Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Indian Pediatr ; 58(8): 709-717, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-34465657

RESUMEN

OBJECTIVE: To estimate the disease and economic burden of pertussis amongst hospitalised infants in India. DESIGN: Multicentric hospital-based surveillance study. PARTICIPANTS: Hospitalised infants with clinical suspicion of pertussis based on predefined criteria. OUTCOME MEASURES: Proportion of infants with laboratory-confirmed pertussis, economic burden of pertussis amongst hospitalised infants. RESULTS: 693 clinically suspected infants were recruited of which 32 (4.62%) infants had laboratory-confirmed pertussis. Progressive cough with post-tussive emesis (50%) and pneumonia (34%) were the common clinical presentations; apnea in young infants was significantly associated with pertussis. Infants with pertussis were more likely to be younger (median age 102.5 days vs.157 days) and born preterm (42.9% vs 24.5%). Almost 30% infants with pertussis had not received vaccine for pertussis with 50% of these infants aged less than 2 months. Pertussis was associated with higher costs of hospitalisation, pharmacy and loss of working days by caregivers as compared to non-pertussis cases. CONCLUSIONS: Younger infants, those born preterm and those inadequately immunised against pertussis are at higher risk of pertussis infection. Timely childhood immunisation and introduction of maternal immunisation for pertussis can help in reducing the disease burden.


Asunto(s)
Tos Ferina , Anciano de 80 o más Años , Niño , Hospitalización , Hospitales , Humanos , Lactante , Recién Nacido , Vacuna contra la Tos Ferina , Atención Terciaria de Salud , Vacunación , Tos Ferina/diagnóstico , Tos Ferina/epidemiología , Tos Ferina/prevención & control
2.
Angew Chem Int Ed Engl ; 60(39): 21242-21249, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34378296

RESUMEN

Mesoporous carbon nitrides with C3 N5 and C3 N6 stoichiometries created a new momentum in the field of organic metal-free semiconductors owing to their unique band structures and high basicity. Here, we report on the preparation of a novel graphitic microporous carbon nitride with a tetrazine based chemical structure and the composition of C3 N5.4 using ultra-stable Y zeolite as the template and aminoguanidine hydrochloride, a high nitrogen-containing molecule, as the CN precursor. Spectroscopic characterization and density functional theory calculations reveal that the prepared material exhibits a new molecular structure, which comprises two tetrazines and one triazine rings in the unit cell and is thermodynamically stable. The resultant carbon nitride shows an outstanding surface area of 130.4 m2 g-1 and demonstrates excellent CO2 adsorption per unit surface area of 47.54 µmol m-2 , which is due to the existence of abundant free NH2 groups, basic sites and microporosity. The material also exhibits highly selective sensing over water molecules (151.1 mmol g-1 ) and aliphatic hydrocarbons due to its unique microporous structure with a high amount of hydrophilic nitrogen moieties and recognizing ability towards small molecules.

3.
RSC Adv ; 10(53): 32088-32101, 2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-35518145

RESUMEN

The work presented involves the generation of oxygen plasma species at low pressure utilizing an Electron Cyclotron Resonance (ECR) plasma reactor, and their interactions with micron- and nano-sized iron films (M-Fe and N-Fe film respectively) prepared using ethyl cellulose processed at high temperature. A specially designed radiation heater (RH) was used to raise the surface temperature of the film rapidly, exactly at the film interface, where the plasma species interact with the surface. As a result of the interaction of oxygen plasma species and temperature, iron is oxidized to different polymorphs depending on the operating pressure and hence oxygen gas flow rate. The phase, as well as the morphology of the film was controlled by monitoring the oxygen flow rate using the unique Plasma-Assisted Thermal Oxidation (PATO) process. Different polymorphs, viz., Fe3O4, γ-Fe2O3, α-Fe2O3 and different morphologies, such as polygonal, compact facets, wire-like (1D) nanostructures at the surface were obtained for the films processed using PATO. The selected PATO-processed films were investigated for Field Electron Emission (FEE) properties. The 1D-grown surface of iron oxide obtained from the M-Fe film showed a turn-on field of 3 MV m-1 and emission current of 337 µA cm-2, whereas the pyramidal surface morphology obtained using N-Fe film gives a turn-on field of 3.3 MV m-1 with an emission current of 578 µA cm-2.

4.
Nanoscale ; 11(21): 10292-10305, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31099377

RESUMEN

The thermal and moisture instabilities of pure organic lead halide perovskites are the foremost concerns towards the commercialization of perovskite solar cells, which can be avoided by introducing an inorganic cation, such as cesium ion (Cs+) at the A-site of the perovskite crystals. In this report, the impacts of substituted Cs+ cations on the inherent properties such as microstructures, morphology, and photophysics of pure methylammonium lead bromide (MAPbBr3) perovskites have been investigated. Successful formation of mixed MA1-xCsxPbBr3 phases (with 0 ≤ x ≤ 1.0) was predicted from the theoretically calculated tolerance factor, which was further supported by the appearance of sharp diffraction peaks in X-ray diffraction (XRD) patterns without any additional peaks in the whole composition range. Substitution of Cs+ ions brings significant lattice contraction in the parent MAPbBr3 crystal due to the ion size disparity in the ionic radii between MA+ and Cs+ ions. We examine the vibrational signatures of the Raman bands related to the organic MA+ and infer the nature of interactions between the organic moiety and the surrounding inorganic cage as a function of Cs concentration. Raman spectroscopic analysis reveals structural distortion due to the altered H-bonding interaction of the N+-HBr- type between MA+ and the PbBr3- octahedral framework as a function of Cs content, which is responsible for the octahedral tilting in Cs substituted MAPbBr3. We also found hindered rotational motions of MA+ in the octahedral cage of mixed cationic systems, resulting in the orientational ordering of MA in the presence of Cs. These results certainly offer highly ordered mixed phase structures and promote superior thermal stability, as evident from the thermogravimetric analysis. The photoluminescence intensity becomes considerably enhanced at increased substitution levels, which highlights the capability of incorporated Cs+ cations in suppressing non-radiative recombination in a pure MA-based crystal, possibly related to the mitigation of trapping. The substitution of Cs+ with MAPbBr3 allows innovative strategies to improve the proficiency of tandem solar cells by modifying their structural and photophysical properties.

5.
Eur J Pharm Sci ; 82: 115-25, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26616823

RESUMEN

Conformational and molecular docking analysis of 2-acetylamino-5-bromo-6-methylpyridine molecule was carried out and the vibrational spectral analysis was also carried out using experimental and theoretical methods. The calculated and experimentally observed vibrational frequencies of the molecule were assigned and compared. The pyridine ring CH stretching and CH3 stretching vibrational modes were shifted towards higher wavenumber (blue shift). The C=O stretching vibrational frequency was shifted towards lower wavenumber (red shift). Ultraviolet-visible spectrum of the molecule simulated theoretically was further validated experimentally. Molecular reactivity and stability were investigated using the frontier molecular orbital analysis and the related quantum chemical molecular properties. Natural bond orbital analysis and the structure activity relations were also studied to confirm the bioactivity of the molecule. Anticancer activity was examined based on molecular docking analysis and it has been identified that the AABMP molecule can act as a good inhibitor against lung cancer.


Asunto(s)
Acetamidas/química , Aminopiridinas/química , Antineoplásicos/química , Proteínas de Neoplasias/química , Simulación del Acoplamiento Molecular , Análisis Espectral/métodos , Vibración
7.
J Neuroinflammation ; 12: 135, 2015 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-26198819

