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1.
Int J Obes (Lond) ; 38(7): 944-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24480862

RESUMEN

OBJECTIVE: We investigate whether differences in sleep duration help explain ethnic disparities in body mass index (BMI) among US adolescents. We also evaluate the functional form of the association between sleep duration and BMI, and investigate whether this association varies by sex and ethnicity. PARTICIPANTS AND METHODS: We analyzed restricted-use data from the first two waves of the National Longitudinal Study of Adolescent Health (n=30 133) to evaluate linear and quadratic associations between sleep duration and BMI. Through a series of models that incorporated interaction terms between sex, ethnicity and sleep duration, we also assessed whether (1) sleep duration mediates associations between ethnicity and BMI, and (2) associations between sleep duration and BMI differ for girls and boys from different ethnic groups. RESULTS: A linear association between sleep duration and BMI best fits the data in this large sample of US adolescents. We find no evidence that sleep duration contributes substantially to ethnic disparities in BMI. However, we detect significant differences in the association between sleep duration and BMI by sex and ethnicity. Sleep duration is negatively associated with BMI among White, Hispanic and Asian boys, positively associated with BMI among Black girls and is not related to BMI among Black boys or girls from White, Hispanic or Asian ethnic groups. CONCLUSIONS: Despite significant associations between sleep duration and BMI for certain groups of adolescents, we find no evidence that ethnic differences in sleep duration exacerbate ethnic disparities in BMI. Future research should explore mechanisms that underlie ethnic differences in the association between sleep and BMI.


Asunto(s)
Negro o Afroamericano , Índice de Masa Corporal , Hispánicos o Latinos , Sobrepeso/etnología , Pubertad , Sueño , Población Blanca , Adolescente , Etnicidad , Femenino , Disparidades en el Estado de Salud , Humanos , Estudios Longitudinales , Masculino , Sobrepeso/prevención & control , Factores Sexuales , Factores Socioeconómicos , Estados Unidos/epidemiología , Estados Unidos/etnología
2.
Klin Monbl Augenheilkd ; 231(10): 1016-22, 2014 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-25178045

RESUMEN

MR microscopy using an ultra high-field MR system is a novel non-invasive imaging technique to explore the human eye without optical distortions. This review aims to provide an insight into the technique. Normal MR microscopic anatomy of the human eye in vivo is demonstrated and clinical applications of MR microscopy are discussed.


Asunto(s)
Ojo/citología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Microscopía/métodos , Oftalmoscopía/métodos , Humanos
3.
Klin Monbl Augenheilkd ; 231(12): 1187-95, 2014 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-25519506

RESUMEN

This review documents technical progress in ophthalmic magnetic resonance imaging (MRI) at ultrahigh fields (UHF, B(0) ≥ 7.0 T). The review surveys frontier applications of UHF-MRI tailored for high spatial resolution in vivo imaging of the eye, orbit and optic nerve. Early examples of clinical ophthalmic UHF-MRI including the assessment of melanoma of the choroid membrane and the characterisation of intraocular masses are demonstrated. A concluding section ventures a glance beyond the horizon and explores research promises along with future directions of ophthalmic UHF-MRI.


Asunto(s)
Neoplasias del Ojo/patología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Oftalmoscopía/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Evaluación de la Tecnología Biomédica
4.
J Hand Surg Am ; 37(8): 1561-7, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22749480

RESUMEN

PURPOSE: Wrist ganglions are the most common soft tissue tumors of the hand and wrist and can occur at any age. Their etiology remains controversial. A high prevalence of associated intrinsic ligamentous lesions has been described. We hypothesized that painful wrist ganglions are an indicator of an underlying joint abnormality, particularly of lesions of the triangular fibrocartilage complex (TFCC). The aim of our study was to prospectively determine the prevalence of associated TFCC lesions in patients with painful wrist ganglions. METHODS: Forty-six patients (35 women, 11 men; mean age, 36 ± 11 y; range, 18-57 y) with painful wrist ganglions (20 radiopalmar and 26 dorsal) had surgery from January 2008 to June 2010. There were 18 primary and 28 recurrent ganglions. Clinical examinations, pain score evaluations, disabilities in daily life evaluations, plain radiographs, and magnetic resonance imaging were obtained before arthroscopic resection. Concomitant intrinsic lesions of the wrist were assessed with magnetic resonance imaging and re-evaluated by arthroscopy. RESULTS: All ganglions were successfully resected. Overall, arthroscopy identified 22 TFCC lesions (48%) and 2 intracarpal ligament lesions. The TFCC perforations were more commonly associated with radiopalmar ganglions with a positive ulnocarpal stress test result and with recurrent radiopalmar ganglions. At 1-year follow-up, all patients were meaningfully improved in terms of pain and disabilities in daily life. CONCLUSIONS: Arthroscopy allows for the simultaneous treatment of ganglions and other pathologies. Therefore, arthroscopy should be contemplated as the primary treatment option for patients with painful ganglions of the wrist if they are in a radiopalmar location with a positive ulnocarpal stress test and for patients with recurrent radiopalmar ganglions, which are also highly associated with TFCC abnormalities. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Artroscopía/métodos , Ganglión/cirugía , Fibrocartílago Triangular/cirugía , Muñeca/cirugía , Adolescente , Adulto , Evaluación de la Discapacidad , Femenino , Ganglión/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Estadísticas no Paramétricas , Resultado del Tratamiento , Fibrocartílago Triangular/anomalías , Muñeca/patología
5.
BJOG ; 118(8): 966-77, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21489126

RESUMEN

OBJECTIVE: To examine the relationship between delivery mode and postpartum depression at 6 weeks following hospital discharge. DESIGN: A prospective cohort study. SETTING: Eleven hospitals in Ontario, Canada. SAMPLE: A total of 2560 women ≥16 years of age who delivered singleton, live infants at term. METHODS: Women completed a questionnaire in hospital and 74% (n = 1897) participated in a structured telephone interview 6 weeks after discharge. Additional data were extracted from labour and delivery records. Generalised estimating equations (GEEs) were used to investigate factors associated with postpartum depression. MAIN OUTCOME MEASURE: Women were screened for depression at 6 weeks following hospital discharge using the Edinburgh Postnatal Depression Scale (EPDS). A score of ≥12 on the EPDS was used as a measure of the primary outcome, depression. RESULTS: Mode of delivery was not independently associated with postpartum depression, and did not factor into the main-effects model. The multivariable analysis identified 11 predictor variables for depression: young maternal age (OR 5.27; 95% CI 2.73-10.15); maternal hospital readmission (OR 3.02; 95% CI 1.46-6.24); non-initiation of breastfeeding (OR 2.02; 95% CI 0.99-4.11); good, fair, or poor self-reported postpartum health (OR 1.82; 95% CI 1.19-2.80); urinary incontinence (OR 1.79; 95% CI 1.06-3.03); multiparity (OR 1.59; 95% CI 1.22-2.08); low mental health functioning (OR 1.20; 95% CI 1.15-1.25); low subjective social status (OR 1.16; 95% CI 1.02-1.33); high number of unmet learning needs in hospital (OR 1.12; 95% CI 1.03-1.22); low social support (OR 1.06; 95% CI 1.03-1.09); and low physical health functioning (OR 1.03; 95% CI 1.003-1.055). An exploratory interaction model revealed that caesarean section was associated with higher odds of becoming depressed in Canadian-born women, but that in women born outside of Canada it was associated with a lower risk of becoming depressed. CONCLUSIONS: Delivery mode had no significant impact on the development of postpartum depression in the main-effects model. However, it may interact with place of birth and other unmeasured factors to create a risk for depression.


Asunto(s)
Parto Obstétrico/métodos , Parto Obstétrico/estadística & datos numéricos , Depresión Posparto/epidemiología , Adulto , Cesárea/estadística & datos numéricos , Estudios de Cohortes , Depresión Posparto/diagnóstico , Femenino , Humanos , Recién Nacido , Ontario/epidemiología , Embarazo , Estudios Prospectivos , Medición de Riesgo , Encuestas y Cuestionarios
6.
Klin Monbl Augenheilkd ; 228(12): 1073-8, 2011 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-22095150

RESUMEN

Ultra-high-field MR microscopy is a novel, non-invasive imaging technique to explore the strcutures of the human eye without optical distorsions. This review aims to provide an insight into the technique of the method. The normal MR microscopic anatomy of the human eye with correlations to histology is demonstrated. The use of MR microscopy in ther experimental ophthalmological setting is discussed.


