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1.
Insect Biochem Mol Biol ; 148: 103819, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35963292

RESUMEN

A prostate trypsin-like serine endopeptidase called initiatorin (BmIni) is an essential factor in triggering the sperm maturation response of the silkworm, Bombyx mori. BmIni has been predicted to specifically cleave the carboxyl side of two consecutive arginine residues present in certain seminal plasma and sperm proteins, but the actual substrates are still unknown. In an attempt to elucidate the molecular mechanism underlying the sperm maturation signaling pathway, in this study, we examined whether BmIni activates the seminal carboxypeptidase B (BmCPB) protein through specific degradation. First, we confirmed in vitro that the inactive BmCPB present in unmated male vesicula (v.) seminalis is activated by treatment with BmIni or trypsin. Molecular cloning of the gene encoding the seminal BmCPB protein has shown that BmCPB is produced as a secreted proenzyme and may be activated after a trypsin-like protease cleaves the boundary between the prodomain and the enzyme site. In support of these findings, both trypsin and BmIni significantly activated recombinant Pro-BmCPB, which was successfully expressed and purified as a proenzyme in Escherichia coli; moreover, two specific cleavage forms appeared in the activation by BmIni that did not appear in that by trypsin. Therefore, a recombinant protein with a mutated diarginine motif (Arg109-Arg110), which is presumed to be a pre-cleavage site of BmCPB based on its high homology with bovine CPB, was prepared and treated with BmIni. As a result, the two specific degraded peptides were no longer observed, and simultaneously the activation was suppressed. Taken together, these findings lead to the conclusion that zymogen BmCPB, which is synthesized and secreted in male reproductive organs, is activated by sequence-dependent proteolysis by BmIni during ejaculation and in the female reproductive organs, providing a clue to the mechanism underlying seminal plasma and/or sperm protein degradation by BmIni in the sperm maturation cascade of B. mori.


Asunto(s)
Bombyx , Animales , Bombyx/metabolismo , Carboxipeptidasa B/metabolismo , Bovinos , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Escherichia coli , Femenino , Masculino , Próstata/metabolismo , Proteolisis , Semen , Serina Endopeptidasas , Espermatozoides/metabolismo , Tripsina/metabolismo
2.
Ann Nucl Med ; 29(10): 890-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26307758

RESUMEN

OBJECTIVE: The purpose of this study is to evaluate whether prone myocardial perfusion single-photon emission computed tomography (MPS) with thallium-201 acquired through a variable-focus collimator (IQ-SPECT) can correct for soft-tissue attenuation. METHODS: Thirty-nine patients underwent thallium-201 stress MPS with IQ-SPECT. Delayed images acquired with the patients in the prone position were compared with delayed images obtained with the patients in the supine position with computed tomography-derived attenuation correction (CTAC) (S-CTAC images) or without CTAC (S-NCTAC images). Quantitative tracer uptake (QTU) and semi-quantitative defect scores were determined for the 17 standard myocardial segments. Segments were categorized into anterior-anteroseptal, lateral, inferior, and apex, and areas with defect decision were determined by using the defect scores. RESULTS: Image quality in the prone images was similar to that of S-NCTAC and S-CTAC images. In male patients, QTU in prone images was equivalent to that in S-CTAC images in the anterior-anteroseptal area, but was significantly lower than that in S-CTAC images in the inferior area. In female patients, QTU in prone images was similar to that in S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas. In male and in female patients, QTU in the apex was significantly greater in the prone images than that in the S-CTAC images. In the combined male and female patient group, the defect decision for prone images was similar to that for S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas. Apical defects were observed more frequently in S-CTAC images than in prone or S-NCTAC images. CONCLUSIONS: Fewer artificial defects were observed in the apex of images acquired by prone imaging than by S-CTAC imaging. Prone images improved attenuation and had similar defect decision as S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Imagen de Perfusión Miocárdica/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Transporte Biológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Posición Prona , Posición Supina , Radioisótopos de Talio/metabolismo
3.
J Genet Couns ; 24(6): 922-30, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25787091

RESUMEN

Undergoing chromosome analysis and receiving the results may have various psychosocial effects. To identify the impact on balanced translocation carriers identified through affected offspring, we conducted semi-structured interviews with eleven parents at Saitama Children's Medical Center. The results of the interviews were analyzed qualitatively by the KJ (Kawakita Jiro) method. Categories and subcategories of the various thoughts, emotions and responses experienced by balanced chromosomal translocation carriers were extracted. Participants' reactions were mixed, and appeared to be interrelated in some cases. Parents' reactions were sometimes ambivalent with regard to effects on reproductive issues and disclosure of test results. We recommend genetic counseling before and after carrier testing to help parents cope with the mixed and complex thoughts and feelings that arise upon being identified as a carrier.


Asunto(s)
Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/psicología , Padres/psicología , Translocación Genética , Adaptación Psicológica , Adulto , Niño , Preescolar , Femenino , Asesoramiento Genético/métodos , Humanos , Lactante , Japón , Masculino , Responsabilidad Parental/psicología
4.
Am J Physiol Cell Physiol ; 297(5): C1263-74, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19710365

RESUMEN

In vascular endothelial cells, specialized microdomains of plasma membrane termed caveolae modulate various receptor signal transduction pathways regulated by caveolin-1, a resident protein of caveolae. We examined whether transforming growth factor-beta1 (TGF-beta1), a multifunctional cytokine, alters expression levels of caveolin-1 and influences heterologous receptor signaling. Treatment of cultured bovine aortic endothelial cells (BAEC) with TGF-beta1 induces marked decreases in caveolin-1 expression in a time- and dose-dependent fashion at both levels of protein and mRNA. A pharmacological inhibitor of activin receptor-like kinase 5 (ALK-5) counteracts caveolin-1 downregulation by TGF-beta1, indicating the involvement of ALK-5 receptor subtype for TGF-beta1. Sphingosine 1-phosphate (S1P) is a serum-borne angiogenic lipid growth factor that exerts a wide variety of biological actions. S1P modulates G protein-coupled S1P receptors, activating downstream molecules kinases AMP-activated protein kinase (AMPK), and Akt as well as a small G protein Rac1, ultimately to promote migration. Because S1P receptor signaling is associated with caveolae/caveolin-1, we examined whether pretreatment with TGF-beta1 enhances effects of S1P on BAEC. Whereas S1P alone evokes robust BAEC responses to S1P, pretreatment with TGF-beta1 leads to even higher magnitudes of S1P-elicited signaling responses and cell migration. Conversely, genetic knockdown of caveolin-1 using small interfering RNA mimics TGF-beta1-induced promotion of BAEC responses to S1P. Collectively, these data demonstrate that TGF-beta1 downregulates caveolin-1 of cultured endothelial cells, involving ALK-5 receptor subtype. Because downregulation of caveolin-1 by TGF-beta1 promotes subsequent heterologous receptor signaling by S1P, these results may also identify novel point of cross-talk between cytokines and sphingolipids within endothelial signal transduction machineries.


Asunto(s)
Caveolina 1/biosíntesis , Células Endoteliales/metabolismo , Lisofosfolípidos/metabolismo , Transducción de Señal/fisiología , Esfingosina/análogos & derivados , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Bovinos , Movimiento Celular/fisiología , Células Cultivadas , Regulación hacia Abajo , Immunoblotting , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Interferente Pequeño , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esfingosina/metabolismo
5.
J Perinat Med ; 35(5): 447-54, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17685857

RESUMEN

AIM: To evaluate factors affecting survival and long-term outcome of extremely premature infants and to determine whether small for gestational age (SGA) status is an additional risk factor. METHODS: Survival was analyzed in 193 infants born between 23 and 27 weeks of gestational age (GA) and compared between SGA (n=43) and appropriate for gestational age (AGA) infants. Long-term outcome was assessed in 123 infants at six years of chronological age by neurological evaluation and cognitive tests. RESULTS: The long-term survival rates were 72.1% for SGA and 84.0% for AGA infants. Significant independent factors affecting survival were GA (OR 1.79 for one week advance, 95% CI 1.36-2.34) and SGA (OR 0.42, 95% CI 0.18-0.997) in comparison with AGA. There were no significant differences in rates of cerebral palsy or mental retardation, 12.0% and 24.0% in SGA, 14.3% and 17.3% in AGA, respectively. Fifty-two percent of SGA and 70% of AGA infants had intact long-term outcome. The perinatal factor found to affect the intact long-term outcome was RDS with surfactant therapy (OR 0.17, 95% CI 0.07-0.45). CONCLUSION: SGA status as well as short gestation had significant effects on survival. Respiratory complications after birth had a larger detrimental effect on long-term outcome than whether the infant was SGA or AGA.


Asunto(s)
Mortalidad Infantil , Recien Nacido Prematuro , Recién Nacido Pequeño para la Edad Gestacional , Niño , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Japón/epidemiología , Masculino , Enfermedades del Sistema Nervioso/congénito , Enfermedades del Sistema Nervioso/epidemiología , Embarazo , Segundo Trimestre del Embarazo
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