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1.
2.
Genet Mol Res ; 15(3)2016 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-27706635

RESUMEN

We investigated the relationship between miR-146a and miR-196a2 genetic polymorphisms and development of ovarian cancer in a Chinese population. A total of 134 patients and 227 control subjects were involved in our study between January 2012 and October 2014 from China-Japan Union Hospital of Jilin University. Genotyping of miR-146a and miR-196a2 was accomplished by polymerase chain reaction coupled with restriction fragment length polymorphism analysis. Unconditional multiple-logistic regression analysis indicated that the GG genotype of miR-146a was associated with an increased risk of ovarian cancer when compared to the CC genotype, and the adjusted OR (95%CI) was 3.73 (1.79-7.80). Moreover, the CG+GG genotype of miR-146a was associated with an increased risk of ovarian cancer compared with the CC genotype (OR = 1.68, 95%CI = 1.06-2.66), and the GG genotype had a higher risk of ovarian cancer than the CC+CG genotype (OR = 3.02, 95%CI = 1.55-5.98). In conclusion, our study suggests that the miR-146a polymorphism is associated with increased risk of ovarian cancer and could be used as a biomarker for ovarian cancer susceptibility.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , MicroARNs/genética , Neoplasias Ováricas/genética , Polimorfismo de Nucleótido Simple , Pueblo Asiatico , Femenino , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/etnología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Riesgo
5.
J Virol Methods ; 98(1): 53-61, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11543884

RESUMEN

Human parainfluenza virus types 1 (hPIV-1), 2, and 3 represent significant respiratory pathogens for which no antiviral treatment is currently available. To characterize the biochemical functions of the hPIV-1 hemagglutinin-neuraminidase (HN) glycoprotein, a potential target for antiviral therapy, we cloned and expressed a soluble portion of hPIV-1 HN (amino acid residues 137-575), lacking the N-terminal hydrophobic membrane anchorage region, in insect cells using the baculovirus secretion expression system. The expressed HN protein was purified through cation-exchange chromatography followed by metal affinity chromatography, using the 6xHis epitope introduced at the carboxyl terminus of the recombinant protein. N-terminal amino acid sequence analysis of purified HN indicated that the honeybee melittin secretion signal peptide was correctly removed during post-translational processing. Further characterization revealed that the purified HN protein was N-glycosylated and exhibited neuraminidase activity whose characteristics resembled those of the native HN protein of hPIV-1 virions. The establishment of this expression and purification system has allowed us to further explore the biochemical characteristics of paramyxovirus HN and to obtain material that could be suitable for X-ray crystallography studies.


Asunto(s)
Proteína HN/biosíntesis , Virus de la Parainfluenza 1 Humana/metabolismo , Secuencia de Aminoácidos , Animales , Baculoviridae/genética , Línea Celular , Vectores Genéticos , Proteína HN/química , Proteína HN/genética , Humanos , Concentración de Iones de Hidrógeno , Insectos , Datos de Secuencia Molecular , Neuraminidasa/metabolismo , Níquel , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Cloruro de Sodio
6.
Mol Psychiatry ; 3(1): 32-7, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9491810

RESUMEN

Many human hereditary neurodegenerative diseases are caused by expanded CAG repeats, and anonymous CAG expansions have also been described in schizophrenia and bipolar disorder. We have isolated and sequenced a novel human cDNA encoding a neuronal, small conductance calcium-activated potassium channel (hSKCa3) that contains two arrays of CAG trinucleotide repeats. The second CAG repeat in hSKCa3 is highly polymorphic in control individuals, with alleles ranging in size from 12 to 28 repeats. The overall allele frequency distribution is significantly different in patients with schizophrenia compared to ethnically matched controls (Wilcoxon Rank Sum test, P=0.024), with CAG repeats longer than the modal value being over-represented in patients (Fisher Exact test, P=0.0035). A similar, non-significant, trend is seen for patients with bipolar disorder. These results provide evidence for a possible association between longer alleles in the hSKCa3 gene and both of these neuropsychiatric diseases, and emphasize the need for more extensive studies of this new gene. Small conductance calcium-activated K+ channels play a critical role in determining the firing pattern of neurons. These polyglutamine repeats may modulate hSKCa3 channel function and neuronal excitability, and thereby increase disease risk when combined with other genetic and environmental effects.


Asunto(s)
Trastorno Bipolar/genética , Neuropéptidos/genética , Polimorfismo Genético , Canales de Potasio/genética , Esquizofrenia/genética , Repeticiones de Trinucleótidos , Alelos , Secuencia de Aminoácidos , Encéfalo/metabolismo , Humanos , Datos de Secuencia Molecular , Neuronas/metabolismo , Neuropéptidos/biosíntesis , Neuropéptidos/química , Canales de Potasio/biosíntesis , Canales de Potasio/química , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Canales de Potasio de Pequeña Conductancia Activados por el Calcio
7.
Gastroenterology ; 106(6): 1542-7, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8194700

RESUMEN

BACKGROUND/AIMS: Familial adenomatous polyposis is caused by germline mutation of the adenomatous polyposis coli (APC) gene. Affected individuals develop hundreds of colorectal adenomas at young age and can have extracolonic lesions. METHODS: This study evaluated the phenotype of 74 patients with familial adenomatous polyposis from 11 unrelated families with an identical 5-base pair deletion at codon 1309 of the APC gene. RESULTS: Polyp density in the sigmoid colon of 16 patients from 9 families varied from 3.8 to 13.1/cm2, and mean polyp diameter ranged from 1.4 +/- 0.1 to 2.7 +/- 0.1 mm. The distribution of colonic adenomas also varied, with diffuse polyposis in 6 patients but relative polyp sparing in the more proximal colon in 6 others. Age at diagnosis of colorectal cancer ranged from 19 to 62 years, but the mean age did not differ among the 4 families with multiple cases. Colorectal cancers occurred predominantly in the rectosigmoid (80%) but also in the more proximal colon. The percentage of patients affected by various extracolonic lesions differed widely among and within the 11 families (range, 0%-100%). CONCLUSIONS: APC gene mutation at codon 1309 results in intrafamily and interfamily phenotypic variation in familial adenomatous polyposis. Environmental and/or other genetic factors must play roles in the expression of germline APC gene mutations.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Mutación , Poliposis Adenomatosa del Colon/patología , Adulto , Codón , Colon/patología , Neoplasias Colorrectales/patología , Femenino , Eliminación de Gen , Humanos , Masculino , Persona de Mediana Edad , Fenotipo
8.
J Comp Neurol ; 314(3): 512-25, 1991 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1726108

RESUMEN

Previous transneuronal anterograde tracing studies have shown that the retino-thalamic pathway to the posteromedial lateral suprasylvian (PMLS) visual area of cortex is heavier than normal in adult cats that received neonatal damage to visual cortical areas 17, 18, and 19. In contrast, the strength of this projection does not appear to differ from that in normal animals in cats that experienced visual cortex damage as adults. In the present study, we used retrograde tracing methods to identify the thalamic cells that project to the PMLS cortex in adult cats that had received a lesion of visual cortex during infancy or adulthood. In five kittens, a unilateral visual cortex lesion was made on the day of birth, and horseradish peroxidase (HRP) was injected into the PMLS cortex of both hemispheres when the animals were 10.5 to 13 months old. For comparison, HRP was injected bilaterally into the PMLS cortex of three cats 6.5 to 13.5 months after they received a similar unilateral visual cortex lesion as adults. In cats with a neonatal lesion, retrograde labeling was found in the large neurons that survive in the otherwise degenerated layers A and A1 of the lateral geniculate nucleus (LGN) ipsilateral to the lesion. Retrograde labeling of A-layer neurons was not seen in the undamaged hemisphere of these animals or in either hemisphere of animals that had received a lesion as adults. As in normal adult cats, retrograde labeling also was present in the C layers of the LGN, the medial interlaminar nucleus, the posterior nucleus of Rioch, the lateral posterior nucleus, and the pulvinar nucleus ipsilateral to a neonatal or adult lesion. Quantitative estimates indicate that the number of labeled cells is much larger than normal in the C layers of the LGN ipsilateral to a neonatal visual cortex lesion. Thus the results indicate that the heavier than normal projection from the thalamus to PMLS cortex that exists in adult cats after neonatal visual cortex damage arises, at least in part, from surviving LGN neurons in the A and C layers of the LGN. Although several thalamic nuclei, as well as the C layers of the LGN, continue to project to PMLS cortex after an adult visual cortex lesion, these projections appear not to be affected significantly by the lesion.


