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1.
Placenta ; 35 Suppl: S4-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24321782

RESUMEN

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2013 there were twelve themed workshops, four of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of pregnancy pathologies and placental metabolism: 1) diabetes in pregnancy; 2) lipids, fatty acids and the placenta; 3) oxygen in placental development and pathologies; 4) stem cells and pathologies.


Asunto(s)
Diabetes Gestacional/metabolismo , Dislipidemias/fisiopatología , Oxígeno/fisiología , Placentación , Animales , Femenino , Desarrollo Fetal , Humanos , Embarazo , Transducción de Señal , Células Madre/fisiología
2.
Radiat Prot Dosimetry ; 136(3): 185-95, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19755434

RESUMEN

In order to investigate the exposure of operational personnel to radiofrequency electromagnetic fields when working for a mobile telephone operator, exposimeters were used to make individual records on 23 Technical Operations personnel (mobile telephone maintenance staff) and also on 22 Other Workers. The exposure densities, to which each of the 45 subjects was subjected, were quantified using 229 exposure indicators. Cluster analysis techniques were applied to the data, in an attempt to show that they would re-emerge as belonging to one of the two groups, i.e. the Technical Operational Personnel group or the Other Workers group. This exploratory investigation has shown that the cluster analysis does not reveal a sufficiently reliable emergence of the two groups, even though certain exposure indicators were significantly different for the two groups. In addition, the use of a Learning Group method does not lead to the discovery of a predictive law that could identify the Technical Operational Personnel as a sub-group within the overall group.


Asunto(s)
Carga Corporal (Radioterapia) , Teléfono Celular/estadística & datos numéricos , Microondas , Exposición Profesional/análisis , Exposición Profesional/estadística & datos numéricos , Monitoreo de Radiación/estadística & datos numéricos , Telecomunicaciones/estadística & datos numéricos , Francia , Humanos
3.
J Clin Microbiol ; 39(12): 4362-9, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11724846

RESUMEN

A real-time PCR assay was developed to quantify human cytomegalovirus (CMV) DNA in peripheral blood leukocytes (PBLs) of bone marrow transplantation patients. Unlike other teams, we quantified CMV and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene using a plasmid containing both sequences as an external standard. Tenfold serial dilutions of this plasmid yielded overlapping standard curves that allowed the quantification of CMV and GAPDH gene copies in an efficient and accurate manner. Sequential blood samples (164 specimens) were collected from 16 patients. PBLs were tested by the pp65 antigenemia assay and quantitative CMV and GAPDH gene PCRs. CMV DNA was detected by PCR in 13 patients a mean of 15 days prior to the appearance of antigenemia. The administration of anti-CMV drugs led to a rapid decrease in the numbers of viral copies and positive nuclei. Real-time PCR assay results correlated with those of the CMV pp65 antigenemia assay (P < 0.00001). The TaqMan assay may be a useful tool for rapid quantification of CMV infection and for monitoring of CMV reactivation in bone marrow transplantation recipients.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Infecciones por Citomegalovirus/virología , Citomegalovirus/aislamiento & purificación , ADN Viral/sangre , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Niño , Citomegalovirus/genética , Femenino , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Humanos , Masculino , Persona de Mediana Edad , Fosfoproteínas/sangre , Sensibilidad y Especificidad , Polimerasa Taq/metabolismo , Carga Viral , Proteínas de la Matriz Viral/sangre
4.
J Public Health Manag Pract ; 7(4): 23-37, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11434037

RESUMEN

This article describes the major activities associated with designing and implementing a comprehensive, professional development needs assessment of public health professionals in four states of the South Central region of the United States. The instrumentation, research design, and summary results of the needs assessment described in this article may facilitate similar efforts by interested researchers and program developers to assess the public health professional workforce training needs. Results of needs assessments can be useful in designing and evaluating professional development curricula and activities to strengthen public health services in the United States.


Asunto(s)
Evaluación de Necesidades , Administración en Salud Pública , Salud Pública/educación , Desarrollo de Personal , Adulto , Recolección de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Competencia Profesional , Desarrollo de Programa , Encuestas y Cuestionarios , Estados Unidos , Recursos Humanos
5.
Biochem Pharmacol ; 62(3): 329-34, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11434905

RESUMEN

The GnRH-R belongs to the superfamily of heptahelical GPCRs. A three-dimensional model of GnRH binding to its receptor predicted that Trp3 was the most deeply buried residue, potentially allowing it to interact with both Trp279, a highly conserved residue in the TMH 6 of GPCRs, and Phe310, present essentially in TMH 7 of GnRH-Rs. Replacement of Phe310 with Leu, the most common positional residue in GPCRs, induced a slightly decreased Bmax (1.6-fold) and affinity (3.8-fold); in addition, IP production was completely abolished. Similarly, replacement of Trp279 with Ser depressed the Bmax by 5.2-fold, the affinity by 2.3-fold, and totally abrogated IP production. The effect of the double mutation was not additive on binding, since the Bmax was reduced to the level of the Phe310Leu mutant, although the Kd was restored to a value not significantly different from that of the wild-type. The double mutant was also unable to induce IP production. Unexpectedly, no influence of any single or double substitution was noted on receptor internalization. These data provide evidence for the crucial role of Phe310, possibly in conjunction with Trp279, on GnRH transduction and suggest that the conformation for phospholipase C activation may not be required for GnRH-R internalization.


Asunto(s)
Proteínas de la Membrana/metabolismo , Receptores LHRH/metabolismo , Secuencia de Aminoácidos , Animales , Células CHO , Cricetinae , Humanos , Proteínas de la Membrana/química , Modelos Moleculares , Datos de Secuencia Molecular , Fenilalanina/metabolismo , Conformación Proteica , Ratas , Receptores LHRH/química , Homología de Secuencia de Aminoácido , Triptófano/metabolismo
7.
Opt Lett ; 26(17): 1344-6, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18049603

RESUMEN

Dark photorefractive photovoltaic spatial solitons are demonstrated at 532 nm in nominally undoped and slightly Fe-doped LiNbO(3) planar optical waveguides. The spatial solitons are observed in a transient regime before transverse modulation instability occurs. Their widths are intensity independent as predicted by theory. Meanwhile, excited mode distribution and Fe-doping concentration are shown to influence soliton width. The guiding properties of soliton-induced waveguides are also presented.

8.
J Clin Endocrinol Metab ; 85(9): 3002-8, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10999776

RESUMEN

We describe a woman with complete hypogonadotropic hypogonadism and a new compound heterozygous mutation of the GnRH receptor (GnRHR) gene. A null mutation L314X leading to a partial deletion of the seventh transmembrane domain of the GnRHR is associated with a Q106R mutation previously described. L314X mutant receptor shows neither measurable binding nor inositol phosphate production when transfected in CHO-K1 cells compared to the wild-type receptor. The disease is transmitted as an autosomal recessive trait, as shown by pedigree analysis. Heterozygous patients with GnRHR mutations had normal pubertal development and fertility. The present study shows an absence of LH and FSH response to pulsatile GnRH administration (20 microg/pulse, sc, every 90 min). However, GnRH triggered free alpha-subunit (FAS) pulses of small amplitude, demonstrating partial resistance to pharmacological doses of GnRH. FSH, LH, and FAS concentrations were evaluated under chronic estrogen treatment and repeat administration of GnRH. Not only were plasma FSH, LH, and FAS concentrations decreased, but FAS responsiveness was reduced. This new case emphasizes the implication of the GnRH receptor mutations in the etiology of idiopathic hypogonadotropic hypogonadism. We also have evidence for a direct negative estrogen effect on gonadotropin secretion at the pituitary level, dependent on the GnRHR signaling pathway.


Asunto(s)
Estrógenos/efectos adversos , Gonadotropinas/deficiencia , Hipogonadismo/genética , Mutación/genética , Receptores LHRH/genética , Secuencia de Aminoácidos , Animales , Células CHO , Niño , Cricetinae , Femenino , Hormona Folículo Estimulante/sangre , Hormonas Glicoproteicas de Subunidad alfa/sangre , Gonadotropinas/farmacología , Haplotipos , Humanos , Hormona Luteinizante/sangre , Datos de Secuencia Molecular , Fenotipo , Conformación Proteica , ARN Mensajero/biosíntesis , ARN Mensajero/genética
10.
Mol Pharmacol ; 57(3): 625-33, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10692505

