Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Nature ; 555(7694): 48-53, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29493588

RESUMEN

Educational attainment for women of reproductive age is linked to reduced child and maternal mortality, lower fertility and improved reproductive health. Comparable analyses of attainment exist only at the national level, potentially obscuring patterns in subnational inequality. Evidence suggests that wide disparities between urban and rural populations exist, raising questions about where the majority of progress towards the education targets of the Sustainable Development Goals is occurring in African countries. Here we explore within-country inequalities by predicting years of schooling across five by five kilometre grids, generating estimates of average educational attainment by age and sex at subnational levels. Despite marked progress in attainment from 2000 to 2015 across Africa, substantial differences persist between locations and sexes. These differences have widened in many countries, particularly across the Sahel. These high-resolution, comparable estimates improve the ability of decision-makers to plan the precisely targeted interventions that will be necessary to deliver progress during the era of the Sustainable Development Goals.


Asunto(s)
Escolaridad , Adolescente , Adulto , África , Femenino , Objetivos , Humanos , Internacionalidad , Masculino , Persona de Mediana Edad , Probabilidad , Factores Sexuales , Organización Mundial de la Salud , Adulto Joven
2.
Nature ; 555(7694): 41-47, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29493591

RESUMEN

Insufficient growth during childhood is associated with poor health outcomes and an increased risk of death. Between 2000 and 2015, nearly all African countries demonstrated improvements for children under 5 years old for stunting, wasting, and underweight, the core components of child growth failure. Here we show that striking subnational heterogeneity in levels and trends of child growth remains. If current rates of progress are sustained, many areas of Africa will meet the World Health Organization Global Targets 2025 to improve maternal, infant and young child nutrition, but high levels of growth failure will persist across the Sahel. At these rates, much, if not all of the continent will fail to meet the Sustainable Development Goal target-to end malnutrition by 2030. Geospatial estimates of child growth failure provide a baseline for measuring progress as well as a precision public health platform to target interventions to those populations with the greatest need, in order to reduce health disparities and accelerate progress.


Asunto(s)
Desarrollo Infantil , Trastornos del Crecimiento/epidemiología , Crecimiento , Desnutrición/epidemiología , Síndrome Debilitante/epidemiología , África/epidemiología , Preescolar , Femenino , Objetivos , Trastornos del Crecimiento/prevención & control , Humanos , Lactante , Recién Nacido , Masculino , Desnutrición/prevención & control , Prevalencia , Salud Pública/estadística & datos numéricos , Delgadez/epidemiología , Delgadez/prevención & control , Síndrome Debilitante/prevención & control , Organización Mundial de la Salud
3.
Alcohol Clin Exp Res ; 46(11): 1967-1979, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36117381

RESUMEN

BACKGROUND: Recent work suggests that a history of chronic alcohol exposure can enhance the influence of nondrug reward cues on ongoing actions. This is often modeled in Pavlovian-to-instrumental transfer (PIT) tasks that examine the interaction between Pavlovian and instrumental learning processes, usually reflected as an increase in action vigor during the presentation of a reward-associated cue. Though prior chronic alcohol exposure strengthens this type of cue-guided behavior, the neural mechanisms underlying such enhancements are not known. METHODS: In the present work, we examined the contribution of the central amygdala (CeA), a region strongly implicated in PIT behaviors and functionally altered by chronic alcohol exposure. We utilized Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to examine the impact of inhibitory and excitatory CeA manipulation on PIT behaviors in alcohol-naïve mice and mice with a history of chronic intermittent ethano vapor exposure and withdrawal (CIE). RESULTS: Replicating previous work, we found that a history of CIE strengthened baseline PIT, in the absence of any CeA manipulation. We also found that activation of both inhibitory and excitatory DREADDs expressed in CeA enhanced PIT in alcohol-naïve mice, though the latter markedly reduced response rates. However, in mice exposed to CIE, activation of excitatory DREADD receptors expressed in CeA appeared to weaken PIT. CONCLUSIONS: These results suggest that alcohol-induced disruptions in amygdala function may contribute to changes in appetitive behaviors, such as cue-guided responding, following chronic exposure to alcohol. Better elucidating the neural mechanisms that underlie disrupted cue-guided behavior following chronic alcohol exposure may help to understand and treat deficits in adaptive behavior associated with chronic alcohol use in humans.


Asunto(s)
Núcleo Amigdalino Central , Humanos , Ratones , Animales , Condicionamiento Operante , Etanol/farmacología , Recompensa , Señales (Psicología)
4.
Alcohol Clin Exp Res ; 44(10): 1952-1964, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32852095

RESUMEN

Alcoholism is a persistent worldwide problem associated with long-lasting impairments to decision making processes. Some aspects of dysfunction are thought to reflect alcohol-induced changes to relevant brain areas such as the orbitofrontal cortex (OFC). In this review, we will examine how chronic alcohol exposure alters OFC function to potentially contribute to maladaptive decision making, and explore experimental behavioral approaches that may be better suited to test whether alcohol dependence disrupts OFC's function. We argue that although past works suggest impairments in aspects of OFC function, more information may be gained by specifically targeting tasks to the broader function of OFC as put forth by the recent hypothesis of OFC as a "cognitive map" of task space. Overall, we suggest that such a focus could provide a better understanding of how OFC function changes in alcohol dependence, and could inform better assessment tools and treatment options for clinicians working with this population.


Asunto(s)
Alcoholismo/fisiopatología , Mapeo Encefálico , Toma de Decisiones/fisiología , Corteza Prefrontal/fisiopatología , Alcoholismo/etiología , Animales , Cognición/fisiología , Humanos
5.
Alcohol ; 101: 53-64, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35405249

RESUMEN

Dysfunctional decision-making has been observed in alcohol dependence. However, the specific underlying processes disrupted have yet to be identified. Important to goal-directed decision-making is one's motivational state, which is used to update the value of actions. As ethanol dependence disrupts decision-making processes, we hypothesized that ethanol dependence could alter sensitivity to motivational state and/or value updating, thereby reducing the capability for adaptive behavior. Here we employed a sequential instrumental learning task to examine this hypothesis. In two experiments, mice underwent chronic intermittent ethanol (CIE) or air (Air) vapor exposure and repeated withdrawal procedures to induce ethanol dependence. Mice were then trained on a sequence of distal and proximal lever pressing for sucrose under either mild or more severe food restriction. Half of all Air and CIE mice then underwent a motivational shift to a less hungry state and effects of this motivational shift were evaluated across three days. First, mice were re-exposed to sucrose, and effects of food restriction state and CIE exposure on lick and consummatory behavior were examined in the absence of lever pressing. Over the next two days, mice underwent a brief non-rewarded test and then a rewarded test where the ability to retrieve and infer sucrose value to guide lever pressing was measured. In the sucrose re-exposure session, prior CIE exposure altered sucrose-seeking in mice with a history of mild but not more severe food restriction, suggesting altered motivational sensitivity. During lever press testing, CIE mice were insensitive to decreases in motivational state and did not reduce proximal lever pressing regardless of food restriction state. Mildly restricted CIE mice, but not severely restricted CIE mice, also did not reduce distal pressing to the same degree as Air mice following a downshift in motivational state. Our findings suggest that ethanol dependence may disrupt motivational processes supporting value updating that are important for decision-making.


Asunto(s)
Alcoholismo , Motivación , Animales , Condicionamiento Operante , Etanol/farmacología , Ratones , Ratones Endogámicos C57BL , Sacarosa
6.
Alcohol ; 96: 83-92, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34363928

RESUMEN

Alcohol dependence is associated with aberrant decision-making processes, particularly in the presence of alcohol-related environmental cues. For instance, alcohol cues can trigger alcohol seeking, consumption, and even relapse behavior. Recently, works have suggested that alcohol dependence may induce more general alterations in cued processes that support adaptive behavior, including enhanced cue control of volitional behavior unrelated to alcohol use. Here we examine this hypothesis by combining prior exposure to chronic intermittent ethanol and repeated withdrawal (CIE) procedures with a Pavlovian-to-instrumental transfer (PIT) task in mice. The PIT task entails training a Pavlovian association, separately training an instrumental contingency, and a final test during which the Pavlovian cue and instrumental action are combined for the first time. We first tested two variants of the PIT procedure in ethanol-naïve mice, differing in part in the duration of Pavlovian conditioned cues (short or long). We found in the PIT test that the short cue procedure produced negative transfer, whereas the long cue procedure produced positive transfer. We then used the long cue variant to examine PIT behavior in mice previously exposed to either CIE or air vapor. We found that prior CIE exposure strengthened PIT behavior, with enhanced instrumental responding during presentation of the food-associated cue. We further found that this enhancement in CIE mice persisted even after devaluation of the food outcome. Our findings suggest that ethanol dependence can enhance the influence of reward-predictive cues on ongoing behavior. Greater non-alcohol cue control of behavior may reflect the effect of chronic ethanol exposure on neural circuitry critical for cue-guided behavior in general.


Asunto(s)
Condicionamiento Clásico , Condicionamiento Operante , Animales , Señales (Psicología) , Etanol , Ratones , Transferencia de Experiencia en Psicología
8.
Nat Med ; 25(8): 1205-1212, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31332393

RESUMEN

Exclusive breastfeeding (EBF)-giving infants only breast-milk (and medications, oral rehydration salts and vitamins as needed) with no additional food or drink for their first six months of life-is one of the most effective strategies for preventing child mortality1-4. Despite these advantages, only 37% of infants under 6 months of age in Africa were exclusively breastfed in 20175, and the practice of EBF varies by population. Here, we present a fine-scale geospatial analysis of EBF prevalence and trends in 49 African countries from 2000-2017, providing policy-relevant administrative- and national-level estimates. Previous national-level analyses found that most countries will not meet the World Health Organization's Global Nutrition Target of 50% EBF prevalence by 20256. Our analyses show that even fewer will achieve this ambition in all subnational areas. Our estimates provide the ability to visualize subnational EBF variability and identify populations in need of additional breastfeeding support.


Asunto(s)
Lactancia Materna/estadística & datos numéricos , África/epidemiología , Femenino , Infecciones por VIH/transmisión , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Prevalencia , Factores de Tiempo , Organización Mundial de la Salud
9.
JAMA Pediatr ; 173(6): e190337, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31034019

RESUMEN

Importance: Understanding causes and correlates of health loss among children and adolescents can identify areas of success, stagnation, and emerging threats and thereby facilitate effective improvement strategies. Objective: To estimate mortality and morbidity in children and adolescents from 1990 to 2017 by age and sex in 195 countries and territories. Design, Setting, and Participants: This study examined levels, trends, and spatiotemporal patterns of cause-specific mortality and nonfatal health outcomes using standardized approaches to data processing and statistical analysis. It also describes epidemiologic transitions by evaluating historical associations between disease indicators and the Socio-Demographic Index (SDI), a composite indicator of income, educational attainment, and fertility. Data collected from 1990 to 2017 on children and adolescents from birth through 19 years of age in 195 countries and territories were assessed. Data analysis occurred from January 2018 to August 2018. Exposures: Being under the age of 20 years between 1990 and 2017. Main Outcomes and Measures: Death and disability. All-cause and cause-specific deaths, disability-adjusted life years, years of life lost, and years of life lived with disability. Results: Child and adolescent deaths decreased 51.7% from 13.77 million (95% uncertainty interval [UI], 13.60-13.93 million) in 1990 to 6.64 million (95% UI, 6.44-6.87 million) in 2017, but in 2017, aggregate disability increased 4.7% to a total of 145 million (95% UI, 107-190 million) years lived with disability globally. Progress was uneven, and inequity increased, with low-SDI and low-middle-SDI locations experiencing 82.2% (95% UI, 81.6%-82.9%) of deaths, up from 70.9% (95% UI, 70.4%-71.4%) in 1990. The leading disaggregated causes of disability-adjusted life years in 2017 in the low-SDI quintile were neonatal disorders, lower respiratory infections, diarrhea, malaria, and congenital birth defects, whereas neonatal disorders, congenital birth defects, headache, dermatitis, and anxiety were highest-ranked in the high-SDI quintile. Conclusions and Relevance: Mortality reductions over this 27-year period mean that children are more likely than ever to reach their 20th birthdays. The concomitant expansion of nonfatal health loss and epidemiological transition in children and adolescents, especially in low-SDI and middle-SDI countries, has the potential to increase already overburdened health systems, will affect the human capital potential of societies, and may influence the trajectory of socioeconomic development. Continued monitoring of child and adolescent health loss is crucial to sustain the progress of the past 27 years.


