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1.
Food Chem X ; 22: 101486, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38840720

RESUMO

The study investigated the behavior of seventeen amino acids during spontaneous (SF) and starter culture (SC) fermentation of Criollo cocoa beans from Copallín, Guadalupe and Tolopampa, Amazonas-Peru. For this purpose, liquid chromatography (UHPLC) was used to quantify amino acids. Multivariate analysis was used to differentiate the phases of the fermentation process. The percentage of essential amino acids during SC fermentation (63.4%) was higher than SF (61.8%); it was observed that the starter culture accelerated their presence and increased their concentration during the fermentation process. The multivariate analysis identified a first stage (day 0 to day 2), characterized by a low content of amino acids that increased due to protein hydrolysis. The study showed that adding the starter culture (Saccharomyces cerevisiae) to the fermentation mass increased the concentration of essential amino acids (63.0%) compared to the spontaneous process (61.8%). Moreover, this addition reduced the fermentation time (3-4 days less), demonstrating that the fermentation process with a starter culture allows obtaining a better profile of amino acids precursors of flavor and aroma.

2.
Zoology (Jena) ; 156: 126058, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459729

RESUMO

Characterizing the factors that shape variation in brain size in natural populations is crucial to understanding the evolution of brain size in animals. Here, we explore how relative brain size and brain allometry vary with drainage, predation risk and sex in natural populations of the electric knifefish Brachyhypopomus occidentalis. Fish were sampled from high and low predation risk sites within two independent river drainages in eastern and central Panamá. Overall, we observed low variation in brain-body size allometric slopes associated with drainage, predation risk and sex category. However, we observed significant differences in allometric intercepts between predation risk sites. We also found significant differences in relative brain mass associated with drainage, as well as significant differences in absolute brain mass associated with drainage, predation risk and sex category. Our results suggest potential constraints in brain-body allometry across populations of B. occidentalis. However, both drainage and predation risk may be playing a role in brain mass variation among populations. We suggest that variation in brain mass in electric fishes is affected by multiple extrinsic and intrinsic factors, including geography, environmental complexity, social interaction and developmental or functional constraints.


Assuntos
Peixe Elétrico , Animais , Evolução Biológica , Tamanho do Órgão , Encéfalo , Comportamento Predatório
3.
Ecol Evol ; 12(8): e9159, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35919393

RESUMO

The Andean plant endemic Puya is a striking example of recent and rapid diversification from central Chile to the northern Andes, tracking mountain uplift. This study generated 12 complete plastomes representing nine Puya species and compared them to five published plastomes for their features, genomic evolution, and phylogeny. The total size of the Puya plastomes ranged from 159,542 to 159,839 bp with 37.3%-37.4% GC content. The Puya plastomes were highly conserved in organization and structure with a typical quadripartite genome structure. Each of the 17 consensus plastomes harbored 133 genes, including 87 protein-coding genes, 38 tRNA (transfer RNA) genes, and eight rRNA (ribosomal RNA) genes; we found 69-78 tandem repeats, 45-60 SSRs (simple sequence repeats), and 8-22 repeat structures among 13 species. Four protein-coding genes were identified under positive site-specific selection in Puya. The complete plastomes and hypervariable regions collectively provided pronounced species discrimination in Puya and a practical tool for future phylogenetic studies. The reconstructed phylogeny and estimated divergence time for the lineage suggest that the diversification of Puya is related to Andean orogeny and Pleistocene climatic oscillations. This study provides plastome resources for species delimitation and novel phylogenetic and biogeographic studies.

