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1.
Blood ; 142(14): 1185-1192, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37506341

RESUMO

Germ line variants in the DDX41 gene have been linked to myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) development. However, the risks associated with different variants remain unknown, as do the basis of their leukemogenic properties, impact on steady-state hematopoiesis, and links to other cancers. Here, we investigate the frequency and significance of DDX41 variants in 454 792 United Kingdom Biobank (UKB) participants and identify 452 unique nonsynonymous DNA variants in 3538 (1/129) individuals. Many were novel, and the prevalence of most varied markedly by ancestry. Among the 1059 individuals with germ line pathogenic variants (DDX41-GPV) 34 developed MDS/AML (odds ratio, 12.3 vs noncarriers). Of these, 7 of 218 had start-lost, 22 of 584 had truncating, and 5 of 257 had missense (odds ratios: 12.9, 15.1, and 7.5, respectively). Using multivariate logistic regression, we found significant associations of DDX41-GPV with MDS, AML, and family history of leukemia but not lymphoma, myeloproliferative neoplasms, or other cancers. We also report that DDX41-GPV carriers do not have an increased prevalence of clonal hematopoiesis (CH). In fact, CH was significantly more common before sporadic vs DDX41-mutant MDS/AML, revealing distinct evolutionary paths. Furthermore, somatic mutation rates did not differ between sporadic and DDX41-mutant AML genomes, ruling out genomic instability as a driver of the latter. Finally, we found that higher mean red cell volume (MCV) and somatic DDX41 mutations in blood DNA identify DDX41-GPV carriers at increased MDS/AML risk. Collectively, our findings give new insights into the prevalence and cognate risks associated with DDX41 variants, as well as the clonal evolution and early detection of DDX41-mutant MDS/AML.


Assuntos
Deficiência de GATA2 , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Prevalência , RNA Helicases DEAD-box/genética , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/genética , DNA
2.
Cancer Cell Int ; 23(1): 314, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066541

RESUMO

BACKGROUND: This study aims to compare the technical performance of Abbott's UroVysion and Biocare's CytoFISH urine cytology probe panel and position the CytoFISH probe panel as an alternative to UroVysion. The CytoFISH probe panel was developed based on clinically sensitive chromosomes found to be amplified in bladder cancers, as well as a locus-specific probe also seen to be amplified in bladder tumors. After extensive testing comparing CytoFISH to UroVysion, we present here our findings for the two assays. MATERIALS AND METHODS: A total of 216 cases representing a mix of male (ages 36-99) and female (ages 46-91) patients were assayed with both probe sets. The CytoFISH and UroVysion probe panels were tested in accordance with the UroVysion procedure, as outlined in the manufacturer's supplied package insert with the following exception: the probe volume used was 3µL for UroVysion and 5µL for CytoFISH. RESULTS: The scoring used for the CytoFISH and UroVysion assays revealed a 95% concordance, suggesting that Biocare's CytoFISH Test has at least the same clinical sensitivity and specificity as claimed by the Abbott UroVysion Kit. We found that the CytoFISH 5p15.2 locus-specific probe was easier to score than UroVysion's 9p21 deletion. CONCLUSION: The high rate of concordance between the two assays suggests that Biocare's CytoFISH assay is a robust alternative to Abbott's UroVysion in the diagnosis and monitoring of bladder carcinoma.

3.
J Neurosci ; 39(39): 7748-7758, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31477568

RESUMO

Humans have bred different lineages of domestic dogs for different tasks such as hunting, herding, guarding, or companionship. These behavioral differences must be the result of underlying neural differences, but surprisingly, this topic has gone largely unexplored. The current study examined whether and how selective breeding by humans has altered the gross organization of the brain in dogs. We assessed regional volumetric variation in MRI studies of 62 male and female dogs of 33 breeds. Neuroanatomical variation is plainly visible across breeds. This variation is distributed nonrandomly across the brain. A whole-brain, data-driven independent components analysis established that specific regional subnetworks covary significantly with each other. Variation in these networks is not simply the result of variation in total brain size, total body size, or skull shape. Furthermore, the anatomy of these networks correlates significantly with different behavioral specialization(s) such as sight hunting, scent hunting, guarding, and companionship. Importantly, a phylogenetic analysis revealed that most change has occurred in the terminal branches of the dog phylogenetic tree, indicating strong, recent selection in individual breeds. Together, these results establish that brain anatomy varies significantly in dogs, likely due to human-applied selection for behavior.SIGNIFICANCE STATEMENT Dog breeds are known to vary in cognition, temperament, and behavior, but the neural origins of this variation are unknown. In an MRI-based analysis, we found that brain anatomy covaries significantly with behavioral specializations such as sight hunting, scent hunting, guarding, and companionship. Neuroanatomical variation is not simply driven by brain size, body size, or skull shape, and is focused in specific networks of regions. Nearly all of the identified variation occurs in the terminal branches of the dog phylogenetic tree, indicating strong, recent selection in individual breeds. These results indicate that through selective breeding, humans have significantly altered the brains of different lineages of domestic dogs in different ways.


Assuntos
Encéfalo/anatomia & histologia , Cães/fisiologia , Sistema Nervoso/anatomia & histologia , Animais , Comportamento Animal , Tamanho Corporal , Encéfalo/diagnóstico por imagem , Cruzamento , Feminino , Variação Genética , Vínculo Humano-Animal , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Sistema Nervoso/diagnóstico por imagem , Tamanho do Órgão , Filogenia , Comportamento Predatório , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , Olfato/fisiologia , Especificidade da Espécie
4.
Brief Bioinform ; 18(6): 1044-1056, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27585944

RESUMO

The unprecedented advances in technology and scientific research over the past few years have provided the scientific community with new and more complex forms of data. Large data sets collected from single groups or cross-institution consortiums containing hundreds of omic and clinical variables corresponding to thousands of patients are becoming increasingly commonplace in the research setting. Before any core analyses are performed, visualization often plays a key role in the initial phases of research, especially for projects where no initial hypotheses are dominant. Proper visualization of data at a high level facilitates researcher's abilities to find trends, identify outliers and perform quality checks. In addition, research has uncovered the important role of visualization in data analysis and its implied benefits facilitating our understanding of disease and ultimately improving patient care. In this work, we present a review of the current landscape of existing tools designed to facilitate the visualization of multidimensional data in translational research platforms. Specifically, we reviewed the biomedical literature for translational platforms allowing the visualization and exploration of clinical and omics data, and identified 11 platforms: cBioPortal, interactive genomics patient stratification explorer, Igloo-Plot, The Georgetown Database of Cancer Plus, tranSMART, an unnamed data-cube-based model supporting heterogeneous data, Papilio, Caleydo Domino, Qlucore Omics, Oracle Health Sciences Translational Research Center and OmicsOffice® powered by TIBCO Spotfire. In a health sector continuously witnessing an increase in data from multifarious sources, visualization tools used to better grasp these data will grow in their importance, and we believe our work will be useful in guiding investigators in similar situations.


Assuntos
Biologia Computacional/métodos , Gráficos por Computador , Bases de Dados Factuais , Software , Estatística como Assunto/métodos , Pesquisa Translacional Biomédica , Genômica , Humanos , Armazenamento e Recuperação da Informação
5.
Proc Natl Acad Sci U S A ; 112(11): E1191-200, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25733880

RESUMO

The human spliceosome is a large ribonucleoprotein complex that catalyzes pre-mRNA splicing. It consists of five snRNAs and more than 200 proteins. Because of this complexity, much work has focused on the Saccharomyces cerevisiae spliceosome, viewed as a highly simplified system with fewer than half as many splicing factors as humans. Nevertheless, it has been difficult to ascribe a mechanistic function to individual splicing factors or even to discern which are critical for catalyzing the splicing reaction. We have identified and characterized the splicing machinery from the red alga Cyanidioschyzon merolae, which has been reported to harbor only 26 intron-containing genes. The U2, U4, U5, and U6 snRNAs contain expected conserved sequences and have the ability to adopt secondary structures and form intermolecular base-pairing interactions, as in other organisms. C. merolae has a highly reduced set of 43 identifiable core splicing proteins, compared with ∼90 in budding yeast and ∼140 in humans. Strikingly, we have been unable to find a U1 snRNA candidate or any predicted U1-associated proteins, suggesting that splicing in C. merolae may occur without the U1 small nuclear ribonucleoprotein particle. In addition, based on mapping the identified proteins onto the known splicing cycle, we propose that there is far less compositional variability during splicing in C. merolae than in other organisms. The observed reduction in splicing factors is consistent with the elimination of spliceosomal components that play a peripheral or modulatory role in splicing, presumably retaining those with a more central role in organization and catalysis.