Asunto(s)
Gatos/anatomía & histología , Neuronas/citología , Tálamo/anatomía & histología , Corteza Visual/anatomía & histología , Corteza Visual/fisiología , Envejecimiento , Animales , Animales Recién Nacidos , Transporte Axonal , Peroxidasa de Rábano Silvestre , Neuronas/fisiología , Tálamo/fisiología , Corteza Visual/crecimiento & desarrollo
9.
J Comp Neurol ; 314(3): 526-33, 1991 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1726109

RESUMEN

In the study reported in the preceding paper, we used retrograde labeling methods to show that the enhanced projection from the thalamus to the posteromedial lateral suprasylvian (PMLS) visual area of cortex that is present in adult cats following neonatal visual cortex damage arises at least partly from surviving neurons in the dorsal lateral geniculate nucleus (LGN). In the C layers of the LGN, many more cells than normal are retrogradely labeled by horseradish peroxidase (HRP) injected into PMLS cortex ipsilateral to a visual cortex lesion. In addition, retrogradely labeled cells are found in the A layers, which normally have no projection to PMLS cortex in adult cats. The purpose of the present study was to investigate the mechanisms of this enhanced projection by examining the normal development of projections from the thalamus, especially the LGN, to PMLS cortex. Injections of HRP were made into PMLS cortex on the day of birth or at 1, 2, 4, or 8 weeks of age. Retrogradely labeled neurons were present in the lateral posterior nucleus, posterior nucleus of Rioch, pulvinar, and medial interlaminar nucleus, as well as in the LGN, at all ages studied. Within the LGN of the youngest kittens, a small number of retrogradely labeled cells was present in the interlaminar zones and among the cells in the A layers that border these zones. Such labeled cells were virtually absent by 8 weeks of age, and they are not found in normal adult cats. Sparse retrograde labeling of C-layer neurons also was present in newborn kittens.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Gatos/crecimiento & desarrollo , Cuerpos Geniculados/crecimiento & desarrollo , Corteza Visual/crecimiento & desarrollo , Vías Visuales/crecimiento & desarrollo , Envejecimiento , Animales , Transporte Axonal , Cuerpos Geniculados/anatomía & histología , Cuerpos Geniculados/citología , Peroxidasa de Rábano Silvestre , Neuronas/citología , Corteza Visual/anatomía & histología , Corteza Visual/citología , Vías Visuales/anatomía & histología , Vías Visuales/citología
10.
Atherosclerosis ; 88(1): 1-14, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1878005

RESUMEN

In this study, the fluorescent morphological structures in normal coronary artery, normal aorta, and atherosclerotic aorta were histochemically identified and spectroscopically characterized in situ using ultraviolet-excited microspectrofluorimetry. Excitation wavelengths of 290 nm and 310/312 nm were employed to observe two distinct fluorescence bands, with peak emission wavelengths near 335 nm and 380 nm, respectively. Emission of the short wavelength 335 nm band, previously assigned to tryptophan residues in tryptophan-containing proteins, was observed from all the morphological structures in the vessel walls and was isolated in groups of smooth muscle cells in aorta and coronary artery media. The long wavelength 380 nm band was assigned to distinct fluorophores associated with the structural proteins collagen and elastin and was observed in collagen fibers and elastic fibers, respectively. The corresponding morphological structures in normal aorta, normal coronary artery, and atherosclerotic aorta exhibited similar fluorescence lineshapes. In atherosclerotic plaque, a distinct fluorescence band, peaking near 370 nm, was observed in the emission from both ceroid granules and necrotic core. Using a simple, quantitative model, differing contributions of collagen, elastin, and tryptophan-containing protein fluorescence were shown to account for over 95% of the emission from the intima, media, and adventitia layers of non-necrotic aorta and coronary artery.


Asunto(s)
Arterias/citología , Aorta/metabolismo , Aorta/patología , Arterias/metabolismo , Arterias/patología , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Calcinosis/metabolismo , Calcinosis/patología , Vasos Coronarios/metabolismo , Vasos Coronarios/patología , Humanos , Rayos Láser , Microscopía Fluorescente , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Espectrometría de Fluorescencia
11.
IEEE Trans Biomed Eng ; 36(12): 1222-32, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2606498

RESUMEN

This paper describes a general model of tissue fluorescence which can be used both to: 1) determine chemical and physical properties of the tissue, and 2) design an optimal algorithm for clinical diagnosis of tissue composition. This model is based on a picture of tissue as a single, optically thick layer, in which fluorophores and absorbing species are homogeneously distributed. As a specific example, the model is applied to the laser induced fluorescence (LIF) of normal and atherosclerotic human aorta using 476 nm excitation. Methods for determining the relevant attenuation and fluorescence lineshapes are detailed, and these lineshapes are used to apply the model to data from 148 samples. The model parameters are related to the concentrations of the major arterial chromophores: structural proteins, hemoglobin and ceroid. In addition, the model parameters are used to derive diagnostic algorithms for the presence of atherosclerosis. Utilizing a binary classification scheme, the presence or absence of pathology was determined correctly in 88 percent of cases.


Asunto(s)
Arteriosclerosis/patología , Rayos Láser , Microscopía Fluorescente/métodos , Algoritmos , Aorta/patología , Colágeno/análisis , Elastina/análisis , Humanos
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