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1.
Br Poult Sci ; 61(6): 695-702, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32551967

RESUMEN

1. Four experiments were conducted to determine the 4th limiting amino acid (AA) in maize-soybean meal-based diets. 2. Deletion assay methodology was used to quantify performance and carcase trait responses to potential deficiencies in essential and conditionally essential AA caused by reductions in dietary crude protein of maize-soybean meal-based diets from 202.9 to 186.5 g/kg. 3. The deletion of Val, Phe and Gly + Pro resulted in negative effects on live performance and carcase traits for male broilers, whereas AA deletion only affected wing weights for females with no response on live performance. 4. Further experimentation could not duplicate a response to Phe or Pro in male broilers. 5. Valine was identified as the potential 4th limiting AA in maize-soybean meal-based diets and was not found to be co-limiting with Ile.


Asunto(s)
Alimentación Animal , Pollos , Aminoácidos , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Pollos/genética , Dieta/veterinaria , Dieta con Restricción de Proteínas/veterinaria , Proteínas en la Dieta , Femenino , Masculino , Glycine max
2.
Science ; 215(4537): 1264-5, 1982 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-17757544

RESUMEN

7-Hydroxy-6,7-dihydro-5H-pyrolizine-1-carboxaldehyde is the major volatile component of the scent organs in males of two species of Creatonotos (Lepidoptera, Arctiidae). The biosynthesis of this presumed pheromone depends on the presence of pyrrolizidine alkaloids in plants that are ingested by the larvae. In addition, these secondary plant substances control the morphogenesis of the scent organs. This morphogenetic effect of an alkaloid has not been observed previously.

3.
Biochim Biophys Acta ; 970(2): 212-21, 1988 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-3382699

RESUMEN

The synthetic antiglucocorticoid RU 38486 interacts with cardiac cytoplasmic glucocorticoid receptors and competes for in vitro binding with the potent agonist triamcinolone acetonide. In addition to binding to receptors with high affinity, RU 38486 also facilitates the in vitro conformational change in the receptor which is a consequence of the physiologically relevant activation step during which the receptor is converted from a non DNA- to a DNA-binding form. This ability of RU 38486 to promote receptor activation is reflected by both the appropriate shift in the elution profile of [3H]RU 38486-receptor complexes from DEAE-cellulose as well as by an increased binding of these complexes to DNA-cellulose. Although less effective than triamcinolone acetonide, RU 38486 promotes in vitro receptor activation under a variety of experimental conditions, including incubation of labeled cardiac cytosols at 25 degrees C for 30 min or at 15 degrees C for 30 min in the presence of 5 mM pyridoxal 5'-phosphate. Once thermally activated, the cardiac [3H]triamcinolone acetonide and [3H]RU 38486-receptor complexes bind to nonspecific DNA-cellulose with the same relative affinities, as evidenced by the fact that 50% of both activated complexes are eluted at approx. 215-250 mM NaCl. Thus, this pure antiglucocorticoid does promote, at least to some extent, many of the crucial in vitro events including high-affinity binding, activation, and DNA binding which have been shown to be required to elicit a physiological response in vivo.


Asunto(s)
Estrenos/farmacocinética , Glucocorticoides/antagonistas & inhibidores , Miocardio/metabolismo , Receptores de Glucocorticoides/efectos de los fármacos , Triamcinolona Acetonida/farmacocinética , Animales , Biotransformación , Celulosa/análogos & derivados , Celulosa/metabolismo , Citoplasma/metabolismo , ADN/análogos & derivados , ADN/metabolismo , Glucocorticoides/metabolismo , Calor , Masculino , Mifepristona , Conformación Proteica/efectos de los fármacos , Ratas , Ratas Endogámicas , Triamcinolona Acetonida/metabolismo
4.
Mol Endocrinol ; 9(7): 838-47, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7476967

RESUMEN

T47D human breast carcinoma cells and the chicken oviduct were used to study the structure of the nonactivated progesterone receptor (PR) complex. Immunoprecipitation of PR (B form) from cytosol extracts was performed using monoclonal antibody PR6, a cross-reactive antibody prepared to chicken PR. Analysis of the PR complex by sodium dodecyl sulfate gels and Western immuno-blotting revealed the presence of several specific copurifying proteins. Consistent with previous reports, the two heat shock proteins, hsp90 and hsp70, were shown to be present. A third 59-kilodalton (kDa) protein observed previously was confirmed to be p59 (also called hsp56 or FKBP52), which has been shown to bind the immunosuppressant drug FK506. Two additional PR-associated proteins were observed that had not been previously recognized with human PR. These have molecular masses of 54-kDa and 23-kDa and have been shown by Western blotting to be related to the proteins p54 and p23 that are associated with chicken PR. P23 is a novel protein of unknown function and p54 or FKBP54 has been recently shown to be another FK506-binding protein related to p59. Finally, the cyclosporin A-binding protein, CyP-40, could be detected in isolated chicken PR complexes and in PR complexes that were reconstituted in vitro, but this protein was not detected in human PR complexes, which are less stable than chicken PR complexes in cytosol extracts. The functional significance of FK506 and cyclosporin A-binding proteins to hormone action was tested using a T47D cell line that contained a progestin reporter gene, MMTV-CAT. Treatment with cyclosporin A had no effect on the basal level of CAT expression, but it caused a dramatic increase in the sensitivity and magnitude of the response to the synthetic progestin, R5020. The enhanced response elicited by drug treatment was blocked by the antiprogestin RU486 indicating that this effect was receptor-mediated. While cyclosporin A enhanced progestin action in T47D cells, it inhibited a PR/reporter gene system in L cells. The drugs FK506 and rapamycin had no effect on progestin action in T47D cells, but they stimulated glucocorticoid action in T47D cells. Thus, the effects of these immunosuppressant drugs vary with the cell type and hormonal system that is tested. Whether these drug effects relate directly to the immunophilins bound in receptor complexes remains unknown.


Asunto(s)
Proteínas Portadoras/metabolismo , Ciclosporina/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Choque Térmico/metabolismo , Inmunosupresores/metabolismo , Agregación de Receptores , Receptores de Progesterona/metabolismo , Tacrolimus/metabolismo , Animales , Neoplasias de la Mama , Carcinoma , Pollos , Ciclosporina/farmacología , Técnicas de Transferencia de Gen , Humanos , Inmunosupresores/farmacología , Ratones , Receptores de Progesterona/genética , Tacrolimus/farmacología , Proteínas de Unión a Tacrolimus , Células Tumorales Cultivadas
5.
Braz J Biol ; 65(3): 431-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16341421

RESUMEN

This paper reports on ant and termite species inhabiting the mounds (murundus) found in three wetland sites in Santo Antonio da Patrulha. Ants and termites were found in 100% of the mounds of two sites and in 20% of those in the third site. Colonies of Camponotus fastigatus were found inhabiting all the mounds, while colonies of Brachymyrmex sp., Linepithema sp., Pheidole sp., and/or Solenopsis sp. were collected in less than 30% of the mounds. In the mounds of the three sites, colonies of Anoplotermes sp. and/or Aparatermes sp. termites were found together with the ant colonies. Another cohabiting termite species, Cortaritermes sp., was found only in the mounds of one site. The results suggest that C. fastigatus is the species building the mounds, with the other species, whether ants or termites, being the inquilines.


Asunto(s)
Hormigas/fisiología , Isópteros/fisiología , Animales , Conducta Animal/fisiología , Brasil , Ecosistema
6.
Metabolism ; 47(1): 63-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9440479

RESUMEN

The glycoprotein laminin, a cross-shaped complex of three genetically different polypeptide chains, is a structural component of the capillary basement membrane. Serum laminin concentrations of healthy controls (n = 60) and adult type I diabetic patients (n = 170) were not age-dependent. Laminin was correlated with hemoglobin A1 (HbA1) values in normoalbuminuric patients (rs = .33, P < .0005, n = 116). Type I diabetic patients without nephropathy or retinopathy in good metabolic control had normal laminin levels. However, increasing stages of microangiopathy were associated with higher laminin levels. The molecular size distribution of serum laminin of control subjects (n = 4) and type I diabetic patients (n = 15) was analyzed by molecular-sieve chromatography. Laminin was eluted in two peaks with a molecular mass of 900 and 300 kd, most likely representing intact laminin and its P1 fragment, respectively. The areas of the two peaks were determined by two-gaussian function fitting. In patients without microangiopathy in poor metabolic control, an increase in the high-molecular weight (HMW) fraction could be detected as compared with healthy subjects and patients with acceptable metabolic control. Furthermore, the HMW laminin fraction and the ratio between the areas of the first and second peak increased with the stage of nephropathy (P < .001, Jonckheere-Terpstra test). These results provide evidence that (1) laminin concentration is increased in chronic hyperglycemia, (2) laminin may be a marker of microangiopathic lesions, and (3) elevated laminin levels may reflect an increased synthesis and/or a defective incorporation of laminin into the capillary basement membrane.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Angiopatías Diabéticas/sangre , Laminina/sangre , Adolescente , Adulto , Anciano , Membrana Basal/metabolismo , Cromatografía en Gel , Nefropatías Diabéticas/sangre , Retinopatía Diabética/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Hiperglucemia/sangre , Laminina/química , Masculino , Persona de Mediana Edad , Peso Molecular
7.
Am J Med Sci ; 319(2): 79-83, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10698090

