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1.
Balkan J Med Genet ; 25(1): 41-50, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36880035

RESUMEN

Multiple sclerosis (MS) is an inflammatory disease characterized by demyelination and axonal degeneration affecting the central nervous system. Among the genetic factors suggested to be associated with this disease are polymorphisms to the vitamin D receptor (VDR) gene. We tested the hypothesis that polymorphisms in the vitamin D receptor (VDR) gene are associated with MS. The aim of the study was to investigate the relationship of MS with the VDR gene Fok-I, Bsm-I and Taq-I polymorphisms among the Turkish population. This study contains 271 MS patients and 203 healthy controls. Genomic DNA was isolated from the samples and the VDR gene Fok-I, Bsm-I and Taq-I polymorphism regions were amplified by polymerase chain reaction (PCR). The PCR products were digested, and the genotypes were determined based on size of digested PCR products. Our results demonstrate associations between MS and the distribution of the VDR gene Fok-I T/T polymorphism genotype in a dominant model, VDR gene Fok-I T allele frequency, distribution of VDR gene Taq-I C/C polymorphism genotype in a dominant model and VDR gene Taq-I C allele frequency (Pearson test, p<0.05). However, there was no association between MS and the VDR gene Bsm-I polymorphisms for the genotype distribution (Pearson test, p>0.05) or allele frequency (Pearson test, p>0.05). Fok-I and Taq-I VDR gene polymorphisms are significantly associated with MS in dominant, homozygote and heterozygote inheritance models among the Turkish population.

2.
Int J Obes (Lond) ; 37(8): 1088-94, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23229739

RESUMEN

OBJECTIVE: With the increasing rates of obesity, many people diet in an attempt to lose weight. As weight loss is seldom maintained in a single effort, weight cycling is a common occurrence. Unfortunately, reports from clinical studies that have attempted to determine the effect of weight cycling on mortality are in disagreement, and to date, no controlled animal study has been performed to assess the impact of weight cycling on longevity. Therefore, our objective was to determine whether weight cycling altered lifespan in mice that experienced repeated weight gain and weight loss throughout their lives. METHODS: Male C57BL/6J mice were placed on one of three lifelong diets: a low-fat (LF) diet, a high-fat (HF) diet or a cycled diet in which the mice alternated between 4 weeks on the LF diet and 4 weeks on the HF diet. Body weight, body composition, several blood parameters and lifespan were assessed. RESULTS: Cycling between the HF and LF diet resulted in large fluctuations in body weight and fat mass. These gains and losses corresponded to significant increases and decreases, respectively, in leptin, resistin, GIP, IGF-1, glucose, insulin and glucose tolerance. Surprisingly, weight cycled mice had no significant difference in lifespan (801±45 days) as compared to LF-fed controls (828±74 days), despite being overweight and eating a HF diet for half of their lives. In contrast, the HF-fed group experienced a significant decrease in lifespan (544±73 days) compared with LF-fed controls and cycled mice. CONCLUSIONS: This is the first controlled mouse study to demonstrate the effect of lifelong weight cycling on longevity. The act of repeatedly gaining and losing weight, in itself, did not decrease lifespan and was more beneficial than remaining obese.


Asunto(s)
Dieta con Restricción de Grasas , Dieta Alta en Grasa , Leptina/metabolismo , Longevidad , Obesidad/patología , Aumento de Peso , Pérdida de Peso , Animales , Péptido C/metabolismo , Quimiocina CCL2/metabolismo , Ingestión de Energía , Polipéptido Inhibidor Gástrico/metabolismo , Insulina/metabolismo , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/mortalidad , Fragmentos de Péptidos/metabolismo , Resistina/metabolismo , Factores de Tiempo
4.
Anaesthesist ; 61(12): 1049-53, 2012 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-23223840

RESUMEN

This case report of a silent cardiotocogram (CTG) registration during general anesthesia in a 33-week-pregnant patient undergoing non-obstetric surgery demonstrates the possibility of misinterpretation whereby typical CTG patterns of fetal reactions to anesthetics can be misinterpreted as fetal hypoxia or even asphyxia.


