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1.
J Dent Res ; 96(11): 1322-1329, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28662356

RESUMO

Prior genome-wide association studies for oral clefts have focused on clinic-based samples with unclear generalizability. Prior samples were also small for investigating effects by cleft type and exclusively studied isolated clefts (those occurring without other birth defects). We estimated the effects of 17 top loci on cleft types in both isolated and nonisolated cases in the largest consortium to date of European-descent population-based studies. Our analytic approach focused on a mother-child dyad case-control design, but it also allowed analyzing mother-only or child-only genotypes to maximize power. Our total sample included 1,875 cases with isolated clefts, 459 cases with nonisolated clefts, and 3,749 controls. After correcting for multiple testing, we observed significant associations between fetal single-nucleotide polymorphisms (SNPs) at IRF6, PAX7, 8q21.3, 8q24, KIAA1598-VAX1, and MAFB and isolated cleft lip only (CLO) and cleft lip and palate (CLP). Significant associations were observed between isolated CLO and fetal SNPs near TPM1 and NOG1 and between CLP and fetal SNPs at ABCA4-ARHGAP29, THADA, FOXE1, and SPRY2. Overall, effects were similar for isolated CLO and CLP, except for ABCA4-ARHGAP29. A protective effect was observed for the fetal NOG1 SNP on cleft palate only, opposite in direction to the effect on CLO. For most fetal SNPs, a dose-response allelic effect was observed. No evidence of parent-of-origin or maternal genome effects was observed. Overall, effect direction and magnitude were similar between isolated and nonisolated clefts, suggesting that several loci are modifiers of cleft risk in both isolated and nonisolated forms. Our results provide reliable estimates of the effects of top loci on risks of oral clefts in a population of European descent.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Loci Gênicos/genética , Alelos , Estudos de Casos e Controles , Fenda Labial/embriologia , Fissura Palatina/embriologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único , População Branca
2.
Adv Dent Res ; 23(2): 247-58, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21490237

RESUMO

The birth prevalence of orofacial clefts, one of the most common congenital anomalies, is approximately one in 700 live births, but varies with geography, ethnicity, and socio-economic status. There is a variation in infant mortality and access to care both between and within countries, so some clefts remain unrepaired into adulthood. Quality of care also varies, and even among repaired clefts there is residual deformity and morbidity that significantly affects some children. The two major issues in attempts to address these inequalities are (a) etiology/possibilities for prevention and (b) management and quality of care. For prevention, collaborative research efforts are required in developing countries, in line with the WHO approach to implement the recommendations of the 2008 Millennium Development Goals (www.un.org/millenniumgoals). This includes the "common risk factor" approach, which analyzes biological and social determinants of health alongside other chronic health problems such as diabetes and obesity, as outlined in the Marmot Health inequalities review (2008) (www.ucl.ac.uk/gheg/marmotreview). Simultaneously, orofacial cleft research should involve clinical researchers to identify inequalities in access to treatment and identify the best interventions for minimizing mortality and residual deformity. The future research agenda also requires engagement with implementation science to get research findings into practice.


Assuntos
Fissura Palatina/prevenção & controle , Fissura Palatina/terapia , Pesquisa em Odontologia , Saúde Global , Disparidades nos Níveis de Saúde , Saúde Bucal , Fenda Labial/epidemiologia , Fenda Labial/etiologia , Fenda Labial/prevenção & controle , Fenda Labial/terapia , Fissura Palatina/epidemiologia , Fissura Palatina/etiologia , Feminino , Predisposição Genética para Doença , Acessibilidade aos Serviços de Saúde , Humanos , Cooperação Internacional , Distúrbios Nutricionais/complicações , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Prevalência , Fatores Socioeconômicos , Pesquisa Translacional Biomédica
3.
J Nutr Health Aging ; 15(3): 202-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21369668

