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1.
Nutr Neurosci ; 25(10): 2011-2022, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33926365

RESUMO

AIM: Individuals undernourished in utero or during early life are at high risk of developing obesity and metabolic disorders and show an increased preference for consuming sugary and fatty food. This study aimed at determining whether impaired taste detection and signalling in the lingual epithelium and the brain might contribute to this altered pattern of food intake. METHODS: The preference for feeding fat and sweet food and the expression in circumvallate papillae and hypothalamus of genes coding for sweet and fat receptors and transducing pathways were evaluated in adult rats born to control or calorie-restricted dams. Expression in the hypothalamus and the brain's reward system of genes involved in the homeostatic and hedonic control of food intake was also determined. RESULTS: Male and female undernourished animals exhibited increased expression in taste papillae and hypothalamus of T1R1, T1R2, CD36, gustducin, TRMP5 and PLC-ß2 genes, all of which modulate sweet and fat detection and intracellular signalling. However, the severity of the effect was greater in females than in males. Moreover, male, but not female, undernourished rats consumed more standard and sweetened food than their control counterparts and presented increased hypothalamic AgRP and NPY mRNAs levels together with enhanced dopamine transporter and dopamine receptor D2 expression in the ventral tegmental area. CONCLUSIONS: Maternal undernutrition induces sex-specific changes in food preferences and gene expression in taste papillae, hypothalamus and brain reward regions. The gene expression alterations in the male offspring are in line with their preference for consuming sugary and fatty food.


Assuntos
Desnutrição , Paladar , Proteína Relacionada com Agouti/metabolismo , Animais , Antígenos CD36/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Hipotálamo/metabolismo , Masculino , Desnutrição/metabolismo , Ratos , Receptores Dopaminérgicos/metabolismo
2.
Heredity (Edinb) ; 126(6): 896-912, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33846579

RESUMO

Inferring the demographic history of species is one of the greatest challenges in populations genetics. This history is often represented as a history of size changes, ignoring population structure. Alternatively, when structure is assumed, it is defined a priori as a population tree and not inferred. Here we propose a framework based on the IICR (Inverse Instantaneous Coalescence Rate). The IICR can be estimated for a single diploid individual using the PSMC method of Li and Durbin (2011). For an isolated panmictic population, the IICR matches the population size history, and this is how the PSMC outputs are generally interpreted. However, it is increasingly acknowledged that the IICR is a function of the demographic model and sampling scheme with limited connection to population size changes. Our method fits observed IICR curves of diploid individuals with IICR curves obtained under piecewise stationary symmetrical island models. In our models we assume a fixed number of time periods during which gene flow is constant, but gene flow is allowed to change between time periods. We infer the number of islands, their sizes, the periods at which connectivity changes and the corresponding rates of connectivity. Validation with simulated data showed that the method can accurately recover most of the scenario parameters. Our application to a set of five human PSMCs yielded demographic histories that are in agreement with previous studies using similar methods and with recent research suggesting ancient human structure. They are in contrast with the view of human evolution consisting of one ancestral population branching into three large continental and panmictic populations with varying degrees of connectivity and no population structure within each continent.


Assuntos
Fluxo Gênico , Genética Populacional , Diploide , Humanos , Densidade Demográfica
3.
Salud Publica Mex ; 63(5): 672-681, 2021 Sep 03.
Artigo em Espanhol | MEDLINE | ID: mdl-35099869

RESUMO

Objetivo. Analizar la gobernanza en el sistema de salud en México, en las políticas frente a la pandemia por Covid-19. Material y métodos. Estudio cualitativo, analítico, realizado entre junio y noviembre de 2020. Se analizaron 41 entrevistas semiestructuradas que se aplicaron a acto-res clave del sistema de salud y que se organizaron en el software ATLAS.ti 9. El análisis se adhirió a los principios teórico-metodológicos del Marco Analítico de Gobernanza. Resultados. El problema: la formulación de políticas fue centralizada; los actores: sólo los altos mandos participan en las decisiones; las normas: los valores sociales y el liderazgo determinan su nivel de responsabilidad; toma de decisio-nes: los altos mandos reconocieron poder para proponer modificaciones al Marco Normativo; los nodos: las políticas federales fueron adaptadas a nivel estatal de manera diferen-ciada. Conclusiones. La gobernanza centralizada, los niveles diferenciados de convocatoria de los actores, su poder de decisión, acuerdos, responsabilidad y liderazgo, definieron el alcance de la gobernanza y, a su vez, el nivel de respuesta ante la pandemia por Covid-19.


Assuntos
COVID-19 , Programas Governamentais , Humanos , México/epidemiologia , Pandemias , SARS-CoV-2
4.
Int J Health Plann Manage ; 36(2): 579-586, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33368667

RESUMO

Taking the Mexican case as a tracer of what is happening in Latin America on public health, we estimate the recent changes and challenges for the management of hypertension in older adults in the context of universal health coverage. The population base was 200, and 308 reported cases of older adults with hypertension. The cost-evaluation method used was based on the instrumentation and consensus technique. Regarding epidemiological changes for 2016 versus 2018, there is an increase of 21% (CI: 95%, p < 0.001). Comparing the economic impact in 2016 versus 2018 (CI: 95%, p < 0.001), the increase is 33%. The total amount estimated for hypertension in 2018 (in US dollars) was $ 1,896,520,273. It includes $ 898,064,979 as direct costs and $ 998,455,294 as indirect costs. The recent trends show that the financial requirements for the coming years do not guarantee the effectiveness of the coverage rates required for the elderly. In terms of catastrophic expenditure, the challenge is not minor, the greatest economic burden is for the pocket of patients and their families.


Assuntos
Hipertensão , Cobertura Universal do Seguro de Saúde , Idoso , Custos de Cuidados de Saúde , Humanos , Hipertensão/epidemiologia , Hipertensão/terapia , América Latina/epidemiologia , México
5.
Heredity (Edinb) ; 121(6): 663-678, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30293985

RESUMO

In the last years, a wide range of methods allowing to reconstruct past population size changes from genome-wide data have been developed. At the same time, there has been an increasing recognition that population structure can generate genetic data similar to those produced under models of population size change. Recently, Mazet et al. (Heredity 116:362-371, 2016) showed that, for any model of population structure, it is always possible to find a panmictic model with a particular function of population size changes, having exactly the same distribution of T2 (the coalescence time for a sample of size two) as that of the structured model. They called this function IICR (Inverse Instantaneous Coalescence Rate) and showed that it does not necessarily correspond to population size changes under non-panmictic models. Besides, most of the methods used to analyse data under models of population structure tend to arbitrarily fix that structure and to minimise or neglect population size changes. Here, we extend the seminal work of Herbots (PhD thesis, University of London, 1994) on the structured coalescent and propose a new framework, the Non-Stationary Structured Coalescent (NSSC) that incorporates demographic events (changes in gene flow and/or deme sizes) to models of nearly any complexity. We show how to compute the IICR under a wide family of stationary and non-stationary models. As an example we address the question of human and Neanderthal evolution and discuss how the NSSC framework allows to interpret genomic data under this new perspective.


Assuntos
Demografia , Densidade Demográfica , Humanos , Modelos Teóricos
6.
Global Health ; 14(1): 89, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30143010

RESUMO

BACKGROUND: Despite more than 20 years of reform projects in health systems, the universal coverage strategy has not reached the expected results in most middle-income countries (MICs). Using evidence from the Mexican case on diabetes and hypertension as tracers of non-communicable diseases, the effective coverage rate barely surpasses half of the expected goals necessary to meet the challenges that these two diseases represent at the population level. Prevalence and incidence rates do not diminish either; they even grow. In terms of the economic burden, this means that lack of financial protection and catastrophic expense rates have increased, contrary to what could have been expected. DISCUSSION: As any complex system, health systems present challenges and dilemmas that are difficult to solve. In terms of universal coverage, when contrasting normative coverage versus effective coverage, the epidemiological, cultural, organizational and economic challenges and barriers become evident. Such challenges have not allowed a greater effectiveness of the contributions of state of the art medicine in the resolution of health problems, particularly in relation to diabetes and hypertension. CONCLUSIONS: Despite of the existence of many universal coverage projects, strategies and programs implemented in MICs, challenges remain and, far from disappearing, unresolved problems are still present, even with increasing trends. The model of care based on a curative biomedical approach was enough to respond to the health needs of the last century, but is no longer adapted to the needs of the present century. The dilemmas of continuity vs. rupture require to review and discuss the background and structure of health systems and their underlying models of care. These two elements have not allowed the different coverage schemes to guarantee greater effectiveness in the application of state of the art medicine, nor a greater health care financial protection for patients and their families. We thus can either accept the fragmented health systems and bio-medical-curative models of care approach or, instead, we can move towards integrated health systems that would be based on a socio-medical-preventive approach to health care.


Assuntos
Países em Desenvolvimento , Doenças não Transmissíveis/prevenção & controle , Cobertura Universal do Seguro de Saúde , Diabetes Mellitus/economia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/prevenção & controle , Humanos , Hipertensão/economia , Hipertensão/epidemiologia , Hipertensão/prevenção & controle , México/epidemiologia , Doenças não Transmissíveis/economia , Doenças não Transmissíveis/epidemiologia , Avaliação de Programas e Projetos de Saúde
8.
Int J Health Plann Manage ; 32(2): e121-e136, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27238949

RESUMO

This study estimated the epidemiological and financial indicators of hypertension in order to identify challenges in strategic planning and management for health systems in Latin America. This is a longitudinal study with a population base of 187 326 reported cases of older adults with hypertension, diagnosed at public health institutions in Mexico. The cost-evaluation method that was used was based on the instrumentation and consensus techniques. To estimate the epidemiological changes and financial consequences for 2015-2017, time series analyses and probabilistic models were constructed according to the Box-Jenkins technique. Regarding epidemiological changes for 2015 versus 2017, an increase of 8-12% is expected (p < 0.001). Comparing the economic impact in 2015 versus 2017 (p < 0.001), there is a 22% increase in financial requirements. The total amount estimated for hypertension in 2015 (in US dollars) was $1 575 671 330. It included $747 527 259 as direct costs and $829 144 071 as indirect costs. If the risk factors and the different healthcare services for older adults remain as they are currently, the financial consequences of epidemiological changes in older adults will have a major impact on the users' pockets, following in order of importance, on social security providers and on public assistance providers. The challenges and implications of our findings in the context of universal coverage reforms in Latin America reinforce the urgent need to develop more and better strategic planning for the prevention of chronic diseases. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Planejamento em Saúde , Hipertensão/economia , Hipertensão/epidemiologia , Idoso , Custos e Análise de Custo , Humanos , América Latina , Estudos Longitudinais , México/epidemiologia , Saúde Pública
10.
Rev Panam Salud Publica ; 39(6): 330-340, 2016 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-27706437

RESUMO

Objective The objective of this study was to identify the availability of health indicators for validly measuring advances in the attainment of "universal health" in Latin America and the Caribbean (LAC). Methods A systematic search was undertaken for scientific evidence and available technical and scientific documents on assessing health system performance and advances in universal health in the following phases: phase 1, mapping of indicators; phase 2, classification of indicators; and phase 3, mapping the availability of selected indicators in LAC. Results Sixty-three (63) national sources of information and eight international sources were identified. A total of 749 indicators were selected from the different databases and studies evaluated, 619 of which were related to the attainment of universal health and 130 to the burden of disease. The following indicators were identified: financial protection, 42 (6%); coverage of service delivery, 415 (55.4%); population coverage, 6 (0.8%); health determinants, 101 (14%); assessment of inequalities in health, 55 (7.3%); and estimation of burden of disease, 130 (17.3%). Finally, the availability of 141 indicators was mapped for each LAC country. Conclusions The results of this study will help establish a framework for measuring the achievements, obstacles, and rate of progress toward universal health in LAC.