Asunto(s)
Segmento Anterior del Ojo/patología , Neoplasias del Ojo/patología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Microscopía/métodos , Humanos
7.
J Exp Biol ; 213(Pt 7): 1079-91, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20228344

RESUMEN

Understanding the extent to which changes in muscle form and function underlie ontogenetic changes in locomotory behaviors and performance is important in understanding the evolution of musculoskeletal systems and also the ecology of different life stages. We explored ontogenetic changes in the structure, myosin heavy chain (MHC) expression and contractile properties of the circular muscles that provide power for jet locomotion in the long-finned squid Doryteuthis pealeii. The circular muscle fibers of newly hatched paralarvae had different sizes, shapes, thick filament lengths, thin:thick filament ratio, myofilament organization and sarcoplasmic reticulum (SR) distribution than those of adults. Viewed in cross section, most circular muscle cells were roughly triangular or ovoid in shape with a core of mitochondria; however, numerous muscle cells with crescent or other unusual cross-sectional shapes and muscle cells with unequal distributions of mitochondria were present in the paralarvae. The frequency of these muscle cells relative to 'normal' circular muscle cells ranged from 1:6 to 1:10 among the 19 paralarvae we surveyed. The thick filaments of the two types of circular fibers, superficial mitochondria-rich (SMR) and central mitochondria-poor (CMP), differed slightly in length among paralarvae with thick filament lengths of 0.83+/-0.15 microm and 0.71+/-0.1 microm for the SMR and CMP fibers, respectively (P 0.05; ANOVA). During ontogeny the thick filament lengths of both the CMP and SMR fibers increased significantly to 1.78+/-0.27 microm and 3.12+/-0.56 microm, respectively, in adults (P<0.0001 for both comparisons; ANOVA with Tukey's highly significant difference post hoc tests). When sectioned parallel to their long axes, the SMR and CMP fibers of both paralarvae and adults exhibited the myofilament arrangements typical of obliquely striated muscle cells but the angle of obliquity of the dense bodies was 22.8+/-2.4 deg. and 4.6+/-0.87 deg. for paralarvae and adults, respectively. There were also differences in the distribution of the anastomosing network of SR. In paralarvae, the outer and central zones of SR were well developed but the intramyoplasmic zone was greatly reduced in some cells or was scattered non-uniformly across the myoplasm. Whereas in adults the intramyoplasmic SR region was composed primarily of flattened tubules, it was composed primarily of rounded vesicles or tubules when present in the paralarvae. The ontogenetic differences in circular muscle structure were correlated with significant differences in their contractile properties. In brief tetanus at 20 degrees C, the mean unloaded shortening velocity of the paralarval circular muscle preparations was 9.1 L(0) s(-1) (where L(0) was the preparation length that generated the peak isometric stress), nearly twice that measured in other studies for the CMP fibers of adults. The mean peak isometric stress was 119+/-15 mN mm(-2) physiological cross section, nearly half that measured for the CMP fibers of adults. Reverse transcriptase-polymerase chain reaction analysis of paralarval and adult mantle samples revealed very similar expression patterns of the two known isoforms of squid MHC. The ontogenetic differences in the structure and physiology of the circular muscles may result in more rapid mantle movements during locomotion. This prediction is consistent with jet pulse durations observed in other studies, with shorter jet pulses providing hydrodynamic advantages for paralarvae.


Asunto(s)
Estructuras Animales/anatomía & histología , Estructuras Animales/fisiología , Decapodiformes/anatomía & histología , Decapodiformes/fisiología , Locomoción/fisiología , Músculos/anatomía & histología , Músculos/fisiología , Animales , Regulación de la Expresión Génica , Larva/fisiología , Larva/ultraestructura , Modelos Biológicos , Contracción Muscular/fisiología , Fibras Musculares Esqueléticas/fisiología , Fibras Musculares Esqueléticas/ultraestructura , Músculos/ultraestructura , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Tiempo
8.
Biochim Biophys Acta ; 393(2): 274-83, 1975 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-1148218

RESUMEN

Infrared absorption spectroscopy has been used to study the effect of organic solvents on the conformation of myoglobin, apomyoglobin, hemoglobin, lysozyme and ribonuclease. Beta structure can easily be induced by specific solvent effects. Films prepared from a 50% (v/v) mixture of alcohol, acetone, pyridine, tetrahydrofuran or dimethylsulfoxide/water mixtures show a high proportion of beta structure. The degree of induction of beta structure depends on the hydrocarbon content of the alcohol in the order methanol greater than ethanol greater than butanol. No beta structure was observed in films prepared from aqueous octanol solutions. Lyophilization tends to decrease secondary structure. The conformation of the proteins depends on the particular solvent system and the solvent composition. Solution studies of myoglobin in pure dimethylsulfoxide show that the conformation is a mixture of random and beta forms while in dimethylsulfoxide/2H2O mixtures the conformation is a mixture of alpha-helical and beta forms.


Asunto(s)
Globulinas , Acetona/farmacología , Alcoholes/farmacología , Apoproteínas , Deuterio/farmacología , Dimetilsulfóxido/farmacología , Liofilización , Furanos/farmacología , Hemoglobinas , Hidrocarburos/farmacología , Muramidasa , Mioglobina , Conformación Proteica/efectos de los fármacos , Piridinas/farmacología , Ribonucleasas , Albúmina Sérica Bovina , Solventes , Espectrofotometría Infrarroja
9.
Transplantation ; 61(8): 1215-21, 1996 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-8610421

RESUMEN

Bovine adrenal chromaffin (BAC) cells were encapsulated in polymer membranes and placed into the lumbar intrathecal (subarachnoid) space of sheep for up to 12 weeks in the absence of immunosuppression. Humoral and cellular immunological responses in the sheep were evaluated over this time course using the following assays: (1) serum-dependent cytotoxic antibody determinations, (2) flow cytometric sheep anti-bovine IgM and sheep antibovine IgG antibody analysis, (3) alterations in cellular immune markers, and (4) T cell responsiveness of the host using one-way mixed lymphocyte reactions. Complement-dependent cytotoxic antibody testing demonstrated that none of the sheep implanted with the encapsulated BAC cells were sensitized to antigens from transplanted cells in the device. There were no alterations of cellular immune markers in the blood of the transplanted sheep and no positive T cell responses were elicited by exposure of unprimed or primed in vivo host lymphocytes to unencapsulated BAC cells in vitro. Morphological analysis of the explanted devices demonstrated that all capsules contained viable cells and 20 of 21 devices released basal and nicotine-stimulated norepinephrine as determined by HPLC analysis. These observations suggest that an encapsulating membrane can provide an immunoisolatory barrier enabling successful xenogeneic transplantation.


Asunto(s)
Médula Suprarrenal/trasplante , Trasplante de Células/métodos , Linfocitos T/inmunología , Trasplante Heterólogo/inmunología , Médula Suprarrenal/inmunología , Animales , Bovinos , Inmunidad , Región Lumbosacra , Ovinos
10.
Ann Epidemiol ; 7(6): 400-6, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9279449

RESUMEN

PURPOSE: The relationship among young age, biologic immaturity (as indexed by low gynecologic age), and the causes of preterm delivery (idiopathic preterm labor [PTL], premature rupture of the membranes [PROM], and medical indications) were investigated among 605 primigravidas from the Camden Study. METHODS: The sample consisted of 366 young adolescents < 16 years at the time of their last menstrual period (LMP) and 239 older women, 18-29 years at LMP (controls). The young adolescents were significantly shorter, thinner, had younger ages at menarche, and over a third (36.3%) were of low gynecologic age, i.e., their chronologic age was 2 or fewer years more than their age at menarche. RESULTS: Adjusting for ethnicity, cigarettes smoked/day, weight gain rate, height, fetal sex, gestational diabetes mellitus, and pregnancy-induced hypertension, young adolescents overall had a nearly 75% increased risk of PTL (adjusted odds ratio [AOR] = 1.74, 95% confidence interval [95% CI]: 1.07-2.84), and preterm delivery with PTL (AOR = 2.08, 95% CI: 1.08-4.00). There was a modest decreased risk of preterm delivery among young gravidas attributable to other causes, such as PROM or medical indications (AOR = 0.70, 95% CI: 0.28-1.75). This increased risk of PTL and preterm delivery with PTL was principally attributable to biologic immaturity. Young age with low gynecologic age was associated with a twofold risk of PTL (AOR = 2.15, 95% CI: 1.19-3.89) and preterm delivery with PTL (AOR = 2.64, 95% CI: 1.23-5.65), while the risk associated with young age and higher gynecologic age was only increased moderately. CONCLUSIONS: Young adolescents, and especially those of low gynecologic age, appear prone to PTL and are at increased risk for preterm delivery through this pathway.


PIP: The relationship between young maternal age and preterm delivery was investigated in a subsample of 605 primigravidas enrolled in the Camden (New Jersey, US) Study. Included were 366 adolescents under 16 years of age (cases) and 239 women 18-29 years of age (controls). 36.3% of young mothers had a low gynecological age (i.e., their chronological age was 2 or fewer years more than their age at menarche). After adjustment for ethnicity, cigarette smoking, weight gain rate, height, fetal sex, gestational diabetes mellitus, and pregnancy-induced hypertension, the odds ratio (OR) of preterm labor among young adolescents was 1.74 (95% confidence interval (CI), 1.07-2.84) and that of preterm delivery was 2.08 (95% CI, 1.08-4.00). There was a modest decreased risk of preterm delivery attributable to other causes (e.g., premature rupture of the membranes) among the youngest women (OR, 0.70; 95% CI, 0.28-1.75). Young age with low gynecological age was associated with a 2.15 OR (95% CI, 1.19-3.89) of preterm labor and a 2.64 OR (95% CI, 1.23-5.65) of preterm delivery with preterm labor. The risk associated with young age and higher gynecological age was increased only moderately. These findings suggest that it is the biological immaturity often associated with young age, rather than young maternal age per se, that increases the risks of adolescent pregnancy. The association between low gynecological age and preterm labor is presumed to reflect an irritability of the adolescent uterus, a sensitivity to dehydration, and/or an altered hormonal milieu that promotes maternal development at the expense of fetal well-being.


Asunto(s)
Edad Materna , Trabajo de Parto Prematuro/epidemiología , Adolescente , Adulto , Análisis de Varianza , Estatura , Peso Corporal , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Rotura Prematura de Membranas Fetales/epidemiología , Humanos , Modelos Logísticos , Embarazo , Embarazo en Adolescencia , Factores de Riesgo
11.
J Am Geriatr Soc ; 47(5): 547-52, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10323647

RESUMEN

OBJECTIVE: To describe outbreaks of infection caused by Legionella sainthelensi occurring in older residents of two nursing homes and to determine risk factors for the development of infection. DESIGN: Descriptive epidemiology and a case-control study. SETTING: Two nursing homes (140 beds and 254 beds in nursing homes A and B, respectively) located in southern Ontario, Canada, experiencing outbreaks of respiratory tract infection in July and August 1994. SUBJECTS: Case-residents of the two nursing homes who met clinical and laboratory criteria for Legionella infection. Control-residents were defined as those who were in the homes during the outbreaks and were asymptomatic. MEASUREMENTS: Active surveillance was conducted in both nursing homes to identify symptomatic residents. Residents with fever or respiratory tract symptoms had nasopharyngeal swabs taken for viral antigen detection and culture, urine for Legionella antigen detection, and acute and convalescent serology for viruses, Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella. Chest X-rays were performed, and an attempt was made to obtain blood and sputum cultures. Water samples from shower heads, faucets, and air conditioning units were collected for Legionella culture and polymerase chain reaction (PCR) assay. A case-control study was done to assess possible risk factors for legionellosis. RESULTS: Twenty-nine cases -- 17 in nursing home A; 12 in nursing home B - were identified. Four (14%) case-residents had documented pneumonia and four case-residents died. Univariate analysis revealed that a history of stroke (odds ratio (OR) 2.3 (95% CI, 1.0-5.3)), eating pureed food (OR 4.6 (95% CI, 1.6-12.7)), and having fluids administered with medication (OR 2.5 (95% CI, 1.0-5.9)) were significant risk factors. Cases were less likely to wear dentures (OR .4 (95% CI, .2-.9)) or to eat solid food (OR .3, (95% CI, .1-.6)). Only eating pureed food remained significant in a multivariable analysis (OR 4.6 (95% CI, 1.6-13.0, P = .01)). CONCLUSION: This report describes outbreaks of legionellosis in two nursing homes, representing the first reported outbreaks of infection caused by Legionella sainthelensi. The association with illness of dietary characteristics indicative of swallowing disorders suggests that aspiration was the most likely mode of infection. The diagnosis of legionellosis should be considered during outbreaks of respiratory infection in nursing homes.


