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1.
Pathogens ; 13(8)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39204273

RESUMEN

Elucidation of pathways regulating parasite cell death is believed to contribute to identification of novel therapeutic targets for protozoan diseases, and in this context, apoptosis-like cell death has been reported in different groups of protozoa, in which metacaspases seem to play a role. In the genus Plasmodium, apoptotic markers have been detected in P. falciparum and P. berghei, and no study focusing on P. vivax cell death has been reported so far. In the present study, we investigated the susceptibility of P. vivax to undergo apoptotic cell death after incubating mature trophozoites with the classical apoptosis inducer staurosporine. As assessed by flow cytometry assays, staurosporine inhibited parasite intraerythrocytic development, which was accompanied by a decrease in cell viability, evidenced by reduced plasmodial mitochondrial activity. However, typical signs of apoptosis, such as DNA fragmentation, chromatin condensation, and nuclear segregation, were not detected in the parasites induced to cell death, and no significant alteration in metacaspase gene expression (PvMCA1) was observed under cell death stimulus. Interestingly, dying parasites positively modulated cell death (eryptosis) of host erythrocytes, which was marked by externalization of phosphatidylserine and cell shrinkage. Our study shows for the time that P. vivax blood stages may not be susceptible to apoptosis-like processes, while they could trigger eryptosis of parasitized cells by undergoing cell death. Further studies are required to elucidate the cellular machinery involved in cell death of P. vivax parasites as well as in the modulation of host cell death.

2.
Mol Biol Rep ; 51(1): 594, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38683374

RESUMEN

BACKGROUND: Metacaspases comprise a family of cysteine proteases implicated in both cell death and cell differentiation of protists that has been considered a potential drug target for protozoan parasites. However, the biology of metacaspases in Plasmodium vivax - the second most prevalent and most widespread human malaria parasite worldwide, whose occurrence of chemoresistance has been reported in many endemic countries, remains largely unexplored. Therefore, the present study aimed to address, for the first time, the expression pattern of metacaspases in P. vivax parasites. METHODS AND RESULTS: P. vivax blood-stage parasites were obtained from malaria patients in the Brazilian Amazon and the expression of the three putative P. vivax metacaspases (PvMCA1-3) was detected in all isolates by quantitative PCR assay. Of note, the expression levels of each PvMCA varied noticeably across isolates, which presented different frequencies of parasite forms, supporting that PvMCAs may be expressed in a stage-specific manner as previously shown in P. falciparum. CONCLUSION: The detection of metacaspases in P. vivax blood-stage parasites reported herein, allows the inclusion of these proteases as a potential candidate drug target for vivax malaria, while further investigations are still required to evaluate the activity, role and essentiality of metacaspases in P. vivax biology.


Asunto(s)
Malaria Vivax , Plasmodium vivax , Proteínas Protozoarias , Plasmodium vivax/genética , Plasmodium vivax/aislamiento & purificación , Brasil , Humanos , Malaria Vivax/parasitología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Caspasas/genética , Caspasas/metabolismo , Expresión Génica/genética
3.
Microorganisms ; 10(5)2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35630348

RESUMEN

Signal regulatory protein α (SIRPα) is an immunoreceptor expressed in myeloid innate immune cells that signals for inhibition of both phagocytosis and inflammatory response. Malaria parasites have evolutionarily selected multiple mechanisms that allow them to evade host immune defenses, including the modulation of cells belonging to innate immunity. Notwithstanding, little attention has been given to SIRPα in the context of immunosuppressive states induced by malaria. The present study attempted to investigate if malaria parasites are endowed with the capacity of modulating the expression of SIRPα on cells of innate immune system. Human peripheral blood mononuclear cells (PBMC) from healthy individuals were incubated in the presence of lipopolysaccharide (LPS) or crude extracts of P. falciparum or P. vivax and then, the expression of SIRPα was evaluated by flow cytometry. As expected, LPS showed an inhibitory effect on the expression of SIRPα in the population of monocytes, characterized by cell morphology in flow cytometry analysis, while Plasmodium extracts induced a significant positive modulation. Additional phenotyping of cells revealed that the modulatory potential of Plasmodium antigens on SIRPα expression was restricted to the population of monocytes (CD14+CD11c+), as no effect on myeloid dendritic cells (CD14-CD11c+) was observed. We hypothesize that malaria parasites explore inhibitory signaling of SIRPα to suppress antiparasitic immune responses contributing to the establishment of infection. Nevertheless, further studies are still required to better understand the role of SIRPα modulation in malaria immunity and pathogenesis.

4.
Mem Inst Oswaldo Cruz ; 116: e200584, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34076074

RESUMEN

In the present study, we investigated the genetic diversity of Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain in two municipalities of the main malaria hotspot in Brazil, i.e., the Juruá Valley, and observed complete sequence identity among all P. vivax field isolates and the Sal-1 reference strain. Analysis of PvMCA1 catalytic domain in different P. vivax genomic sequences publicly available also revealed a high degree of conservation worldwide, with very few amino acid substitutions that were not related to putative histidine and cysteine catalytic residues, whose involvement with the active site of protease was herein predicted by molecular modeling. The genetic conservation presented by PvMCA1 may contribute to its eligibility as a druggable target candidate in vivax malaria.


Asunto(s)
Malaria Vivax , Plasmodium vivax , Brasil , Dominio Catalítico , Variación Genética/genética , Humanos , Plasmodium vivax/genética , Proteínas Protozoarias/genética
5.
Front Oncol ; 10: 570233, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33117699

RESUMEN

INTRODUCTION: Immune checkpoint inhibitor-related pneumonitis (ICIP) is a potentially life threatening immune-related adverse event (irAE), especially in non-small cell lung cancer (NSCLC) patients. Currently, the potential for increased irAE in patients who receive radiotherapy is scarcely known, although a connection between antitumor immune responses and irAEs has been suggested. In this study, we evaluated the development of ICIP in non-small cell lung cancer patients with prior radiotherapy, treated with immunotherapy in the second-line. METHODS: In this retrospective trial, we included patients treated with second-line immunotherapy at the National Cancer Institute in Mexico City from February 2015 to February 2018. Clinical, radiological and treatment variables were evaluated according to the presence of ICIP as defined by the Common Terminology Criteria for Adverse Events (4.0) in patients with or without a previous (≥months) history of radiotherapy. RESULTS: Among 101 NSCLC patients who received treatment with ICIs, 22 patients (21.8%) were diagnosed with ICIP, of which 73% (16/22) had a history of radiotherapy (OR 6.04, 95% CI 2.03-18.0, p < 0.001). Median progression free survival and overall survival were similar in patients who developed ICIP compared with those who did not, however, patients who presented grade ≥ 2 ICIP had an increased risk of mortality (HR 2.54, 95% CI 1.20-5.34, p = 0.014). CONCLUSION: In this real-world cohort of NSCLC patients treated with ICI, the history of prior radiotherapy was associated with increased risk for ICIP development. Unlike other irAEs, grade ≥ 2 ICIP is an independent prognostic factor for decreased survival in NSCLC patients.

6.
Salud Publica Mex ; 61(3): 352-358, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31276352

RESUMEN

Lung cancer is a major global public health problem, yet the disease is highly stigmatized, which impairs the opportunities to get optimal treatment for these patients. Globally, as well as locally in Mexico, lung cancer is the main cause of cancer-related deaths. Despite this, it is the only one among the five deadliest cancers in Mexico which is not covered by Popular Health Insurance. Lung cancer treatment is a complex algorithm, which requires fully trained personnel to assess each patient in order to determine standard-of-care therapy based on several factors associated with the molecular profile of the tumor, as well as patient characteristics and their financial capabilities. Coupled to this, in the recent decade, several breakthrough therapies have been launched, shifting the outlook for certain patient subgroups. However, none of these novel therapies are currently available to patients who have public-based health insurance. In this paper, we review the inequities present in the Mexican health system and highlight the importance of addressing these opportunities.


El cáncer de pulmón es un problema de salud pública a nivel global. Sin embargo, la enfermedad conlleva un gran nivel de estigma que disminuye las posibilidades de obtener un tratamiento óptimo para estos pacientes. El cáncer de pulmón es la causa principal de muertes relacionadas con cáncer, tanto en el mundo como localmente en México. A pesar de esto, en la lista de las cinco neoplasias con mayor mortalidad en México, el cáncer de pulmón es la única que no se encuentra cubierta por parte del Seguro Popular. El tratamiento del cáncer de pulmón es un algoritmo complejo, el cual requiere personal altamente calificado para la valoración de cada paciente y la determinación del estándar-de-cuidado, dependiendo de varios factores relacionados tanto con el perfil molecular del tumor como con las características del paciente y sus posibilidades económicas. Aunado a esto, en la década en curso ha surgido una gran cantidad de nuevas posibilidades terapéuticas que cambian el pronóstico de ciertos subgrupos de pacientes. Sin embargo, estas terapias no están disponibles para pacientes que se encuentran asegurados por parte del sistema público de salud en México. En este trabajo se revisaron las inequidades que se presentan en el sistema de salud en México y se recalcó la importancia de actuar sobre estas áreas de oportunidad.


Asunto(s)
Accesibilidad a los Servicios de Salud , Disparidades en Atención de Salud , Neoplasias Pulmonares/terapia , Accesibilidad a los Servicios de Salud/organización & administración , Humanos , México
7.
Salud pública Méx ; 61(3): 352-358, may.-jun. 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1094474

RESUMEN

Abstract: Lung cancer is a major global public health problem, yet the disease is highly stigmatized, which impairs the opportunities to get optimal treatment for these patients. Globally, as well as locally in Mexico, lung cancer is the main cause of cancer-related deaths. Despite this, it is the only one among the five deadliest cancers in Mexico which is not covered by Popular Health Insurance. Lung cancer treatment is a complex algorithm, which requires fully trained personnel to assess each patient in order to determine standard-of-care therapy based on several factors associated with the molecular profile of the tumor, as well as patient characteristics and their financial capabilities. Coupled to this, in the recent decade, several breakthrough therapies have been launched, shifting the outlook for certain patient subgroups. However, none of these novel therapies are currently available to patients who have public-based health insurance. In this paper, we review the inequities present in the Mexican health system and highlight the importance of addressing these opportunities.


Resumen: El cáncer de pulmón es un problema de salud pública a nivel global. Sin embargo, la enfermedad conlleva un gran nivel de estigma que disminuye las posibilidades de obtener un tratamiento óptimo para estos pacientes. El cáncer de pulmón es la causa principal de muertes relacionadas con cáncer, tanto en el mundo como localmente en México. A pesar de esto, en la lista de las cinco neoplasias con mayor mortalidad en México, el cáncer de pulmón es la única que no se encuentra cubierta por parte del Seguro Popular. El tratamiento del cáncer de pulmón es un algoritmo complejo, el cual requiere personal altamente calificado para la valoración de cada paciente y la determinación del estándar-de-cuidado, dependiendo de varios factores relacionados tanto con el perfil molecular del tumor como con las características del paciente y sus posibilidades económicas. Aunado a esto, en la década en curso ha surgido una gran cantidad de nuevas posibilidades terapéuticas que cambian el pronóstico de ciertos subgrupos de pacientes. Sin embargo, estas terapias no están disponibles para pacientes que se encuentran asegurados por parte del sistema público de salud en México. En este trabajo se revisaron las inequidades que se presentan en el sistema de salud en México y se recalcó la importancia de actuar sobre estas áreas de oportunidad.


Asunto(s)
Humanos , Disparidades en Atención de Salud , Accesibilidad a los Servicios de Salud/organización & administración , Neoplasias Pulmonares/terapia , México
8.
Ticks Tick Borne Dis ; 10(5): 981-986, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31109835

RESUMEN

Capybaras (Hydrochoerus hydrochaeris Linnaeus, 1766) (Rodentia: Caviidae) are important hosts of Amblyomma ticks (Acari: Ixodidae), which in turn can transmit rickettsiae to humans and animals. However, there is a scarcity of studies about the tick fauna and rickettsial infection in the Amazon region. The present study evaluated rickettsial infection in capybaras and ticks in different areas of the municipality of Rio Branco, state of Acre, in the Western Brazilian Amazon, where rickettsiosis has never been reported. Blood sera from 43 capybaras from four localities in Rio Branco were tested by indirect immunofluorescence assay using Rickettsia rickettsii antigens. Ticks were collected from capybaras and from vegetation as well. Ticks were taxonomically identified to the species level and some of them were tested by PCR, targeting a fragment of the rickettsial gltA gene. Additionally, ticks were tested for bacteria from the genus Borrelia and family Anaplasmatacae. All capybaras submitted to the serological examination were considered non-reactive to R. rickettsii. A total of 410 ticks were collected directly from the capybaras. Amblyomma dubitatum Neumann, 1899 was the most abundant species (82.4%), followed by Amblyomma naponense (Packard, 1869) (14.3%), Amblyomma humerale Koch, 1844 (0.7%), Amblyomma pacae Aragão, 1911 (0.4%), Amblyomma rotundatum Koch 1844 (0.2%) and Amblyomma sp. (1.7%). From the environment 262 ticks were collected: Rhipicephalus microplus (Canestrini, 1888) (88.9%), Dermacentor nitens Neumann, 1897 (9.9%), Amblyomma varium Koch, 1844 (0.7%) and A. rotundatum (0.3%). With the exception of A. humerale, A. rotundatum and R. microplus, all other species are reported here for the first time in the state. Some of the ticks sampled (N = 317) were tested by molecular methods for infection by Rickettsia spp. Rickettsia bellii was identified infecting A. dubitatum and A. rotundatum, while Rickettsia amblyommatis only was found infecting A. humerale and Rickettsia sp. strain Tapirapé was found in A. naponense. This is the first detection of R. bellii and Rickettsia sp. strain Tapirapé in Acre. No Borrelia or Anaplasmataceae were found in the tested ticks. These results add relevant knowledge about the Rickettsia spp. and the acarological fauna in the region of the Western Amazon, and are essential for the maintenance of vigilance about possible pathogens that occur in the state and determination of the risks that they pose to humans and animals that inhabit the region.


Asunto(s)
Enfermedades de los Roedores/epidemiología , Roedores , Rickettsiosis Exantemáticas/veterinaria , Infestaciones por Garrapatas/veterinaria , Garrapatas/microbiología , Garrapatas/fisiología , Anaplasmataceae/aislamiento & purificación , Animales , Antígenos Bacterianos/análisis , Borrelia/aislamiento & purificación , Brasil/epidemiología , Femenino , Larva/crecimiento & desarrollo , Larva/microbiología , Masculino , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Rickettsia/aislamiento & purificación , Rickettsia rickettsii/aislamiento & purificación , Enfermedades de los Roedores/microbiología , Enfermedades de los Roedores/parasitología , Rickettsiosis Exantemáticas/microbiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Garrapatas/clasificación
9.
Univ. sci ; 22(3): 215-236, Oct.-Dec. 2017. ilus, graf, tab
Artículo en Inglés | LILACS, COLNAL | ID: biblio-904715

RESUMEN

Abstract Hydroxyapatite (HAp) was obtained from tilapia scales by two extraction methods: direct calcination and acid-base treatment. The physicochemical characteristics of the obtained HAps were evaluated by thermogravimetric analysis, X-ray fluorescence, X-ray diffraction, scanning electron microscopy, surface area, infrared spectroscopy, and basicity measurement at 298 K by CO2 -pulse titration. Furthermore, the CO2 capture capacity of the solids at high temperature was also determined. Both methods showed the presence of a HAp phase although significant differences in the properties of the solids were found. The HAp obtained by direct calcination, exhibited a lower crystallinity and a greater surface area and basicity than the HAp obtained by the acid-base treatment. These features were correlated with the solid's CO2 capture capacity. In this work, CO2 capture capacity values for HAp yielded by calcination ranged from 2.5 to 3.2 mg CO2 /g captured at 973 K, and for the acid-base treatment-derived HAp, CO2 capture capacity values between 1.2 to 2.5 mg CO2 /g were recorded. These results reveal the potential of HAps extracted from tilapia scales as solids with high CO2 capture capacity, thermal stability, and capture/release cycles reversibility.


Resumen Se obtuvo hidroxiapatita (HAp) de escamas de tilapia por dos métodos de extracción: calcinación directa y tratamiento ácido-base. Las características fisicoquímicas de las HAps obtenidas fueron evaluadas por análisis termogravimétrico, fluorescencia de rayos X, difracción de rayos X, microscopía electrónica de barrido, área superficial, espectroscopia infrarroja y medición de basicidad a 298 K por titulación por pulso de CO2. Adicionalmente, se determinó la capacidad de captura de CO2 de los sólidos a alta temperatura. Ambos métodos mostraron la presencia de una fase de HAp, aunque se encontraron diferencias significativas en las propiedades de los sólidos. La HAp obtenida por calcinación directa exhibió una menor cristalinidad y una mayor área superficial y basicidad que la HAp obtenida con el tratamiento acido-base. Estas características se correlacionaron con la capacidad de captura de CO2 del sólido. En este trabajo, los valores de captura del CO2 con la HAp producidos por calcinación oscilaron entre 2.5 to 3.2 mg CO2/g capturado a 973 K, y con la HAp derivada del tratamiento ácido-base, se registraron valores de captura entre 1.2 to 2.5 mg CO2/g. Estos resultados revelan el potencial de HAps extraídos de escamas de tilapia como sólidos con una alta capacidad de captura de CO2, estabilidad térmica y reversibilidad de los ciclos de captura/liberación.


Resumo A hidroxiapatita (HAp) foi obtida a partir da escama de tilapia usando dois métodos de extração: calcinação direta e tratamento ácido-base. As características físico-químicas das hidroxiapatitas foram avaliadas por análise termogravimétrica, fluorescência de raios-X, difração de raios-X, microscopia eletrônica de varredura, área superficial, espectroscopia de infravermelho e medição de basicidade a 298 K por titulação de pulso de CO2. Além disso, determinou-se a capacidade de captura de CO2 dos sólidos a alta temperatura. Os dois métodos mostraram a presença da fase HAp, no entanto, diferenças significativas foram encontradas nas propriedades dos sólidos, sendo a HAp obtida por calcinação direta a que apresentou menor cristalinidade, maior área superficial e basicidade, características que foram correlacionadas com a capacidade de captura de CO2. Foram encontrados valores entre 2.5 a 3.2 mg CO2/g capturado a 973 K para a HAp obtida por calcinação e, entre 1.2 a 2.5 mg CO2/g para a HAp obtida por tratamento ácido-base. Isto revelou o potencial de HAp's extraídas da escama de tilapia como sólidos com alta capacidade de captura de CO2, estabilidade térmica e reversibilidade na liberação de CO2.


Asunto(s)
Dióxido de Carbono , Tilapia , Hidroxiapatitas/análisis
10.
Materials (Basel) ; 10(12)2017 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-29182560

RESUMEN

Four natural clays were modified with mixed polyoxocations of Al/Fe for evaluating the effect of the physicochemical properties of the starting materials (chemical composition, abundance of expandable clay phases, cationic exchange capacity and textural properties) on final physicochemical and catalytic properties of Al/Fe-PILCs. The aluminosilicate denoted C2 exhibited the highest potential as starting material in the preparation of Al/Fe-PILC catalysts, mainly due to its starting cationic exchange capacity (192 meq/100 g) and the dioctahedral nature of the smectite phase. These characteristics favored the intercalation of the mixed (Al13-x/Fex)7+ Keggin-type polyoxocations, stabilizing a basal spacing of 17.4 Å and high increase of the BET surface (194 m²/g), mainly represented in microporous content. According to H2-TPR analyses, catalytic performance of the incorporated Fe in the Catalytic Wet Peroxide Oxidation (CWPO) reaction strongly depends on the level of location in mixed Al/Fe pillars. Altogether, such physicochemical characteristics promoted high performance in CWPO catalytic degradation of methyl orange in aqueous medium at very mild reaction temperatures (25.0 ± 1.0 °C) and pressure (76 kPa), achieving TOC removal of 52% and 70% of azo-dye decolourization in only 75 min of reaction under very low concentration of clay catalyst (0.05 g/L).

11.
Int Sch Res Notices ; 2017: 8934285, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28913414

RESUMEN

Costa Rica has a significant number of snakebites per year and bacterial infections are often complications in these animal bites. Hereby, this study aims to identify, characterize, and report the diversity of the bacterial community in the oral and cloacal cavities of venomous and nonvenomous snakes found in wildlife in Costa Rica. The snakes where captured by casual encounter search between August and November of 2014 in the Quebrada González sector, in Braulio Carrillo National Park. A total of 120 swabs, oral and cloacal, were taken from 16 individuals of the Viperidae and Colubridae families. Samples were cultured on four different media at room temperature. Once isolated in pure culture, colonies were identified with the VITEK® 2C platform (bioMérieux). In order to test the identification provided on environmental isolates, molecular analyses were conducted on 27 isolates of different bacterial species. Specific 16S rDNA PCR-mediated amplification for bacterial taxonomy was performed, then sequenced, and compared with sequences of Ribosomal Database Project (RDP). From 90 bacterial isolates, 40 different bacterial species were identified from both oral and cloacal swabs. These results indicate the diversity of opportunistic pathogens present and their potential to generate infections and zoonosis in humans.

12.
Ticks Tick Borne Dis ; 8(1): 90-98, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27769655

RESUMEN

Information about tick fauna and monitoring of pathogen prevalences in ticks (Acari: Ixodidae) in various habitat types can enhance knowledge about the epidemiology of tick-borne pathogens in Brazil. This work shows the results of a study of tick parasitism of wild rodents and marsupials collected in seven localities in the southern part of Brazil, within Atlantic Forest and Cerrado biomes. A total of 61 ticks were collected from small mammals, and after identification to the species level, the ticks were individually tested for the presence of bacteria of the genera Rickettsia, Borrelia, family Anaplasmataceae, and protozoa of the genus Babesia. The following species of ticks were found: Amblyomma ovale Koch, 1844, Amblyomma dubitatum Neumann, 1899, Amblyomma fuscum Neumann, 1907, Ixodes aragaoi Fonseca, 1935, Ixodes fuscipes Koch, 1844, Ixodes loricatus Neumann, 1899, and Ixodes schulzei Aragão and Fonseca, 1951. Among tested ticks, no DNA of Borrelia, Babesia or Anaplasmataceae was detected. Two nymphs of A. ovale were found infected with Rickettsia bellii and four nymphs of I. aragaoi with Rickettsia sp., genetically close to Rickettsia monacensis, Rickettsia tamurae and the endosymbiont Rickettsia spp., previously found in various Ixodidae. In one nymph of A. fuscum, DNA of a novel Hepatozoon sp. was found. Additionally we provide novel tick-host associations.


Asunto(s)
Babesia/aislamiento & purificación , Bacterias/aislamiento & purificación , Ixodidae/microbiología , Marsupiales/parasitología , Roedores/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Babesia/genética , Babesiosis/epidemiología , Babesiosis/parasitología , Bacterias/genética , Brasil/epidemiología , Ixodidae/clasificación , Ninfa/clasificación , Filogenia , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
13.
Sustain Sci ; 11(2): 321-330, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30174732

RESUMEN

The forest-grassland mosaics of southern Brazil have been subject to many land use and policy changes over the decades. Like many grasslands around the world, the Campos grasslands are declining with few conservation efforts underway. In contrast, forests receive much attention and many incentives. It is hypothesized that perception of land cover has the potential to shape ecosystems. Here we conduct a questionnaire to further our understanding of decision-making practices that alter landscapes (Campos grassland, Araucaria forest, agriculture and plantation) and direct land policies in the region. Our analysis reveals that plantations are significantly less desirable than the other landscape types. However, plantation land use has increased by 87 % over the past few decades, as a result of industry and government incentives. The proportions of other landscape types have remained consistent over the past two decades. Restoration of native vegetation is not a priority of landowners and restoration would require a financial incentive.

14.
An Acad Bras Cienc ; 87(4): 2139-49, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26536852

RESUMEN

This study assessed the occurrence and distribution of tropane alkaloids and calystegines in genera of the family Solanaceae to identify patterns of distribution and make evolutionary inferences. A database of tropane alkaloids and calystegines occurrences was constructed from the results of a search of scientific websites and a hand search of periodicals. The terms "Solanaceae", "tropane alkaloids", and "calystegines" were used as index terms for a full-text article search unrestricted by date of publications. The number of occurrence and chemical diversity indices were calculated and cluster analysis and principal components analysis were performed. Overall, 996 occurrences were reported, 879 of tropane alkaloids (88.3%) and 117 of calystegines (11.7%). The calystegines were significantly more relevant than tropane alkaloids for characterization of distinct groups of genera on both analyses performed here. This corroborates the trend toward a chemical dichotomy observed on database analysis and somewhat reinforces the correlation between geographic distribution and occurrence of secondary metabolites, as the presence of calystegines alone (without tropane alkaloids) was only reported in genera that have South America as their center of diversity.


Asunto(s)
Solanaceae/química , Alcaloides Solanáceos/análisis , Tropanos/análisis , Biomarcadores/análisis , Cromatografía de Gases y Espectrometría de Masas , Solanaceae/clasificación
15.
Meat Sci ; 97(1): 115-22, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24553493

RESUMEN

The aim of this study was to evaluate selected quality characteristics of a dry-cured lamb leg with different tumbling treatments after salting. The characteristics were measured at different processing times. Three batches of dry-cured lamb legs (nine legs per batch) were prepared with no-, short- and long-tumbling treatments, and microbial counts, NaCl, aw, proximate composition, pH, free fatty acids, water soluble nitrogen, volatile compounds, texture and colour were evaluated at days 1, 22 and 71 of processing. Furthermore, a descriptive sensory analysis (flavour and texture) was performed in the final product (day 71). Time-related changes were observed for most of the characteristics studied. The effect of tumbling was only observed for the sensory attribute pastiness that was higher in tumbled legs. Methyl-branched butanal was only detected in tumbled legs.


Asunto(s)
Manipulación de Alimentos/métodos , Calidad de los Alimentos , Carne/análisis , Cloruro de Sodio/análisis , Adulto , Animales , Recuento de Colonia Microbiana , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Humanos , Carne/microbiología , Persona de Mediana Edad , Músculo Esquelético/química , Oveja Doméstica , Gusto , Compuestos Orgánicos Volátiles/análisis , Agua/análisis , Adulto Joven
19.
Arch. pediatr. Urug ; 79(1): 7-14, 2008.
Artículo en Español | BVSNACUY | ID: bnu-14447

RESUMEN

Introducción: la aterosclerosis comienza a temprana edad y está comprobada su relación con los factores de riesgo cardiovascular (FR). La obesidad es una epidemia mundial. Conocer sus causas y en especial su relación con los hábitos de vida no saludables es importante tanto para la prevención como para su tratamiento. Objetivos: analizar las características clínicas y epidemiológicas de los pacientes; y evaluar la exposición a los FR en niños derivados al Servicio Salud Vital de Médica Uruguaya; describir su evolución luego de la aplicación de un plan de tratamiento multidisciplinario. Material y método: se incluyeron en el estudio todos los pacientes derivados al Programa de Cardiología Preventiva del Servicio en el período diciembre 2006 a junio 2007. Los criterios de referencia fueron niños mayores de 2 años con factores de riesgo cardiovascular ya establecidos o niños con antecedentes familiares de factores de riesgo cardiovascular. Se completó una ficha de recolección de datos para cada paciente. Se evaluaron: antecedentes familiares de obesidad, hipertensión arterial (HA), dislipemias, diabetes y cardiopatía isquémica en paciente joven, tabaquismo activo y pasivo, peso al nacer, alimentación a pecho directo, diagnóstico nutricional, presión arterial (PA), lípidos en sangre, actividad física, sedentarismo, hábitos y conducta alimentaria. Resultados: ingresaron al estudio 97 pacientes referidos a nuestro Servicio, 50,5% fueron del sexo masculino, con una edad promedio de 10 años. El motivo de referencia principal en casi 90% de los pacientes fue la obesidad. El diagnóstico de obesidad se confirmó en el 78,4%, y en más del 50% de los niños la obesidad fue de grado severo. En el 27% (26 niños) la PA fue mayor al percentil (P) 90 (20 pacientes HA y 6 prehipertensión).


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Obesidad/complicaciones , Enfermedades Cardiovasculares , Factores de Riesgo
20.
Academia Nacional de Ciencias de Buenos Aires. Centro Interdisciplinario de Investigaciones Forenses; 1a. ed; 1999. 55-84 p. 23 cm.(Centro Interdisciplinario de Investigaciones Forenses, 31). (76625).
Monografía en Español | BINACIS | ID: bin-76625
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