RESUMEN
The centrosome is the primary microtubule-organizing center (MTOC) of most animal cells; however, this organelle is absent during early mammalian development. Therefore, the mechanism by which the mammalian embryo organizes its microtubules (MTs) is unclear. We visualize MT bridges connecting pairs of cells and show that the cytokinetic bridge does not undergo stereotypical abscission after cell division. Instead, it serves as scaffold for the accumulation of the MT minus-end-stabilizing protein CAMSAP3 throughout interphase, thereby transforming this structure into a noncentrosomal MTOC. Transport of the cell adhesion molecule E-cadherin to the membrane is coordinated by this MTOC and is required to form the pluripotent inner mass. Our study reveals a noncentrosomal form of MT organization that directs intracellular transport and is essential for mammalian development.
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Embrión de Mamíferos/metabolismo , Centro Organizador de los Microtúbulos/metabolismo , Animales , Transporte Biológico , Cadherinas/metabolismo , División Celular , Centrosoma/metabolismo , Embrión de Mamíferos/citología , Desarrollo Embrionario , Interfase , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismoRESUMEN
Compaction is a critical first morphological event in the preimplantation development of the mammalian embryo. Characterized by the transformation of the embryo from a loose cluster of spherical cells into a tightly packed mass, compaction is a key step in the establishment of the first tissue-like structures of the embryo. Although early investigation of the mechanisms driving compaction implicated changes in cell-cell adhesion, recent work has identified essential roles for cortical tension and a compaction-specific class of filopodia. During the transition from 8 to 16 cells, as the embryo is compacting, it must also make fundamental decisions regarding cell position, polarity, and fate. Understanding how these and other processes are integrated with compaction requires further investigation. Emerging imaging-based techniques that enable quantitative analysis from the level of cell-cell interactions down to the level of individual regulatory molecules will provide a greater understanding of how compaction shapes the early mammalian embryo.
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Embrión de Mamíferos/citología , Desarrollo Embrionario , Animales , División Celular , Linaje de la Célula , Forma de la Célula , RatonesRESUMEN
It was hypothesized that normoxic 30% nitrous oxide (N2O) would suppress and hyperthermia would increase exercise ventilation during short duration, high intensity exercise. Thirteen males (24.2±0.8y; mean±SE), of normal physique (BMI, 23.8±1.0kgm(-2)), performed 4 separate 30s Wingate tests on a cycle ergometer. Exercise ventilation and its components, as well as mean skin and esophageal temperature (TES), were assessed in 2 way experimental design with factors of Thermal State (Normothermia or Hyperthermia) and Gas Type (Air or 30% Normomoxic N2O). In the 2 hyperthermic tests TES was elevated to â¼38.5°C in a 40°C bath. The main results indicated a significant interaction (F=7.14, P=0.02) between Gas Type and Thermal state for the exercise-induced increase in ventilation (ΔVËE). During both the normothermia and hyperthermia conditions with AIR breathing, the exercise ΔVËE was â¼80Lmin(-1) and it was significantly decreased to 73.1±24.1Lmin(-1) in the normothermia condition with N2O breathing relative to that of 92.0±25.0Lmin(-1) in the hyperthermia condition with N2O breathing. In conclusion, normoxic N2O breathing suppressed high intensity exercise ventilation during normothermia relative to that during hyperthermia on account of decreases in the tidal volume and this led CO2 retention.
