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1.
Conserv Biol ; 38(2): e14176, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37668112

RESUMO

Biodiversity continues to decline despite protected area expansion and global conservation commitments. Biodiversity losses occur in existing protected areas, yet common methods used to select protected areas ignore postimplementation threats that reduce effectiveness. We developed a conservation planning framework that considers the ongoing anthropogenic threats within protected areas when selecting sites and the value of planning for costly threat-mitigating activities (i.e., enforcement) at the time of siting decisions. We applied the framework to a set of landscapes that contained the range of possible correlations between species richness and threat. Accounting for threats and implementing enforcement activities increased benefits from protected areas without increasing budgets. Threat information was valuable in conserving more species per spending level even without enforcement, especially on landscapes with randomly distributed threats. Benefits from including threat information and enforcement were greatest when human threats peaked in areas of high species richness and were lowest where human threats were negatively associated with species richness. Because acquiring information on threats and using threat-mitigating activities are costly, our findings can guide decision-makers regarding the settings in which to pursue these planning steps.


Anticipación de las amenazas antropogénicas durante la adquisición de áreas protegidas nuevas Resumen La biodiversidad sigue declinando a pesar de la expansión de áreas protegidas y los compromisos mundiales con la conservación. La pérdida de la biodiversidad ocurre en las áreas protegidas existentes, y todavía los métodos comunes usados para seleccionar las áreas protegidas ignoran las amenazas posteriores a la implementación, las cuales reducen la efectividad. Desarrollamos un marco de planeación de la conservación que considera las amenazas antropogénicas actuales dentro de las áreas protegidas durante la selección de sitios y el valor de la planeación de actividades mitigantes costosas, como la aplicación, al momento de decidir. Aplicamos nuestro marco a un conjunto de paisajes que comprende el rango de correlaciones posibles entre las amenazas y la riqueza de especies. Si consideramos las amenazas y la implementación de actividades de aplicación, los beneficios de las áreas protegidas incrementan sin incrementar el presupuesto. La información sobre las amenazas fue importante para la conservación de especies por nivel de gasto incluso sin la aplicación, especialmente en paisajes con amenazas distribuidas de forma azarosa. Los beneficios de incluir la información sobre las amenazas y la aplicación fueron mayores cuando las amenazas humanas llegaron a su tope en áreas con gran riqueza de especies y alcanzaron su punto más bajo cuando las amenazas humanas estaban asociadas negativamente con la riqueza de especies. Ya que es costoso adquirir información sobre las amenazas y mitigar las amenazas con actividades, nuestros descubrimientos pueden informar a los tomadores de decisiones con respecto al entorno para seguir los pasos de la planeación.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Humanos , Ecossistema
2.
Respir Res ; 15: 74, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24980707

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs) and C-reactive protein (CRP) are involved in chronic obstructive pulmonary disease (COPD) pathogenesis. The aim of the present work was to determine plasma concentrations of MMPs and CRP in COPD associated to biomass combustion exposure (BE) and tobacco smoking (TS). METHODS: Pulmonary function tests, plasma levels of MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP were measured in COPD associated to BE (n = 40) and TS (n =40) patients, and healthy non-smoking (NS) healthy women (controls, n = 40). RESULTS: Plasma levels of MMP-1, MMP-7, MMP-9, and MMP-9/TIMP-1 and CRP were higher in BE and TS than in the NS healthy women (p <0.01). An inverse correlation between MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP plasma concentrations and FEV1 was observed. CONCLUSIONS: Increase of MMPs and CRP plasma concentrations in BE suggests a systemic inflammatory phenomenon similar to that observed in COPD associated to tobacco smoking, which may also play a role in COPD pathogenesis.


Assuntos
Proteína C-Reativa/metabolismo , Volume Expiratório Forçado/fisiologia , Metaloproteinase 1 da Matriz/sangue , Metaloproteinase 7 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Fumar/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomassa , Feminino , Óleos Combustíveis/efeitos adversos , Humanos , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumaça/efeitos adversos , Fumar/efeitos adversos , Fumar/epidemiologia
3.
Acta Trop ; 205: 105422, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32112720

RESUMO

The reptile-associated Borrelia represent a monophyletic group of bacteria transmitted by several species of hard ticks, which has been reported to only infect amphibians and reptiles in Eurasia and Middle East, however, this bacterial group has not been studied in North America. The aim of this study was to assess the presence of Borrelia spirochetes in blood samples of native reptiles of Mexico. Blood samples were directly obtained from individuals, DNA extractions were performed using Chelex-100. The Borrelia detection was performed by conventional PCR. From 102 reptiles tested, only five individuals of Boa constrictor were positive for the presence of DNA of the reptile-associated Borrelia group. Supported by phylogenetic analysis, this study presents the first record of these spirochetes group in Mexico, and initial evidence of B. constrictor as a host of this group.


Assuntos
Boidae/microbiologia , Infecções por Borrelia/veterinária , Borrelia/genética , Animais , Borrelia/classificação , Infecções por Borrelia/epidemiologia , Infecções por Borrelia/microbiologia , Ixodidae/microbiologia , México , Filogenia , Reação em Cadeia da Polimerase
4.
PLoS One ; 14(1): e0210890, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30682061

RESUMO

We explored the hypothesis that high ß-diversity of terrestrial vertebrates of Mexico is associated with a high environmental heterogeneity (HEH) and identify the drivers of ß-diversity at different spatial scales. We used distribution range maps of 2,513 species of amphibians, reptiles, mammals, and birds occurring in Mexico. We estimated ß-diversity for each taxon at four spatial scales (grid cells of 2°, 1°, 0.5° and 0.25°) using the multiplicative formula of Whittaker ßw. For each spatial scale, we derived 10 variables of environmental heterogeneity among cells based on raw data of temperature, precipitation, elevation, vegetation and soil. We applied conditional autoregressive models (CAR) to identify the drivers of ß-diversity for each taxon at each spatial scale. CARs increased in explanatory power from fine-to-coarse spatial scales in amphibians, reptiles and mammals. The heterogeneity in precipitation including both, coefficient of variation (CV) and range of values (ROV), resulted in the most important drivers of ß-diversity of amphibians; the heterogeneity in temperature (CV) and elevation (ROV) were the most important drivers of ß-diversity for reptiles; the heterogeneity in temperature (ROV) resulted in the most important driver in ß-diversity for mammals. For birds, CARs resulted significant at fine scales (grid cells of 0.5° and 0.25°), and the precipitation (ROV and CV), temperature (ROV), and vegetation (H) and soil (H) were heterogeneity variables retained in the model. We found support for the hypothesis of environmental heterogeneity (HEH) for terrestrial vertebrates at coarse scales (grid cell of 2°). Different variables of heterogeneity, mainly abiotic, were significant for each taxon, reflecting physiological differences among terrestrial vertebrate groups. Our study revealed the importance of mountain areas in the geographic patterns of ß-diversity of terrestrial vertebrates in Mexico. At a coarse scale, specific variables of heterogeneity can be used as a proxy of ß-diversity for amphibians and reptiles.


Assuntos
Biodiversidade , Ecossistema , Vertebrados , Altitude , Anfíbios , Animais , Aves , Clima , Geografia , Mamíferos , México , Modelos Biológicos , Répteis , Temperatura
6.
Respir Med ; 105(11): 1648-54, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21763119

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a progressive disorder characterized by an inflammatory response to cigarette smoke. A disorder in immune regulation contributing to the pathogenesis of COPD has been suggested, however, little is known about the involvement of CD4 (+) T cells. To determine the distribution of different CD4(+) T cell subsets in patients with COPD, current smokers without COPD (CS) and healthy subjects (HS), and its correlation with pulmonary function. METHODS: Th1, Th2, Th17 and Treg, subsets, were quantified by flow cytometry in peripheral blood (PB) of 39 patients with COPD, 14 CS and 15 HS. Correlations were assessed with Spearman's rank test. The association between Th17 and lung function was evaluated with a multivariate logistic regression analysis. RESULTS: An increase of Th17 cells (median 9.7% range 0.8-22.5%) was observed in patients with COPD compared with CS (median 2.8% range 0.8-10.6) and HS (median 0.6% range 0.4-1%, p < 0.0001). Th1 and Tregs subsets were also increased in COPD and CS compared to HS. Inverse correlations were found between Th17 with FEV(1)%p r = -0.57 and with FEV(1)/FVC r = -0.60, (p < 0.0001 for both comparison). In addition, increase of Th17 predicted the presence [OR 1.76 (CI 95% 1.25-2.49, p = 0.001)] and severity of airflow limitation [OR 1.13 (CI95% 1.02-1.25, p = 0.02)]. CONCLUSIONS: The increase of Th17 response and the lost of balance between CD4(+) T cell subsets, suggest a lack of regulation of the systemic inflammatory response that may contribute to pathogenesis in COPD patients.


Assuntos
Interleucina-17/metabolismo , Pulmão/imunologia , Ativação Linfocitária/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Fumar/imunologia , Células Th17/metabolismo , Idoso , Feminino , Citometria de Fluxo , Humanos , Modelos Logísticos , Pulmão/fisiopatologia , Masculino , México/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/fisiopatologia , Espirometria
7.
PLoS One ; 4(9): e6878, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19721719

RESUMO

Traditionally, biodiversity conservation gap analyses have been focused on governmental protected areas (PAs). However, an increasing number of social initiatives in conservation (SICs) are promoting a new perspective for analysis. SICs include all of the efforts that society implements to conserve biodiversity, such as land protection, from private reserves to community zoning plans some of which have generated community-protected areas. This is the first attempt to analyze the status of conservation in Latin America when some of these social initiatives are included. The analyses were focused on amphibians because they are one of the most threatened groups worldwide. Mexico is not an exception, where more than 60% of its amphibians are endemic. We used a niche model approach to map the potential and real geographical distribution (extracting the transformed areas) of the endemic amphibians. Based on remnant distribution, all the species have suffered some degree of loss, but 36 species have lost more than 50% of their potential distribution. For 50 micro-endemic species we could not model their potential distribution range due to the small number of records per species, therefore the analyses were performed using these records directly. We then evaluated the efficiency of the existing set of governmental protected areas and established the contribution of social initiatives (private and community) for land protection for amphibian conservation. We found that most of the species have some proportion of their potential ecological niche distribution protected, but 20% are not protected at all within governmental PAs. 73% of endemic and 26% of micro-endemic amphibians are represented within SICs. However, 30 micro-endemic species are not represented within either governmental PAs or SICs. This study shows how the role of land conservation through social initiatives is therefore becoming a crucial element for an important number of species not protected by governmental PAs.


Assuntos
Conservação dos Recursos Naturais/métodos , Anfíbios , Animais , Animais Selvagens , Biodiversidade , Mudança Climática , Ecossistema , Monitoramento Ambiental/métodos , Geografia , Humanos , México , Modelos Biológicos , Dinâmica Populacional , Política Pública
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