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1.
Rev Environ Contam Toxicol ; 251: 131-184, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31129734

RESUMO

Maternal exposure to endocrine-disrupting chemicals (EDCs) is associated with long-term hormone-dependent effects that are sometimes not revealed until maturity, middle age, or adulthood. The aim of this study was to conduct descriptive reviews on animal experimental and human epidemiological evidence of the adverse health effects of in utero and lactational exposure to selected EDCs on the first generation and subsequent generation of the exposed offspring. PubMed, Web of Science, and Toxline databases were searched for relevant human and experimental animal studies on 29 October 29 2018. Search results were screened for relevance, and studies that met the inclusion criteria were evaluated and qualitative data extracted for analysis. The search yielded 73 relevant human and 113 animal studies. Results from studies show that in utero and lactational exposure to EDCs is associated with impairment of reproductive, immunologic, metabolic, neurobehavioral, and growth physiology of the exposed offspring up to the fourth generation without additional exposure. Little convergence is seen between animal experiments and human studies in terms of the reported adverse health effects which might be associated with methodologic challenges across the studies. Based on the available animal and human evidence, in utero and lactational exposure to EDCs is detrimental to the offspring. However, more human studies are necessary to clarify the toxicological and pathophysiological mechanisms underlying these effects.


Assuntos
Disruptores Endócrinos , Exposição Materna/estatística & dados numéricos , Animais , Feminino , Humanos , Gravidez
2.
Biol Reprod ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621835

RESUMO

Anti-androgenic endocrine-disrupting chemicals (EDCs) can cross the placenta to modify early offspring sexual dimorphic markers. These changes are linked to Anogenital Distance (AGD), which is an androgen sensitive anthropometric parameter used as a biomarker of perineal growth and caudal migration of the genital tubercle. This review aimed to summarize strength of evidence for associations of in utero exposure to EDCs with AGD and to identify gaps and limitations in the literature so as to inform future research. We performed an electronic search of English literature through September 2019 in MEDLINE, Web of Science and Toxline. We included epidemiological studies that examined in utero exposure to persistent and non-persistent EDCs, and considered AGD in offspring as an outcome. Our review contained 16 investigations examining exposure to persistent EDCs (9 studies) and non-persistent EDCs (7 studies). Some individual studies reported an inverse association between exposure to BPA, dioxins, perfluoroalkyl substances and organochlorides, and AGD in both male and female offspring. Meta-analysis of 3 studies found a small reduction of AGD in female offspring exposed to BPA. The number of studies per chemical is small and number of subjects examined is limited; so, replication of these results is needed. To achieve more specificity and better replication of results, future studies should establish the association of non-persistent EDCs using multiple urine samples, evaluate the cumulative impact of exposure to a mixture of anti-androgenic chemicals, and offer adequate consideration of more maternal- and children-related confounding factors.

3.
J Vis Exp ; (152)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31657800

RESUMO

Differential gene expression analysis is an important technique for understanding disease states. The machine learning algorithm CorEx has shown utility in analyzing differential expression of groups of genes in tumor RNA-seq in a way that may be helpful for advancing precision oncology. However, CorEx produces many factors that can be challenging to analyze and connect to existing understanding. To facilitate such connections, we have built a website, CorExplorer, that allows users to interactively explore the data and answer common questions related to its analysis. We trained CorEx on RNA-seq gene expression data for four tumor types: ovarian, lung, melanoma, and colorectal. We then incorporated corresponding survival, protein-protein interactions, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichments, and heatmaps into the website for association with the factor graph visualization. Here we employ example protocols to illustrate use of the database for comprehending the significance of the learned tumor factors in the context of this external data.

4.
J Cardiovasc Electrophysiol ; 30(11): 2484-2491, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31535773

RESUMO

INTRODUCTION: Noise oversensing encountered in patients with Abbott Tendril leads in our hospital triggered an internal investigation. METHODS: We retrospectively analyzed patients with a Tendril lead model 1688, 1788, 1888, and 2088. Most leads were connected to Abbott generators. To exclude a primary generator issue as the cause of noise oversensing, we enrolled a cohort of patients in whom Medtronic CapSureFix leads model 4076 and 5076 were prospectively connected to similar Abbott generators. RESULTS: A total of 1063 Tendril leads were implanted in 869 patients. Noise was encountered in 66 leads (6.2%) during a follow-up of 3.9 years. Most affected leads had normal impedance and only a few of these patients were symptomatic. Reprogramming was attempted in 44 of 66 (67%), and reduced oversensing in 34 of 44 (77%) of these patients. Seventeen malfunctioning leads (1.5%) were replaced, including 16 of 66 (24%) of those with noise. Of the four leads with noise extracted and returned to the manufacturer, lead to device abrasion was identified in two and inner insulation breach in one. None of the 145 Medtronic CapSureFix leads connected to Abbott generators had noise during a follow-up of 3.6 years. CONCLUSION: Noise oversensing was relatively common in Tendril leads, but was not detected in Medtronic leads despite connecting to Abbott generators. Although the majority of the affected leads did not show abnormal impedance, outer or inner insulation breach was identified in three of the four returned leads. As patients with affected leads are generally asymptomatic, most of them can be managed conservatively.

5.
Prostate ; 79(14): 1622-1628, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31376187

RESUMO

BACKGROUND: The protist Trichomonas vaginalis causes a common, sexually transmitted infection and has been proposed to contribute to the development of chronic prostate conditions, including benign prostatic hyperplasia and prostate cancer. However, few studies have investigated the extent to which it involves the prostate in the current antimicrobial era. We addressed this question by investigating the relation between T. vaginalis antibody serostatus and serum prostate-specific antigen (PSA) concentration, a marker of prostate infection, inflammation, and/or cell damage, in young, male, US military members. METHODS: We measured T. vaginalis serum IgG antibodies and serum total PSA concentration in a random sample of 732 young, male US active duty military members. Associations between T. vaginalis serostatus and PSA were investigated by linear regression. RESULTS: Of the 732 participants, 341 (46.6%) had a low T. vaginalis seropositive score and 198 (27.0%) had a high score, with the remainder seronegative. No significant differences were observed in the distribution of PSA by T. vaginalis serostatus. However, slightly greater, nonsignificant differences were observed when men with high T. vaginalis seropositive scores were compared with seronegative men, and when higher PSA concentrations were examined (≥0.70 ng/mL). Specifically, 42.5% of men with high seropositive scores had a PSA concentration greater than or equal to 0.70 ng/mL compared with 33.2% of seronegative men (adjusted P = .125). CONCLUSIONS: Overall, our findings do not provide strong support for prostate involvement during T. vaginalis infection, although our suggestive positive findings for higher PSA concentrations do not rule out this possibility entirely. These suggestive findings may be relevant for prostate condition development because higher early- to mid-life PSA concentrations have been found to predict greater prostate cancer risk later in life.

6.
Cancer Epidemiol Biomarkers Prev ; 28(8): 1331-1338, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31160348

RESUMO

BACKGROUND: To evaluate the association of liver fibrosis scores with PSA level among U.S. adult men overall and by race/ethnicity. METHODS: Data from the National Health and Nutrition Examination Survey (NHANES), 2001-2010, were used. Males ages ≥40 years without a prostate cancer diagnosis and who had serum PSA, liver enzymes, albumin, and platelet counts measured as part of NHANES protocol were included. Liver fibrosis was measured using three scores: aspartate aminotransferase to platelet ratio index (APRI), fibrosis 4 index (FIB-4), and NAFLD fibrosis score (NFS). We assessed overall and race/ethnicity-stratified geometric mean PSA by fibrosis score using predictive margins by linear regression, and the association of abnormal fibrosis scores (APRI > 1, FIB-4 > 2.67, NFS > 0.676) and elevated PSA (>4 ng/mL) by logistic regression. RESULTS: A total of 6,705 men were included. Abnormal liver fibrosis scores were present in 2.1% (APRI), 3.6% (FIB-4), and 5.6% (NFS). Men with higher fibrosis scores had lower geometric mean PSA (all P trend < 0.02). Men with abnormal APRI had a lower odds of PSA > 4 ng/mL [adjusted OR (aOR) = 0.33; 95% confidence interval (CI), 0.11-0.96]. Compared with men with 0 abnormal scores, those with 2 or 3 abnormal fibrosis scores had a lower odds of PSA > 4 ng/mL (aOR = 0.55; 95% CI, 0.33-0.91). The patterns were similar by race/ethnicity. CONCLUSIONS: Men of all race/ethnicities with higher liver fibrosis scores had lower serum PSA, and men with advanced fibrosis scores had a lower odds of an elevated PSA. IMPACT: These findings support further research to inform the likelihood of delay in prostate cancer detection in men with abnormal liver function.

8.
Transbound Emerg Dis ; 66(2): 908-914, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30554469

RESUMO

African swine fever (ASF) is a devastating disease of pigs. Without a vaccine, early detection and rapid diagnosis of ASF is a crucial step towards effective disease control. In many countries where ASF is endemic, laboratory infrastructure including sampling and sample shipment is inadequate, and a rapid laboratory confirmation would require that the diagnosis is performed at regional laboratories close to the pig farms of concern, or even at the farm-side. This study intended to evaluate measures including sample preparation methods, a dried-down assay, and a portable, battery-powered real-time PCR instrument, to improve molecular diagnosis under field conditions. A simple dilution of blood samples, either in Phosphate-buffered saline or a commercial buffer, worked similarly to beads-based nucleic acid extraction using a magnet as the core equipment; the latter method did work as well for those samples with low viral load or high Ct values. The real-time PCR assay using a Universal ProbeLibrary (UPL) probe tolerated suspected inhibitory substances present in the prepared samples better, whereas the dried-down assay had a higher diagnostic sensitivity. Additionally, an inhibition control assay proved to be helpful in avoiding false negative results when interpreting negative results of samples that might be of low quality or with inadequate reduction in inhibitory substances. When tested with synthetic DNA standards, the portable instrument performed at a level approaching stationary thermocyclers. In summary, the developments of suitable sample preparation methods, robust and thermal-stable real-time PCR assays with inhibition control, and battery-powered portable thermocyclers with middle-throughput offer one way forward to provide rapid, reliable molecular diagnosis under challenging field conditions.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/diagnóstico , Surtos de Doenças/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Febre Suína Africana/virologia , Animais , DNA Viral/genética , Suínos
9.
Elife ; 72018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30427775

RESUMO

Shear forces between cells occur during global changes in multicellular organization during morphogenesis and tissue growth, yet how cells sense shear forces and propagate a response across a tissue is unknown. We found that applying exogenous shear at the midline of an epithelium induced a local, short-term deformation near the shear plane, and a long-term collective oscillatory movement across the epithelium that spread from the shear-plane and gradually dampened. Inhibiting actomyosin contraction or E-cadherin trans-cell adhesion blocked oscillations, whereas stabilizing actin filaments prolonged oscillations. Combining these data with a model of epithelium mechanics supports a mechanism involving the generation of a shear-induced mechanical event at the shear plane which is then relayed across the epithelium by actomyosin contraction linked through E-cadherin. This causes an imbalance of forces in the epithelium, which is gradually dissipated through oscillatory cell movements and actin filament turnover to restore the force balance across the epithelium.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30482876

RESUMO

BACKGROUND: Given the recent findings from pooled studies about a potential inverse association between selenium levels and prostate cancer risk, the current cross-sectional study aimed to investigate the association between serum selenium and serum concentrations of sex steroid hormones including estradiol in a nationally representative sample of US men to investigate one mechanism by which selenium may influence prostate cancer risk. METHODS: The study included 1,420 men aged 20 years or older who participated in the Third National Health and Nutrition Examination Survey (NHANES III) between 1988 and 1994. We calculated age/race-ethnicity-adjusted and multivariable-adjusted geometric mean serum concentrations of total and estimated free testosterone and estradiol, androstanediol glucuronide (AAG), and sex hormone binding globulin (SHBG) and compared them across quartiles of serum selenium. RESULTS: Adjusting for age, race/ethnicity, smoking status, serum cotinine, household income, physical activity, alcohol consumption and percent body fat, mean total estradiol (e.g. Q1:38.00 pg/mL (95%CI:36.03-40.08) vs Q4:35.29 pg/mL (33.53-37.14); Ptrend=0.050)and free estradiol [e.g.Q1: 0.96 pg/mL (95%CI: 0.92-1.01) vs Q4: 0.90 (95%CI:0.85-0.95); Ptrend=0.065] concentrations decreased over quartiles of selenium. Stratification by smoking and alcohol consumption, showed that the latter observation was stronger for never smokers (Pinteraction=0.073) and those with limited alcohol intake (Pinteraction=0.017). No associations were observed for the other sex steroid hormones studied. CONCLUSION: Our findings suggests that a possible mechanism by which selenium may be protective for prostate cancer is related to estrogen. IMPACT: Further studies of longitudinal measurements of serum and toenail selenium in relation to serum measurements of sex steroid hormones are needed.

11.
MBio ; 9(5)2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30352934

RESUMO

Posttranslational modifications, such as Nε-lysine acetylation, regulate protein function. Nε-lysine acetylation can occur either nonenzymatically or enzymatically. The nonenzymatic mechanism uses acetyl phosphate (AcP) or acetyl coenzyme A (AcCoA) as acetyl donor to modify an Nε-lysine residue of a protein. The enzymatic mechanism uses Nε-lysine acetyltransferases (KATs) to specifically transfer an acetyl group from AcCoA to Nε-lysine residues on proteins. To date, only one KAT (YfiQ, also known as Pka and PatZ) has been identified in Escherichia coli Here, we demonstrate the existence of 4 additional E. coli KATs: RimI, YiaC, YjaB, and PhnO. In a genetic background devoid of all known acetylation mechanisms (most notably AcP and YfiQ) and one deacetylase (CobB), overexpression of these putative KATs elicited unique patterns of protein acetylation. We mutated key active site residues and found that most of them eliminated enzymatic acetylation activity. We used mass spectrometry to identify and quantify the specificity of YfiQ and the four novel KATs. Surprisingly, our analysis revealed a high degree of substrate specificity. The overlap between KAT-dependent and AcP-dependent acetylation was extremely limited, supporting the hypothesis that these two acetylation mechanisms play distinct roles in the posttranslational modification of bacterial proteins. We further showed that these novel KATs are conserved across broad swaths of bacterial phylogeny. Finally, we determined that one of the novel KATs (YiaC) and the known KAT (YfiQ) can negatively regulate bacterial migration. Together, these results emphasize distinct and specific nonenzymatic and enzymatic protein acetylation mechanisms present in bacteria.IMPORTANCE Nε-Lysine acetylation is one of the most abundant and important posttranslational modifications across all domains of life. One of the best-studied effects of acetylation occurs in eukaryotes, where acetylation of histone tails activates gene transcription. Although bacteria do not have true histones, Nε-lysine acetylation is prevalent; however, the role of these modifications is mostly unknown. We constructed an E. coli strain that lacked both known acetylation mechanisms to identify four new Nε-lysine acetyltransferases (RimI, YiaC, YjaB, and PhnO). We used mass spectrometry to determine the substrate specificity of these acetyltransferases. Structural analysis of selected substrate proteins revealed site-specific preferences for enzymatic acetylation that had little overlap with the preferences of the previously reported acetyl-phosphate nonenzymatic acetylation mechanism. Finally, YiaC and YfiQ appear to regulate flagellum-based motility, a phenotype critical for pathogenesis of many organisms. These acetyltransferases are highly conserved and reveal deeper and more complex roles for bacterial posttranslational modification.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30082453

RESUMO

A better understanding of the early stages of prostate cancer initiation, potentially arising from precursor lesions, may fuel development of powerful approaches for prostate cancer prevention or interception. The best-known candidate for such a precursor lesion has been referred to as high-grade prostatic intraepithelial neoplasia (HGPIN). Although there is significant evidence supporting the notion that such HGPIN lesions can give rise to invasive adenocarcinomas of the prostate, there are also numerous complicating considerations and evidence that cloud the picture in many instances. Notably, recent evidence has suggested that some fraction of such lesions that are morphologically consistent with HGPIN may actually be invasive carcinomas masquerading as HGPIN-a state that we term "postinvasive intraepithelial carcinoma" (PIC). Although the prevalence of such PIC lesions is not fully understood, this and other factors can confound the potential of identifying prostate precursors that can be targeted for disease prevention, interception, or treatment. Here, we review our current understanding of the morphological and molecular pathological features of prostate cancer precursor lesions.

15.
Evol Med Public Health ; 2018(1): 127-137, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30087774

RESUMO

Background and objectives: The rate of evolution of drug resistance depends on the fitness of resistant pathogens. The fitness of resistant pathogens is reduced by competition with sensitive pathogens in untreated hosts and so enhanced by competitive release in drug-treated hosts. We set out to estimate the magnitude of those effects on a variety of fitness measures, hypothesizing that competitive suppression and competitive release would have larger impacts when resistance was rarer to begin with. Methodology: We infected mice with varying densities of drug-resistant Plasmodium chabaudi malaria parasites in a fixed density of drug-sensitive parasites and followed infection dynamics using strain-specific quantitative PCR. Results: Competition with susceptible parasites reduced the absolute fitness of resistant parasites by 50-100%. Drug treatment increased the absolute fitness from 2- to >10 000-fold. The ecological context and choice of fitness measure was responsible for the wide variation in those estimates. Initial population growth rates poorly predicted parasite abundance and transmission probabilities. Conclusions and implications: (i) The sensitivity of estimates of pathogen fitness to ecological context and choice of fitness measure make it difficult to derive field-relevant estimates of the fitness costs and benefits of resistance from experimental settings. (ii) Competitive suppression can be a key force preventing resistance from emerging when it is rare, as it is when it first arises. (iii) Drug treatment profoundly affects the fitness of resistance. Resistance evolution could be slowed by developing drug use policies that consider in-host competition.

16.
Prostate ; 78(13): 1024-1034, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30133756

RESUMO

BACKGROUND: To extend our previous observation of a short-term rise in prostate-specific antigen (PSA) concentration, a marker of prostate inflammation and cell damage, during and immediately following sexually transmitted and systemic infections, we examined the longer-term influence of these infections, both individually and cumulatively, on PSA over a mean of 10 years of follow-up in young active duty U.S. servicemen. METHODS: We measured PSA in serum specimens collected in 1995-7 (baseline) and 2004-6 (follow-up) from 265 men diagnosed with chlamydia (CT), 72 with gonorrhea (GC), 37 with non-chlamydial, non-gonococcal urethritis (NCNGU), 58 with infectious mononucleosis (IM), 91 with other systemic or non-genitourinary infections such as varicella; and 125-258 men with no infectious disease diagnoses in their medical record during follow-up (controls). We examined the influence of these infections on PSA change between baseline and follow-up. RESULTS: The proportion of men with any increase in PSA (>0 ng/mL) over the 10-year average follow-up was significantly higher in men with histories of sexually transmitted infections (CT, GC, and NCNGU; 67.7% vs 60.8%, P = 0.043), systemic infections (66.7% vs 54.4%, P = 0.047), or any infections (all cases combined; 68.5% vs 54.4%, P = 0.003) in their military medical record compared to controls. CONCLUSIONS: While PSA has been previously shown to rise during acute infection, these findings demonstrate that PSA remains elevated over a longer period. Additionally, the overall infection burden, rather than solely genitourinary-specific infection burden, contributed to these long-term changes, possibly implying a role for the cumulative burden of infections in prostate cancer risk.

17.
Artigo em Inglês | MEDLINE | ID: mdl-29959132

RESUMO

A level of epigenetic programming, encoded by complex sets of chemical marks on DNA and histones, and by context-specific DNA, RNA, protein interactions, that all regulate the structure, organization, and function of the genome, is critical to establish both normal and neoplastic cell identities and functions. This structure-function relationship of the genome encoded by the epigenetic programming can be thought of as an epigenetic cityscape that is built on the underlying genetic landscape. Alterations in the epigenetic cityscape of prostate cancer cells compared with normal prostate tissues have a complex interplay with genetic alterations to drive prostate cancer initiation and progression. Indeed, mutations in genes encoding epigenetic enzymes are often observed in human cancers including prostate cancer. Interestingly, alterations in the prostate cancer epigenetic cityscape can be highly recurrent, a facet that can be exploited for development of biomarkers and potentially as therapeutic targets.

19.
Sci Total Environ ; 642: 742-753, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29920461

RESUMO

Biogeochemical hotspots are pervasive at terrestrial-aquatic interfaces, particularly within groundwater-surface water mixing zones (hyporheic zones), and they are critical to understanding spatiotemporal variation in biogeochemical cycling. Here, we use multi 'omic comparisons of hotspots to low-activity sediments to gain mechanistic insight into hyporheic zone organic matter processing. We hypothesized that microbiome structure and function, as described by metagenomics and metaproteomics, would distinguish hotspots from low-activity sediments by shifting metabolism towards carbohydrate-utilizing pathways and elucidate discrete mechanisms governing organic matter processing in each location. We also expected these differences to be reflected in the metabolome, whereby hotspot carbon (C) pools and metabolite transformations therein would be enriched in sugar-associated compounds. In contrast to expectations, we found pronounced phenotypic plasticity in the hyporheic zone microbiome that was denoted by similar microbiome structure, functional potential, and expression across sediments with dissimilar metabolic rates. Instead, diverse nitrogenous metabolites and biochemical transformations characterized hotspots. Metabolomes also corresponded more strongly to aerobic metabolism than bulk C or N content only (explaining 67% vs. 42% and 37% of variation respectively), and bulk C and N did not improve statistical models based on metabolome composition alone. These results point to organic nitrogen as a significant regulatory factor influencing hyporheic zone organic matter processing. Based on our findings, we propose incorporating knowledge of metabolic pathways associated with different chemical fractions of C pools into ecosystem models will enhance prediction accuracy.

20.
Cancer Cell ; 33(6): 1004-1016.e5, 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-29894688

RESUMO

Adhesion G protein-coupled receptors (ADGRs) encompass 33 human transmembrane proteins with long N termini involved in cell-cell and cell-matrix interactions. We show the ADGRB1 gene, which encodes Brain-specific angiogenesis inhibitor 1 (BAI1), is epigenetically silenced in medulloblastomas (MBs) through a methyl-CpG binding protein MBD2-dependent mechanism. Knockout of Adgrb1 in mice augments proliferation of cerebellar granule neuron precursors, and leads to accelerated tumor growth in the Ptch1+/- transgenic MB mouse model. BAI1 prevents Mdm2-mediated p53 polyubiquitination, and its loss substantially reduces p53 levels. Reactivation of BAI1/p53 signaling axis by a brain-permeable MBD2 pathway inhibitor suppresses MB growth in vivo. Altogether, our data define BAI1's physiological role in tumorigenesis and directly couple an ADGR to cancer formation.

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