RESUMO
For millennia, Maya farmers (i.e., milperos) throughout Mesoamerica have managed milpa: sequential agroforests initiated by slashing and burning patches of secondary forest and then cultivating a diverse polyculture of trees and annual crops. To reduce greenhouse gas emissions associated with deforestation, the Mexican government and non-governmental organizations have urged milperos to cease burning. We collaborated with Maya milperos in several communities in the Montes Azules Biosphere Reserve region in Chiapas, Mexico to determine carbon retained as char in traditional milpas, carbon loss associated with burning, and effects of burning on soil quality. We found the carbon retention of char in Maya milpas (24 ± 6.5% of C in vegetation) is 4-1400% higher than other slash-and-burn agroecosystems reported in the literature. Burning resulted in significant carbon loss of 12.6 (±3.6) t C ha-1 yr-1, but this was partially mitigated by char production (3.0 [±0.6] t C ha-1 yr-1) and incomplete combustion of woody biomass. The effects of burning on soil were minimal, with the only significant changes observed being increases in pH, potassium availability, and cation exchange capacity (2, 100, and 7%, respectively). The mean residence times of charred materials were at least double that of uncharred biomass. While there is a risk that shortening fallow periods would undermine the sustainability of Maya swidden agroecology, proper management and secure land tenure can help maintain intensive production without enduring environmental degradation. The char produced in these swiddens and successional management could allow this agroforestry system to be a long-term carbon sink.
Assuntos
Florestas , Solo , México , Árvores , Carbono , AgriculturaRESUMO
Gonadal sex differentiation in teleost fish shows greater plasticity as compared to other vertebrates, as it can be influenced by a variety of factors such as exogenous sex steroids. Exogenous estrogens, such as 17ß-estradiol (E2), can induce feminization when administered during early embryonic development. However, the mechanisms underlying the E2-induced feminization are not fully understood, especially in Neotropical species. Therefore, the aim of this study was to evaluate the effects of E2 administration on the phenotypic sex characteristics, histological assessment of the gonads, and the expression of selected genes in Astyanax altiparanae exposed to dietary E2 prior to gonadal differentiation. At 4 days post-hatch (dph), groups of 30-40 undifferentiated larvae were fed with a diet containing varying amounts of E2 for 28 days, and fish were sampled at 90 dph. Previous studies revealed that ovary formation in A. altiparanae occurred at 58 dph, whereas the first sign of testis formation was found at 73 dph. In relation to the control, E2 exposure increased the proportion of phenotypic females in 120% and 148.4% for 4 and 6 mg E2/Kg, respectively. However, histological analysis revealed that treatments did not affect gonadal sex ratio between males and females, but induced intersex (testis-ova) in the group treated with 6 mg E2/Kg food. Treatment with E2 also altered gonadal transcript levels of a selected number of genes implicated in sexual differentiation. Males overexpressed dmrt1, sox9 and amh following E2 treatment as compared to control. Females showed increased mRNA levels of dmrt1 and sox9, which might be related to the down-regulation of cyp19a1a after E2 exposure. In summary, E2 exposure during early gonadal development affected male secondary characteristics without changing the gonadal sex ratio, and altered expression of genes implicated in sexual differentiation.
Assuntos
Characidae/crescimento & desenvolvimento , Characidae/genética , Estradiol/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/crescimento & desenvolvimento , Animais , Characidae/metabolismo , Feminino , Proteínas de Peixes/biossíntese , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Larva/efeitos dos fármacos , Masculino , Razão de Masculinidade , América do SulRESUMO
BACKGROUND AND PURPOSE: The 2018 AHA guidelines recommend perfusion imaging to select patients with acute large vessel occlusion (LVO) for thrombectomy in the extended window. However, the relationship between noncontrast CT and CT perfusion imaging has not been sufficiently characterized >6 hours after last known normal (LKN). METHODS: From a multicenter prospective cohort of consecutive adults who underwent thrombectomy for anterior LVO 0-24 hours after LKN, we correlated baseline core volume (rCBF < 30%) and the Alberta Stroke Program Early CT Scale (ASPECTS) score. We compared perfusion findings between patients with an unfavorable ASPECTS (<6) against those with a favorable ASPECTS (≥6), and assessed findings over time. RESULTS: Of 485 enrolled patients, 177 met inclusion criteria (median age: 69 years, interquartile range [IQR: 57-81], 49% female, median ASPECTS 8 [IQR: 6-9], median core 10 cc [IQR: 0-30]). ASPECTS and core volume moderately correlated (r = -.37). A 0 cc core was observed in 54 (31%) patients, 70% of whom had ASPECTS <10. Of the 28 patients with ASPECTS <6, 3 (11%) had a 0 cc core. After adjustment for age and stroke severity, there was a lower ASPECTS for every 1 hour delay from LKN (cOR: 0.95, 95% confidence of interval [CI]: 0.91-1.00, P = .04). There was no difference in core (P = .51) or penumbra volumes (P = .87) across patients over time. CONCLUSIONS: In this multicenter prospective cohort of patients who underwent thrombectomy, one-third of patients had normal CTP core volumes despite nearly three quarters of patients showing ischemic changes on CT. This finding emphasizes the need to carefully assess both noncontrast and perfusion imaging when considering thrombectomy eligibility.
Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem de Perfusão/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Alberta , Pressão Sanguínea/fisiologia , Isquemia Encefálica/terapia , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Trombectomia/métodosRESUMO
Understanding the profile of oncogene and tumor suppressor gene mutations with their interactions and impact on the prognosis of multiple myeloma (MM) can improve the definition of disease subsets and identify pathways important in disease pathobiology. Using integrated genomics of 1273 newly diagnosed patients with MM, we identified 63 driver genes, some of which are novel, including IDH1, IDH2, HUWE1, KLHL6, and PTPN11 Oncogene mutations are significantly more clonal than tumor suppressor mutations, indicating they may exert a bigger selective pressure. Patients with more driver gene abnormalities are associated with worse outcomes, as are identified mechanisms of genomic instability. Oncogenic dependencies were identified between mutations in driver genes, common regions of copy number change, and primary translocation and hyperdiploidy events. These dependencies included associations with t(4;14) and mutations in FGFR3, DIS3, and PRKD2; t(11;14) with mutations in CCND1 and IRF4; t(14;16) with mutations in MAF, BRAF, DIS3, and ATM; and hyperdiploidy with gain 11q, mutations in FAM46C, and MYC rearrangements. These associations indicate that the genomic landscape of myeloma is predetermined by the primary events upon which further dependencies are built, giving rise to a nonrandom accumulation of genetic hits. Understanding these dependencies may elucidate potential evolutionary patterns and lead to better treatment regimens.
Assuntos
Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/genética , Mutagênese , Oncogenes , Células Clonais , Análise Mutacional de DNA , DNA de Neoplasias/genética , Conjuntos de Dados como Assunto , Dosagem de Genes , Estudo de Associação Genômica Ampla , Instabilidade Genômica , Genômica , Humanos , Perda de Heterozigosidade , Mieloma Múltiplo/patologia , Mutação , Prognóstico , Translocação Genética , Resultado do Tratamento , Sequenciamento do ExomaRESUMO
ABSTRACT Background: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease predominantly affecting the older population. Not well known, COPD is often confused with asthma. Tobacco smoking is widely acknowledged as the most important risk factor for COPD, but occupational exposures from irritant dust, fumes and, biomass exposures from burning wood and coal indoors, also contribute to COPD prevalence. This paper looks at COPD prevalence and occupational exposures in adults aged 70+ using data from the United Kingdom-based Burden of Obstructive Lung Disease (BOLD) study in Jamaica (www.boldstudy.org). Subject and Method: Jamaica followed a strict BOLD protocol of face to face standardized questionnaire administration and spirometry testing on participants aged ≥ 40 years. Questions included sociodemographic characteristics, smoking practices, respiratory symptoms and occupational exposures. The Occupational questionnaire enquired about time spent in thirteen different occupations including farming, construction, firefighting, domestic and industrial cleaning, welding, coal mining, flour, feed or grain milling to mention a few. Spirometry was performed according to American Thoracic Society (ATS) standards. An island-wide multi-stage random sample of non-institutionalized individuals was selected for recruitment with the assistance of the Statistical Institute of Jamaica (STATIN). All questionnaires and spirometry data from consenting participants were submitted electronically to the United Kingdom Coordinating Centre for data cleaning, quality checks and preliminary analysis. Final data were returned to the local research team for further analysis. Result: Total sample selected for recruitment (and response rate) was 883 (91.4%) for persons aged ≥ 40 years and 190 (87.2%) for persons aged 70+ years. Of the 164 responders in the 70+ group, 91 (55.5%) had usable spirometry. Prevalence of ever-smoking by age and gender in this 70+ cohort was 38.4%. Farming, construction and household cleaning were the most frequently reported occupations (58.8%). Years working in these three occupations ranged from 1-70 (farming and construction) and 1-78 (cleaning). Most were now retired (120 of 164 overall). Weighted estimated population prevalence of Global Initiative for Chronic Obstructive Lung Disease (GOLD) Stage 1 (Post-BD FEV1/FVC < 70%; FEV1 ≥ 80% predicted) was 12.1% overall for persons aged 40+, but was highest at 37.8% in the 70+ age group. Estimated prevalence of GOLD Stage 2 (50 ≤ FEV1 < 80% predicted) was 9.6% in the 40+, again highest at 31.3% in the 70+ age group. Conclusion: Overall prevalence of COPD in the 40+ age group whether Stage 1 (mild COPD), or Stage 2 (moderate COPD), while it appears low, was still highest in the 70+ age group. The local data revealed that whilst the prevalence of current smoking had declined by age 70+, the estimated prevalence of GOLD Stage 1 and Stage 2 COPD was highest in this age group. The contribution of occupational exposures to the development of COPD, requires further analysis to look at the occupational exposures across all participants aged 40+ as well as the prevalence of COPD among non-smokers. Progression of Stage 1 to Stage 2 disease and its effect on morbidity and quality of life is likely without patient education regarding complications of tobacco smoke and workplace exposures to the development of COPD.
RESUMEN Antecedentes: La enfermedad pulmonar obstructiva crónica (EPOC) es una enfermedad respiratoria crónica que afecta predominantemente a la población de personas mayores. Como no se la conoce bien, la EPOC se confunde a menudo con el asma. El tabaquismo es ampliamente reconocido como el factor de riesgo más importante de la EPOC, pero las exposiciones profesionales a polvos irritantes, humos y gases, así como las exposiciones a la biomasa de leña y carbón en espacios cerrados, contribuyen a la prevalencia de la EPOC. El presente trabajo examina la prevalencia de la EPOC y las exposiciones ocupacionales en adultos de 70+ años, utilizando en Jamaica datos del estudio de la Carga de la Enfermedad Pulmonar Obstructiva (BOLD, en inglés) con base en el Reino Unido (www.boldstudy.org). Sujetos y método: Jamaica siguió un estricto protocolo de BOLD consistente en administrar cara a cara cuestionarios estandarizados y pruebas de espirometría a participantes de ≥ 40 años de edad. Las preguntas incluyeron características sociodemográficas, prácticas de tabaquismo, síntomas respiratorios y exposiciones ocupacionales. El cuestionario ocupacional indagó sobre el tiempo transcurrido en trece ocupaciones diferentes, incluyendo trabajo en el campo (agricultura, cría de animales) construcción, extinción de incendios, limpieza doméstica e industrial, soldadura, minería de carbón, y molienda de harina, piensos o granos, por mencionar algunas. La espirometría se realizó de acuerdo con las normas de la Sociedad Torácica Americana (STA). Se seleccionó una muestra aleatoria multietapa de todo el país -formada por individuos no institucionalizados— para el reclutamiento con la ayuda del Instituto Estadístico de Jamaica (STATIN, en inglés). Todos los cuestionarios y datos de espirometría de los participantes consintientes fueron enviados electrónicamente al Centro Coordinador del Reino Unido para la depuración de datos, chequeo de calidad y análisis preliminar. Los datos finales fueron devueltos al equipo de investigación local para su posterior análisis. Resultado: La muestra total seleccionada para el reclutamiento (y la tasa de respuesta) fue de 883 (91.4%) para las personas de ≥ 40 años y 190 (87.2%) para las personas de 70+ años. De los 164 encuestados en grupo de 70+ años, 91 (55.5%) tenían espirometría utilizable. La prevalencia de fumar ocasionalmente por edad y sexo en esta cohorte de 70+ fue de 38.4%. El trabajo en el campo (agricultura, cría de animales), la construcción y la limpieza doméstica fueron las ocupaciones más frecuentemente reportadas (58.8%). Los años de trabajo en estas tres ocupaciones oscilaron entre 1-70 (trabajo en el campo y construcción), y 1-78 (limpieza). La mayoría estaban ahora retirados (120 de 164 en total). La prevalencia ponderada estimada de la población de la Iniciativa Global para la Enfermedad Pulmonar Obstructiva Crónica (GOLD, en inglés) Etapa 1 (post-BD FEV1/FVC < 70%; FEV1 ≥ 80% valor teórico) fue de 12.1% en total para las personas de 40+, pero las más alta fue 37.8% en el grupo de 70+ años. La prevalencia estimada de GOLD Etapa 2 (50 ≤ FEV1 < 80% valor teórico) fue de 9.6% en los de 40+, y de nuevo 31.3% la más alta en el grupo de 70+ años de edad. Conclusión: La prevalencia general de la EPOC en el grupo de 40+ años, ya fuera en la etapa 1 (EPOC leve), o la etapa 2 (EPOC moderada), aunque pareciera baja, seguía siendo más alta en el grupo de 70+ años. Los datos locales revelaron que si bien la prevalencia de fumar regularmente había disminuido a la edad de 70+, la prevalencia estimada de EPOC en GOLD Etapa 1 y Etapa 2 fue mayor en este grupo etario. La contribución de las exposiciones ocupacionales al desarrollo de la EPOC requiere un análisis adicional para examinar las exposiciones ocupacionales en todos los participantes de 40+ años. así como la prevalencia de la EPOC entre los no fumadores. La progresión de la enfermedad de la etapa 1 a la etapa 2 y su efecto sobre la morbilidad y la calidad de vida es probable que tenga lugar si no hay educación del paciente con respecto a las complicaciones que el humo del tabaco y las exposiciones en el centro de trabajo tienen para el desarrollo de la EPOC.
Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Tabagismo/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Poluentes Ocupacionais do Ar/efeitos adversos , Tabagismo/epidemiologia , Prevalência , Fatores de Risco , Doença Pulmonar Obstrutiva Crônica/etiologia , Jamaica/epidemiologiaRESUMO
Western North America is a region defined by extreme gradients in geomorphology and climate, which support a diverse array of ecological communities and natural resources. The region also has extreme gradients in mercury (Hg) contamination due to a broad distribution of inorganic Hg sources. These diverse Hg sources and a varied landscape create a unique and complex mosaic of ecological risk from Hg impairment associated with differential methylmercury (MeHg) production and bioaccumulation. Understanding the landscape-scale variation in the magnitude and relative importance of processes associated with Hg transport, methylation, and MeHg bioaccumulation requires a multidisciplinary synthesis that transcends small-scale variability. The Western North America Mercury Synthesis compiled, analyzed, and interpreted spatial and temporal patterns and drivers of Hg and MeHg in air, soil, vegetation, sediments, fish, and wildlife across western North America. This collaboration evaluated the potential risk from Hg to fish, and wildlife health, human exposure, and examined resource management activities that influenced the risk of Hg contamination. This paper integrates the key information presented across the individual papers that comprise the synthesis. The compiled information indicates that Hg contamination is widespread, but heterogeneous, across western North America. The storage and transport of inorganic Hg across landscape gradients are largely regulated by climate and land-cover factors such as plant productivity and precipitation. Importantly, there was a striking lack of concordance between pools and sources of inorganic Hg, and MeHg in aquatic food webs. Additionally, water management had a widespread influence on MeHg bioaccumulation in aquatic ecosystems, whereas mining impacts where relatively localized. These results highlight the decoupling of inorganic Hg sources with MeHg production and bioaccumulation. Together the findings indicate that developing efforts to control MeHg production in the West may be particularly beneficial for reducing food web exposure instead of efforts to simply control inorganic Hg sources.
Assuntos
Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Vertebrados/metabolismo , Animais , Canadá , Monitoramento Ambiental , Poluentes Ambientais/análise , Peixes/metabolismo , Mercúrio/análise , Compostos de Metilmercúrio/análise , México , Estados UnidosRESUMO
OBJECTIVE: To identify distinct trajectories of health-related quality of life (HRQOL) during childhood, along with their predictors. STUDY DESIGN: A nationally representative sample of 2700 children aged 4-5 years at baseline was followed up every 24 months through to age 12-13 years. Parents reported the children's HRQOL and data on potential predictors at each wave (5 in total) as part of the Longitudinal Study of Australian Children. RESULTS: Growth mixture modeling identified 5 distinct trajectories of HRQOL during childhood. Eighty-five percent of children had consistently high levels of HRQOL from age 4-5 years to 12-13 years (healthy); 8% of children had a significant and continuous decrease in HRQOL over time (high risk); and a further 5.3% of children had decreases in HRQOL from age 4-5 years to 8-9 years, followed by increases through to 12-13 years (rebound). Finally, a small percentage (1.6%) of children had extremely low levels of HRQOL at age 4-5 years that increased over time (recovery). Maternal smoking, lower household income, living in a non-English speaking household, and nonparticipation in organized sports were predictive of poorer HRQOL trajectories when compared with children in the healthy trajectory. CONCLUSION: There are distinct trajectories of HRQOL during childhood. Most children (85%) have a healthy, stable pattern, but the remaining children have trajectories indicative of poor HRQOL. Participation in sports, maternal smoking, lower family income, and language spoken at home distinguish among these trajectories. Of these, participation in organized sports has received relatively little attention as a preventative health priority.
Assuntos
Nível de Saúde , Qualidade de Vida , Adolescente , Fatores Etários , Austrália , Criança , Pré-Escolar , Saúde da Família , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco , Fatores SocioeconômicosRESUMO
OBJECTIVE: To investigate the longitudinal association between sports participation and parent-reported health-related quality of life (HRQOL) in children. STUDY DESIGN: Cohort study that used data drawn from the Longitudinal Study of Australian Children in waves 3 (2008) and 4 (2010). Participants were a nationally representative sample of 4042 Australian children ages 8.25 (SD = 0.44) years at baseline and followed-up 24 months later. RESULTS: After we adjusted for multiple covariates, children who continued to participate in sports between the ages of 8 and 10 years had greater parent-reported HRQOL at age 10 (Eta2 = .02) compared with children who did not participate in sports (P ≤ .001), children who commenced participation after 8 years of age (P = .004), and children who dropped out of sports before reaching 10 years of age (P = .04). Children who participated in both team and individual sports (P = .02) or team sports alone (P = .04) had greater HRQOL compared with children who participated in individual sports alone (Eta2 = .01). The benefits of sports participation were strongest for girls (P < .05; Eta2 = .003). CONCLUSIONS: Children's participation in developmentally appropriate team sports helps to protect HRQOL and should be encouraged at an early age and maintained for as long as possible.
Assuntos
Promoção da Saúde , Atividade Motora/fisiologia , Qualidade de Vida , Esportes/psicologia , Austrália , Índice de Massa Corporal , Criança , Proteção da Criança , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Relações Pais-Filho , Fatores Socioeconômicos , Esportes/fisiologiaRESUMO
This ISAAC Phase Three synthesis provides summarised information on the main findings of the study, regional tables and figures related to the prevalence and severity of current symptoms of asthma, rhinoconjunctivitis and eczema in the main regions of the world. The large number of surveyed children (≈1,200,000), the large number of centres (233) and countries (98) that participated in ISAAC Phase Three makes this study the most comprehensive survey of these diseases ever undertaken. Globally, the prevalence for current asthma, rhinoconjunctivitis and eczema in the 13-14-year age group was 14.1%, 14.6% and 7.3%, respectively. In the 6-7-year age group the prevalence for current asthma, rhinoconjunctivitis and eczema was 11.7%, 8.5% and 7.9%, respectively. The study shows a wide variability in the prevalence and severity of asthma, rhinoconjunctivitis and eczema which occurs not just between regions and countries but between centres in the same country and centres in the same city. This study definitively establishes that the prevalence of those diseases can be very high in non-affluent centres with low socioeconomic conditions. The large variability also suggests a crucial role of local environment characteristics to determine the differences in prevalence between one place and another. Thus, ISAAC Phase Three has provided a large body of epidemiological information on asthma, rhinoconjunctivitis and eczema in childhood from contrasting environments which is expected to yield new clues about the aetiology of those conditions and reasons for their marked global variability.
Assuntos
Asma/epidemiologia , Padrões de Prática Médica/estatística & dados numéricos , Fatores Socioeconômicos , Adolescente , Criança , Progressão da Doença , Feminino , Humanos , Cooperação Internacional , Masculino , Prevalência , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: Human immunodeficiency virus (HIV) is a serious disease which can be associated with various activity limitations and participation restrictions. The aim of this paper was to describe how HIV affects the functioning and health of people within different environmental contexts, particularly with regard to access to medication. METHOD: Four cross-sectional studies, three in South Africa and one in Brazil, had applied the International Classification of Functioning, Disability and Health (ICF) as a classification instrument to participants living with HIV. Each group was at a different stage of the disease. Only two groups had had continuing access to antiretroviral therapy. The existence of these descriptive sets enabled comparison of the disability experienced by people living with HIV at different stages of the disease and with differing access to antiretroviral therapy. RESULTS: Common problems experienced in all groups related to weight maintenance, with two-thirds of the sample reporting problems in this area. Mental functions presented the most problems in all groups, with sleep (50%, 92/185), energy and drive (45%, 83/185), and emotional functions (49%, 90/185) being the most affected. In those on long-term therapy, body image affected 93% (39/42) and was a major problem. The other groups reported pain as a problem, and those with limited access to treatment also reported mobility problems. Cardiopulmonary functions were affected in all groups. CONCLUSION: Functional problems occurred in the areas of impairment and activity limitation in people at advanced stages of HIV, and more limitations occurred in the area of participation for those on antiretroviral treatment. The ICF provided a useful framework within which to describe the functioning of those with HIV and the impact of the environment. Given the wide spectrum of problems found, consideration could be given to a number of ICF core sets that are relevant to the different stages of HIV disease.
Assuntos
Antirretrovirais/uso terapêutico , Avaliação da Deficiência , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Especialidade de Fisioterapia/métodos , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/psicologia , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , África do Sul/epidemiologiaRESUMO
Indigenous groups have designed and managed their ecosystems for generations, resulting in biodiversity protection while producing for their family's needs. Here we describe the agroecosystem of the Lacandon Maya, an indigenous group who live in Chiapas, Mexico. The Lacandon practice a form of swidden agriculture that conserves the surrounding rain forest ecosystem while cycling the majority of their land through five successional stages. These stages include an herbaceous stage, two shrub stages, and two forest stages. A portion of their land is kept in primary forest. This study presents the Lacandon traditional ecological knowledge (TEK) for agroforestry and quantitatively describes the plant community and the associated soil ecology of each successional stage. Also documented is the knowledge of the Lacandon regarding the immediate use of plant species and plant species useful for soil fertility enhancement. Woody plant diversity increases during the successional stages of the Lacandon system, and by the beginning of the first forest stage, the diversity is similar to that of the primary forest. In all stages, Lacandon use 60% of the available plant species for food, medicine, and raw materials. Approximately 45% of the woody plant species present in each fallow stage were thought by the Lacandon to enhance soil fertility. Total soil nitrogen and soil organic matter increased with successional stage and with time from intentional burn. Nutrient and soil nematode dynamics in shrub stages related to the presence of introduced and managed plants, indicating engineered soil enhancement by the Lacandon. The effects on biodiversity and soil ecology coupled with productivity for agricultural subsistence indicate that Lacandon TEK may offer tools for environmental conservation that would provide for a family's basic needs while maintaining a biodiverse rain forest ecosystem. Tools such as these may offer options for regional restoration and conservation efforts such as the Mesoamerican Biological Corridor in Mexico and Central America, where attainment of environmental goals must include methods to provide resources to local inhabitants.
Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , América Central , Monitoramento Ambiental , Humanos , Plantas/classificação , Plantas/metabolismo , Grupos Populacionais , SoloRESUMO
Pulmonary hypertension (PH) is defined as a systolic pulmonary artery pressure (PAP) above 30 mmHg and a mean PAP above 25 mmHg. Pulmonary hypertensive diseases (PHDs) encompass a myriad of conditions that cause pulmonary hypertension (PH), hence the Evian Classification was developed for the categorization of the various causes. Pulmonary hypertensive diseases are complex conditions that are difficult to treat and in the case of primary pulmonary hypertension, there is no known cure. Dyspnoea on exertion is the main symptom. This usually worsens as the disease progresses and can lead to syncope as a result of right ventricular failure. Prostacyclin has been the mainstay of treatment for decades, but several new drugs and alternate methods of treatment are currently available.
La hipertensión pulmonar (HP) se define como presión arterial pulmonar sistólica (PAP) por encima de 30 mmHg y una PAP por encima de 25 mmHg. Las enfermedades hipertensivas pulmonares (EHPs) comprenden un sinnúmero de condiciones que causan hipertensión pulmonar (HP), razón por la cual fue desarrollada la Clasificación de Evian para la categorización de las diversas causas. Las enfermedades pulmonares hipertensivas son condiciones complejas que son difíciles de tratar y en el caso de la hipertensión pulmonar primaria, no se conoce cura. La disnea al realizar un esfuerzo es el síntoma principal. Esta condición por lo regular empeora a medida que la enfermedad progresa, y puede llevar al síncope como resultado del fallo del ventrículo derecho. Durante décadas, la prostaciclina ha sido el soporte principal del tratamiento, pero varios medicamentos nuevos y métodos de tratamiento alternativos se hallan disponibles en el presente.
Assuntos
Humanos , Hipertensão Pulmonar , Progressão da Doença , Hipertensão Pulmonar/classificação , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/terapiaRESUMO
Pulmonary hypertension (PH) is defined as a systolic pulmonary artery pressure (PAP) above 30 mmHg and a mean PAP above 25 mmHg. Pulmonary hypertensive diseases (PHDs) encompass a myriad of conditions that cause pulmonary hypertension (PH), hence the Evian Classification was developed for the categorization of the various causes. Pulmonary hypertensive diseases are complex conditions that are difficult to treat and in the case of primary pulmonary hypertension, there is no known cure. Dyspnoea on exertion is the main symptom. This usually worsens as the disease progresses and can lead to syncope as a result of right ventricular failure. Prostacyclin has been the mainstay of treatment for decades, but several new drugs and alternate methods of treatment are currently available.
Assuntos
Hipertensão Pulmonar , Progressão da Doença , Humanos , Hipertensão Pulmonar/classificação , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/terapiaRESUMO
Constructed wetlands offer a low-cost wastewater treatment option for tropical developing countries. The vast majority of published treatment wetland research has been conducted in temperate regions. Because the function of treatment wetlands is related to the environmental conditions, more research specific to the tropics should be completed. A six-cell free water surface (FWS) wetland mesocosm was constructed in Santa Rosa de Copán, Honduras that received input from an open-sewer/wastewater-impacted stream. Three cells were planted with Typha domingensis Pers., and three cells were left unplanted. Both planted and unplanted wetlands were constructed with three different surface areas to concurrently study different hydraulic retention times (HRTs) and hydraulic loading rates (HLRs). Results from 6 months of operation showed improved water quality and mosquito larvae populations affected by their specific environment. Five-day biochemical oxygen demand (BOD) removal appeared to be proportional to HRT and HLR, and BOD concentration in the effluent was higher in unplanted cells than in planted cells (P<0.05). BOD removal approached 60% for greater than 3.5 days HRT. Total phosphorus (P) removal and coliform bacteria removal were found to be correlated with pollutant load, and P removal was found to be correlated with HRT but not HLR. A second municipal wastewater FWS treatment wetland in Copán Ruinas, Honduras that had been established for 15 years, was also evaluated. BOD removal in the Copán Ruinas system was determined to be 93% with 2.6 day HRT. These pollutant removal rates are higher than would be expected in temperate regions. Mosquito larvae density was correlated with depth of the wetland. Mosquito larvae densities were higher in cells that were operating below design depth of 0.2 m (P<0.005). Results indicate that it is possible to design FWS wetlands in the tropics for effective BOD removal and reduced mosquito larvae development.
Assuntos
Culicidae , Controle de Mosquitos/métodos , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/isolamento & purificação , Animais , Eichhornia , Enterobacteriaceae/isolamento & purificação , Honduras , Larva , Fósforo/isolamento & purificação , Clima Tropical , TyphaceaeRESUMO
BACKGROUND: The ratio between the length of the 2nd or index finger and the 4th or ring finger (2D:4D) differs between the sexes, such that males have lower 2D:4D than females, and shows considerable ethnic differences, with low values found in Black populations. It has been suggested that the sex difference in 2D:4D arises early in development and that finger ratio is a correlate of prenatal testosterone and oestrogen. In children, 2D:4D has been reported to be associated with measures of fetal growth, congenital adrenal hyperplasia, developmental psychopathology, autism and Asperger's syndrome. However, little is known of the patterns of sex and ethnic differences in the 2D:4D ratio of children. AIM: To investigate sex and ethnic differences in 2D:4D in Caucasian, Oriental and Black children. STUDY DESIGN: Population survey. METHOD: The 2D:4D ratio was measured from photocopies of the right hand of Berber children from Morocco, Uygur and Han children from the North-West province of China, and children from Jamaica. RESULTS: There were 798 children in the total sample (90 Berbers, 438 Uygurs, 118 Han, and 152 Jamaicans). The 2D:4D ratio was lower in males than in females and this was significant for the overall sample and for the Uygur, Han and Jamaican samples. There were significant ethnic differences in 2D:4D. The Oriental Han had the highest mean 2D:4D, followed by the Caucasian Berbers and Uygurs, with the lowest mean ratios found in the Afro-Caribbean Jamaicans. The sex and ethnic differences were independent of one another with no significant interaction effect. In the overall sample there were no associations between 2D:4D and age and height. CONCLUSIONS: In common with adults, the 2D:4D ratio of children shows sex and ethnic differences with low values found in a Black group. There was no overall association between 2D:4D and age and height suggesting that the sex and ethnic differences in 2D:4D appear early and do not show appreciable change with growth.
Assuntos
Antropometria , Pesos e Medidas Corporais/classificação , Etnicidade , Dedos/anatomia & histologia , Caracteres Sexuais , Criança , Pré-Escolar , China/etnologia , Feminino , Dedos/crescimento & desenvolvimento , Humanos , Jamaica/etnologia , Masculino , Marrocos/etnologiaRESUMO
Flavonols are polyphenolic secondary plant metabolites that are present in varying levels in commonly consumed fruits, vegetables and beverages. Flavonols have long held an interest for nutritionists, which has increased following a Dutch study in the early 1990's showing that dietary intake of flavonols was inversely correlated with the incidence of coronary heart disease. The main factors that have hindered workers in the field of flavonol research are (i) the accurate measurement of these compounds in foods and biological samples, and (ii) a dearth of information on their absorption and metabolism. This review aims to highlight the work of the authors in attempting to clarify the situation. The sensitive and selective HPLC procedure to identify and quantify common flavonols and their sugar conjugates is described. In addition, the results of an on-going screening program into the flavonol content of common produce and beverages are presented. The bioavailability of dietary flavonols is discussed with reference to an intervention study with onions, as well as pilot studies with tea, red wine and cherry tomatoes. It is concluded that flavonols are absorbable and accumulate in plasma and that consuming high flavonol-containing varieties of fruits and vegetables and particular types of beverages could increase their circulatory levels.
Assuntos
Antioxidantes/análise , Bebidas/análise , Flavonas/farmacocinética , Flavonóis/farmacocinética , Frutas/química , Verduras/química , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Flavonas/química , Flavonóis/química , Análise de Alimentos , Humanos , Fatores de TempoRESUMO
Flavonols are polyphenolic secondary plant metabolites that are present in varying levels in commonly consumed fruits, vegetables and beverages. Flavonols have long held an interest for nutritionists, which has increased following a Dutch study in the early 1990's showing that dietary intake of flavonols was inversely correlated with the incidence of coronary heart disease. The main factors that have hindered workers in the field of flavonol research are (i) the accurate measurement of these compounds in foods and biological samples, and (ii) a dearth of information on their absorption and metabolism. This review aims to highlight the work of the authors in attempting to clarify the situation. The sensitive and selective HPLC procedure to identify and quantify common flavonols and their sugar conjugates is described. In addition, the results of an on-going screening program into the flavonol content of common produce and beverages are presented. The bioavailability of dietary flavonols is discussed with reference to an intervention study with onions, as well as pilot studies with tea, red wine and cherry tomatoes. It is concluded that flavonols are absorbable and accumulate in plasma and that consuming high flavonol-containing varieties of fruits and vegetables and particular types of beverages could increase their circulatory levels.
Assuntos
Humanos , Antioxidantes/análise , Bebidas/análise , Flavonas/farmacocinética , Flavonóis/farmacocinética , Frutas/química , Plantas/química , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Flavonas/química , Flavonóis/química , Fatores de TempoRESUMO
A postmenopausal woman admitted to Bayview Hospital for total abdominal hysterectomy for uterine leiomyoma had unusual frond-like vascular excrescences on the anterior wall. These were biopsied, a subtotal hysterectomy was subsequently performed and cotyledonous leiomyoma, a rare and unusual form of uterine leiomyoma, was diagnosed. The macroscopic and microscopic features were presented.(AU)
Assuntos
Relatos de Casos , Feminino , Humanos , Leiomioma/diagnóstico , Neoplasias Uterinas/diagnóstico , Histerectomia , Modalidades de Secreções e Excreções , BiópsiaRESUMO
OBJECTIVE: To determine whether prophylactic, low dose controlled-release aspirin improves outcome for pregnant women and their babies in Barbados. DESIGN: Randomised placebo-controlled trial. SETTING: The Queen Elizabeth Hospital, Barbados. POPULATION: All women attending antenatal clinics between 12 and 32 weeks of gestation were eligible, if without specific contraindications to aspirin and unlikely to deliver immediately. METHODS: Randomisation was computer-generated in the antenatal clinic; 1822 women were allocated to receive 75 mg controlled-release aspirin and 1825 matching placebo. MAIN OUTCOME MEASURES: Proteinuric pre-eclampsia, other pregnancy-induced hypertension, pregnancy duration, birthweight, stillbirths and neonatal deaths, major neonatal events. RESULTS: All but three women from each group were followed up successfully. Forty-four percent were primigravid, and 8% had previous obstetric complications. There were no significant differences between the allocated treatment groups in the incidence of proteinuric pre-eclampsia (40 [2.2%] of those allocated aspirin, compared with 46 [2.5%] allocated placebo), of preterm delivery (255 [14.0%] vs 270 [14.8%]), of birthweight < 1500 g (32 [1.7%] vs 33 [1.8%]) or of stillbirth and neonatal death (44 [2.4%] vs 38 [2.1%]). Aspirin was not associated with excess risk of maternal or fetal bleeding. CONCLUSIONS: The results of this study in Barbados do not support the routine use of low dose aspirin for prevention of pre-eclampsia or its complications, confirming results of previous large trials in other settings.
PIP: The effect of administration of a prophylactic dose of controlled-release aspirin on the prevention of pre-eclampsia was investigated in a randomized placebo-controlled trial conducted at the Queen Elizabeth Hospital in Barbados in 1992-94. All women attending hospital antenatal clinics between 12 and 32 weeks of gestation were eligible for the study; enrolled were 1822 cases allocated to receive 75 mg of aspirin per day and 1825 matched controls who received a placebo. Study participants represented about 60% of women who gave birth during the enrollment period. Aspirin administration was not associated with any excessive risk of infant or maternal bleeding. However, there were no significant differences between cases and controls in terms of the incidence of proteinuric pre-eclampsia (2.2% vs. 2.5%), preterm delivery (14.0% vs. 14.8%), birth weight under 1500 g (1.7% vs. 1.8%), or stillbirth and neonatal death (2.4% vs. 2.1%). These results were not affected by the time of pregnancy at which aspirin prophylaxis was initiated or parity. The Barbados findings are consistent with previous studies and fail to support the routine use of low-dose aspirin for the prevention of pre-eclampsia and its complications.
Assuntos
Aspirina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Pré-Eclâmpsia/prevenção & controle , Adulto , Barbados/epidemiologia , Peso ao Nascer , Preparações de Ação Retardada , Feminino , Morte Fetal , Idade Gestacional , Hospitalização , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal , Fatores de TempoRESUMO
The epidemiology of Helicobacter pylori infection in Barbadian patients and controls was studied. H. pylori was isolated from biopsies from 50/100 (50 percent) adult patients undergoing endoscopy for investigation of upper gastrointestinal tract symptoms. Urease was detected in biopsies from 54 patients and gastritis was detected by histology in 71 patients. Serology was performed using a commercial ELISA method. Using an IgG concentration of 10 U/ml as a threshold, antibodies were detected in 78 percent of 100 patients undergoing endoscopy, 72 percent of 230 blood donors and 22 percent of 50 children. The mean antibody concentration was significantly higher in patients (92 U/ml) than in blood donors (49 U/ml) or in children (9.5 U/ml). Culture-positive patients (120 U/ml) had higher IgG concentration than culture-negative patients (64 U/ml). Using isolation of H. pylori or a positive biopsy urease test as a measure of true prevalence of infection, the sensitivity of serology was 96 percent, the specificity 42 percent positive predictive value 67 percent and negative predictive value 90 percent. Seroprevalence increased with age, to a peak of more than 90 percent in blood donors aged 50 - 59 years and in patients aged over 60 years. The epidemiology of H. pylori in Barbados is similar to that in developed countries, where few children was infected, but resembles other developing countries in the high seroprevalence observed in middle-aged adults.