4.
ESMO Open ; 7(5): 100560, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988454

RESUMO

BACKGROUND: Lung cancer is the second most common cancer and leading cause of cancer mortality worldwide. Recent advances in molecular testing and targeted therapy have improved survival among patients with metastatic non-small-cell lung cancer (NSCLC). We sought to quantify and describe molecular testing among metastatic non-squamous NSCLC cases in selected Southeast Asian countries and describe first-line therapy chosen. PATIENTS AND METHODS: A retrospective study was conducted based on incident lung cancer cases diagnosed between 2017 and 2019 in Lampang (Thailand), Penang (Malaysia), Singapore and Yogyakarta (Indonesia). Cases (n = 3413) were defined using the International Classification of Diseases for Oncology third edition. In Singapore, a clinical series obtained from the National Cancer Centre was used to identify patients, while corresponding population-based cancer registries were used elsewhere. Tumor and clinical information were abstracted by chart review according to a predefined study protocol. Molecular testing of epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) gene rearrangement, ROS1 gene rearrangement and BRAF V600 mutation was recorded. RESULTS: Among 2962 cases with a specified pathological diagnosis (86.8%), most patients had non-squamous NSCLC (75.8%). For cases with staging information (92.1%), the majority presented with metastatic disease (71.3%). Overall, molecular testing rates in the 1528 patients with stage IV non-squamous NSCLC were 67.0% for EGFR, 42.3% for ALK, 39.1% for ROS1, 7.8% for BRAF and 36.1% for PD-L1. Among these patients, first-line systemic treatment included chemotherapy (25.9%), targeted therapy (35.6%) and immunotherapy (5.9%), with 31% of patients having no record of antitumor treatment. Molecular testing and the proportion of patients receiving treatment were highly heterogenous between the regions. CONCLUSIONS: This first analysis of data from a clinically annotated registry for lung cancer from four settings in Southeast Asia has demonstrated the feasibility of integrating clinical data within population-based cancer registries. Our study results identify areas where further development could improve patient access to optimal treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1 , Quinase do Linfoma Anaplásico/genética , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/uso terapêutico , Tailândia , Receptores ErbB/genética
5.
Environ Sci Pollut Res Int ; 29(52): 79466-79477, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35710972

RESUMO

The glass particles were coated with Spirulina sp. LEB-18 and bioblends of Spirulina sp. LEB-18/chitosan by casting technique and, afterward, it was verified its potential as adsorbents for basic and acid dyes. Nine Spirulina sp. suspensions with different components were used to coat the glass particles, and in the best condition of coating were prepared the bioblends with chitosan. The coated glass particles with Spirulina sp. and its bioblends with chitosan were applied in adsorption of the allura red (acid) and methylene blue (basic) dyes in a batch operation evaluate the pH effect, and a fixed bed column operation, being evaluated to the removal percentage and adsorption capacity of the column. The glass particles coated with Spirulina sp. applied in batch adsorption showed the highest removal percentages for allura red dye (35 to 45%) at pH 4.0, and for methylene blue dye (35 to 80%) at pH 6.0 and 8.0. In fixed bed column using glass particles coated with bioblends were reached the amount dye of 54.2 mg of adsorbed allura red dye and 60.2 mg of the of adsorbed methylene blue dye, respectively. Moreover, it was found good dye adsorption capacities, around 89 mg g-1, for both dyes, in acidic and basic pH values. Based on these results, these bioblends coated glass particles can be applied as an adsorbent for different types of dyes in adsorption column.


Assuntos
Quitosana , Spirulina , Poluentes Químicos da Água , Purificação da Água , Adsorção , Corantes/química , Quitosana/química , Purificação da Água/métodos , Azul de Metileno/química , Suspensões , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
6.
Rev. peru. biol. (Impr.) ; 29(2): e22557, abr.-jun. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1409958

