Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Genes Chromosomes Cancer ; 59(2): 84-95, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31407403

RESUMO

Cervical carcinogenesis, the second leading cause of cancer death in women worldwide, is caused by multiple types of human papillomaviruses (HPVs). To investigate a possible role for HPV in a cervical carcinoma that was HPV-negative by PCR testing, we performed HPV DNA hybridization capture plus massively parallel sequencing. This detected a subgenomic, URR-E6-E7-E1 segment of HPV70 DNA, a type not generally associated with cervical cancer, inserted in an intron of the B-cell lymphoma/leukemia 11B (BCL11B) gene in the human genome. Long range DNA sequencing confirmed the virus and flanking BCL11B DNA structures including both insertion junctions. Global transcriptomic analysis detected multiple, alternatively spliced, HPV70-BCL11B, fusion transcripts with fused open reading frames. The insertion and fusion transcripts were present in an intraepithelial precursor phase of tumorigenesis. These results suggest oncogenicity of HPV70, identify novel BCL11B variants with potential oncogenic implications, and underscore the advantages of thorough genomic analyses to elucidate insights into HPV-associated tumorigenesis.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/genética , Sequência de Bases , Carcinogênese/genética , Carcinogênese/metabolismo , DNA Viral/análise , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pessoa de Meia-Idade , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/metabolismo
2.
Sci Total Environ ; 814: 152546, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34973322

RESUMO

The complex biogeochemical behavior of iodine (I) isotopes and their interaction with natural organic matter (NOM) pose a challenge for transport models. Here, we present results from iodination experiments with humic acid (HA) and fulvic acid (FA) using 1H-13C heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) spectroscopy. Even though not a quantitative approach, 1H-13C HSQC NMR corroborated that iodination of NOM occurs primarily through aromatic electrophilic substitution of proton by I, and also revealed how iodination chemically alters HA and FA in a manner that potentially affects the mobility of iodinated NOM in the environment. Three types of iodination experiments were conducted with HA and FA: a) non-enzymatic iodination by IO3- (pH 3) and I- (pH 4 and 7), b) addition of lactoperoxidase to promote I--iodination in the presence of the co-substrate, H2O2 (pH 7), and c) addition of laccase for facilitating I--iodination in the presence of O2, with or without a mediator (pH 4). When mediators or H2O2 were present, extracellular oxidases and peroxidases enhanced I- incorporation into NOM by between 54% and 3400%. Iodination of HA, which was less than that of FA, enhanced HA's stability (inferred from increases in aliphatic compounds, decreases in carbohydrate moieties, and thus increased molecular hydrophobicity) yet reduced HA's tendency to incorporate more iodine. As such, HA is expected to act more as a sink for iodine in the environment. In contrast, iodination of FA appeared to generate additional iodine binding sites, which resulted in greater iodine uptake capability and enhanced mobility (inferred from decreases in aliphatic compounds, increases in carbohydrates, and thus decreases in molecular hydrophobicity). These results indicate that certain NOM moieties may enhance while others may inhibit radioiodine mobility in the aqueous environment.


Assuntos
Iodo , Halogenação , Substâncias Húmicas , Peróxido de Hidrogênio , Radioisótopos do Iodo , Prótons
3.
Appl Environ Microbiol ; 76(13): 4469-75, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20472727

RESUMO

Coxiella burnetii is an obligate intracellular bacterium that causes the zoonotic disease Q fever. Because C. burnetii is highly infectious, can survive under a variety of environmental conditions, and has been weaponized in the past, it is classified as a select agent and is considered a potential bioweapon. The agent is known to be present in domestic livestock and in wild animal populations, but the background levels of C. burnetii in the environment have not been reported. To better understand the amount of C. burnetii present in the environment of the United States, more than 1,600 environmental samples were collected from six geographically diverse parts of the United States in the years 2006 to 2008. DNA was purified from these samples, and the presence of C. burnetii DNA was evaluated by quantitative PCR of the IS1111 repetitive element. Overall, 23.8% of the samples were positive for C. burnetii DNA. The prevalence in the different states ranged from 6 to 44%. C. burnetii DNA was detected in locations with livestock and also in locations with primarily human activity (post offices, stores, schools, etc.). This study demonstrates that C. burnetii is fairly common in the environment in the United States, and any analysis of C. burnetii after a suspected intentional release should be interpreted in light of these background levels. It also suggests that human exposure to C. burnetii may be more common than what is suggested by the number of reported cases of Q fever.


Assuntos
Coxiella burnetii/genética , Coxiella burnetii/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Microbiologia Ambiental , Reação em Cadeia da Polimerase/métodos , Animais , Elementos de DNA Transponíveis/genética , Humanos , Camundongos , Prevalência , Estados Unidos/epidemiologia
4.
BMC Med Genomics ; 13(1): 179, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256706

RESUMO

BACKGROUND: The Cancer Genome Atlas identified four molecular subgroups of endometrial cancer with survival differences based on whole genome, transcriptomic, and proteomic characterization. Clinically accessible algorithms that reproduce this data are needed. Our aim was to determine if targeted sequencing alone allowed for molecular classification of endometrial cancer. METHODS: Using a custom-designed 156 gene panel, we analyzed 47 endometrial cancers and matching non-tumor tissue. Variants were annotated for pathogenicity and medical records were reviewed for the clinicopathologic variables. Using molecular characteristics, tumors were classified into four subgroups. Group 1 included patients with > 570 unfiltered somatic variants, > 9 cytosine to adenine nucleotide substitutions per sample, and < 1 cytosine to guanine nucleotide substitution per sample. Group 2 included patients with any somatic mutation in MSH2, MSH6, MLH1, PMS2. Group 3 included patients with TP53 mutations without mutation in mismatch repair genes. Remaining patients were classified as group 4. Analyses were performed using SAS 9.4 (SAS Institute Inc., Cary, North Carolina, USA). RESULTS: Endometrioid endometrial cancers had more candidate variants of potential pathogenic interest (median 6 IQR 4.13 vs. 2 IQR 2.3; p < 0.01) than uterine serous cancers. PTEN (82% vs. 15%, p < 0.01) and PIK3CA (74% vs. 23%, p < 0.01) mutations were more frequent in endometrioid than serous carcinomas. TP53 (18% vs. 77%, p < 0.01) mutations were more frequent in serous carcinomas. Visual inspection of the number of unfiltered somatic variants per sample identified six grade 3 endometrioid samples with high tumor mutational burden, all of which demonstrated POLE mutations, most commonly P286R and V411L. Of the grade 3 endometrioid carcinomas, those with POLE mutations were less likely to have risk factors necessitating adjuvant treatment than those with low tumor mutational burden. Targeted sequencing was unable to assign samples to microsatellite unstable, copy number low, and copy number high subgroups. CONCLUSIONS: Targeted sequencing can predict the presence of POLE mutations based on the tumor mutational burden. However, targeted sequencing alone is inadequate to classify endometrial cancers into molecular subgroups identified by The Cancer Genome Atlas.


Assuntos
DNA de Neoplasias/genética , Neoplasias do Endométrio/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Proteínas de Neoplasias/genética , Idoso , Carcinoma Endometrioide/genética , Variações do Número de Cópias de DNA , Reparo de Erro de Pareamento de DNA/genética , DNA Polimerase II/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/terapia , Feminino , Humanos , Mutação INDEL , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Segunda Neoplasia Primária/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Polimorfismo de Nucleotídeo Único
5.
Clin Infect Dis ; 48(5): 550-7, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19191638

RESUMO

BACKGROUND: Little is known about the occurrence of Q fever among veterinarians in the United States. In this study, we sought to estimate the prevalence of Coxiella burnetii antibodies among veterinarians and to identify risk factors for exposure. METHODS: We tested serum samples from 508 veterinarians who attended the 143rd American Veterinary Medical Association Annual Convention in 2006. Samples were screened using a Q fever IgG enzyme-linked immunosorbent assay (ELISA). Samples with positive or equivocal results of ELISA were confirmed using phase I and phase II IgG immunofluorescence antibody assays, and end point IgG titers were determined for samples with positive results. RESULTS: Antibodies against C. burnetii were detected in 113 (22.2%) of 508 veterinarians. Risk factors associated with seropositivity included age 46 years, routine contact with ponds, and treatment of cattle, swine, or wildlife. CONCLUSIONS: Veterinarians have a high level of exposure to C. burnetii, the causative organism of Q fever, especially those veterinarians who treat livestock. In this study, risk of C. burnetii seropositivity was also independently associated with contact with ponds. The role of exposure to standing bodies of water in infection is not usually considered and should be investigated in future studies. Additionally, the evidence of past infection with C. burnetii in >20% of veterinarians also highlights the need for use of appropriate personal protective equipment when treating animals that are potentially infected with C. burnetii. Physicians should consider the risk of infection with C. burnetii when treating ill veterinarians and others with potential occupational exposures.


Assuntos
Anticorpos Antibacterianos/sangue , Coxiella burnetii/isolamento & purificação , Doenças Profissionais/epidemiologia , Febre Q/epidemiologia , Médicos Veterinários , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Animais Domésticos , Animais Selvagens , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia
6.
Sci Signal ; 12(585)2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186373

RESUMO

AMP-activated protein kinase (AMPK) senses energetic stress and, in turn, promotes catabolic and suppresses anabolic metabolism coordinately to restore energy balance. We found that a diverse array of AMPK activators increased mTOR complex 2 (mTORC2) signaling in an AMPK-dependent manner in cultured cells. Activation of AMPK with the type 2 diabetes drug metformin (GlucoPhage) also increased mTORC2 signaling in liver in vivo and in primary hepatocytes in an AMPK-dependent manner. AMPK-mediated activation of mTORC2 did not result from AMPK-mediated suppression of mTORC1 and thus reduced negative feedback on PI3K flux. Rather, AMPK associated with and directly phosphorylated mTORC2 (mTOR in complex with rictor). As determined by two-stage in vitro kinase assay, phosphorylation of mTORC2 by recombinant AMPK was sufficient to increase mTORC2 catalytic activity toward Akt. Hence, AMPK phosphorylated mTORC2 components directly to increase mTORC2 activity and downstream signaling. Functionally, inactivation of AMPK, mTORC2, and Akt increased apoptosis during acute energetic stress. By showing that AMPK activates mTORC2 to increase cell survival, these data provide a potential mechanism for how AMPK paradoxically promotes tumorigenesis in certain contexts despite its tumor-suppressive function through inhibition of growth-promoting mTORC1. Collectively, these data unveil mTORC2 as a target of AMPK and the AMPK-mTORC2 axis as a promoter of cell survival during energetic stress.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Metabolismo Energético , Hepatócitos/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Estresse Fisiológico , Proteínas Quinases Ativadas por AMP/genética , Animais , Linhagem Celular , Sobrevivência Celular , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
Oncotarget ; 8(60): 102033-102045, 2017 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-29254223

RESUMO

Next generation sequencing (NGS) technologies have revolutionized our approach to genomic research. The use of whole genome sequencing (WGS), whole exome sequencing (WES), transcriptome profiling, and targeted DNA sequencing has exponentially improved our understanding of the human genome and the genetic complexities underlying malignancy. Yet, WGS and WES clinical applications remain limited due to high costs and the large volume of data generated. When utilized to address biological questions in basic science studies, targeted sequencing panels have proven extremely valuable due to reduced costs and higher sequencing depth. However, the routine application of targeted sequencing to the clinical setting is limited to a few cancer subtypes. Some highly aggressive tumor types, like type 2 endometrial cancer (EC), could greatly benefit from routine genomic analysis using targeted sequencing. To explore the potential utility of a mid size panel (~150 genes) in the clinical setting, we developed and validated a custom panel against WGS, WES, and another commercially available targeted panel. Our results indicate that a mid size custom designed panel is as efficient as WGS and WES in mapping variants of biological and clinical relevance, rendering higher coverage, at a lower cost, with fewer variants of uncertain significance. Because of the much higher sequencing depth that could be achieved, our results demonstrate that targeted sequencing outperformed WGS and WES in the mapping of pathogenic variants in a breast cancer case, as well as a case of mixed serous and high-grade endometrioid EC, the most aggressive EC subtype.

8.
Expert Rev Precis Med Drug Dev ; 1(3): 331-343, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27622214

RESUMO

New technologies are rapidly becoming available to expand the arsenal of tools accessible for precision medicine and to support the development of new therapeutics. Advances in liquid biopsies, which analyze cells, DNA, RNA, proteins, or vesicles isolated from the blood, have gained particular interest for their uses in acquiring information reflecting the biology of tumors and metastatic tissues. Through advancements in DNA sequencing that have merged unprecedented accuracy with affordable cost, personalized treatments based on genetic variations are becoming a real possibility. Extraordinary progress has been achieved in the development of biological therapies aimed to even further advance personalized treatments. We provide a summary of current and future applications of blood based liquid biopsies and how new technologies are utilized for the development of biological therapeutic treatments. We discuss current and future sequencing methods with an emphasis on how technological advances will support the progress in the field of precision medicine.

9.
Clin Epigenetics ; 8: 67, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293492

RESUMO

BACKGROUND: Preeclampsia, traditionally characterized by high blood pressure and proteinuria, is a common pregnancy complication, which affects 2-8 % of all pregnancies. Although children born to women with preeclampsia have a higher risk of hypertension in later life, the mechanism of this increased risk is unknown. DNA methylation is an epigenetic modification that has been studied as a mediator of cellular memory of adverse exposures in utero. Since each cell type in the body has a unique DNA profile, cell subtype composition is a major confounding factor in studies of tissues with heterogeneous cell types. The best way to avoid this confounding effect is by using purified cell types. However, using purified cell types in large cohort translational studies is difficult. The amnion, the inner layer of the fetal membranes of the placenta, is derived from the epiblast and consists of two cell types, which are easy to isolate from the delivered placenta. In this study, we demonstrate the value of using amnion samples for DNA methylation studies, revealing distinctive patterns between fetuses exposed to proteinuria or hypertension and fetuses from normal pregnancies. RESULTS: We performed a genome-wide DNA methylation analysis, HpaII tiny fragment Enrichment by Ligation-mediated PCR (HELP)-tagging, on 62 amnion samples from the placentas of uncomplicated, normal pregnancies and from those with complications of preeclampsia or hypertension. Using a regression model approach, we found 123, 85, and 99 loci with high-confidence hypertension-associated, proteinuria-associated, and hypertension- and proteinuria-associated DNA methylation changes, respectively. A gene ontology analysis showed DNA methylation changes to be selecting genes with different biological processes in exposure status. We also found that these differentially methylated regions overlap loci previously reported as differentially methylated regions in preeclampsia. CONCLUSIONS: Our findings support prior observations that preeclampsia is associated with changes of DNA methylation near genes that have previously been found to be dysregulated in preeclampsia. We propose that amniotic membranes represent a valuable surrogate fetal tissue on which to perform epigenome-wide association studies of adverse intrauterine conditions.


Assuntos
Âmnio/metabolismo , Metilação de DNA , Hipertensão/genética , Pré-Eclâmpsia/genética , Efeitos Tardios da Exposição Pré-Natal/genética , Ilhas de CpG , Epigênese Genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Gravidez , Regiões Promotoras Genéticas , Análise de Regressão
10.
Am J Trop Med Hyg ; 81(4): 691-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19815888

RESUMO

We performed serum testing for IgG antibodies against Coxiella burnetii (phase I and phase II) and analyzed questionnaire data from 4,437 adults > or = 20 years of age who participated in the National Health and Nutrition Examination Survey 2003-2004 survey cycle. National Q fever seroprevalence was determined by enzyme-linked immunosorbent assay and confirmed by using immunofluorescent antibody testing. Overall seroprevalence for Coxiella burnetii was 3.1% (95% confidence interval [CI] = 2.1-4.3%) among 4,437 adults > or = 20 years of age. Coxiella burnetii age-adjusted antibody prevalence was higher for men than for women (3.8%, 95% CI = 2.7-5.2% versus 2.5%, 95% CI = 1.5-3.7%, respectively, P < 0.05). Mexican Americans had a significantly higher antibody prevalence (7.4%, 95% CI = 6.6-8.3%) than either non-Hispanic whites (2.8%, 95% CI = 1.7-4.3%) or non-Hispanic blacks (1.3%, 95% CI = 0.6-2.5%) (P < 0.001). Multivariate analysis showed that the risk for Q fever antibody positivity increased with age and was higher among persons who were foreign-born, male, and living in poverty. These findings indicate that the national seroprevalence of Q fever in the United States is higher than expected on the basis of case numbers reported to the Centers for Disease Control and Prevention from state health departments. Potential differences in risk for exposure by race/ethnicity warrant further study.


Assuntos
Febre Q/epidemiologia , Adulto , Idoso , Animais , Anticorpos Antibacterianos/sangue , Coxiella burnetii/imunologia , Emigrantes e Imigrantes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Fatores Socioeconômicos , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa