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1.
Diagnostics (Basel) ; 12(11)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36428942

RESUMO

We developed and standardized an efficient and cost-effective in-house RT-PCR method to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We evaluated sensitivity, specificity, and other statistical parameters by different RT-qPCR methods including triplex, duplex, and simplex assays adapted from the initial World Health Organization- (WHO) recommended protocol. This protocol included the identification of the E envelope gene (E gene; specific to the Sarvecovirus genus), RdRp gene of the RNA-dependent RNA polymerase (specific for SARS-CoV-2), and RNase P gene as endogenous control. The detection limit of the E and the RdRp genes were 3.8 copies and 33.8 copies per 1 µL of RNA, respectively, in both triplex and duplex reactions. The sensitivity for the RdRp gene in the triplex and duplex RT-qPCR tests were 98.3% and 83.1%, respectively. We showed a decrease in sensitivity for the RdRp gene by 60% when the E gene acquired Ct values > 31 in the diagnostic tests. This is associated with the specific detection limit of each gene and possible interferences in the protocol. Hence, developing efficient and cost-effective methodologies that can be adapted to various health emergency scenarios is important, especially in developing countries or settings where resources are limited.

2.
Bioinformation ; 18(12): 1114-1118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37701515

RESUMO

We report the use of a mobile laboratory set up to extract ancient DNA (aDNA) from 34 human coprolites (fossilized faeces) samples. Our approach enabled the rapid genetic characterization of 5,000 years old archeological samples. It is useful for the on-site screening of museums and freshly excavated samples for DNA. This approach is accessible to other investigators as the mobile laboratory was set up using commercially available instruments.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34798937

RESUMO

Fumes generated in the welding process are composed of micrometric and nanometric particles that form when metal fumes condense. The International Agency for Research on Cancer established that many compounds derived from the welding process are carcinogenic to humans. Still, there are few studies related to the role of genetic polymorphisms. This work aimed to analyze the influence of OGG1 Ser326Cys, XRCC1 Arg280His, XRCC1 Arg194Thr, XRCC1 Arg399Gln, XRCC3 Thr241Met, GSTM1, and GSTT1 gene polymorphisms on DNA damage of 98 subjects occupationally exposed to welding fumes and 100 non exposed individuals. The results showed that individuals exposed to welding fumes with XRCC3 Thr241Thr, XRCC3 Thr241Met, and GSTM1 null genotypes demonstrated a significantly higher micronucleus frequency in lymphocytes. In contrast, individuals with XRCC1 Arg399Gln and XRCC1 Gln399Gln genotypes had significant levels of NPBs. OGG1 326 Ser/Cys, OGG1 326 Cys/Cys, XRCC1 194Arg/Thr, XRCC1 194Thr/Thr, and GSTT1 null genotypes exhibited significantly higher apoptotic values. Also, XRCC1 194Arg/Trp, XRCC1 194Thr/Thr, and GSTM1 null genotype carriers had higher necrotic levels compared to XRCC1 194Arg/Arg and GSTM1 nonnull carriers. Compositional analysis revealed the presence of iron, manganese, silicon as well as particles smaller than 2 µm that adhere to each other and form agglomerates. These results may be associated with a mixture of components, such as nitrogen dioxide, carbon monoxide, and metallic fumes, leading to significant DNA damage and cell death processes. These findings demonstrated the importance of the association between individual susceptibility and DNA damage levels due to occupational exposure to welding fumes; and constitute one of the first studies carried out in exposed workers from Colombia.


Assuntos
Citocinese , Dano ao DNA , Ferreiros , Exposição Ocupacional , Colômbia , DNA Glicosilases/genética , Reparo do DNA , Proteínas de Ligação a DNA/genética , Genótipo , Glutationa Transferase/genética , Humanos , Exposição Ocupacional/efeitos adversos , Polimorfismo Genético , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética
4.
Ecotoxicol Environ Saf ; 212: 111935, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33578128

RESUMO

During the welding activities many compounds are released, several of these cause oxidative stress and inflammation and some are considered carcinogenic, in fact the International Agency for Research on Cancer established that welding fumes are carcinogenic to humans. The aim of the present study was to analyze the cytotoxic and genotoxic potential of exposure to welding fumes and to determine concentrations of metals in blood and urine of occupationally exposed workers. We included 98 welders and 100 non-exposed individuals. Our results show significant increase in the frequency of micronuclei (MN), nucleoplasmic bridges (NPB), nuclear buds (NBUD) and necrotic cells (NECR) in cytokinesis-block micronucleus cytome (CBMN-Cyt) assay, as well as in the telomere length (TL) of the exposed individuals with respect to the non-exposed group. In the analysis of the concentrations of inorganic elements using PIXE method, were found higher concentrations of Cr, Fe and Cu in the urine, and Cr, Fe, Mg, Al, S, and Mn in the blood in the exposed group compared to the non-exposed group. A significant correlation was observed between MN and age and between NPB and years of exposure. Additionally, we found a significant correlation for TL in relation to MN, NPB, age and years of exposure in the exposed group. Interestingly, a significant correlation between MN and the increase in the concentration of Mg, S, Fe and Cu in blood samples of the exposed group, and between MN and Cr, Fe, Ni and Cu in urine. Thus, our findings may be associated with oxidative and inflammatory damage processes generated by the components contained in welding fumes, suggesting a high occupational risk in welding workers.


Assuntos
Poluentes Ocupacionais do Ar/análise , Bioensaio , Testes para Micronúcleos/métodos , Exposição Ocupacional/análise , Telômero , Biomarcadores/análise , Citocinese , Dano ao DNA , Humanos , Linfócitos , Estresse Oxidativo , Soldagem
5.
Front Public Health ; 9: 732284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047468

RESUMO

Introduction: As suicide rates increase with age, it is mandatory to carefully assess old age suicidal behaviors. Our aim was to describe the main socio-demographic and clinical features of a sample of suicide attempters aged 65 years and older, and to assess differences within the sample (men vs. women; patients with vs. without a previous history of suicide attempt; patients with vs. without a previous psychiatric history). Methods: Retrospective study conducted at the Maggiore della Carità University Hospital, Novara, Italy. Results: A higher percentage of female patients in our sample were treated by or referred to mental health services, while a greater percentage of male patients required a prolonged clinical observation in the Emergency Room (ER) or in non-psychiatric wards before psychiatric admission. The percentage of patients without previous psychiatric history taking anxiolytic and sedative medications was 25%. Conclusion: It is likely that different clusters and types of suicide attempters exist. Women in our sample appeared more proactive in asking for help, and more likely to be already treated by or referred to a psychiatric service, suggesting the need to facilitate the access to psychiatric services for the male population aged 65 years and older, or to offer support and care for the non-psychiatric reasons (comorbidities, pain, and loss of autonomy) possibly underlying suicidal behavior in this specific group. The use of medications deserves more attention considering the possible critical diagnostic issues in this age group.


Assuntos
Psiquiatria , Tentativa de Suicídio , Idoso , Feminino , Hospitais Universitários , Humanos , Itália/epidemiologia , Masculino , Estudos Retrospectivos , Tentativa de Suicídio/psicologia
6.
Arch Osteoporos ; 15(1): 161, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044638

RESUMO

This review shows the estimated calcium intake in Spain in recent years. Our results indicate that adolescents and the elderly are at risk of insufficient calcium intake. By using the national and the European recommendations, this work contributes to map and compare population's dietary calcium intake in the European countries. PURPOSE AND METHODS : The present work aims to examine calcium intake in the healthy Spanish population of any age and analyze its adequacy to the calcium Recommended Dietary Intake (RDI) for different groups in Spanish population, as well to the Adequate Intake (AI) or Population Reference Intake (PRI) estimated by European Food Safety Authority (EFSA). Forty-three studies published in the last 5 years were eligible for review. RESULTS AND CONCLUSIONS: The results show that infants and children exceed Spanish and EFSA dietary recommendations, adults meet more that 80% of the RDI and EFSA recommendations, and the estimated average calcium intake in the adolescent and elderly groups does not reach 75% of the recommended intake. Representative national studies with a common methodology to estimate calcium intake are needed.


Assuntos
Cálcio da Dieta , Dieta , Recomendações Nutricionais , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Registros de Dieta , Europa (Continente) , Humanos , Lactente , Pessoa de Meia-Idade , Espanha/epidemiologia , Adulto Jovem
7.
Environ Sci Pollut Res Int ; 27(16): 20516-20526, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32246425

RESUMO

Diesel engine exhaust (DEE) is a complex mixture of toxic gases, halogenated aromatic hydrocarbons, alkyl polycyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons, benzene derivatives, metals and diesel exhaust particles (DEPs) generated from the incomplete combustion of diesel fuel. Many of the compounds in this mixture can cause oxidative damage to DNA and are considered carcinogenic for humans. Further, chronic DEE exposure increases risks of cardiovascular and pulmonary diseases. Despite these pervasive health risks, there is limited and inconsistent information regarding genetic factors conferring susceptibility or resistance to DEE genotoxicity. The present study evaluated the effects of polymorphisms in two base excision repair (BER) genes (OGG1 Ser326Cys and XRCC1 Arg280His), one homologous recombination (HRR) gene (XRCC3 Thr241Met) and two xenobiotic metabolism genes (GSTM1 and GSTT1) on the genotoxicity profiles among 123 mechanics exposed to workplace DEE. Polymorphisms were determined by PCR-RFLP. In comet assay, individuals with the GSTT1 null genotype demonstrated significantly greater % tail DNA in lymphocytes than those with non-null genotype. In contrast, these null individuals exhibited significantly lower frequencies of binucleated (BN) cells and nuclear buds (NBUDs) in buccal cells than non-null individuals. Heterozygous hOGG1 326 individuals (hOGG1 326 Ser/Cys) exhibited higher buccal cell NBUD frequency than hOGG1 326 Ser/Ser individuals. Individuals carrying the XRCC3 241 Met/Met polymorphism also showed significantly higher buccal cell NBUD frequencies than those carrying the XRCC3 241 Thr/Thr polymorphism. We found a high flow of particulate matter with a diameter of < 2.5 µm (PM2.5) in the workplace. The most abundant metals in DEPs were iron, copper, silicon and manganese as detected by transmission electron microscopy-energy-dispersive X-ray spectroscopy (TEM-EDX). Scanning electron microscopy (SEM-EDS) revealed particles with diameters smaller than PM2.5, including nanoparticles forming aggregates and agglomerates. Our results demonstrate the genotoxic effects of DEE and the critical influence of genetic susceptibility conferred by DNA repair and metabolic gene polymorphisms that shed light into the understanding of underlying mechanisms.


Assuntos
Exposição Ocupacional , Emissões de Veículos , Dano ao DNA , Reparo do DNA , Humanos , Mucosa Bucal , Polimorfismo Genético , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
8.
Front Neurol ; 11: 5, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32116996

RESUMO

Background and purpose: SWI MRI, a T2*-dominant MRI sequence with T1 shine-through effect, uses intrinsic structural susceptibility to create enhancement among brain structures. We evaluated whether gadolinium-enhanced SWI (SWI-Gd) improves brain metastasis detection in combination with other MRI sequences. Materials and methods: MRI images of 24 patients (46 studies) were prospectively acquired using a 1.5-T scanner. T1-weighted, unenhanced SWI (SWI-U) and SWI-Gd were evaluated blindly to clinical features by two board-certified radiologists. Results: SWI-Gd revealed more significant metastatic lesions than either T1-Gd or SWI-U (p = 0.0004 for either comparator sequence). Moreover, SWI-Gd revealed more lesions only for those patients with ≤5 lesions on T1-Gd (n = 30 studies from 16 patients; p = 0.046). Performing SWI-Gd added <5 min of scanning time with no further additional risk. Conclusions: Our findings suggest that, when added to T1-Gd and other common sequences, SWI-Gd may improve the diagnostic yield of brain metastases with only a few extra minutes of scanning time and no further risk than that of a regular gadolinium-enhanced MRI.

9.
Cells ; 8(8)2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426340

RESUMO

Attention Deficit Hyperactivity Disorder (ADHD) is a highly heritable and prevalent neurodevelopmental disorder that frequently persists into adulthood. Strong evidence from genetic studies indicates that single nucleotide polymorphisms (SNPs) harboured in the ADGRL3 (LPHN3), SNAP25, FGF1, DRD4, and SLC6A2 genes are associated with ADHD. We genotyped 26 SNPs harboured in genes previously reported to be associated with ADHD and evaluated their potential association in 386 individuals belonging to 113 nuclear families from a Caribbean community in Barranquilla, Colombia, using family-based association tests. SNPs rs362990-SNAP25 (T allele; p = 2.46 × 10-4), rs2282794-FGF1 (A allele; p = 1.33 × 10-2), rs2122642-ADGRL3 (C allele, p = 3.5 × 10-2), and ADGRL3 haplotype CCC (markers rs1565902-rs10001410-rs2122642, OR = 1.74, Ppermuted = 0.021) were significantly associated with ADHD. Our results confirm the susceptibility to ADHD conferred by SNAP25, FGF1, and ADGRL3 variants in a community with a significant African American component, and provide evidence supporting the existence of specific patterns of genetic stratification underpinning the susceptibility to ADHD. Knowledge of population genetics is crucial to define risk and predict susceptibility to disease.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Haplótipos/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Negro ou Afro-Americano/genética , Estudos de Casos e Controles , Criança , Colômbia , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Predisposição Genética para Doença , Humanos , Masculino , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Proteína 25 Associada a Sinaptossoma/genética
10.
Rev. chil. cardiol ; 38(2): 107-112, ago. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1042603

RESUMO

RESUMEN ANTECEDENTES: La obesidad es una epidemia mundial que provoca una alta frecuencia de factores de riesgo cardiovascular (FRCV). Se ha observado que la aculturación está incidiendo en los pueblos originarios, como consecuencia de una dieta occidentalizada, lo cual predispone la obesidad, desarrollo de enfermedades cardiovasculares (ECV) y diabetes. En general la población aymara adulta presenta un bajo riesgo cardiovascular innato, lo cual lleva a una baja incidencia de ECV. Objetivos: Conocer la influencia de la occidentalización de la nutrición y evaluar riesgo cardiovascular de la población adolescente aymara de la comuna de Camiña. Método: Estudio descriptivo de corte transversal, en población aymara entre 11 y 18 años de la comuna de Camiña. Muestra probabilística aleatoria simple constituida por 94 individuos. Se aplica una encuesta alimentaria de tendencia de consumo cuantificada, medición antropométrica y exámenes de glicemia y perfil lipídico. Resultados: Se evaluaron 94 participantes 57,4 % mujeres. Malnutrición por exceso presenta 41%; riesgo cardiovascular según medición de perímetro de cintura (PC) 55,2%; colesterol total alterado 52,6% y triglicéridos alterados 89,5%. Mediante encuesta alimentaria se pudo conocer que 71,7% mantenían una dieta hipercalórica, 69,8 % una dieta hiperglucídica, 45% una dieta hiperlipídica. Conclusión: En la población adolescente aymara estudiada se encontraron factores de riesgo cardiovascular alterados, como malnutrición por exceso, PC aumentado, Colesterol total y Triglicéridos elevados. Su alimentación era "de tipo occidental", consumiendo alimentos procesados y elaborados con dietas hipercalóricas, hiperglucídicas e hiperlipídicas.


ABSTRACT BACKGROUND. Obesity is widely known to lead to increased cardiovascular risk factors (RF). Cultural changes observed in native populations, including the adoption of a western type nutrition, leads to obesity, increased levels of RF ,cardiovascular diseases and diabetes. Aim: To determine the influence of a western type nutrition on RF among adolescent Aymaras in northern Chile. Methods: A cross sectional descriptive study was performed in Camiña (northern Chile), including Aymaras aged 11 to 18 years-old. A quantified alimentary consumption questionnaire, anthropometric measurements, blood glucose levels and lipid profile were obtained. Results: 94 subjects (57% women) were studied. Excess malnutrition (obesity) was present in 41%, abnormally high waist circumference in 55%, high cholesterol levels in 53%, and high triglycerides in 90% of subjects. The contents of the diet being consumed was high in calories in 72%, high in sugar in 70% and high in lipids in 45%. Conclusion: A high prevalence of cardiovascular RF was present in adolescent Aymaras of northern Chile. This finding was related to the consumption of a western type diet, rich in calories, lipids and sugar, leading to obesity


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Etnicidade , Hipernutrição/epidemiologia , Fatores de Risco de Doenças Cardíacas , Obesidade , Índios Sul-Americanos , Índice de Massa Corporal , Chile/epidemiologia , Antropometria , Prevalência , Estudos Transversais , Inquéritos e Questionários , Dieta
11.
Ecotoxicol Environ Saf ; 171: 264-273, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30612014

RESUMO

Diesel engine exhaust (DEE), which is the product of diesel combustion, is considered carcinogenic in humans. It comprises toxic gases, polycyclic aromatic hydrocarbons (PAHs) and particulate matter which can reach the pulmonary parenchyma and trigger various diseases, including cancer. The aim of the present study was to evaluate the potential cytotoxic and genotoxic effects of DEE exposure on peripheral blood and buccal epithelial cells in mechanics occupationally exposed to DEE. We recruited 120 exposed mechanics and 100 non-exposed control individuals. Significant differences were observed between the two groups in terms of percentage of tail DNA and damage index (DI) in the alkaline comet assay; levels of biomarkers by cytokinesis-block micronucleus cytome (CBMN-Cyt) assay; frequency of micronucleus (MN), nucleoplasmic bridge (NPB), nuclear bud (NBUD) and apoptotic cells (APOP) and levels of biomarkers for micronucleus, karyorrhexis (KRX), karyolysis (KRL) and condensed chromatin (CC) by the buccal micronucleus cytome (BM-Cyt) assay. A significant and positive correlation was found between the frequency of MN in lymphocytes and buccal cells in the exposed group. Also, there was a significant correlation between age and percentage of tail DNA and DI in the comet assay, APOP and MN in the CBMN-Cyt assay and NBUD and MN in the BM-Cyt assay. Additionally, we found a positive and significant correlation of MN frequency in lymphocytes and buccal cells and age and MN frequency in lymphocytes with the time of service (years). Regarding lifestyle-related factors, a significant correlation was observed between meat and vitamin consumption and NBUD formation on CBMN-Cyt and between meat consumption and MN formation on CBMN-Cyt. Of the BM-Cyt biomarkers, there was a correlation between alcohol consumption and NBUD formation and between binucleated cell (BN), pyknosis (PYC), CC and KRL occurrence and family cancer history. These results are the first data in Colombia on the cytotoxic and genotoxic effects induced by continuous exposure to DEE and thus showed the usefulness of biomarkers of the comet, CBMN-Cyt and BM-Cyt assays for human biomonitoring and evaluation of cancer risk in the exposed populations.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Apoptose/efeitos dos fármacos , Dano ao DNA , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Emissões de Veículos/toxicidade , Células Cultivadas , Colômbia , Ensaio Cometa , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Testes para Micronúcleos/métodos , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/metabolismo , Exposição Ocupacional/análise
12.
Water Sci Technol ; 72(7): 1226-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26398039

RESUMO

This study offers the opportunity to utilize Undaria pinnatifida and Phragmites australis to remove lead from water in permeable reactive barrier (PRB) technology. Its efficacy was tested using batch experiments and PRB column systems. From the batch experiment results, a higher adsorption capacity was observed for Undaria pinnatifida. Nevertheless, Phragmites australis in the column system efficiently removed lead and the breakthrough occurred at the same time for both biomaterials. To dissipate this difference, a sequential extraction for metal speciation analysis was used for both columns. The results have shown that each biomaterial has a dominant mechanism. Phragmites australis removed lead by physical adsorption, whereas Undaria pinnatifida showed a higher tendency to bind lead due to organic matter, primary and secondary minerals.


Assuntos
Chumbo/isolamento & purificação , Poaceae/química , Undaria/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Biomassa , Modelos Teóricos , Poaceae/crescimento & desenvolvimento , Propriedades de Superfície , Undaria/crescimento & desenvolvimento
13.
Water Sci Technol ; 70(2): 307-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25051478

RESUMO

As alternative materials for heavy metal removal, this study investigated biosorbents to determine their suitability for permeable reactive barriers. The lead removal efficiencies of brown seaweed (Undaria pinnatifida) and reed (Phragmites australis) were determined under different conditions (batch and column system). The experimental results for these biomaterials fitted the Langmuir isotherm with high correlation values. It was verified that the influence of temperature on affinity was higher than that on adsorption capacity. While the lead removal efficiency of U. pinnatifida was higher than of P. australis in the batch experiments, lead removal efficiency decreased for both materials at approximately the same time in the column experiments. This indicates that the dominance of the chemical and physical adsorption mechanisms could result in differences in these systems.


Assuntos
Chumbo/química , Poaceae , Alga Marinha , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Reatores Biológicos
14.
Rev Biol Trop ; 61(3): 1229-41, 2013 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-24027920

RESUMO

Sponges have an important ecological role in coral reef ecosystems. However, when compared to other benthic Phyla, it has been little researched. This research was focused in the variability of the community structure of sponges in three locations at Morrocoy National Park (Cayo Sombrero, Playa Mero and Punta Brava) exposed to different environmental conditions (transparency and currents intensity) and affected in different degree of severity by a mass mortality event in 1996. A total of 15 transects (10 m long and 1 m wide) were evaluated in three strata (between 3 and 15 m depth) in each site, where all the individuals were counted by species. Relative abundance by species, diversity and evenness were calculated. Locations showed differences respect turbidity, wave and current intensity. 27 species were found in Morrocoy; Cayo Sombrero (23), Playa Mero (18) and Punta Brava (15). Agelas sceptrum, Amphimedon erina and Niphates erecta were the most common in first location; Niphates erecta and Dysidea etheria in Playa Mero and Dysidea etheria, Niphates erecta and Amphimedon erina in Punta Brava. The species composition showed statistical differences between all three locations; Cayo Sombrero resulted the most diverse and even, followed by Playa Mero and Punta Brava. According to Sorensen Similarity Index results, Cayo Sombrero and Playa Mero were more similar, while Punta Brava resulted the most different. The variability in environmental conditions and the differential mass mortality effects of 1996 in all three reefs, were probably the main causes of the differences between their sponge communities. Nevertheless, we cannot conclude about the weight of these factors.


Assuntos
Recifes de Corais , Meio Ambiente , Poríferos/classificação , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental , Densidade Demográfica , Água do Mar , Venezuela
15.
Rev. biol. trop ; 61(3): 1229-1241, sep. 2013. ilus, graf, mapas, tab
Artigo em Espanhol | LILACS | ID: lil-688472

RESUMO

Sponges have an important ecological role in coral reef ecosystems. However, when compared to other benthic Phyla, it has been little researched. This research was focused in the variability of the community structure of sponges in three locations at Morrocoy National Park (Cayo Sombrero, Playa Mero and Punta Brava) exposed to different environmental conditions (transparency and currents intensity) and affected in different degree of severity by a mass mortality event in 1996. A total of 15 transects (10m long and 1m wide) were evaluated in three strata (between 3 and 15m depth) in each site, where all the individuals were counted by species. Relative abundance by species, diversity and evenness were calculated. Locations showed differences respect turbidity, wave and current intensity. 27 species were found in Morrocoy; Cayo Sombrero (23), Playa Mero (18) and Punta Brava (15). Agelas sceptrum, Amphimedon erina and Niphates erecta were the most common in first location; Niphates erecta and Dysidea etheria in Playa Mero and Dysidea etheria, Niphates erecta and Amphimedon erina in Punta Brava. The species composition showed statistical differences between all three locations; Cayo Sombrero resulted the most diverse and even, followed by Playa Mero and Punta Brava. According to Sorensen Similarity Index results, Cayo Sombrero and Playa Mero were more similar, while Punta Brava resulted the most different. The variability in environmental conditions and the differential mass mortality effects of 1996 in all three reefs, were probably the main causes of the differences between their sponge communities. Nevertheless, we cannot conclude about the weight of these factors.


El presente estudio pone en evidencia la variación en la estructura de la comunidad de esponjas en tres localidades del Parque Nacional Morrocoy (Cayo Sombrero, Playa Mero y Punta Brava) con distintas condiciones ambientales y afectadas diferencialmente por una mortalidad masiva ocurrida en 1996. En un total de 15 transectos de 10m de largo y 1m de ancho en cuatro estratos comprendidos entre 3 y 15m de profundidad en cada localidad; se contabilizaron los individuos por especie para calcular la abundancia relativa, diversidad y equidad. Se analizaron las variables ambientales por localidad y se aprecian diferencias entre ellas con respecto a la corriente, turbidez, y exposición al oleaje. Fueron totalizadas 27 especies; Cayo Sombrero (23), Playa Mero (18) y Punta Brava (15), en la primera localidad domina: Agelas sceptrum, Amphimedon erina y Niphates erecta, en Playa Mero: Niphates erecta y Dysidea etherea y en Punta Brava: Dysidea etherea, Niphates erecta y Amphimedon erina. La composición de especies mostró diferencias estadísticamente significativas entre localidades. La mayor diversidad y equidad correspondió a Cayo Sombrero; donde las condiciones fueron más favorables para el crecimiento de estos organismos, seguido de Playa Mero y Punta Brava, guardando las dos primeras mayor similitud entre sí, según Índice de Sorensen.


Assuntos
Animais , Recifes de Corais , Meio Ambiente , Poríferos/classificação , Conservação dos Recursos Naturais , Monitoramento Ambiental , Densidade Demográfica , Água do Mar , Venezuela
16.
PLoS One ; 7(2): e30506, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363443

RESUMO

Biodiversity conservation and ecosystem-service provision will increasingly depend on the existence of secondary vegetation. Our success in achieving these goals will be determined by our ability to accurately estimate the structure and diversity of such communities at broad geographic scales. We examined whether the texture (the spatial variation of the image elements) of very high-resolution satellite imagery can be used for this purpose. In 14 fallows of different ages and one mature forest stand in a seasonally dry tropical forest landscape, we estimated basal area, canopy cover, stem density, species richness, Shannon index, Simpson index, and canopy height. The first six attributes were also estimated for a subset comprising the tallest plants. We calculated 40 texture variables based on the red and the near infrared bands, and EVI and NDVI, and selected the best-fit linear models describing each vegetation attribute based on them. Basal area (R(2) = 0.93), vegetation height and cover (0.89), species richness (0.87), and stand age (0.85) were the best-described attributes by two-variable models. Cross validation showed that these models had a high predictive power, and most estimated vegetation attributes were highly accurate. The success of this simple method (a single image was used and the models were linear and included very few variables) rests on the principle that image texture reflects the internal heterogeneity of successional vegetation at the proper scale. The vegetation attributes best predicted by texture are relevant in the face of two of the gravest threats to biosphere integrity: climate change and biodiversity loss. By providing reliable basal area and fallow-age estimates, image-texture analysis allows for the assessment of carbon sequestration and diversity loss rates. New and exciting research avenues open by simplifying the analysis of the extent and complexity of successional vegetation through the spatial variation of its spectral information.


Assuntos
Dessecação , Processamento de Imagem Assistida por Computador , Comunicações Via Satélite , Árvores/fisiologia , Clima Tropical , Biodiversidade , Modelos Lineares , México , Modelos Biológicos , Estatísticas não Paramétricas
17.
Nephrology (Carlton) ; 17(1): 26-31, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22022934

RESUMO

AIM: To evaluate the compassionate use of cinacalcet for the management of secondary hyperparathyroidism in patients who are not on dialysis. METHODS: Patients with stage 4-5 chronic kidney disease (CKD) who were not on dialysis, had an intact parathyroid hormone (iPTH) level greater than 300 pg/mL, and had not responded satisfactorily to treatment with phosphate binders and vitamin D were prospectively studied. Patients received 6 months of compassionate treatment with cinacalcet, which was initiated at a dose of 30 mg/day orally and flexibly dosed thereafter based on iPTH levels. RESULTS: Twenty-six patients with a mean age±standard deviation (SD) of 58.8±16.1 years were enrolled in the study and included in the statistical analysis. The mean percentage change in iPTH levels from baseline after 6 months of treatment was -67.9±17.0%, with 92.3% (95% confidence interval (CI), 75.9-97.9) of patients showing an iPTH level within the limits recommended by Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. The mean serum calcium concentrations had decreased significantly at the end of the study (-8.0±6.9%), while the mean serum phosphorus concentration had significantly increased (+8.3±17.0%). CONCLUSION: Our results suggest that cinacalcet may be a useful alternative for the treatment of secondary hyperparathyroidism in pre-dialysis patients who are unresponsive to other treatments. The hypocalcemia and hyperphosphatemia reported in previous studies may not occur if a moderate dose of calcimimetics is used in patients with marginal glomerular filtration rates, especially if combined with vitamin D analogues and calcium-based phosphate binders.


Assuntos
Calcimiméticos , Cálcio , Hiperparatireoidismo Secundário/tratamento farmacológico , Nefropatias/complicações , Naftalenos , Hormônio Paratireóideo/sangue , Vitamina D , Adulto , Idoso , Calcimiméticos/administração & dosagem , Calcimiméticos/efeitos adversos , Cálcio/sangue , Cálcio/uso terapêutico , Doença Crônica , Cinacalcete , Ensaios de Uso Compassivo , Quimioterapia Combinada , Feminino , Humanos , Hiperparatireoidismo Secundário/etiologia , Hiperparatireoidismo Secundário/metabolismo , Hiperparatireoidismo Secundário/fisiopatologia , Nefropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Naftalenos/administração & dosagem , Naftalenos/efeitos adversos , Fósforo/sangue , Índice de Gravidade de Doença , Resultado do Tratamento , Vitamina D/sangue , Vitamina D/uso terapêutico
18.
Chem Biodivers ; 7(2): 302-26, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20151378

RESUMO

Erythroxylum, the most representative genus of the Erythroxylaceae family, presents tropane alkaloids as main constituents. This class of compounds greatly contributes to the chemotaxonomic characterization of plants of this genus, and it has important medical uses and shows toxic effects. This review describes 186 tropane alkaloids in the 35 species of Erythroxylum distributed worldwide. In addition, a compilation of their (13)C-NMR spectral data is presented.


Assuntos
Erythroxylaceae/química , Tropanos/química , Isótopos de Carbono , Espectroscopia de Ressonância Magnética , Tropanos/isolamento & purificação
19.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 7139-42, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281922

RESUMO

New wireless technologies make possible the implementation of high level integration wireless devices which allow the replacement of traditional large wired monitoring devices. This kind of devices favours at-home hospitalization, reducing the affluence to sanitary assistance centers to make routine controls. This fact causes a really favourable social impact, especially for elder people, rural-zone inhabitant, chronic patients and handicapped people. Furthermore, it offers new functionalities to physicians and will reduce the sanitary cost. Among these functionalities, biomedical signals can be sent to other devices (screen, PDA, PC...) or processing centers, without restricting the patients' mobility. The aim of this project is the development and implementation of a reduced size multi-channel electrocardiograph based on IEEE 802.11, which allows wireless monitoring of patients, and the insertion of the information into the TCP/IP Hospital network.

20.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 2433-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282729

RESUMO

Most of the patients who are in hospitals and, increasingly, patients controlled remotely from their homes, at-home monitoring, are continuously monitored in order to control their evolution. The medical devices used up to now, force the sanitary staff to go to the patients' room to control the biosignals that are being monitored, although in many cases, patients are in perfect conditions. If patient is at home, it is he or she who has to go to the hospital to take the record of the monitored signal. New wireless technologies, such as BlueTooth and WLAN, make possible the deployment of systems that allow the display and storage of those signals in any place where the hospital intranet is accessible. In that way, unnecessary displacements are avoided. This paper presents a network architecture that allows the identification of the biosignal acquisition device as IP network nodes. The system is based on a TCP/IP architecture which is scalable and avoids the deployment of a specific purpose network.

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