Asunto(s)
Anestesia General/efectos adversos , Cardiotocografía , Cesárea , Adulto , Femenino , Hipoxia Fetal/diagnóstico , Monitoreo Fetal , Frecuencia Cardíaca/fisiología , Frecuencia Cardíaca Fetal , Humanos , Imagen por Resonancia Magnética , Polirradiculopatía/cirugía , Embarazo
5.
Diabetologia ; 52(8): 1647-55, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19468705

RESUMEN

AIMS/HYPOTHESIS: Growth hormone has been used experimentally in two studies to treat individuals with type 2 diabetes, with both reporting beneficial effects on glucose metabolism. However, concerns over potential diabetogenic actions of growth hormone complicate its anticipated use to treat type 2 diabetes. Thus, an animal model of type 2 diabetes could help evaluate the effects of growth hormone for treating this condition. METHODS: Male C57BL/6J mice were placed on a high-fat diet to induce obesity and type 2 diabetes. Starting at 16 weeks of age, mice were treated once daily for 6 weeks with one of four different doses of growth hormone. Body weight, body composition, fasting blood glucose, insulin, glucose tolerance, liver triacylglycerol, tissue weights and blood chemistries were determined. RESULTS: Body composition measurements revealed a dose-dependent decrease in fat and an increase in lean mass. Analysis of fat loss by depot revealed that subcutaneous and mesenteric fat was the most sensitive to growth hormone treatment. In addition, growth hormone treatment resulted in improvement in glucose metabolism, with the highest dose normalising glucose, glucose tolerance and liver triacylglycerol. In contrast, insulin levels were not altered by the treatment, nor did organ weights change. However, fasting plasma leptin and resistin were significantly decreased after growth hormone treatment. CONCLUSIONS/INTERPRETATION: Growth hormone therapy improves glucose metabolism in this mouse model of obesity and type 2 diabetes, providing a means to explore the molecular mechanism(s) of this treatment.


Asunto(s)
Glucemia/metabolismo , Composición Corporal/efectos de los fármacos , Diabetes Mellitus Tipo 2/metabolismo , Hormona del Crecimiento/uso terapéutico , Hígado/metabolismo , Triglicéridos/metabolismo , Tejido Adiposo/anatomía & histología , Tejido Adiposo/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/fisiopatología , Grasas de la Dieta/farmacología , Modelos Animales de Enfermedad , Hormona del Crecimiento/administración & dosificación , Inyecciones Subcutáneas , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Obesidad/fisiopatología
6.
Aliment Pharmacol Ther ; 47(1): 6-15, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28994131

RESUMEN

BACKGROUND: The Inflammatory Bowel Disease Disability Index (IBD-DI) has recently been developed for patients with Crohn's disease (CD) and ulcerative colitis (UC). AIM: To assess the severity of disability and associated factors using the IBD-DI, and review the validity of the IBD-DI as a tool. METHOD: Systematic review of cross-sectional studies. Patients included had UC or CD and were classified as active, in remission, or needing surgery, biological and/or steroid treatment. We included studies assessing disability using the IBD-DI and that were captured by electronic and manual searches (January 2017). The possibility of bias was evaluated with the Newcastle-Ottawa Scale. RESULTS: Nine studies were included with 3167 patients. Comparatively, patients with active disease had higher disability rates than those in remission (SMD [CI95] = 1.49[1.11, 1.88], I2  = 94%, P<.01), while patients on biological treatment had lower disability rates than those receiving corticosteroid treatment (SMD [CI95] = -0.22[-0.36, -0.08], I2  = 0%, P<.01). Disease activity and unemployment were found to be associated factors. The IBD-DI scored "good" for internal consistency, "fair" to "excellent" for intra-rater reliability and "excellent" for inter-rater reliability. Construct validity was "moderately strong" to "very strong" and structural validity was found to be mainly unidimensional. The IBD-DI had excellent responsiveness, while its interpretability was only useful on a group level. CONCLUSIONS: This systematic review and meta-analysis found a significant association between disease activity, treatment received and disability; although significant heterogeneity was found. The IBD-DI is reliable and valid, but further studies are needed to measure its interpretability.