RESUMEN

Previous studies have established that the interaction of gonadotropin-releasing hormone (GnRH) with its receptor (GnRHR) would require partial entry of the N- and C-terminal regions of ligand into the transmembrane core. The functional significance of the conserved aromatic residue Trp(279) present in the transmembrane helix 6, and Val(299) located in exoloop 3 of the rat GnRHR was investigated by mutagenesis followed by expression in Chinese hamster ovary-K1 cells. Compared with wild-type, substitution of Trp(279) with Ser or Arg resulted in a marked reduction or total abolition, respectively, of ligand binding and, in both cases, abrogation of GnRH-induced inositol phosphate production. A total absence of functionality was observed when Val(299) was simply replaced with Ala. Mention should be made that an expression of all mutated and wild-type receptor proteins was observed. Interestingly, the double mutant [Trp(279)Arg/Val(299)Ala]GnRHR restored B(max) to wild type (504 +/- 43 versus 541 +/- 41 fmol/mg protein), but with a diminished affinity (4.95 +/- 1.05 versus 0.94 +/- 0.35 nM), and GnRH failed to induce inositol phosphate. No influence of the mutations was seen on internalization of the receptor. The three-dimensional model of GnRH binding to the rat GnRHR was built predicting that Trp(279) is buried at 20 A in the transmembrane core of the receptor, directly in contact with Trp(3) of GnRH. In contrast, Val(299) is located in a region that cannot be precisely defined at the extracellular end of transmembrane helix 7. Although models cannot provide any clue concerning the observed interactivity between the two distal residues, altogether these data reveal the functional importance of both GnRHR Trp(279) and Val(299) and suggest that Trp(279), interacting with GnRH Trp(3), represents the bottom of the binding pocket.


Asunto(s)
Receptores LHRH/fisiología , Secuencia de Aminoácidos , Animales , Células CHO , Cricetinae , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Estructura Secundaria de Proteína , Ratas , Receptores LHRH/química , Receptores LHRH/genética , Homología de Secuencia de Aminoácido , Triptófano/fisiología , Valina/fisiología
11.
Teach Learn Med ; 12(4): 208-11, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11273371

RESUMEN

BACKGROUND: Medical educators are very interested in the teaching and evaluation of professional attitudes and behaviors among medical students, residents, and faculty. At Tulane University School of Medicine, we created the Program for Professional Values and Ethics in Medical Education (PPVEME) to return the focus of our curriculum to the physician-patient-community relationship and to the nurturing of professionalism. DESCRIPTION: PPVEME brings together students, residents, and faculty into learning teams that create longitudinal curricula about five themes: integrity, communication, teamwork, leadership, and service. The emphasis is on learner-driven self- and group-reflection about shared experiences, thus modeling essential professional attributes. EVALUATION: The program is evaluated using surveys, student and faculty focus groups, and portfolios developed by student volunteers on each team. The first program event, a retreat for entering medical students, was highly successful. CONCLUSIONS: PPVEME is an attempt to construct a medical school learning environment around professionalism. Evaluation over time will tell how successfully that has been accomplished.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Ética Médica/educación , Modelos Educacionales , Facultades de Medicina/organización & administración , Curriculum , Humanos , Louisiana , Desarrollo de Programa
12.
Teach Learn Med ; 12(4): 221-30, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11273373

RESUMEN

PURPOSE: Although MD-MPH programs exemplify the initiative for collaboration between schools of medicine and public health and address the expanding requirements for effective medical practice, information on such programs is scant. Perspectives and motivations of students enrolled in a 4-year MD-MPH program are explored to benefit existing and new programs as well as to inspire future research. SUMMARY: A questionnaire, based on previously identified themes, was mailed to all 110 students enrolled in the MD-MPH program at Tulane University. The typical respondent felt prepared for the program, expected to practice medicine full time, and expected to practice internationally up to 3 months annually. Perceived enhancements and barriers to dual degrees are addressed. CONCLUSIONS: Increased awareness of MD-MPH programs at the undergraduate level might be beneficial. Respondents valued the broader perspectives on the doctor-patient-society triad and additional career opportunities gained through their combined studies. Findings of this study can facilitate program planning and improvement elsewhere.


Asunto(s)
Educación de Pregrado en Medicina , Salud Pública/educación , Facultades de Medicina , Escuelas de Salud Pública , Estudiantes de Medicina/psicología , Adulto , Femenino , Humanos , Louisiana , Masculino , Encuestas y Cuestionarios
13.
J Clin Endocrinol Metab ; 84(3): 990-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10084584

RESUMEN

We have studied a kindred with three siblings with isolated hypogonadotropic hypogonadism caused by compound heterozygote mutations in the GnRH receptor gene. The disorder was transmitted as an autosomal recessive trait. The R262Q mutation in intracellular loop 3 of the receptor was associated with a mutation in the third transmembrane domain of the receptor, A129D, that has never been described before. This A129D mutation results in a complete loss of function, indicated by the lack of inositol triphosphate (TP3) 3 production by transfected Chinese hamster ovary (CHO) cells after GnRH stimulation. The two brothers had microphallus and bilateral cryptorchidism and were referred for lack of puberty, whereas their sister had primary amenorrhea and a complete lack of puberty. Their basal gonadotropin concentrations were below the reference range, and their endogenous LH secretory patterns were abnormal, with a low-normal frequency of small pulses or no apparent LH pulse. Pulsatile GnRH administration (10 microg/pulse every 90 min for 40 h) resulted in increased mean LH without any significant changes in testosterone levels in the two brothers, whereas the LH secretory profile of their sister remained apulsatile. Larger pulses of exogenous GnRH (20 microg every 90 min for 24 h) caused the sister to produce recognizable low amplitude LH pulses. The concentrations of free alpha-subunit significantly increased in all patients during the pulsatile GnRH administration. Thus, these hypogonadal patients are partially resistant to pulsatile GnRH administration, suggesting that they should be treated with gonadotropins to induce spermatogenesis or ovulation rather than with pulsatile GnRH.


Asunto(s)
Hormona Liberadora de Gonadotropina/uso terapéutico , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/genética , Mutación/fisiología , Receptores LHRH/genética , Adolescente , Adulto , Secuencia de Aminoácidos/genética , Animales , Células CHO , Cricetinae , ADN/genética , Resistencia a Medicamentos/fisiología , Femenino , Haplotipos , Humanos , Hormona Luteinizante/metabolismo , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Flujo Pulsátil
14.
Mol Cell Endocrinol ; 144(1-2): 95-108, 1998 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-9863630

RESUMEN

Several lines of evidence indicate that the number of GnRH receptors (GnRH-R) and therefore, gonadotrope responsiveness to GnRH, is highly dependent upon the level of GnRH-R mRNA. To explore this aspect of regulation, we have isolated a 3.3 kb fragment encompassing the promoter region of the rat GnRH-R gene. Primer extension and RNase protection assays allowed the identification of five major transcriptional start sites located within the 110 bp region upstream of the translation start codon. Transfection experiments using the CAT reporter gene demonstrated that the 1261 bp 5' flanking region is required to direct high efficient expression in the gonadotrope-derived alphaT3-1 cell line thus contrasting with mouse in which the only 500 bp proximal sequence appeared to be sufficient. Another difference between rat and mouse was apparent in the 183 bp region of the rat promoter which induced a 3-fold stimulation of thymidine kinase promoter activity in both alphaT3-1 and CHO cells. Subsequent deletion analysis of the region residing between -1261 and -519 revealed the presence of multiple regulatory domains that contributed to the cell-specific activity. However, despite this efficiency in the context of the wild-type promoter, they failed to induce the activity of the minimal thymidine kinase (TK) promoter in the absence of the proximal 600 bp promoter region. Accordingly, a composite TK promoter containing the entire 1.2 kb promoter induced a 10-fold increase in the activity of the TK promoter in alphaT3-1 cells. Taken together these data suggest that distal regulatory regions are critical and require cooperation with proximal specific-promoter elements for activating basal R-GnRH gene expression in gonadotrope cells.


Asunto(s)
Regulación de la Expresión Génica , Regiones Promotoras Genéticas/genética , Receptores LHRH/genética , Elementos de Respuesta/genética , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Cricetinae , Genes Reporteros , Modelos Genéticos , Datos de Secuencia Molecular , Especificidad de Órganos , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , Ratas , Alineación de Secuencia , Eliminación de Secuencia , Transcripción Genética/genética , Transfección
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