RESUMEN
The nanometer-scale spatial distributions of local thickness or composition of noncrystalline materials are generally measured by spectroscopy with scanning transmission electron microscopy (STEM). Since spectroscopy requires a high electron dose and causes irradiation damage, alternative non-spectroscopic methods are required to measure the local thickness or composition of electron-sensitive noncrystalline materials. Here, we focus on the radial distribution function (RDF) of the electron diffraction of non-crystalline materials. We confirm that the RDF of the electron diffraction obtained by simulation contains information on the thickness and composition. Next, we demonstrate the determination of both thickness and composition from experimentally obtained RDFs. Although some constraints are required, we determine the local thickness and composition of a BaO-SiO2 glass sample by comparing the RDFs of diffraction measured by a high-speed pixelated detector with those of the simulated diffractions. Collaterally, this determination method can improve the quality of STEM images.
RESUMEN
Fertilization is a multistep process requiring spermatozoa with unique cellular structures and numerous germ cell-specific molecules that function in the various steps. In the highly coordinated process of male germ cell development, RNA splicing and polyadenylation help regulate gene expression to assure formation of functional spermatozoa. Male germ cells express tauCstF-64 (Cstf2t gene product), a paralog of the X-linked CstF-64 protein that supports polyadenylation in most somatic cells. We previously showed that loss of tauCstF-64 causes male infertility because of major defects in mouse spermatogenesis. Surprisingly, although Cstf2t(-/-) males produce very few recognizable spermatozoa, some of the spermatozoa produced are motile. This led us to ask whether these Cstf2t(-/-) sperm were fertile. A motile cell-enriched population of spermatozoa from Cstf2t-null males dispersed cumulus cells of cumulus-oocyte complexes normally. However, motile spermatozoa from Cstf2t-null males failed to fertilize cumulus-intact mouse eggs in vitro. In addition, sperm adhesion to the zona pellucida (ZP) of cumulus-free eggs was significantly decreased, indicating tauCstF-64 is required for production of spermatozoa capable of ZP interaction. Acrosomal proteins involved in sperm-ZP recognition, including zonadhesin, proacrosin, SPAM1/PH-20, and ZP3R/sp56, were normally distributed in the apical head of Cstf2t(-/-) spermatozoa. We conclude that tauCstF-64 is required not only for expression of genes involved in morphological differentiation of spermatids but also for genes having products that function during interaction of motile spermatozoa with eggs. To our knowledge, this is the first demonstration that a gene involved in polyadenylation has a negative consequence on sperm-ZP adhesion.
Asunto(s)
Factor de Estimulación del Desdoblamiento/metabolismo , Fertilización/fisiología , Infertilidad Masculina/metabolismo , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/metabolismo , Acrosoma/metabolismo , Análisis de Varianza , Animales , Factor de Estimulación del Desdoblamiento/genética , Células del Cúmulo/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Infertilidad Masculina/genética , Masculino , Ratones , Ratones Noqueados , Motilidad Espermática/fisiología , Zona Pelúcida/metabolismoRESUMEN
The ethanolic extract of the leaves of Tamarindus indicus was investigated for its anti inflammatory and analgesic actions. The anti inflammatory activity was studied using carrageenin induced hind paw edema in rats and analgesic activity using chemical writhing test and tail clip method in mice and tail flick method yin rats. Test drug exhibited significant dose dependent anti inflammatory and analgesic and analgesic actions and found to be not superior to that of acetyl acid.
RESUMEN
In a tribal village in Kerala, India, local volunteers were trained to work in a programme for the primary prevention of tobacco-related cancers and the secondary prevention of common cancers. They gathered data on the use of tobacco and alcohol in a population of some 19,000 people, and identified one or more warning signals of cancer in 430 persons, who were subsequently examined by physicians. Confirmation was obtained of 10 new cancers, 7 recurrent cancers, 46 oral precancerous conditions, and 58 precancers at other sites. The community's awareness of cancer problems increased and the people learnt about the importance of self-examination in the detection of breast cancer and oral cancer.
Asunto(s)
Neoplasias/epidemiología , Voluntarios , Adulto , Técnicos Medios en Salud/educación , Neoplasias de la Mama/prevención & control , Femenino , Humanos , India/epidemiología , Neoplasias Pulmonares/prevención & control , Masculino , Neoplasias de la Boca/prevención & control , Neoplasias/prevención & control , Lesiones Precancerosas/diagnósticoRESUMEN
Malignant Systemic Mastocytosis is a very rare condition. Only about less than 40 well documented cases have been reported as per the available literature. The paper presents the case report of a 54 year old male patient who presented with huge hepatosplenomegaly and abdominal lymphadenopathy. Splenectomy specimen was 17 x 16 x 10 cm size with cut surface studded with numerous tiny 1-2 mm nodules. Histologic sections of spleen showed extensive mast cell (typical and atypical) infiltrates. Liver biopsy and abdominal lymphnode biopsy specimens and bone marrow smears also showed similar infiltration by mast cells. Special stains done for non-specific esterase and chloracetate esterase showed strong positivity for mast cells. The results of immunohistochemical and electron microscopic studies are also presented.
Asunto(s)
Sarcoma de Mastocitos/patología , Humanos , Masculino , Persona de Mediana EdadAsunto(s)
Dermatomicosis/epidemiología , Clima Tropical , Adolescente , Adulto , Niño , Preescolar , Dermatomicosis/etiología , Femenino , Humanos , India , Lactante , Recién Nacido , Masculino , Persona de Mediana EdadRESUMEN
A case of phaeohyphomycosis caused by Cladosporium bantianum is reported from India for the first time. It is also the first known case of infection involving the foot caused by this fungus. The cultural characteristics and animal pathogenicity of the isolate are described.