Asunto(s)
Colitis Ulcerosa/fisiopatología , Enfermedad de Crohn/fisiopatología , Personas con Discapacidad , Estudios Transversales , Humanos , Reproducibilidad de los Resultados
7.
Endocrinology ; 156(4): 1362-71, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25646711

RESUMEN

Patients with acromegaly have a higher prevalence of vertebral fractures despite normal bone mineral density (BMD), suggesting that GH overexpression has adverse effects on skeletal architecture and strength. We used giant bovine GH (bGH) transgenic mice to analyze the effects of high serum GH levels on BMD, architecture, and mechanical strength. Five-month-old hemizygous male bGH mice were compared with age- and sex-matched nontransgenic littermates controls (NT; n=16/group). Bone architecture and BMD were analyzed in tibia and lumbar vertebrae using microcomputed tomography. Femora were tested to failure using three-point bending and bone cellular activity determined by bone histomorphometry. bGH transgenic mice displayed significant increases in body weight and bone lengths. bGH tibia showed decreases in trabecular bone volume fraction, thickness, and number compared with NT ones, whereas trabecular pattern factor and structure model index were significantly increased, indicating deterioration in bone structure. Although cortical tissue perimeter was increased in transgenic mice, cortical thickness was reduced. bGH mice showed similar trabecular BMD but reduced trabecular thickness in lumbar vertebra relative to controls. Cortical BMD and thickness were significantly reduced in bGH lumbar vertebra. Mechanical testing of femora confirmed that bGH femora have decreased intrinsic mechanical properties compared with NT ones. Bone turnover is increased in favor of bone resorption in bGH tibia and vertebra compared with controls, and serum PTH levels is also enhanced in bGH mice. These data collectively suggest that high serum GH levels negatively affect bone architecture and quality at multiple skeletal sites.


Asunto(s)
Densidad Ósea/genética , Huesos/metabolismo , Hormona del Crecimiento/genética , Animales , Peso Corporal/genética , Hormona del Crecimiento/metabolismo , Masculino , Ratones , Ratones Transgénicos , Estrés Mecánico
8.
Gene ; 202(1-2): 15-21, 1997 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-9427540

RESUMEN

The v-ski oncogene was introduced into mammalian cells in order to study its biochemical and biological properties. v-Ski, produced at relatively high levels by mouse L cells stably transfected with this DNA, was localized to the cell nucleus, was of correct apparent molecular mass, and was capable of complexing with DNA. Transient transfection of reporter plasmids into control or Ski producing mouse L cells revealed that Ski acts as a transcriptional activator of various transcriptional regulatory elements, including CMVie, RSV LTR and SV40. These results indicate that mouse L cells contain the nuclear cofactor(s) required for the ability of v-Ski to bind to DNA and also suggest that the v-Ski present within the cells is functional.


Asunto(s)
Proteínas Oncogénicas de Retroviridae/biosíntesis , Proteínas Oncogénicas de Retroviridae/química , Factores de Transcripción , Animales , Técnicas de Cultivo de Célula , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Células L , Ratones , Peso Molecular , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/química , Proteínas Nucleares/fisiología , Proteínas Oncogénicas de Retroviridae/fisiología , Fracciones Subcelulares/metabolismo , Transactivadores/biosíntesis , Transactivadores/química , Transactivadores/fisiología , Activación Transcripcional/efectos de los fármacos
9.
Matrix Biol ; 34: 96-104, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24080228

RESUMEN

The growth hormone/insulin-like growth factor-I (GH/IGF-I) axis is an important stimulator of collagen synthesis in connective tissue, but the effect of chronically altered GH/IGF-I levels on connective tissue of the muscle-tendon unit is not known. We studied three groups of mice; 1) giant transgenic mice that expressed bovine GH (bGH) and had high circulating levels of GH and IGF-I, 2) dwarf mice with a disrupted GH receptor gene (GHR-/-) leading to GH resistance and low circulating IGF-I, and 3) a wild-type control group (CTRL). We measured the ultra-structure, collagen content and mRNA expression (targets: GAPDH, RPLP0, IGF-IEa, IGF-IR, COL1A1, COL3A1, TGF-ß1, TGF-ß2, TGF-ß3, versican, scleraxis, tenascin C, fibronectin, fibromodulin, decorin) in the Achilles tendon, and the mRNA expression was also measured in calf muscle (same targets as tendon plus IGF-IEb, IGF-IEc). We found that GHR-/- mice had significantly lower collagen fibril volume fraction in Achilles tendon, as well as decreased mRNA expression of IGF-I isoforms and collagen types I and III in muscle compared to CTRL. In contrast, the mRNA expression of IGF-I isoforms and collagens in bGH mice was generally high in both tendon and muscle compared to CTRL. Mean collagen fibril diameter was significantly decreased with both high and low GH/IGF-I signaling, but the GHR-/- mouse tendons were most severely affected with a total loss of the normal bimodal diameter distribution. In conclusion, chronic manipulation of the GH/IGF-I axis influenced both morphology and mRNA levels of selected genes in the muscle-tendon unit of mice. Whereas only moderate structural changes were observed with up-regulation of GH/IGF-I axis, disruption of the GH receptor had pronounced effects upon tendon ultra-structure.


Asunto(s)
Colágeno Tipo I/biosíntesis , Hormona del Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/genética , Músculo Esquelético/metabolismo , Animales , Bovinos , Tejido Conectivo/metabolismo , Tejido Conectivo/ultraestructura , Hormona del Crecimiento/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ratones , Ratones Transgénicos , Músculo Esquelético/ultraestructura , Biosíntesis de Proteínas , ARN Mensajero/biosíntesis , Tendones/metabolismo
10.
J Phys Condens Matter ; 23(33): 334206, 2011 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-21813964

RESUMEN

Nanoparticulate WO(3) films were prepared using microwave plasma synthesis and studied with respect to the electrical conductivity in dependence of ambient conditions. The WO(3) films with a monoclinic structure were made from cluster-assembled nanoparticles (diameter 3 nm) by means of dispersion and spin-coating. Above 100 °C a thermally activated decrease of the electrical resistance due to oxygen vacancy donors is found. A reversible increase of the electrical resistance R due to oxygen uptake is observed. The decrease of R in response to reducing H(2)S in the ppm range is studied in dependence of temperature and pre-annealing conditions.


Asunto(s)
Nanopartículas del Metal/química , Microondas , Nanoestructuras/química , Óxidos/química , Tungsteno/química , Conductividad Eléctrica , Ensayo de Materiales , Microscopía Electrónica de Transmisión , Nanoestructuras/ultraestructura , Propiedades de Superficie
11.
Rev Sci Instrum ; 81(5): 056107, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20515184

RESUMEN

In Kelvin probe force microscopy (KPFM) proper interpretation of the data is often difficult because the measured surface potential is affected by the interaction of the cantilever with the sample. In this work, the tip's interaction with a modeled surface potential distribution was simulated, leading to a calculated KPFM image. Although simplified, the calculation is capable of showing the influence of the cantilever in the correct qualitative manner, proven by a comparison with experimental data. Additionally, a deconvolution was performed on the simulated image, showing that for simple geometries revealing the "real" surface potential data is possible in principle.

14.
Phys Rev Lett ; 100(5): 057401, 2008 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-18352425

RESUMEN

Stark spectroscopy, which is well established for probing transitions between the ground and excited states of many material classes, is extended to transitions between transient excited states. To this end, it is combined with femtosecond pump-probe spectroscopy on a conjugated polymer with appropriately introduced traps which harvest excitation energy and build up a sufficient excited state population. The results indicate a significant difference in the effective dipole moments between two short lived excited states.

15.
Infect Disord Drug Targets ; 8(1): 31-45, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18473905

RESUMEN

Technology surrounding genomics, or the study of an organism's genome and its gene use, has advanced rapidly resulting in an abundance of readily available genomic data. Although genomics is extremely valuable, proteins are ultimately responsible for controlling most aspects of cellular function. The field of proteomics, or the study of the full array of proteins produced by an organism, has become the premier arena for the identification and characterization of proteins. Yet the task of characterizing a proteomic profile is more complex, in part because many unique proteins can be produced by the same gene product and because proteins have more diverse chemical structures making sequencing and identification more difficult. Proteomic profiles of a particular organism, tissue or cell are influenced by a variety of environmental stimuli, including those brought on by infectious disease. The intent of this review is to highlight applications of proteomics used in the study of pathogenesis, etiology and pathology of infectious disorders. While many infectious agents have been the target of proteomic studies, this review will focus on those infectious diseases which rank among the highest in worldwide mortalities, such as HIV/AIDS, tuberculosis, malaria, measles, and hepatitis.


Asunto(s)
Enfermedades Transmisibles/fisiopatología , Proteómica/métodos , Animales , Antiinfecciosos/farmacología , Enfermedades Transmisibles/tratamiento farmacológico , Enfermedades Transmisibles/etiología , Sistemas de Liberación de Medicamentos , Genómica/métodos , Humanos
16.
Radiologe ; 28(5): 204-8, 1988 May.
Artículo en Alemán | MEDLINE | ID: mdl-3393639

RESUMEN

Implementation of the radiological information system SIMEDOS in the central department of diagnostic radiology in the Marburg University Hospital is discussed. Special attention is given to the clinical and organizational problems of the department, as well as the planning and preparation phases of system implementation. This system has been in use for 10 months and our experience concerning problem-solving and the various user groups is described.


Asunto(s)
Departamentos de Hospitales/organización & administración , Sistemas de Información en Hospital , Servicio de Radiología en Hospital/organización & administración , Sistemas de Información Radiológica , Alemania Occidental , Humanos
17.
Phys Rev Lett ; 89(16): 167401, 2002 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-12398753

RESUMEN

Electrically induced phosphorescence from a poly(para-phenylene) ladder-type polymer is observed for the first time and characterized using time resolved spectroscopy. Short-lived phosphorescence is also observed in gated fluorescence spectra and is found to be quenched reversibly by oxygen. Thermally activated triplet diffusion to covalently bound palladium sites, which are formed at a concentration of about 80 ppm in a side reaction during polymer synthesis, is believed to be the cause of this novel effect, which suggests a new approach to the design of efficient electroluminescent materials.

18.
J Am Chem Soc ; 123(5): 946-53, 2001 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-11456629

RESUMEN

A polyfluorene 12 has been prepared in which bulky polyphenylene dendrimer substituents suppress formation of long wavelength emitting aggregates, thus giving a polymer with pure blue emission. Absorption- and emission spectra and molecular modeling confirm that the bulky dendrimer side chains do not cause extra torsion between the fluorene units. New polyfluorenes with 9,9-diaryl substituents have been prepared to determine the minimum size of substituent necessary for aggregation suppression. An LED using 12 has been demonstrated to produce blue emission with onset voltages below 4 V.

19.
Environ Sci Technol ; 18(4): 242-7, 1984 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22263762
20.
Environ Sci Technol ; 18(4): 248-53, 1984 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22263763
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