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Effect of leptin on the regulation of placental hormone secretion in cultured human placental cells.
Raquel Coya Pedro Martul Jaime Algorta Ma Angeles Aniel-Quiroga Ma Angeles Busturia Rosa Se?arís 《Gynecological endocrinology》2006,22(11):620-626
Placenta is an important source of leptin during pregnancy that contributes to the high plasma leptin levels in pregnant women. Leptin and its functional receptors are synthesized in trophoblast cells that, in turn, secrete gestational hormones supporting a paracrine or autocrine role for leptin in the endocrine activity of the placenta. In the present study we examined the effect of leptin on in vitro release of gestational hormones (human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone, estrogens and testosterone) by human term placental cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Progesterone, hCG, hPL, estradiol, estrone, estriol and testosterone levels were measured by different assays in culture media of cells maintained in monolayer culture after incubation for 12, 24, 48 or 72 h with leptin or placebo. Incubation with leptin did not modify hCG, hPL, progesterone, estriol and estrone secretion for any of the doses and times assayed. However, leptin led to a dose-dependent decrease in estradiol release. This effect was observed when treatment with recombinant human leptin spanned from 12 to 72 h. At this time an increase in testosterone levels was observed in leptin-treated cells versus placebo. These results indicate that leptin can be considered a gestational hormone implied in the endocrine function of the placenta, with an important role in control of the production of steroid reproductive hormones in placental cells in vitro. 相似文献
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A Cabrera M Sánchez M A Izquierdo E Pastor J M Galdeano S Mintegui M A Lizarraga A Cuadrado M Ca?ada 《Revista espa?ola de cardiología》1992,45(10):637-644
Between 1985-1990 we studied by means of two-dimensional echocardiography 286 patients with isolated ventricular septal defect (VSD). A hundred and sixty three being male and 123 female, as a mean age of 5 +/- 3 months. Sixty two cases (22.3%) reveales associated anomalies and in other 63 (22.4%) there was in the evolution an aneurysm of the septum membranous. The projections used were apical 4-chamber, with or without aortic root; parasternal long-short axis of great arterias or at ventricular level; subcostal 4-chamber; right oblique outlet right outflow tract and left oblique outlet left and right outflow tracts. Patients with VSD smaller than 3 mm were excluded. Perimembranous defects, 189 cases (66%), were more frequent than muscular, 91 31.8%), and subarterial defects, 6 (2.1%). Only 19 (9 apical muscular, 6 perimembranous outlet and 4 perimembranous trabecular) were initially misclassified. The diameter of the VSD was large in subarterial (0.85 +/- 0.1 cm) and perimembranous outlet VSD (0.75 +/- 0.5 cm) compared with the rest. Each group of defects was more easily shown by one particular projection except trabecular muscular defect. In conclusion, we are able to state that two-dimensional echocardiography enables us to discover the size and situation of isolated ventricular defects. 相似文献
5.
M Elena Garralda Francesco Muntoni Anna Cunniff Angeles Diaz Caneja 《European journal of paediatric neurology》2006,10(4):186-191
BACKGROUND: The use of knee ankle foot orthoses (KAFOs) to prolong independent mobility is a widely used rehabilitation strategy for children with Duchenne muscular dystrophy (DMD). AIMS: To explore views and adjustment of families with a child with Duchenne muscular dystrophy to the use of KAFOs. METHODS: interviews with families of children aged 8-18 years with DMD; questionnaires on psychiatric adjustment (SDQ for children; GHQ for parents). RESULTS: In total, 17 parents and 9 children took part. Families experienced the introduction of KAFOs as a signal for illness deterioration and a re-awakening of the feelings experienced at diagnosis. Nevertheless, the majority expressed a positive attitude and over two-thirds satisfaction with KAFOs use. High psychiatric risk was found in 2/17 children (12%; expected 10%) and 7/17 main carers (41%; expected 20-30%). CONCLUSION: Most families were satisfied with KAFOs use, and its implementation was well tolerated especially by the children. However, mental distress was high in main carers who emphasized the importance of full preparation and support in this rehabilitation technique. 相似文献
6.
A. Gustavo Gonzlez M. Angeles Herrador Agustín G. Asuero 《International journal of pharmaceutics》1995,120(2):215-220
The capacity factors (k′) of seven β-adrenoceptor blocking agents in six different reversed-phase HPLC systems have been determined. Octanol-aqueous buffer (pH 7.4) partition constants (P) for these blocking agents were also obtained. By using target factor analysis (TFA), good empirical correlations between the log k′ and log P were derived. The resulting hydrophobicity order agrees well with the metabolic elimination pathways of these drugs. 相似文献
7.
