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1.
Chemosphere ; 242: 125249, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896203

RESUMO

Machu Picchu is an archaeological Inca sanctuary from the 15th century, located 2430 m above the sea level in the Cusco Region, Peru. In 1983, it was declared World Heritage Site by UNESCO. The surroundings and soils from the entire archaeological site are carefully preserved together with its grass parks. Due to the importance of the archaeological city and its surroundings, the Decentralized Culture Directorate of Cusco-PAN Machu Picchu decided to carry out a careful monitoring study in order to determine the ecological status of the soils. In this work, elemental and molecular characterization of 17 soils collected along the entire park was performed by means of X-ray Diffraction (XRD) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after acidic digestion assisted by microwave energy. Thanks to the combination of these analytical techniques, it was possible to obtain the mineral composition and metal concentrations of all soils from these 17 sampling points. Finally, different statistical treatments were carried out in order to confirm the ecological status of the different sampling points from Machu Picchu archaeological site concluding that soils are not impacted.


Assuntos
Monitoramento Ambiental , Metais/análise , Poluentes do Solo/análise , Cidades , Metais Pesados/análise , Peru , Solo/química , Difração de Raios X
2.
Environ Sci Pollut Res Int ; 24(31): 24333-24345, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28889400

RESUMO

In city playgrounds, there is a potential risk of harming children's health by contamination coming from anthropogenic activities. With the aim to determinate the sources and the risk of hazardous elements, soil samples were collected in 19 selected playgrounds of different urban and rural areas from the Rio Grande do Sul state (Brazil). The concentration of 23 metals and metalloids and lead isotopic ratios were determined by ICP-MS. The methodology proposed here, firstly, classified the parks according to the average metal content by means of the NWACs (Normalized-and-Weighted Average Concentrations) and assess the contamination risk determining the Contamination Factors (CFs). Finally, statistical tools (correlation analysis and principal component analysis) were used to identify the most important contamination sources. The statistical tools used, together with lead isotopic composition analysis of the samples, revealed that coal combustion is the main source of contamination in the area. Vegetation was identified as a barrier for the contamination coming from the city. Nonetheless, some of the soils present a possible toxicological risk for humans. In fact, Cr, Sb, and Pb concentrations were higher than the Residential Intervention Values (VIRs) defined by the Environmental Protection Agency of the State of São Paulo, also in Brazil.


Assuntos
Exposição Ambiental , Monitoramento Ambiental , Metaloides/análise , Metais/análise , Poluentes do Solo/análise , Brasil , Criança , Humanos , Isótopos/análise , Chumbo/análise , Parques Recreativos , Medição de Risco
3.
Bol. malariol. salud ambient ; 54(2): 129-137, dic. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-740280

RESUMO

En la forma mucocutánea (LCM) y cutánea (LCL) de la leishmaniasis, se genera una respuesta inflamatoria cuyos mediadores (células y citocinas) se han involucrado en la severidad de las úlceras y en el daño tisular observado en estos pacientes, particularmente en los LCM. Por ello, nos propusimos identificar los grupos celulares predominantes en la secreción nasal de pacientes con LCL y LCM, y relacionarlos con citocinas proinflamatorias y reguladoras. Evaluamos en pacientes LCL (n=20), LCM (n=14) y 20 individuos sanos: a) La cuantificación de tipos de leucocitos en "frotis" de secreción nasal, úlceras cutáneas y sangre periférica teñidos con Giemsa empleando microscopía óptica, b) Concentraciones séricas de IL-8, IL-4 e IL-10 por citometría de flujo (CBA array) e IFN-γ, TNF-α e IL-17 por ELISA. El grupo celular predominante en la secreción nasal de pacientes con LCM fueron los neutrófilos (80,7%) y escasos eosinófilos (0,6%), comparados con los LCL y controles, en los que no se observaron estas células. Mientras que los "frotis" de las ulceras de los LCL presentaron 45,3% de neutrófilos y 43% de linfocitos. En contraste, en sangre periférica, de los pacientes se observó un incremento de neutrófilos y linfocitos junto a una frecuencia significativa de monocitos (LCM: 5,3; LCL: 6,3%) y eosinófilos (LCM: 8,2%; LCL: 5,2%). Todo esto sugiere la participación de los neutrófilos en la inmunopatogénesis en la LCM. Adicionalmente, se demostró una mayor (P=0,03) concentración sérica de IL-8 en los pacientes con LCL (18,5ρg/mL) y LCM (18,2ρg/mL) respecto a los individuos sanos, sugiriendo que esta citocina promueve el reclutamiento de neutrófilos al sitio de infección en los LCM, mientras que en los LCL contribuyen junto con los linfocitos T CD4+ de la subpoblación Th1 y productores de IFN-γ, en la activación de mecanismos leishmanicidas.


In mucocutaneous (MCL) and cutaneous (LCL) leishmaniasis, the inflammatory mediators (cytokines and cells) have been associated with ulcers severity and tissue damage observed in these patients, particularly in MCL. Therefore, we decided to identify the predominant cell groups in the nasal secretion of LCL and MCL patients, and related pro-inflammatory and regulatory cytokines. It was evaluated in LCL (n = 20), MCL patients (n = 14) and 20 healthy volunteers: a) Differential leukocyte count by optical microscopy performed in: smear of a runny nose, skin ulcers and peripheral blood dyed with Giemsa, b) serum levels of IL-8, IL-4 and IL-10 using cytometric bead array (CBA) assay and IFN-γ, TNF-α and IL-17 by ELISA. In MCL patients, neutrophils (80.7%) were the most abundant cellular group in nose secretion, followed by a small amount of eosinophils (0.6%) compared to the LCL and controls, where no such cells were observed. In contrast, in peripheral blood from ACL patients were observed an abundant amount of neutrophils and lymphocytes together with a significant frequency of monocytes (MCL:5.3%; LCL: 6.3%) and eosinophils (MCL:8.2%; LCL:5.2%). While the smear from skin ulcers of LCL patients showed 45.3% of neutrophils and 43% lymphocytes. All of these indicate that neutrophils might play a role in the MCL immunopathogenesis. Moreover, an increased serum levels of IL-8 (P=0.03) were found in LCL (18.5ρg/mL) and MCL (18.2ρg/mL) patients, suggesting that this cytokine promotes the recruitment of neutrophils to the infection site in MCL; while in LCL patients may contribute with CD4 + Th1 (IFN-γ) cells in the activation of leishmanicida mechanisms.

4.
Biomedica ; 28(3): 347-56, 2008 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-19034358

RESUMO

INTRODUCTION: Leishmaniases constitutes a serious public health problem in many parts of the Americas. However, the populations exposed to leishmaniasis lack information about this disease. For this reason, educational assessments and interventions were deemed necessary to contribute to a greater impact of control measures. OBJECTIVE: The level of knowledge and practices was evaluated for tegumentary leishmaniasis and the phlebotomine sand fly vector species. MATERIALS AND METHODS: Between September 2006 and July 2007, a survey was conducted on epidemiological aspects, prevention, and control of leishmaniasis in two endemic communities-Bolero Alto and Bajo, in the municipality of Pinto Salina, Mérida state, Venezuela. It was administered to persons 7 years of age, in randomly selected houses. Collections of sand fly vectors were made indoors and around the houses. RESULTS: Approximately 68% of the population showed a level of knowledge on leishmaniasis considered as insufficient. The lowest level of knowledge found was on matters related to leishmaniasis transmission and prevention. Seven epidemiologically important Lutzomyia species were identified: L. youngi, L. ovallesi, L. gomezi, L. walkeri, L. panamensis, L. punctigeniculata and L. venezuelensis. The predominant species in both communities were L. youngi and L. ovallesi, constituting 55% and 24%, respectively, of the totals. CONCLUSIONS: The residents of the endemic communities studied had a low level of knowledge about leishmaniasis. This must be considered in the development of educational alternatives that complement control programs. A particular focus on the prevention of insect bites is recommended.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Leishmaniose Cutânea/epidemiologia , Animais , Criança , Doenças Endêmicas/prevenção & controle , Feminino , Humanos , Insetos Vetores/fisiologia , Leishmaniose Cutânea/prevenção & controle , Leishmaniose Cutânea/transmissão , Masculino , Psychodidae/fisiologia , Venezuela/epidemiologia
5.
Biomédica (Bogotá) ; Biomédica (Bogotá);28(3): 347-356, sept. 2008. tab, graf
Artigo em Espanhol | LILACS | ID: lil-526141

RESUMO

Introducción. La leishmaniasis es un grave problema de salud pública en muchas partes de América. Las poblaciones expuestas a la leishmaniasis carecen de información de la enfermedad, razón por la cual es necesario realizar intervenciones y evaluaciones educativas que contribuyan a que el control tenga un mayor impacto. Objetivo. Determinar el nivel de conocimientos y prácticas sobre la leishmaniasis tegumentaria y la fauna de flebótomos en las comunidades endémicas de Bolero Alto y Bajo del municipio Pinto Salina del Estado Mérida, Venezuela, entre septiembre de 2006 y julio de 2007. Materiales y métodos. Se elaboró una encuesta en la cual se incluyeron aspectos epidemiológicos, de prevención y de control de la leishmaniasis. Se aplicaron a personas mayores de siete años en viviendas seleccionadas aleatoriamente. También se realizaron capturas intradomiciliarias y peridomiciliarias de flebotominos vectores. Resultados. Más del 68 por ciento de los individuos de las comunidades poseía un nivel de conocimientos considerado como insuficiente; los aspectos de mayor desconocimiento fueron en relación con la transmisión y la prevención. Se detectaron siete especies de Lutzomyia de importancia epidemiológica: L youngi, L. ovallesi, L. gomezi, L. walkeri, L. panamensis, L. punctigeniculata y L. venezuelensis. Las especies predominantes para ambas comunidades fueron L. youngi con más del 55 por ciento y L. ovallesi con más del 24 por ciento del total de especímenes capturados. Conclusión. Se determinó un bajo nivel de conocimientos sobre la leishmaniasis en los pobladores de las comunidades endémicas estudiadas, lo cual se debe tener en cuenta en el desarrollo de alternativas educativas de impacto en el control complementario de la enfermedad. Las mismas deben dirigirse a cubrir las deficiencias de conocimientos más acentuadas en la población, enfocadas a evitar las picaduras del insecto vector.


Assuntos
Vetores de Doenças , Conhecimentos, Atitudes e Prática em Saúde , Leishmaniose , Psychodidae
6.
Biomedica ; 26(1): 42-50, 2006 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-16929902

RESUMO

INTRODUCTION: Chagas disease and leishmaniasis are important public health problems due to their high frequency and broad distribution in Latin America. Understanding of the roles of reservoir animals is crucial for a global assessment of the epidemiology of these diseases. OBJECTIVE: To identify parasites classed as Trypanosomatidae as they occurred in sylvatic animals, and to establish rates of coinfection. MATERIALS AND METHODS: Sylvatic animals were systematically captured in the rural area of El Carrizal, Merida State, Venezuela, betweenJuly, 1998 and February, 2000. The captures were made in Tomahawk type homemade traps, placed 15 nights per month throughout the study period. Blood was extracted from each captured and anesthetized animal by means of cardiac puncture. The search for trypanosomatids was undertaken by fresh blood examination, Giemsa stained blood smears and by means of blood-agar culture. Occasional xenodiagnoses were made to check diagnostic accuracy. The isolates obtained in culture media were identified by restriction fragment analysis and hybridization with specific probes. RESULTS: Three species of sylvatic animals (n = 215) were captured: Rattus spp. (135), Sigmodon hispidus (73) and Didelphis marsupialis (7). From them, three species of Trypanosomatidae were identified: Leishmania (Viannia) guyanensis, Trypanosoma cruzi and Trypanosoma lewisi. Trypanosoma. cruzi was identified in D. marsupialis (4/7), S. hispidus (1/73) and Rattus spp. (1/ 135), whereas L. (V.) guyanensis and T. lewisi were identified only in Rattus spp., 1/135 and 12/ 135, respectively. CONCLUSIONS: The coexistence of these genetically related hemoflagellates in sylvatic hosts was important for understanding the immunological interactions that may be established in reservoir animals, and the possible implications that this may have for the susceptible host. Finally, the identification of L. (V.) guyanensis in Rattus spp and T. cruzi in S. hispidus constituted the first reports of this relationship in Venezuela.


Assuntos
Reservatórios de Doenças , Saúde Pública , Trypanosomatina/metabolismo , Animais , Doença de Chagas/sangue , Doença de Chagas/parasitologia , Humanos , Leishmania/genética , Leishmania/metabolismo , Leishmaniose/sangue , Leishmaniose/parasitologia , Gambás/sangue , Gambás/parasitologia , Ratos/sangue , Ratos/parasitologia , Sigmodontinae/sangue , Sigmodontinae/parasitologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/metabolismo , Trypanosoma lewisi/genética , Trypanosoma lewisi/metabolismo , Trypanosomatina/genética , Venezuela , Xenodiagnóstico , Zoonoses
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