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1.
Urol Int ; 82(4): 481-3, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19506420

RESUMEN

We report 2 patients with epididymo-orchitis, caused by Brucella melitensis, accompanied by severe delay of diagnosis. In 1 patient the correct diagnosis was only suspected after his wife had been diagnosed with brucellosis. Our cases illustrate that diagnosing brucellosis can be difficult in nonendemic areas, especially when physicians are unfamiliar with it. Important clues pointing to brucellosis as cause of epididymo-orchitis are a travel history to endemic areas, unresponsiveness to empiric antibiotic treatment, and a preceding period of episodic subfebrile temperature, night sweats and fatigue. Serology is the diagnostic test of choice because it is faster and more sensitive than blood cultures. Delay of diagnosis may lead to serious complications. Therefore, alertness for brucellosis is warranted, also, if not especially, in nonendemic areas.


Asunto(s)
Brucelosis , Epididimitis/microbiología , Orquitis/microbiología , Adulto , Humanos , Masculino
2.
Int J Cardiol ; 100(2): 179-90, 2005 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-15823623

RESUMEN

Myocardial infarction is the major cause of death in the world. Over the last two decades, coronary reperfusion therapy has become established for the management of acute myocardial infarction (AMI). However, restoration of blood flow to previously ischemic myocardium results in the so-called ischemia/reperfusion (IR)-injury. The different clinical manifestations of this injury include myocardial necrosis, arrhythmia, myocardial stunning and endothelial- and microvascular dysfunction including the no-reflow phenomenon. The pathogenesis of ischemia/reperfusion injury consists of many mechanisms. Recently, there's increasing evidence for an important role in IR-injury on hypercontracture induced by high levels of cytosolic calcium or by low concentrations of ATP. In the last years, many studies on experimental models were investigated, but the clinical trials confirming these effects remain spare. Recently, the beneficial effect of Na(+)/H(+)-exchange inhibitor cariporide and of the oxygen-derived free radical (ODFR) scavenger vitamin E on coronary bypass surgery-induced IR-injury were demonstrated. Also recently, the beneficial effect of allopurinol on the recovery of left ventricular function after rescue balloon-dilatation was demonstrated. The beneficial effect of magnesium and trimetazidine on IR-injury remains controversial. The beneficial effect of adenosine remains to be further confirmed. There's also increasing interest in agentia combining the property of upregulating NO-synthase (e.g. L-arginine) and restoring the balance between NO and free radicals (e.g. tetrahydrobiopterin). One of such agents could be folic acid. In this review article the authors give an overview of the recent insights concerning pathogenesis and therapeutic possibilities to prevent IR-induced injury.


Asunto(s)
Daño por Reperfusión Miocárdica/fisiopatología , Calcio/metabolismo , Endotelio Vascular/fisiopatología , Radicales Libres , Humanos , Infarto del Miocardio/terapia , Isquemia Miocárdica/fisiopatología , Daño por Reperfusión Miocárdica/terapia
3.
Theriogenology ; 46(5): 871-80, 1996 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-16727950

RESUMEN

Nuclear transfer was used to study nuclear reprogramming of fetal diploid bovine germ cells collected at two stages of the fetal development. In the first case, germ cells of both sexes were collected during their period of intragonadal mitotic multiplication at 48 days post coïtum (d.p.c.). In the second case, only male germ cells were collected after this period, between 105 and 185 d.p.c. Isolated germ cells were fused with enucleated oocytes. Reconstituted embryos were cultured in vitro and those reaching the compacted morula or blastocyst stage were transferred into synchronous recipient heifers. Of 511 reconstituted embryos with 48 d.p.c. germ cells (309 males and 202 females), 48% (247/511 ) cleaved; 2.7% (14/511 ) reached the compacted morula stage and 8 of them the blastocyst stage (1.6%). No difference was observed between sexes. All 14 compacted morulae/blastocysts were transferred into 6 recipients and one pregnancy was initiated. This recipient was slaughtered at Day 35 and an abnormal conceptus (extended trophectoderm and degenerated embryo) was collected. Its male sex, genetically determined, corresponded to that of donor fetus. Of 380 reconstituted embryos with male 105 to 185 d.p.c. germ cells, 72.1% (274/380 ) cleaved, 2.1% (8 380 ) reached the compact morula stage and 7 of these the blastocyst stage (1.8%). Three blastocysts and one morula were transferred into 4 recipients. Two became pregnant at Day 21 but only one at Day 35 which aborted around Day 40. Our results show that the nucleus of diploid bovine germ cells of both sexes can be reprogrammed. However, in the absence of further development of these reconstituted embryos, nuclear totipotency of bovine diploid germ cells remains to be evidenced.