Asunto(s)
Infección Hospitalaria/epidemiología , Hogares para Ancianos , Legionelosis/epidemiología , Casas de Salud , Infecciones del Sistema Respiratorio/epidemiología , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Estudios de Casos y Controles , Infección Hospitalaria/diagnóstico , Femenino , Humanos , Legionella/aislamiento & purificación , Legionelosis/diagnóstico , Masculino , Infecciones del Sistema Respiratorio/diagnóstico , Factores de Riesgo
12.
Restor Neurol Neurosci ; 11(1): 21-35, 1997 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21551525

RESUMEN

Numerous studies have reported that adrenal chromaffin cell transplants, including encapsulated xenogeneic adrenal chromaffin cells, have analgesic effects. However, in addition to efficacy, the clinical utility of encapsulated xenogeneic adrenal chromaffin cells for treatment of chronic pain is dependent on the duration of cell viability in vivo, and their relative safety. The objectives of the present study in rats were to: (1) examine encapsulated calf adrenal chromaffin (CAC) cells for evidence of viable cells and continued release of analgesic agents after an extended period in vivo; (2) determine if intraventricular encapsulated CAC cells produce detectable adverse effects on behavioral/cognitive function; and (3) test for evidence of host immune sensitization after an extended period of exposure to encapsulated xenogeneic adrenal chromaffin cells. Results of the present study suggest that some encapsulated CAC cells remain viable for nearly 1.5 years in vivo and continue to produce catecholamines and met-enkephalin. Post-explant device norepinephrine output was equivalent to amounts previously shown to produce analgesic effects with intrathecal implants. Encapsulated adrenal chromaffin cells also appeared relatively safe, even when implanted in the cerebral ventricals, with a lower side-effect profile than systemic morphine (4 mg/kg). There was no evidence that encapsulated CAC-cells implanted in the ventricles affected body weight, spontaneous activity levels, or performance in the delayed matching to position operant task which is sensitive to deficits in learning, memory, attention, motivation, and motor function. Finally, encapsulated CAC cells produced no detectable evidence of host immune sensitization after 16.7 months in vivo, although unencapsulated CAC cells produced a robust immune response even in aged rats. The results of the present study suggest that adrenal chromaffin cells remain viable in vivo for long periods of time, and that long-term exposure to encapsulated xenogeneic adrenal chromaffin cell implants appears relatively safe.

13.
Artículo en Inglés | MEDLINE | ID: mdl-7972863

RESUMEN

1. The feasibility of ameliorating the motor deficits in aged rats was evaluated in animals receiving polymer-encapsulated PC12 cells. 2. Motor coordination and balance was evaluated in young (5-6 month) and aged (24-25 month) rats. Compared to the young animals, the aged animals fell more rapidly from a rotating rod and were unable to maintain their balance on a series of wooden beams of varying widths. 3. Following baseline testing, aged animals received either no implant, empty capsules or PC12 cell-loaded capsules implanted bilaterally into the striatum. 4. Three weeks following surgery, animals were re-tested and a significant improvement in balance on the rotorod and wooden beams was observed in those aged animals receiving PC12 cell-loaded capsules. No improvements or decrements in performance were observed in those animals receiving empty. Histological analysis revealed the presence of surviving tyrosine hydroxylase-positive PC12 cells randomly distributed within the capsules.


Asunto(s)
Neostriado/fisiología , Células PC12 , Desempeño Psicomotor/fisiología , Animales , Quelantes , Quitina/análogos & derivados , Quitosano , Dopamina/metabolismo , Inmunohistoquímica , Masculino , Actividad Motora/fisiología , Neostriado/anatomía & histología , Equilibrio Postural/fisiología , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/metabolismo
14.
J Epidemiol Community Health ; 58(3): 223-30, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14966236

RESUMEN

OBJECTIVE: To examine whether measures of neighbourhood economic deprivation, social disorganisation, and acculturation explain homicide mortality differentials between Mexican Americans, non-Hispanic black Americans, and non-Hispanic white Americans, net of individual factors. DESIGN: Prospective study, National Health Interview Survey (1986-1994) linked to subsequent mortality in the National Death Index (1986-1997). SETTING: United States of America. PARTICIPANTS: A nationally representative sample of non-institutionalised Mexican Americans, non-Hispanic black Americans, and non-Hispanic white Americans, aged 18-50 at the point of interview. ANALYSIS: Cox proportional hazard models estimate the risk of death associated with various neighbourhood and individual factors. MAIN RESULTS: Both individual and neighbourhood risk factors partially account for race/ethnic disparities in homicide. Homicide mortality risks are between 20% and 50% higher for residents of areas that have economic inequality of 0.50 or greater based on the coefficient of variation, or where 4% or more of the residents are Mexican American, 10% or more of the residents are non-Hispanic black, or 20% or more of the households are headed by single parents (p< or = 0.05). But residents of areas where 10% or more of their neighbours are foreign born have 35% lower mortality risks than people living in areas with fewer foreign born people (p< or =0.05). These differences persist even after controlling for individual level risk factors. CONCLUSIONS: The findings support economic deprivation, social disorganisation, and acculturation theories, and suggest that both neighbourhood and individual risk factors affect race/ethnic differences in homicide mortality. Public health policies must focus on both individual and neighbourhood factors to reduce homicide risks in vulnerable populations.