Asunto(s)
Salud del Adolescente/tendencias , Salud Infantil/tendencias , Carga Global de Enfermedades/tendencias , Salud Global/tendencias , Morbilidad/tendencias , Heridas y Lesiones/epidemiología , Adolescente , Distribución por Edad , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Años de Vida Ajustados por Calidad de Vida , Factores de Riesgo , Distribución por Sexo , Factores Socioeconómicos , Análisis Espacio-Temporal , Heridas y Lesiones/etiología , Adulto Joven
10.
Psychopharmacology (Berl) ; 235(12): 3535-3543, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30343365

RESUMEN

RATIONALE: Previous work has shown that some mouse strains (e.g., DBA/2J [D2]) readily develop robust ethanol-induced conditioned place preference (CPP) while others (e.g., C57BL/6J [B6]) do not. Though commonly interpreted as a difference between strains in sensitivity to ethanol reward, other explanations for this finding are possible. OBJECTIVES: To explore the hypothesis that variation in sensitivity to contextual cues underlies CPP differences, the present work investigated ethanol-induced CPP in D2 and B6 mice trained with a standard tactile (floor) cue procedure compared to mice trained with tactile plus visual-spatial cues. METHODS: In an unbiased CPP procedure, mice were assigned to either a single element cue (one-compartment apparatus with tactile cue presented in the dark) or multi-modal cues (two-compartment apparatus with distinct tactile floors and lights on). To track CPP development, mice received preference tests during training in addition to a final test. RESULTS: Adding visual-spatial cues accelerated CPP acquisition in both D2 and B6 mice. However, this enhancement was observed after just one ethanol-conditioning trial in D2 mice, but was observed only after four ethanol-conditioning trials in B6 mice. Differences between groups trained with single or multi-modal cues disappeared as conditioning reached asymptote, with D2 mice showing a more rapid loss of the effect and a higher maximum CPP. CONCLUSIONS: Although multi-modal cues produce more rapid conditioning, their inability to reduce or eliminate strain differences in CPP supports the interpretation that these strains differ in their sensitivity to ethanol reward.


Asunto(s)
Condicionamiento Clásico/efectos de los fármacos , Condicionamiento Clásico/fisiología , Señales (Psicología) , Etanol/administración & dosificación , Locomoción/efectos de los fármacos , Locomoción/fisiología , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Estimulación Luminosa/métodos , Recompensa , Conducta Espacial/efectos de los fármacos , Conducta Espacial/fisiología , Especificidad de la Especie
11.
Pharmacol Biochem Behav ; 173: 84-89, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30036544

RESUMEN

Previous studies of ethanol drinking in rodents have shown greater intake in females than in males, but the reasons behind this difference are unknown. To address one possible interpretation of the drinking difference, these studies tested the hypothesis that female and male mice differ in sensitivity to the rewarding effects of ethanol using the conditioned place preference (CPP) procedure. To increase the generalizability of the results, sex differences were examined in two inbred mouse strains known to differ in their sensitivity to ethanol reward: C57BL/6J (B6) and DBA/2J (D2). Mice were conditioned in an unbiased CPP procedure using either 1 or 2 g/kg ethanol. To detect possible differences in learning rate, they were tested once at the midpoint of conditioning and again after conditioning ended. As expected, CPP was stronger with 2 g/kg than with 1 g/kg, and D2 mice generally showed stronger CPP than B6 mice. However, there were no sex differences in the rate of CPP acquisition or in CPP magnitude, suggesting no sex difference in ethanol reward sensitivity as indexed by CPP. Nevertheless, there were sex differences in locomotor activity. B6 females were generally more active than B6 males during CPP acquisition whereas D2 females were slightly less active than D2 males during both CPP acquisition and preference testing. Unexpectedly, female mice showed more variability than males in the behavioral measures recorded in these studies, encouraging greater attention to variability in the design, analysis and interpretation of future studies of sex differences in mice.


Asunto(s)
Condicionamiento Clásico/efectos de los fármacos , Etanol/farmacología , Factores Sexuales , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA