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1.
Nature ; 582(7813): 586-591, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494005

RESUMO

Deregulation of metabolism and disruption of genome integrity are hallmarks of cancer1. Increased levels of the metabolites 2-hydroxyglutarate, succinate and fumarate occur in human malignancies owing to somatic mutations in the isocitrate dehydrogenase-1 or -2 (IDH1 or IDH2) genes, or germline mutations in the fumarate hydratase (FH) and succinate dehydrogenase genes (SDHA, SDHB, SDHC and SDHD), respectively2-4. Recent work has made an unexpected connection between these metabolites and DNA repair by showing that they suppress the pathway of homology-dependent repair (HDR)5,6 and confer an exquisite sensitivity to inhibitors of poly (ADP-ribose) polymerase (PARP) that are being tested in clinical trials. However, the mechanism by which these oncometabolites inhibit HDR remains poorly understood. Here we determine the pathway by which these metabolites disrupt DNA repair. We show that oncometabolite-induced inhibition of the lysine demethylase KDM4B results in aberrant hypermethylation of histone 3 lysine 9 (H3K9) at loci surrounding DNA breaks, masking a local H3K9 trimethylation signal that is essential for the proper execution of HDR. Consequently, recruitment of TIP60 and ATM, two key proximal HDR factors, is substantially impaired at DNA breaks, with reduced end resection and diminished recruitment of downstream repair factors. These findings provide a mechanistic basis for oncometabolite-induced HDR suppression and may guide effective strategies to exploit these defects for therapeutic gain.


Assuntos
Cromatina/metabolismo , Reparo do DNA , Recombinação Homóloga , Neoplasias/metabolismo , Transdução de Sinais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Quebras de DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Recombinação Homóloga/efeitos dos fármacos , Humanos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Lisina Acetiltransferase 5/metabolismo , Metilação/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Transdução de Sinais/efeitos dos fármacos
2.
Conserv Biol ; : e14296, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770838

RESUMO

Marine protected areas (MPAs) globally serve conservation and fisheries management goals, generating positive effects in some marine ecosystems. Surf zones and sandy beaches, critical ecotones bridging land and sea, play a pivotal role in the life cycles of numerous fish species and serve as prime areas for subsistence and recreational fishing. Despite their significance, these areas remain understudied when evaluating the effects of MPAs. We compared surf zone fish assemblages inside and outside MPAs across 3 bioregions in California (USA). Using seines and baited remote underwater videos (BRUVs), we found differences in surf zone fish inside and outside MPAs in one region. Inside south region MPAs, we observed higher abundance (Tukey's honest significant difference [HSD] = 0.83, p = 0.0001) and richness (HSD = 0.22, p = 0.0001) in BRUVs and greater biomass (HSD = 0.32, p = 0.0002) in seine surveys compared with reference sites. Selected live-bearing, fished taxa were positively affected by MPAs. Elasmobranchs displayed greater abundance in BRUV surveys and higher biomass in seine surveys inside south region MPAs (HSD = 0.35, p = 0.0003 and HSD = 0.23, p = 0.008, respectively). Although we observed no overall MPA signal for Embiotocidae, abundances of juvenile and large adult barred surfperch (Amphistichus argenteus), the most abundant fished species, were higher inside MPAs (K-S test D = 0.19, p < 0.0001). Influence of habitat characteristics on MPA performance indicated surf zone width was positively associated with fish abundance and biomass but negatively associated with richness. The south region had the largest positive effect size on all MPA performance metrics. Our findings underscored the variability in species richness and composition across regions and survey methods that significantly affected differences observed inside and outside MPAs. A comprehensive assessment of MPA performance should consider specific taxa, their distribution, and the effects of habitat factors and geography.


