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1.
Cerebellum ; 23(2): 341-354, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36802021

RESUMEN

Impairment of hand motor function is a frequent consequence after a stroke and strongly determines the ability to regain a self-determined life. An influential research strategy for improving motor deficits is the combined application of behavioral training and non-invasive brain stimulation of the motor cortex (M1). However, a convincing clinical translation of the present stimulation strategies has not been achieved yet. One alternative and innovative approach is to target the functionally relevant brain network-based architecture, e.g., the dynamic interactions within the cortico-cerebellar system during learning. Here, we tested a sequential multifocal stimulation strategy targeting the cortico-cerebellar loop. Anodal transcranial direct current stimulation (tDCS) was applied simultaneously to a hand-based motor training in N = 11 chronic stroke survivors during four training sessions on two consecutive days. The tested conditions were: sequential multifocal (M1-cerebellum (CB)-M1-CB) vs. monofocal control stimulation (M1-sham-M1-sham). Additionally, skill retention was assessed 1 and 10 days after the training phase. Paired-pulse transcranial magnetic stimulation data were recorded to characterize stimulation response determining features. The application of CB-tDCS boosted motor behavior in the early training phase in comparison to the control condition. No faciliatory effects on the late training phase or skill retention were detected. Stimulation response variability was related to the magnitude of baseline motor ability and short intracortical inhibition (SICI). The present findings suggest a learning phase-specific role of the cerebellar cortex during the acquisition of a motor skill in stroke and that personalized stimulation strategies encompassing several nodes of the underlying brain network should be considered.


Asunto(s)
Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Humanos , Destreza Motora/fisiología , Mano , Accidente Cerebrovascular/terapia , Cerebelo/fisiología
2.
BMC Anesthesiol ; 24(1): 156, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654164

RESUMEN

INTRODUCTION: There is a sizable niche for a minimally invasive analgesic technique that could facilitate ambulatory video-assisted thoracoscopic surgery (VATS). Our study aimed to determine the analgesic potential of a single-shot erector spinae plane (ESP) block for VATS. The primary objective was the total hydromorphone consumption with patient-controlled analgesia (PCA) 24 h after surgery. METHODS: We conducted a randomized, controlled, double-blind study with patients scheduled for VATS in two major university-affiliated hospital centres. We randomized 52 patients into two groups: a single-shot ESP block using bupivacaine or an ESP block with normal saline (control). We administered a preoperative and postoperative (24 h) quality of recovery (QoR-15) questionnaire and assessed postoperative pain using a verbal numerical rating scale (VNRS) score. We evaluated the total standardized intraoperative fentanyl administration, total postoperative hydromorphone consumption (PCA; primary endpoint), and the incidence of adverse effects. RESULTS: There was no difference in the primary objective, hydromorphone consumption at 24 h (7.6 (4.4) mg for the Bupivacaine group versus 8.1 (4.2) mg for the Control group). Secondary objectives and incidence of adverse events were not different between the two groups at any time during the first 24 h following surgery. CONCLUSION: Our multi-centre randomized, controlled, double-blinded study found no advantage of an ESP block over placebo for VATS for opioid consumption, pain, or QoR-15 scores. Further studies are ongoing to establish the benefits of using a denser block (single-shot paravertebral with a continuous ESP block), which may provide a better quality of analgesia.


Asunto(s)
Bloqueo Nervioso , Dolor Postoperatorio , Cirugía Torácica Asistida por Video , Humanos , Método Doble Ciego , Cirugía Torácica Asistida por Video/métodos , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/tratamiento farmacológico , Masculino , Bloqueo Nervioso/métodos , Femenino , Persona de Mediana Edad , Analgesia Controlada por el Paciente/métodos , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Anciano , Bupivacaína/administración & dosificación , Anestésicos Locales/administración & dosificación , Músculos Paraespinales , Hidromorfona/administración & dosificación , Adulto
3.
Perfusion ; 30(4): 302-4, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25106413

RESUMEN

Electrical storm refers to a state of cardiac electrical instability characterized by multiple episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) within a relatively short period of time and is associated with increased mortality and morbidity. The management of electrical storm involves a variety of strategies, including sedation, anti-arrhythmic and electrolyte replacement as well as revascularization and electrical ablation. However, the management strategy in patients with refractory storm is less clear and may require more invasive approaches. We present a case of severe ventricular tachycardia storm refractory to conservative management that was managed with a HeartMate II left ventricular assist device.


Asunto(s)
Corazón Auxiliar , Taquicardia Ventricular/fisiopatología , Taquicardia Ventricular/cirugía , Fibrilación Ventricular/fisiopatología , Fibrilación Ventricular/cirugía , Humanos , Masculino , Persona de Mediana Edad
4.
Eur Cell Mater ; 24: 175-95; discussion 195-6, 2012 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-22972509

RESUMEN

Biomaterial-guided regeneration represents a novel approach for the treatment of myopathies. Revascularisation and the intramuscular extracellular matrix are important factors in stimulating myogenesis and regenerating muscle damaged by ischaemia. In this study, we used an injectable collagen matrix, enhanced with sialyl LewisX (sLeX), to guide skeletal muscle differentiation and regeneration. The elastic properties of collagen and sLeX-collagen matrices were similar to those of skeletal muscle, and culture of pluripotent mESCs on the matrices promoted their differentiation into myocyte-like cells expressing Pax3, MHC3, myogenin and Myf5. The regenerative properties of matrices were evaluated in ischaemic mouse hind-limbs. Treatment with the sLeX-matrix augmented the production of myogenic-mediated factors insulin-like growth factor (IGF)-1, and IGF binding protein-2 and -5 after 3 days. This was followed by muscle regeneration, including a greater number of regenerating myofibres and increased transcription of Six1, M-cadherin, myogenin and Myf5 after 10 days. Simultaneously, the sLeX-matrix promoted increased mobilisation and engraftment of bone marrow-derived progenitor cells, the development of larger arterioles and the restoration of tissue perfusion. Both matrix treatments tended to reduce maximal forces of ischaemic solei muscles, but sLeX-matrix lessened this loss of force and also prevented muscle fatigue. Only sLeX-matrix treatment improved mobility of mice on a treadmill. Together, these results suggest a novel approach for regenerative myogenesis, whereby treatment only with a matrix, which possesses an inherent ability to guide myogenic differentiation of pluripotent stem cells, can enhance the endogenous vascular and myogenic regeneration of skeletal muscle, thus holding promise for future clinical use.


Asunto(s)
Matriz Extracelular/trasplante , Desarrollo de Músculos , Músculo Esquelético/fisiología , Regeneración , Animales , Materiales Biocompatibles/química , Cadherinas/genética , Línea Celular , Colágeno/química , Células Madre Embrionarias/citología , Matriz Extracelular/química , Femenino , Expresión Génica , Proteínas de Homeodominio/genética , Factor I del Crecimiento Similar a la Insulina/genética , Isquemia/patología , Complejo Mayor de Histocompatibilidad , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/metabolismo , Factor 5 Regulador Miogénico/genética , Miogenina/genética , Oligosacáridos/química , Factor de Transcripción PAX3 , Factores de Transcripción Paired Box/genética , Antígeno Sialil Lewis X
5.
Z Naturforsch C J Biosci ; 67(11-12): 557-64, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23413749

RESUMEN

4-(alpha-L-Rhamnosyloxy)benzyl isothiocyanate (1) and 4-(4'-O-acetyl-alpha-L-rhamnosyloxy)-benzyl isothiocyanate (2) isolated from Moringa oleifera seeds were screened for their antibacterial activities against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, and Pseudomonas aeruginosa, and for their antifungal activities against Candida albicans, Trichophyton rubrum, and Epidermophyton floccosum using the disk diffusion method. Isothiocyanates 1 and 2 were found active at the lowest inhibitory concentration of 1 mg/ml against all Gram-positive bacteria tested (S. aureus, S. epidermidis, B. subtilis) and against the dermatophytic fungi E. floccosum and T. rubrum. Statistically significant differences were found between the mean inhibition zones (IZ) of 1 and 2 and the standard drugs, ofloxacin and clotrimazole. The minimum inhibitory concentration (MIC) values confirmed the good antimicrobial activity of 1 and 2 against S. aureus, good to moderate activity against S. epidermidis, moderate activity against B. subtilis, and weak activity against E. floccosum and T. rubrum. The in vitro bactericidal effect of 1 and 2 against the Gram-positive bacterial strains tested is suggested by MBC:MIC ratios of 2:1.


