Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Rev Panam Salud Publica ; 46, 2022. Special Issue HEARTS
Artículo en Inglés | PAHO-IRIS | ID: phr-56395

RESUMEN

[ABSTRACT]. Hypertension remains the leading cause of cardiovascular disease globally despite the availability of safe and effective treatments. Unfortunately, many barriers exist to controlling hypertension, including a lack of effective screening and awareness, an inability to access treatment and challenges with its management when it is treated. Addressing these barriers is complex and requires engaging in a systematic and sustained approach across communities over time. This analysis aims to describe the key elements needed to create an effective delivery system for hypertension control. A successful system requires political will and supportive leadership at all levels of an organization, including at the point of care delivery (office or clinic), in the health care system, and at regional, state and national levels. Effective screening and outreach systems are necessary to identify individuals not previously diagnosed with hypertension, and a system for follow up and tracking is needed after people are diagnosed. Implementing simple protocols for treating hypertension can reduce confusion among providers and increase treatment efficiency. Ensuring easy access to safe, effective and affordable medica- tions can increase blood pressure control and potentially decrease health care system costs. Task-sharing among members of the health care team can expand the services that are delivered. Finally, monitoring of and reporting on the performance of the health care team are needed to learn from those who are doing well, disseminate ideas to those in need of improvement and identify individual patients who need outreach or additional care. Successful large-scale hypertension programs in different settings share many of these key elements and serve as examples to improve systems of hypertension care delivery throughout the world.


[RESUMEN]. A pesar de la disponibilidad de tratamientos seguros y efectivos, la hipertensión sigue siendo la principal causa de enfermedad cardiovascular a nivel mundial. Lamentablemente, el control de la hipertensión enfrenta muchos obstáculos, como la falta de detección y concientización efectivas, la incapacidad de acceder al tratamiento y los retos que plantea su manejo cuando se recibe tratamiento. Resulta complejo abordar estos obstáculos; se debe adoptar un enfoque sistemático y sostenido en todas las comunidades a lo largo del tiempo. El presente análisis tiene como objetivo describir los elementos clave necesarios para crear un sistema de atención eficaz para el control de la hipertensión. Un sistema adecuado precisa voluntad política y un liderazgo que brinde apoyo en todos los niveles de una organización, incluido el punto donde se presta la atención (consultorio o clínica), el sistema de atención de salud y a nivel regional, estatal y nacional. Se necesitan sistemas efectivos de detección y de alcance comunitario para encontrar a las personas sin diag- nóstico previo de hipertensión, así como un sistema para el seguimiento y la localización una vez han sido diagnosticadas. La aplicación de protocolos simples para tratar la hipertensión puede reducir la confusión entre los proveedores y aumentar la eficiencia del tratamiento. Garantizar un acceso fácil a medicamentos seguros, efectivos y asequibles puede aumentar el control de la presión arterial y potencialmente disminuir los costos para el sistema de atención de salud. La distribución de tareas entre los miembros del equipo de atención de salud permite expandir los servicios que se prestan. Finalmente, es necesario dar seguimiento al desempeño del equipo de atención de salud y presentar información al respecto, a fin de aprender de las buenas prácticas, difundir ideas entre quienes necesitan mejorar y determinar a cuáles pacientes se debe llegar y cuáles necesitan atención adicional. Los programas de hipertensión a gran escala con buenos resultados en diferentes entornos comparten muchos de estos elementos clave y sirven como ejemplos para mejorar la atención de la hipertensión en todo el mundo.


[RESUMO]. A hipertensão continua sendo a principal causa de doenças cardiovasculares no mundo, apesar da dis- ponibilidade de tratamentos seguros e eficazes. Infelizmente, existem muitas barreiras para o controle da hipertensão, incluindo a falta de rastreamento e a conscientização eficazes, a incapacidade de acesso ao tratamento e desafios de conduta clínica quando ela é tratada. A abordagem dessas barreiras é complexa e requer um enfoque sistemático e sustentado em diferentes comunidades ao longo do tempo. Esta análise tem como objetivo descrever os elementos-chave necessários para criar um sistema eficaz de prestação de intervenções para o controle da hipertensão. Um sistema de sucesso requer vontade política e liderança que o apoie em todos os níveis de uma organização, inclusive no ponto da prestação de cuidados (consultório ou clínica), no sistema de saúde e nos níveis regional, estadual e nacional. Sistemas eficazes de triagem e acolhida são necessários para identificar indivíduos com hipertensão não diagnosticada, e um sistema de acompanhamento e rastreamento após o diagnóstico se faz igualmente necessário. A implementação de protocolos simples para o tratamento da hipertensão pode reduzir a confusão entre os profissionais de saúde e aumentar a eficiência do tratamento. Garantir o fácil acesso a medicamentos seguros, eficazes e acessíveis pode aumentar o controle da pressão arterial e potencialmente diminuir os custos do sistema de saúde. A divisão de tarefas entre os integrantes da equipe de saúde pode expandir os serviços prestados. Finalmente, é necessário monitorar e informar acerca do desempenho da equipe de saúde para aprender com aqueles que estão indo bem, disseminar ideias para aqueles que precisam melhorar e identificar pacientes individuais que precisam de ajuda ou cuidados adicionais. Programas bem-sucedidos de controle da hipertensão em larga escala em diferentes ambientes compartilham muitos desses elementos-chave e servem como exem- plos para melhorar os sistemas de atenção à hipertensão em todo o mundo.