Evaluación de la influencia de las áreas marinas protegidas sobre los peces de la zona de rompientes Resumen Las áreas marinas protegidas (AMP) cumplen los objetivos de conservación y manejo de pesquerías a nivel mundial, lo que genera efectos positivos en algunos ecosistemas marinos. Las zonas de rompientes y las playas arenosas, ecotonos importantes que conectan la tierra con el mar, tienen un papel esencial en el ciclo de vida de varios peces y fungen como áreas óptimas para la pesca recreativa y de sustento. A pesar de su importancia, estas áreas están poco estudiadas con respecto a la evaluación del efecto de las AMP. Comparamos la composición de peces del área de rompientes dentro y fuera de las AMP de tres bioregiones de California, EUA. Usamos chinchorros y videos submarinos con carnada (BRUVs) y descubrimos diferencias en los peces de la zona de rompientes dentro y fuera de las AMP en una región. Dentro de las AMP de la región sur observamos una mayor abundancia (diferencia significativa honesta de Tukey [DSH]  =  0.83, p = 0.0001) y riqueza (DSH  =  0.22, p = 0.0001) en los BRUV y una mayor biomasa (DSH  =  0.32, p = 0.0002) en los censos con chinchorro en comparación con los sitios de referencia. Los taxones seleccionados de peces de sustento fueron afectados de manera positiva por las AMP. Los elasmobranquios mostraron una mayor abundancia en los BRUV y una mayor biomasa en los censos con chinchorro dentro de las AMP de la región sur (DSH  =  0.35, p = 0.0003 y DSH  =  0.23, p = 0.008, respectivamente). Aunque no observamos una señal generalizada de las AMP para la familia Embiotocidae, la abundancia de Amphistichus argenteus juveniles y adultos, la especie pescada más abundante, fue mayor dentro de las AMP (prueba K­S D  =  0.19, p < 0.0001). La influencia de las características del hábitat sobre el desempeño de las AMP indicó que el ancho de la zona de rompientes está asociado de forma positiva con la abundancia y biomasa de los peces, pero de forma negativa con la riqueza. La región sur tuvo el mayor tamaño de efecto positivo sobre todas las medidas de desempeño de las AMP. Nuestros hallazgos destacan la variabilidad en la riqueza y composición de especies en todas las regiones y los censos que afectan significativamente las diferencias observadas dentro y fuera de las AMP. Una evaluación completa del desempeño de las AMP debe considerar taxones específicos, su distribución y el efecto de los factores de hábitat y la geografía.

3.
J Nat Prod ; 87(5): 1416-1425, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38687902

RESUMO

In nature, proanthocyanidins (PACs) with A-type linkages are relatively rare, likely due to biosynthetic constraints in the formation of additional ether bonds to be introduced into the more common B-type precursors. However, A-type linkages confer greater structural rigidity on PACs than do B-type linkages. Prior investigations into the structure-activity relationships (SAR) describing how plant-derived PACs with B- and complex AB-type linkages affect their capacity for dentin biomodification indicate that a higher ratio of double linkages leads to a greater interaction with dentin type I collagen. Thus, A-type PACs emerge as particularly intriguing candidates for interventional functional biomaterials. This study employed a free-radical-mediated oxidation using DPPH to transform trimeric and tetrameric B-type PACs, 2 and 4, respectively, into their exclusively A-type linked analogues, 3 and 5, respectively. The structures and absolute configurations of the semisynthetic products, including the new all-A-type tetramer 5, were determined by comprehensive spectroscopic analysis. Additionally, molecular modeling investigated the conformational characteristics of all trimers and tetramers, 1-5. Our findings suggest that the specific interflavan linkages significantly impact the flexibility and low-energy conformations of the connected monomeric units, which conversely can affect the bioactive conformations relevant for dentin biomodification.


Assuntos
Proantocianidinas , Proantocianidinas/química , Estrutura Molecular , Relação Estrutura-Atividade
4.
J Shoulder Elbow Surg ; 33(7): 1593-1600, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38527621

RESUMO

HYPOTHESIS: This study aimed to explore the prognostic value of electrodiagnostic studies (EDS) to clarify their utility in clinical practice prior to cubital tunnel release surgery and to identify patient factors associated with patient-reported functional improvement after surgery. Our hypothesis was that patients with severe preoperative findings on EDS will tend to experience less functional improvement after surgery given the extent of ulnar nerve compressive injury. METHODS: Patients with cubital tunnel syndrome and preoperative electrodiagnostic data treated from 2012 to 2022 with cubital tunnel release were assessed regarding demographic information, preoperative physical examination findings, EDS findings, postoperative complications, and patient-reported outcomes. Short- to midterm quick Disabilities of the Arm, Shoulder, and Hand questionnaire (qDASH) scores were collected for all patients for further evaluation of preoperative EDS data. Patients were grouped into those who had met the minimal clinically important difference (MCID) in delta qDASH at short- to midterm follow-up and those who did not. EDS data included sensory nerve onset latency, peak latency, amplitude, conduction velocity, as well as motor nerve latency, velocity, and amplitude. Electromyographic (EMG) studies were also reviewed, which included data pertaining to fibrillations, presence of abnormal fasciculation, positive sharp waves, variation in insertional activity, motor unit activity, duration of activity, and presence of increasing polymorphisms. RESULTS: Of the 257 patients included, 160 (62.0%) were found to meet the MCID for short- to midterm qDASH scores. There were no significant differences between patients who did or did not meet the MCID regarding baseline demographics, comorbidities, preoperative examination findings, and operative technique. Patients who met MCID tended to have lower complication (3.80% vs. 7.20%, P = .248) and revision (0.60% vs. 4.10%, P = .069) rates, but these findings were not statistically significant. The cubital tunnel severity as determined by the EDS was similar between cohorts (14.1% vs. 14.3%, P = .498). Analysis of EMG testing showed there were no significant differences in preoperative, short- to midterm qDASH, or delta short- to midterm qDASH scores for patients with or without abnormal EMG findings. Multivariate regression suggested that only age (P = .003) was associated with larger delta qDASH scores. CONCLUSION: Patient-reported preoperative disease severity may predict the expected postoperative change in ulnar nerve functional improvement, and EDS may not have prognostic value for patients undergoing cubital tunnel decompression. Therefore, physicians may suggest surgical treatment without positive EDS findings and still expect postoperative improvement in functional outcomes.