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Regulación de la Temperatura Corporal/fisiología , Ejercicio Físico/fisiología , Respiración , Adulto , Ergometría , Fiebre , Humanos , Masculino , Óxido Nitroso , Consumo de Oxígeno , Volumen de Ventilación Pulmonar , Factores de Tiempo , Adulto JovenRESUMEN
For human exercise at intensities greater than approximately 70 to 85% of maximal levels of exertion, ventilation (V E) increases proportionately to core temperature (T C) following distinct T C thresholds. This suggested T C in humans could be a modulator of exercise-induced ventilation. This study tested the reproducibility of relationships between oesophageal temperature (T oes) ventilation and its components during incremental exercise. On two nonconsecutive days, at an ambient temperature of 22.1+/-0.3 degrees C and RH of 45+/-5%, seven untrained adult males of normal physique pedaled on a seated cycle ergometer in an incremental exercise protocol from rest to the point of exhaustion. In each exercise session, ventilatory equivalents for oxygen consumption (VE.VO2 (1-)) and carbon dioxide production (VE.VCO2 (1-)) plus the components of V E, tidal volume (V T) and frequency of respiration (f), were expressed as a function of T oes. Results indicated the reproducibility criteria of Bland and Altman were met for the relationships between T oes and both (VE.VO2 (1-)) and (VE.VCO2 (1-)) as well as for relationships between T oes and each of V T and f. Intraclass correlation coefficients (R) for between-trial T oes thresholds for (R=0.91, P<0.05) and (R=0.88, P<0.05) were also high and significant. In both trials, after T oes increased by approximately 0.3 degrees C, V T demonstrated a distinct plateau point at a reproducible T oes (R=0.93, P<0.05) and f demonstrated a distinct and reproducible T oes threshold (R=0.84, P<0.05). In conclusion, the results illustrate that for humans, ventilation has a significant and reproducible relationship with core temperature during incremental exercise.
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Temperatura Corporal/fisiología , Esófago/fisiología , Prueba de Esfuerzo/normas , Esfuerzo Físico/fisiología , Ventilación Pulmonar/fisiología , Adolescente , Adulto , Dióxido de Carbono/metabolismo , Prueba de Esfuerzo/métodos , Humanos , Masculino , Consumo de Oxígeno/fisiología , Reproducibilidad de los Resultados , Volumen de Ventilación Pulmonar/fisiologíaRESUMEN
Flow of nonvolatile nonaqueous phase liquid (NAPL) and aqueous phases that account for mobile, entrapped, and residual NAPL in variably saturated water-wet porous media is modeled and compared against results from detailed laboratory experiments. Residual saturation formation in the vadose zone is a process that is often ignored in multifluid flow simulators, which might cause an overestimation of the volume of NAPL that reaches the ground water. Mobile NAPL is defined as being continuous in the pore space and flows under a pressure gradient or gravitational body force. Entrapped NAPL is defined as being occluded by the aqueous phase, occurring as immobile ganglia surrounded by aqueous phase in the pore space and formed when NAPL is replaced by the aqueous phase. Residual NAPL is defined as immobile, nonwater entrapped NAPL that does not drain from the pore spaces and is conceptualized as being either continuous or discontinuous. Free NAPL comprises mobile and residual NAPL. The numerical model is formulated on mass conservation equations for oil and water, transported via NAPL and aqueous phases through variably saturated porous media. To account for phase transitions, a primary variable switching scheme is implemented for the oil-mass conservation equation over three phase conditions: (1) aqueous or aqueous-gas with dissolved oil, (2) aqueous or aqueous-gas with entrapped NAPL, and (3) aqueous or aqueous gas with free NAPL. Two laboratory-scale column experiments are modeled to verify the numerical model. Comparisons between the numerical simulations and experiments demonstrate the necessity to include the residual NAPL formation process in multifluid flow simulators.
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Modelos Teóricos , Movimientos del Agua , Contaminantes del Agua , Porosidad , Suelo , SolubilidadRESUMEN
The purpose of the study was to identify extracranial locations in which temperature changes in humans reflect those of intracranial temperature in a reliable and repeatable way. This was achieved by subjecting 14 non-anaesthetized patients after neurosurgery to face fanning while intracranial and extracranial temperatures were continuously measured. In all patients the cranium was closed and the group included both febrile and non-febrile as well as hyperthermic and normothermic patients. The patients' faces were fanned for 20-30 min, with a small fan at an air speed of 3.25 m s(-1). This gave intracranial temperature changes measured in the subdural space ( T(sd)) that were highly and significantly correlated ( r=0.91, P<0.05, n=14) with changes in tympanic temperatures ( T(ty)). A low, statistically insignificant correlation ( r=0.40, P>0.05, n=12) was found between T(sd) and oesophageal temperatures. In conclusion, intracranial temperature changes, induced by face fanning, were reliably reflected by the changes in T(ty).