RESUMO

Resumen Puya raimondii es una especie endémica de los altos Andes de Perú y Bolivia. En el Perú se distribuye desde 8.068501°S, 16.170280°W hasta 16.180580° S, 70.658873° W, entre los 3600 y 4800 m de altitud, viviendo en condiciones climáticas extremas propias de la Puna, donde juega un papel ecológico importante. Pese a la amplia distribución de las poblaciones de P. raimondii en el Perú, aparentemente son bastante uniformes morfológicamente; por lo que surgen las siguientes preguntas: ¿Podrán las actuales herramientas moleculares mostrar diferencias entre las numerosas poblaciones? ¿Son suficientes las áreas de conservación establecidas para P. raimondii ya que albergan la variabilidad existente? Para responder a estas interrogantes, este trabajo tuvo como objetivo evaluar la diversidad genética y estructura genética en una población del norte del país, Pachapaqui (departamento de Ancash), una población del centro, Yanacancha (Junín), y una población del sur, Lampa - sector Choconchaca (Puno), utilizando marcadores microsatélites (SSR) específicos para la especie. Los parámetros de diversidad genética utilizados incluyeron número de alelos (A), alelos exclusivos (RA), heterocigosidad observada (Ho), heterocigosidad esperada (He) e índice de contenido polimórfico (PIC). Los resultados mostraron que el número total de A varió de 2 ‒ 13, los valores de He fueron 0 ‒ 0.723 y Ho 0 ‒ 0.929, con un He promedio de 0.217, indicando una diversidad genética moderada a alta, siendo la población de Lampa-sector Choconchaca, la que presentó mayor diversidad alélica y mayor diversidad genética. La prueba de Hardy-Weinberg mostró que las poblaciones se encuentran en desequilibrio HW, el análisis estadístico indica un 65% de variación genética a nivel poblacional y valores de FST (0.426) y RST (0.650) que indican alta diferenciación genética entre poblaciones, con dos grupos genéticos (K=2) que corresponden a las poblaciones del centro-norte y sur del Perú. Los resultados brindan información útil para establecer estrategias de conservación para P. raimondii, que conduzcan a la creación de una área de conservación adicional para proteger a las poblaciones del sur del Perú.


Abstract Puya raimondii is an endemic species from the high Andes of Peru and Bolivia. In Peru it is distributed from 8.068501°S, 16.170280°W to 16.180580°S, 70.658873°W, between 3600 and 4800 m, living in extreme climatic conditions typical of the Puna, where it plays an important ecological role. Despite the wide distribution of P. raimondii populations in Peru, they appear to be fairly uniform morphologically. The following questions arise: Will the current molecular tools be able to show differences between the numerous populations? Are the conservation areas established for P. raimondii sufficient since they harbor the existing variability? To answer these questions, this work aimed to evaluate the genetic diversity and genetic structure in a northern population, Pachapaqui (Ancash department), a central population, Yanacancha (Junin), and a southern population, Lampa - Choconchaca sector (Puno), using microsatellite markers (SSR) specific for the species. The genetic diversity parameters used included number of alleles (A), exclusive alleles (RA), observed heterozygosity (Ho), expected heterozygosity (He), and polymorphic content index (PIC). The results showed that the total number of A varied from 2 - 13, the He values were 0 ‒ 0.723 and Ho 0 ‒ 0.929, with an average He of 0.217, indicating a moderate to high genetic diversity, being the population of Lampa-Choconchaca sector, the one that presented the greatest allelic diversity and the greatest genetic diversity. The Hardy-Weinberg test showed that the populations are in HW disequilibrium, the statistical analysis indicates 65% of the genetic variation at the population level and values of FST (0.426) and RST (0.650) that indicate high genetic differentiation among populations, with two genetic groups (K=2) that correspond to the populations of northern-central and southern Peru. The results provide useful information to establish conservation strategies for P. raimondii, which lead to the creation of an additional conservation area to protect the populations in southern Peru.

7.
Immunotherapy ; 14(7): 521-530, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35306855

RESUMO

Background: Lung injury and STAT1 deficit induce EGFR overexpression in SARS-CoV-2 infection. Patients & methods: A phase I/II trial was done to evaluate the safety and preliminary effect of nimotuzumab, an anti-EGFR antibody, in COVID-19 patients. Patients received from one to three infusions together with other drugs included in the national guideline. Results: 41 patients (31 severe and 10 moderate) received nimotuzumab. The median age was 62 years and the main comorbidities were hypertension, diabetes and cardiovascular disease. The antibody was very safe and the 14-day recovery rate was 82.9%. Inflammatory markers decreased over time. Patients did not show signs of fibrosis. Conclusion: Nimotuzumab is a safe antibody that might reduce inflammation and prevent fibrosis in severe and moderate COVID-19 patients. Clinical Trial Registration: RPCEC00000369 (rpcec.sld.cu).


Background: After SARS-CoV-2 infection, many cells in the lung express a new receptor called EGFR. Overexpression of EGFR can worsen the pulmonary disease and provoke fibrosis. Patients & methods: The initial impact of using a drug that blocks EGFR, nimotuzumab, was evaluated in COVID-19 patients. Results: 41 patients received nimotuzumab by the intravenous route together with other medications. The median age was 62 years, and patients had many chronic conditions including hypertension, diabetes and cardiac problems. Treatment was well tolerated and 82.9% of the patients were discharged by day 14. Serial laboratory tests, x-rays and CT scan evaluations showed the improvement of the patients. Conclusion: Nimotuzumab is a safe drug that can be useful to treat COVID-19 patients.


Assuntos
Anticorpos Monoclonais Humanizados , Tratamento Farmacológico da COVID-19 , Anticorpos Monoclonais Humanizados/efeitos adversos , Receptores ErbB , Fibrose , Humanos , Pessoa de Meia-Idade , SARS-CoV-2
8.
Genomics ; 113(4): 2537-2546, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34089785

RESUMO

Puya raimondii, the Queen of the Andes, is an endangered high Andean species in the Bromeliaceae family. Here, we report its first genome to promote its conservation and evolutionary study. Comparative genomics showed P. raimondii diverged from Ananas comosus about 14.8 million years ago, and the long terminal repeats were likely to contribute to the genus diversification in last 3.5 million years. The gene families related to plant reproductive development and stress responses significantly expanded in the genome. At the same time, gene families involved in disease defense, photosynthesis and carbohydrate metabolism significantly contracted, which may be an evolutionary strategy to adapt to the harsh conditions in high Andes. The demographic history analysis revealed the P. raimondii population size sharply declined in the Pleistocene and then increased in the Holocene. We also designed and tested 46 pairs of universal primers for amplifying orthologous single-copy nuclear genes in Puya species.


Assuntos
Bromeliaceae , Bromeliaceae/genética , Genes de Plantas , Genoma de Planta , Genômica , Filogenia
9.
Environ Sci Pollut Res Int ; 26(28): 28510-28523, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30929177

RESUMO

In this work, three polymer suspensions were used for coating glass beads (GB), porcelain beads (PB), and polyethylene pellets (PP) in spouted bed. Subsequently, the continuous adsorption assays of the food dye Brilliant Blue FCF in a fixed bed column were performed, which was packed with the covered particles. Also, the static adsorption assays were carried out. The adsorption equilibrium isotherms were fitted by Freundlich, Langmuir, and Temkin models, being that the Temkin model was the most suitable to represent the equilibrium data. The particle coating in the spouted bed showed promising results due to the high efficiency of the process. The PB, GB, and PP obtained coating efficiency values in the range to 92-96% when using the suspension of chitosan and hydroxyethyl cellulose. However, only the polyethylene particles coated with the chitosan suspension maintained its coating efficiency (95%). The maximum adsorption capacities at equilibrium of the coated particles of PP and GB were achieved with the chitosan suspension, being the values of around 800 mg g-1. Thus, the chitosan-coated polyethylene particles showed to be a promising adsorbent for fixed bed column. Graphical abstract.


Assuntos
Quitosana/metabolismo , Corantes/química , Polímeros/química , Adsorção , Quitosana/química , Cinética
10.
Appl Plant Sci ; 7(12): e11308, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31890354

RESUMO

PREMISE: Microsatellite primers were developed for Puya raimondii (Bromeliaceae), an endangered species distributed in the Andean Mountains of Bolivia and Peru. METHODS AND RESULTS: Genome skimming of P. raimondii, P. macrura, and P. hutchisonii resulted in the selection of 46 pairs of cross-species microsatellite markers. Of these, 12 microsatellite primer pairs produced clear and polymorphic bands in P. raimondii. These primer sets were then used for the detection of potential polymorphisms in 84 P. raimondii individuals collected from four populations in Peru. The number of alleles per locus ranged from one to six, and the observed and expected levels of heterozygosity ranged from 0.000 to 0.8929 and from 0.000 to 0.7662, respectively. CONCLUSIONS: The microsatellite markers developed in this study will be useful for future population genetic analyses and breeding system studies in P. raimondii.

11.
Health Promot Chronic Dis Prev Can ; 35 Suppl 1: 2-186, 2015.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-26011811

RESUMO

PURPOSE AND INTENDED AUDIENCE: Each year, the Canadian Cancer Statistics publication provides an estimate of expected case counts and rates for common cancer sites for the current year in Canada as a whole and in the provinces and territories. This monograph expands on the Canadian Cancer Statistics publication by providing historical and projected cancer incidence frequencies and rates at national and regional levels from 1983 to 2032. The aim is that this monograph will be an important resource for health researchers and planners. Most importantly, it is hoped the monograph will: - provide evidence-based input for the development of public health policy priorities at the regional and national levels; and - guide public health officials in planning strategy including designing and evaluating preventive interventions and planning resources (treatment requirements) and infrastructure for future cancer control and care intended to reduce the burden of cancer in Canada.


TITRE: Incidence du cancer au Canada : tendances et projections (1983-2032). OBJET ET PUBLICS CIBLES: Chaque année, la publication Statistiques canadiennes sur le cancer donne une estimation du nombre de cas et des taux projetés pour les sièges de cancer courants pour l'année en cours au Canada, dans les provinces et les territoires. La présente monographie vient compléter la publication Statistiques canadiennes sur le cancer en fournissant des projections sur le nombre de nouveaux cas et les taux d'incidence de cancer à l'échelle régionale et nationale de 1983 à 2032. Elle se veut une ressource importante pour les chercheurs et les planificateurs du domaine de la santé. Plus important encore, nous espérons que cette monographie permettra : - de fournir des commentaires fondés sur des données probantes permettant l'élaboration de priorités stratégiques en matière de santé publique à l'échelle régionale et nationale; - de guider les responsables de la santé publique dans la planification d'une stratégie, notamment la conception et l'évaluation d'interventions préventives, ainsi que la planification des ressources (exigences relatives au traitement) et des infrastructures pour assurer la prestation future de soins de santé et de mesures de lutte contre le cancer en vue de réduire le fardeau de la maladie au Canada.


Assuntos
Neoplasias/epidemiologia , Neoplasias/patologia , Canadá/epidemiologia , Bases de Dados Factuais , Feminino , Previsões , Humanos , Incidência , Masculino , Neoplasias/terapia , Saúde Pública , Distribuição por Sexo , Análise de Sobrevida , Resultado do Tratamento
12.
Reprod Toxicol ; 50: 43-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25461904

RESUMO

A deterioration of human semen quality has been observed over recent decades. A possible explanation could be an increased exposure to environmental pollutants, including aluminum. Our aim was to measure the aluminum concentration in the semen of 62 patients and to carry out a preliminary evaluation on its impact on specific semen parameters. For each patient, semen analyses were performed according to WHO guidelines. A graphite furnace atomic absorption spectrometry method was used to determine semen aluminum concentration. A cytological analysis using an aluminum-specific fluor, lumogallion, was also performed. The mean aluminum concentration in human semen was 339 µg/L. Patients with oligozoospermia had a statistically higher aluminum concentration than others. No significant difference was observed for other semen parameters. Cytological analysis showed the presence of aluminum in spermatozoa. This study provided unequivocal evidence of high concentrations of aluminum in human semen and suggested possible implications for spermatogenesis and sperm count.


Assuntos
Alumínio/análise , Sêmen/química , Adulto , Humanos , Masculino , Microscopia de Fluorescência , Oligospermia/metabolismo
13.
Chronic Dis Inj Can ; 34(1): 64-8, 2014 Feb.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-24618383

RESUMO

The incidence of thyroid cancer is increasing more rapidly than that of any other cancer in Canada, while mortality has remained low and stable. In the last 10 years the number of thyroid cancer cases has increased 144% from 1709 to 4172 cases per year. Thyroid cancer is three times more common in females than males. 40% of thyroid cancers are diagnosed in Canadians under 45 years of age. Some of the apparent increase in incidence is likely due to improved and more widely available diagnostic techniques.


TITRE: Le cancer au Canada : Série de fiches d'information n° 1 - Le cancer de la thyroïde au Canada. RÉSUMÉ: Au Canada, l'incidence du cancer de la thyroïde croît plus rapidement que celle de tout autre cancer, mais le taux de mortalité est demeuré faible et stable. Au cours des dix dernières années, le nombre de cas de cancer de la thyroïde a augmenté de 144 %, passant de 1 709 à 4 172 cas par an. Le cancer de la thyroïde est trois fois plus fréquent chez la femme que chez l'homme. Quarante pour cent des cancers de la thyroïde ont été diagnostiqués chez les moins de 45 ans. Une partie de cette hausse apparente de l'incidence s'expliquerait par des techniques de diagnostic plus efficaces et plus largement accessibles.


Assuntos
Sistema de Registros , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Canadá/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Medição de Risco , Distribuição por Sexo , Análise de Sobrevida , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-23973608

RESUMO

The African cichlid, Pseudocrenilabrus multicolor victoriae is a eurytopic fish that exhibits high levels of developmental plasticity in response to dissolved oxygen availability. In this study, F1 offspring from three sites in the Mpanga River drainage of Western Uganda characterized by different dissolved oxygen (D.O.) regimes were reared under normoxic or hypoxic conditions. After 1 year, enzymes were measured to determine the tissue metabolic capacity of four different tissues: muscle, heart, brain and liver. The enzymes measured were pyruvate kinase [PK], lactate dehydrogenase [LDH], citrate synthase [CS], and cytochrome C oxidase [CCO], and an additional two, malate dehydrogenase (MDH) and fructose 1,6-bisphosphatase (FBPase), were examined in the liver only. Individuals reared under hypoxia exhibited elevated levels of LDH and CCO in the heart; and depressed activity levels of brain CS and liver CCO and MDH relative to normoxia-reared sibs. Results from this study demonstrate that long-term exposure to hypoxia during development can induce changes in the metabolic capacities of P. multicolor. This flexibility may be important in facilitating persistence in variable and/or novel environments, and in the face of increasing global hypoxia.


Assuntos
Ciclídeos/crescimento & desenvolvimento , Hipóxia/metabolismo , Oxigênio/metabolismo , Animais , Encéfalo/enzimologia , Ciclídeos/genética , Ciclídeos/metabolismo , Citrato (si)-Sintase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Frutose-Bifosfatase/metabolismo , Regulação Enzimológica da Expressão Gênica , Hipóxia/genética , L-Lactato Desidrogenase/metabolismo , Malato Desidrogenase/metabolismo , Músculos/enzimologia , Piruvato Quinase/metabolismo , Rios , Distribuição Tecidual
15.
Ecol Evol ; 3(6): 1495-506, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23789062

RESUMO

Population level response to hypoxia has become an issue of global significance because of increased frequency and intensity of hypoxic events worldwide, and the potential for global warming to exacerbate hypoxic stress. In this study, we sequenced two nuclear intronic regions and a single mitochondrial region across seven populations of the African cyprinid, Barbus neumayeri from two river drainages in Uganda: the Rwembaita Swamp-Njuguta River System and the Dura River. We then examined two indices of population structure, G ST and Jost's D, to detect links between oxygen availability and genetic variation and to determine if population genetic structure was associated with (i) dissolved oxygen regime (hypoxia or normoxia), (ii) geographical distance, or (iii) a combination of dissolved oxygen regime and geographical distance. Our results indicate that over a large scale (between drainages), geographical distance significantly affects the genetic structure of populations. However, within a single drainage, dissolved oxygen regime plays a key role in determining the genetic structure of populations. Within the Rwembaita-Njuguta system, gene flow was high between locations of similar oxygen regimes, but low between areas characterized by divergent oxygen regimes. Interestingly, G ST analyses appear to yield less realistic measures of population structure than Jost's D, suggesting that caution must be taken when interpreting and comparing the results from different studies. These results support the idea that aquatic dissolved oxygen can act as a selective force limiting gene flow among populations of aquatic species and therefore should be considered when implementing conservation plans and assessing environmental impact of human activities.

16.
Ann Oncol ; 24(1): 245-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22831983

RESUMO

BACKGROUND: Dietary glycemic index (GI) and glycemic load (GL) have been related to the risk of selected cancers, but the issue remains open. PATIENTS AND METHODS: Mailed questionnaires were completed between 1994 and 1997 in eight Canadian provinces for incident, histologically confirmed cases of the stomach (n=1182), colon (n=1727), rectum (n=1447), liver (n=309), pancreas (n=628), lung (n=3341), breast (n=2362), ovary (n=442), prostate (n=1799), testis (n=686), kidney (n=1345), bladder (n=1029), brain (n=1009), non-Hodgkin's lymphomas (NHL, n=1666), leukemias (n=1069), multiple myelomas (n=343), and 5039 population controls. Dietary information on eating habits 2 years before participants' enrollment in the study was obtained using a validated food frequency questionnaire (FFQ). Odds ratios (ORs) and 95% confidence intervals (CI) were derived by unconditional logistic regression including recognized confounding factors. RESULTS: Dietary GI was positively associated with the risk of prostate cancer (OR, 1.26 for the highest versus the lowest quartile). A higher dietary GL significantly increased the risk of colorectal (OR, 1.28), rectal (OR, 1.44) and pancreatic (OR, 1.41) cancers. No other significant associations were found. CONCLUSIONS: Our findings suggest that a diet high in GI and GL is associated with increased risk of selected cancers.


Assuntos
Carboidratos da Dieta/administração & dosagem , Glucose/administração & dosagem , Índice Glicêmico , Neoplasias/etiologia , Índice de Massa Corporal , Estudos de Casos e Controles , Carboidratos da Dieta/efeitos adversos , Feminino , Glucose/efeitos adversos , Humanos , Masculino
17.
Artigo em Inglês | MEDLINE | ID: mdl-23123804

RESUMO

This study describes the metabolic capacities of the African cichlid Pseudocrenilabrus multicolor victoriae from four sites in Uganda, East Africa. Fish were captured during the dry season, from two aquatic systems in different regions (Lake Nabugabo and Mpanga River). Within the Lake Nabugabo region, individuals were sampled from Lake Kayanja (normoxic) and Lwamunda Swamp (hypoxic); within the Mpanga River system, individuals were sampled from Bunoga and Kahunge (characterized by seasonal variation in dissolved oxygen (D.O.)). Enzyme activity levels of pyruvate kinase, lactate dehydrogenase, citrate synthase, and cytochrome C oxidase were measured in four tissues: white skeletal muscle, heart, brain, and liver. Two additional enzymes were measured in the liver, malate dehydrogenase and fructose 1,6-bisphosphatase. Regional differences between enzyme activities in most tissues were evident; however, little variation was observed between two sites within a region despite differences in D.O. In general, P. multicolor from the Mpanga River system displayed greater anaerobic enzyme activity in white skeletal muscle, lower gluconeogenic enzyme activity in the liver, and an overall higher enzyme activity in the heart and brain tissues than fish from the Nabugabo region. The latter may reflect a long-term adaptation to low-oxygen conditions at the metapopulation level in the Nabugabo region.


Assuntos
Ciclídeos/metabolismo , Enzimas/metabolismo , Animais , Tamanho Corporal , Ciclídeos/anatomia & histologia , Ciclídeos/genética , Ecossistema , Enzimas/genética , Regulação Enzimológica da Expressão Gênica , Geografia , Lagos , Especificidade de Órgãos , Oxigênio/metabolismo , Rios
18.
Ann Oncol ; 23(2): 491-500, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21543628

RESUMO

BACKGROUND: This study assesses the association between dietary cholesterol intake and the risk of various cancers. PATIENTS AND METHODS: Mailed questionnaires were completed between 1994 and 1997 in eight Canadian provinces by 1182 incident histologically confirmed cases of the stomach, 1727 of the colon, 1447 of the rectum, 628 of the pancreas, 3341 of the lung, 2362 of the breast, 442 of the ovary, 1799 of the prostate, 686 of the testis, 1345 of the kidney, 1029 of the bladder, 1009 of the brain, 1666 non-Hodgkin's lymphomas (NHL), 1069 leukemia and 5039 population controls. Information on dietary habits and nutrition intake were obtained using a food frequency questionnaire, which provided data on eating habits 2 years before the study. Odds ratios (ORs) were derived by unconditional logistic regression to adjust for total energy intake and other potential confounding factors. RESULTS: Dietary cholesterol was positively associated with the risk of cancers of the stomach, colon, rectum, pancreas, lung, breast (mainly postmenopausal), kidney, bladder and NHL: the ORs for the highest versus the lowest quartile ranged from 1.4 to 1.7. In contrast, cholesterol intake was inversely associated with prostate cancer. CONCLUSIONS: Our findings add to the evidence that high cholesterol intake is linked to increased risk of various cancers. A diet low in cholesterol may play a role in the prevention of several cancers.


Assuntos
Colesterol na Dieta/efeitos adversos , Neoplasias/epidemiologia , Sistema de Registros , Adulto , Idoso , Canadá/epidemiologia , Dieta , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Razão de Chances , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
19.
BMC Ecol ; 11: 2, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-21251277

RESUMO

BACKGROUND: Oxygen availability in aquatic habitats is a major environmental factor influencing the ecology, behaviour, and physiology of fishes. This study evaluates the contribution of source population and hypoxic acclimatization of the African fish, Barbus neumayeri, in determining growth and tissue metabolic enzyme activities. Individuals were collected from two sites differing dramatically in concentration of dissolved oxygen (DO), Rwembaita Swamp (annual average DO 1.35 mgO2 L(-1)) and Inlet Stream West (annual average DO 5.58 mgO2 L(-1)) in Kibale National Park, Uganda, and reciprocally transplanted using a cage experiment in the field, allowing us to maintain individuals under natural conditions of oxygen, food availability, and flow. Fish were maintained under these conditions for four weeks and sampled for growth rate and the activities of phosphofructokinase (PFK), lactate dehydrogenase (LDH), citrate synthase (CS), and cytochrome c oxidase (CCO) in four tissues, liver, heart, brain, and skeletal muscle. RESULTS: Acclimatization to the low DO site resulted in lower growth rates, lower activities of the aerobic enzyme CCO in heart, and higher activities of the glycolytic enzyme PFK in heart and skeletal muscle. The activity of LDH in liver tissue was correlated with site of origin, being higher in fish collected from a hypoxic habitat, regardless of acclimatization treatment. CONCLUSIONS: Our results suggest that the influence of site of origin and hypoxic acclimatization in determining enzyme activity differs among enzymes and tissues, but both factors contribute to higher glycolytic capacity and lower aerobic capacity in B. neumayeri under naturally-occurring conditions of oxygen limitation.


Assuntos
Cyprinidae/fisiologia , Ecossistema , Oxigênio/metabolismo , Aclimatação , Estruturas Animais/enzimologia , Animais , Citrato (si)-Sintase/metabolismo , Proteínas de Peixes/metabolismo , Fosfofrutoquinases/metabolismo
20.
J Med Genet ; 45(9): 583-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18762571

RESUMO

BACKGROUND: Imprinted genes, many of which are involved in development, are marked during gametogenesis to allow their parent-of-origin specific expression, and DNA methylation at CpG islands is part of this epigenetic mark. Maternal imprint is apposed on oocyte during growth and maturation. Factors interfering with normal oocyte differentiation such as gonadotrophin stimulation and in vitro maturation (IVM) may possibly alter imprint resetting. METHODS: We examined the methylation of the KCNQ1OT1 differentially methylated region (KvDMR1) in human oocytes at different stages of their development: germinal vesicle (GV), metaphase I (MI) or metaphase II (MII). RESULTS: About 60% of alleles were fully methylated in GV oocytes and that full imprint is acquired in most MII oocytes. Similarly to in vivo, de novo methylation of DNA occurred in vitro during oocyte maturation. Following in vitro culture for 28 h, GV and MI oocytes are significantly more methylated when they are obtained from natural cycles than from patients undergoing gonadotrophin stimulation. CONCLUSION: This observation suggests that hyperstimulation likely recruits young follicles that are unable to acquire imprint at KvDMR1 during the course of the maturing process.


Assuntos
Ilhas de CpG , Metilação de DNA , Impressão Genômica , Oócitos/metabolismo , Humanos , Oócitos/citologia , Indução da Ovulação , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética
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