RESUMEN

BACKGROUND: Intracranial aneurysm (IA) is often asymptomatic until the time of rupture resulting in subarachnoid hemorrhage (SAH).There is no precise biochemical or phenotype marker for diagnosis of aneurysm. Environmental risk factors that associate with IA can result in modifying the effect of inherited genetic factors and thereby increase the susceptibility to SAH. In addition subsequent to aneurismal rupture, the nature and quantum of inflammatory response might be critical for repair. Therefore, genetic liability to inflammatory response caused by polymorphisms in cytokine genes might be the common denominator for gene and environment in the development of aneurysm and complications associated with rupture. METHODS: Functionally relevant polymorphisms in the pro- and anti-inflammatory cytokine genes IL-1 complex (IL1A, IL1B, and IL1RN), TNFA, IFNG, IL3, IL6, IL12B, IL1RN, TGFB1, IL4, and IL10] were screened in radiologically confirmed 220 IA patients and 250 controls from genetically stratified Malayalam-speaking Dravidian ethnic population of south India. Subgroup analyses with genetic and environmental variables were also carried out. RESULTS: Pro-inflammatory cytokines TNFA rs361525, IFNG rs2069718, and anti-inflammatory cytokine IL10 rs1800871 and rs1800872 were found to be significantly associated with IA, independent of epidemiological factors. TGFB1 rs1800469 polymorphism was observed to be associated with IA through co-modifying factors such as hypertension and gender. Functional prediction of all the associated SNPs of TNFA, IL10, and TGFB1 indicates their potential role in transcriptional regulation. Meta-analysis further reiterates that IL1 gene cluster and IL6 were not associated with IA. CONCLUSIONS: The study suggests that chronic exposure to inflammatory response mediated by genetic variants in pro-inflammatory cytokines TNFA and IFNG could be a primary event, while stochastic regulation of IL10 and TGFB1 response mediated by comorbid factors such as hypertension may augment the pathogenesis of IA through vascular matrix degradation. The implication and interaction of these genetic variants under a specific environmental background will help us identify the resultant phenotypic variation in the pathogenesis of intracranial aneurysm. Identifying genetic risk factors for inflammation might also help in understanding and addressing the posttraumatic complications following the aneurismal rupture.


Asunto(s)
Interferón gamma/genética , Interleucina-10/genética , Aneurisma Intracraneal/genética , Procesos Estocásticos , Factor de Crecimiento Transformador beta1/genética , Factor de Necrosis Tumoral alfa/genética , Adulto , Estudios de Casos y Controles , Comorbilidad , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Hipertensión/genética , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales , Fumar , Hemorragia Subaracnoidea/genética
8.
Opt Lett ; 40(4): 491-4, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25680132

RESUMEN

Single crystals of lithium niobate (LiNbO3), possessing high birefringence and anisotropic properties have been explored, for a long time, to harness their excellent electro-optic properties. However, their nanoforms are comparatively less explored. In this context, dielectric constant and polarization (P) versus electric-field (E) characteristics of LiNbO3 nanomaterials have been studied. A nonideal P-E loop and a dielectric constant of 20 at the onset of 1 kHz were seen. The electro-optic sensitivity was found to be 4 times as compared to the bulk LiNbO3 crystals. The results are attributed to oxygen vacancies, antisite defects, and grain boundary effects in an already congruent structural matrix of LiNbO3.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 252-63, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25498822

RESUMEN

The vibrational spectra of 2-amino-7-bromo-5-oxo-[1]benzopyrano [2,3-b]pyridine-3 carbonitrile were recorded using fourier transform-infrared and fourier transform-Raman spectrometer. The optimized structural parameters, vibrational frequencies, Mulliken atomic charge distribution, frontier molecular orbitals, thermodynamic properties, temperature dependence of thermodynamic parameters, first order hyperpolarizability and natural bond orbital calculations of the molecule were performed using the Gaussian 09 program. The vibrational frequencies were assigned on the basis of potential energy distribution calculation using the VEDA 4.0 program. The calculated first order hyperpolarizability of ABOBPC molecule was obtained as 6.908×10(-30) issue, which was 10.5 times greater than urea. The nonlinear optical activity of the molecule was also confirmed by the frontier molecular orbitals and natural bond orbital analysis. The frontier molecular orbitals analysis shows that the lower energy gap of the molecule, which leads to the higher value of first order hyperpolarizability. The natural bond orbital analysis indicates that the nonlinear optical activity of the molecule arises due to the π→π(∗) transitions. The Mulliken atomic charge distribution confirms the presence of intramolecular charge transfer within the molecule. The reactive site of the molecule was predicted from the molecular electrostatic potential contour map. The values of thermo dynamic parameters were increasing with increasing temperature.


Asunto(s)
Benzopiranos/química , Nitrilos/química , Piridinas/química , Espectrometría Raman , Modelos Moleculares , Conformación Molecular , Distribución Normal , Óptica y Fotónica , Teoría Cuántica , Programas Informáticos , Espectrofotometría Infrarroja , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Temperatura , Termodinámica , Vibración
11.
Artículo en Inglés | MEDLINE | ID: mdl-24727165

RESUMEN

The molecular structure of 2-(tert-butoxycarbonyl (Boc) -amino)-5-bromopyridine (BABP) was optimized by the DFT/B3LYP method with 6-311G (d,p), 6-311++G (d,p) and cc-pVTZ basis sets using the Gaussian 09 program. The most stable optimized structure of the molecule was predicted by the DFT/B3LYP method with cc-pVTZ basis set. The vibrational frequencies, Mulliken atomic charge distribution, frontier molecular orbitals and thermodynamical parameters were calculated. These calculations were done at the ground state energy level of BABP without applying any constraint on the potential energy surface. The vibrational spectra were experimentally recorded using Fourier Transform-Infrared (FT-IR) and micro-Raman spectrometer. The computed vibrational frequencies were scaled by scale factors to yield a good agreement with observed experimental vibrational frequencies. The complete theoretically calculated and experimentally observed vibrational frequencies were assigned on the basis of Potential Energy Distribution (PED) calculation using the VEDA 4.0 program. The vibrational modes assignments were performed by using the animation option of GaussView 05 graphical interface for Gaussian program. The Mulliken atomic charge distribution was calculated for BABP molecule. The molecular reactivity and stability of BABP were also studied by frontier molecular orbitals (FMOs) analysis.


Asunto(s)
4-Aminopiridina/análogos & derivados , 4-Aminopiridina/química , Modelos Moleculares , Conformación Molecular , Teoría Cuántica , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman
12.
Meta Gene ; 2: 651-60, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25606449

RESUMEN

Intracranial aneurysm (IA) accounts for 85% of Subarachnoid Hemorrhage (SAH) and is mainly caused due to the weakening of arterial wall. The structural integrity of the intracranial arteries is mainly influenced by the extracellular matrix (ECM) remodeling. The Proteoglycan Versican plays an important role in extracellular matrix assembly and plays a major role in the pathogenesis of IA. The linkage studies also indicated VCAN as a putative candidate gene for IA in the 5q22-31 region. Using a case-control study design, we tested the hypothesis whether the variants in VCAN gene, nonsynonymous variants in the coding region of Glycosaminoglycan α (GAG-α) and GAG-ß and two reported SNPs involved in splicing rs251124 and rs173686 can increase the risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. We selected 200 radiologically confirmed aneurysmal cases and 250 ethnically, age and sex matched controls from the Dravidian Malayalam speaking population of South India. The present study reiterated the earlier association of rs251124 with intracranial aneurysm (P = 0.0002) and also found a novel association with rs2287926 (G428D) in exon 7 coding for GAG-α with intracranial aneurysm (P = 0.0015). Interestingly, both these SNPs contributed to higher risk for aneurysm in males. In-silico analysis predicted this SNP to have the highest functional relevance in the gene which might have a potentially altered regulatory role in transcription and splicing. Using meta-analysis with available literature rs251124 was found to be the strongest intracranial aneurysm marker for global ethnicities. This study with a novel functional SNP rs2287926 (G428D) further substantiates the potential role of VCAN in the pathogenesis of IA.

14.
Mol Biol Rep ; 40(10): 5869-74, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24065528

RESUMEN

Intracranial aneurysm (IA) accounts for 85 % of haemorrhagic stroke and is mainly caused due to weakening of arterial wall. Lysyl oxidase (LOX) is a cuproenzyme involved in cross linking structural proteins collagen and elastin, thus providing structural stability to artery. Using a case-control study design, we tested the hypothesis whether the variants in LOX gene flanking the two LD block, can increase risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. SNPs were genotyped by fluorescence-based competitive allele-specific PCR (KASPar) chemistry. We selected 200 radiologically confirmed aneurysmal cases and 235 ethnically and age and gender matched controls from the Dravidian Malayalam speaking population of South India. We observed marked interethnic differences in the genotype distribution of LOX variants when compared to Japanese and African populations. However, there was no significant association with any of the LOX variants with IA. This study also could not observe any significant role of LOX polymorphisms in influencing IA either directly or indirectly through its confounding factors such as hypertension and gender in South Indian population.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Aneurisma Intracraneal/enzimología , Aneurisma Intracraneal/genética , Polimorfismo de Nucleótido Simple/genética , Proteína-Lisina 6-Oxidasa/genética , Estudios de Casos y Controles , Demografía , Femenino , Frecuencia de los Genes/genética , Humanos , India , Desequilibrio de Ligamiento/genética , Masculino , Persona de Mediana Edad
16.
J Indian Soc Pedod Prev Dent ; 29(6 Suppl 2): S70-3, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22169842

RESUMEN

The presence of nasal air leak in cleft palate patients with velopharyngeal incompetence leads to characteristic nasal snort. The efficacy of the palatal lift appliance in patients with adequate velopharyngeal tissue with incompetence was tested. Speech quality improved after the wearing of palatal lift appliance. Palatal lift appliances are simple and efficient in reducing the nasal air leak. Ongoing speech therapy is necessary and advised for patients receiving palatal lift.


Asunto(s)
Prótesis e Implantes , Diseño de Prótesis/métodos , Insuficiencia Velofaríngea/terapia , Trastornos de la Articulación/terapia , Niño , Femenino , Humanos , Paladar Blando/fisiopatología , Trastornos de la Voz/terapia
17.
Cerebrovasc Dis ; 29(3): 268-74, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20090318

RESUMEN

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) has a mortality rate as high as 50%. The prevalence of intracranial aneurysms from various parts of India varies from 0.75 to 10.3%, with higher numbers of cases being diagnosed due to the increasing age of the population and improvements in imaging techniques. However, little is known about the attributable risk factors of aSAH in the Indian population. METHODS: Using a case-control study we estimated the risk of factors such as hypertension, cigarette smoking, alcohol consumption, diabetes mellitus and family history of aSAH in a South Indian population. The population-attributable risk (PAR) of smoking, hypertension and alcohol use was estimated for the South Indian as well as for the general Indian population. RESULTS: Our results showed that cigarette smoking (OR, 3.59; p < 0.001) and a history of hypertension (OR, 2.98; p < 0.001) were significant risk factors associated with aSAH. When patients were classified by gender, it was observed that being a smoker and having hypertension increased the risk for aSAH by nearly fourfold in men. Among women, hypertension and older age were significant risk factors. The PAR estimates indicated that smoking (OR, 3.59; 95% CI, 2.13-6.06) and hypertension (OR, 2.98; 95% CI, 1.73-5.12) are significant risk factors. CONCLUSIONS: Hypertension and smoking may be causal risk factors which might also modify the effect of genetic factors that could increase susceptibility to aSAH in the Indian population. Since these risk factors are amenable to effective modification, our findings will be useful for a gender-specific management of aSAH.