Asunto(s)
Homicidio/etnología , Características de la Residencia , Adolescente , Adulto , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Homicidio/estadística & datos numéricos , Humanos , Masculino , Americanos Mexicanos/estadística & datos numéricos , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Factores Socioeconómicos , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos
15.
Brain Res Bull ; 32(5): 477-86, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8221140

RESUMEN

Spontaneous locomotion and motor coordination was evaluated in young (5-6 month old) and aged (24-25 month old) rats. Animals were tested for spontaneous locomotor activity in Digiscan Animal Activity Monitors during the nocturnal cycle. Aged animals exhibited a significant hypoactivity compared to their young counterparts. Evaluation of the time course of activity revealed that the young animals had a cyclical pattern of activity during the 12-hour testing period with clear peaks at 2-4 hours after the initiation of testing and at 8- to 10-hour intervals thereafter. In contrast, the aged animals exhibited a blunted initial activity peak. During the remainder of the test period the aged animals activity was stable with no further peaks in activity. Compared to the young animals the aged animals also (a) remained suspended from a horizontal wire for less time, (b) were unable to descend a wooden pole covered with wire mesh in a coordinated manner, (c) fell more rapidly from a rotating rod and (d) were unable to maintain their balance on a series of wooden beams with either a square or rounded top of varying widths. Histological analysis demonstrated that there was no reduction in the number, area, or length of tyrosine hydroxylase-immunoreactive neurons within the A8, A9, or A10 region of the aged animals. Neurochemical analysis revealed that while DA and HVA levels were not decreased in the aged rats, DOPAC levels, as well as the ratios of DA/DOPAC and DA/HVA, were decreased. These results indicate that neurochemical but not morphological changes within the nigrostriatal dopaminergic system underlie the deficits in motor behavior observed in aged rats.


Asunto(s)
Envejecimiento/fisiología , Cuerpo Estriado/química , Dopamina/fisiología , Actividad Motora/fisiología , Neuronas/química , Sustancia Negra/química , Animales , Cuerpo Estriado/citología , Oscuridad , Masculino , Neuronas/ultraestructura , Ratas , Ratas Sprague-Dawley , Sustancia Negra/citología
16.
Acad Med ; 73(1): 101-2, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9447211

RESUMEN

PURPOSE: To determine whether there is a difference between the performances of women and men students in the study of obstetrics and gynecology. METHOD: 127 students in the classes of 1996 and 1997 at the UMDNJ-School of Osteopathic Medicine studied obstetrics and gynecology as part of a four-week module on human reproduction in the fall of their second year. The module was followed by an 80-question multiple-choice examination. In their third year, the students rotated through a six-week clinical clerkship, during which they were scored on many aspects of their work, including relationships with patients. The present study examined by gender the students' overall clerkship scores, their ability to relate to patients, and their performances on the multiple-choice examination. RESULTS: No significant difference between the scores of the women students and the men students were found for the module's multiple-choice examination or for the clerkship's score on relationships with patients. However, the women scored significantly better than the men in the clerkship's overall score. CONCLUSION: The women students clearly outperformed the men students during the clinical clerkship on obstetrics and gynecology. The reasons for this are not immediately apparent. Further investigation is necessary.


Asunto(s)
Prácticas Clínicas , Competencia Clínica , Ginecología/educación , Obstetricia/educación , Estudiantes de Medicina , Femenino , Humanos , Masculino , Factores Sexuales
17.
Public Health Rep ; 105(3): 296-307, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2113690

RESUMEN

The hospital discharge diagnoses index (DI) for newborns and the birth certificate were evaluated as sources of information about birth defects by comparing them with the same births in the case registry of the California Birth Defects Monitoring Program (CBDMP). The CBDMP is an active surveillance system; the staff visit hospitals to identify children with birth defects diagnosed in the first year of life. The study population comprised 66,481 live births to residents of five counties in the San Francisco Bay area in 1983. Of these infants, 2,543 had at least one birth defect noted on the DI, and 1,623 were in the CBDMP registry; 1,020 with defects noted on the DI were also in the CBDMP registry. For this same population, 399 infants had one or more defects noted on the birth certificate; 304 of these were also in the CBDMP registry. Reporting of birth defects on the birth certificate was poor for every condition. Reporting on the DI was most reliable for oral clefts and chromosomal defects; for these defects, the DI omitted one-third of the cases but had identified only about 10 percent false-positive (that is, unverified) cases. Major central nervous system malformations were less well reported, with about one-third of them false-positive. For all other birth defects, the DI either omitted more than half of the cases, or more than half of the cases reported were false-positive cases. These findings raise questions about the validity of analytic studies of birth defects if the data are obtained only from the DI or the birth certificate.