Assuntos
Síndrome do Túnel Ulnar , Eletrodiagnóstico , Humanos , Síndrome do Túnel Ulnar/cirurgia , Síndrome do Túnel Ulnar/diagnóstico , Masculino , Pessoa de Meia-Idade , Feminino , Eletrodiagnóstico/métodos , Adulto , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Prognóstico , Eletromiografia/métodos , Descompressão Cirúrgica/métodos , Índice de Gravidade de Doença , Valor Preditivo dos Testes
5.
Artigo em Inglês | MEDLINE | ID: mdl-38599453

RESUMO

HYPOTHESIS: The purpose of this study was to compare inter- and intraobserver agreement of a novel intraoperative subluxation classification for patients undergoing ulnar nerve surgery at the elbow. We hypothesize there will be strong inter- and intraobserver agreement of the 4-category classification system, and reviewers will have substantial confidence while reviewing the classification system. METHODS: Four blinded fellowship-trained orthopedic hand surgeons reviewed 25 videos in total on 2 separate viewings, 21 days apart. Variables collected were ulnar subluxation classification (A, B, C, or D) and a confidence metric. Subsequent to primary data collection, classification grading was stratified into A/B or C/D subgroups for further analysis. Cohen κ scores were used to evaluate all variables collected in this study. The interpretation of κ scores included ≤0.0 as no agreement, 0.01-0.20 as none to slight, 0.21-0.40 as fair, 0.41-0.60 as moderate, 0.61-0.80 as substantial, and 0.81-1.0 as almost perfect agreement. RESULTS: Interobserver agreement of subluxation classification as a 4-category scale demonstrated a moderate agreement on first viewing, second viewing, and when both viewings were combined (κ = 0.51, 0.51, and 0.51 respectively). Seventy-five percent (3 of 4) of reviewers had moderate intraobserver agreement for ulnar nerve subluxation classification, whereas 1 reviewer had substantial intraobserver classification (κ = 0.72). Overall, there was high confidence in 65% of classification scores in the second round of viewing, which improved from 58% in the first viewing round. When ulnar subluxation classification selections were regrouped into classes A/B or C/D, 100% of reviewers had substantial interobserver (κ = 0.74-0.75) and substantial to almost perfect intraobserver (κ = 0.71-0.91) agreement. CONCLUSIONS: The 4-category classification was reproducible within and between reviewers. Agreement appeared to increase when simplifying the classification to 2 categories, which may provide guidance to surgical decision making. The validation of a reproducible classification scheme for intraoperative ulnar subluxation may aid with decision making and further postoperative outcomes research.

6.
Hum Brain Mapp ; 44(6): 2493-2508, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36763547

RESUMO

Millions of children sustain a concussion annually. Concussion disrupts cellular signaling and neural pathways within the brain but the resulting metabolic disruptions are not well characterized. Magnetic resonance spectroscopy (MRS) can examine key brain metabolites (e.g., N-acetyl Aspartate (tNAA), glutamate (Glx), creatine (tCr), choline (tCho), and myo-Inositol (mI)) to better understand these disruptions. In this study, we used MRS to examine differences in brain metabolites between children and adolescents with concussion versus orthopedic injury. Children and adolescents with concussion (n = 361) or orthopedic injury (OI) (n = 184) aged 8 to 17 years were recruited from five emergency departments across Canada. MRS data were collected from the left dorsolateral prefrontal cortex (L-DLPFC) using point resolved spectroscopy (PRESS) at 3 T at a mean of 12 days post-injury (median 10 days post-injury, range 2-33 days). Univariate analyses for each metabolite found no statistically significant metabolite differences between groups. Within each analysis, several covariates were statistically significant. Follow-up analyses designed to account for possible confounding factors including age, site, scanner, vendor, time since injury, and tissue type (and interactions as appropriate) did not find any metabolite group differences. In the largest sample of pediatric concussion studied with MRS to date, we found no metabolite differences between concussion and OI groups in the L-DLPFC. We suggest that at 2 weeks post-injury in a general pediatric concussion population, brain metabolites in the L-DLPFC are not specifically affected by brain injury.


Assuntos
Concussão Encefálica , Encéfalo , Adolescente , Humanos , Criança , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/metabolismo , Ácido Glutâmico/metabolismo , Creatina/metabolismo , Colina/metabolismo , Ácido Aspártico , Inositol/metabolismo
7.
Reprod Biomed Online ; 44(1): 81-92, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34674940

RESUMO

Targeted cancer therapy is rapidly evolving the landscape of personalized health care. Novel approaches to selectively impeding tumour growth carry significant potential to improve survival outcomes, particularly for reproductive-aged patients harbouring treatment refractory disease. Current agents fall within two classes: immunotherapy and small molecule inhibitors. These are collectively divided into the following subclasses: monoclonal antibodies; immunomodulators; adoptive cell therapy; treatment vaccines; kinase inhibitors; proteasome inhibitors; metalloproteinase and heat shock protein inhibitors; and promoters of apoptosis. The short- and long-term effects of these treatments on the female reproductive system are not well understood. As a result, clinicians are rendered unable to appropriately counsel women on downstream effects to their fertility. Data-driven consensus recommendations are desperately needed. This review aims to characterize the effect of targeted cancer therapy on the female hypothalamic-pituitary-ovary axis, direct ovarian function and conception.


Assuntos
Imunoterapia , Neoplasias , Adulto , Feminino , Fertilidade , Humanos , Fatores Imunológicos/uso terapêutico , Neoplasias/tratamento farmacológico , Ovário , Reprodução
8.
PLoS Genet ; 14(12): e1007791, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30517106

RESUMO

The ApoE ε4 allele is the most significant genetic risk factor for late-onset Alzheimer disease. The risk conferred by ε4, however, differs across populations, with populations of African ancestry showing lower ε4 risk compared to those of European or Asian ancestry. The cause of this heterogeneity in risk effect is currently unknown; it may be due to environmental or cultural factors correlated with ancestry, or it may be due to genetic variation local to the ApoE region that differs among populations. Exploring these hypotheses may lead to novel, population-specific therapeutics and risk predictions. To test these hypotheses, we analyzed ApoE genotypes and genome-wide array data in individuals from African American and Puerto Rican populations. A total of 1,766 African American and 220 Puerto Rican individuals with late-onset Alzheimer disease, and 3,730 African American and 169 Puerto Rican cognitively healthy individuals (> 65 years) participated in the study. We first assessed average ancestry across the genome ("global" ancestry) and then tested it for interaction with ApoE genotypes. Next, we assessed the ancestral background of ApoE alleles ("local" ancestry) and tested if ancestry local to ApoE influenced Alzheimer disease risk while controlling for global ancestry. Measures of global ancestry showed no interaction with ApoE risk (Puerto Rican: p-value = 0.49; African American: p-value = 0.65). Conversely, ancestry local to the ApoE region showed an interaction with the ApoE ε4 allele in both populations (Puerto Rican: p-value = 0.019; African American: p-value = 0.005). ApoE ε4 alleles on an African background conferred a lower risk than those with a European ancestral background, regardless of population (Puerto Rican: OR = 1.26 on African background, OR = 4.49 on European; African American: OR = 2.34 on African background, OR = 3.05 on European background). Factors contributing to the lower risk effect in the ApoE gene ε4 allele are likely due to ancestry-specific genetic factors near ApoE rather than non-genetic ethnic, cultural, and environmental factors.


Assuntos
Doença de Alzheimer/genética , Apolipoproteína E4/genética , Negro ou Afro-Americano/genética , Hispânico ou Latino/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Frequência do Gene , Variação Genética , Genética Populacional , Estudo de Associação Genômica Ampla , Humanos , Masculino , Porto Rico/etnologia , Fatores de Risco
9.
Public Health ; 198: 146-155, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34428607

RESUMO

OBJECTIVES: This study aimed to investigate the extent and key characteristics of academic research and scholarship on the public health community's use of social media for policy advocacy purposes. This will enable an evaluation of extant research and provide insight into directions for future research. STUDY DESIGN: This study was a scoping review of academic literature. METHODS: A scoping review of academic literature published between 1 January 2011 and 31 December 2020 was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework. Boolean searches were conducted using a university library platform, which included databases, such as EBSCO host, Informit, Scopus, and ScienceDirect. Data were extracted using an a priori code frame, and publication, content, and disciplinary characteristics were analysed. The results of coding and screening comparison checks were within acceptable limits. RESULTS: In total, 2672 works from around the world were identified and screened for inclusion. Twenty-two English language articles were included in the final analysis. The public health community's use of social media for policy advocacy purposes has largely been approached from a health perspective, despite research and scholarship about social media in communication and policy disciplines (among others). Reported research aims or questions emphasised functional rather than theoretical contributions. Most analysed works used empirical or case study-based methods and were produced by authors in Western geographies. Among the health issues discussed, tobacco and tobacco control were discussed most frequently. While recognising issues with social media, most publications framed social media as more of an opportunity than a problem. CONCLUSIONS: The public health community's use of social media for policy advocacy purposes is an emerging field. There is considerable potential to expand scholarship and research in this field internationally, especially by integrating transdisciplinary knowledge and perspectives and by applying social media to foster policy change around identified global health challenges. Greater representation of authors from institutions in the Global South is also encouraged, as are applied and theoretical contributions.


Assuntos
Mídias Sociais , Atenção à Saúde , Saúde Global , Humanos , Políticas , Saúde Pública
10.
Alzheimers Dement ; 17(7): 1179-1188, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33522086

RESUMO

INTRODUCTION: Apolipoprotein E (APOE) ε4 confers less risk for Alzheimer's disease (AD) in carriers with African local genomic ancestry (ALA) than APOE ε4 carriers with European local ancestry (ELA). Cell type specific transcriptional variation between the two local ancestries (LAs) could contribute to this disease risk differences. METHODS: Single-nucleus RNA sequencing was performed on frozen frontal cortex of homozygous APOE ε4/ε4 AD patients: seven with ELA, four with ALA. RESULTS: A total of 60,908 nuclei were sequenced. Within the LA region (chr19:44-46Mb), APOE was the gene most differentially expressed, with ELA carriers having significantly more expression (overall P < 1.8E-317 ) in 24 of 32 cell clusters. The transcriptome of one astrocyte cluster, with high APOE ε4 expression and specific to ELA, is suggestive of A1 reactive astrocytes. DISCUSSION: AD patients with ELA expressed significantly greater levels of APOE than ALA APOE ε4 carriers. These differences in APOE expression could contribute to the reduced risk for AD seen in African APOE ε4 carriers.


Assuntos
Doença de Alzheimer , Apolipoproteína E4/genética , População Negra/genética , Análise de Sequência de RNA , População Branca/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Doença de Alzheimer/etnologia , Doença de Alzheimer/genética , Feminino , Heterozigoto , Humanos , Masculino
11.
Oncologist ; 25(7): e1124-e1126, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32369640

RESUMO

Low-grade serous ovarian carcinoma (LGSOC) is known to exhibit chemoresistance. Effective treatment options for recurrent disease are few and often limited to hormone antagonism. Combination of endocrine therapies with MEK-inhibitors displays synergism in preclinical ovarian cancer models, however. This brief communication presents the use of combination anti-estrogenic and MEK-inhibitor therapies, fulvestrant and trametinib, as treatment in a heavily pretreated patient with estrogen receptor-positive, recurrent LGSOC. The dual-therapy regimen was well tolerated and appeared to confer 9 months of progression-free survival. Further investigation is warranted to explore this effect.


Assuntos
Neoplasias Ovarianas , Pirimidinonas , Feminino , Fulvestranto , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Piridonas
12.
Gastroenterol Nurs ; 43(6): E214-E216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33055545

RESUMO

A rise in duodenoscope-associated infections, especially in regard to multidrug-resistant organisms, has led to an increase in scrutiny regarding duodenoscope reprocessing. Endoscopic retrograde cholangiopancreatography scopes have a specialized elevator wire channel, allowing more flexible duct cannulation; however, this channel can be difficult to reprocess with standard techniques. Although strict adherence to manufacturer reprocessing protocols remains the primary means of infection prevention, periodic microbiological surveillance is a Food and Drug Administration-recommended practice that the Medical University of South Carolina has implemented to further prevent duodenoscope-associated infections. The Medical University of South Carolina obtains 2 separate cultures from 2 duodenoscopes every 2 months, which undergo standard speciation and sensitivity and are returned to use once negative at 48 hours. The initial results of the Medical University of South Carolina's surveillance cultures are negative for any multidrug-resistant organisms; however, other centers should consider implementing surveillance cultures into their reprocessing practices and closely monitoring for future endoscope infection prevention modalities.


Assuntos
Duodenoscópios , Contaminação de Equipamentos , Colangiopancreatografia Retrógrada Endoscópica , Desinfecção , Contaminação de Equipamentos/prevenção & controle , Humanos , Controle de Infecções
13.
JAAPA ; 33(1): 47-50, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31880651

RESUMO

Many young athletes are pursuing high-intensity training and choosing to specialize in a single sport before high school. However, a growing body of literature suggests that this approach places children and adolescents at increased risk for physical and mental harm, and does not confer the desired benefit in the development of sport-specific skills. This article reviews concerns associated with early sport specialization, outlines principles of developmentally appropriate physical activity and athletic development, and provides practical guidance and resources to assist clinicians in counseling young athletes and their families.


Assuntos
Desenvolvimento do Adolescente , Atletas , Traumatismos em Atletas , Esgotamento Psicológico , Desenvolvimento Infantil , Esportes , Adolescente , Criança , Cultura , Exercício Físico , Humanos
14.
Osteoporos Int ; 30(2): 403-410, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30306222

RESUMO

Bone remodeling markers (BRMs) are suppressed following the consumption of a meal. Our findings indicate that a single session of continuous moderate-intensity exercise, but not low-volume high-intensity interval exercise, performed 1 h after a meal attenuates the postprandial suppression of BRMs. INTRODUCTION: Acute exercise transiently increases BRMs including osteocalcin (tOC) and the undercarboxylated form of osteocalcin (ucOC), a hormone that is implicated in glucose regulation. The effects of acute exercise and exercise-intensity on postprandial levels of tOC and ucOC are unknown. METHODS: Twenty-seven adults that were overweight or obese (age 30 ± 1 years; BMI 30 ± 1 kg∙m-2; mean ± SEM) were randomly allocated to perform a single session of low-volume high-intensity interval exercise (LV-HIIE; nine females, five males) or continuous moderate-intensity exercise (CMIE; eightfemales, five males) 1 h after consumption of a standard breakfast. Serum tOC, ucOC, and ucOC/tOC were measured at baseline, 1 h, and 3 h after breakfast consumption on a rest day (no exercise) and the exercise day (exercise 1 h after breakfast). RESULTS: Compared to baseline, serum tOC and ucOC were suppressed 3 h after breakfast on the rest day (- 10 ± 1% and - 6 ± 2%, respectively; p < 0.05), whereas ucOC/tOC was elevated (2.5 ± 1%; p = 0.08). Compared to the rest day, CMIE attenuated the postprandial-induced suppression of tOC (rest day - 10 ± 2% versus CMIE - 5 ± 2%, p < 0.05) and ucOC (rest day - 6 ± 4% versus CMIE 11 ± 2%, p < 0.05), and increased postprandial ucOC/tOC (rest day 3 ± 2% versus CMIE 15 ± 1%, p < 0.05). In contrast, LV-HIIE did not alter postprandial tOC, ucOC, or ucOC/tOC (all p > 0.1). CONCLUSIONS: Acute CMIE, but not LV-HIIE, attenuates the postprandial-induced suppression of tOC and ucOC. CMIE may be an effective tool to control the circulating levels of BRMs following meal consumption in overweight/obese adults.


Assuntos
Terapia por Exercício/métodos , Osteocalcina/sangue , Sobrepeso/sangue , Adulto , Biomarcadores/sangue , Glicemia/metabolismo , Remodelação Óssea/fisiologia , Ingestão de Alimentos/fisiologia , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Humanos , Insulina/sangue , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , Obesidade/reabilitação , Sobrepeso/fisiopatologia , Sobrepeso/reabilitação , Período Pós-Prandial/fisiologia
15.
Carcinogenesis ; 38(6): 627-637, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472268

RESUMO

The heavy metal nickel is a known carcinogen, and occupational exposure to nickel compounds has been implicated in human lung and nasal cancers. Unlike many other environmental carcinogens, however, nickel does not directly induce DNA mutagenesis, and the mechanism of nickel-related carcinogenesis remains incompletely understood. Cellular nickel exposure leads to signaling pathway activation, transcriptional changes and epigenetic remodeling, processes also impacted by hypoxia, which itself promotes tumor growth without causing direct DNA damage. One of the mechanisms by which hypoxia contributes to tumor growth is the generation of genomic instability via down-regulation of high-fidelity DNA repair pathways. Here, we find that nickel exposure similarly leads to down-regulation of DNA repair proteins involved in homology-dependent DNA double-strand break repair (HDR) and mismatch repair (MMR) in tumorigenic and non-tumorigenic human lung cells. Functionally, nickel induces a defect in HDR capacity, as determined by plasmid-based host cell reactivation assays, persistence of ionizing radiation-induced DNA double-strand breaks and cellular hypersensitivity to ionizing radiation. Mechanistically, we find that nickel, in contrast to the metalloid arsenic, acutely induces transcriptional repression of HDR and MMR genes as part of a global transcriptional pattern similar to that seen with hypoxia. Finally, we find that exposure to low-dose nickel reduces the activity of the MLH1 promoter, but only arsenic leads to long-term MLH1 promoter silencing. Together, our data elucidate novel mechanisms of heavy metal carcinogenesis and contribute to our understanding of the influence of the microenvironment on the regulation of DNA repair pathways.