RESUMEN

BACKGROUND: The prototypic acute phase reactant, C-reactive protein (CRP), is a serum soluble, cyclic pentameric protein, the concentration of which increases markedly within hours of any tissue-damaging, inflammatory event. However, upon dissociation of its pentameric quaternary structure, CRP subunits undergo a spontaneous and irreversible conformational change. The resulting molecule, termed modified CRP or mCRP, has reduced aqueous solubility and a propensity to aggregate into a matrix-like lattice structure. METHODS: Using monoclonal antibodies, normal human tissues were immunohistochemically screened for the presence of CRP as well as mCRP antigens. RESULTS: Significant levels of mCRP were detected in the walls of blood vessels associated with normal human tissues. These data indicate that mCRP is a naturally occurring form of CRP and that it is a tissue-based rather than serum-based molecule. SIGNIFICANCE: This report describes the localization of a stable form of CRP, mCRP, in blood vessels associated with normal human tissues.


Asunto(s)
Arterias/química , Proteína C-Reactiva/análisis , Endocardio/química , Pulmón/química , Anticuerpos Monoclonales , Antígenos/análisis , Proteína C-Reactiva/inmunología , Humanos , Inmunohistoquímica , Túnica Íntima/química , Túnica Media/química
8.
Acta Cytol ; 22(1): 43-5, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-274889

RESUMEN

This is a case report of a patient with diffuse multiple myeloma where atypical plasma cells were first discovered on routine blood and cervico-vaginal smears. Subsequent examination of a small endocervical mass and of the bone marrow revealed invasion by malignant plasma cells. Lytic bone lesions and extensive multiple organ system involvement developed despite chemotherapy and the patient expired five months after diagnosis. This case demonstrates that cervical smears, like other cytologic preparations, may contain malignant plasma cells and illustrates the importance of recognizing these cells.


Asunto(s)
Mieloma Múltiple/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad
9.
Cad Saude Publica ; 17(2): 439-45, 2001.
Artículo en Portugués | MEDLINE | ID: mdl-11283775

RESUMEN

The second semester of 1999 was a transition period for the implementation of the Special Indigenous Health District on the Xapecó Indigenous Reserve in western Santa Catarina State. The health clinic in the main village provided treatment with a staff including a general practitioner/obstetrician, pediatrician, dentist, nurse, two nursing assistants, and four nursing technicians. This paper presents the preliminary results of research on the organization of these health care services, their use by the community, and the health/disease profile of the Kaingáng, using patient files as the source of information. In September 1999, a total of 222 Indians were treated (children and adults), 50.5% of whom residing in the main village. Among the Indians ages 0 to 14 years, infectious and parasitic diseases were the most frequent, supporting the idea that the Kaingáng have precarious sanitary and nutritional conditions. Use of the clinic by adults was more varied, since of the 116 who appeared for consultation, 27 were pregnant women (out of a total of 86 women). In addition, prescriptions were written up for children and adults in 85.0% and 81.8% of the consultations, respectively.


Asunto(s)
Atención a la Salud/organización & administración , Servicios de Salud del Indígena/organización & administración , Indígenas Sudamericanos , Morbilidad , Adolescente , Adulto , Anciano , Brasil/epidemiología , Niño , Preescolar , Atención a la Salud/estadística & datos numéricos , Femenino , Servicios de Salud del Indígena/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Embarazo
10.
Braz J Biol ; 64(1): 33-9, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15195362

RESUMEN

Richness and diversity of ant species are related to environmental factors such as vegetation, soil, presence of heavy metals, and insecticides, which allow the use of the assemblage members as terrestrial indicators of environmental conservation status. This study presents the results of ground ants surveyed in Minas do Camaquã in the municipality of Cacapava do Sul (Camaquã Basin), State of Rio Grande do Sul. Collections were performed in four sites, which high levels of copper in the soil, three of which--a mine, a liquid reject, and a solid reject-, had sparse or no plant cover, and one site where Pinus has been used for rehabilitation. Parque das Guaritas was the control site, since it presented normal levels of copper and a dense savanna cover. For each site, three transect lines extending 100 m were draw, and at each 10 m sardine baits were distributed; after two hours the ants present were collected. Hand collections in all five sites were performed during one hour (capture effort). A total of 51 species belonging to 17 genera were collected. The control site was the richest in ant species (r = 45). Sites with high level of copper and poor plant cover presented the lowest richness: mine (r = 14), solid reject (r = 15), and liquid reject (r = 16). In contrast, the site planted with Pinus presented an increment in richness (r = 24) of ground-dwelling ants, suggesting a reahabilitation process.


Asunto(s)
Hormigas/clasificación , Cobre/análisis , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Animales , Ambiente , Minería , Dinámica Poblacional
11.
Braz J Biol ; 63(2): 301-6, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-14509852

RESUMEN

The control of Acromyrmex leaf-cutting ants is necessary due to the severe damage they cause to diverse crops. A possibility was to control them using the bacterium Bacillus thuringiensis (Bt) that characteristically produces insecticidal crystal proteins (ICPs). The ICPs have been effective in controlling lepidopterans, dipterans, and coleopterans, but their action against hymenopterans is unknown. This paper describes an attempt to isolate Bt from ants of two Acromyrmex species, to evaluate its pathogenicity towards these ants, and to test isolates by PCR. Bacterial isolates of Bt obtained from A. crassispinus and A. lundi have been assayed against A. lundi in the laboratory. The bioassays were carried out in BOD at 25 degrees C, with a 12-hour photoperiod, until the seventh day after treatment. The Bt isolates obtained were submitted to total DNA extraction and tested by PCR with primers specific to cry genes. The results showed Bt presence in 40% of the assessed samples. The data from the in vivo assays showed a mortality rate higher than 50% in the target population, with the Bt HA48 isolate causing 100% of corrected mortality. The PCR results of Bt isolates showed a magnification of DNA fragments relative to cry1 genes in 22% of the isolates, and cry9 in 67%. Cry2, cry3, cry7, and cry8 genes were not detected in the tested samples, and 22% had no magnified DNA fragments corresponding to the assessed cry genes. The results are promising not only regarding allele identification in new isolates, but also fort the assays aimed at determining the Bt HA48 LC50's, which can eventually be applied in controlling of Acromyrmex leaf-cutting ants.


Asunto(s)
Hormigas/microbiología , Bacillus thuringiensis/patogenicidad , Control Biológico de Vectores , Animales , Bacillus thuringiensis/aislamiento & purificación , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/farmacología , Bioensayo , Cartilla de ADN , Reacción en Cadena de la Polimerasa
12.
Braz J Biol ; 61(4): 667-78, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12071324

RESUMEN

The breeding structure of both colony and population of social insects can be examined by genetic analysis. Colonies of the leaf-cutting ants Acromyrmex heyeri and A. striatus (Myrmicinae, Attini) were thus analyzed for isoenzyme systems MDH, a-GPDH, and AMY to describe genotype variability and social structure. A total of five loci were investigated (three for amylase and one for each other system). Ninety-seven colonies of A. heyeri and 103 of A. striatus were sampled in different localities in Southern Brazil (State of Rio Grande do Sul). The genotypes found show the occurrence of monogyny and polygyny associated or not with polyandry, which indicates that the social organization is colony-specific. The polygyny and polyandry observed are likely to be responsible for the great genotypic diversity of the colonies. The average inbreeding coefficient per colony was higher in A. striatus than in A. heyeri, which may reflect the different patterns of production of sexual individuals and nuptial flight of those two species.


Asunto(s)
Hormigas/genética , Variación Genética , Jerarquia Social , Animales , Hormigas/enzimología , Brasil , Femenino , Frecuencia de los Genes , Genotipo , Isoenzimas/análisis , Isoenzimas/genética , Masculino , Polimorfismo Genético , Conducta Sexual Animal
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