RESUMO

OBJECTIVE: To examine associations between frequency of ready-to-eat-cereal (RTEC) consumption and cognitive function among elderly men and women of the Cache County Study on Memory Health and Aging in Utah. DESIGN: A population-based prospective cohort study established in Cache County, Utah in 1995. SETTING AND PARTICIPANTS: 3831 men and women > 65 years of age who were living in Cache County, Utah in 1995. MEASUREMENT: Diet was assessed using a 142-item food frequency questionnaire at baseline. Cognitive function was assessed using an adapted version of the Modified Mini-Mental State examination (3MS) at baseline and three subsequent interviews over 11 years. RTEC consumption was defined as daily, weekly, or infrequent use. RESULTS: In multivariable models, more frequent RTEC consumption was not associated with a cognitive benefit. Those consuming RTEC weekly but less than daily scored higher on their baseline 3MS than did those consuming RTEC more or less frequently (91.7, 90.6, 90.6, respectively; p-value < 0.001). This association was maintained across 11 years of observation such that those consuming RTEC weekly but less than daily declined on average 3.96 points compared to an average 5.13 and 4.57 point decline for those consuming cereal more or less frequently (p-value = 0.0009). CONCLUSION: Those consuming RTEC at least daily had poorer cognitive performance at baseline and over 11 years of follow-up compared to those who consumed cereal more or less frequently. RTEC is a nutrient dense food, but should not replace the consumption of other healthy foods in the diets' of elderly people. Associations between RTEC consumption, dietary patterns, and cognitive function deserve further study.


Assuntos
Transtornos Cognitivos/epidemiologia , Dieta , Grão Comestível , Alimentos Fortificados , Fenômenos Fisiológicos da Nutrição/fisiologia , Idoso , Envelhecimento , Estudos de Coortes , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Utah/epidemiologia
4.
J Nutr Health Aging ; 13(10): 899-905, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19924351

RESUMO

OBJECTIVE: To examine associations between dietary and supplemental folate, vitamin B-12 and vitamin B-6 and incident Alzheimer's disease (AD) among elderly men and women. DESIGN, SETTING AND PARTICIPANTS: Data collected were from participants of the Cache County Memory, Health and Aging Study, a longitudinal study of 5092 men and women 65 years and older who were residents of Cache County, Utah in 1995. MEASUREMENTS: Multistage clinical assessment procedures were used to identify incident cases of AD. Dietary data were collected using a 142-item food frequency questionnaire. Cox Proportional Hazards (CPH) modeling was used to determine hazard ratios across quintiles of micronutrient intake. RESULTS: 202 participants were diagnosed with incident AD during follow-up (1995-2004). In multivariable CPH models that controlled for the effects of gender, age, education, and other covariates there were no observed differences in risk of AD or dementia by increasing quintiles of total intake of folate, vitamin B-12, or vitamin B-6. Similarly, there were no observed differences in risk of AD by regular use of either folate or B6 supplements. CONCLUSION: Dietary intake of B-vitamins from food and supplemental sources appears unrelated to incidence of dementia and AD. Further studies examining associations between dietary intakes of B-vitamins, biomarkers of B-vitamin status and cognitive endpoints are warranted.


Assuntos
Doença de Alzheimer/epidemiologia , Suplementos Nutricionais/estatística & dados numéricos , Ácido Fólico/administração & dosagem , Vitamina B 12/administração & dosagem , Vitamina B 6/administração & dosagem , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Estudos de Coortes , Dieta , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Memória/fisiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Inquéritos e Questionários , Utah
5.
J Exp Biol ; 212(Pt 5): 684-92, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19218520

RESUMO

After a meal, dogfish exhibit a metabolic alkalosis in the bloodstream and a marked excretion of basic equivalents across the gills to the external seawater. We used the H(+), K(+)-ATPase pump inhibitor omeprazole to determine whether these post-prandial alkaline tide events were linked to secretion of H(+) (accompanied by Cl(-)) in the stomach. Sharks were fitted with indwelling stomach tubes for pretreatment with omeprazole (five doses of 5 mg omeprazole per kilogram over 48 h) or comparable volumes of vehicle (saline containing 2% DMSO) and for sampling of gastric chyme. Fish were then fed an involuntary meal by means of the stomach tube consisting of minced flatfish muscle (2% of body mass) suspended in saline (4% of body mass total volume). Omeprazole pre-treatment delayed the post-prandial acidification of the gastric chyme, slowed the rise in Cl(-) concentration of the chyme and altered the patterns of other ions, indicating inhibition of H(+) and accompanying Cl(-) secretion. Omeprazole also greatly attenuated the rise in arterial pH and bicarbonate concentrations and reduced the net excretion of basic equivalents to the water by 56% over 48 h. Arterial blood CO(2) pressure (Pa(CO(2))) and plasma ions were not substantially altered. These results indicate that elevated gastric H(+) secretion (as HCl) in the digestive process is the major cause of the systemic metabolic alkalosis and the accompanying rise in base excretion across the gills that constitute the alkaline tide in the dogfish.


Assuntos
Álcalis/metabolismo , Digestão/fisiologia , Inibidores Enzimáticos/farmacologia , Omeprazol/farmacologia , Squalus acanthias/metabolismo , Animais , Digestão/efeitos dos fármacos , Conteúdo Gastrointestinal/química , Concentração de Íons de Hidrogênio , Inibidores da Bomba de Prótons , Água do Mar/química , Squalus acanthias/sangue , Estômago/química
6.
Am J Geriatr Psychiatry ; 16(11): 883-92, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18978249

RESUMO

BACKGROUND: Evidence suggests that cardiovascular medications, including statins and antihypertensive medications, may delay cognitive decline in patients with Alzheimer dementia (AD). We examined the association of cardiovascular medication use and rate of functional decline in a population-based cohort of individuals with incident AD. METHODS: In the Dementia Progression Study of the Cache County Study on Memory, Health, and Aging, 216 individuals with incident AD were identified and followed longitudinally with in-home visits for a mean of 3.0 years and 2.1 follow-up visits. The Clinical Dementia Rating (CDR) was completed at each follow-up. Medication use was inventoried during in-home visits. Generalized least-squares random-effects regression was performed with CDR Sum of Boxes (CDR-Sum) as the outcome and cardiovascular medication use as the major predictors. RESULTS: CDR-Sum increased an average of 1.69 points annually, indicating a steady decline in functioning. After adjustment for demographic variables and the baseline presence of cardiovascular conditions, use of statins (p = 0.03) and beta-blockers (p = 0.04) was associated with a slower annual rate of increase in CDR-Sum (slower rate of functional decline) of 0.75 and 0.68 points respectively, while diuretic use was associated with a faster rate of increase in CDR-Sum (p = 0.01; 0.96 points annually). Use of calcium-channel blockers, angiotensin-converting enzyme inhibitors, digoxin, or nitrates did not affect the rate of functional decline. CONCLUSIONS: In this population-based study of individuals with incident AD, use of statins and beta-blockers was associated with delay of functional decline. Further studies are needed to confirm these results and to determine whether treatment with these medications may help delay AD progression.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Doença de Alzheimer/psicologia , Doenças Cardiovasculares/tratamento farmacológico , Demência/psicologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/prevenção & controle , Estudos de Coortes , Demência/prevenção & controle , Feminino , Avaliação Geriátrica , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Análise Multivariada , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença
7.
Neurology ; 69(19): 1850-8, 2007 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-17984453

RESUMO

BACKGROUND: While there is considerable epidemiologic evidence that cardiovascular risk factors increase risk of incident Alzheimer disease (AD), few studies have examined their effect on progression after an established AD diagnosis. OBJECTIVE: To examine the effect of vascular factors, and potential age modification, on rate of progression in a longitudinal study of incident dementia. METHODS: A total of 135 individuals with incident AD, identified in a population-based sample of elderly persons in Cache County, UT, were followed with in-home visits for a mean of 3.0 years (range: 0.8 to 9.5) and 2.1 follow-up visits (range: 1 to 5). The Clinical Dementia Rating (CDR) Scale and Mini-Mental State Examination (MMSE) were administered at each visit. Baseline vascular factors were determined by interview and physical examination. Generalized least-squares random-effects regression was performed with CDR Sum of Boxes (CDR-Sum) or MMSE as the outcome, and vascular index or individual vascular factors as independent variables. RESULTS: Atrial fibrillation, systolic hypertension, and angina were associated with more rapid decline on both the CDR-Sum and MMSE, while history of coronary artery bypass graft surgery, diabetes, and antihypertensive medications were associated with a slower rate of decline. There was an age interaction such that systolic hypertension, angina, and myocardial infarction were associated with greater decline with increasing baseline age. CONCLUSION: Atrial fibrillation, hypertension, and angina were associated with a greater rate of decline and may represent modifiable risk factors for secondary prevention in Alzheimer disease. The attenuated decline for diabetes and coronary artery bypass graft surgery may be due to selective survival. Some of these effects appear to vary with age.


Assuntos
Doença de Alzheimer/epidemiologia , Doenças Cardiovasculares/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/epidemiologia , Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial/epidemiologia , Estudos de Coortes , Comorbidade , Ponte de Artéria Coronária/estatística & dados numéricos , Diabetes Mellitus/epidemiologia , Avaliação da Deficiência , Progressão da Doença , Feminino , Humanos , Hipertensão/epidemiologia , Incidência , Estudos Longitudinais , Masculino , Infarto do Miocárdio/epidemiologia , Testes Neuropsicológicos , Valor Preditivo dos Testes , Taxa de Sobrevida , Utah/epidemiologia
8.
J Nutr Health Aging ; 11(3): 230-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17508099

RESUMO

OBJECTIVE: We prospectively examined associations between intakes of antioxidants (vitamins C, vitamin E, and carotene) and cognitive function and decline among elderly men and women of the Cache County Study on Memory and Aging in Utah. PARTICIPANTS AND DESIGN: In 1995, 3831 residents 65 years of age or older completed a baseline survey that included a food frequency questionnaire and cognitive assessment. Cognitive function was assessed using an adapted version of the Modified Mini-Mental State examination (3MS) at baseline and at three subsequent follow-up interviews spanning approximately 7 years. Multivariable-mixed models were used to estimate antioxidant nutrient effects on average 3MS score over time. RESULTS: Increasing quartiles of vitamin C intake alone and combined with vitamin E were associated with higher baseline average 3MS scores (p-trend = 0.013 and 0.02 respectively); this association appeared stronger for food sources compared to supplement or food and supplement sources combined. Study participants with lower levels of intake of vitamin C, vitamin E and carotene had a greater acceleration of the rate of 3MS decline over time compared to those with higher levels of intake. CONCLUSION: High antioxidant intake from food and supplement sources of vitamin C, vitamin E, and carotene may delay cognitive decline in the elderly.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Carotenoides/administração & dosagem , Transtornos Cognitivos/prevenção & controle , Cognição/efeitos dos fármacos , Vitamina E/administração & dosagem , Idoso , Transtornos Cognitivos/etiologia , Escolaridade , Comportamento Alimentar , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Testes Psicológicos , Inquéritos e Questionários , Utah
9.
Respir Physiol Neurobiol ; 156(2): 220-8, 2007 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-17049933

RESUMO

In order to address the possible role of blood acid-base status in controlling the rectal gland, dogfish were fitted with indwelling arterial catheters for blood sampling and rectal gland catheters for secretion collection. In intact, unanaesthetized animals, isosmotic volume loading with 500 mmol L-1 NaCl at a rate of 15 mL kg-1 h-1 produced a brisk, stable rectal gland secretion flow of about 4 mL kg-1 h-1. Secretion composition (500 mmol L-1 Na+ and Cl-; 5 mmol L-1 K+; <1 mmol L-1 Ca2+, Mg2+, SO(4)2-, or phosphate) was almost identical to that of the infusate with a pH of about 7.2, HCO3- mmol L-1<1 mmol L-1 and a PCO2 (1 Torr) close to PaCO2. Experimental treatments superimposed on the infusion caused the expected disturbances in systemic acid-base status: respiratory acidosis by exposure to high environmental PCO2, metabolic acidosis by infusion of HCl, and metabolic alkalosis by infusion of NaHCO3. Secretion flow decreased markedly with acidosis and increased with alkalosis, in a linear relationship with extracellular pH. Secretion composition did not change, apart from alterations in its acid-base status, and made negligible contribution to overall acid-base balance. An adaptive control of rectal gland secretion by systemic acid-base status is postulated-stimulation by the "alkaline tide" accompanying the volume load of feeding and inhibition by the metabolic acidosis accompanying the volume contraction of exercise.


Assuntos
Equilíbrio Ácido-Base/fisiologia , Acidose Respiratória/sangue , Cação (Peixe)/fisiologia , Glândula de Sal/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Alcalose Respiratória/sangue , Animais , Glândula de Sal/metabolismo
10.
J Exp Biol ; 209(Pt 23): 4701-16, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17114403

RESUMO

We compared in vivo responses of rectal gland secretion to carbonic anhydrase (CA) inhibition (10(-4) mol l(-1) acetazolamide) in volume-loaded dogfish with in vitro responses in an isolated-perfused gland stimulated with 5 x 10(-6) mol l(-1) forskolin and removed from systemic influences. We also measured respiratory gas exchange in the perfused gland, described the acid-base status of the secreted fluid, and determined the relative importance of various extracellular and intracellular acid-base parameters in controlling rectal gland secretion in vitro. In vivo, acetazolamide inhibited Cl(-) secretion and decreased pHi in the rectal gland, but interpretation was confounded by an accompanying systemic respiratory acidosis, which would also have contributed to the inhibition. In the perfused gland, M(CO(2)) and M(O(2)) increased in linear relation to increases in Cl(-) secretion rate. CA inhibition (10(-4) mol l(-1) acetazolamide) had no effect on Cl(-) secretion rate or pHi in the perfused gland, in contrast to in vivo, but caused a transitory 30% inhibition of M(CO(2)) (relative to stable M(O(2))) and elevation in secretion P(CO(2)) effects, which peaked at 2 h and attenuated by 3.5-4 h. Secretion was inhibited by acidosis and stimulated by alkalosis; the relationship between relative Cl(-) secretion rate and pHe was almost identical to that seen in vivo. Experimental manipulations of perfusate pH, P(CO(2)) and HCO(3)(-) concentration, together with measurements of pHi, demonstrated that these responses were most strongly correlated with changes in pHe, and were not related to changes in P(CO(2)), extracellular HCO(3)(-), or intracellular HCO(3)(-) levels, though changes in pHi may also have played a role. The acid-base status of the secreted fluid varied with that of the perfusate, secretion pH remaining about 0.3-0.5 units lower, and changing in concert with pHe rather than pHi; secretion HCO(3)(-) concentrations remained low, even in the face of greatly elevated perfusate HCO(3)(-) concentrations. We conclude that pH effects on rectal gland secretion rate are adaptive, that CA functions to catalyze the hydration of CO(2), thereby maintaining a gradient for diffusive efflux of CO(2) from the working cells, and that differences in response to CA inhibition likely reflect the higher perfusion-to-secretion ratio in vitro than in vivo.


Assuntos
Equilíbrio Ácido-Base/fisiologia , Anidrases Carbônicas/metabolismo , Glândula de Sal/metabolismo , Squalus acanthias/metabolismo , Acetazolamida/farmacologia , Animais , Inibidores da Anidrase Carbônica/farmacologia , Glândula de Sal/efeitos dos fármacos
11.
Osteoporos Int ; 17(8): 1146-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16758135

RESUMO

INTRODUCTION: The associations between vitamin D receptor (VDR) Bsm I and Fok I genotypes, parity, and risk of osteoporotic hip fracture were evaluated in a statewide population-based case-control study in Utah. METHODS: Women age 50-89 years with hip fracture (n=882) were ascertained via surveillance of 18 Utah hospitals from 1997 to 2001. Age-matched controls were randomly selected (n=897). Participants were interviewed in their homes, and blood samples were collected for genotyping. RESULTS: In logistic regression analyses that controlled for multiple confounders, Bsm I VDR genotype but not Fok I genotype was associated with risk of osteoporotic hip fracture (OR bb vs. BB genotype: 0.68; 95% CI: 0.50, 0.95). In similar analyses, no overall association was observed between parity status and risk of osteoporotic hip fracture. However, the effect of VDR genotype was modified by parity status. Among nulliparous women (n=140), Bsm I genotype was not associated with risk of hip fracture (OR bb vs. BB: 0.82; 95% CI: 0.28, 2.4); among primiparous women (n=133), bb genotype was associated with increased risk of hip fracture (OR bb vs. BB: 3.30; 95% CI: 0.96, 11.29); among multiparous women (n=1,400), bb genotype was associated with decreased risk of hip fracture (OR bb vs. BB: 0.59; 95% CI: 0.42, 0.84). CONCLUSION: VDR Bsm I genotype was associated with risk of hip fracture in Utah women, and this effect was modified by parity status. Hormonal or lifestyle factors related to parity may underlie this interaction.


Assuntos
Fraturas do Quadril/etiologia , Osteoporose/etiologia , Paridade , Receptores de Calcitriol/genética , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Modelos Logísticos , Polimorfismo de Fragmento de Restrição , Gravidez , Risco
12.
J Chromatogr A ; 1101(1-2): 122-35, 2006 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-16236292

RESUMO

A general procedure is proposed for the rapid development of a reversed-phase liquid chromatographic (RP-LC) separation that is "orthogonal" to a pre-existing ("primary") method for the RP-LC separation of a given sample. The procedure involves a change of the mobile-phase organic solvent (B-solvent), the replacement of the primary column by one of very different selectivity, and (only if necessary) a change in mobile phase pH or the use of a third column. Following the selection of the "orthogonal" B-solvent, column and mobile phase pH, further optimization of peak spacing and resolution can be achieved by varying separation temperature and either isocratic %B or gradient time. The relative "orthogonality" of the primary and "orthogonal" RP-LC methods is then evaluated from plots of retention for one method versus the other. The present procedure was used to develop "orthogonal" methods for nine routine RP-LC methods from six pharmaceutical analysis laboratories. The relative success of this approach can be judged from the results reported here.


Assuntos
Cromatografia Líquida/métodos , Simulação por Computador , Contaminação de Medicamentos , Matemática , Preparações Farmacêuticas/isolamento & purificação , Sensibilidade e Especificidade , Solventes/química
13.
Gene Ther ; 13(4): 339-47, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16307001

RESUMO

Retinal ischemia results in the loss of vision in a number of ocular diseases including acute glaucoma, diabetic retinopathy, hypertensive retinopathy and retinal vascular occlusion. Recent studies have shown that most of the neuronal death that leads to loss of vision results from apoptosis. XIAP-mediated gene therapy has been shown to protect a number of neuronal types from apoptosis but has never been assessed in retinal neurons following ischemic-induced cell death. We injected an adeno-associated viral vector expressing XIAP or GFP into rat eyes and 6 weeks later, rendered them ischemic by raising intraocular pressure. Functional analysis revealed that XIAP-treated eyes retained larger b-wave amplitudes than GFP-treated eyes up to 4 weeks post-ischemia. The number of cells in the inner nuclear layer (INL) and the thickness of the inner retina were significantly preserved in XIAP-treated eyes compared to GFP-treated eyes. Similarly, there was no significant reduction in optic nerve axon numbers in XIAP-treated eyes. There were also significantly fewer TUNEL (TdT-dUTP terminal nick end labeling) positive cells in the INL of XIAP-treated retinas at 24 h post-ischemia. Thus, XIAP-mediated gene therapy imparts both functional and structural protection to the retina after a transient ischemic episode.