Asunto(s)
Hipertensión , Grupo de Atención al Paciente , Mejoramiento de la Calidad , Salud Poblacional , Gestión de la Salud Poblacional , Protocolos Clínicos , Programas de Detección Diagnóstica , Antihipertensivos , Hipertensión , Grupo de Atención al Paciente , Mejoramiento de la Calidad , Salud Poblacional , Gestión de la Salud Poblacional , Protocolos Clínicos , Programas de Detección Diagnóstica , Antihipertensivos , Hipertensión , Grupo de Atención al Paciente , Mejoramiento de la Calidad , Salud Poblacional , Gestión de la Salud Poblacional , Programas de Detección Diagnóstica , Antihipertensivos
2.
Rev. panam. salud pública ; 46: e153, 2022. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1431973

RESUMEN

ABSTRACT Hypertension remains the leading cause of cardiovascular disease globally despite the availability of safe and effective treatments. Unfortunately, many barriers exist to controlling hypertension, including a lack of effective screening and awareness, an inability to access treatment and challenges with its management when it is treated. Addressing these barriers is complex and requires engaging in a systematic and sustained approach across communities over time. This analysis aims to describe the key elements needed to create an effective delivery system for hypertension control. A successful system requires political will and supportive leadership at all levels of an organization, including at the point of care delivery (office or clinic), in the health care system, and at regional, state and national levels. Effective screening and outreach systems are necessary to identify individuals not previously diagnosed with hypertension, and a system for follow up and tracking is needed after people are diagnosed. Implementing simple protocols for treating hypertension can reduce confusion among providers and increase treatment efficiency. Ensuring easy access to safe, effective and affordable medications can increase blood pressure control and potentially decrease health care system costs. Task-sharing among members of the health care team can expand the services that are delivered. Finally, monitoring of and reporting on the performance of the health care team are needed to learn from those who are doing well, disseminate ideas to those in need of improvement and identify individual patients who need outreach or additional care. Successful large-scale hypertension programs in different settings share many of these key elements and serve as examples to improve systems of hypertension care delivery throughout the world.


RESUMEN A pesar de la disponibilidad de tratamientos seguros y efectivos, la hipertensión sigue siendo la principal causa de enfermedad cardiovascular a nivel mundial. Lamentablemente, el control de la hipertensión enfrenta muchos obstáculos, como la falta de detección y concientización efectivas, la incapacidad de acceder al tratamiento y los retos que plantea su manejo cuando se recibe tratamiento. Resulta complejo abordar estos obstáculos; se debe adoptar un enfoque sistemático y sostenido en todas las comunidades a lo largo del tiempo. El presente análisis tiene como objetivo describir los elementos clave necesarios para crear un sistema de atención eficaz para el control de la hipertensión. Un sistema adecuado precisa voluntad política y un liderazgo que brinde apoyo en todos los niveles de una organización, incluido el punto donde se presta la atención (consultorio o clínica), el sistema de atención de salud y a nivel regional, estatal y nacional. Se necesitan sistemas efectivos de detección y de alcance comunitario para encontrar a las personas sin diagnóstico previo de hipertensión, así como un sistema para el seguimiento y la localización una vez han sido diagnosticadas. La aplicación de protocolos simples para tratar la hipertensión puede reducir la confusión entre los proveedores y aumentar la eficiencia del tratamiento. Garantizar un acceso fácil a medicamentos seguros, efectivos y asequibles puede aumentar el control de la presión arterial y potencialmente disminuir los costos para el sistema de atención de salud. La distribución de tareas entre los miembros del equipo de atención de salud permite expandir los servicios que se prestan. Finalmente, es necesario dar seguimiento al desempeño del equipo de atención de salud y presentar información al respecto, a fin de aprender de las buenas prácticas, difundir ideas entre quienes necesitan mejorar y determinar a cuáles pacientes se debe llegar y cuáles necesitan atención adicional. Los programas de hipertensión a gran escala con buenos resultados en diferentes entornos comparten muchos de estos elementos clave y sirven como ejemplos para mejorar la atención de la hipertensión en todo el mundo.


RESUMO A hipertensão continua sendo a principal causa de doenças cardiovasculares no mundo, apesar da disponibilidade de tratamentos seguros e eficazes. Infelizmente, existem muitas barreiras para o controle da hipertensão, incluindo a falta de rastreamento e a conscientização eficazes, a incapacidade de acesso ao tratamento e desafios de conduta clínica quando ela é tratada. A abordagem dessas barreiras é complexa e requer um enfoque sistemático e sustentado em diferentes comunidades ao longo do tempo. Esta análise tem como objetivo descrever os elementos-chave necessários para criar um sistema eficaz de prestação de intervenções para o controle da hipertensão. Um sistema de sucesso requer vontade política e liderança que o apoie em todos os níveis de uma organização, inclusive no ponto da prestação de cuidados (consultório ou clínica), no sistema de saúde e nos níveis regional, estadual e nacional. Sistemas eficazes de triagem e acolhida são necessários para identificar indivíduos com hipertensão não diagnosticada, e um sistema de acompanhamento e rastreamento após o diagnóstico se faz igualmente necessário. A implementação de protocolos simples para o tratamento da hipertensão pode reduzir a confusão entre os profissionais de saúde e aumentar a eficiência do tratamento. Garantir o fácil acesso a medicamentos seguros, eficazes e acessíveis pode aumentar o controle da pressão arterial e potencialmente diminuir os custos do sistema de saúde. A divisão de tarefas entre os integrantes da equipe de saúde pode expandir os serviços prestados. Finalmente, é necessário monitorar e informar acerca do desempenho da equipe de saúde para aprender com aqueles que estão indo bem, disseminar ideias para aqueles que precisam melhorar e identificar pacientes individuais que precisam de ajuda ou cuidados adicionais. Programas bem-sucedidos de controle da hipertensão em larga escala em diferentes ambientes compartilham muitos desses elementos-chave e servem como exemplos para melhorar os sistemas de atenção à hipertensão em todo o mundo.

3.
Braz J Phys Ther ; 25(1): 97-102, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32499168

RESUMEN

OBJECTIVES: The aims of this study were to determine, in Australian pulmonary rehabilitation programs for people with COPD: (1) whether oxygen saturation (SpO2) was monitored during exercise testing; (2) whether supplemental oxygen was available during exercise testing and/or training; (3) whether oxygen was prescribed during exercise training; and the reason for providing oxygen; (4) whether a protocol was available for supplemental oxygen prescription during exercise training. METHODS: This was a cross-sectional multi-center study using a purposed-designed survey. De-identified survey data were analyzed and the absolute number and percentage of responses were recorded for each question. RESULTS: The survey was sent to 261 pulmonary rehabilitation programs and 142 surveys (54%) were available for analysis. Oxygen saturation was monitored during exercise testing in 92% of programs. Supplemental oxygen was available in the majority of programs during exercise testing (82%) and training (84%). The rationale cited by 87 programs (73%) for prescribing oxygen during exercise training was maintaining SpO2 above a threshold ranging from SpO2 80-88%. Forty-five (32%) programs had a protocol for oxygen prescription during exercise training. CONCLUSION: While monitoring of SpO2 during exercise testing and using supplemental oxygen during testing and training is common in Australian pulmonary rehabilitation programs, few programs had a protocol in place for the prescription of supplemental oxygen for people with COPD who were not on long-term oxygen therapy. This may be due to lack of strong evidence to support the use of supplemental oxygen during exercise training.


Asunto(s)
Terapia por Ejercicio/métodos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Australia , Estudios Transversales , Prueba de Esfuerzo , Tolerancia al Ejercicio , Humanos , Terapia por Inhalación de Oxígeno , Calidad de Vida
4.
J Clin Hypertens (Greenwich) ; 21(8): 1043-1056, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31301120

RESUMEN

This review aims to summarize and synthesize studies reporting on changes in sodium levels in packaged food products, restaurant foods, and hospital or school meals, as a result of salt reduction interventions. Studies were extracted from those published in the Science of Salt Weekly between June 2013 and February 2018. Twenty-four studies were identified: 17 assessed the changes in packaged foods, four in restaurant foods, two in hospital or school meals, and one in both packaged and restaurant foods. Three types of interventions were evaluated as part of the studies: voluntary reductions (including targets), labeling, and interventions in institutional settings. Decreases in sodium were observed in all studies (n = 8) that included the same packaged foods matched at two time points, and in the studies carried out in hospitals and schools. However, there was little to no change in mean sodium levels in restaurant foods. The pooled analysis of change in sodium levels in packaged foods showed a decrease in sodium in unmatched food products (-36 mg/100 g, 95% CI -51 to -20 mg/100 g) and in five food categories-breakfast cereals, breads, processed meats, crisps and snacks, and soups. Twenty-two of the 24 studies were from high-income countries, limiting the applicability of the findings to lower resource settings.


Asunto(s)
Ingredientes Alimentarios/análisis , Etiquetado de Alimentos/estadística & datos numéricos , Hipertensión/dietoterapia , Política Nutricional/legislación & jurisprudencia , Cloruro de Sodio Dietético/análisis , Australia/epidemiología , Brasil/epidemiología , Pan/análisis , Canadá/epidemiología , Estudios Transversales , Grano Comestible , Embalaje de Alimentos/métodos , Hospitales/estadística & datos numéricos , Humanos , Hipertensión/epidemiología , Hipertensión/prevención & control , India/epidemiología , Comidas/clasificación , Países Bajos/epidemiología , Nueva Zelanda/epidemiología , Restaurantes/estadística & datos numéricos , Instituciones Académicas/estadística & datos numéricos , Eslovenia/epidemiología , Cloruro de Sodio Dietético/provisión & distribución , Reino Unido/epidemiología , Estados Unidos/epidemiología
5.
J Pediatr ; 211: 179-184.e1, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31084917

RESUMEN

OBJECTIVES: To examine weight changes relative to surgical success in children with Down syndrome and obstructive sleep apnea (OSA). STUDY DESIGN: Retrospective chart review of children with Down syndrome undergoing tonsillectomy from 2005 to 2016 for OSA at a tertiary care children's hospital. Only patients with pre-and postoperative polysomnogram within 6 months of tonsillectomy were included. Demographics, weight, height, and polysomnogram data were collected. Body mass index (BMI), expressed as a percentage of the 95th percentile (%BMIp95), was calculated for 24 months prior to and following surgery. Pre-and postoperative OSA severity were also recorded. The postoperative obstructive/hypopnea index identified subjects with resolution of obstruction (obstructive/hypopnea index <2 events/hour) or persistent mild/moderate/severe obstructive apnea. Regression analyses were used to compare %BMIp95 pre- and post-tonsillectomy with %BMIp95 by OSA status following tonsillectomy. RESULTS: A total of 78 patients with Down syndrome whose mean age was 5.29 years at time of tonsillectomy were identified. There was no difference between best-fit curves of %BMI p95 pre-and post-tonsillectomy. There was no difference between best-fit curves of %BMI p95 in patients who saw resolution of OSA after tonsillectomy vs patients with residual OSA. CONCLUSIONS: Tonsillectomy neither alters the BMI trajectory of children with Down syndrome, nor changes differentially the risk for obesity in children whose OSA did or did not resolve after surgery.


Asunto(s)
Índice de Masa Corporal , Síndrome de Down/epidemiología , Obesidad Infantil/epidemiología , Tonsilectomía , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Análisis de Regresión , Estudios Retrospectivos , Apnea Obstructiva del Sueño/cirugía
6.
J Clin Hypertens (Greenwich) ; 21(6): 710-721, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31033166

RESUMEN

The Global Burden of Disease (GBD) 2010 study estimated national salt intake for 187 countries based on data available up to 2010. The purpose of this review was to identify studies that have measured salt intake in a nationally representative population using the 24-hour urine collection method since 2010, with a view to updating evidence on population salt intake globally. Studies published from January 2011 to September 2018 were searched for from MEDLINE, Scopus, and Embase databases using relevant terms. Studies that provided nationally representative estimates of salt intake among the healthy adult population based on the 24-hour urine collection were included. Measured salt intake was extracted and compared with the GBD estimates. Of the 115 identified studies assessed for eligibility, 13 studies were included: Four studies were from Europe, and one each from the United States, Canada, Benin, India, Samoa, Fiji, Barbados, Australia, and New Zealand. Mean daily salt intake ranged from 6.75 g/d in Barbados to 10.66 g/d in Portugal. Measured mean population salt intake in Italy, England, Canada, and Barbados was lower, and in Fiji, Samoa, and Benin was higher, in recent surveys compared to the GBD 2010 estimates. Despite global targets to reduce population salt intake, only 13 countries have published nationally representative salt intake data since the GBD 2010 study. In all countries, salt intake levels remain higher than the World Health Organization's recommendation, highlighting the need for additional global efforts to lower salt intake and monitor salt reduction strategies.


Asunto(s)
Conducta Alimentaria/etnología , Carga Global de Enfermedades/estadística & datos numéricos , Hipertensión/prevención & control , Cloruro de Sodio Dietético/orina , Toma de Muestras de Orina/métodos , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Barbados/epidemiología , Benin/epidemiología , Canadá/epidemiología , Europa (Continente)/epidemiología , Conducta Alimentaria/psicología , Femenino , Fiji/epidemiología , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , India/epidemiología , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Samoa/epidemiología , Cloruro de Sodio Dietético/efectos adversos , Estados Unidos/epidemiología , Organización Mundial de la Salud
7.
J Clin Sleep Med ; 12(6): 879-84, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27092702

RESUMEN

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a common pediatric condition characterized by recurrent partial or complete cessation of airflow during sleep, typically due to inadequate upper airway patency. Continuous positive airway pressure (CPAP) is a therapeutic option that reduces morbidity. Despite efforts to promote use, CPAP adherence is poor in both pediatric and adult populations. We sought to determine whether demographics, insurance status, OSA severity, therapeutic pressure, or comorbid conditions were associated with pediatric CPAP adherence. METHODS: A retrospective review of adherence download data was performed on all pediatric patients with initiation or adjustment of CPAP treatment over a one-year period with documented in-laboratory CPAP titration. Patients were grouped as CPAP adherent or non-adherent, where adherence was defined as > 70% nightly use and average usage ≥ 4 hours per night. Differences between the groups were analyzed by χ(2) test. RESULTS: Overall, nearly half of participants were CPAP adherent (49%, 69/140). Of the demographic data collected (age, ethnicity, sex, insurance status), only female sex was associated with better adherence (60.9% vs 39.5% of males adherent; odds ratio [OR] = 2.41, 95%CI = 1.20-4.85; p = 0.01). Severity of OSA (diagnostic apnea-hypopnea index [AHI] and degree of hypoxemia), therapeutic pressure, and residual AHI did not impact CPAP adherence (p > 0.05). Patients with developmental delay (DD) were more likely to be adherent with CPAP than those without a DD diagnosis (OR = 2.55, 95%CI = 1.27-5.13; p = 0.007). Female patients with trisomy 21 tended to be more adherent, but this did not reach significance or account for the overall increased adherence associated with female sex. CONCLUSIONS: Our study demonstrates that adherence to CPAP therapy is poor but suggests that female sex and developmental delay are associated with better adherence. These findings support efforts to understand the pathophysiology of and to develop adherence-promoting and alternative interventions for pediatric OSA.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Cooperación del Paciente/estadística & datos numéricos , Apnea Obstructiva del Sueño/terapia , Niño , Femenino , Humanos , Masculino , Polisomnografía , Estudios Retrospectivos
8.
ISME J ; 7(1): 50-60, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22832344

RESUMEN

The microbial mats of Guerrero Negro (GN), Baja California Sur, Mexico historically were considered a simple environment, dominated by cyanobacteria and sulfate-reducing bacteria. Culture-independent rRNA community profiling instead revealed these microbial mats as among the most phylogenetically diverse environments known. A preliminary molecular survey of the GN mat based on only ∼1500 small subunit rRNA gene sequences discovered several new phylum-level groups in the bacterial phylogenetic domain and many previously undetected lower-level taxa. We determined an additional ∼119,000 nearly full-length sequences and 28,000 >200 nucleotide 454 reads from a 10-layer depth profile of the GN mat. With this unprecedented coverage of long sequences from one environment, we confirm the mat is phylogenetically stratified, presumably corresponding to light and geochemical gradients throughout the depth of the mat. Previous shotgun metagenomic data from the same depth profile show the same stratified pattern and suggest that metagenome properties may be predictable from rRNA gene sequences. We verify previously identified novel lineages and identify new phylogenetic diversity at lower taxonomic levels, for example, thousands of operational taxonomic units at the family-genus levels differ considerably from known sequences. The new sequences populate parts of the bacterial phylogenetic tree that previously were poorly described, but indicate that any comprehensive survey of GN diversity has only begun. Finally, we show that taxonomic conclusions are generally congruent between Sanger and 454 sequencing technologies, with the taxonomic resolution achieved dependent on the abundance of reference sequences in the relevant region of the rRNA tree of life.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Agua de Mar/microbiología , Bacterias/genética , Biodiversidad , Cianobacterias/genética , Cianobacterias/aislamiento & purificación , Cianobacterias/fisiología , Genes de ARNr , Secuenciación de Nucleótidos de Alto Rendimiento , México , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
9.
Am J Forensic Med Pathol ; 32(3): 300-3, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20562690

RESUMEN

Judaism has many traditions, customs, rules, and laws, which relate to the proper and ethical disposition of a decedent when a Medical Examiner/ Coroner is involved. In almost all United States jurisdictions, statutes mandate the need to determine the cause and manner of death (Coroners' Act PA Pl. 323, num. 130, section 1237). This article is a review of some religious writings, legal precedents, and forensic authorities, which may help to assist the Medical Examiner/Coroner when confronted with a Jewish decedent. There can be flexibility as to the extent that such forensic studies can and should be performed. The final consent and interpretation of the rules, laws, traditions, and customs will rest with the courts and local rabbinic authority.


Asunto(s)
Autopsia/métodos , Medicina Legal/legislación & jurisprudencia , Judíos , Judaísmo , Médicos Forenses , Exhumación/legislación & jurisprudencia , Humanos , Israel , Imagen por Resonancia Magnética , Religión y Medicina , Consentimiento por Terceros/legislación & jurisprudencia , Tomografía por Rayos X
10.
Astrobiology ; 9(9): 861-74, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19968463

RESUMEN

Microbial mats in the hypersaline lake of Salt Pan, Eleuthera, Bahamas, display a gradient of lithification along a transect from the center to the shore of the lake. These mats exist under similar geochemical conditions, with light quantity and quality as the sole major environmental difference. Therefore, we hypothesized that the microbial community may be driving the differences in lithification and, by extension, mineral biosignature formation. The lithifying and non-lithifying mat communities were compared (via 16S rRNA gene sequencing, 485 and 464 sequences, respectively) over both temporal and spatial scales. Seven bacterial groups dominated in all the microbial mat libraries: bacteriodetes, alphaproteobacteria, deltaproetobacteria, chloroflexi, spirochaetes, cyanobacteria, and planctomycetes. The mat communities were all significantly different over space, time, and lithification state. Species richness is significantly higher in the non-lithifying mats, potentially due to differences in mat structure and activity. This increased richness may impact lithification and, hence, biosignature production.


Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Biodiversidad , Sedimentos Geológicos/microbiología , Salinidad , Bacterias/efectos de la radiación , Bahamas , Secuencia de Bases , Ambiente , Biblioteca de Genes , Geografía , Concentración de Iones de Hidrógeno , Luz , Consumo de Oxígeno/efectos de la radiación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Temperatura , Factores de Tiempo , Microbiología del Agua
11.
Environ Microbiol ; 11(10): 2710-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19601956

RESUMEN

Living marine stromatolites at Highborne Cay, Bahamas, are formed by microbial mat communities that facilitate precipitation of calcium carbonate and bind and trap small carbonate sand grains. This process results in a laminated structure similar to the layering observed in ancient stromatolites. In the modern marine system at Highborne Cay, lamination, lithification and stromatolite formation are associated with cycling between three types of microbial communities at the stromatolite surface (Types 1, 2 and 3, which range from a leathery microbial mat to microbially fused sediment). Examination of 923 universal small-subunit rRNA gene sequences from these communities reveals that taxonomic richness increases during transition from Type 1 to Type 3 communities, supporting a previous model that proposed that the three communities represent different stages of mat development. The phylogenetic composition also changes significantly between these community types and these community changes occur in concert with variation in biogeochemical rates. The dominant bacterial groups detected in the stromatolites include Alphaproteobacteria, Planctomycetes, Cyanobacteria and Bacteroidetes. In addition, the stromatolite communities were found to contain novel cyanobacteria that may be uniquely associated with modern marine stromatolites. The implications of these findings are discussed in the context of current models for stromatolite formation.


Asunto(s)
Bacterias/crecimiento & desarrollo , Biodiversidad , Sedimentos Geológicos/microbiología , Alphaproteobacteria/genética , Alphaproteobacteria/crecimiento & desarrollo , Alphaproteobacteria/aislamiento & purificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacteroidetes/genética , Bacteroidetes/crecimiento & desarrollo , Bacteroidetes/aislamiento & purificación , Bahamas , Cianobacterias/genética , Cianobacterias/crecimiento & desarrollo , Cianobacterias/aislamiento & purificación , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Genes de ARNr , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
12.
Appl Environ Microbiol ; 75(7): 1801-10, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19114531

RESUMEN

The Guerrero Negro (GN) hypersaline microbial mats have become one focus for biogeochemical studies of stratified ecosystems. The GN mats are found beneath several of a series of ponds of increasing salinity that make up a solar saltern fed from Pacific Ocean water pumped from the Laguna Ojo de Liebre near GN, Baja California Sur, Mexico. Molecular surveys of the laminated photosynthetic microbial mat below the fourth pond in the series identified an enormous diversity of bacteria in the mat, but archaea have received little attention. To determine the bulk contribution of archaeal phylotypes to the pond 4 study site, we determined the phylogenetic distribution of archaeal rRNA gene sequences in PCR libraries based on nominally universal primers. The ratios of bacterial/archaeal/eukaryotic rRNA genes, 90%/9%/1%, suggest that the archaeal contribution to the metabolic activities of the mat may be significant. To explore the distribution of archaea in the mat, sequences derived using archaeon-specific PCR primers were surveyed in 10 strata of the 6-cm-thick mat. The diversity of archaea overall was substantial albeit less than the diversity observed previously for bacteria. Archaeal diversity, mainly euryarchaeotes, was highest in the uppermost 2 to 3 mm of the mat and decreased rapidly with depth, where crenarchaeotes dominated. Only 3% of the sequences were specifically related to known organisms including methanogens. While some mat archaeal clades corresponded with known chemical gradients, others did not, which is likely explained by heretofore-unrecognized gradients. Some clades did not segregate by depth in the mat, indicating broad metabolic repertoires, undersampling, or both.


Asunto(s)
Archaea/clasificación , Archaea/aislamiento & purificación , Biodiversidad , Sedimentos Geológicos/microbiología , Archaea/genética , ADN de Archaea/química , ADN de Archaea/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genes de ARNr , México , Datos de Secuencia Molecular , Océano Pacífico , Filogenia , ARN de Archaea/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
13.
Hum Reprod Update ; 15(1): 69-95, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18945715

RESUMEN

BACKGROUND: Human chorionic gonadotrophin (hCG) is measured in serum and urine for the early detection of ectopic pregnancy, patients with higher risk of miscarriage, embryos or fetuses with chromosome abnormalities, prediction of pre-eclampsia or fetal growth restriction and identification or follow-up of trophoblast neoplasia. This review examines basic knowledge on the heterogeneity of hCG protein core and sugar branches and its relevance to assays used in a clinical setting. METHODS: The databases Scielo and Medline/Pubmed were consulted for identification of the most relevant published papers. Search terms were gonadotrophin, glycoprotein structure, hCG structure and molecular forms of hCG. RESULTS: The synthesis of alpha (hCGalpha) and beta (hCGbeta) peptide chains and their further glycosylation involve the complex action of different enzymes. After assembly, hCG reaches the cell surface and is secreted as a bioactive heterodimer. The complex cascade of enzymes acting in hCG secretion results in heterogeneous molecular forms. The hCG molecules are differently metabolized by the liver, ovary and kidney, but the majority of hCG forms are excreted in the urine. Intact hCG, hCGalpha, hCGbeta, hyperglycosylated (hCGh), nicked (hCGn) and core fragment of hCGbeta (hCGbetacf) forms have relevant clinical use. The immunogenicity of each hCG variant, their epitopes distribution and the available antibodies are important for the development of specific assays. Depending on the prevalent form or proportion in relation to the intact hCG, the choice of assay for measurement of a specific molecule in a particular clinical setting is paramount. CONCLUSIONS: Measurement of hCG and/or its related molecules is useful in clinical practice, but greater awareness is needed worldwide regarding the use of new sensitive and specific assays tailored for different clinical applications.


Asunto(s)
Gonadotropina Coriónica/química , Secuencia de Aminoácidos , Gonadotropina Coriónica/inmunología , Gonadotropina Coriónica/metabolismo , Gonadotropina Coriónica/fisiología , Femenino , Glicosilación , Humanos , Modelos Biológicos , Embarazo , Subunidades de Proteína/química , Análisis de Secuencia de Proteína , Transducción de Señal
14.
Appl Environ Microbiol ; 74(20): 6444-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18757573

RESUMEN

A phylogenetic comparison of microbial communities in hypersaline evaporites was conducted on crusts from Guerrero Negro, Mexico, and Lindsey Lake, New Mexico, using culture-independent rRNA gene sequence analysis. Many sequences were shared between evaporites, which suggests that similar environments select for specific microbial lineages from a global metacommunity.


Asunto(s)
Archaea/clasificación , Archaea/aislamiento & purificación , Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Microbiología Ambiental , Archaea/genética , Bacterias/genética , ADN de Archaea/química , ADN de Archaea/genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genes de ARNr , México , Datos de Secuencia Molecular , New Mexico , Filogenia , ARN de Archaea/genética , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
15.
Mol Syst Biol ; 4: 198, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18523433

RESUMEN

To investigate the extent of genetic stratification in structured microbial communities, we compared the metagenomes of 10 successive layers of a phylogenetically complex hypersaline mat from Guerrero Negro, Mexico. We found pronounced millimeter-scale genetic gradients that were consistent with the physicochemical profile of the mat. Despite these gradients, all layers displayed near-identical and acid-shifted isoelectric point profiles due to a molecular convergence of amino-acid usage, indicating that hypersalinity enforces an overriding selective pressure on the mat community.


Asunto(s)
Genética Microbiana , Salinidad , Selección Genética , Aminoácidos/metabolismo , México
16.
J Nat Prod ; 70(6): 954-61, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17552563

RESUMEN

Bioactivity-directed fractionation of an extract of the leaves of Alvaradoa haitiensis, using the KB (human oral epidermoid carcinoma) cell line, led to the isolation and identification of 10 new anthracenone C-glycosides, alvaradoins E-N (1-10), along with the known compound chrysophanol (11). The cytotoxicity of all compounds was evaluated, and preliminary structure-activity relationships are suggested. The most potent compounds in the in vitro assays (1 and 2) were evaluated in vivo versus the P388 (murine lymphocytic leukemia) model, and alvaradoin E (1) showed antileukemic activity (125% T/C) at a dose of 0.2 mg kg-1 per injection when administered intraperitoneally.


Asunto(s)
Antracenos/aislamiento & purificación , Antracenos/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Monosacáridos/aislamiento & purificación , Monosacáridos/farmacología , Plantas Medicinales/química , Simaroubaceae/química , Animales , Antracenos/química , Antineoplásicos Fitogénicos/química , República Dominicana , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Células KB , Leucemia P388 , Modelos Biológicos , Estructura Molecular , Monosacáridos/química , Hojas de la Planta/química , Relación Estructura-Actividad
17.
Appl Environ Microbiol ; 72(5): 3685-95, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16672518

RESUMEN

We applied nucleic acid-based molecular methods, combined with estimates of biomass (ATP), pigments, and microelectrode measurements of chemical gradients, to map microbial diversity vertically on a millimeter scale in a hypersaline microbial mat from Guerrero Negro, Baja California Sur, Mexico. To identify the constituents of the mat, small-subunit rRNA genes were amplified by PCR from community genomic DNA extracted from layers, cloned, and sequenced. Bacteria dominated the mat and displayed unexpected and unprecedented diversity. The majority (1,336) of the 1,586 bacterial 16S rRNA sequences generated were unique, representing 752 species (> or =97% rRNA sequence identity) in 42 of the main bacterial phyla, including 15 novel candidate phyla. The diversity of the mat samples differentiated according to the chemical milieu defined by concentrations of O(2) and H(2)S. Bacteria of the phylum Chloroflexi formed the majority of the biomass by percentage of bulk rRNA and of clones in rRNA gene libraries. This result contradicts the general belief that cyanobacteria dominate these communities. Although cyanobacteria constituted a large fraction of the biomass in the upper few millimeters (>80% of the total rRNA and photosynthetic pigments), Chloroflexi sequences were conspicuous throughout the mat. Filamentous Chloroflexi bacteria were identified by fluorescence in situ hybridization within the polysaccharide sheaths of the prominent cyanobacterium Microcoleus chthonoplastes, in addition to free living in the mat. The biological complexity of the mat far exceeds that observed in other polysaccharide-rich microbial ecosystems, such as the human and mouse distal guts, and suggests that positive feedbacks exist between chemical complexity and biological diversity. The sequences determined in this study have been submitted to the GenBank database and assigned accession numbers DQ 329539 to DQ 331020, and DQ 397339 to DQ 397511.


Asunto(s)
Bacterias , Ecosistema , Agua Dulce/microbiología , Cloruro de Sodio , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacteroidetes/clasificación , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Chloroflexi/clasificación , Chloroflexi/genética , Chloroflexi/aislamiento & purificación , Cianobacterias/clasificación , Cianobacterias/genética , Cianobacterias/aislamiento & purificación , Agua Dulce/química , Variación Genética , Hibridación Fluorescente in Situ , México , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Proteobacteria/clasificación , Proteobacteria/genética , Proteobacteria/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
18.
Anticancer Res ; 25(2A): 779-87, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15868909

RESUMEN

Two anthracenone C-glycosides, alvaradoins E and F, isolated from the leaves of Alvaradoa haitiensis Urb. (Simaroubaceae), were found to have potent inhibitory activities with cultured cancer cells. Using the in vivo hollow fiber model, these compounds demonstrated significant growth inhibition at the i.p. site when tested with KB, LNCaP, and Col2 cells. To determine if these anthracenone C-glycosides mediated anticancer activity through an apoptotic pathway, a series of assays were performed with the 10S isomeric compound, alvaradoin E. With a DAPI assay, treatment of LNCaP cells with alvaradoin E at concentrations of 0.4, 2, 10, or 50 microM for 24 or 48 h showed chromatin condensation, a morphological characteristic of apoptosis. Mitochondrial membrane potential, analyzed with a DiOC6 uptake assay, showed that treatment of LNCaP cells with 0.07, 0.14, 0.28, 0.56, 0.86, and 1.12 microM alvaradoin E for 12 h caused dose-dependent membrane depolarization, another indication of early apoptosis. Also, with an annexin V-FITC assay system, treatment of HL-60 cells with 0.07 microM alvaradoin E for 24 h increased annexin V-FITC binding from 3 to 25.9% (8.6-fold). Finally, with the TUNEL assay system, treatment of HL-60 cells with 1.12 microM alvaradoin E for 32 h increased FITC-dUTP binding from 1.2 to 12.1% (10-fold). These data suggest alvaradoin E is an effective anticancer agent that induces apoptosis. Additional studies to establish clinical utility should be of interest.


Asunto(s)
Antracenos/farmacología , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Monosacáridos/farmacología , Simaroubaceae/química , Anexina A5 , Antracenos/aislamiento & purificación , Línea Celular Tumoral , Núcleo Celular/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Citometría de Flujo , Fluoresceína-5-Isotiocianato , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Células HL-60 , Humanos , Etiquetado Corte-Fin in Situ , Indoles , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/fisiología , Células KB , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Mitocondrias/efectos de los fármacos , Mitocondrias/fisiología , Monosacáridos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Coloración y Etiquetado/métodos
19.
Psychon Bull Rev ; 12(6): 1054-60, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16615328

RESUMEN

We examined some potential causes of bias in geographic location estimates by comparing location estimates of North American cities made by Canadian, U.S., and Mexican university students. All three groups placed most Mexican cities near the equator, which implies that all three groups were influenced by shared beliefs about the locations of geographical regions relative to global reference points. However, the groups divided North America into different regions and differed in the relative accuracy of the estimates within them, which implies that there was an influence of culture-specific knowledge. The data support a category-based system of plausible reasoning, in which biases in judgments are multiply determined, and underscore the utility of the estimation paradigm as a tool in cross-cultural cognitive research.


Asunto(s)
Actitud/etnología , Cognición , Juicio , Canadá , Comparación Transcultural , Humanos , México , Estudiantes , Estados Unidos
20.
J Nat Prod ; 67(3): 352-6, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15043409

RESUMEN

Cytotoxicity-based, bioassay-guided fractionation of the chloroform-soluble extracts of both the roots and leaves of Picramnia latifolia led to the isolation of two new anthrone C-glycosides, picramniosides G (1) and H (2), two new oxanthrone C-glycosides, mayosides D (3) and E (4), and a new benzanthrone natural product, 6,8-dihydroxy-10-methyl-7H-benz[de]anthracen-7-one (5), together with 10 known compounds, 6,8-dihydroxy-4-methyl-7H-benz[de]anthracen-7-one (6), nataloe-emodin (7), chrysophanein, chrysophanol, 1,5-dihydroxy-7-methoxy-3-methylanthraquinone, pulmatin, 7-hydroxycoumarin, 7-hydroxy-6-methoxycoumarin, beta-sitosterol, and beta-sitosterol glucoside. The structures of 1-5 were established by spectroscopic methods, including 1D and 2D NMR, HRMS, and CD data interpretation. The cytotoxic activity of all isolates was evaluated in a small panel of human cancer cell lines. Compound 7 exhibited significant in vitro cytotoxic activity in the tested cell lines, but no significant activity was observed with an in vivo hollow fiber model at doses of 6.25, 12.5, 25, and 50 mg/kg/injection.


Asunto(s)
Antracenos/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Plantas Medicinales/química , Antracenos/química , Antracenos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Glicósidos/química , Glicósidos/farmacología , Humanos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Perú , Hojas de la Planta/química , Estereoisomerismo , Células Tumorales Cultivadas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA