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1.
Ecotoxicol Environ Saf ; 114: 257-62, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24836933

RESUMEN

Fly ash (FA), a byproduct of coal combustion in thermal power plants, has been considered as a problematic solid waste and its safe disposal is a cause of concern. Several studies proposed that FA can be used as a soil additive; however its effect on microbial response, soil enzymatic activities and heavy metal accumulation in soil and grain of rice (cv. Naveen) to fly ash (FA) application was studied in a pot experiment during dry season 2011 in an Inceptisol. Fly ash was applied at a rate of zero per cent (FS), five per cent (FA5), ten per cent (FA10), twenty per cent (FA20), 40 per cent (FA40) and 100 per cent (FA100) on soil volume basis with nitrogen (N), phosphorus (P) and potassium (K) (40:20:20mg N:P:Kkg(-1) soil) with six replications. Heavy metals contents in soil and plant parts were analysed after harvest of crop. On the other hand, microbial population and soil enzymatic activities were analysed at panicle initiation stage (PI, 65 days after transplanting) of rice. There was no significant change in the concentration of zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), cadmium (Cd) and chromium (Cr) with application of fly ash up to FA10. However, at FA100 there was significant increase of all metals concentration in soil than other treatments. Microorganisms differed in their response to the rate of FA application. Population of both fungi and actinomycetes decreased with the application of fly ash, while aerobic heterotrophic bacterial population did not change significantly up to FA40. On the other hand, total microbial activity measured in terms of Fluorescein diacetate (FDA) assay, and denitrifiers showed an increased trend up to FA40. However, activities of both alkaline and acid phosphatase were decreased with the application of FA. Application of FA at lower levels (ten to twenty per cent on soil volume basis) in soil enhanced micronutrients content, microbial activities and crop yield.


Asunto(s)
Ceniza del Carbón/farmacología , Metales Pesados/análisis , Oryza/química , Microbiología del Suelo , Suelo/química , Actinobacteria/aislamiento & purificación , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Nitrógeno/metabolismo , Residuos Sólidos
2.
Nat Genet ; 23(1): 108-12, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471510

RESUMEN

G protein-coupled receptors (GPCRs) participate in the most common signal transduction system at the plasma membrane. The wide distribution of heterotrimeric G proteins in the internal membranes suggests that a similar signalling mechanism might also be used at intracellular locations. We provide here structural evidence that the protein product of the ocular albinism type 1 gene (OA1), a pigment cell-specific integral membrane glycoprotein, represents a novel member of the GPCR superfamily and demonstrate that it binds heterotrimeric G proteins. Moreover, we show that OA1 is not found at the plasma membrane, being instead targeted to specialized intracellular organelles, the melanosomes. Our data suggest that OA1 represents the first example of an exclusively intracellular GPCR and support the hypothesis that GPCR-mediated signal transduction systems also operate at the internal membranes in mammalian cells.


Asunto(s)
Albinismo Ocular/genética , Proteínas del Ojo/fisiología , Membranas Intracelulares/fisiología , Glicoproteínas de Membrana/fisiología , Transducción de Señal , Secuencia de Aminoácidos , Animales , Células COS , Proteínas del Ojo/genética , Proteínas de Unión al GTP/fisiología , Humanos , Lisosomas/metabolismo , Melanocitos/citología , Melanocitos/metabolismo , Glicoproteínas de Membrana/genética , Modelos Biológicos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Mutación Missense , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Transfección
3.
Hum Reprod ; 24(9): 2205-16, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19460863

RESUMEN

BACKGROUND: To our knowledge, there are no data on hormonal regulation of reticuloplasmins in primate endometrium. We report the presence and modulation of expression of three reticuloplasmins in endometrium of bonnet monkeys (Macaca radiata). METHODS: Receptive and non-receptive endometria obtained from vehicle-treated control and onapristone (antiprogestin)-treated animals, respectively, were compared for differentially expressed proteins by two-dimensional proteomics. Mass spectrometric analysis annotated two such proteins as calreticulin and protein disulfide-isomerase (PDI), known to be molecular chaperones in endoplasmic reticulum. We then investigated if endoplasmin, another reticuloplasmin is also differentially expressed. Expression of these reticuloplasmins was also investigated in the endometriuma during pregnancy in bonnet monkeys. Samples were analysed by immunohistochemistry and western blot (calreticulin in human endometrium), and calreticulin transcript levels in Ishikawa cell line were assessed by real time PCR. RESULTS: Immunohistochemical analysis of the functionalis region of non-receptive endometria in monkeys revealed higher expression of (i) calreticulin (P < 0.01) in glandular epithelium and (ii) PDI in stroma (P < 0.0001), but no change in endoplasmin in stroma or glands, compared with receptive endometria. Protein level of all three reticuloplasmins in the stromal region of endometrial functionalis was higher in pregnant than non-pregnant animals (P < 0.05). Human endometrial calreticulin protein was higher in the estrogen-dominant (proliferative) phase than progesterone-dominant (mid-secretory) phase of the cycle. Calreticulin mRNA in Ishikawa cells is up-regulated by estrogen (P < 0.05 versus control), with a trend towards down-regulation by progesterone. CONCLUSION: Our data suggest that endometrial reticuloplasmins are regulated by hormones and embryonic stimuli in a cell-type specific manner. These novel data open up new lines of investigation for elucidating the mechanisms by which hormones or embryonic stimuli influence the sub-cellular physiology of endometrium.


