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1.
J Insect Sci ; 19(3)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31115475

RESUMO

Dendroctonus bark beetles (Scolytinae) are one of the most important disturbance agents of coniferous forests in North and Central America. These beetles spend their lives almost entirely under the tree bark, and their survival and reproductive success depend on their ability to overcome the toxic effect of the trees' oleoresin. The cytochromes P450 (CYPs) are associated with the detoxification process of xenobiotics, as well as other physiological processes. Different cytochromes (families 4, 6, and 9) in the Dendroctonus species have been expressed under several experimental conditions; nevertheless, the expression time-course of these genes is unknown. To explore the induction speed of CYPs, we evaluated the relative expression of the CYP6BW5, CYP6DG1, CYP6DJ2, CYP9Z18, and CYP9Z20 genes at the early hours of drilling and settling into a tree (1, 2, 4, 6, 8, 12, 18 h) both in females and males, solitary or paired, of the bark beetle Dendroctonus rhizophagus Thomas and Bright. Our findings show that the five genes were rapidly overexpressed in the early hours (1 to 6 h) in both sexes and in solitary and paired conditions, suggesting their participation in the detoxification process. Additionally, the CYPs expression shows up- and down-regulation patterns through these short times, suggesting their probable participation in other physiological processes as the biosynthesis of hormones, pheromones or compounds related to reproduction.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Gorgulhos/enzimologia , Animais , Sistema Enzimático do Citocromo P-450/genética , Comportamento Alimentar , Feminino , Masculino , Árvores , Gorgulhos/genética
2.
J Imaging ; 9(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37504821

RESUMO

Bees play a critical role in pollination and food production, so their preservation is essential, particularly highlighting the importance of detecting diseases in bees early. The Varroa destructor mite is the primary factor contributing to increased viral infections that can lead to hive mortality. This study presents an innovative method for identifying Varroa destructors in honey bees using multichannel Legendre-Fourier moments. The descriptors derived from this approach possess distinctive characteristics, such as rotation and scale invariance, and noise resistance, allowing the representation of digital images with minimal descriptors. This characteristic is advantageous when analyzing images of living organisms that are not in a static posture. The proposal evaluates the algorithm's efficiency using different color models, and to enhance its capacity, a subdivision of the VarroaDataset is used. This enhancement allows the algorithm to process additional information about the color and shape of the bee's legs, wings, eyes, and mouth. To demonstrate the advantages of our approach, we compare it with other deep learning methods, in semantic segmentation techniques, such as DeepLabV3, and object detection techniques, such as YOLOv5. The results suggest that our proposal offers a promising means for the early detection of the Varroa destructor mite, which could be an essential pillar in the preservation of bees and, therefore, in food production.

3.
PLoS Genet ; 5(3): e1000407, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19300474

RESUMO

Mitochondria are central to many cellular processes including respiration, ion homeostasis, and apoptosis. Using computational predictions combined with traditional quantitative experiments, we have identified 100 proteins whose deficiency alters mitochondrial biogenesis and inheritance in Saccharomyces cerevisiae. In addition, we used computational predictions to perform targeted double-mutant analysis detecting another nine genes with synthetic defects in mitochondrial biogenesis. This represents an increase of about 25% over previously known participants. Nearly half of these newly characterized proteins are conserved in mammals, including several orthologs known to be involved in human disease. Mutations in many of these genes demonstrate statistically significant mitochondrial transmission phenotypes more subtle than could be detected by traditional genetic screens or high-throughput techniques, and 47 have not been previously localized to mitochondria. We further characterized a subset of these genes using growth profiling and dual immunofluorescence, which identified genes specifically required for aerobic respiration and an uncharacterized cytoplasmic protein required for normal mitochondrial motility. Our results demonstrate that by leveraging computational analysis to direct quantitative experimental assays, we have characterized mutants with subtle mitochondrial defects whose phenotypes were undetected by high-throughput methods.


Assuntos
Mitocôndrias/genética , Proteínas/fisiologia , Saccharomyces cerevisiae/ultraestrutura , Respiração Celular/genética , Citoplasma/química , Genes Mitocondriais , Proteínas Mitocondriais , Proteínas Mutantes , Mutação , Proteínas/genética , Proteômica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
4.
J Pediatr Adolesc Gynecol ; 33(1): 53-57, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542369

RESUMO

STUDY OBJECTIVE: One concern regarding long-acting reversible contraceptive (LARC) use among female adolescents is the potential for sexually transmitted infection acquisition. Few studies investigate chlamydia infection among adolescent LARC users compared with other hormonal contraceptive method (non-LARC) users. We hypothesized that incident chlamydia infection would be similar in these 2 groups and that it would not be associated with adolescent LARC use. DESIGN, SETTING, AND PARTICIPANTS: Secondary data analysis of electronic health records of adolescents who started using LARC (n = 152) and non-LARC methods (n = 297) at 6 New York City school-based health centers between March 2015 and March 2017. INTERVENTIONS AND MAIN OUTCOME MEASURES: Demographic characteristics, sexual risk factors, and occurrence of chlamydia infection over a period of 1 year were compared in the 2 groups using χ2 tests and t tests. Multivariable logistic regression was used to test the association between LARC use and chlamydia infection adjusting for relevant covariates. RESULTS: Among 422 adolescent patients tested the year after method initiation, 48 (11.4%) had at least 1 positive chlamydia test. The proportions of LARC users and non-LARC users with chlamydia infection were not statistically significantly different (10.9% vs 11.6%; P = .82). Multivariable analysis showed that LARC use was not associated with greater chlamydia risk (adjusted odds ratio, 0.84; 95% confidence interval, 0.41-1.43). CONCLUSION: Adolescent LARC users did not have significantly higher chlamydia infection occurrence compared with non-LARC users the year after method initiation. Concern for chlamydial infection should prompt recommending condom use but should not be a barrier to recommending adolescent LARC use.


Assuntos
Infecções por Chlamydia/epidemiologia , Contracepção Reversível de Longo Prazo/estatística & dados numéricos , Adolescente , Estudos de Casos e Controles , Infecções por Chlamydia/prevenção & controle , Contraceptivos Hormonais/administração & dosagem , Feminino , Humanos , Cidade de Nova Iorque/epidemiologia , Gravidez , Comportamento Sexual
5.
Front Microbiol ; 9: 77, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29441055

RESUMO

Symbioses between plants and microorganims have been fundamental in the evolution of both groups. The endophytic bacteria associated with conifers have been poorly studied in terms of diversity, ecology, and function. Coniferous trees of the genera Larix, Pseudotsugae, Picea and mainly Pinus, are hosts of many insects, including bark beetles and especially the Dendroctonus species. These insects colonize and kill these trees during their life cycle. Several bacteria detected in the gut and cuticle of these insects have been identified as endophytes in conifers. In this study, we characterized and compared the endophytic bacterial diversity in roots, phloem and bark of non-attacked saplings of Pinus arizonica and P. durangensis using 16S rRNA gene pyrosequencing. In addition, we evaluated the degree of taxonomic relatedness, and the association of metabolic function profiles of communities of endophytic bacteria and previously reported gut bacterial communities of D. rhizophagus; a specialized bark beetle that colonizes and kills saplings of these pine species. Our results showed that both pine species share a similar endophytic community. A total of seven bacterial phyla, 14 classes, 26 orders, 43 families, and 51 genera were identified. Enterobacteriaceae was the most abundant family across all samples, followed by Acetobacteraceae and Acidobacteriaceae, which agree with previous studies performed in other pines and conifers. Endophytic communities and that of the insect gut were significantly different, however, the taxonomic relatedness of certain bacterial genera of pines and insect assemblages suggested that some bacteria from pine tissues might be the same as those in the insect gut. Lastly, the metabolic profile using PICRUSt showed there to be a positive association between communities of both pines and insect gut. This study represents the baseline into the knowledge of the endophytic bacterial communities of two of the major hosts affected by D. rhizophagus.

6.
J Int Assoc Provid AIDS Care ; 16(6): 579-587, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28895487

RESUMO

With the introduction of combination antiretroviral therapy (ART) worldwide, youth with perinatal HIV infection are increasingly surviving childhood and transitioning to adult care. Although a normal life span is anticipated posttransition, successful transition to adult HIV care has proven difficult, with worse outcomes posttransition than in pediatric and adult care. This study is a qualitative analysis of data from 4 focus groups of pre- and posttransition patients, caregivers, and healthcare providers in the Dominican Republic at an institution that provides comprehensive treatment including ART for HIV-infected persons of all ages. All groups discussed the problems and challenges that patients, caregivers, and providers experience while living the transition process and beyond. Five major themes emerged: the trauma of transition itself, ART adherence, experience and impact of stigma, social supports and barriers, and recommendations for improving outcomes. Participants' insights offered approaches for a versatile structured transition process.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Cuidadores , Infecções por HIV/tratamento farmacológico , Transição para Assistência do Adulto , Adolescente , Adulto , Idoso , República Dominicana , Feminino , Grupos Focais , Infecções por HIV/transmissão , Pessoal de Saúde , Humanos , Transmissão Vertical de Doenças Infecciosas , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Trauma Psicológico , Pesquisa Qualitativa , Estigma Social , Apoio Social , Adulto Jovem
7.
Diabetes ; 62(12): 4052-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23990360

RESUMO

Hepatic Notch signaling is inappropriately activated in obese/insulin-resistant mouse models. Genetic or pharmacologic inhibition of hepatic Notch signaling in obese mice simultaneously improves glucose tolerance and reduces hepatic triglyceride content. As such, we predicted that Notch signaling in human liver would be positively associated with insulin resistance and hepatic steatosis. Here, we systematically survey Notch signaling in liver biopsy specimens, and show active Notch signaling in lean and obese adults, with expression of multiple Notch receptors and ligands. In morbidly obese patients undergoing bariatric surgery, we show that Notch activation positively correlates with glucose-6-phosphatase (G6PC) and phosphoenolpyruvate carboxykinase (PCK1) expression, key regulators of hepatic glucose output. We used immunofluorescence to identify active Notch signaling in hepatocytes and show highest activity in hyperglycemia, which we confirmed is a direct effect of hyperglycemia and insulin resistance. In a validation cohort of leaner individuals undergoing percutaneous liver biopsy for suspected nonalcoholic fatty liver disease (NAFLD), Notch activity showed independent positive association with insulin resistance and hepatic steatosis. Notably, Notch activity showed stronger correlation with the NAFLD activity score and alanine aminotransferase levels than with steatosis alone, suggesting that Notch activity is associated with nonalcoholic steatohepatitis. In summary, this study establishes that Notch signaling is activated in and may represent a therapeutic target for patients with obesity-related liver disease.


Assuntos
Fígado Gorduroso/metabolismo , Resistência à Insulina/fisiologia , Fígado/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Adulto , Alanina Transaminase/metabolismo , Fígado Gorduroso/complicações , Fígado Gorduroso/patologia , Feminino , Glucose-6-Fosfatase/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Hiperglicemia/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Obesidade/complicações , Obesidade/metabolismo , Obesidade/patologia , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo
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