Assuntos
Terapia Genética/métodos , Isquemia/terapia , Neurônios/patologia , Retina/patologia , Doenças Retinianas/terapia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Animais , Contagem de Células , Dependovirus/genética , Eletrorretinografia , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Marcação In Situ das Extremidades Cortadas , Injeções , Isquemia/metabolismo , Isquemia/patologia , Masculino , Neurônios/metabolismo , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Ratos , Ratos Sprague-Dawley , Retina/metabolismo , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
15.
Brain Res ; 1008(2): 139-46, 2004 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-15145750

RESUMO

During embryogenesis, transient expression of nestin in proliferating neuroepithelial stem cells signals the commitment of progenitor cells to differentiate. Although adult mammalian brain contains very little nestin, significant upregulation of nestin has been reported following cerebral injury, leading to speculation that nestin may be involved in brain repair. In this study, we assessed the temporal profile of nestin expression following ablation injury of the sensory barrel cortex and investigated the influence of contralateral whisker stimulation on nestin expression. Since the adult mammalian brain contains proliferating neuronal progenitor cells that can be labeled with bromodeoxyuridine (BrdU), we also determined the association of nestin reexpression with BrdU-labeled cells. Nestin reexpression was detected predominantly in the ipsilateral cortex 3 days post-ablation. There was no significant nestin upregulation in the subcortical region. Nestin reexpression was most marked surrounding the lesion, but also extended throughout the entire lateral cortex. Nestin in the ipsilateral cortex subsided by day 7, although perilesional nestin expression was still apparent 28 days post-injury. Western blot analysis of nestin expression 3 days post-ablation confirmed a significant two-fold increase in nestin expression (p<0.05). Double immunofluorescence labeling demonstrated that the majority of nestin expression occurred in astrocytes. We were unable to detect any colocalization with neuronal makers. However, BrdU-labeled cells, which were readily detected in the subventricular zone prior to injury, were readily detected in the perilesional area 3 days post-ablation, concomitant with nestin in this area. Confocal microscopy detected several BrdU-positive cells expressing nestin. Taken together, the data support a potential role for nestin reexpression in brain repair.


Assuntos
Química Encefálica/fisiologia , Córtex Cerebral/fisiologia , Proteínas de Filamentos Intermediários/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Animais , Antimetabólitos , Western Blotting , Bromodesoxiuridina , Desoxiglucose/farmacologia , Imunofluorescência , Imuno-Histoquímica , Indicadores e Reagentes , Masculino , Microscopia Confocal , Córtex Motor/fisiologia , Regeneração Nervosa/fisiologia , Nestina , Estimulação Física , Ratos , Ratos Wistar , Células-Tronco/fisiologia , Vibrissas/fisiologia
16.
Int J Artif Organs ; 26(8): 764-73, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14521175

RESUMO

Stabilized collagen-glycosaminoglycan scaffolds for tissue engineered human corneas were characterized. Hydrated matrices were constructed by blending type I collagen with chondroitin sulphates (CS), with glutaraldehyde crosslinking. A corneal keratocyte cell line was added to the scaffolds with or without corneal epithelial and endothelial cells. Constructs were grown with or without ascorbic acid. Wound-healing was evaluated in chemical-treated constructs. Native, noncrosslinked gels were soft with limited longevity. Crosslinking strengthened the matrix yet permitted cell growth. CS addition increased transparency. Keratocytes grown within the matrix had higher frequencies of K+ channel expression than keratocytes grown on plastic. Ascorbic acid increased uncrosslinked matrix degradation in the presence of keratocytes, while it enhanced keratocyte growth and endogenous collagen synthesis in crosslinked matrices. Wounded constructs showed recovery from exposure to chemical irritants. In conclusion, this study demonstrates that our engineered, stabilized matrix is well-suited to function as an in vitro corneal stroma.


Assuntos
Colágeno , Substância Própria/citologia , Engenharia Tecidual/métodos , Animais , Ácido Ascórbico/farmacologia , Bovinos , Substância Própria/fisiologia , Eletrofisiologia , Matriz Extracelular , Glicosaminoglicanos , Hidrogéis , Análise dos Mínimos Quadrados , Cicatrização/fisiologia
17.
Am J Clin Nutr ; 74(6): 808-13, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11722964

RESUMO

BACKGROUND: Before its recognition, infantile beriberi was the leading cause of infant death in camps for displaced persons of the Karen ethnic minority on Thailand's western border. OBJECTIVE: This study aimed to document thiamine status in the peripartum period to examine the current supplementation program and the correlation between the clinical manifestations of thiamine deficiency and a biochemical measure of thiamine status. DESIGN: Women were enrolled prospectively at 30 wk of gestation and were followed up weekly until delivery and at 3 mo postpartum. Thiamine supplementation during pregnancy was based on patient symptoms. RESULTS: At 3 mo postpartum, thiamine deficiency reflected by an erythrocyte transketolase activity (ETKA) > or = 1.20% was found in 57.7% (15/26) of mothers, 26.9% (7/26) of whom had severe deficiency (ETKA > 1.25%). No significant associations between ETKA and putative maternal symptoms or use of thiamine supplements were found. CONCLUSIONS: Biochemical postpartum thiamine deficiency is still common in Karen refugee women. This situation may be improved by educating lactating women to reduce their consumption of thiaminase-containing foods and by implementing an effective thiamine supplementation program.


Assuntos
Lactação/sangue , Gravidez/sangue , Refugiados , Deficiência de Tiamina/epidemiologia , Tiamina/administração & dosagem , Adolescente , Adulto , Estudos de Coortes , Suplementos Nutricionais , Eritrócitos/enzimologia , Feminino , Humanos , Hidrolases/administração & dosagem , Hidrolases/efeitos adversos , Recém-Nascido , Leite Humano/química , Período Pós-Parto , Resultado da Gravidez , Cuidado Pré-Natal , Estudos Prospectivos , Tailândia/epidemiologia , Deficiência de Tiamina/sangue , Deficiência de Tiamina/tratamento farmacológico , Transcetolase/sangue
19.
J Cataract Refract Surg ; 27(8): 1254-62, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11524199

RESUMO

PURPOSE: To investigate the effect of hyperopic photorefractive keratectomy (PRK) on intraocular pressure (IOP) measurements. SETTING: University of Ottawa Eye Institute, Ottawa Hospital, Ottawa, Canada. METHODS: In this retrospective cohort study, IOP and central corneal thickness (CCT) were measured preoperatively and at 1, 2, 3, 6, 12, 18, and 24 months in 191 eyes that had hyperopic PRK with the VISX Star excimer laser. All corrections applied were between +1.00 and +6.50 diopters (D) of sphere and less than 3.75 D of cylinder. RESULTS: At all postoperative examinations, the mean IOP in the hyperopic PRK group was 1.0 to 1.8 mm Hg lower than the preoperative IOP (P <.001). A large range of IOP changes was found across the population; eg, at 6 months, 49% of the eyes had a change in IOP from baseline of at least +/-3 mm Hg. A mean reduction of 19 microm of CCT was found with pachymetry after surgery (P < .001). The change in IOP readings postoperatively was not correlated with age, sex, keratometric readings, or applied correction. Changes in IOP were strongly correlated with preoperative IOP at all time points and with preoperative CCT at 18 and 24 months (P < .001). After hyperopic PRK, the measured IOP was more likely to increase in patients with preoperative IOPs less than 14.5 mm Hg and more likely to decrease in patients with preoperative IOPs above 14.5 mm Hg. CONCLUSION: Changes in IOP after hyperopic PRK were similar to changes after myopic PRK, despite only minimal changes in the CCT. This suggests that hyperopic PRK results in biomechanical effects that modify the elastic properties of the cornea beyond the changes in rigidity expected from central corneal thinning. There was a strong negative correlation between the measured preoperative IOP and the change in IOP postoperatively that was likely the result of regression of the mean effect.


Assuntos
Córnea/cirurgia , Hiperopia/cirurgia , Pressão Intraocular/fisiologia , Ceratectomia Fotorrefrativa , Estudos de Coortes , Humanos , Lasers de Excimer , Pessoa de Meia-Idade , Estudos Retrospectivos , Tonometria Ocular , Acuidade Visual
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