Asunto(s)
Certificado de Nacimiento , Anomalías Congénitas/epidemiología , Registros de Hospitales , Sistema de Registros , California , Humanos , Recién Nacido
18.
BMC Geriatr ; 1: 1, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11532199

RESUMEN

BACKGROUND: Infections pose a substantial burden to the health of older adults. In this report, we describe the proceedings of a workshop to formulate and prioritize research questions about infections in older adults using an interdisciplinary approach. METHODS: Researchers from four sectors (basic science, clinical sciences, health services and epidemiology/determinants of health) and representatives from various Canadian local, provincial, and federal stakeholder groups were invited to a two-day workshop. Five multi-disciplinary groups and stakeholders from each of three healthcare settings (long term, acute care and community) discussed research priorities for each of the settings. Five to ten research questions were identified for each setting. RESULTS: The research questions proposed ranged from risk factors and outcomes for different infections to the effect of nutrition on infection and the role of alternative and complementary medicine in treating infections. Health service issues included barriers to immunization, prolongation of hospital length of stay by infection, use of care paths for managing infections, and decision-making in determining the site of care for individuals with infections. Clinical questions included risk factor assessment for infection, the effectiveness of preventative strategies, and technology evaluation. Epidemiologic issues included the challenge of achieving a better understanding of respiratory infections in the community and determining the prevalence of colonization with multi-resistant bacteria. CONCLUSIONS: The questions are of direct relevance to researchers in a wide variety of fields. Bringing together a multi-disciplinary group of researchers to frame and prioritize research questions about aging is feasible, participants valued the opinions of people working in other areas.

19.
Can J Public Health ; 91(1): 67-72, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10765590

RESUMEN

As responsibility for health funding shifts from central to local governments, providers find themselves in decision-making roles or asked to give guidance in allocation of resources. To develop a picture of a population's health, data are needed about the effects that illness and disability have on a person's ability to function and thus on quality of life. This study assessed the validity in a Canadian city, of a Health-related Quality of Life (HRQoL) instrument developed by the US Centers for Disease Control and used in the US Behavioral Risk Factor Surveillance System. The HRQoL was administered to a random sample of 1,042 adults. The patterns of association among the HRQoL questions, and the direction of the relationships among independent variables and HRQoL were consistent with those hypothesized. The accumulating evidence for validity of the HRQoL support its use in monitoring the performance of local health initiatives in Canada.


Asunto(s)
Indicadores de Salud , Estado de Salud , Vigilancia de la Población/métodos , Calidad de Vida , Encuestas y Cuestionarios/normas , Actividades Cotidianas , Adolescente , Adulto , Anciano , Centers for Disease Control and Prevention, U.S. , Femenino , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Ontario/epidemiología , Reproducibilidad de los Resultados , Estados Unidos , Salud Urbana
20.
Can J Public Health ; 92(2): 117-20, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11338149

RESUMEN

OBJECTIVE: To identify risk factors for falls and injuries among seniors living in a long-term care facility. METHOD: Case-control study of 335 residents living at St. Joseph's Villa, Dundas, Ontario. Cases were defined as residents who fell between July 1, 1996 and June 30, 1997; controls were those who did not fall. To identify risk factors for injury, cases were defined as those with completed incident injury forms and controls as those without. RESULTS: The most important risk factors for falls included: having fallen in the past three months; residing in a secured unit; living in the facility for two or more years; having the potential to cause injury to others; and having an illness, disease or behaviour that may cause a fall. The most important risk factor for injury among those who fell was altered mental state. CONCLUSION: The risk factors identified may be helpful to those planning falls prevention initiatives within long-term care settings.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Instituciones de Cuidados Especializados de Enfermería/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Heridas y Lesiones/etiología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Confusión/complicaciones , Femenino , Evaluación Geriátrica , Humanos , Modelos Logísticos , Masculino , Ontario/epidemiología , Medición de Riesgo , Factores de Riesgo , Gestión de Riesgos
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