4.
Appl Radiat Isot ; 87: 229-32, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24355303

RESUMEN

Multi-layer (235)UF4-(6)LiF-Au targets have been produced by vacuum deposition on thin polyimide foils with an areal density, measured by spectrophotometry, of about 33µgcm(-2). The foils were first covered with an Au-layer and then, with a second layer of (6)LiF, both by vapour deposition. The (235)UF4 layer was prepared by fluoride sublimation. Each deposited mass was characterized separately by means of differential weighing for the Au and (6)LiF layers and by low-geometry alpha-particle counting for the (235)UF4 layer. The atomic abundances of the uranium base material have been measured by thermal ionization mass spectrometry. The targets were prepared for measuring fission-fragment emission yields with high mass-resolution.

5.
Appl Radiat Isot ; 87: 238-41, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24373873

RESUMEN

The methods of electrodeposition and "molecular plating" were studied for the production of uranium targets with an areal density up to 0.6 mg cm(-2) on aluminium and up to 1.5 mg cm(-2) on stainless steel backings from aqueous and organic electrolytes. For characterisation of the deposited material, gamma-ray spectrometry, alpha-particle spectrometry, X-ray fluorescence, X-ray powder diffraction, scanning electron microscopy and autoradiography were applied.

6.
Am J Physiol Heart Circ Physiol ; 292(1): H387-91, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16963614

RESUMEN

To study the role of early energetic abnormalities in the subsequent development of heart failure, we performed serial in vivo combined magnetic resonance imaging (MRI) and (31)P magnetic resonance spectroscopy (MRS) studies in mice that underwent pressure-overload following transverse aorta constriction (TAC). After 3 wk of TAC, a significant increase in left ventricular (LV) mass (74 +/- 4 vs. 140 +/- 26 mg, control vs. TAC, respectively; P < 0.000005), size [end-diastolic volume (EDV): 48 +/- 3 vs. 61 +/- 8 microl; P < 0.005], and contractile dysfunction [ejection fraction (EF): 62 +/- 4 vs. 38 +/- 10%; P < 0.000005] was observed, as well as depressed cardiac energetics (PCr/ATP: 2.0 +/- 0.1 vs. 1.3 +/- 0.4, P < 0.0005) measured by combined MRI/MRS. After an additional 3 wk, LV mass (140 +/- 26 vs. 167 +/- 36 mg; P < 0.01) and cavity size (EDV: 61 +/- 8 vs. 76 +/- 8 microl; P < 0.001) increased further, but there was no additional decline in PCr/ATP or EF. Cardiac PCr/ATP correlated inversely with end-systolic volume and directly with EF at 6 wk but not at 3 wk, suggesting a role of sustained energetic abnormalities in evolving chamber dysfunction and remodeling. Indeed, reduced cardiac PCr/ATP observed at 3 wk strongly correlated with changes in EDV that developed over the ensuing 3 wk. These data suggest that abnormal energetics due to pressure overload predict subsequent LV remodeling and dysfunction.


Asunto(s)
Adenosina Trifosfato/metabolismo , Cardiomiopatía Hipertrófica/metabolismo , Metabolismo Energético , Hipertrofia Ventricular Izquierda/metabolismo , Contracción Miocárdica , Fosfocreatina/metabolismo , Disfunción Ventricular Izquierda/metabolismo , Animales , Cardiomiopatía Hipertrófica/complicaciones , Hipertrofia Ventricular Izquierda/etiología , Masculino , Tasa de Depuración Metabólica , Ratones , Ratones Endogámicos C57BL , Disfunción Ventricular Izquierda/etiología , Remodelación Ventricular
7.
Sch Inq Nurs Pract ; 15(3): 223-33, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11871581

RESUMEN

Adherence to treatment is a major issue for people with diabetes mellitus, and attention has been given to improving self-management in persons with this chronic disease. Most studies show that knowledge alone will not improve self-management behavior. Self-efficacy, a concept introduced by Bandura, has been shown to be an important variable in improving health behaviors. In order to determine whether self-efficacy can influence self-management of diabetes, however, instruments to measure self-efficacy are needed in native languages at an appropriate developmental level, and with good psychometric properties. The study reported here was part of a larger project in the Netherlands, Belgium and the United States in which several instruments, measuring diabetes management self-efficacy, have been developed, both in English and Dutch, for different types of diabetes and different age groups. This article reports on the development and psychometric testing of an instrument measuring self-efficacy in adolescents with type 1 diabetes mellitus. Initially 30 items for the instrument were generated through focus group interviews and their relevance was judged by a team of 10 experts on self-management behavior in adolescents. The final instrument contained 26 items. The sample for psychometric testing consisted of 90 patients with type 1 diabetes who were between 12 and 18 years old. Cronbach's alpha of the instrument was 0.86. An exploratory factor analysis produced two factors which reflect general and more difficult diabetes self-management situations.


Asunto(s)
Diabetes Mellitus Tipo 1/enfermería , Evaluación en Enfermería/métodos , Autocuidado , Autoeficacia , Encuestas y Cuestionarios , Adolescente , Bélgica , Diabetes Mellitus Tipo 1/psicología , Análisis Factorial , Femenino , Humanos , Masculino , Países Bajos , Reproducibilidad de los Resultados , Estados Unidos
8.
Mol Reprod Dev ; 43(1): 38-46, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8720111

RESUMEN

The potential pluripotency of rabbit fetal germ cells has been investigated by using them to make chimeric embryos. Gonial cells, isolated from enzyme-dispersed male and female transgenic fetal rabbit gonads of 18-22 days gestation, were microinjected in groups of about 10 into 640 nontransgenic rabbit embryos between the two-cell and expanded blastocyst stages. Injections were made with primary isolations of gonial cells, within 48 hr of their collection. The injected embryos were transferred, with or without non-injected control embryos, into 49 recipient rabbits. Tissues from 159 resulting fetuses, implantation sites, and a few liveborn young were examined by PCR analysis for the two transgenes used (alpha-1 antitrypsin or luciferase). The overall pregnancy rate (about 80%) was not affected by the stage of development of the embryo injected, nor by co-transfer of control embryos. The survival rate of injected embryos (18% overall, 23.6% in pregnant recipients) was almost identical to that of 243 control embryos. Chimerism was detectable in tissues produced from 4 of 159 (2.5%) of the injected embryos, all four of which had been injected at the 8- to 16-cell stage. This low rate of success indicates that, although passage of rabbit gonial cells is not an absolute requirement for pluripotency, further investigation should pay particular attention to improving culture conditions with a view to deriving EG cell lines.


Asunto(s)
Blastocisto/fisiología , Quimera , Desarrollo Embrionario y Fetal , Trasplante de Tejido Fetal , Feto/fisiología , Animales , Animales Modificados Genéticamente , Blastocisto/citología , Células Cultivadas , Femenino , Masculino , Microinyecciones , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Mórula/citología , Mórula/fisiología , Ovario/embriología , Ovario/trasplante , Ovario/ultraestructura , Testículo/embriología , Testículo/trasplante , Testículo/ultraestructura
9.
Hum Reprod ; 15(4): 756-61, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10739815

RESUMEN

Collection of human term placentae for research purposes is generally limited during working hours. Preserving placental tissue overnight might help to postpone experiments and, by extent, to increase material availability. In this study, fragments from normal placentae were incubated at 37 degrees C either immediately after delivery or after preservation at 4 degrees C in a HEPES-buffered solution or in a Roswell Park Memorial Institute (RPMI) 1640 culture medium. Protein, human chorionic gonadotrophin (HCG), human placental lactogen (HPL) and lactate dehydrogenase (LDH) contents within preserved explants were similar to those within freshly delivered ones. In contrast, HCG and HPL amounts released during incubation of preserved tissue were lower than with freshly delivered tissue. Differences were significant only during the first 3 h of incubation. Hormone releases were similarly Ca(2+)-stimulated, and Co(2+)- and low temperature-inhibited in preserved and freshly delivered tissues. After preservation, LDH leakage was also reduced. Furthermore, before and after 37 degrees C incubation during 6 h, preserved tissue was morphologically indistinguishable from freshly delivered tissue and showed neither higher incidence of DNA fragmentation, nor elevated caspase-3 activity, both of which are markers of apoptosis. This study validates an original, useful and rapid method to preserve placental tissue. Consequently, this preservation model may facilitate the study of physiological processes regulating placental hormone secretion in normal and pathological conditions.


Asunto(s)
Frío , Placenta/fisiología , Conservación de Tejido , Apoptosis , Tampones (Química) , Calcio/farmacología , Caspasa 3 , Caspasas/análisis , Gonadotropina Coriónica/análisis , Gonadotropina Coriónica/metabolismo , Cobalto/farmacología , Medios de Cultivo , Fragmentación del ADN , Femenino , Humanos , Etiquetado Corte-Fin in Situ , L-Lactato Deshidrogenasa/análisis , L-Lactato Deshidrogenasa/metabolismo , Placenta/efectos de los fármacos , Placenta/metabolismo , Lactógeno Placentario/análisis , Lactógeno Placentario/metabolismo , Embarazo , Proteínas/análisis , Factores de Tiempo
10.
Zygote ; 10(3): 189-99, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12214799

RESUMEN

Although toxic for early stages of embryo development, glucose is a physiological metabolic substrate at the morula and blastocyst stages. We evaluated the effect of adding 5.5 mM glucose from the morula stage on bovine blastocyst development and quality. In vitro matured and fertilised bovine oocytes were cultured in modified Synthetic Oviduct Fluid medium containing 5% fetal calf serum, but without added glucose, up to day 5 post-insemination (pi). Morulae were selected and further cultured in the presence or absence of 5.5 mM glucose. Blastocyst and hatched blastocyst rates were recorded. Oxygen, glucose and pyruvate uptakes as well as lactate release were evaluated. The quality of the resulting blastocysts was evaluated by the cell allocation to the inner cell mass (ICM) and trophectoderm (TE) and by the apoptotic index. Adding glucose increased the blastocyst rate at day 8 pi (80% vs 65%) but had no impact on hatching rate (25% vs 28%). A 22% decrease in oxygen uptake was observed in the presence of glucose, concomitant with an increase in lactate release, although no change was observed in pyruvate uptake. A slight decrease in blastocyst cell number was observed at day 7 in the presence of glucose while neither the ICM/TE cell ratio nor the apoptotic index were affected. In conclusion, adding 5.5 mM glucose from the morula stage has a limited impact on blastocyst rate and quality although important modifications were observed in embryo metabolism. It remains to be determined whether those modifications could influence embryo viability after transfer.


Asunto(s)
Desarrollo Embrionario y Fetal/efectos de los fármacos , Glucosa/farmacología , Animales , Apoptosis/efectos de los fármacos , Blastocisto/citología , Blastocisto/efectos de los fármacos , Blastocisto/metabolismo , Bovinos , Medios de Cultivo , Desarrollo Embrionario y Fetal/fisiología , Metabolismo Energético/efectos de los fármacos , Fertilización In Vitro , Glucosa/metabolismo , Técnicas In Vitro , Ácido Láctico/metabolismo , Mórula/citología , Mórula/efectos de los fármacos , Mórula/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Ácido Pirúvico/metabolismo
11.
Biol Reprod ; 61(2): 458-63, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10411527

RESUMEN

Apoptosis in human placental villi is reported to increase until close to delivery. However, the involvement of the apoptotic process in the initiation of labor, and more particularly in relation to the decrease in placental perfusion during uterine contractions, remains unknown. The purpose of the study was to examine the reactivity of the apoptotic machinery in term placentae obtained before or after the onset of labor and after in vitro incubations. The incidence of apoptotic nuclei (< 1%) as evidenced by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method, and the histological distribution of immunoreactive Bcl-2, Bax, and Bcl-x proteins, were similar in placentae collected after delivery and before the onset of labor and in placental explants maintained overnight at 4 degrees C in a minimal salt-Hepes medium. By contrast, 28% of nuclei contained fragmented DNA when placental explants were incubated overnight at 37 degrees C. This marked increase was associated with a decrease in the intensity of the Bcl-2 immunostaining and an increase in the intensity of Bax and Bcl-x immunostaining. In conclusion, the present study clearly evidences the presence of an active apoptotic machinery in term placental cells that is not involved in normal parturition.


Asunto(s)
Apoptosis , Trabajo de Parto/fisiología , Placenta/fisiología , Medios de Cultivo , Fragmentación del ADN , Femenino , Humanos , Inmunohistoquímica , Técnicas In Vitro , Embarazo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis
12.
Differentiation ; 60(5): 339-45, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8855377

RESUMEN

The pluri- or totipotency of gonial cells, isolated from rabbit fetuses at 18-20 days of pregnancy, has been investigated by transferring their nuclei into enucleated oocytes and following the development of the resulting reconstituted embryos both in vitro (in a total of 726 embryos) and in vivo (in 135 embryos). The gonial cells exhibited pseudopodial activity like that of primordial germ cells and ultrastructural studies confirmed that neither male nor female cells had entered meiosis. When the gonial cells were used immediately after isolation, about 37% of the reconstituted embryos of both sexes cleaved, with no significant difference according to sex. However, after a further 4-day culture of the cleaved embryos, the blastocyst formation rate was four times higher in those made with male (16%) than with female (4%) gonial cells. No implantation sites were detected following transfer of reconstituted embryos into recipient females. These results show that the nuclei of male and female rabbit diploid germ cells differ in their capability to be "reprogrammed" and bring about development to the blastocyst stage following nuclear transfer. The origin of this difference, which is evidenced long before the onset of meiosis is discussed.


Asunto(s)
Núcleo Celular/fisiología , Células Germinativas/fisiología , Técnicas de Transferencia Nuclear , Conejos/fisiología , Caracteres Sexuales , Animales , Células Cultivadas , Diploidia , Transferencia de Embrión , Desarrollo Embrionario y Fetal , Femenino , Células Germinativas/citología , Gónadas/citología , Gónadas/embriología , Masculino , Embarazo , Diferenciación Sexual
13.
Zygote ; 5(1): 47-60, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9223245

RESUMEN

Germ cells were isolated from rabbit fetal gonads between 18 and 22 days post coitum and examined morphologically, ultrastructurally and for immunocytochemical and cytochemical characteristics. Observations were compared with the information available from the corresponding cells of other mammalian species. The general morphology and ultrastructure of healthy isolated rabbit fetal germ cells were found to be very similar to those of the rabbit and mouse diploid germ cells in situ. Moreover, rabbit fetal germ cells shared common immunocytochemical characteristics with mouse undifferentiated embryonic stem cells or embryonic carcinoma cells, such as the presence of TEC-1 (SSEA-1) antigens, a peripheral network of F-actin, the absence of cytokeratins 8/18 and lamins A/C and an alkaline phosphatase activity. No difference between the sexes was observed. Morphological and physiological similarities with the migrating and cultured primordial germ cells of the mouse also suggest that diploid rabbit germ cells would be good candidates for deriving pluripotential embryonic germ cells (EG cells) if favourable culture conditions could be found. In conclusion, the rabbit may be a suitable model for investigations on EG cells in domestic mammals with delayed meiosis.


Asunto(s)
Gónadas/embriología , Óvulo/ultraestructura , Espermatozoides/ultraestructura , Fosfatasa Alcalina/metabolismo , Animales , Diferenciación Celular , Células Cultivadas , Diploidia , Femenino , Gónadas/citología , Inmunohistoquímica , Masculino , Microscopía Electrónica , Óvulo/enzimología , Óvulo/metabolismo , Embarazo , Conejos , Espermatozoides/enzimología , Espermatozoides/metabolismo
14.
Biol Reprod ; 56(1): 194-9, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9002649

RESUMEN

The pluripotency of embryonic germ cells in the mouse suggests that mitotic bovine fetal germ cells might also be a source of pluripotent cells. To investigate the pluripotency of bovine oogonia, the development in vitro of bovine embryos reconstructed by fusing oogonia with enucleated oocytes was compared with that of embryos made similarly with either blastomeres or granulosa cells. The donor cells (fresh oogonia, cryopreserved oogonia, 16- to 32-cell-stage blastomeres, or granulosa cells) were fused to the enucleated oocytes electrically. The proportions of reconstructed embryos that had cleaved at 40 h after fusion using these types of donor cells were not significantly different (37%, 33%, 56%, and 31%, respectively; p > 0.05). However, the proportions of cleaved reconstructed embryos that developed to the blastocyst stage were 9%, 13%, 36%, and 3%, respectively, significantly higher (p < or = 0.05) with blastomeres than with the other three types of donor cells. After transfer of 3 morulae and 4 blastocysts made with oogonia into three recipient heifers, embryonic and extra-embryonic tissues developed in one animal. On recovery after 43 days gestation, this conceptus was shown to be genetically identical, at 11 microsatellite loci, to the fetus that had provided the oogonia. Cytological analysis of the embryos made with oogonia at 40-44 h after fusion and at the morula and blastocyst stages revealed that aberrant cytokinesis and nucleokinesis had given rise to multinucleated, anucleate, and polyploid cells in the reconstructed embryos. It is concluded that limited pluripotency of bovine oogonia has been demonstrated, warranting further study in this area.


Asunto(s)
Desarrollo Embrionario y Fetal , Técnicas de Transferencia Nuclear , Oocitos/ultraestructura , Oogonios , Animales , Blastocisto/fisiología , Blastómeros/fisiología , Bovinos , Recuento de Células , Fusión Celular , Técnicas de Cultivo , Diploidia , Transferencia de Embrión , Embrión de Mamíferos/ultraestructura , Femenino , Mórula/fisiología
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