Asunto(s)
Antiinfecciosos/farmacología , Isotiocianatos/farmacología , Moringa oleifera/embriología , Semillas/química , Antiinfecciosos/aislamiento & purificación , Isotiocianatos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana
6.
Nat Cell Biol ; 24(9): 1350-1363, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36075976

RESUMEN

Coordinated changes of cellular plasticity and identity are critical for pluripotent reprogramming and oncogenic transformation. However, the sequences of events that orchestrate these intermingled modifications have never been comparatively dissected. Here, we deconvolute the cellular trajectories of reprogramming (via Oct4/Sox2/Klf4/c-Myc) and transformation (via Ras/c-Myc) at the single-cell resolution and reveal how the two processes intersect before they bifurcate. This approach led us to identify the transcription factor Bcl11b as a broad-range regulator of cell fate changes, as well as a pertinent marker to capture early cellular intermediates that emerge simultaneously during reprogramming and transformation. Multiomics characterization of these intermediates unveiled a c-Myc/Atoh8/Sfrp1 regulatory axis that constrains reprogramming, transformation and transdifferentiation. Mechanistically, we found that Atoh8 restrains cellular plasticity, independent of cellular identity, by binding a specific enhancer network. This study provides insights into the partitioned control of cellular plasticity and identity for both regenerative and cancer biology.


Asunto(s)
Reprogramación Celular , Células Madre Pluripotentes Inducidas , Plasticidad de la Célula/genética , Reprogramación Celular/genética , Células Madre Pluripotentes Inducidas/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo
7.
Eur Cell Mater ; 22: 109-23, 2011 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-21892805

RESUMEN

Although many regenerative cell therapies are being developed to replace or regenerate ischaemic muscle, the lack of vasculature and poor persistence of the therapeutic cells represent major limiting factors to successful tissue restoration. In response to ischaemia, stromal cell-derived factor-1 (SDF-1) is up-regulated by the affected tissue to stimulate stem cell-mediated regenerative responses. Therefore, we encapsulated SDF-1 into alginate microspheres and further incorporated these into an injectable collagen-based matrix in order to improve local delivery. Microsphere-matrix impregnation reduced the time for matrix thermogelation, and also increased the viscosity reached. This double-incorporation prolonged the release of SDF-1, which maintained adhesive and migratory bioactivity, attributed to chemotaxis in response to SDF-1. In vivo, treatment of ischaemic hindlimb muscle with microsphere-matrix led to increased mobilisation of bone marrow-derived progenitor cells, and also improved recruitment of angiogenic cells expressing the SDF-1 receptor (CXCR4) from bone marrow and local tissues. Both matrix and SDF-1-releasing matrix were successful at restoring perfusion, but SDF-1 treatment appeared to play an earlier role, as evidenced by arterioles that are phenotypically older and by increased angiogenic cytokine production, stimulating the generation of a qualitative microenvironment for a rapid and therefore more efficient regeneration. These results support the release of implanted SDF-1 as a promising method for enhancing progenitor cell responses and restoring perfusion to ischaemic tissues via neovascularisation.


Asunto(s)
Quimiocina CXCL12/farmacología , Sistemas de Liberación de Medicamentos/métodos , Isquemia/patología , Músculo Esquelético/patología , Neovascularización Fisiológica , Células Madre/fisiología , Animales , Quimiocina CXCL12/administración & dosificación , Quimiotaxis , Colágeno , Miembro Posterior , Ratones , Microesferas , Músculo Esquelético/irrigación sanguínea
8.
EBioMedicine ; 42: 54-63, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30878598

RESUMEN

BACKGROUND: Pigs/bovines share with humans some of the antigens present on cardiac valves. Two such antigens are: the major xenogenic Ag, "Gal" present in all pig/bovine very close to human B-antigen of ABO-blood-group system; the minor Ag, pig histo-blood-group AH-antigen identical to human AH-antigen and present by some animals. We hypothesize that these antigens may modify the immunogenicity of the bioprosthesis and also its longevity. ABO distribution may vary between patients with low (<6 years) and high (≥15 years) bioprostheses longevity. METHODS: Single-centre registry study (Paris, France) including all degenerative porcine bioprostheses (mostly Carpentier-Edwards 2nd/3rd generation heart valves) explanted between 1985 and 1998 and some bovine bioprostheses. For period 1998-2014, all porcine bioprostheses with longevity ≥13 years (follow-up ≥29 years). Important predictive factors for bioprosthesis longevity: number, site of implantation, age were collected. Blood group and other variables were entered into an ordinal logistic regression analysis model predicting valve longevity, categorized as low (<6 years), medium (6-14.9 years), and high (≥15 years). FINDINGS: Longevity and ABO-blood group were obtained for 483 explanted porcine bioprostheses. Mean longevity was 10.2 ±â€¯3.9 years [0-28] and significantly higher for A-patients than others (P = 0.009). Using multivariate analysis, group A was a strong predictive factor of longevity (OR 2.09; P < 0.001). For the 64 explanted bovine bioprosthesis with low/medium longevity, the association, with A-group was even more significant. INTERPRETATION: Patients of A-group but not B have a higher longevity of their bioprostheses. Future graft-host phenotyping and matching may give rise to a new generation of long-lasting bioprosthesis for implantation in humans, especially for the younger population. FUND: None.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Implantación de Prótesis de Válvulas Cardíacas , Tasa de Supervivencia , Receptores de Trasplantes , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Bovinos , Niño , Femenino , Francia/epidemiología , Encuestas Epidemiológicas , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Longevidad , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Pronóstico , Sistema de Registros , Porcinos , Adulto Joven
9.
Eur J Clin Nutr ; 62(2): 238-46, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17375116

RESUMEN

OBJECTIVE: To compare the odds of anaemia in overweight and obese (OVWT) (body mass index (BMI) > or =25) versus non-overweight (non-OVWT) (BMI<25) women in three countries at different stages of the nutrition transition. DESIGN: Analysis of cross-sectional data. SETTING: Nationally representative data from Mexico (1998 National Nutrition Survey), Peru and Egypt (2000 Demographic and Health Surveys) were analyzed. SUBJECTS: Data from non-pregnant women ages 18-49 years were used. ANALYSIS: Logistic regression was used to test whether the odds of anaemia differed by BMI category, controlling for sociodemographic factors. RESULTS: More than half of the women were OVWT in all three countries and the prevalence of OVWT reached 77% in Egypt. Anaemia prevalence was similar across countries (28, 31 and 23% in Egypt, Peru and Mexico respectively). In Egypt, OVWT women had significantly lower odds of anaemia than non-OVWT women (OR=0.78, 95% CI: 0.68, 0.90). Similar results were found in Peru, but the difference was smaller in magnitude (OR=0.83, 95% CI: 0.71, 0.96). In Mexico, there were no differences in the odds of anaemia by BMI group. CONCLUSIONS: These findings show that the iron needs of OVWT women in developing countries are not necessarily being met. The intakes of other micronutrients might also be insufficient. Diet quality remains an important issue even among women with sufficient energy intakes.


Asunto(s)
Anemia Ferropénica/epidemiología , Dieta/normas , Hierro de la Dieta/administración & dosificación , Sobrepeso/epidemiología , Adolescente , Adulto , Anemia Ferropénica/sangre , Índice de Masa Corporal , Estudios Transversales , Escolaridad , Egipto/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Modelos Logísticos , México/epidemiología , Micronutrientes/administración & dosificación , Micronutrientes/deficiencia , Persona de Mediana Edad , Encuestas Nutricionales , Valor Nutritivo , Oportunidad Relativa , Sobrepeso/sangre , Perú/epidemiología , Clase Social
10.
Int J Artif Organs ; 29(12): 1148-57, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17219355

RESUMEN

One of the aims of tissue engineering is to be able to develop multi-tissue organs in the future. This requires the optimization of conditions for the differentiation of multiple cell types and maintenance of the differentiated phenotype within complex engineered tissues. The goal of this study was to develop prototype tissue engineered matrices to support the simultaneous growth of different cell types with a particular focus on the angiogenic process. We examined two different matrix compositions for the promotion of blood vessel and tube formation. A fibrin-based matrix with the addition of a combination of growth factors supported vascular growth and the invasion of inflammatory cells. Using this fibrin matrix, in combination with a collagen-based hydrogel, a simple in vitro model of the cornea with adjacent sclera was developed that was complete with innervation and vascular structures. In addition, we showed that collagen-based matrices were effective in delivering mononuclear endothelial progenitor cells to ischemic tissue in vivo, and allowing these cells to incorporate into vascular structures. It is anticipated that with further development, these matrices have potential for use as delivery matrices for cell transplantation and for in vitro study purposes of multiple cell types.


Asunto(s)
Córnea/irrigación sanguínea , Células Endoteliales/fisiología , Matriz Extracelular , Esclerótica/irrigación sanguínea , Células Madre/fisiología , Ingeniería de Tejidos/métodos , Acrilamidas , Acrilatos , Animales , Técnicas de Cocultivo , Colágeno , Córnea/inervación , Fibrinógeno , Miembro Posterior/irrigación sanguínea , Humanos , Isquemia/terapia , Neovascularización Fisiológica/fisiología , Polímeros , Ratas , Ratas Desnudas , Esclerótica/inervación , Trasplante de Células Madre , Trombina
11.
12.
Clin Pharmacol Ther ; 47(5): 618-28, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2111750

RESUMEN

Thirteen patients with cystic fibrosis and 12 healthy control volunteers received a single oral 800 mg dose of fleroxacin and 800 mg every day for 5 days. Interstitial fluid penetration was studied by the suction-induced blister technique. Fleroxacin and its two major metabolites, N-demethyl and N-oxide, were analyzed in plasma and urine by HPLC. Single-dose absorption parameters (absorption rate constant, normalized peak plasma drug concentration, and time to reach peak concentration) and total urinary excretion indicated that fleroxacin was absorbed more slowly and more completely in patients with cystic fibrosis than in control subjects. Fleroxacin volume of distribution tended to be smaller in patients with cystic fibrosis and it reached statistical significance after a single dose when normalization for lean body mass was applied. When normalized for lean body mass, the formation clearance of N-demethyl fleroxacin and N-oxide fleroxacin was significantly greater in patients with cystic fibrosis than in control subjects (p less than 0.05). These data concur with those of others showing an induction of drug-metabolizing enzymes in cystic fibrosis. Renal clearances of fleroxacin and its metabolites were significantly increased in cystic fibrosis (p less than 0.05), and this seems to be explained by a decreased tubular reabsorption of these compounds. The differences seen in the pharmacokinetics of fleroxacin in cystic fibrosis support the theories of generalized induction of drug metabolism and of a defective renal tubular reabsorptive process of drugs in cystic fibrosis.


Asunto(s)
Antiinfecciosos/farmacocinética , Ciprofloxacina/análogos & derivados , Fibrosis Quística/metabolismo , Administración Oral , Adolescente , Adulto , Antiinfecciosos/administración & dosificación , Antiinfecciosos/efectos adversos , Ciprofloxacina/administración & dosificación , Ciprofloxacina/efectos adversos , Ciprofloxacina/farmacocinética , Esquema de Medicación , Espacio Extracelular/metabolismo , Femenino , Fleroxacino , Humanos , Masculino , Valores de Referencia
13.
Am J Clin Nutr ; 68(2 Suppl): 488S-494S, 1998 08.
Artículo en Inglés | MEDLINE | ID: mdl-9701166

RESUMEN

Because trace minerals are important not only for human nutrition but for plant nutrition as well, plant breeding holds great promise for making a significant, sustainable, low-cost contribution to the reduction of micronutrient deficiencies in humans. It may also have important spinoff effects for increasing farm productivity in developing countries in an environmentally beneficial way. This article describes ongoing plant breeding research that could increase the intake of bioavailable zinc from food staple crops in vulnerable populations in developing countries. The 3 most promising plant breeding strategies toward this goal are as follows: 1) increasing the concentration of zinc, 2) reducing the amount of phytic acid (a strong inhibitor of zinc absorption), and 3) raising the concentrations of sulfur-containing amino acids (thought to promote zinc absorption) in the plant. The agronomic advantages and disadvantages as well as the potential benefits and limitations of each approach for human nutrition are described. Research is currently underway to identify the optimal combination of these approaches that will maximize the effect on human zinc nutrition.


Asunto(s)
Plantas/química , Zinc/deficiencia , Disponibilidad Biológica , Cruzamiento , Suplementos Dietéticos , Humanos , Ácido Fítico/análisis , Zinc/administración & dosificación , Zinc/metabolismo
14.
Am J Clin Nutr ; 63(5): 671-7, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8615348

RESUMEN

The risk approach has been promoted to improve screening for nutrition interventions on the premise that indicators of risk also predict greater response to interventions. This study tested whether the determinants of the risk of poor growth (eg, low length-for-age) at 36 mo of age were the same as the determinants of differential benefit from food supplementation. The sample included 460 Guatemalan children who were exposed to either a high-energy, high-protein drink (atole) or a low-energy, no-protein drink (fresco) during their first 36 mo of life [INCAP (Institute of Nutrition of Central America and Panama) supplementation trial]. Low maternal stature, poor socioeconomic status, inadequate home diet, high diarrhea rates, and low anthropometry scores at 3 or 6 mo were all determinants of the risk of poor growth. Only indicators of child's thinness at 3 or 6 mo of age (low weight-for-age, weight-for-length, or midupper arm circumference) were determinants of differential benefit from supplementation. Thus, the development of screening indicators should be based on analyses of the predictors of differential benefit, not on conventional risk-factor analysis.


Asunto(s)
Fenómenos Fisiológicos Nutricionales Infantiles , Dieta/normas , Proteínas en la Dieta/administración & dosificación , Tamizaje Masivo/economía , Antropometría , Peso Corporal/fisiología , Preescolar , Análisis Costo-Beneficio , Diarrea/epidemiología , Diarrea/fisiopatología , Diarrea/prevención & control , Femenino , Alimentos Fortificados/economía , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Bienestar Materno , Factores de Riesgo , Factores Socioeconómicos
15.
Am J Clin Nutr ; 65(2): 439-44, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9022528

RESUMEN

The large within- and between-sample variability in breast milk lipid content greatly complicates the collection of representative samples in field studies. The main purpose of this study was to validate the ability of individual daytime samples to predict the 24-h lipid concentration of breast milk. We also studied maternal, child, and other factors (time of day and interval between feeds) associated with the within- and between-mother variability in milk lipid content. Fifty-two primiparous urban Guatemalan women between 1 and 4 mo postpartum were studied. Milk samples were collected during six 2-h intervals from 0600 to 1800, and throughout the night when the child breast-fed. On average, the 24-h pooled milk samples contained 4.2 +/- 0.92% (mean +/- SD) lipids and the best concordance with this value was obtained with samples collected between 0600 and 0800 (concordance correlation coefficient = 0.60, P < 0.05). None of the regression equations to predict the 24-h lipid content of breast milk based on daytime samples reached a sufficiently high predictive power to be recommended for the estimation of individual child intake. Time of day and time elapsed since the last feeding were significant determinants of diurnal variations in milk lipid content, whereas between-mother variability was explained by maternal weight (P = 0.05) and body mass index (P < 0.05). For the collection of milk samples in surveys and pre-post studies, we recommend standardization of time of day and interval between feeds.


Asunto(s)
Lípidos/análisis , Leche Humana/metabolismo , Adulto , Ritmo Circadiano , Ayuno/metabolismo , Femenino , Guatemala , Humanos , Análisis de Regresión , Reproducibilidad de los Resultados , Población Urbana
16.
Am J Clin Nutr ; 65(4 Suppl): 1159S-1165S, 1997 04.
Artículo en Inglés | MEDLINE | ID: mdl-9094914

RESUMEN

Several countries, including Mexico, are experiencing changes in health patterns that are characterized by an increase in the prevalence of chronic diseases and changes in the principal causes of death, coexisting with deficiencies in the intake of energy and micronutrients, particularly in children. Several factors may explain these changes, including dietary habits. To evaluate food consumption in a population undergoing a health transition, a food-frequency questionnaire was developed, validated, and used to study the dietary determinants of chronic diseases in Mexico. Nutrient deficiency and the relation between maternal child-feeding behaviors and dietary intake by the child were evaluated with use of 24-h recalls, food-frequency methods. and estimation of food intake by observation. The observation method was extremely useful for studies in rural areas.


Asunto(s)
Dieta , Evaluación Nutricional , Adulto , América Central , Niño , Registros de Dieta , Humanos , México , Trastornos Nutricionales/epidemiología , Encuestas y Cuestionarios
17.
Am J Clin Nutr ; 69(6): 1243-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10357746

RESUMEN

BACKGROUND: Previous research has suggested that there may be significant within-subject variability, both site-to-site and over time, in hemoglobin concentrations in capillary blood. OBJECTIVE: This study examined the reliability of the portable hemoglobinometer (PHM) system with use of capillary blood and the implications of errors of the magnitude found for the classification of anemia status in individuals and population groups. The precision and accuracy of the method with use of venous blood were also tested. DESIGN: Three empirical data sets were used to measure reliability, precision, and accuracy of the PHM system [2 from Honduras (n = 87 and 141); 1 from Bangladesh (n = 73)]. Simulation data were used to assess the implications of errors for screening individuals for anemia and to estimate anemia prevalence. RESULTS: High within-subject variability (unreliability) was identified when capillary blood from the left hand was compared with that from the right hand (CV: 6.3%) and when measurements were taken on 4 consecutive days (CV: 7.0%). Reliability was only 69% and 50%, respectively. Precision and accuracy, however, were very high (concordance coefficients of 0.99 and 0.98 and CV < 1%). CONCLUSIONS: The simulation data showed that errors of the magnitude found due to unreliability can lead to misclassification of anemia status in individuals and small biases in anemia prevalence estimates. We recommend replicate sampling to reduce the influence of unreliability in the use of the PHM system with capillary blood.


Asunto(s)
Anemia/diagnóstico , Hemoglobinas/análisis , Adolescente , Adulto , Anemia/sangre , Anemia/clasificación , Anemia/epidemiología , Bangladesh/epidemiología , Sesgo , Análisis Químico de la Sangre , Capilares , Niño , Falla de Equipo , Femenino , Hemoglobinometría/instrumentación , Honduras/epidemiología , Humanos , Lactante , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados
18.
Am J Clin Nutr ; 72(6): 1516-22, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11101480

RESUMEN

BACKGROUND: Zinc deficiency is prevalent in children in developing countries. Supplemental zinc provides therapeutic benefits in diarrhea. OBJECTIVE: We sought to measure the effect of supplemental zinc given with oral rehydration therapy during recovery from acute or persistent diarrhea. DESIGN: We conducted pooled analyses including all available published and unpublished randomized controlled trials of the effects of supplementary oral zinc in children aged <5 y with acute or persistent diarrhea. We used Cox survival regression analysis to evaluate the overall effect of zinc on continuation of diarrhea and possible differential effects in subgroups divided by sex, age, weight-for-height, and initial plasma zinc concentration. Dichotomous outcomes were analyzed by logistic regression. To assess the effects of excluding studies without original data from the pooled analyses, effect-size was estimated for all studies by using random-effects models. RESULTS: Zinc-supplemented children had a 15% lower probability of continuing diarrhea on a given day (95% CI: 5%, 24%) in the acute-diarrhea trials and a 24% lower probability of continuing diarrhea (95% CI: 9%, 37%) and a 42% lower rate of treatment failure or death (95% CI: 10%, 63%) in the persistent-diarrhea trials. In none of the subgroup analyses were the 2 subgroups of each pair significantly different from each other; however, in persistent diarrhea there tended to be a greater effect in subjects aged <12 mo, who were male, or who had wasting or lower baseline plasma zinc concentrations. CONCLUSION: Zinc supplementation reduces the duration and severity of acute and persistent diarrhea.


Asunto(s)
Países en Desarrollo , Diarrea/tratamiento farmacológico , Zinc , Enfermedad Aguda , Administración Oral , Preescolar , Femenino , Fluidoterapia , Humanos , Lactante , Modelos Logísticos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Zinc/administración & dosificación , Zinc/sangre , Zinc/deficiencia , Zinc/uso terapéutico
19.
Am J Cardiol ; 63(5): 277-81, 1989 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-2521537

RESUMEN

Among 868 patients with successful percutaneous transluminal coronary angioplasty (PTCA), 437 were restudied angiographically and had a provocative test with ergonovine during coronary angiography performed before and 6 months after the procedure. The relation between provoked coronary artery spasm and restenosis was studied and 4 groups of patients were analyzed. Those in group 1 (n = 63) had spasm before and after PTCA and their rate of restenosis was high (55%), especially when spasm after PTCA was observed on the dilated coronary segment (restenosis rate 58%). Patients in group 2 (n = 78) had spasm before PTCA but without abnormal vasoconstriction at 6 months and their incidence of restenosis was 19%. Sixty-one patients in group 3 had no spasm before PTCA but developed spasm at restudy. The rate of restenosis was high (38%) in this group, especially when the spasm after PTCA was located on the dilated segment (43%). In group 4 (n = 235), patients had no spasm before or after PTCA and the restenosis rate was 20%. Thus, the presence of coronary artery spasm on the dilated coronary segment, 6 months after a successful PTCA, is frequently accompanied (43% in group 3 and 58% in group 1) by restenosis.


Asunto(s)
Angioplastia de Balón , Angiografía Coronaria , Vasoespasmo Coronario/terapia , Sistema Vasomotor/fisiopatología , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/fisiopatología , Vasoespasmo Coronario/diagnóstico por imagen , Vasoespasmo Coronario/fisiopatología , Vasos Coronarios/fisiopatología , Ergonovina , Humanos , Vasodilatación
20.
Chest ; 115(5): 1248-53, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10334135

RESUMEN

STUDY OBJECTIVE: To improve the respiratory isolation policy for patients with suspected pulmonary tuberculosis (TB). DESIGN: Prospective, descriptive, French multicenter study. SETTING: Emergence of nosocomial outbreaks of TB. PATIENTS: All consecutive patients admitted with suspicion of pulmonary TB. MEASUREMENTS AND RESULTS: Medical history, social factors, symptoms, and chest radiograph (CXR) pattern (symptoms and CXR both scored as typical of pulmonary TB, compatible, negative, or atypical) were obtained on admission. Serial morning sputa were collected. Of the 211 patients, 47 (22.3%) had culture-proven pulmonary TB, including 31 (14.7%) with a positive smear. Mean age was 46.2 years; 52 patients were HIV positive (24.6%). The sensitivity of the respiratory isolation policy was 71.4%, specificity was 51.7%, negative predictive value (NPV) was 88.2%, and positive predictive value (PPV) was 26.3%. On univariate analysis, predictive factors of culture-proven pulmonary TB were CXR (p < 0.00001), symptoms (p = 0.0004), age (mean, 40.8 years for TB patients vs 47.5 years for non-TB patients; p = 0.04), absence of HIV infection (89.4% vs 71.3%; p = 0.01), immigrant status (72% vs 55%; p = 0.03), and bacillus Calmette-Guérin status (p = 0.025). On multivariate analysis, CXR pattern (p < 0.00001), HIV infection (p = 0.002), and symptoms (p = 0.009) remained independently predictive. Based on these data, a model was proposed using a receiver operating characteristics curve. In the derivation cohort, the sensitivity and NPV of the model in detecting smear-positive pulmonary TB would have been 100%. The specificity and PPV would have been 48.4% and 25%, respectively. The model performed less well when evaluated on two retrospective groups, but its sensitivity remained above that of the current respiratory isolation policy (91.1% and 82.4% for the retrospective groups vs 71.1% for the current policy). CONCLUSIONS: Improved interpretation of clinical and radiologic data available on patient admission could improve adequacy of respiratory isolation. A prediction model is proposed.


Asunto(s)
Tuberculosis Pulmonar/diagnóstico , Vacuna BCG , Infección Hospitalaria/prevención & control , Emigración e Inmigración , Femenino , Francia , Seropositividad para VIH/complicaciones , Personas con Mala Vivienda , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Aislamiento de Pacientes , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Radiografía Torácica , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Esputo/microbiología , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/diagnóstico por imagen , Tuberculosis Pulmonar/prevención & control
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