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1.
Osteoporos Int ; 28(2): 559-566, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27650642

RESUMEN

Bone mineral density (BMD) sometimes cannot be improved by long-term bisphosphonate (BP) therapy in osteoporosis (OP). This study showed that lumbar as well as hip BMD significantly increased after denosumab treatment in patients not responsive to BPs. Thus, denosumab may be a strong OP treatment option for BP-unresponsive patients. INTRODUCTION: BMD sometimes cannot be improved by long-term BP therapy. METHODS: We administered denosumab to osteoporotic patients with a poor response to BPs who had been taking them for 2 years or longer. Ninety-eight women with BP-poor responsive OP were enrolled in this study. Mean (standard deviation [SD]) age was 71.2 (6.9) years and mean (SD) duration of BP treatment was 59.9 (34.3) months. We distinguished BP responders from non-responders based on changes in BMD values at denosumab commencement (baseline) from 2 years beforehand. RESULTS: There were no significant differences in age, duration of BP use, bone turnover markers, or BMD at baseline between the groups. Prior to denosumab, BMD had increased significantly in responders and decreased significantly in non-responders. Bone turnover markers had decreased significantly at 4 months of denosumab treatment (P < 0.001) and lumbar and hip BMD were significantly increased at 1 year of therapy in both groups (P < 0.001). Simple correlation coefficients were -0.337 for lumbar and -0.339 for hip BMD changes (both P = 0.001) before and after denosumab treatment. Both at the lumbar spine and hips, decreased BMD before denosumab therapy was significantly associated with an increase in BMD at 1 year of treatment (spine, t value = -3.502, P = 0.001, R = 0.113; hip, t value = -3.526, P = 0.001, R = 0.115). CONCLUSIONS: These results suggest that denosumab may be a strong OP treatment option for BP-unresponsive patients.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Denosumab/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Difosfonatos/uso terapéutico , Sustitución de Medicamentos , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Vértebras Lumbares/fisiopatología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Insuficiencia del Tratamiento , Resultado del Tratamiento
2.
J Dairy Sci ; 99(2): 933-946, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26686731

RESUMEN

In this study, we identified a strain of lactic acid bacteria (LAB) that induces high levels of IL-10 production by immune cells, and evaluated the ability of the strain to suppress chronic inflammation and ameliorate metabolic disorders in in vitro and in vivo models. Among a collection of LAB strains, Lactobacillus plantarum strain OLL2712 (OLL2712) induced the highest levels of IL-10 production in mouse-derived dendritic cells and peritoneal macrophages. The anti-inflammatory effects of this strain were evaluated using a co-culture system comprising RAW 264.7 and 3T3-L1 cells. We also administered heat-killed OLL2712 to obese and type 2 diabetic KKAy mice for 3 wk to evaluate the in vivo effects of the strain. The OLL2712 significantly decreased the production of proinflammatory cytokines in vitro. Likewise, the administration of OLL2712 significantly suppressed proinflammatory cytokine levels in both the visceral adipose tissue and the serum of KKAy mice, and reduced serum triglyceride concentrations. The strain also alleviated oxidative stress and adrenaline levels in the serum of KKAy mice. On the other hand, Lactobacillus gasseri strain MEP222804 (a moderate IL-10 inducer) did not ameliorate the systemic inflammation and hyperlipidemia in KKAy mice. Our results suggest that treatment with strong IL-10-inducing LAB has the potential to ameliorate metabolic disorders by suppressing chronic inflammation in the host animal.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Inflamación/terapia , Lactobacillus plantarum/aislamiento & purificación , Lactobacillus plantarum/fisiología , Enfermedades Metabólicas/terapia , Obesidad/complicaciones , Células 3T3-L1 , Animales , Técnicas de Cocultivo , Citocinas/biosíntesis , Células Dendríticas/metabolismo , Heces/microbiología , Femenino , Humanos , Interleucina-10/biosíntesis , Macrófagos Peritoneales/metabolismo , Ratones , Ratones Endogámicos BALB C , Células RAW 264.7
3.
J Hosp Infect ; 146: 160-165, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37301228

RESUMEN

BACKGROUND: During the COVID-19 pandemic, hygiene awareness was increased in communities and hospitals. However, there is controversy regarding whether such circumstances affected the incidence of surgical site infections (SSIs) in the orthopaedic surgical field. AIM: To examine the impact of the COVID-19 pandemic on the incidence of SSIs after orthopaedic surgery. METHODS: The medical records of patients having undergone orthopaedic surgery were extracted from the nationwide surveillance database in Japan. The primary outcomes were the monthly incidences of total SSIs, deep or organ/space SSIs, and SSIs due to meticillin-resistant Staphylococcus aureus (MRSA). Interrupted time series analysis was conducted between pre-pandemic (January 2017 to March 2020) and pandemic (April 2020 to June 2021) periods. RESULTS: A total of 309,341 operations were included. Interrupted time series analysis adjusted for seasonality showed no significant changes in the incidence of total SSIs (rate ratio 0.94 and 95% confidence interval 0.98-1.02), deep or organ/space SSIs (0.91, 0.72-1.15), or SSIs due to MRSA (1.07, 0.68-1.68) along with no remarkable slope changes in any parameter (1.00, 0.98-1.02; 1.00, 0.97-1.02; and 0.98, 0.93-1.03, respectively). CONCLUSIONS: Awareness and measures against the COVID-19 pandemic did not markedly influence the incidence of total SSIs, deep or organ/space SSIs, or SSIs due to MRSA following orthopaedic surgery in Japan.

5.
Science ; 158(3804): 1052-3, 1967 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6054483

RESUMEN

The gamete-shedding substance obtained from the radial nerves induces spawning when it is applied to the gonads of mature starfish in vivo and in vitro. A substance that inhibits the action of this spawning factor is present in both ovary and testis; it has been isolated from testis of Asterina pectinifera and chemically identified as L-glutamic acid.


Asunto(s)
Equinodermos/fisiología , Glutamatos/fisiología , Infertilidad/etiología , Ovario/fisiología , Péptidos/antagonistas & inhibidores , Reproducción , Testículo/fisiología , Animales , Cromatografía en Gel , Cromatografía en Capa Delgada , Femenino , Glutamatos/análisis , Técnicas In Vitro , Rayos Infrarrojos , Masculino , Ovario/análisis , Nervio Radial , Análisis Espectral , Testículo/análisis , Extractos de Tejidos
6.
Poult Sci ; 88(12): 2532-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19903951

RESUMEN

Developmental changes in immunocompetent cells of the gut during the first week posthatch were determined in broiler chicks fed immunobiotic lactic acid bacteria in the form of Lactobacillus jensenii TL2937-, Lactobacillus gasseri JCM1131(T)-, Lactobacillus delbrueckii ssp. bulgaricus NIAIB6-, or L. gasseri TL2919-supplemented diets. The relative weights of spleen and bursa of Fabricius in chicks fed the immunobiotic diets were slightly higher than the control valued at 1 and 3 d of age, with the exception of spleen weight in the L. gasseri JCM1131(T) at 3 d of age, the bursa of Fabricius weight in the L. gasseri JCM1131(T) at 1 and 3 d of age, and bursa of Fabricius weight in the L. gasseri TL2919 group at 1 d of age. There were no significant differences in body and liver weights among the treatments. When chicks were fed the L. jensenii TL2937- or L. gasseri TL2919-supplemented diets, expression of T cell-related mRNA [cluster of differentiation 3 (CD3), interleukin-2 (IL-2), and interferon-gamma (IFN-gamma)] in the foregut was significantly higher than that of control chicks at 3 or 7 d of age. Expression levels of toll-like receptor (TLR) mRNA tended to increase in the foregut of chicks fed the immunobiotic diets, except for the L. delbrueckii ssp. bulgaricus NIAIB6, compared with expression levels in control chicks. The Bu-1 mRNA expression levels in the bursa of Fabricius were not affected by the supplementations with immunobiotic lactic acid bacteria. These results show that immunobiotics, particularly L. gasseri TL2919, might be useful as immunomodulators to stimulate the gut-associated immune system in neonatal chicks, and thereby protect them from disease without decreasing growth performance as a possible substitution of antibiotics.


Asunto(s)
Bolsa de Fabricio/fisiología , Pollos , Dieta/veterinaria , Inmunomodulación/efectos de los fármacos , Tejido Linfoide/fisiología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos , Linfocitos B/fisiología , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica/fisiología , Lactobacillus , Masculino , ARN Mensajero/metabolismo , Linfocitos T/fisiología , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
7.
Bone Joint J ; 100-B(5): 617-621, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29701101

RESUMEN

Aims: Although we often encounter patients with an aortic aneurysm who also have diffuse idiopathic skeletal hyperostosis (DISH), there are no reports to date of an association between these two conditions and the pathogenesis of DISH remains unknown. This study therefore evaluated the prevalence of DISH in patients with a thoracic aortic aneurysm (AA). Patients and Methods: The medical records of 298 patients who underwent CT scans for a diagnosis of an AA or following high-energy trauma were retrospectively examined. A total of 204 patients underwent surgery for an AA and 94 had a high-energy injury and formed the non-AA group. The prevalence of DISH was assessed on CT scans of the chest and abdomen and the relationship between DISH and AA by comparison between the AA and non-AA groups. Results: The prevalence of DISH in the AA group (114/204; 55.9%) was higher than that in the non-AA group (31/94; 33.0%). On multivariate analysis, the factors of AA, male gender, and ageing were independent predictors of the existence of DISH, with odds ratios of 2.9, 1.9, and 1.03, respectively. Conclusion: This study revealed that the prevalence of DISH is higher in patients with an AA than in those without an AA, and that the presence of an AA significantly influenced the prevalence of DISH. Cite this article: Bone Joint J 2018;100-B:617-21.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico por imagen , Hiperostosis Esquelética Difusa Idiopática/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Torácica/epidemiología , Comorbilidad , Femenino , Humanos , Hiperostosis Esquelética Difusa Idiopática/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
9.
J Dairy Sci ; 89(8): 2846-55, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16840600

RESUMEN

Allergic diseases are reported to be caused by a skew in the balance between T helper type 1 and 2 cells. Because some lactic acid bacteria have been shown to stimulate IL-12 (p70) production, which in turn shifts the balance between the T helper type 1 and 2 cell response from the latter to the former, they have the potential to either prevent or ameliorate disease conditions or both. They have therefore been extensively studied in the recent past for their probiotic activities. Nevertheless, much less information is available concerning the microbial factors that determine the strain-dependent ability to affect the production of cytokines. The objectives of our study were first to select potentially probiotic lactobacilli that strongly stimulate cytokine production in vitro, and then to determine whether the selected Lactobacillus strains could suppress antigen-specific IgE production in vivo by using allergic model animals. Finally, our investigation was extended to analyze which bacterial components were responsible for the observed biological activity. Twenty strains of heat-killed lactobacilli isolated from humans were screened for their stimulatory activity for the production of IL-12 (p70) by murine splenocytes in vitro. The results showed that some strains of Lactobacillus plantarum and Lactobacillus gasseri had a higher stimulatory activity for IL-12 (p70) production than the other lactobacilli tested; however, this effect was strain dependent rather than species dependent. Oral administration of the heat-killed strains that showed higher stimulatory activity for IL-12 (p70) production tended to reduce the serum antigen-specific IgE levels in ovalbumin-sensitized BALB/c mice compared with the controls. Among the lactobacilli tested, L. gasseri OLL2809 showed the highest activity in reducing the level of antigen-specific IgE. Furthermore, the stimulatory activity for IL-12 (p70) production was found to be reduced after treating the lactobacilli with N-acetyl-muramidase and to be positively correlated with the amount of peptidoglycan in the cells. The present data suggest that L. gasseri OLL2809 is a good candidate for potential probiotics in terms of either the prevention or amelioration of allergic diseases or both. In addition, the strain-dependent stimulatory activity for IL-12 (p70) production was found to be due, at least in part, to the amount of peptidoglycan present in the cells.


Asunto(s)
Calor , Hipersensibilidad/prevención & control , Lactobacillus/inmunología , Probióticos/uso terapéutico , Animales , Citocinas/biosíntesis , Endopeptidasas/farmacología , Liofilización , Hipersensibilidad/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Interleucina-12/biosíntesis , Lactobacillus/química , Lipopolisacáridos/análisis , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Peptidoglicano/análisis , Bazo/inmunología , Ácidos Teicoicos/análisis
10.
J Dairy Sci ; 89(8): 2873-81, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16840603

RESUMEN

The extracellular polysaccharides (EPS) produced by lactic acid bacteria (LAB) are associated with the rheology, texture, and mouthfeel of fermented milk products, including yogurt. This study investigated the immunomodulatory effects of EPS purified from the culture supernatant of Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1. The crude EPS were prepared from the culture supernatant of L. bulgaricus OLL1073R-1 by standard chromatographic methods, and were fractionated into neutral EPS and acidic EPS (APS). Acidic EPS were further fractionated into high molecular weight APS (H-APS) and low molecular weight APS (L-APS). High molecular weight APS were shown to be phosphopolysaccharides containing D-glucose, D-galactose, and phosphorus. Stimulation of mouse splenocytes by H-APS significantly increased interferon-gamma production, and, moreover, orally administered H-APS augmented natural killer cell activity. Oral administration of yogurt fermented with L. bulgaricus OLL1073R-1 and Streptococcus thermophilus OLS3059 to mice showed a similar level of immunomodulation as H-APS. However, these effects were not detected following administration of yogurt fermented with the starter combination of L. bulgaricus OLL1256 and S. thermophilus OLS3295. We conclude from these findings that yogurt fermented with L. bulgaricus OLL1073R-1, containing immunostimulative EPS, would have an immunomodulatory effect on the human body.


Asunto(s)
Factores Inmunológicos/farmacología , Lactobacillus delbrueckii/metabolismo , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/farmacología , Animales , Medios de Cultivo Condicionados , Fermentación , Galactosa/análisis , Glucosa/análisis , Interferón gamma/biosíntesis , Interleucina-4/biosíntesis , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Peso Molecular , Fósforo/análisis , Polisacáridos Bacterianos/química , Bazo/inmunología , Streptococcus thermophilus/metabolismo , Yogur/microbiología
11.
J Neurosci ; 19(14): 6068-78, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10407043

RESUMEN

A mouse mutation, termed goku, was generated by a gene-trap strategy. goku homozygous mice showed dwarfism, a marked increase in anxiety, and an analgesic effect. Molecular analysis indicated that the mutated gene encodes a puromycin-sensitive aminopeptidase (Psa; EC 3. 4.11.14), whose functions in vivo are unknown. Transcriptional arrest of the Psa gene and a drastic decrease of aminopeptidase activity indicated that the function of Psa is disrupted in homozygous mice. Together with the finding that the Psa gene is strongly expressed in the brain, especially in the striatum and hippocampus, these results suggest that the Psa gene is required for normal growth and the behavior associated with anxiety and pain.


Asunto(s)
Aminopeptidasas/genética , Ansiedad/genética , Enanismo/genética , Dolor/genética , Aminopeptidasas/deficiencia , Aminopeptidasas/metabolismo , Animales , Ansiedad/fisiopatología , Cruzamientos Genéticos , Enanismo/enzimología , Enanismo/fisiopatología , Técnicas Genéticas , Vectores Genéticos , Crecimiento/genética , Heterocigoto , Homocigoto , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos BALB C , Ratones Mutantes Neurológicos , Actividad Motora , Dolor/fisiopatología , Desempeño Psicomotor , Transcripción Genética
12.
Biochim Biophys Acta ; 1007(3): 343-9, 1989 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-2467690

RESUMEN

Embryos of the starfish Asterina pectinifera were examined with regard to their ability to undergo the early events of embryonic development in the presence of formycin, an analogue of adenosine and a reported inhibitor of RNA synthesis. It was shown that in normal embryos the pool of ribonucleoside 5'-triphosphates increased during the period of blastula formation. The increase of the UTP pool was blocked nearly completely by 25 micrograms/ml formycin, and that of the CTP pool was inhibited partially by the same concentration of the drug. On the other hand, the pools of ATP and GTP were the same for both control and formycin-treated embryos. The development of embryos cultured in the presence of 25 micrograms/ml formycin stopped at the early blastula stage. Addition of 100 micrograms/ml each of uridine and cytidine to cultures of embryos that had been placed in 25 micrograms/ml formycin at the onset of blastulation allowed gastrulation to occur, suggesting that the developmental arrest produced by formycin is due primarily to the inhibition of pyrimidine nucleotide biosynthesis.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Formicinas/farmacología , ARN/biosíntesis , Estrellas de Mar/embriología , Animales , Blastocisto/efectos de los fármacos , División Celular/efectos de los fármacos , Formicinas/antagonistas & inhibidores , Formicinas/metabolismo , Nucleótidos de Purina/farmacología , Nucleótidos de Pirimidina/farmacología , Ribonucleótidos/metabolismo , Estrellas de Mar/efectos de los fármacos , Estrellas de Mar/genética
13.
Biochim Biophys Acta ; 958(1): 134-8, 1988 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-3334863

RESUMEN

Six murine monoclonal antibodies were found to react with ganglioside GD2 lactone as well as purified ganglioside GD2. However, the reactivities of these antibodies to various ganglioside lactones were found to differ from each other. Four antibodies only reacted with GD2 lactones, while the other two cross-reacted with lactones of other gangliosides such as GD1b and GT1b.


Asunto(s)
Anticuerpos Monoclonales , Gangliósidos/inmunología , Animales , Química Encefálica , Bovinos , Cromatografía en Capa Delgada , Gangliósidos/aislamiento & purificación , Lactonas , Relación Estructura-Actividad
14.
Endocrinology ; 140(4): 1893-900, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10098529

RESUMEN

Genistein, an isoflavone abundantly present in soybeans, has structural similarity to estrogen, suggesting that genistein may act as a phytoestrogen. To examine the possible role of genistein in hemopoiesis and bone metabolism, female mice were either sham-operated or ovariectomized (OVX), and selected OVX mice were administered genistein for 2-4 weeks (0.1-0.7 mg/day) or 17beta-estradiol (E2; 0.01-0.1 microg/day) s.c., using a miniosmotic pump (Alza Corp., Palo Alto, CA). In OVX mice, uterine weight declined but was completely restored by E2 administration. In contrast, genistein did not demonstrate a reversal of the OVX-induced uterine atrophy. The number of bone marrow cells markedly increased, 2-4 weeks after OVX, and most of these were B220-weakly positive pre-B cells. The increased B-lymphopoiesis was completely restored, not only by E2 but also by genistein administration. In OVX mice, the trabecular bone volume of the femoral distal metaphysis, measured by microcomputed tomography scanning and dual-energy x-ray absorptiometry, was markedly reduced; and genistein restored this, as did E2. These results indicate that genistein exhibits estrogenic action in bone and bone marrow, to regulate B-lymphopoiesis and prevent bone loss, without exhibiting estrogenic action in the uterus. Phytoestrogens may be useful for preventing bone loss caused by estrogen deficiency in females.


Asunto(s)
Linfocitos B/citología , Estrógenos no Esteroides/farmacología , Estrógenos/deficiencia , Genisteína/farmacología , Hematopoyesis/efectos de los fármacos , Isoflavonas , Osteoporosis Posmenopáusica/prevención & control , Animales , Densidad Ósea/efectos de los fármacos , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Estradiol/farmacología , Estrógenos no Esteroides/uso terapéutico , Femenino , Genisteína/uso terapéutico , Humanos , Ratones , Tamaño de los Órganos , Osteoporosis Posmenopáusica/etiología , Ovariectomía , Fitoestrógenos , Preparaciones de Plantas , Glycine max , Útero/anatomía & histología
15.
FEBS Lett ; 302(3): 284-6, 1992 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-1601136

RESUMEN

Halenaquinol sulfate, a hydroquinone sulfate obtained from the sponge Xestospongia sapra, prevented cell membrane fusion events of echinaderm gametes but did not affect early embryonic development of fertilized eggs up to the gastrula stage. However, halenaquinol sulfate inhibited secretion of hatching enzyme, resulting in the formation of gastrulae that were surrounded by the fertilization envelope. Therefore, the use of halenaquinol sulfate offers a unique opportunity to analyze the role of secretory events in complex populations of cells without affecting other cellular functions.


Asunto(s)
Benzo(a)Antracenos/farmacología , Equinodermos/embriología , Fusión de Membrana/efectos de los fármacos , Oocitos/fisiología , Espermatozoides/fisiología , Animales , Blastocisto/efectos de los fármacos , Blastocisto/fisiología , Membrana Celular/fisiología , Fertilización/efectos de los fármacos , Fertilización/fisiología , Gástrula/efectos de los fármacos , Gástrula/fisiología , Masculino , Oocitos/ultraestructura , Espermatozoides/ultraestructura
16.
FEBS Lett ; 350(2-3): 249-52, 1994 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-8070573

RESUMEN

Halenaquinol sulfate, a p-hydroquinone sulfate obtained from a marine sponge, inhibited the activity of eukaryotic DNA polymerases in varying degrees; the Ki values for DNA polymerases, alpha, beta, delta and epsilon were 1.3, 80, 17.5 and 2.0 microM, respectively, whereas it was less effective against E. coli DNA polymerase I. The inhibition occurred competitively with each of dATP and dTTP, but non-competitively with dCTP, dGTP and the template DNA. Thus, halenaquinol sulfate is demonstrated to be a potential inhibitor of DNA polymerases alpha and epsilon, and be a useful tool for analyzing the dNTP binding sites of DNA polymerases.


Asunto(s)
Benzo(a)Antracenos/farmacología , ADN Polimerasa II/antagonistas & inhibidores , Hidroquinonas/farmacología , Inhibidores de la Síntesis del Ácido Nucleico , Animales , Afidicolina/farmacología , Heparina/farmacología , Cinética , Poríferos/química
17.
FEBS Lett ; 369(2-3): 221-4, 1995 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-7544294

RESUMEN

External application of 0.2-100 micrograms/ml albuside B inhibits gastrulation of the starfish (Asterina pectinifera) embryo. Treated embryos retain the late blastula morphology with the vegetal plate. However, the vegetal plate is unreactive to soybean agglutinin, a probe for observing the progenitor cells of the archenteron (mesendoderm) in a normal embryo. The effective period of the treatment is limited from 4 to 6 h after fertilization, a period immediately before the onset of blastulation. RNA synthesis is unaffected during the period of sensitivity. The selectivity of the inhibition shows that albuside B may be a useful tool for studying the mechanisms of mesendoderm differentiation.


Asunto(s)
Gástrula/efectos de los fármacos , Inosina/análogos & derivados , Lectinas de Plantas , Proteínas de Soja , Estrellas de Mar/embriología , Animales , Diferenciación Celular/efectos de los fármacos , Embrión no Mamífero/citología , Embrión no Mamífero/efectos de los fármacos , Inosina/farmacología , Lectinas/farmacología , Morfogénesis , ARN/biosíntesis , Células Madre
18.
Am J Clin Nutr ; 59(2): 409-12, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8310993

RESUMEN

The effects of beta-carotene and ascorbic acid on spontaneous and x-ray-induced appearance of micronuclei (MNs) in human lymphocytes were studied. For 12 d, three groups of healthy volunteers were given beta-carotene-deficient meals containing 100 mg ascorbic acid. There was no supplementation in the first 6 d but, in the last 6 d, the respective groups were given beta-carotene (30 mg), ascorbic acid (300 mg), or placebo. Blood samples were drawn on days 7 and 13 before breakfast, exposed either to x-ray irradiation or left unexposed and were cultured. Lymphocytes containing MNs were then counted. On day 7 the three groups showed comparable MN frequencies. On day 13 lymphocytes containing x-ray-induced MNs became less frequent in the beta-carotene but not the ascorbic acid group. Both before and after the supplementation, the MN frequency of irradiated lymphocytes showed a significant inverse correlation with plasma beta-carotene. These results strongly suggest that beta-carotene protects human lymphocytes from x-ray-induced genetic damage.


Asunto(s)
Ácido Ascórbico/farmacología , Carotenoides/farmacología , Daño del ADN/efectos de los fármacos , Linfocitos/ultraestructura , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Adulto , Ácido Ascórbico/sangre , Carotenoides/sangre , ADN/efectos de los fármacos , ADN/efectos de la radiación , Femenino , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/efectos de la radiación , Micronúcleos con Defecto Cromosómico/efectos de la radiación , Vitamina A/sangre , Vitamina E/sangre , beta Caroteno
19.
Neuropharmacology ; 26(4): 379-84, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2884591

RESUMEN

The effects of bifemelane hydrochloride on neuronal activity in the visual cortex of the cat were studied by microiontophoretic application under methoxyflurane anesthesia. Of 195 neurons examined with both acetylcholine (ACh) and bifemelane, 67 cells (34%) were excited and 7 cells (4%) were inhibited by ACh. The effect of bifemelane was excitatory on 122 neurons (63%), inhibitory on 20 (10%) and unchanged on the rest. In 60 cells out of the above 122 neurons, bifemelane showed a similar discharge pattern to ACh with a slow onset and delayed termination. The bifemelane-induced excitation was, in 18 out of 22 cells, antagonized by atropine (30-40 nA). Also, a potentiation in bifemelane-induced discharges by physostigmine (30-50 nA) was observed in 14 of the 32 cells tested. The firing evoked by ACh (80-100 nA) was potentiated during of after the application of bifemelane (30-40 nA) in 9 out of 29 neurons, which were not excited by bifemelane alone. These results suggest that neuronal discharges produced by bifemelane are induced at least in part, through a muscarinic ACh receptor, although other mechanisms may possibly be involved.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Corteza Visual/efectos de los fármacos , Acetilcolina/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Atropina/farmacología , Gatos , Glutamatos/fisiología , Ácido Glutámico , Fisostigmina/farmacología , Corteza Visual/fisiología
20.
J Med Chem ; 44(24): 4082-91, 2001 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-11708912

RESUMEN

In the joint experimental and computational efforts reported here to obtain novel chemical entities as growth hormone secretagogues (GHSs), a small database of peptides and non-peptides known to have GHS activity was used to generate and assess a 3D pharmacophore for this activity. This pharmacophore was obtained using a systematic and efficient procedure, "DistComp", developed in our laboratory. The 3D pharmacophore identified was then used to search 3D databases to explore chemical structures that could be novel GHSs. A number of these were chosen for synthesis and assessment of their ability to release growth hormone (GH) from rat pituitary cells. Among the compounds tested, those with a benzothiazepin scaffold were discovered with micromolar activity. To facilitate lead optimization, a second program, a site-dependent fragment QSAR procedure was developed. This program calculates a library of chemical and physical properties of "fragments" or chemical components in a known pharmacophore and determines which, if any, of these properties are important for the observed activity. The combined use of the 3D pharmacophore and the results of the site-dependent fragment QSAR analysis led to the discovery and synthesis of a novel series of potent GHSs, a number of which had nanomolar in vitro activity.


Asunto(s)
Hormona del Crecimiento/metabolismo , Tiazepinas/síntesis química , Animales , Bases de Datos Factuales , Diseño de Fármacos , Hormona del Crecimiento/agonistas , Hormona del Crecimiento/química , Técnicas In Vitro , Modelos Moleculares , Imitación Molecular , Adenohipófisis/citología , Adenohipófisis/metabolismo , Relación Estructura-Actividad Cuantitativa , Ratas , Tiazepinas/química , Tiazepinas/farmacología
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