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Regulación de la Temperatura Corporal/fisiología , Temperatura Corporal/fisiología , Encéfalo/fisiología , Oído Medio/fisiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Membrana TimpánicaRESUMEN
We tested the reproducibility of the heart rate variability (HRV) measurements before and after a standardized meal. Heart rate recordings were obtained in 14 healthy subjects tested in a reclining position before and after a standardized meal on two separated occasions, apart by a 1-2-week interval. We measured three components of HRV: sympathetic activity (SYMP), parasympathetic activity (PSYMP) and the ratio of SYMP/PSYMP under controlled breathing and noncontrolled breathing conditions. We observed that all components were reproducible during noncontrolled breathing condition, whereas only PSYMP was reproducible during controlled breathing condition. Our results thus indicate that HRV measurements could be a useful, noninvasive and nonexpensive method to provide SYMP and SYMP/PSYMP in feeding behavior studies when measured under noncontrolled breathing conditions. Nonetheless, using a controlled breathing condition may be relevant when assessing the effect of various interventions or drugs on parasympathetic activity.
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Frecuencia Cardíaca/fisiología , Periodo Posprandial/fisiología , Adulto , Sistema Nervioso Autónomo/fisiología , Electrocardiografía , Femenino , Humanos , Masculino , Fenómenos Fisiológicos de la Nutrición , Reproducibilidad de los Resultados , Mecánica Respiratoria/fisiologíaRESUMEN
A substantial amount of research has established that truancy is a consistent at-risk indicator of future criminality. This article studies the experiences of 178 juveniles targeted by the Truant Recovery Program, a collaborative and nonpunitive school-law enforcement effort, and considers questions regarding its impact through examination of juvenile justice and school information in the years before and after the truancy sweep. In particular, the article suggests that intensive cooperative efforts between school and police may be effective in identifying troubled youth and raises questions about appropriate school and justice system responses for children who demonstrate at-risk behavior.
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Absentismo , Delincuencia Juvenil/prevención & control , Policia/organización & administración , Instituciones Académicas/organización & administración , Control Social Formal , Adolescente , California , Niño , Conducta Cooperativa , Femenino , Humanos , Delincuencia Juvenil/legislación & jurisprudencia , Delincuencia Juvenil/psicología , Masculino , Relaciones Padres-Hijo , Evaluación de Programas y Proyectos de Salud , Carencia Psicosocial , Medición de Riesgo , Asunción de Riesgos , Factores SocioeconómicosRESUMEN
Lymphocyte trafficking in the gastrointestinal tract is primarily mediated by interactions with the mucosal addressin cell adhesion molecule 1 and its lymphocyte ligand, alpha(4)beta(7), and partly by L-selectin (L-Sel) interactions with peripheral node addressin coexpressed on some mucosal addressin cell adhesion molecule 1. We inquired whether intestinal responses in mice lacking L-Sel would be enhanced. L-Sel-deficient (L-Sel(-/-)) mice were orally immunized with either Salmonella vaccine vector or Salmonella vector-expressing colonization factor Ag I (CFA/I) from enterotoxigenic Escherichia coli. In L-Sel(-/-) mice, mucosal IgA anti-CFA/I fimbrial responses were greatly reduced, and systemic IgG2a anti-CFA/I fimbrial responses were 26-fold greater compared with C57BL/6 (L-Sel(+/+)) mice. L-Sel(-/-) Peyer's patch (PP) CD4(+) Th cells revealed IFN-gamma-dominated responses and an unprecedented absence of IL-4, whereas the expected mixed Th cell phenotype developed in L-Sel(+/+) mice. PP CD4(+) Th cell anti-Salmonella responses were nearly nonexistent in L-Sel(-/-) mice immunized with either Salmonella vaccine. Splenic CD4(+) Th cell anti-Salmonella responses were reduced but did show cytokine production in Ag restimulation assays. Increased colonization of PP and spleen was noted only with the Salmonella vector in L-Sel(-/-) mice, resulting in increased splenomegaly, suggesting that the Salmonella-CFA/I vaccine was not as infectious or that the presence of the fimbriae improved clearance, possibly because of reduced neutrophil recruitment. However, sufficient anti-Salmonella immunity was induced, because Salmonella vector-immunized L-Sel(-/-) mice showed complete protection against wild-type Salmonella challenge, unlike L-Sel(+/+) mice. This evidence shows that L-Sel is important for development of mucosal immunity, and absence of L-Sel is protective against salmonellosis.
Asunto(s)
Proteínas Fimbrias , Vectores Genéticos/administración & dosificación , Vectores Genéticos/inmunología , Selectina L/genética , Vacunas contra la Salmonella/administración & dosificación , Vacunas contra la Salmonella/inmunología , Salmonella typhimurium/genética , Salmonella typhimurium/inmunología , Administración Oral , Animales , Antígenos Bacterianos/biosíntesis , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Epítopos de Linfocito T/inmunología , Fimbrias Bacterianas/inmunología , Inmunidad Mucosa/genética , Inmunoglobulina A/biosíntesis , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infiltración Neutrófila/genética , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/microbiología , Salmonelosis Animal/genética , Salmonelosis Animal/inmunología , Salmonelosis Animal/prevención & control , Vacunas contra la Salmonella/genética , Bazo/inmunología , Bazo/microbiología , Esplenomegalia/inmunología , Esplenomegalia/microbiología , Esplenomegalia/prevención & control , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunologíaRESUMEN
Computational simulations of two-phase flow in porous media are used to investigate the feasibility of replacing a porous medium containing heterogeneities with an equivalent homogeneous medium. Simulations are performed for the case of infiltration of a dense nonaqueous phase liquid (DNAPL) in a water-saturated, heterogeneous porous medium. For two specific porous media, with periodic and rather simple heterogeneity patterns, the existence of a representative elementary volume (REV) is studied. Upscaled intrinsic permeabilities and upscaled nonlinear constitutive relationships for two-phase flow systems are numerically calculated and the effects of heterogeneities are evaluated. Upscaled capillary pressure-saturation curves for drainage are found to be distinctly different from the lower-scale curves for individual regions of heterogeneity. Irreducible water saturation for the homogenized medium is found to be much larger than the corresponding lower-scale values. Numerical simulations for both heterogeneous and homogeneous representations of the considered porous media are carried out. Although the homogenized model simulates the spreading behavior of DNAPL reasonably well, it still fails to match completely the results form the heterogeneous simulations. This seems to be due, in part, to the nonlinearities inherent to multiphase flow systems. Although we have focussed on a periodic heterogeneous medium in this study, our methodology is applicable to other forms of heterogeneous media. In particular, the procedure for identification of a REV, and associated upscaled constitutive relations, can be used for randomly heterogeneous or layered media as well.
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Agua/química , Modelos Teóricos , PresiónRESUMEN
Vaccination by anthrax protective antigen (PA)-based vaccines requires multiple immunization, underlying the need to develop more efficacious vaccines or alternative vaccination regimens. In spite of the vast use of PA-based vaccines, the definition of a marker for protective immunity is still lacking. Here we describe studies designed to help define such markers. To this end we have immunized guinea pigs by different methods and monitored the immune response and the corresponding extent of protection against a lethal challenge with anthrax spores. Active immunization was performed by a single injection using one of two methods: (i) vaccination with decreasing amounts of PA and (ii) vaccination with constant amounts of PA that had been thermally inactivated for increasing periods. In both studies a direct correlation between survival and neutralizing-antibody titer was found (r(2) = 0.92 and 0.95, respectively). Most significantly, in the two protocols a similar neutralizing-antibody titer range provided 50% protection. Furthermore, in a complementary study involving passive transfer of PA hyperimmune sera to naive animals, a similar correlation between neutralizing-antibody titers and protection was found. In all three immunization studies, neutralization titers of at least 300 were sufficient to confer protection against a dose of 40 50% lethal doses (LD(50)) of virulent anthrax spores of the Vollum strain. Such consistency in the correlation of protective immunity with anti-PA antibody titers was not observed for antibody titers determined by an enzyme-linked immunosorbent assay. Taken together, these results clearly demonstrate that neutralizing antibodies to PA constitute a major component of the protective immunity against anthrax and suggest that this parameter could be used as a surrogate marker for protection.
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Antígenos Bacterianos , Bacillus anthracis/inmunología , Toxinas Bacterianas/inmunología , Vacunas Bacterianas/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Cobayas , Sueros Inmunes/inmunología , Inmunoglobulina G/sangre , VacunaciónRESUMEN
OBJECTIVE: To compare the effect of medium chain triglycerides (MCT) vs long chain triglycerides (LCT) feeding on exogenous and endogenous oxidation of long chain saturated fatty acids (LCSFA) in women. SUBJECTS: Twelve healthy female subjects (age 19-26 y, body mass index (BMI) 17.5-28.6 kg/m2) DESIGN AND MEASUREMENTS: In a randomized cross-over design, subjects were fed weight maintenance diets providing 15%, 45% and 40% of energy as protein, carbohydrate and fat, respectively, with 80% of this fat comprising either a combination of butter and coconut oil (MCT) or beef tallow (LCT). Following 6 days of feeding, subjects were given daily oral doses of 1-(13)C labelled-myristic, -palmitic and -stearic acids for 8 days. Expired 13CO2 was used as an index of LCSFA oxidation with CO2 production assessed by respiratory gas exchange. RESULTS: No difference in exogenous LCSFA oxidation was observed as a function of diet on day 7. On day 14, greater combined cumulative fractional LCSFA oxidation (16.9 +/- 2.5%/5.5 h vs 9.1 +/- 1.2%/5.5 h, P < 0.007), net LCSFA oxidation (2956 +/- 413 mg/5.5 h vs 1669 +/- 224 mg/5.5 h, P < 0.01), and percentage dietary LCSFA contribution to total fat oxidation (16.3 +/- 2.3%/5.5 h vs 9.5 +/- 1.5%/5.5 h; P < 0.01) were observed in women fed the MCT vs LCT diet. With the MCT diet, but not the LCT diet, combined cumulative fractional LCSFA oxidation (P < 0.03), net LCSFA oxidation (P < 0.03), and percentage dietary LCSFA contribution to total fat oxidation (P < 0.02) were increased at day 14 as compared to day 7. Day 14 results indicated increased endogenous LCSFA oxidation during MCT feeding. CONCLUSION: The capacity of MCT to increase endogenous oxidation of LCSFA suggests a role for MCT in body weight control over the long term.
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Grasas de la Dieta/administración & dosificación , Ácidos Grasos/metabolismo , Triglicéridos/administración & dosificación , Triglicéridos/química , Adulto , Pruebas Respiratorias , Isótopos de Carbono , Estudios Cruzados , Femenino , Humanos , Ácido Mirístico/metabolismo , Oxidación-Reducción , Ácido Palmítico/metabolismo , Intercambio Gaseoso Pulmonar , Ácidos Esteáricos/metabolismoRESUMEN
Deadly force research typically does not distinguish between shootings by on-duty and off-duty police. This article uses Philadelphia police shooting data from two time periods (1970-1978 and 1987-1992) and a unique quasi-experimental design to examine the comparative effects upon on- and off-duty police shootings of an administrative policy that limited police shooting discretion but that did not address questions of police weapons carrying and access to firearms. The article draws important distinctions between when to shoot and carry administrative policies and considers their impact on deadly force by on- and off-duty police.
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Armas de Fuego , Política Organizacional , Policia , Violencia , Adulto , Femenino , Humanos , Masculino , PhiladelphiaRESUMEN
Voiding dysfunction is common, and patients with urge incontinence, frequency/urgency syndromes, and chronic urinary retention are challenging to treat once conservative therapies (such as pharmacologic agents, pelvic floor rehabilitation, and intermittent catheterization) have been exhausted. Sacral nerve stimulation (SNS) is a new, minimally invasive, reversible therapy for the management of refractory voiding dysfunction and provides an attractive therapeutic alternative for patients with this condition. In this review, the role of SNS in the management of voiding dysfunction is examined critically, and the efficacy, risks, and benefits of this new modality are evaluated.