Antonio Cuadrado Emilio Fábrega Fernando Casafont Fernando Pons-Romero 《Liver transplantation》2005,11(4):420-426
The aim of this study was to evaluate the rate of alcohol recidivism after orthotopic liver transplantation (OLT) for alcoholic liver disease (ALD) and its influence on the allograft and patient survival, as well as the development of comorbidities and de novo cancers. The study was performed on 54 subjects previously analyzed and transplanted in our center for ALD, whose follow-up was prolonged to a mean of 99.2 (SD 31.7) months (range, 14-155). Medical records were reviewed, and data on alcohol consumption, therapeutic compliance, graft evolution, rejection, infections, comorbidities, rates of de novo malignancies and other clinical events, and survival were collected. Comparisons between groups were performed by the Fisher's exact test, and survival was assessed by the Kaplan-Meier method. Survival curves were compared using the Mantel-Cox statistic. The risk of death resulting from alcohol recidivism was analyzed with a Cox proportional hazards model. Fourteen patients who underwent transplantation for ALD (25.9%) returned to alcohol use between 5.0 and 86.9 months after OLT (median, 47.5). There was no significant association between the presence or absence of alcohol recidivism and the occurrence of graft rejection, infections, associated comorbidities after OLT, or compliance. The 5- and 10-year survival rates for patients with alcohol recidivism were 92.9% and 45.1%, respectively, compared with 92.4% and 85.5%, respectively, for patients without alcohol recidivism. These figures show significantly lower survival rates in recidivistic patients after 10 years (P < 0.01, Mantel-Cox). The fact that patients who resumed alcohol consumption have a worse 10-year survival rate might be attributed to a higher frequency of deaths, primarily from cancer and cardiovascular events. 相似文献
8.
Concepción González Inmaculada Pascual Angeles Bacete and Antonio Fimia 《Ophthalmic & physiological optics》1996,16(1):19-30
By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place ( S IL ), and the total spherical aberration of pseudophakic eyes ( S IT ). The optimum lens shapes for zero S IL and S IT or for minimum S IL and S IT of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is positive, the total Seidel spherical aberration of the whole eye cannot be zero but can only be minimized. If the power of the intraocular lens is negative, the total Seidel spherical aberration of the whole eye can be made zero, and one of the optimum lens shapes would be meniscus with the convex surface towards the retina. In addition to improving the quality of the image, the lens has advantages from the physiological point of view, since it helps to maintain the structure of the eye. 相似文献
9.
Pilar Bustamante Ma Angeles Pea Jerome Barra 《The Journal of pharmacy and pharmacology》1998,50(9):975-982
The expanded Hansen method was tested for determination of the solubility parameters of two non-steroidal anti-inflammatory drugs, naproxen and sodium diclofenac. This work describes for the first time the application of the method to the sodium salt of a drug. The original dependent variable of the expanded Hansen method, involving the activity coefficient of the drug, was compared with the direct use of the logarithm of the mole fraction solubility lnX2 in the solubility models. The solubility of both drugs was measured in pure solvents of several chemical classes and the activity coefficient was obtained from the molar heat and the temperature of fusion. Differential scanning calorimetry was performed on the original powder and on the solid phase after equilibration with the pure solvents, enabling detection of possible changes of the thermal properties of the solid phase that might change the value of the activity coefficient. The molar heat and temperature of fusion of sodium diclofenac could not be determined because this drug decomposed near the fusion temperature. The best results for both drugs were obtained with the dependent variable lnX2 in association with the four-parameter model which includes the acidic and basic partial-solubility parameters δa and δb instead of the Hansen hydrogen bonding parameter δh. Because the dispersion parameter does not vary greatly from one drug to another, the variation of solubility among solvents is largely a result of the dipolar and hydrogen-bonding parameters, a fact that is being consistently found for other drugs of small molecular weight. These results support earlier findings with citric acid and paracetamol that the expanded Hansen approach is suitable for determining partial-solubility parameters. The modification introduced in the expanded Hansen method, i.e. the use of lnX2 as the dependent variable, provides better results than the activity coefficient used in the original method. This is advantageous for drugs such as sodium diclofenac for which the ideal solubility cannot be estimated. This paper shows for the first time that the method is suitable for determination of the partial-solubility parameters of a sodium salt of a drug, sodium diclofenac. 相似文献
10.
The entire genome of SfV, a temperate serotype-converting bacteriophage of Shigella flexneri, has recently been sequenced (Allison, G.E., Angeles, D., Tran-Dinh, N., Verma, N.K. 2002, J. Bacteriol. 184, 1974-1987). Based on the sequence analysis, we further characterised the SfV virion structure and morphogenesis. Electron microscopy indicated that SfV belongs to the Myoviridae morphology family. Analysis of the proteins encoded by orf1, orf2, and orf3 revealed that they were homologous to small and large terminase subunits, and portal proteins, respectively; the protein encoded by orf5 showed homology to capsid proteins. Western immunoblot of the phage with anti-SfV sera revealed two antigenic proteins, and the N-terminal amino acid sequence of the 32-kDa protein corresponded to amino acids 116 to 125 of the ORF5 protein, suggesting that the capsid may be processed. Functional analysis of orf4 showed that it encodes the phage capsid protease. The proteins encoded by orfs1, 2, 3, 4, and 5 are homologous to similar proteins in the Siphoviridae phage family of both gram-positive and gram-negative origin. The capsid and morphogenesis genes are upstream and adjacent to the genes encoding Myoviridae (Mu-like) tail proteins. The organisation of the structural genes of SfV is therefore unique as the head and tail genes originate from different morphology groups. 相似文献