Asunto(s)
Calreticulina/genética , Endometrio/metabolismo , Adulto , Animales , Calreticulina/biosíntesis , Línea Celular Tumoral , Femenino , Expresión Génica/fisiología , Gonanos/farmacología , Humanos , Macaca radiata , Glicoproteínas de Membrana/biosíntesis , Proteína Disulfuro Isomerasas/biosíntesis
4.
J Cell Biol ; 150(4): 905-12, 2000 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-10953014

RESUMEN

Membrane receptors are internalized either constitutively or upon ligand engagement. Whereas there is evidence for differential regulation of the two processes, little is known about the molecular machinery involved. Previous studies have shown that an unidentified kinase substrate is required for endocytosis of the epidermal growth factor receptor (EGFR), the prototypical ligand-inducible receptor, but not of the transferrin receptor (TfR), the prototypical constitutively internalized receptor. Eps15, an endocytic protein that is tyrosine phosphorylated by EGFR, is a candidate for such a function. Here, we show that tyrosine phosphorylation of Eps15 is necessary for internalization of the EGFR, but not of the TfR. We mapped Tyr 850 as the major in vivo tyrosine phosphorylation site of Eps15. A phosphorylation-negative mutant of Eps15 acted as a dominant negative on the internalization of the EGFR, but not of the TfR. A phosphopeptide, corresponding to the phosphorylated sequence of Eps15, inhibited EGFR endocytosis, suggesting that phosphotyrosine in Eps15 serves as a docking site for a phosphotyrosine binding protein. Thus, tyrosine phosphorylation of Eps15 represents the first molecular determinant, other than those contained in the receptors themselves, which is involved in the differential regulation of constitutive vs. regulated endocytosis.


Asunto(s)
Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/metabolismo , Endocitosis/fisiología , Receptores ErbB/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Receptores de Transferrina/metabolismo , Tirosina , Proteínas Adaptadoras Transductoras de Señales , Sustitución de Aminoácidos , Animales , Células COS , Línea Celular , Membrana Celular/fisiología , Membrana Celular/ultraestructura , Núcleo Celular/fisiología , Núcleo Celular/ultraestructura , Péptidos y Proteínas de Señalización Intracelular , Ligandos , Ratones , Mutagénesis Sitio-Dirigida , Fosforilación , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transducción de Señal , Transfección
5.
J Cell Biol ; 151(6): 1345-52, 2000 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-11121447

RESUMEN

Numb is a protein that in Drosophila determines cell fate as a result of its asymmetric partitioning at mitosis. The function of Numb has been linked to its ability to bind and to biologically antagonize Notch, a membrane receptor that also specifies cell fate. The biochemical mechanisms underlying the action of Numb, however, are still largely unknown. The wide pattern of expression of Numb suggests a general function in cellular homeostasis that could be additional to, or part of, its action in fate determination. Such a function could be endocytosis, as suggested by the interaction of Numb with Eps15, a component of the endocytic machinery. Here, we demonstrate that Numb is an endocytic protein. We found that Numb localizes to endocytic organelles and is cotrafficked with internalizing receptors. Moreover, it associates with the appendage domain of alpha adaptin, a subunit of AP2, a major component of clathrin-coated pits. Finally, fragments of Numb act as dominant negatives on both constitutive and ligand-regulated receptor-mediated internalization, suggesting a general role for Numb in the endocytic process.


Asunto(s)
Endocitosis , Hormonas Juveniles/metabolismo , Complejo 2 de Proteína Adaptadora , Subunidades alfa de Complejo de Proteína Adaptadora , Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular , Proteínas de Unión al Calcio , Compartimento Celular , Proteínas de Drosophila , Endocitosis/genética , Técnica del Anticuerpo Fluorescente Indirecta , Sustancias de Crecimiento/farmacología , Proteínas de Insectos/metabolismo , Proteínas de la Membrana/metabolismo , Orgánulos/metabolismo , Fragmentos de Péptidos/metabolismo , Fosfoproteínas , Unión Proteica
6.
J Cell Biol ; 121(6): 1221-32, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8509445

RESUMEN

Expression of chimeras, composed of portions of two different glucose transporter isoforms (GLUT-1 and GLUT-4), in CHO cells had indicated that the cytoplasmic NH2 terminus of GLUT-4 contains important targeting information that mediates intracellular sequestration of this isoform (Piper, R. C., C. Tai, J. W. Slot, C. S. Hahn, C. M. Rice, H. Huang, D. E. James. 1992. J. Cell Biol. 117:729-743). In the present studies, the amino acid constituents of the GLUT-4 NH2-terminal targeting domain have been identified. GLUT-4 constructs containing NH2-terminal deletions or alanine substitutions within the NH2 terminus were expressed in CHO cells using a Sindbis virus expression system. Deletion of eight amino acids from the GLUT-4 NH2 terminus or substituting alanine for phenylalanine at position 5 in GLUT-4 resulted in a marked accumulation of the transporter at the plasma membrane. Mutations at other amino acids surrounding Phe5 also caused increased cell surface expression of GLUT-4 but not to the same extent as the Phe5 mutation. GLUT-4 was also localized to clathrin lattices and this colocalization was abolished when either the first 13 amino acids were deleted or when Phe5 was changed to alanine. To ascertain whether the targeting information within the GLUT-4 NH2-terminal targeting domain could function independently of the glucose transporter structure this domain was inserted into the cytoplasmic tail of the H1 subunit of the asialoglycoprotein receptor. H1 with the GLUT-4 NH2 terminus was predominantly localized to an intracellular compartment similar to GLUT-4 and was sequestered more from the cell surface than was the wild-type H1 protein. It is concluded that the NH2 terminus of GLUT-4 contains a phenylalanine-based targeting motif that mediates intracellular sequestration at least in part by facilitating interaction of the transporter with endocytic machinery located at the cell surface.


Asunto(s)
Proteínas de Transporte de Monosacáridos/química , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas Musculares , Secuencia de Aminoácidos , Animales , Transporte Biológico , Células CHO , Clatrina , Cricetinae , Desoxiglucosa/metabolismo , Transportador de Glucosa de Tipo 4 , Datos de Secuencia Molecular , Mutación , Fenilalanina , Señales de Clasificación de Proteína/fisiología , Eliminación de Secuencia , Relación Estructura-Actividad , Fracciones Subcelulares/metabolismo
7.
Hum Reprod ; 23(2): 379-86, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18033938

RESUMEN

BACKGROUND: This study is an attempt to construct a repository of polypeptide species in human uterine fluid during the mid-secretory phase of menstrual cycle. This information is essential to generate alternative and less invasive tools for the assessment of uterine functions. METHODS: Two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and mass spectrometric analysis were used to resolve and identify the major components of human uterine fluid. RESULTS: Uterine fluid collected during the mid-secretory phase (n = 6) demonstrated ca. 590 polypeptide spots in the linear range of pH 4-7 after 2D PAGE. Mass spectrometric analysis revealed the presence of heavy and light chains of immunoglobulins, alpha-1 anti-trypsin precursor, anti-chymotrypsin precursor, haptoglobin, apolipoprotein A4, apolipoprotein A1 fragment, beta-actin fragment, heat shock protein 27, hemopexin precursor and transferrin precursor. 2D protein profile of fluid collected during the proliferative phase (n = 5) revealed ca. 433 polypeptide spots, of which 279 could be paired with mid-secretory phase protein spots on the basis of their coordinates (isoelectric point and molecular weight) in 2D gels. Apolipoprotein A4, apolipoprotein A1 fragment and alpha-1 anti-trypsin precursor were 2-3-fold more abundant in uterine fluid collected during the mid-secretory phase as compared with that in the proliferative phase. Further, 86 uterine fluid polypeptides were conserved across species, being detected in human, rat and bonnet monkeys. CONCLUSIONS: The molecular repertoire of the mid-secretory phase human uterine fluid, when compared with that of the proliferative phase uterine fluid, is broadened due to differential expression of proteins. Further, some of the mid-secretory phase proteins were conserved across species.


Asunto(s)
Líquidos Corporales/química , Fase Luteínica/metabolismo , Péptidos/análisis , Útero/metabolismo , Adulto , Animales , Electroforesis en Gel Bidimensional , Femenino , Fase Folicular/metabolismo , Humanos , Macaca radiata , Espectrometría de Masas , Ratas , Ratas Endogámicas
8.
Biochim Biophys Acta ; 1175(1): 73-80, 1992 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1482698

RESUMEN

To investigate whether the synthetic progesterone antagonist ZK-98.299 binds to progesterone receptor or also has distinct binding sites, the binding characteristics of ZK-98.299 were compared with those of progesterone in the human myometrial cytosol. [3H]ZK-98.299 and [3H]progesterone showed specific binding in the myometrial cytosol and the binding of each radiolabelled ligand could be displaced with the respective ligand in a dose-response manner. However, while the binding of [3H]progesterone could be completely blocked with progesterone or ZK 98.299, the binding of [3H]ZK-98.299 could not be displaced more than 50%. The non-specific binding of [3H]ZK-98.299 was very high as compared to that of [3H]progesterone. Using [3H]progesterone, the relative binding affinity (RBA) of progesterone was more than that of ZK 98.299, whereas using [3H]ZK-98.299 the RBA of ZK 98.299 exceeded that of progesterone. Treatment of myometrial cytosol with increasing concentrations of -SH-modifying agents (iodoacetamide (IA) 0-10 mM or N-ethylmaleimide (NEM) 0-1000 nM) decreased the binding of progesterone by over 80%, whereas similar treatment did not have appreciable effect on the binding of [3H]ZK-98.299. Although both preformed ligand-receptor complexes were relatively stable in the presence of IA and NEM, the [3H]progesterone-receptor complex was more sensitive as compared to the [3H]ZK-98.299-receptor complex. The addition of 20 mM molybdate in the cytosol had a protective effect against the -SH-modifying agents. [3H]ZK-98.299 and [3H]progesterone-receptor complexes also showed differential stability when incubated at elevated temperatures (25 degrees C and 37 degrees C), [3H]ZK-98.299-binding sites being more thermolabile as compared to [3H]progesterone binding sites. Prior occupation of the receptor by the two ligands gave the complexes the ability to resist an elevated temperature of 25 degrees C. Moreover, molybdate stabilized both the liganded and unoccupied receptors at 25 degrees C. When the ligand-receptor complexes were applied onto a prefocused polyacrylamide gel, the progesterone and ZK-98.299-receptor complexes were resolved and focused at pH 7.2 and 8.4, respectively. The results of this study suggest that although progesterone and ZK-98.299 are mutually competitive for binding to progesterone receptor, ZK-98.299 also has distinct binding sites.


Asunto(s)
Gonanos/metabolismo , Miometrio/metabolismo , Progesterona/antagonistas & inhibidores , Sitios de Unión , Unión Competitiva , Citosol/metabolismo , Etilmaleimida/farmacología , Femenino , Gonanos/farmacología , Humanos , Yodoacetamida/farmacología , Receptores de Progesterona/metabolismo , Temperatura
9.
Biochim Biophys Acta ; 1011(2-3): 176-82, 1989 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-2713402

RESUMEN

The binding of ZK 98.299, a synthetic progesterone antagonist, with human endometrium and myometrium cytosol was studied and compared with that of progesterone. Progesterone showed specific saturable binding to its receptors in both endometrium and myometrium. ZK 98.299 and progesterone were mutually competitive for binding to progesterone receptors; however, the relative binding affinity of ZK 98.299 was 16% that of progesterone. ZK 98.299 exchanged the progesterone-labelled receptor sites. [3H]ZK 98.299 showed specific binding which was linearly related to the cytosol protein concentration. The binding was not saturable at 15 nM of ligand. The binding capacity and binding affinity of ZK 98.299 receptor was less than that of progesterone. Progesterone also partially displaced the binding of [3H]ZK 98.299. This study suggest that ZK 98.299 and progesterone both bind to the same protein. However, whether ZK 98.299 binds to progesterone receptors alone or even to other functionally related sites is not known. It appears that ZK 98.299 when present in higher concentration than progesterone would be an effective receptor ligand.


Asunto(s)
Endometrio/metabolismo , Gonanos/metabolismo , Miometrio/metabolismo , Progesterona/antagonistas & inhibidores , Progesterona/metabolismo , Adulto , Unión Competitiva , Citosol/metabolismo , Femenino , Humanos , Técnicas In Vitro , Cinética , Receptores de Progesterona/metabolismo
10.
J Mol Endocrinol ; 35(2): 357-72, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16216915

RESUMEN

Acquisition of functional receptivity by the endometrium is assumed to be effected by progesterone-dependent expression and repression of several genes during the implantation window in a menstrual cycle. In the present study, we employed differential display (DD) reverse transcription-polymerase chain reaction (RT-PCR) to identify progesterone-dependent gene/gene fragments that are differentially expressed during the peri-implantation phase in receptive and nonreceptive endometria, obtained from fertile and infertile bonnet monkeys respectively. Receptive endometria were obtained from regularly cycling (n=5) fertile female bonnet monkeys. Endometrial nonreceptivity was induced by treating bonnet monkeys with either 2.5 mg (n=5) or 5.0 mg (n=5) onapristone (ZK 98.299), an antiprogestin, on every third day for one cycle. Ovulation, levels of circulatory hormones (estradiol and progesterone) and menstrual cycle length did not change in treated animals; however, endometrial growth was retarded. DD2, one of the differentially expressed cDNA fragments, showed higher representation in nonreceptive endometria than in receptive endometria. The DD2 sequence was found to be homologous to the sequence of the carboxyl terminal region of Rab coupling protein (RCP), a recently discovered protein involved in intracellular vesicular trafficking. To confirm the identity of DD2 as RCP, RT-PCR studies were carried out with a forward primer deduced from the RCP sequence and a reverse primer from the DD2 sequence. The product (DDRCP) obtained, when sequenced, revealed 95% homology with the nucleotide number 1196-1757 of human RCP cDNA. Furthermore, the pattern of DDRCP expression at transcript level was found to be similar to that shown by DD2; that is, it was higher in nonreceptive endometrium. Northern analysis using labeled DD2 or DDRCP cDNA fragments identified two transcripts of 6.0 and 4.0 kb in human endometrium. In situ hybridization studies using digoxigenin-labeled DD2 revealed significantly higher (P < 0.05) localization of endometrial RCP transcripts in the proliferative phase than in the peri-implantation phase in control animals. The localization was also significantly (P < 0.01) higher in peri-implantation-phase endometria from antiprogestin-treated animals than in control animals. These antiprogestin-treated animals, however, did not demonstrate any concomitant increase in the levels of immunoreactive endometrial Rab4 and Rab11 during the peri-implantation phase. A similar pattern of cycle-dependent RCP expression was observed in human endometrial biopsies. Furthermore, significantly higher (P < 0.05) levels of RCP transcripts were detected during the peri-implantation phase in women with unexplained infertility (n=3) than in fertile women (n=3). This is the first report indicating the endometrial expression of RCP and its hormonal regulation.


Asunto(s)
Proteínas Portadoras/metabolismo , Endometrio/metabolismo , Macaca radiata , Proteínas de la Membrana/metabolismo , Progesterona/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Endometrio/citología , Femenino , Perfilación de la Expresión Génica , Humanos , Hibridación in Situ , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Alineación de Secuencia , Técnicas de Cultivo de Tejidos , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo , Proteínas de Unión al GTP rab4/genética , Proteínas de Unión al GTP rab4/metabolismo
11.
Endocrinology ; 140(5): 2297-306, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10218983

RESUMEN

The type 4 cAMP-specific phosphodiesterases (PDE4) are a family of closely related enzymes with similar catalytic domains and divergent amino- and carboxyl-terminus domains. Multiple PDE proteins with heterogeneous amino termini are derived from each gene. To understand the significance of this heterogeneity, the expression and localization of variants derived from PDE4A and PDE4D genes was investigated during spermatogenesis in the rat. RNase protection analysis with mRNA for testes at different ages of development showed that two transcripts (PDE4D1 and PDE4D2) are expressed at day 10 and 15 of age and become undetectable thereafter. An additional PDE4D transcript appears at day 30 and increased during testid maturation. This latter transcript codes for a long variant of the PDE4D gene and is expressed in germ cells as demonstrated by RNase protection with RNA from isolated pachytene spermatocytes and round spermatids. The presence of a corresponding PDE4D protein with a molecular mass of 98 kDa was established by immunoprecipitation and Western blot analysis with antibodies specific for PDE4D and by immunoaffinity chromatography purification of the 98 kDa variant from isolated germ cells. PDE4A transcripts were also expressed in pachytene spermatocytes and round spermatids. Two polypeptides encoded by these PDE4A transcripts were expressed in pachytene spermatocytes, reached a maximum in round spermatids, and declined thereafter. Immunofluorescence analysis demonstrated a localization of the PDE4D protein in the manchette and in a periacrosomal region of the developing spermatid, a localization confirmed by immunogold electron microscopy. Conversely, the PDE4A was mostly soluble in the cytoplasm of round spermatids. These data demonstrate that PDE4D and PDE4A variants are expressed at different stages and localized in distinct subcellular structures of developing spermatids. Different properties of the mRNAs derived from the two genes and localization signals are responsible for the temporal and spatial expression of the different PDE4 isoenzymes.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/genética , Expresión Génica , Isoenzimas/genética , Espermatogénesis , Testículo/enzimología , Animales , Técnica del Anticuerpo Fluorescente , Hormona Folículo Estimulante/farmacología , Variación Genética , Masculino , Microscopía Inmunoelectrónica , Empalme del ARN , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/enzimología , Células de Sertoli/efectos de los fármacos , Células de Sertoli/enzimología , Espermatozoides/enzimología , Testículo/crecimiento & desarrollo
12.
Mol Biochem Parasitol ; 92(1): 147-62, 1998 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9574918

RESUMEN

The apicomplexan parasite Cryptosporidium parvum invades and multiplies primarily in the brush border cells of the intestinal mucosa causing in AIDS patients a severe diarrhoea that represents a significant contributing factor leading to death. Morphological analysis indicates that the invasion machinery of C. parvum is similar to the apical complex of other parasites of the phylum Apicomplexa. We provide here evidence indicating that C. parvum also shares with these parasites a molecule crucial for the invasion of host cells. We have cloned a 3894 bp-long C. parvum cDNA encoding a protein characterised by sequence and structural similarities with members of the thrombospondin (TSP) family previously described in apicomplexan parasites of the genera Toxoplasma, Eimeria and Plasmodium. This novel C. partum molecule, the TSP-related adhesive protein of Cryptosporidium-1 (TRAP-C1), is encoded by a single copy gene containing no introns. TRAP-C1 is localised in the apical end of C. parvum sporozoites and is structurally related to the micronemal proteins MIC2 of Toxoplasma and Etp100 of Eimeria, which are involved in host-cell attachment and/or invasion. The identification of TRAP-C1 sheds new light on the molecules possibly involved in the invasion process of intestinal cells by C. parvum. We have also analysed the sequence variation of TRAP-C1 among C. parvum isolates and in the closely related species C. wrairi.


Asunto(s)
Cryptosporidium parvum/genética , Genes Protozoarios , Familia de Multigenes , Proteínas Protozoarias/genética , Trombospondinas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Compartimento Celular , Cryptosporidium/genética , Biblioteca de Genes , Datos de Secuencia Molecular , Polimorfismo Genético , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Especificidad de la Especie
13.
Brain Res ; 200(2): 377-87, 1980 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-7417822

RESUMEN

Testosterone (T), cortisol (C), prolactin (PRL) and bioactive luteinizing hormone (bLH) were found to be normal constituents of the cerebrospinal fluid (CSF) of all the 15 adult male rhesus monkeys studied. The CSF levels of the hormones showed a good correlation with their serum levels. The geometric mean values of circulating levels of T, PRL, bLH in all the animals studied were significantly lower in the samples of the two body fluids collected between 09.00 and 11.00 h as compared with those collected between 21.00 and 23.00 h. C levels were higher during the day as compared with the night samples. This marked difference between the day and night levels of the circulating hormones was not observed in a few individuals which suggests that the diurnal changes in circulating levels of these hormones may not occur as a rule in all rhesus monkeys. The serum:CSF ratios for C, PRL and bLH did not vary significantly between the day and night samples of the body fluids as they did for T. This suggests that T is poorly transferred from the blood to the CSF as compared with the other 3 hormones studied. The possible pathways by which the hormones are transferred into the CSF and the functional significance of their presence in the CSF are discussed.


Asunto(s)
Ritmo Circadiano , Hidrocortisona/líquido cefalorraquídeo , Hormona Luteinizante/líquido cefalorraquídeo , Prolactina/líquido cefalorraquídeo , Testosterona/líquido cefalorraquídeo , Animales , Hidrocortisona/sangre , Hormona Luteinizante/sangre , Macaca mulatta , Masculino , Prolactina/sangre , Testosterona/sangre
14.
Steroids ; 65(10-11): 783-94, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11108889

RESUMEN

Modulation of endometrial receptivity is a promising approach for fertility regulation since it allows a contraceptive to act specifically at the endometrium. This was corroborated by our previous observations that treatment with low doses of a pure progesterone antagonist (PA, antiprogestin), onapristone (ZK 98299), in bonnet monkeys inhibited fertility by selectively retarding endometrial development, without affecting the hypophyseal-hypothalamic function. In the present study, further investigations, undertaken to analyze the molecular repertoire of a nonreceptive primate endometrium, determined expression of: steroid hormone receptors, i.e. progesterone receptor (PR) and estrogen receptor (ER); cytokines, i.e. leukemia inhibitory factor (LIF): transforming growth factor beta (TGFbeta) and its receptor (TGFbetaR); and cell adhesion molecules, i.e. integrins (alpha(v)beta(3), alpha(1)beta(1)). These studies were conducted during the different phases of the normal menstrual cycle and following treatment with different doses of onapristone (2.5 mg, 5 mg, or 10 mg every third day for one cycle) in bonnet monkeys. The molecules were analysed collectively to explore the possibility of a correlation between expression of these markers and endometrial receptivity and to investigate whether there exists a regulatory link between expression of these molecules under in vivo conditions. Three types of expression patterns of endometrial factors were observed during the peri-implantation period following onapristone treatment: 1) LIF, alpha(v)beta(3), and alpha(1)beta(1) showed significant (P < 0.02) down regulation in glandular epithelium of endometria in animals treated with all three doses of onapristone as compared to the control group. This was indicative of their critical role in the progesterone-driven cascade leading to implantation. 2) PR, TGFbeta, and TGFbetaR remained unaffected in the endometria from 2.5 mg treated animals and showed down regulation in animals treated with 5 and 10 mg onapristone as compared to the control group, thereby suggesting that the expression of these markers may not truely reflect endometrial receptivity per se. However, their facilitatory role in preparing the endometrium for implantation can not be ruled out since continued perturbation in the expression of these molecules may affect endometrial growth, remodelling, and differentiation, which in turn may render the endometrium nonreceptive; 3) ER remained unaltered in endometria of animals rendered infertile with 2.5, 5, and 10 mg onapristone. This observation indirectly suggests that onapristone-induced endometrial changes are mediated via some specific mechanisms. The present study clearly demonstrates that endometrial non-receptivity induced at low doses of onapristone is associated with changes in the expression pattern of specific molecular markers. However, no direct correlation was observed between in vivo expression of TGFbeta, LIF, and integrins, thereby lending support to the concept that there exists redundancy or multiple pathways which regulate implantation events.


Asunto(s)
Endometrio/efectos de los fármacos , Gonanos/farmacología , Interleucina-6 , Animales , Moléculas de Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Relación Dosis-Respuesta a Droga , Endometrio/química , Endometrio/citología , Femenino , Gonanos/administración & dosificación , Inhibidores de Crecimiento/genética , Inhibidores de Crecimiento/metabolismo , Inmunohistoquímica , Factor Inhibidor de Leucemia , Linfocinas/efectos de los fármacos , Linfocinas/genética , Linfocinas/metabolismo , Macaca radiata , Ciclo Menstrual , ARN Mensajero/metabolismo , Receptores de Estrógenos/efectos de los fármacos , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/efectos de los fármacos , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/efectos de los fármacos , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factores de Crecimiento Transformadores/efectos de los fármacos , Factores de Crecimiento Transformadores/genética , Factores de Crecimiento Transformadores/metabolismo
15.
Contraception ; 35(4): 409-21, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3621940

RESUMEN

The antiprogestin ZK 98.299 (11 beta-(4-dimethylaminophenyl)-17 alpha-hydroxy-17 beta-(3-hydroxypropyl)-13 alpha-methyl-4,9-gonadien-3-one) was administered s.c. (30mg/day) to two groups of cycling bonnet monkeys. In Group I (n = 6), it was injected from day 16 to 18 and in Group II (n = 9) from day 21 to 23 of the cycle. Each animal served as its own control and in the pretreatment cycle the vehicle (benzyl benzoate: castor oil, 1:4) was administered. During the treatment cycle of these animals the peak in estradiol levels was observed between days 8 to 11 of the menstrual cycle. In Group I animals, administration of ZK 98.299 induced vaginal bleeding in three of the six animals within two days of its first injection. In the remaining three animals the menstrual cycle length was prolonged. However, in all the six animals a premature drop in serum progesterone levels was observed. On the other hand, in Group II in seven animals with ovulatory treatment cycles, administration of ZK 98.299 induced vaginal bleeding within four days of the first dose and significantly shortened the cycle length. A significant decline in progesterone levels was observed in these animals also. However, in two animals in each group, ZK 98.299 induced vaginal bleeding while the serum progesterone levels were still high. Post-treatment cycles were ovulatory but the cycle length was marginally increased in some animals. In two animals of Group II, in which the treatment cycle turned out to be anovulatory, ZK 98.299 did not induce bleeding and had no effect on serum progesterone levels. This study shows that when administered during the luteal phase ZK 98.299 induces vaginal bleeding and premature luteal regression in bonnet monkeys. However, induction of vaginal bleeding may not be associated with drop in progesterone levels. ZK 98.299, therefore, appears to have potential for fertility control which warrants clinical evaluation.


Asunto(s)
Gonanos/farmacología , Ciclo Menstrual/efectos de los fármacos , Progesterona/antagonistas & inhibidores , Animales , Cuerpo Lúteo/efectos de los fármacos , Estradiol/sangre , Estrenos/farmacología , Femenino , Macaca radiata , Mifepristona , Progesterona/sangre
16.
Contraception ; 41(2): 197-205, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2311405

RESUMEN

The antiprogestin ZK 98.299 (onapristone) was injected subcutaneously (25 mg/day) for 4 consecutive days during early pregnancy to 8 bonnet monkeys. Retrospective analysis of the data showed that the treatment was initiated between 20 to 30 days after the mid-cycle peak in estradiol levels. In 7 animals, vaginal bleeding was induced within 3.6 +/- 2.7 days (mean +/- S.D.) after the initiation of treatment. However, pregnancy was terminated completely only in 5 animals. In these 5 animals, menstruation was induced 1 to 4 days after the initiation of treatment. Serum progesterone levels also decreased; however, a significant decrease (p less than 0.02) in mean levels was not observed until 5 days after the initiation of treatment. In the other 3 animals, in spite of some drop in serum progesterone levels after the treatment and slight vaginal bleeding in 2 animals, the pregnancy continued. Two animals delivered stillborn foetuses at term. The foetuses weighed 92 and 105 g, which is markedly lower than the normal foetal weight (345 +/- 48 g, n = 6) at birth. The gross appearance of the foetuses was suggestive of recent intrauterine foetal death. In the third animal hysterotomy was performed on day 65; foetus weighed 5 g. Haematoma and blood clots were seen in the placental tissue. This limited data on 8 animals demonstrates that ZK 98.299, at the dose regimen employed, completely terminates early pregnancy in 62% of animals. In the cases in which treatment failed, the pregnancy did not continue unaffected. The endocrine function of the placenta was affected and the foetal growth was retarded.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Gonanos/farmacología , Progesterona/antagonistas & inhibidores , Aborto Inducido , Animales , Femenino , Inyecciones Subcutáneas , Macaca radiata , Placenta/efectos de los fármacos , Embarazo , Resultado del Embarazo , Factores de Tiempo
17.
Contraception ; 39(2): 227-43, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2706991

RESUMEN

ZK 98.299 is a potent progesterone antagonist. Its effects on folliculogenesis, bioactive LH, ovulation and menstrual cycle (m.c.) length were studied in adult bonnet monkeys. ZK 98.299 (20 mg/day) was administered s.c., once daily on days 5 to 15 of m.c., to ten animals. The pretreatment m.c. was of 26.5 days (25 to 28 days, mean with 95% confidence limits) and on treatment it was significantly (p less than 0.001) prolonged to 46.9 days (39 to 54 days). The anticipated midcycle rise in estradiol and bioactive LH levels was completely blocked in six and attenuated in three animals during the treatment period. However, the levels did not drop below the early follicular phase levels. In one animal (#90), though the cycle length was prolonged by 5 days the midcycle rise in estradiol and bioactive LH levels was observed during the treatment period and this animal had normal luteal function. Seven animals had delayed ovulation whereas, two had anovulatory treatment cycles. The rise in estradiol and bioactive LH levels, prior to ovulation in the treatment cycles, was compatible with the midcycle rise observed in the pretreatment cycles. Serum progesterone levels during the luteal phase of the treatment cycles were normal in six animals whereas, in two they were indicative of luteal insufficiency. In two animals, the treatment cycles were anovulatory. ZK 98.299 had no effect on the duration of menses. The post-treatment cycles were of normal duration. This study suggests that the administration of ZK 98.299 during the follicular phase blocks estradiol and bioactive LH release and terminates the follicular phase in most of the animals. The follicular phase is reinitiated after the treatment is stopped.


Asunto(s)
Fase Folicular/efectos de los fármacos , Gonanos/farmacología , Animales , Estradiol/sangre , Femenino , Hormona Luteinizante/sangre , Macaca radiata , Ciclo Menstrual/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Factores de Tiempo
18.
Contraception ; 49(6): 593-9, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8070264

RESUMEN

Immunocytochemical localization of inhibin was carried out in paraffin embedded tissue sections of the control and antiprogestin (ZK 98.299)-treated bonnet monkey endometrium using polyclonal antibodies generated against human seminal plasma inhibin (10.5 kDa). The study shows that administration of low doses (5 mg/week) of antiprogestin results in an increase in the expression of inhibin by the endometrium. Treatment with higher doses (20 mg/week) caused a decrease in the expression. Since treatment with higher doses also caused atropic changes in the endometrium, the decrease in inhibin could be the result of morphological damage to the endometrium rather than the effects of antiprogestin on the expression of inhibin. The potential involvement of endometrial inhibin in the process of nidation is speculated.


Asunto(s)
Endometrio/metabolismo , Gonanos/farmacología , Inhibinas/metabolismo , Progesterona/antagonistas & inhibidores , Animales , Endometrio/efectos de los fármacos , Endometrio/ultraestructura , Epitelio/metabolismo , Femenino , Inmunohistoquímica , Cinética , Macaca radiata , Peso Molecular
19.
Contraception ; 48(1): 57-70, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8403906

RESUMEN

The effects of an antiprogestin ZK 98.299 (onapristone) on serum levels of estradiol and progesterone, and on the endometrial morphology were studied in adult bonnet monkeys. Twelve animals having menstrual cycles of normal duration (24 to 30 days) were randomly distributed into 4 equal groups. The animals in Group 1 were treated (s.c.) with the vehicle (benzyl benzoate: castor oil, 1:10), and in Groups 2, 3 and 4 with 5 mg, 10 mg, or 20 mg ZK 98.299 once-a-week, respectively. Treatment was initiated on day 1 of the menstrual cycle and each animal in Groups 1, 2 and 3 was treated for two consecutive cycles. Since the treatment cycle length of animals in Group 4 was considerably prolonged, they were treated for one menstrual cycle only. Endometrial biopsy was taken around day 20 of the second treatment cycle of first three groups and around day 50 of the 4th group of animals. Treatment with vehicle or 5 mg ZK 98.299 had no significant effect on the menstrual cycle length. Treatment with 10 mg dose had no effect in two animals and prolonged the cycle length in one, whereas, further increase in the dose to 20 mg prolonged the cycle length in all the animals. The duration of menses was generally reduced. Treatment with vehicle or different doses of ZK 98.299 had no effect on ovulation. In animals treated with 5 or 10 mg dose, the pattern of mid cycle rise in serum estradiol levels and progesterone levels during the luteal phase of both treatment cycles were comparable to those of vehicle-treated animals and were suggestive of normal ovulatory cycles. On the other hand, in animals treated with the higher dose (20 mg/week), progesterone levels during the luteal phase were significantly reduced and were indicative of luteal insufficiency. The hormonal data during the treatment period of this group of animals was suggestive of two distinct ovarian cycles indicating that the menstrual bleeding during the treatment period was probably very scanty. Treatment with ZK 98.299 impaired the endometrial development in a dose-dependent manner. In vehicle-treated animals, the endometrium had large and tortous glands with secretions. Treatment with ZK 98.299 caused atrophic changes in the glands as well as in the stroma. The height of the epithelial cells was markedly decreased and they became small and inactive. This study, therefore, suggests that treatment with low doses of antiprogestin ZK 98.299 at weekly intervals does not block folliculogenesis or ovulation, but has an inhibitory effect on the endometrium.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Endometrio/efectos de los fármacos , Hormonas Esteroides Gonadales/sangre , Gonanos/farmacología , Ovulación/efectos de los fármacos , Progesterona/antagonistas & inhibidores , Animales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Endometrio/patología , Femenino , Fase Folicular/efectos de los fármacos , Macaca radiata , Ciclo Menstrual/efectos de los fármacos , Factores de Tiempo
20.
Contraception ; 35(4): 381-8, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3621938

RESUMEN

Pharmacokinetic parameters of norethisterone (NET) were studied in eight adult male bonnet monkeys following the administration of a single dose of 300 ug. The animals were crossed over between the following three routes of administration: oral ingestion, nasal and sublingual spraying. The results indicate that NET was readily absorbed by all three routes but the Cmax and AUC of NET were significantly greater by the sublingual route. No significant difference in the t 1/2 alpha or t 1/2 beta was observed between the three routes. These findings suggest that the sublingual route offers the possibility of reducing the effective dose of NET, which is widely used for contraceptive purposes.


Asunto(s)
Noretindrona/sangre , Administración Intranasal , Administración Oral , Animales , Cinética , Macaca radiata , Masculino , Noretindrona/administración & dosificación , Lengua
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