RESUMEN
This study is the first report on human intracranial temperature in conscious patients during and after an upper respiratory bypass. Temperatures were measured in four subjects subdurally between the frontal lobes and cribriform plate (T(cr)) and on the vault of the skull (T(sd)). Further measurements were taken in the esophagus (T(es)) and on the tympanic membrane. Reinstitution of airflow in the upper respiratory tract under conditions of mild hyperthermia gave a rapid drop in T(cr) of 0.4-0.8 degrees C. In three patients the intracranial temperature at the basal aspect of the frontal lobes fell below T(es). Thus local selective cooling of the brain surface below that of the trunk temperature was shown to occur. Intensive breathing by the patients after extubation for a 3-min period produced a cooling at the site of T(cr) measurement at a rate of up to 0.1 degrees C/min, and this response could be evoked on demand. The results support the view that cooling of the upper airway can directly influence human brain temperature.
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Regulación de la Temperatura Corporal/fisiología , Encéfalo/fisiología , Fenómenos Fisiológicos Respiratorios , Adulto , Temperatura Corporal/fisiología , Femenino , Humanos , Aneurisma Intracraneal/cirugía , Intubación Intratraqueal , Masculino , Persona de Mediana Edad , Espacio Subdural/fisiologíaRESUMEN
OBJECTIVE: To examine the effect of consumption of medium-chain triglycerides (MCT) vs. long-chain triglycerides (LCT) on total energy expenditure (TEE) and its components in young women during the second week of a 2-week feeding period. RESEARCH METHODS AND PROCEDURES: Twelve healthy lean women (age: 22.7+/-0.7 years, body mass index [BMI]: 21.5+/-0.8 kg/m2) were fed weight maintenance diets containing 15% of energy as protein, 45% as carbohydrate, and 40% as fat, 80% of which was treatment fat, for 2 weeks in a randomized cross-over design separated by a 2-week washout period. Dietary fat was composed of triglycerides containing either 26% medium-chain fatty acids (MCFA) and 74% long-chain fatty acids (LCFA), or 2% MCFA and 98% LCFA. Free-living TEE was measured from day 7 to 14 on each dietary treatment using doubly labeled water (DLW). Basal metabolic rate (BMR) and thermic effect of food (TEF) were measured on days 7 and 14 using respiratory gas exchange analysis (RGE) for 30 minutes and 330 minutes, respectively. Activity-induced energy expenditure (AIEE) was derived as the difference between TEE and the sum of BMR and TEF. RESULTS: The average TEE while consuming the MCT diet (2246+/-98 kcal/day) did not differ from that of the LCT diet (2186+/-138 kcal/day. BMR was significantly higher on the MCT diet on day 7 (1219+/-38 kcal/day vs. 1179+/-42 kcal/day), but not on day 14; there was no effect of diet on TEF. There were no differences in BMR, TEF, or AIEE between diets when expressed as percentages of TEE. On average, BMR, TEF, and AIEE represented 54.6%, 8.2%, and 37.2%, respectively, of TEE. DISCUSSION: Results suggest that between day 7 and day 14 feeding of MCT vs. LCT at these levels, TEE is not affected and that increases seen in energy expenditure following MCT feeding may be of short duration. Thus, compensatory mechanisms may exist which blunt the effect of MCT on energy components over the longer term.
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Grasas de la Dieta/administración & dosificación , Metabolismo Energético/fisiología , Ácidos Grasos/química , Triglicéridos/metabolismo , Adulto , Estudios Cruzados , Deuterio/orina , Grasas de la Dieta/metabolismo , Ácidos Grasos/fisiología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Isótopos de Oxígeno/análisis , Intercambio Gaseoso Pulmonar/fisiología , Encuestas y Cuestionarios , Triglicéridos/administración & dosificación , Triglicéridos/químicaRESUMEN
Clinical laboratories and clinicians transmit certain laboratory test results to public health agencies as required by state or local law. Most of these surveillance data are currently received by conventional mail or facsimile transmission. The Centers for Disease Control and Prevention (CDC), Council of State and Territorial Epidemiologists, and Association of Public Health Laboratories are preparing to implement surveillance systems that will use existing laboratory information systems to transmit electronic laboratory results to appropriate public health agencies. The authors anticipate that this will improve the reporting efficiency for these laboratories, reduce manual data entry, and greatly increase the timeliness and utility of the data. The vocabulary and messaging standards used should encourage participation in these new electronic reporting systems by minimizing the cost and inconvenience to laboratories while providing for accurate and complete communication of needed data. This article describes public health data requirements and the influence of vocabulary and messaging standards on implementation.
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Sistemas de Información en Laboratorio Clínico , Redes de Comunicación de Computadores/normas , Vigilancia de la Población , Vocabulario Controlado , Centers for Disease Control and Prevention, U.S. , Técnicas de Laboratorio Clínico , Seguridad Computacional , Estudios de Evaluación como Asunto , Administración en Salud Pública , Estados UnidosRESUMEN
BACKGROUND: Medium-chain triacylglycerols (MCTs) are reported to enhance human energy expenditure (EE), although few studies have involved women and the duration of such effects is only known for periods of approximately 7 d. OBJECTIVE: This study was conducted to determine whether women consuming mixed, MCT-enriched or long-chain triacylglycerol (LCT)-enriched diets showed changes in EE or substrate oxidation after 7 and 14 d. DESIGN: Twelve nonobese, premenopausal women were fed isoenergetic mixed diets enriched in either MCTs or LCTs during separate, 14-d feeding periods. Each meal contained 40% of energy as fat (80% of which was the treatment fat), 45% as carbohydrate, and 15% as protein. On days 7 and 14 of each trial, basal metabolic rate (BMR, kJ/min), total energy expenditure (TEE, kJ/min), and thermic effect of feeding (deltakJ/min) after a standardized breakfast were measured by respiratory gas exchange. RESULTS: On day 7, the mean (+/-SEM) BMR (3.58+/-0.11 kJ/min) with the MCT diet was greater (P = 0.0003) than that with the LCT diet (3.43+/-0.11 kJ/min). The mean postprandial TEE on day 7 was significantly greater (P = 0.04) with the MCT diet (4.36+/-0.04 kJ/min) than with the LCT diet (4.23+/-0.04 kJ/min); by day 14, postprandial TEE was still greater with the MCT diet, but not significantly so. No significant differences in the thermic effect of feeding were evident between diets. CONCLUSIONS: Results from this longest controlled MCT feeding study to date suggest that short-term feeding of MCT-enriched diets increases TEE, but this effect could be transient with continued feeding.
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Grasas de la Dieta/administración & dosificación , Metabolismo Energético , Ácidos Grasos/administración & dosificación , Premenopausia/metabolismo , Adolescente , Adulto , Análisis de Varianza , Dióxido de Carbono/metabolismo , Femenino , Humanos , Consumo de Oxígeno , Periodo Posprandial , Factores de TiempoRESUMEN
BACKGROUND AND OBJECTIVE: Medical lasers have rapidly expanded in both indications and utilization. We have developed a simple model for the investigation of various modalities of lithotripsy using readily available silicate stones of uniform mass. MATERIALS AND METHODS: The holmium:YAG VersaPulse Select (Coherent, Palo Alto, CA) was used in these experiments to define the relation between fiber diameter and efficacy of stone fragmentation. For each fiber, lithotripsy was performed in an incremental fashion at 0.6, 0.8, and 1.0 J at a frequency of 10, 16, and 20 pulses per second at each energy level. RESULTS: Total kilojoules did not differ between any fibers investigated, supporting the consistency of our methodology. The power density of the holmium laser energy, as expressed as total kJ/area, decreases in proportion to increasing fiber diameter. We expected an increase in fragmentation success as fiber diameter decreased (at equal energy output). However, peak lithotripsy occurred with the 365- and 550-microm fibers, whereas neither the 200- nor the 1000-microm fibers was effective. CONCLUSION: This model utilizing a silicate stone phantom supports our clinical observation that the 365-microm fiber (and additionally the 550-microm fiber) provides the best method for efficient intracorporeal lithotripsy.