Assuntos
Enzimas Reparadoras do DNA , Reparo do DNA/efeitos dos fármacos , Neoplasias Pulmonares/genética , Pulmão/metabolismo , Níquel/toxicidade , Oligoelementos/toxicidade , Arsenitos/toxicidade , Hipóxia Celular/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/efeitos da radiação , Regulação para Baixo , Instabilidade Genômica , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Teratogênicos/toxicidade
16.
Osteoporos Int ; 28(8): 2265-2273, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28289780

RESUMO

Undercarboxylated osteocalcin (ucOC) may play a role in glucose homeostasis and cardiometabolic health. This review examines the epidemiological and interventional evidence associating osteocalcin (OC) and ucOC with metabolic risk and cardiovascular disease. The complexity in assessing such correlations, due to the observational nature of human studies, is discussed. Several studies have reported that higher levels of ucOC and OC are correlated with lower fat mass and HbA1c. In addition, improved measures of glycaemic control via pharmacological and non-pharmacological (e.g. exercise or diet) interventions are often associated with increased circulating levels of OC and/or ucOC. There is also a relationship between lower circulating OC and ucOC and increased measures of vascular calcification and cardiovascular disease. However, not all studies have reported such relationship, some with contradictory findings. Equivocal findings may arise because of the observational nature of the studies and the inability to directly assess the relationship between OC and ucOC on glycaemic control and cardiovascular health in humans. Studying OC and ucOC in humans is further complicated due to numerous confounding factors such as sex differences, menopausal status, vitamin K status, physical activity level, body mass index, insulin sensitivity (normal/insulin resistance/T2DM), tissue-specific effects and renal function among others. Current observational and indirect interventional evidence appears to support a relationship between ucOC with metabolic and cardiovascular disease. There is also emerging evidence to suggest a direct role of ucOC in human metabolism. Further mechanistic studies are required to (a) clarify causality, (b) explore mechanisms involved and


Assuntos
Doenças Cardiovasculares/metabolismo , Estilo de Vida , Síndrome Metabólica/metabolismo , Osteocalcina/fisiologia , Glicemia/metabolismo , Exercício Físico/fisiologia , Humanos , Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Osteocalcina/efeitos dos fármacos , Vitamina K/farmacologia
17.
Br J Dermatol ; 177(4): 1043-1051, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28617976

RESUMO

BACKGROUND: Atopic dermatitis (AD) has been associated with cardiovascular risk factors and diseases, but epidemiological studies to date have found conflicting results. OBJECTIVES: To determine the associations of AD with hypertension, type 2 diabetes (T2D), myocardial infarction (MI) and stroke. METHODS: We conducted a cross-sectional analysis of baseline data from the Canadian Partnership for Tomorrow Project, which includes Canadian residents aged 30-74 years living in British Columbia, Alberta, Ontario, Quebec and the Atlantic Provinces. We excluded participants with incomplete data on AD, hypertension, T2D, MI or stroke, who had type 1 or gestational diabetes or who developed any of the outcomes at an age prior to a diagnosis of AD. This left 259 119 participants in our analysis. We used logistic regression to calculate age- and sex-, and multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) between AD and subsequent hypertension, T2D, MI and stroke. RESULTS: AD was reported by 21 379 (8·4%) participants. In total, 52 787 cases of hypertension, 12 739 cases of T2D, 4390 cases of MI and 2235 cases of stroke were reported by participants at enrolment. In the multivariable-adjusted model, AD was associated with decreased odds of hypertension (OR 0·87, 95% CI 0·83-0·90), T2D (OR 0·78, 95% CI 0·71-0·84), MI (OR 0·87, 95% CI 0·75-1·00) and stroke (OR 0·79, 95% CI 0·66-0·95). CONCLUSIONS: We did not find evidence of a positive association between AD and subsequent hypertension, T2D, MI or stroke; AD was inversely associated with these outcomes in our study. Given our findings and the conflicting literature, AD is likely not a major risk factor for cardiovascular disease.


Assuntos
Dermatite Atópica/complicações , Diabetes Mellitus Tipo 2/etiologia , Hipertensão/etiologia , Infarto do Miocárdio/etiologia , Acidente Vascular Cerebral/etiologia , Adulto , Idade de Início , Idoso , Canadá/epidemiologia , Estudos Transversais , Dermatite Atópica/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Fumar/epidemiologia , Acidente Vascular Cerebral/epidemiologia
18.
Mol Ecol ; 24(6): 1248-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25689603

RESUMO

Previous work suggests that larvae from Sydney rock oysters that have been selectively bred for fast growth and disease resistance are more resilient to the impacts of ocean acidification than nonselected, wild-type oysters. In this study, we used proteomics to investigate the molecular differences between oyster populations in adult Sydney rock oysters and to identify whether these form the basis for observations seen in larvae. Adult oysters from a selective breeding line (B2) and nonselected wild types (WT) were exposed for 4 weeks to elevated pCO2 (856 µatm) before their proteomes were compared to those of oysters held under ambient conditions (375 µatm pCO2 ). Exposure to elevated pCO2 resulted in substantial changes in the proteomes of oysters from both the selectively bred and wild-type populations. When biological functions were assigned, these differential proteins fell into five broad, potentially interrelated categories of subcellular functions, in both oyster populations. These functional categories were energy production, cellular stress responses, the cytoskeleton, protein synthesis and cell signalling. In the wild-type population, proteins were predominantly upregulated. However, unexpectedly, these cellular systems were downregulated in the selectively bred oyster population, indicating cellular dysfunction. We argue that this reflects a trade-off, whereby an adaptive capacity for enhanced mitochondrial energy production in the selectively bred population may help to protect larvae from the effects of elevated CO2 , whilst being deleterious to adult oysters.


Assuntos
Dióxido de Carbono/análise , Ostreidae/genética , Proteoma/genética , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cruzamento , Monitoramento Ambiental/métodos
19.
Nucleic Acids Res ; 41(4): 2328-39, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23303771

RESUMO

It has been long speculated that mammalian Rev3 plays an important, yet unknown role(s) during mammalian development, as deletion of Rev3 causes embryonic lethality in mice, whereas no other translesion DNA synthesis polymerases studied to date are required for mouse embryo development. Here, we report that both subunits of Polζ (Rev3 and Rev7) show an unexpected increase in expression during G(2)/M phase, but they localize independently in mitotic cells. Experimental depletion of Rev3 results in a significant increase in anaphase bridges, chromosomal breaks/gaps and common fragile site (CFS) expression, whereas Rev7 depletion primarily causes lagging chromosome defect with no sign of CFS expression. The genomic instability induced by Rev3 depletion seems to be related to replication stress, as it is further enhanced on aphidicolin treatment and results in increased metaphase-specific Fanconi anemia complementation group D type 2 (FANCD2) foci formation, as well as FANCD2-positive anaphase bridges. Indeed, a long-term depletion of Rev3 in cultured human cells results in massive genomic instability and severe cell cycle arrest. The aforementioned observations collectively support a notion that Rev3 is required for the efficient replication of CFSs during G(2)/M phase, and that the resulting fragile site instability in Rev3 knockout mice may trigger cell death during embryonic development.


Assuntos
Sítios Frágeis do Cromossomo , Proteínas de Ligação a DNA/fisiologia , DNA Polimerase Dirigida por DNA/fisiologia , Divisão Celular , Proliferação de Células , Células Cultivadas , Quebra Cromossômica , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/análise , Fase G2 , Instabilidade Genômica , Histonas/análise , Humanos , Proteínas Mad2 , Mitose/genética , Inibidores da Síntese de Ácido Nucleico , Proteínas/antagonistas & inibidores , Proteínas/metabolismo
20.
Br J Cancer ; 111(9): 1814-23, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25051410

RESUMO

BACKGROUND: Earlier studies have shown raised risks of leukaemia and non-Hodgkin lymphoma in children, teenagers and young adults resident either at birth or diagnosis in Seascale. Some increases in cancer risk in these age groups have also been noted among those living around Dounreay. We aimed to update previous analyses relating to areas close to these nuclear installations by considering data from an additional 16 years of follow-up. METHODS: Cross-sectional analyses compared cancer incidence rates for 1963-2006 among those aged 0-24 years at diagnosis living in geographically specified areas around either Sellafield or Dounreay with general population rates. Cancer incidence for the period 1971-2006 among the cohort of Cumbrian births between 1950 and 2006 was compared to national incidence for 1971-2006 using person-years analysis. Cancer among those born in the postcode sector closest to Dounreay was compared with that among those born in the three adjoining postcode sectors. Analyses considered both cancer overall and ICD-O-3 defined diagnostic subgroups including leukaemia, central nervous system tumours and other malignancies. RESULTS: Apart from previously reported raised risks, no new significantly increased risks for cancer overall or any diagnostic subgroup were found among children or teenagers and young adults living around either nuclear installation. Individuals born close to the installations from 1950 to 2006 were not shown to be at any increased risk of cancer during the period 1971 to date. CONCLUSIONS: Analysis of recent data suggests that children, teenagers and young adults currently living close to Sellafield and Dounreay are not at an increased risk of developing cancer. Equally, there is no evidence of any increased cancer risk later in life among those resident in these areas at birth.


Assuntos
Neoplasias Induzidas por Radiação/epidemiologia , Reatores Nucleares , Cinza Radioativa/efeitos adversos , Características de Residência , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Neoplasias Induzidas por Radiação/etiologia , Prognóstico , Fatores de Risco , Reino Unido/epidemiologia , Adulto Jovem
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