Assuntos
Rodófitas/metabolismo , Spliceossomos/metabolismo , Proteínas de Algas/genética , Proteínas de Algas/metabolismo , Pareamento de Bases/genética , Humanos , Imunoprecipitação , Íntrons/genética , Modelos Biológicos , Conformação de Ácido Nucleico , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Estabilidade de RNA/genética , RNA Nuclear Pequeno/química , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , Rodófitas/genética
7.
J Immunol ; 194(3): 1131-40, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25556247

RESUMO

The transcription factor T-bet has been most prominently linked to NK and T cell production of IFN-γ, a cytokine required for the control of a diverse array of intracellular pathogens. Indeed, in mice challenged with the parasite Toxoplasma gondii, NK and T cell responses are characterized by marked increases of T-bet expression. Unexpectedly, T-bet(-/-) mice infected with T. gondii develop a strong NK cell IFN-γ response that controls parasite replication at the challenge site, but display high parasite burdens at secondary sites colonized by T. gondii and succumb to infection. The loss of T-bet had a modest effect on T cell production of IFN-γ but did not impact on the generation of parasite-specific T cells. However, the absence of T-bet resulted in lower T cell expression of CD11a, Ly6C, KLRG-1, and CXCR3 and fewer parasite-specific T cells at secondary sites of infection, associated with a defect in parasite control at these sites. Together, these data highlight T-bet-independent pathways to IFN-γ production and reveal a novel role for this transcription factor in coordinating the T cell responses necessary to control this infection in peripheral tissues.


Assuntos
Resistência à Doença/genética , Resistência à Doença/imunologia , Imunidade , Infecções/genética , Infecções/imunologia , Proteínas com Domínio T/genética , Animais , Modelos Animais de Doenças , Expressão Gênica , Predisposição Genética para Doença , Imunidade Celular , Imunidade Inata , Imunofenotipagem , Infecções/metabolismo , Infecções/parasitologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Knockout , Fenótipo , Proteínas com Domínio T/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Toxoplasma/imunologia , Toxoplasmose Animal/genética , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/metabolismo
8.
BMC Cancer ; 16: 611, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27502180

RESUMO

BACKGROUND: Glioblastoma (GBM) tumors exhibit strong phenotypic differences that can be quantified using magnetic resonance imaging (MRI), but the underlying biological drivers of these imaging phenotypes remain largely unknown. An Imaging-Genomics analysis was performed to reveal the mechanistic associations between MRI derived quantitative volumetric tumor phenotype features and molecular pathways. METHODS: One hundred fourty one patients with presurgery MRI and survival data were included in our analysis. Volumetric features were defined, including the necrotic core (NE), contrast-enhancement (CE), abnormal tumor volume assessed by post-contrast T1w (tumor bulk or TB), tumor-associated edema based on T2-FLAIR (ED), and total tumor volume (TV), as well as ratios of these tumor components. Based on gene expression where available (n = 91), pathway associations were assessed using a preranked gene set enrichment analysis. These results were put into context of molecular subtypes in GBM and prognostication. RESULTS: Volumetric features were significantly associated with diverse sets of biological processes (FDR < 0.05). While NE and TB were enriched for immune response pathways and apoptosis, CE was associated with signal transduction and protein folding processes. ED was mainly enriched for homeostasis and cell cycling pathways. ED was also the strongest predictor of molecular GBM subtypes (AUC = 0.61). CE was the strongest predictor of overall survival (C-index = 0.6; Noether test, p = 4x10(-4)). CONCLUSION: GBM volumetric features extracted from MRI are significantly enriched for information about the biological state of a tumor that impacts patient outcomes. Clinical decision-support systems could exploit this information to develop personalized treatment strategies on the basis of noninvasive imaging.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Redes Reguladoras de Genes , Genômica/métodos , Glioblastoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Apoptose , Neoplasias Encefálicas/genética , Ciclo Celular , Sistemas de Apoio a Decisões Clínicas , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Humanos , Fenótipo , Transdução de Sinais , Análise de Sobrevida
9.
Neuropathology ; 36(3): 270-82, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26577803

RESUMO

Alzheimer's disease (AD) is a progressive neurological disorder that affects more than 30 million people worldwide. While various dementia-related losses in cognitive functioning are its hallmark clinical symptoms, ultimate diagnosis is based on manual neuropathological assessments using various schemas, including Braak staging, CERAD (Consortium to Establish a Registry for Alzheimer's Disease) and Thal phase scoring. Since these scoring systems are based on subjective assessment, there is inevitably some degree of variation between readers, which could affect ultimate neuropathology diagnosis. Here, we report a pilot study investigating the applicability of computer-driven image analysis for characterizing neuropathological features, as well as its potential to supplement or even replace manually derived ratings commonly performed in medical settings. In this work, we quantitatively measured amyloid beta (Aß) plaque in various brain regions from 34 patients using a robust digital quantification algorithm. We next verified these digitally derived measures to the manually derived pathology ratings using correlation and ordinal logistic regression methods, while also investigating the association with other AD-related neuropathology scoring schema commonly used at autopsy, such as Braak and CERAD. In addition to successfully verifying our digital measurements of Aß plaques with respective categorical measurements, we found significant correlations with most AD-related scoring schemas. Our results demonstrate the potential for digital analysis to be adapted to more complex staining procedures commonly used in neuropathological diagnosis. As the efficiency of scanning and digital analysis of histology images increases, we believe that the basis of our semi-automatic approach may better standardize quantification of neuropathological changes and AD diagnosis, ultimately leading to a more comprehensive understanding of neurological disorders and more efficient patient care.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Diagnóstico por Computador/métodos , Idoso , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
10.
Gen Dent ; 64(5): 20-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27599276

RESUMO

Sonication technology has recently been touted to decrease composite viscosity during delivery and may allow better cavity preparation adaptation and minimize voids. The purpose of this investigation was to evaluate the difference between conventional, hand-placed, incremental application of a standard hybrid resin-based composite (RBC) and sonicated application of a bulk-fill RBC in box-type and cylindrical cavity preparations. Experimental restorations were fabricated using molds of box-type or cylindrical preparations. For bulk-filled specimens, a single compule of bulk-fill composite was dispensed with a sonic handpiece. The conventional hybrid material was placed in 3 increments (2 mm, 2 mm, and 1 mm). Microfocus x-ray computed tomography was used to analyze voids for percentage and total volume porosity as well as number of actual pores. An analysis of variance indicated that RBC restorations that were applied to cylindrical cavities using a sonicated bulk-filled application method exhibited significantly less porosity (1.42%; P < 0.001) than incrementally placed cylindrical restorations (2.87%); sonicated bulk-filled, cube-shaped restorations (3.12%); and incrementally placed cube-shaped restorations (5.16%). When the groups were subcategorized into the specific characteristics of shape (cube vs cylinder) and application method (bulk vs incremental), the cylindrical group, which included both bulk-filled and incrementally placed specimens, demonstrated significantly less porosity (2.00%; P < 0.001) than other groups. Restorations that were incrementally placed into cube-shaped cavities produced the largest amount of porosity.


Assuntos
Resinas Compostas/uso terapêutico , Restauração Dentária Permanente/métodos , Microtomografia por Raio-X , Resinas Compostas/administração & dosagem , Preparo da Cavidade Dentária/métodos , Humanos , Porosidade , Microtomografia por Raio-X/métodos
11.
Lab Invest ; 95(4): 366-76, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25599536

RESUMO

Technological advances in computing, imaging, and genomics have created new opportunities for exploring relationships between histology, molecular events, and clinical outcomes using quantitative methods. Slide scanning devices are now capable of rapidly producing massive digital image archives that capture histological details in high resolution. Commensurate advances in computing and image analysis algorithms enable mining of archives to extract descriptions of histology, ranging from basic human annotations to automatic and precisely quantitative morphometric characterization of hundreds of millions of cells. These imaging capabilities represent a new dimension in tissue-based studies, and when combined with genomic and clinical endpoints, can be used to explore biologic characteristics of the tumor microenvironment and to discover new morphologic biomarkers of genetic alterations and patient outcomes. In this paper, we review developments in quantitative imaging technology and illustrate how image features can be integrated with clinical and genomic data to investigate fundamental problems in cancer. Using motivating examples from the study of glioblastomas (GBMs), we demonstrate how public data from The Cancer Genome Atlas (TCGA) can serve as an open platform to conduct in silico tissue-based studies that integrate existing data resources. We show how these approaches can be used to explore the relation of the tumor microenvironment to genomic alterations and gene expression patterns and to define nuclear morphometric features that are predictive of genetic alterations and clinical outcomes. Challenges, limitations, and emerging opportunities in the area of quantitative imaging and integrative analyses are also discussed.


Assuntos
Técnicas Genéticas , Genômica , Histocitoquímica , Neoplasias , Humanos , Neoplasias/química , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/patologia
12.
Neuroradiology ; 57(12): 1227-37, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26337765

RESUMO

INTRODUCTION: MR imaging can noninvasively visualize tumor phenotype characteristics at the macroscopic level. Here, we investigated whether somatic mutations are associated with and can be predicted by MRI-derived tumor imaging features of glioblastoma (GBM). METHODS: Seventy-six GBM patients were identified from The Cancer Imaging Archive for whom preoperative T1-contrast (T1C) and T2-FLAIR MR images were available. For each tumor, a set of volumetric imaging features and their ratios were measured, including necrosis, contrast enhancing, and edema volumes. Imaging genomics analysis assessed the association of these features with mutation status of nine genes frequently altered in adult GBM. Finally, area under the curve (AUC) analysis was conducted to evaluate the predictive performance of imaging features for mutational status. RESULTS: Our results demonstrate that MR imaging features are strongly associated with mutation status. For example, TP53-mutated tumors had significantly smaller contrast enhancing and necrosis volumes (p = 0.012 and 0.017, respectively) and RB1-mutated tumors had significantly smaller edema volumes (p = 0.015) compared to wild-type tumors. MRI volumetric features were also found to significantly predict mutational status. For example, AUC analysis results indicated that TP53, RB1, NF1, EGFR, and PDGFRA mutations could each be significantly predicted by at least one imaging feature. CONCLUSION: MRI-derived volumetric features are significantly associated with and predictive of several cancer-relevant, drug-targetable DNA mutations in glioblastoma. These results may shed insight into unique growth characteristics of individual tumors at the macroscopic level resulting from molecular events as well as increase the use of noninvasive imaging in personalized medicine.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Proteínas de Neoplasias/genética , Idoso , Neoplasias Encefálicas/epidemiologia , Feminino , Marcadores Genéticos/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Glioblastoma/epidemiologia , Humanos , Imageamento Tridimensional/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Estados Unidos/epidemiologia
13.
Neurobiol Dis ; 70: 224-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25014022

RESUMO

Charcot--Marie-Tooth disease type 1A (CMT1A) is a hereditary peripheral neuropathy characterized by progressive demyelination and distal muscle weakness. Abnormal expression of peripheral myelin protein 22 (PMP22) has been linked to CMT1A and is modeled by Trembler J (TrJ) mice, which carry the same leucine to proline substitution in PMP22 as affected pedigrees. Pharmacologic modulation of autophagy by rapamycin in neuron-Schwann cell explant cultures from neuropathic mice reduced PMP22 aggregate formation and improved myelination. Here we asked whether rapamycin administration by food supplementation, or intraperitoneal injection, could alleviate the neuropathic phenotype of affected mice and improve neuromuscular performance. Cohorts of male and female wild type (Wt) and TrJ mice were assigned to placebo or rapamycin treatment starting at 2 or 4months of age and tested monthly on the rotarod. While neither long-term feeding (8 or 10months) on rapamycin-enriched diet, or short-term injection (2months) of rapamycin improved locomotor performance of the neuropathic mice, both regimen benefited peripheral nerve myelination. Together, these results indicate that while treatment with rapamycin benefits the myelination capacity of neuropathic Schwann cells, this intervention does not improve neuromuscular function. The observed outcome might be the result of the differential response of nerve and skeletal muscle tissue to rapamycin.


Assuntos
Atividade Motora/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Células de Schwann/efeitos dos fármacos , Sirolimo/administração & dosagem , Animais , Doença de Charcot-Marie-Tooth , Estudos de Coortes , Suplementos Nutricionais , Feminino , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Mutação , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Bainha de Mielina/fisiologia , Neurônios/patologia , Neurônios/fisiologia , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Distribuição Aleatória , Teste de Desempenho do Rota-Rod , Células de Schwann/patologia , Células de Schwann/fisiologia , Técnicas de Cultura de Tecidos
14.
Purinergic Signal ; 10(4): 639-49, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25231507

RESUMO

The relative importance of ATP as a functional sympathetic neurotransmitter in blood vessels has been shown to be increased when the level of preexisting vascular tone or pressure is increased, in studies carried out in rat mesenteric arteries. The aim of the present study was to determine whether tone influences the involvement of ATP as a sympathetic cotransmitter with noradrenaline in another species. We used the porcine perfused mesenteric arterial bed and porcine mesenteric large, medium and small arteries mounted for isometric tension recording, because purinergic cotransmission can vary depending on the size of the blood vessel. In the perfused mesenteric bed at basal tone, sympathetic neurogenic vasocontractile responses were abolished by prazosin, an α1-adrenoceptor antagonist, but there was no significant effect of α,ß-methylene ATP, a P2X receptor-desensitizing agent. Submaximal precontraction of the mesenteric arterial bed with U46619, a thromboxane A2 mimetic, augmented the sympathetic neurogenic vasocontractile responses; under these conditions, both α,ß-methylene ATP and prazosin attenuated the neurogenic responses. In the mesenteric large, medium and small arteries, prazosin attenuated the sympathetic neurogenic contractile responses under conditions of both basal and U46619-raised tone. α,ß-Methylene ATP was effective in all of these arteries only under conditions of U46619-induced tone, causing a similar inhibition in all arteries, but had no significant effect on sympathetic neurogenic contractions at basal tone. These data show that ATP is a cotransmitter with noradrenaline in porcine mesenteric arteries; the purinergic component was revealed under conditions of partial precontraction, which is more relevant to physiological conditions.


Assuntos
Trifosfato de Adenosina/metabolismo , Artérias Mesentéricas/metabolismo , Músculo Liso Vascular/metabolismo , Neurotransmissores/metabolismo , Animais , Feminino , Masculino , Tono Muscular/fisiologia , Técnicas de Cultura de Órgãos , Suínos , Sistema Nervoso Simpático/fisiologia , Vasoconstrição/fisiologia
15.
Scott Med J ; 59(4): 182-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25246421

RESUMO

INTRODUCTION: The deep-fried Mars bar has been cited as 'all that is wrong with the high-fat, high-sugar Scottish diet'. We investigated the effect of ingestion of a deep-fried Mars bar or porridge on cerebrovascular reactivity. We hypothesised that deep-fried Mars bar ingestion would impair cerebrovascular reactivity, which is associated with increased risk of ischaemic stroke. METHODS: Twenty-four fasted volunteers were randomised to receive a deep-fried Mars bar and then porridge (control), or vice-versa. We used transcranial Doppler ultrasound to calculate Breath Holding Index as a surrogate measure of cerebrovascular reactivity. Change in Breath Holding Index post-ingestion was the primary outcome measure. RESULTS: Twenty-four healthy adults (mean (SD) age 21.5 (1.7) years, 14 males) completed the protocol. Deep-fried Mars bar ingestion caused a non-significant reduction in cerebrovascular reactivity relative to control (mean difference in absolute Breath Holding Index after deep-fried Mars bar versus porridge -0.11, p = 0.40). Comparison of the difference between the absolute change in Breath Holding Index between genders demonstrated a significant impairment of cerebrovascular reactivity in males (mean difference women minus men of 0.65, 95% CI 0.30 to 1.00, p = 0.0003). CONCLUSION: Ingestion of a bolus of sugar and fat caused no overall difference in cerebrovascular reactivity, but there was a modest decrease in males. Impaired cerebrovascular reactivity is associated with increased stroke risk, and therefore deep-fried Mars bar ingestion may acutely contribute to cerebral hypoperfusion in men.


Assuntos
Isquemia Encefálica/etiologia , Doces , Circulação Cerebrovascular , Culinária , Dieta Hiperlipídica , Grão Comestível , Acidente Vascular Cerebral/prevenção & controle , Adulto , Velocidade do Fluxo Sanguíneo , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/prevenção & controle , Doces/efeitos adversos , Estudos Cross-Over , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Masculino , Fatores de Risco , Escócia/epidemiologia , Fatores Sexuais , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Ultrassonografia Doppler Transcraniana
16.
Front Pharmacol ; 15: 1348172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344174

RESUMO

Introduction: One major obstacle in validating drugs for the treatment or prevention of hearing loss is the limited data available on the distribution and concentration of drugs in the human inner ear. Although small animal models offer some insights into inner ear pharmacokinetics, their smaller organ size and different barrier (round window membrane) permeabilities compared to humans can complicate study interpretation. Therefore, developing a reliable large animal model for inner ear drug delivery is crucial. The inner and middle ear anatomy of domestic pigs closely resembles that of humans, making them promising candidates for studying inner ear pharmacokinetics. However, unlike humans, the anatomical orientation and tortuosity of the porcine external ear canal frustrates local drug delivery to the inner ear. Methods: In this study, we developed a surgical technique to access the tympanic membrane of pigs. To assess hearing pre- and post-surgery, auditory brainstem responses to click and pure tones were measured. Additionally, we performed 3D segmentation of the porcine inner ear images and used this data to simulate the diffusion of dexamethasone within the inner ear through fluid simulation software (FluidSim). Results: We have successfully delivered dexamethasone and dexamethasone sodium phosphate to the porcine inner ear via the intratympanic injection. The recorded auditory brainstem measurements revealed no adverse effects on hearing thresholds attributable to the surgery. We have also simulated the diffusion rates for dexamethasone and dexamethasone sodium phosphate into the porcine inner ear and confirmed the accuracy of the simulations using in-vivo data. Discussion: We have developed and characterized a method for conducting pharmacokinetic studies of the inner ear using pigs. This animal model closely mirrors the size of the human cochlea and the thickness of its barriers. The diffusion time and drug concentrations we reported align closely with the limited data available from human studies. Therefore, we have demonstrated the potential of using pigs as a large animal model for studying inner ear pharmacokinetics.

17.
BMC Genomics ; 14: 739, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24168143

RESUMO

BACKGROUND: Dengue is the most prevalent arboviral disease world-wide and its primary vector is the mosquito Aedes aegypti. The current lack of commercially-available vaccines makes control of vector populations the only effective strategy to prevent dengue transmission. Aedes aegypti geographic populations exhibit great variability in insecticide resistance and susceptibility to dengue infection. The characterization of single nucleotide polymorphisms (SNPs) as molecular markers to study quantitatively this variation is needed greatly because this species has a low abundance of microsatellite markers and limited known restriction fragments length polymorphisms (RFLPs) and single-strand conformation polymorphism (SSCP) markers. RESULTS: We used RNA-seq to characterize SNPs in three Ae. aegypti strains, including the Liverpool (LVP) strain, from which the current genome annotation is derived. We identified 131,764 unique genome locations with at least one alternative nucleotide to what is reported in the reference annotation. These comprised changes in both open-reading frames (ORFs) and untranslated regions (UTRs) of transcripts. An in depth-look at sequence variation in immunity genes revealed that those associated with autophagy, MD2-like receptors and Peptidoglycan Recognition Proteins had more sequence variation in their 3'UTRs than mutations associated with non-synonymous changes. This supports the conclusion that these genes had maintained their functional specificity while being adapted to different regulatory domains. In contrast, a number of peroxidases, serpins and Clip-domain serine proteases exhibited conservation of putative UTR regulatory sequences while displaying diversification of the ORFs. Transcriptome evidence also was found for ~2500 novel transcriptional units (NTUs) not annotated in the reference genome. CONCLUSIONS: The transcriptome-wide assessment of within and inter-strain polymorphisms in Ae. aegypti adds considerably to the number of molecular markers available for genetic studies in this mosquito. Additionally, data supporting NTU discovery emphasizes the need for continuous amendments of the reference genome annotation.


Assuntos
Aedes/genética , Vírus da Dengue/fisiologia , Animais , Feminino , Biblioteca Gênica , Genoma , Insetos Vetores/metabolismo , Anotação de Sequência Molecular , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único , Análise de Sequência de RNA , Transcriptoma , Regiões não Traduzidas/genética
18.
Radiology ; 267(2): 560-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23392431

RESUMO

PURPOSE: To conduct a comprehensive analysis of radiologist-made assessments of glioblastoma (GBM) tumor size and composition by using a community-developed controlled terminology of magnetic resonance (MR) imaging visual features as they relate to genetic alterations, gene expression class, and patient survival. MATERIALS AND METHODS: Because all study patients had been previously deidentified by the Cancer Genome Atlas (TCGA), a publicly available data set that contains no linkage to patient identifiers and that is HIPAA compliant, no institutional review board approval was required. Presurgical MR images of 75 patients with GBM with genetic data in the TCGA portal were rated by three neuroradiologists for size, location, and tumor morphology by using a standardized feature set. Interrater agreements were analyzed by using the Krippendorff α statistic and intraclass correlation coefficient. Associations between survival, tumor size, and morphology were determined by using multivariate Cox regression models; associations between imaging features and genomics were studied by using the Fisher exact test. RESULTS: Interrater analysis showed significant agreement in terms of contrast material enhancement, nonenhancement, necrosis, edema, and size variables. Contrast-enhanced tumor volume and longest axis length of tumor were strongly associated with poor survival (respectively, hazard ratio: 8.84, P = .0253, and hazard ratio: 1.02, P = .00973), even after adjusting for Karnofsky performance score (P = .0208). Proneural class GBM had significantly lower levels of contrast enhancement (P = .02) than other subtypes, while mesenchymal GBM showed lower levels of nonenhanced tumor (P < .01). CONCLUSION: This analysis demonstrates a method for consistent image feature annotation capable of reproducibly characterizing brain tumors; this study shows that radiologists' estimations of macroscopic imaging features can be combined with genetic alterations and gene expression subtypes to provide deeper insight to the underlying biologic properties of GBM subsets.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Feminino , Expressão Gênica , Glioblastoma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Taxa de Sobrevida , Terminologia como Assunto
19.
Subcell Biochem ; 57: 161-86, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22094422

RESUMO

Understanding how non-dividing cells remain viable over long periods of time, which may be decades in humans, is of central importance in understanding mechanisms of aging and longevity. The long-term viability of non-dividing cells, known as chronological longevity, relies on cellular processes that degrade old components and replace them with new ones. Key among these processes is amino acid homeostasis. Amino acid homeostasis requires three principal functions: amino acid uptake, de novo synthesis, and recycling. Autophagy plays a key role in recycling amino acids and other metabolic building blocks, while at the same time removing damaged cellular components such as mitochondria and other organelles. Regulation of amino acid homeostasis and autophagy is accomplished by a complex web of pathways that interact because of the functional overlap at the level of recycling. It is becoming increasingly clear that amino acid homeostasis and autophagy play important roles in chronological longevity in yeast and higher organisms. Our goal in this chapter is to focus on mechanisms and pathways that link amino acid homeostasis, autophagy, and chronological longevity in yeast, and explore their relevance to aging and longevity in higher eukaryotes.


Assuntos
Envelhecimento/metabolismo , Aminoácidos/metabolismo , Metabolismo Energético , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Adaptação Fisiológica , Envelhecimento/genética , Autofagia , Restrição Calórica , Divisão Celular , Regulação Fúngica da Expressão Gênica , Homeostase , Longevidade , Viabilidade Microbiana , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Tempo
20.
Healthcare (Basel) ; 11(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38063621

RESUMO

BACKGROUND: Rape scholarship in West Africa is growing, but studies often utilize Westernized approaches. A 2018 study using a randomized survey design assessing rape among Liberian girls incorporated modified survey design methods to improve ethical data collection relevant to the cultural and contextual contexts. This article presents the findings of a thorough review of rape scholarship and design methods. METHODS: Based on a qualitative analysis of field notes by the research team, we present lessons learned and best practices identified in the planning, pilot-testing, and implementation phases of the 2018 Liberian study. RESULTS: This study helps inform innovative design methods striving to (1) avoid using obtrusively graphic language or labels prevalent in westernized studies, (2) authentically collaborate with African experts to adapt strategies to be culturally appropriate and contextually relevant, and (3) create respectfully transparent interactions with respondents and communities. Extensive research preparation and inclusive regional expertise inform compassionate methodological techniques, yielding improved Afro-centric participant experience, low participant attrition, and quality data use in policymaking. (4) Conclusions: This article offers innovative design methods to study rape, placing context, culture, and participants at the heart. Authentic collaboration with national-level experts is vital for conducting more reliable and ethical field research in the African region.

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