Assuntos
Logro , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Indicadores Básicos de Saúde , Disparidades em Assistência à Saúde/estatística & dados numéricos , Região do Caribe , Acessibilidade aos Serviços de Saúde/economia , Humanos , América Latina , Fatores Socioeconômicos
11.
BMC Public Health ; 15: 1106, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26546356

RESUMO

BACKGROUND: In order to identify the challenges resulting from hypertension in a middle income country, this study has developed probabilistic models to determine the epidemiological and economic burden of hypertension in Mexico. METHODS: Considering a population base of 654,701 reported cases of adults with hypertension, we conducted a longitudinal analyses in order to identify the challenges of epidemiological changes and health care costs for hypertension in the Mexican health system. The cost-evaluation method used was based on the instrumentation technique. To estimate the epidemiological changes for 2015-2017, probabilistic models were constructed according to the Box-Jenkins technique. RESULTS: Regarding changes in expected cases for 2015 vs. 2017, an increase of 12 % is expected (p < 0.001). Comparing the economic impact in 2015 versus 2017 (p < 0.001), there is a 23 % increase in financial requirements. The total amount for hypertension in 2016 (US dollars) will be $6306,685,320 Of these, $ 2990,109,035 will be as direct costs and $ 3316,576,285 as indirect costs. CONCLUSIONS: If the risk factors and care models remain as they are currently in the health system, the financial consequences will have a major impact on the out-of-pocket users, following in order of importance, on social security providers and on public assistance providers.


Assuntos
Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde , Hipertensão/economia , Hipertensão/epidemiologia , Adulto , Feminino , Humanos , Renda , Estudos Longitudinais , Masculino , México/epidemiologia , Fatores de Risco
13.
BMC Med ; 12: 136, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25266304

RESUMO

BACKGROUND: Despite advances in medicine, health systems in Latin America are not coping with the challenges of chronic diseases. Incidence of disease and the economic burdens as a consequence have both increased in recent years. We have chosen Type 2 diabetes as an example to highlight the challenges posed by chronic diseases, in terms of the epidemiological transition and the economic burden of the demand for services to treat such problems. DISCUSSION: Current health systems are not prepared to respond in a comprehensive manner to all phases of the natural history of the disease. There are new models of universal coverage, but resources and models of care are focused on programs aimed at healing/rehabilitation, and very sparsely at detection/prevention. SUMMARY: In this scenario, chronic problems have alarmingly increased direct costs (medical care) and indirect costs (temporary disability, permanent disability and premature mortality). If more resources are not assigned to preventive medicine, these trends, in addition to not meeting the needs of the population, will financially collapse health systems and the patients' pockets. This Opinion piece outlines some possible changes that can be implemented to better prepare the health services in Latin American countries.


Assuntos
Diabetes Mellitus Tipo 2/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Serviços de Saúde , Humanos , América Latina/epidemiologia
14.
Int J Health Plann Manage ; 34(1): e713-e725, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30350426

RESUMO

Maternal obesity is one of the main public health problems at a world level. It is a multifactorial disease with multiple causes, and few studies exist on its dietary patterns, physical activity and social determinants. This work aims to identify determinants of maternal obesity in a middle income country. Research is based on a prospective cohort design. Data were collected using questionnaires applied to pregnant women. Three dietary patterns were identified, and only half of the women carry out physical activity. The regression analysis showed an association between overweight/obesity and the following variables: age 25 to 29 years old (3.8; CI 1.6-9.0), 30 to 34 years old (3.7; CI 1.2-11.6); health problems during pregnancy (2.1; CI 1.0-4.1); socio-economic income (1.73; CI 1.54-2.05); hypertension (2.7; CI 1.4-4.5); mild food insecurity (1.9; CI 1.0-3.8); moderate insecurity (3.7; CI 0.92-15.4); refined food dietary pattern (.76; CI.61-.95). The risk of increasing BMI during pregnancy mainly depends on socioeconomic and demographic variables such as age, educational level, income, food insecurity, and dietary pattern. This study's results could be used as evidences for the revision, planning, and adjustment of interventions for the prevention and management of maternal obesity, as a part of the national strategies against overweight and obesity.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Dieta/efeitos adversos , Exercício Físico , Obesidade Materna/etiologia , Adolescente , Adulto , Dieta/estatística & dados numéricos , Feminino , Humanos , México/epidemiologia , Obesidade Materna/epidemiologia , Gravidez , Estudos Prospectivos , Fatores de Risco , Determinantes Sociais da Saúde , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
15.
Global Health ; 9: 3, 2013 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-23374611

RESUMO

BACKGROUND: Mexico has been experiencing some of the most rapid shifts ever recorded in dietary and physical activity patterns leading to obesity. Diabetes mellitus has played a crucial role causing nearly 14% of all deaths. We wanted to make a comprehensive study of the role of diabetes in terms of burden of disease, prevalence, cost of diabetes, cost of complications and health policy. METHOD: We review the quantitative data that provides evidence of the extent to which the Mexican health economy is affected by the disease and its complications. We then discuss the current situation of diabetes in Mexico with experts in the field. RESULTS: There was a significant increase in the prevalence of diabetes from 1994 to 2006 with rising direct costs (2006: outpatient USD$ 717,764,787, inpatient USD$ 223,581,099) and indirect costs (2005: USD$ 177,220,390), and rising costs of complications (2010: Retinopathy USD$ 10,323,421; Cardiovascular disease USD$ 12,843,134; Nephropathy USD$ 81,814,501; Neuropathy USD$ 2,760,271; Peripheral vascular disease USD$ 2,042,601). The health policy focused on screening and the creation of self-support groups across the country. CONCLUSIONS: The increasing diabetes mortality and lack of control among diagnosed patients make quality of treatment a major concern in Mexico. The growing prevalence of childhood and adult obesity and the metabolic syndrome suggest that the situation could be even worse in the coming years. The government has reacted strongly with national actions to address the growing burden posed by diabetes. However our research suggests that the prevalence and mortality of diabetes will continue to rise in the future.


Assuntos
Efeitos Psicossociais da Doença , Complicações do Diabetes/economia , Diabetes Mellitus/economia , Adulto , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/terapia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Feminino , Política de Saúde , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade
16.
Salud Publica Mex ; 55 Suppl 4: S508-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25153191

RESUMO

OBJECTIVE: To identify policies that increase access to health care for undocumented Mexican immigrants. MATERIALS AND METHODS: Four focus groups (n=34 participants) were conducted with uninsured Mexican immigrants in Los Angeles, California. The feasibility and desirability of different policy proposals for increasing access were discussed by each group. RESULTS: Respondents raised significant problems with policies including binational health insurance, expanded employer-provided health insurance, and telemedicine. The only solution with a consensus that the change would be feasible, result in improved access, and they had confidence in was expanded access to community health centers (CHC's). CONCLUSIONS: Given the limited access to most specialists at CHC's and the continued barriers to hospital care for those without health insurance, the most effective way of improving the complete range of health services to undocumented immigrants is through immigration reform that will bring these workers under the other health care reform provisions.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Imigrantes Indocumentados , California , Humanos , Seguro Saúde , México/etnologia
18.
Salud Publica Mex ; 54(1): 20-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22286825

RESUMO

OBJECTIVE: To assess the impact of a workplace leisure physical activity program on healthcare expenditures for type 2 diabetes and hypertension treatment. MATERIAL AND METHODS: We assessed a workplace program's potential to reduce costs by multiplying the annual healthcare costs of patients with type 2 diabetes and hypertension by the population attributable risk fraction of non-recommended physical activity levels. Feasibility of a physical activity program was assessed among 425 employees of a public university in Mexico. RESULTS: If 400 sedentary employees engaged in a physical activity program to decrease their risk of diabetes and hypertension, the potential annual healthcare cost reduction would be 138 880 US dollars. Each dollar invested in physical activity could reduce treatment costs of both diseases by 5.3 dollars. CONCLUSIONS: This research meets the call to use health economics methods to re-appraise health priorities, and devise strategies for optimal allocation of financial resources in the health sector.


Assuntos
Diabetes Mellitus Tipo 2/economia , Diabetes Mellitus Tipo 2/terapia , Custos de Cuidados de Saúde , Hipertensão/economia , Hipertensão/terapia , Atividade Motora , Saúde Ocupacional/economia , Local de Trabalho , Adulto , Estudos Transversais , Feminino , Humanos , Masculino
19.
Int J Health Plann Manage ; 27(1): 50-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21823167

RESUMO

OBJECTIVE: This article aims to identify opportunities, barriers and challenges in Mexico's policy networks for the development of healthcare programs for undocumented migrants in the USA and their families. METHODS: We used policy analysis, in-depth interviews and a case study. Key stakeholders at the federal, state and municipal levels in one major migrant-sending state were interviewed. We also conducted an in-depth case study of one community to obtain the perceptions of local health workers, migrant families and local nongovernmental organizations. RESULTS: Findings identified opportunities and barriers involving the stakeholders, institutions, social interactions and types of relationships necessary for further progress on binational policies. There was wide interest in creating binational health insurance with different degrees of potential involvement by political actors and variation in local actors' willingness to be covered by some type of health insurance scheme. CONCLUSIONS: The use of the opportunities to overcome barriers depends on the identification of high, medium or low interaction among key stakeholders, integration of coalitions and negotiating skills of all stakeholders involved.


Assuntos
Emigrantes e Imigrantes/legislação & jurisprudência , Cobertura do Seguro , Seguro Saúde , Humanos , Entrevistas como Assunto , México , Estados Unidos
20.
Genetics ; 220(3)2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35100421

RESUMO

The relative contribution of selection and neutrality in shaping species genetic diversity is one of the most central and controversial questions in evolutionary theory. Genomic data provide growing evidence that linked selection, i.e. the modification of genetic diversity at neutral sites through linkage with selected sites, might be pervasive over the genome. Several studies proposed that linked selection could be modeled as first approximation by a local reduction (e.g. purifying selection, selective sweeps) or increase (e.g. balancing selection) of effective population size (Ne). At the genome-wide scale, this leads to variations of Ne from one region to another, reflecting the heterogeneity of selective constraints and recombination rates between regions. We investigate here the consequences of such genomic variations of Ne on the genome-wide distribution of coalescence times. The underlying motivation concerns the impact of linked selection on demographic inference, because the distribution of coalescence times is at the heart of several important demographic inference approaches. Using the concept of inverse instantaneous coalescence rate, we demonstrate that in a panmictic population, linked selection always results in a spurious apparent decrease of Ne along time. Balancing selection has a particularly large effect, even when it concerns a very small part of the genome. We also study more general models including genuine population size changes, population structure or transient selection and find that the effect of linked selection can be significantly reduced by that of population structure. The models and conclusions presented here are also relevant to the study of other biological processes generating apparent variations of Ne along the genome.


Assuntos
Genoma , Genômica , Modelos Genéticos , Densidade Demográfica , Seleção Genética
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