hidrocortisona/sangre , Lipopolisacáridos/administración & dosificación , Mastitis/veterinaria , Enfermedades de los Porcinos/sangre , Animales , Área Bajo la Curva , Calcio/sangre , Calcio/inmunología , Citocinas/inmunología , Femenino , Hidrocortisona/inmunología , Infusiones Intravenosas/veterinaria , Interleucina-6/sangre , Interleucina-6/inmunología , Cinética , Lactancia , Lipopolisacáridos/farmacología , Mastitis/sangre , Fósforo/sangre , Fósforo/inmunología , Distribución Aleatoria , Porcinos , Factor de Necrosis Tumoral alfa/inmunología , Vitamina D/análogos & derivados , Vitamina D/sangreRESUMEN
Text-based search is widely used for biomedical data mining and knowledge discovery. Character errors in literatures affect the accuracy of data mining. Methods for solving this problem are being explored. This work tests the usefulness of the Smith-Waterman algorithm with affine gap penalty as a method for biomedical literature retrieval. Names of medicinal herbs collected from herbal medicine literatures are matched with those from medicinal chemistry literatures by using this algorithm at different string identity levels (80-100%). The optimum performance is at string identity of 88%, at which the recall and precision are 96.9% and 97.3%, respectively. Our study suggests that the Smith-Waterman algorithm is useful for improving the success rate of biomedical text retrieval.
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Algoritmos , Almacenamiento y Recuperación de la Información/métodos , Procesamiento de Lenguaje Natural , Bases de Datos Bibliográficas , Reconocimiento de Normas Patrones Automatizadas , Plantas MedicinalesRESUMEN
Traditional Chinese medicine (TCM) has been widely practiced and is considered as an alternative to conventional medicine. TCM herbal prescriptions contain a mixture of herbs that collectively exert therapeutic actions and modulating effects. Traditionally defined herbal properties, related to the pharmacodynamic, pharmacokinetic and toxicological, as well as physicochemical properties of their principal ingredients, have been used as the basis for formulating TCM multi-herb prescriptions. These properties are used in this work to develop a computer program for predicting whether a multi-herb recipe is a valid TCM prescription. This program is based on a statistical learning method, support vector machine (SVM), and it is trained by using 575 well-known TCM prescriptions and 1961 non-TCM recipes generated by random combination of TCM herbs. Testing results by using 72 well-known TCM prescriptions and 5039 non-TCM recipes showed that 73.6% of the TCM prescriptions and 99.9% of non-TCM recipes are correctly classified by this system. A further test by using 48 TCM prescriptions published in recent years found that 68.7% of these are correctly classified. These accuracies are comparable to those of SVM classification of other biological systems. Our study indicates the potential of SVM for facilitating the analysis of TCM prescriptions.
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Diseño de Fármacos , Medicamentos Herbarios Chinos/efectos adversos , Medicamentos Herbarios Chinos/farmacología , Programas Informáticos , Química Farmacéutica , Prescripciones de Medicamentos , Humanos , Medicina Tradicional ChinaRESUMEN
Freeze-dried ileal effluent (1% wt/vol) from cannulated pigs fed rice-based diets with the inclusion of either animal protein (CON), animal protein plus potato starch (PS), animal protein plus sugar beet pulp (SBP), or animal protein plus wheat bran (WB) was incubated anaerobically at pH 6.0 in fermenters containing 5% (wt/vol) fecal slurry comprising mineral salts medium and 50 g/L of fresh feces from pigs fed the same diets as the cannulated pigs. Samples were collected from the fermenters at 0, 2, 4, 12, 24, and 48 h during in vitro fermentation for measuring nonstarch polysaccharides (NSP), starch, and short-chain fatty acids (SCFA). Results showed that the major SCFA produced were acetate, propionate, and butyrate. The inclusion of soluble dietary fiber (diet SBP) caused the highest concentrations of acetate, propionate, butyrate, and total SCFA, whereas the increase in the production of propionate resulting from the addition of insoluble dietary fiber (diet WB) only occurred at the initial stages during 48 h in vitro fermentation. At all sampling occasions (except for 4 h), the levels of butyrate were increased (P < 0.01) by resistant starch compared with fiber sources, showing that a higher level of butyrate can be achieved through microbial fermentation by potato starch. Lowered (P < 0.05) butyrate concentrations were observed with diet WB during in vitro fermentation. With the inclusion of fiber sources, the energy originating from SCFA was similar to that from NSP disappearance, whereas the values were lower (P < 0.05) from NSP disappearance than for SCFA generated without fiber sources supplemented. We conclude that more substrate is available in ileal effluent with the addition of soluble dietary fiber, and an increased level of butyrate could be achieved through microbial fermentation by resistant starch.
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Fibras de la Dieta/metabolismo , Ácidos Grasos Volátiles/biosíntesis , Íleon/metabolismo , Almidón/metabolismo , Porcinos/metabolismo , Animales , Bacterias Anaerobias/metabolismo , Carbohidratos de la Dieta/análisis , Carbohidratos de la Dieta/metabolismo , Fibras de la Dieta/análisis , Digestión , Ácidos Grasos Volátiles/análisis , Heces/microbiología , Fermentación , Técnicas In Vitro , Masculino , Distribución Aleatoria , Almidón/análisisRESUMEN
BACKGROUND: Antibiotic resistance is recognized as an increasing problem in China. It is widely believed that because antibiotics are available without a prescription, changing physician prescribing behaviors will not decrease inappropriate usage. This study identified the sources of antibiotics and the important influence that physicians have on antibiotic use by children in one region of China. METHODS: Trained medical professionals surveyed parents of children attending several kindergartens in urban Beijing and rural Gu'An, Hebei County. Parents completed a questionnaire concerning the children's recent illnesses, care-seeking patterns and antibiotic use. The team also observed hospital- and non-hospital-based pharmacy purchases of antibiotics for children, assessed the proportion accompanied by a prescription and then interviewed parents about factors influencing those purchases. RESULTS: Of 241 urban and 143 rural kindergarten parents, 76 to 82% usually obtained children's antibiotics from a hospital pharmacy (with a prescription). For 84% the first source of care was usually a physician (primarily western medicine, sometimes traditional Chinese medicine). Only 5% of antibiotics were obtained from independent vendors without prior physician consultation. Among 229 observed antibiotic purchases 72% occurred at hospital-based facilities, even after longer observation times at nonhospital pharmacies. Prescriptions accompanied all hospital-based antibiotic purchases, contrasting with 18% of nonhospital transactions (P < 0.001). Together 86% of parents self-reported that the observed purchase stemmed from a doctor's recommendation. CONCLUSIONS: Doctors directly and indirectly controlled the majority of antibiotic usage for childhood illnesses in Beijing and Gu'An (Hebei County). Physician education and implementation of treatment guidelines might substantially reduce inappropriate antimicrobial usage and help prevent antimicrobial resistance in this region.
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Antibacterianos/uso terapéutico , Enfermedades Transmisibles/tratamiento farmacológico , Rol del Médico , Pautas de la Práctica en Medicina/normas , Niño , Preescolar , China , Farmacorresistencia Microbiana , Humanos , Población Rural , Encuestas y Cuestionarios , Población UrbanaRESUMEN
The article describes data collected using Pollock's Health-Related Hardiness Scale (HRHS) in two cultural groups of nurses. The purposes of the study were to verify the workability of the HRHS cross-culturally and to compare the effects of health hardiness in nurses in the United States and Taiwan. A total of 163 American and 615 Taiwanese nurses participated and answered a self-administered questionnaire by using Pollock's 34-item HRHS. Psychometric analyses identified two factors of hardiness that are different from Pollock's factors. Pollock's findings were verified, and the HRHS is valid for measuring hardiness constructs as exemplified by the strong factor loading obtained from this study, which ranged from 0.43 to 0.68 for American nurses and 0.47 to 0.68 for Taiwanese nurses.
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Adaptación Psicológica , Actitud Frente a la Salud/etnología , Control Interno-Externo , Enfermeras y Enfermeros/psicología , Personalidad , Encuestas y Cuestionarios/normas , Comparación Transcultural , Estudios Transversales , Análisis Factorial , Humanos , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados , Taiwán , Estados UnidosRESUMEN
N-methyl-D-aspartic acid (NMDA) receptors transiently transfected into mammalian HEK-293 cells were characterized with subunit-specific antibodies and electrophysiological recordings. Deactivation time course recorded in response to fast-glutamate pulses were studied in isolated and lifted cells, as well as in outside-out membrane patches excised from cells expressing recombinant NR1 subunits in combination with the NR2A, NR2B, NR2C, or NR2D NMDA receptor subunits. Transfected cells were preidentified by the fluorescence emitted from the coexpressed Aequorea victoria jellyfish Green Lantern protein. Currents generated by NR1/NR2A channels displayed double exponential deactivation time course being faster than that in NR1/NR2B or NR1/NR2C channels. However, a large decay variability was observed within each cotransfection, suggesting that mechanisms additional to subunit composition may also regulate deactivation time course. NR1/NR2D channels displayed slowly deactivating currents. Channel deactivation was fast and comparable among receptors obtained by cotransfecting five distinct spliced variants of the NR1 subunit, each with the NR2A subunit. Additionally, recovery from desensitization was slower for NR1/NR2B than for NR1/NR2A channels. The average deactivation time course of responses to brief L-glutamate applications in cells where NR1/NR2A/NR2B cDNAs were cotransfected at variable ratio was intermediate between those of the NR1/NR2A and NR1/NR2B channels. Although immunocytochemical evidence indicates that the majority of cells are cotransfected by all plasmids in triple transfection, our experimental condition did not allow for a tight control of the expression of NMDA receptor subunits. This produced the result that many cells were characterized by deactivation time course and haloperidol sensitivities of separate NR1/NR2A and NR1/NR2B subunit heteromers. We also speculate on the possible formation of channels resulting from the coassembly in the same receptor of NR1/NR2A/NR2B subunits from a minority of cells that gave responses to brief application of L-glutamate characterized by slow deactivation time course and decreased haloperidol sensitivity.
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Ácido Cisteico/farmacología , Ácido Glutámico/farmacología , Receptores de N-Metil-D-Aspartato/fisiología , Proteínas Recombinantes de Fusión/fisiología , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Línea Celular , ADN Complementario/genética , Técnica del Anticuerpo Fluorescente Indirecta , Genes Reporteros , Haloperidol/farmacología , Humanos , Riñón , Potenciales de la Membrana/efectos de los fármacos , Técnicas de Placa-Clamp , Conformación Proteica , Multimerización de Proteína , Empalme del ARN , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/inmunología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/efectos de los fármacos , Proteínas Recombinantes de Fusión/inmunología , TransfecciónRESUMEN
In this study, we have found that IGF-binding protein-3 (IGFBP-3) in calf serum added to tissue culture medium is degraded by cultured FRTL-5 cells and a major 31 kDa fragment of IGFBP-3 is produced. When FRTL-5 rat thyroid cells were cultured in 6H medium (modified F-12M medium containing TSH, insulin, hydrocortisone, somatostatin, transferrin, and glycyl-histidyl-lysine) containing 5% calf serum, both 44-46 and 31 kDa IGFBPs were found in conditioned medium by ligand blot analysis using 125I-labelled IGF-II. However, predominantly the 44-46 kDa IGFBP was detected in unconditioned 6H medium containing 5% calf serum. When calf serum in the media was replaced by human serum similar results were obtained, and the 44-46 kDa and 31 kDa IGFBPs were recognized using a human IGFBP-3 antibody following Western blot analysis. FRTL-5 cells secreted only small amounts of an endogenous 29 kDa IGFBP, thought to be IGFBP-5. To separate the 31 kDa fragment of IGFBP-3 from the endogenous IGFBP-5, culture media were fractionated by concanavalin-A-Sepharose chromatography and aliquots of both flow-through and eluate from the column were analyzed by ligand blotting. A 31 kDa IGFBP was found in the eluate fractions from concanavalin-A-Sepharose chromatography following the separation of conditioned 6H medium supplemented with calf serum, suggesting that this species was an N-linked glycoprotein and could be derived from the degradation of serum IGFBP-3 by FRTL-5 cells. Using a modified zymographic assay, we examined whether the degradation of IGFBP-3 could depend on the cell membrane. Confluent FRTL-5 cells were washed with PBS and overlaid with liquid agarose solution. After the agarose had solidified, unconditioned 6H medium containing 5% calf serum was incubated with the cells at 37 degrees C for 16 h. Both 44-46 and 31 kDa IGFBP species were found in the overlying, conditioned medium by ligand blot. However, the 31 kDa IGFBP was not found in medium in the absence of FRTL-5 cells, and no IGFBP could be found in serum-free conditioned medium from agarose-covered FRTL-5 cells. This suggests that the 44-46 kDa IGFBP-3 in serum was degraded to yield a 31 kDa fragment, while any endogenous IGFBP-5 could not pass out of the agarose. The degradation of 44-46 kDa IGFBP-3 in the modified zymographic assay was inhibited by phenylmethylsulfonyl fluoride, EDTA, and aprotinin, but not by leupeptin. In summary, these results indicated that IGFBP-3 in calf serum added to culture medium could be degraded by FRTL-5 cells and that this may involve calcium-dependent serine proteases.
Asunto(s)
Endopeptidasas/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Glándula Tiroides/enzimología , Animales , Western Blotting , Bovinos , Medios de Cultivo Condicionados/química , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/análisis , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/análisis , Ratas , Células Tumorales CultivadasRESUMEN
The article reports a study describing nurses' attitudes, concerns, and fear of acquired immunodeficiency syndrome (AIDS). A convenience sample consisting of 376 nurses in a mid-Atlantic state was drawn. An 84-item questionnaire was used to collect the data. Seven factors were derived from the subjects' responses using the Fear of AIDS Scale II: opinion and AIDS policy, blood and physical closeness to patients with AIDS, punishing the homosexual, ethics of care. "Who would care for me?" financial burden, and self-worth. Fear of AIDS Scale II scores ranked the highest whenever "self" was involved with AIDS issues or blood and physical closeness to a person with AIDS. There was a parallel increasing relationship between concern about contracting AIDS from patients and the fear of AIDS. A number of other significant correlations emerged from the study.
Asunto(s)
Docentes de Enfermería , Miedo , Infecciones por VIH/enfermería , Conocimientos, Actitudes y Práctica en Salud , Personal de Enfermería en Hospital , Adulto , Femenino , Infecciones por VIH/transmisión , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional , Masculino , Persona de Mediana Edad , Investigación Metodológica en Enfermería , Personal de Enfermería en Hospital/educación , Personal de Enfermería en Hospital/psicología , Encuestas y Cuestionarios , Estados UnidosRESUMEN
The article reports a study investigating whether a positive relationship exists between a battered women's perceptions of loss and her perceptions of health. The study further investigated whether a period of time away from the abusive situation would change the battered women's perceptions of loss and her perceptions of health. A convenience sample of 20 women who had experienced battering and abuse and had sought help at a protective shelter was studied. Questionnaires on perception of loss, health response, and demographics were used for the collection of data. The findings indicated that a significant relationship exists between a battered women's perceptions of loss and her perception of health. Perceptions of loss and health were shown to decline after a period of 5 days away from the abusive situation. Additional qualitative data obtained from in-depth interviews were also found to be consistent with the quantitative results and supported the literature documented in this study.