Asunto(s)
Hemorragia Subaracnoidea/etnología , Hemorragia Subaracnoidea/etiología , Adulto , Factores de Edad , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/etnología , Estudios de Casos y Controles , Diabetes Mellitus/etnología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/complicaciones , Hipertensión/etnología , India/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Linaje , Prevalencia , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos , Fumar/etnología
18.
Arch Neurol ; 57(2): 210-4, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10681079

RESUMEN

BACKGROUND: Angiotensin-converting enzyme has been reported to show altered activity in patients with neurologic diseases. An insertion-deletion polymorphism in ACE has recently been linked to heart disease, cerebrovascular disease, and AD. OBJECTIVE: To determine whether the angiotensin-converting enzyme (ACE) is associated with risk of Alzheimer disease (AD). METHODS: We investigated the ACE polymorphism as a potential risk factor for AD in 151 patients with AD and 206 ethnically matched controls from Russia and in 236 patients with AD and 169 controls from North America by means of allele association methods and logistic regression. RESULTS: None of the ACE genotypes was associated with increased susceptibility to AD in the total sample or in subsets stratified by apolipoprotein E gene (APOE) epsilon4 status. However, the D allele was more frequent among AD cases between ages 66 and 70 years compared with controls in both the Russian (P = .02) and North American (P = .001) datasets. In this age group, the effect of D (odds ratio, 11.2; 95% confidence interval, 2.9-44.0) appeared to be independent of and equal or greater in magnitude to the effect of APOE epsilon4 (odds ratio, 7.8; 95% confidence interval, 3.5-7.4). CONCLUSIONS: Our results suggest that APOE and ACE genotypes may be independent risk factors for late-onset AD, but the ACE association needs to be confirmed in independent samples in which the time and extent of vascular cofactors can be assessed.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Peptidil-Dipeptidasa A/metabolismo , Anciano , Alelos , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/genética , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , ADN/análisis , ADN/genética , Cartilla de ADN , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Moscú/epidemiología , Ontario/epidemiología , Peptidil-Dipeptidasa A/genética , Factores de Riesgo
19.
Genet Epidemiol ; 17 Suppl 1: S679-84, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10597513

RESUMEN

Knowing the answers, we used the GAW11 data set to compare the power and efficiency of discordant versus concordant affected sib pairs for qualitative traits at different levels of penetrance. Samples of 200 concordant sib pairs outperformed discordant sib pairs for low penetrance (40%) and 70% penetrance models while at 90% penetrance they performed equally well. Increasing the sample size of discordant sib pairs to twice that of concordant pairs was not enough to reach the power of concordant sib pairs at the 40% and 70% penetrance models. For low penetrance using a combination of concordant and discordant sib pairs resulted in higher power than using discordant sib pairs alone. At 90% penetrance, the power of concordant and discordant sib pairs was similar in the region close to the gene while concordant sib pairs performed better at locations further from the gene.


Asunto(s)
Ligamiento Genético , Penetrancia , Carácter Cuantitativo Heredable , Marcadores Genéticos , Pruebas Genéticas , Humanos , Escala de Lod , Modelos Genéticos , Núcleo Familiar , Recurrencia , Factores de Riesgo
20.
Genet Epidemiol ; 17 Suppl 1: S761-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10597527

RESUMEN

Linkage analysis was performed on the GAW11 Problem 2 data set using stratification to explore the effects of the environmental risk factors and the differences between mild and severe phenotypes. Analysis of the four study populations stratified by the two risk factors identified regions on chromosomes 3 and 5 with significant evidence for linkage. Other loci were sought by removing families consistent with linkage to the chromosome 3 locus. Our studies identified a locus on chromosome 3 (markers 43-46) associated with the mild phenotype in the presence of risk factor 1 and with the severe phenotype independent of risk factor 1. This suggests that distinct allelic variants at the chromosome 3 locus may cause different forms of disease. The locus identified on chromosome 5 (markers 36-39) was linked to the severe phenotype, but exposure to factor 1 or 2 may have a protective effect. The regions on chromosomes 3 and 5 appeared to have independent roles in disease etiology. Evidence for two loci on chromosome 1 linked to the mild form was found. The methods successfully identified linkages and interaction consistent with the generating model.


Asunto(s)
Ambiente , Genotipo , Modelos Genéticos , Ligamiento Genético , Marcadores Genéticos , Pruebas Genéticas , Genoma , Humanos , Herencia Multifactorial , Fenotipo , Tamaño de la Muestra , Programas Informáticos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA