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1.
Proc Natl Acad Sci U S A ; 121(10): e2313205121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408235

RESUMO

Marine protected areas (MPAs) are widely used for ocean conservation, yet the relative impacts of various types of MPAs are poorly understood. We estimated impacts on fish biomass from no-take and multiple-use (fished) MPAs, employing a rigorous matched counterfactual design with a global dataset of >14,000 surveys in and around 216 MPAs. Both no-take and multiple-use MPAs generated positive conservation outcomes relative to no protection (58.2% and 12.6% fish biomass increases, respectively), with smaller estimated differences between the two MPA types when controlling for additional confounding factors (8.3% increase). Relative performance depended on context and management: no-take MPAs performed better in areas of high human pressure but similar to multiple-use in remote locations. Multiple-use MPA performance was low in high-pressure areas but improved significantly with better management, producing similar outcomes to no-take MPAs when adequately staffed and appropriate use regulations were applied. For priority conservation areas where no-take restrictions are not possible or ethical, our findings show that a portfolio of well-designed and well-managed multiple-use MPAs represents a viable and potentially equitable pathway to advance local and global conservation.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Humanos , Biomassa , Peixes , Ecossistema
2.
Am Heart J ; 269: 72-83, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38061683

RESUMO

BACKGROUND: Despite guidelines and strong evidence supporting intravenous thrombolysis and endovascular thrombectomy for acute stroke, access to these interventions remains a challenge. The objective of the IMPROVE stroke care program was to accelerate acute stroke care delivery by implementing best practices and improving the regional systems of care within comprehensive stroke networks. METHODS: The IMPROVE Stroke Care program was a prospective quality improvement program based on established models used in acute coronary care. Nine hub hospitals (comprehensive stroke centers), 52 regional/community referral hospitals (spokes), and over 100 emergency medical service agencies participated. Through 6 regional meetings, 49 best practices were chosen for improvement by the participating sites. Over 2 years, progress was tracked and discussed weekly and performance reviews were disseminated quarterly. RESULTS: Data were collected on 21,647 stroke code activations of which 8,502 (39.3%) activations had a final diagnosis of stroke. There were 7,226 (85.0%) ischemic strokes, and thrombolytic therapy was administered 2,814 times (38.9%). There was significant overall improvement in the proportion that received lytic therapy within 45 minutes (baseline of 44.6%-60.4%). The hubs were more frequently achieving this at baseline, but both site types improved. A total of 1,455 (17.1%) thrombectomies were included in the data of which 401 (27.6%) were transferred from a spoke. There was no clinically significant change in door-to-groin times for hub-presenting thrombectomy patients, however, significant improvement occurred for transferred cases, 46 minutes (interquartile range [IQR] 36, 115.5) at baseline to 27 minutes (IQR 10, 59). CONCLUSIONS: The IMPROVE program approach was successful at improving the delivery of thrombolytic intervention across the consortium at both spoke and hub sites through collaborative efforts to operationalize guideline-based care through iterative sharing of performance and best practices for implementation. Our approach allowed identification of both opportunities for improvement and operational best practices providing guidance on how best to create a regional stroke care network and operationalize the published acute stroke care guidelines.


Assuntos
Melhoria de Qualidade , Acidente Vascular Cerebral , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Fibrinolíticos/uso terapêutico , Terapia Trombolítica , Resultado do Tratamento , Tempo para o Tratamento
3.
HGG Adv ; : 100240, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37718511

RESUMO

Carriers of BRCA1 germline pathogenic variants are at substantially higher risk of developing breast and ovarian cancer than the general population. Accurate identification of at-risk individuals is crucial for risk stratification and the implementation of targeted preventive and therapeutic interventions. Despite significant progress in variant classification efforts, a sizable portion of reported BRCA1 variants remain as variants of uncertain clinical significance (VUS). Variants leading to premature protein termination and loss of essential functional domains are typically classified as pathogenic. However, the impact of frameshift variants that result in an extended incorrect terminus (EIT) is not clear. Using validated functional assays, we conducted a systematic functional assessment of 17 previously reported BRCA1 EIT variants and concluded that 16 constitute loss of function variants. This suggests that most EITs are likely to be pathogenic. However, one variant, c.5578dup, displayed protein expression level, affinity to known binding partners, and activity in transcription and homologous recombination assays comparable to the wild-type BRCA1 protein. Twenty-three additional carriers of c.5578dup were identified at a US clinical diagnostic lab and assessed using a family history likelihood model providing, in combination with the functional data, a likely benign interpretation. These results, consistent with family history data in the current study and available data from ClinVar, indicate that most, but not all, BRCA1 variants leading to EIT constitute loss of function variants, and underscore the need for comprehensive assessment of individual variants.

4.
Sci Rep ; 12(1): 16203, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171434

RESUMO

BRCA1 (Breast Cancer 1, early onset) is linked to breast and ovarian cancer predisposition. Still, the risks conferred by a significant portion of BRCA1 variants identified in the population remains unknown. Most of these variants of uncertain significance are missense alterations. However, the functional implications of small in-frame deletions and/or insertions (indels) are also difficult to predict. Our group has previously evaluated the functional impact of 347 missense variants using an extensively validated transcriptional activity assay. Here we show a systematic assessment of 30 naturally occurring in-frame indels located at the C-terminal region of BRCA1. We identified positions sensitive and tolerant to alterations, expanding the knowledge of structural determinants of BRCA1 function. We further designed and assessed the impact of four single codon deletions in the tBRCT linker region and six nonsense variants at the C-terminus end of BRCA1. Amino acid substitutions, deletions or insertions in the disordered region do not significantly impact activity and are not likely to constitute pathogenic alleles. On the other hand, a sizeable fraction of in-frame indels at the BRCT domain significantly impact function. We then use a Bayesian integrative statistical model to derive the probability of pathogenicity for each variant. Our data highlights the importance of assessing the impact of small in-frame indels in BRCA1 to improve risk assessment and clinical decisions for carriers.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Alelos , Substituição de Aminoácidos , Proteína BRCA1/metabolismo , Teorema de Bayes , Feminino , Genes BRCA1 , Predisposição Genética para Doença , Humanos , Mutação de Sentido Incorreto , Neoplasias Ovarianas/genética
5.
NPJ Genom Med ; 7(1): 35, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35665744

RESUMO

Loss-of-function variants in the BRCA1 and BRCA2 susceptibility genes predispose carriers to breast and/or ovarian cancer. The use of germline testing panels containing these genes has grown dramatically, but the interpretation of the results has been complicated by the identification of many sequence variants of undefined cancer relevance, termed "Variants of Uncertain Significance (VUS)." We have developed functional assays and a statistical model called VarCall for classifying BRCA1 and BRCA2 VUS. Here we describe a multifactorial extension of VarCall, called VarCall XT, that allows for co-analysis of multiple forms of genetic evidence. We evaluated the accuracy of models defined by the combinations of functional, in silico protein predictors, and family data for VUS classification. VarCall XT classified variants of known pathogenicity status with high sensitivity and specificity, with the functional assays contributing the greatest predictive power. This approach could be used to identify more patients that would benefit from personalized cancer risk assessment and management.

6.
BMJ Neurol Open ; 4(1): e000273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35519902

RESUMO

Background/Purpose: Cardiac arrest is a common cause of death and neurological injury; therapeutic cooling for neuroprotection is standard of care. Despite numerous and ongoing trials targeting a specified cooling temperature for a target duration, the concept of temperature dose-the duration spent at a given depth of hypothermia-is not as well explored. Methods: In this retrospective study, we examined 66 patients 18 years of age or older undergoing therapeutic hypothermia for cardiac arrest between 2007 and 2010 to assess the relationship of temperature dose with outcomes. Demographic, clinical, outcome and temperature data were collected. Demographic and clinical data underwent bivariate regression analysis for association with outcome. Time-temperature curves were divided into pre-determined temperature thresholds and assessed by logistic regression analysis for association with outcome. A second, multivariate regression analysis was performed controlling for factors associated with poor outcomes. Results: Old age was significantly associated with poor outcome and a shockable arrest rhythm was significantly associated with positive outcome. Subjects spent an average of 2.82 hours below 35°C, 7.31 hours ≥35°C to ≤36.5°C, 24.75 hours >36.5 to <38.0°C and 7.06 hours ≥38°C. Logistic regression analysis revealed borderline significant positive association between good outcome and time at a cooling depth (35°C-36.5°C, p=0.05); adjusted for old age, the association became significant (p=0.04). Conclusion: Controlling for old age, longer durations between >35°C, ≤36.5°C during therapeutic hypothermia for cardiac arrest were significantly associated with good clinical outcomes. Time spent within a given temperature range may be useful for measuring the effect of temperature management.

7.
Genet Med ; 23(2): 306-315, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33087888

RESUMO

PURPOSE: BRCA1 pathogenic variant heterozygotes are at a substantially increased risk for breast and ovarian cancer. The widespread uptake of testing has led to a significant increase in the detection of missense variants in BRCA1, the vast majority of which are variants of uncertain clinical significance (VUS), posing a challenge to genetic counseling. Here, we harness a wealth of functional data for thousands of variants to aid in variant classification. METHODS: We have collected, curated, and harmonized functional data for 2701 missense variants representing 24.5% of possible missense variants in BRCA1. Results were harmonized across studies by converting data into binary categorical variables (functional impact versus no functional impact). Using a panel of reference variants we identified a subset of assays with high sensitivity and specificity (≥80%) and apply the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) variant interpretation guidelines to assign evidence criteria for classification. RESULTS: Integration of data from validated assays provided ACMG/AMP evidence criteria in favor of pathogenicity for 297 variants or against pathogenicity for 2058 representing 96.2% of current VUS functionally assessed. We also explore discordant results and identify limitations in the approach. CONCLUSION: High quality functional data are available for BRCA1 missense variants and provide evidence for classification of 2355 VUS according to their pathogenicity.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Proteína BRCA1/genética , Neoplasias da Mama/genética , Feminino , Aconselhamento Genético , Predisposição Genética para Doença , Testes Genéticos , Genômica , Humanos , Neoplasias Ovarianas/genética
8.
NPJ Genom Med ; 5(1): 52, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33293522

RESUMO

Sequencing-based genetic tests to identify individuals at increased risk of hereditary breast and ovarian cancers have resulted in the identification of more than 40,000 sequence variants of BRCA1 and BRCA2. A majority of these variants are considered to be variants of uncertain significance (VUS) because their impact on disease risk remains unknown, largely due to lack of sufficient familial linkage and epidemiological data. Several assays have been developed to examine the effect of VUS on protein function, which can be used to assess their impact on cancer susceptibility. In this study, we report the functional characterization of 88 BRCA2 variants, including several previously uncharacterized variants, using a well-established mouse embryonic stem cell (mESC)-based assay. We have examined their ability to rescue the lethality of Brca2 null mESC as well as sensitivity to six DNA damaging agents including ionizing radiation and a PARP inhibitor. We have also examined the impact of BRCA2 variants on splicing. In addition, we have developed a computational model to determine the probability of impact on function of the variants that can be used for risk assessment. In contrast to the previous VarCall models that are based on a single functional assay, we have developed a new platform to analyze the data from multiple functional assays separately and in combination. We have validated our VarCall models using 12 known pathogenic and 10 neutral variants and demonstrated their usefulness in determining the pathogenicity of BRCA2 variants that are listed as VUS or as variants with conflicting functional interpretation.

9.
J Vis Exp ; (162)2020 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-32894270

RESUMO

By replacing lost or dysfunctional myocardium, tissue regeneration is a promising approach to treat heart failure. However, the challenge of detecting bona fide heart regeneration limits the validation of potential regenerative factors. One method to detect new cardiomyocytes is multicolor lineage tracing with clonal analysis. Clonal analysis experiments can be difficult to undertake, because labeling conditions that are too sparse lack sensitivity for rare events such as cardiomyocyte proliferation, and diffuse labeling limits the ability to resolve clones. Presented here is a protocol to undertake clonal analysis of the neonatal mouse heart by using statistical modeling of nearest neighbor distributions to resolve cardiomyocyte clones. This approach enables resolution of clones over a range of labeling conditions and provides a robust analytical approach for quantifying cardiomyocyte proliferation and regeneration. This protocol can be adapted to other tissues and can be broadly used to study tissue regeneration.


Assuntos
Células Clonais/citologia , Modelos Cardiovasculares , Miócitos Cardíacos/citologia , Animais , Animais Recém-Nascidos , Proliferação de Células , Camundongos
10.
PLoS One ; 15(9): e0237374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877404

RESUMO

Large predators play important ecological roles, yet many are disproportionately imperiled. In marine systems, artificial reefs are often deployed to restore degraded reefs or supplement existing reefs, but it remains unknown whether these interventions benefit large predators. Comparative field surveys of thirty artificial and natural reefs across ~200 km of the North Carolina, USA coast revealed large reef-associated predators were more dense on artificial than natural reefs. This pattern was associated with higher densities of transient predators (e.g. jacks, mackerel, barracuda, sharks) on artificial reefs, but not of resident predators (e.g., grouper, snapper). Further analyses revealed that this pattern of higher transient predator densities on artificial reefs related to reef morphology, as artificial reefs composed of ships hosted higher transient predator densities than concrete reefs. The strength of the positive association between artificial reefs and transient predators increased with a fundamental habitat trait-vertical extent. Taller artificial reefs had higher densities of transient predators, even when accounting for habitat area. A global literature review of high trophic level fishes on artificial and natural habitats suggests that the overall pattern of more predators on artificial habitats is generalizable. Together, these findings provide evidence that artificial habitats, especially those like sunken ships that provide high vertical structure, may support large predators.


Assuntos
Recifes de Corais , Comportamento Predatório/fisiologia , Animais , Peixes/fisiologia , Geografia , Estados Unidos
11.
Cancer Res ; 80(5): 1210-1218, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31932455

RESUMO

Repeated exposure to the acute proinflammatory environment that follows ovulation at the ovarian surface and distal fallopian tube over a woman's reproductive years may increase ovarian cancer risk. To address this, analyses included individual-level data from 558,709 naturally menopausal women across 20 prospective cohorts, among whom 3,246 developed invasive epithelial ovarian cancer (2,045 serous, 319 endometrioid, 184 mucinous, 121 clear cell, 577 other/unknown). Cox models were used to estimate multivariable-adjusted HRs between lifetime ovulatory cycles (LOC) and its components and ovarian cancer risk overall and by histotype. Women in the 90th percentile of LOC (>514 cycles) were almost twice as likely to be diagnosed with ovarian cancer than women in the 10th percentile (<294) [HR (95% confidence interval): 1.92 (1.60-2.30)]. Risk increased 14% per 5-year increase in LOC (60 cycles) [(1.10-1.17)]; this association remained after adjustment for LOC components: number of pregnancies and oral contraceptive use [1.08 (1.04-1.12)]. The association varied by histotype, with increased risk of serous [1.13 (1.09-1.17)], endometrioid [1.20 (1.10-1.32)], and clear cell [1.37 (1.18-1.58)], but not mucinous [0.99 (0.88-1.10), P-heterogeneity = 0.01] tumors. Heterogeneity across histotypes was reduced [P-heterogeneity = 0.15] with adjustment for LOC components [1.08 serous, 1.11 endometrioid, 1.26 clear cell, 0.94 mucinous]. Although the 10-year absolute risk of ovarian cancer is small, it roughly doubles as the number of LOC rises from approximately 300 to 500. The consistency and linearity of effects strongly support the hypothesis that each ovulation leads to small increases in the risk of most ovarian cancers, a risk that cumulates through life, suggesting this as an important area for identifying intervention strategies. SIGNIFICANCE: Although ovarian cancer is rare, risk of most ovarian cancers doubles as the number of lifetime ovulatory cycles increases from approximately 300 to 500. Thus, identifying an important area for cancer prevention research.


Assuntos
Neoplasias Ovarianas/epidemiologia , Ovário/imunologia , Ovulação/imunologia , Idoso , Anticoncepcionais/administração & dosagem , Tubas Uterinas/imunologia , Tubas Uterinas/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/prevenção & controle , Ovário/patologia , Ovulação/efeitos dos fármacos , Modelos de Riscos Proporcionais , Estudos Prospectivos , História Reprodutiva , Medição de Risco , Fatores de Risco
12.
Int J Radiat Biol ; 96(1): 47-56, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30371121

RESUMO

Purpose: Design and characterization of a radiation biodosimetry device are complicated by the fact that the requisite data are not available in the intended use population, namely humans exposed to a single, whole-body radiation dose. Instead, one must turn to model systems. We discuss our studies utilizing healthy, unexposed humans, human bone marrow transplant patients undergoing total body irradiation (TBI), non-human primates subjected to the same irradiation regimen received by the human TBI patients and NHPs given a single, whole-body dose of ionizing radiation.Materials and Methods: We use Bayesian linear mixed models to characterize the association between NHP and human expression patterns in radiation response genes when exposed to a common exposure regimen and across exposure regimens within the same species.Results: We show that population average differences in expression of our radiation response genes from one to another model system are comparable to typical differences between two randomly sampled members of a given model system and that these differences are smaller, on average, for linear combinations of the probe data and for the model-based combinations employed for dose prediction as part of a radiation biodosimetry device.Conclusions: Our analysis suggests that dose estimates based on our gene list will be accurate when applied to humans who have received a single, whole-body exposure to ionizing radiation.


Assuntos
Absorção de Radiação , Animais , Teorema de Bayes , Transplante de Medula Óssea , Relação Dose-Resposta à Radiação , Humanos , Macaca mulatta , Modelos Estatísticos , Exposição à Radiação/efeitos adversos , Especificidade da Espécie , Transcriptoma/efeitos da radiação
13.
Child Obes ; 16(2): 122-128, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31618046

RESUMO

Background: Previous studies show inconsistent relations between child care and obesity, but few assessed longitudinal associations during infancy and even fewer included racially diverse children. We examined associations of time infants spent in child care, both overall and in different types of care, with weight status at 6 and 12 months. Methods: We examined 664 infants living in central North Carolina. We conducted adjusted multivariable linear regressions examining (1) child care from birth to 6 months and 6-month weight-for-length (WFL) z-score, and (2) child care from birth to 12 months and 12-month WFL z-score. We assessed any child care and child care by type, including relative care, informal care by a nonrelative, formal child care, and a combination of care (e.g., relative and informal care). Results: Nearly 70% of infants were black and 49% were female. After adjustment for potential confounders, any child care was not associated with WFL z-score at 6 months (0.07; 95% confidence intervals [CI] -0.02 to 0.16; p = 0.13) or 12 months (0.05; 95% CI -0.02 to 0.12; p = 0.19). However, greater combination care was associated with higher WFL z-score at 6 months (0.68; 95% CI 0.23-1.13; p = 0.003) and greater care by a relative was associated with higher WFL z-score at 12 months (0.16; 95% CI 0.05-0.26; p = 0.005). Conclusions: Although we did not observe associations with any child care, combination care and relative care during infancy were associated with higher weight. Interventions aimed at preventing excessive weight gain in early life may target relatives who provide regular care for infants.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Peso Corporal/fisiologia , Cuidado do Lactente/estatística & dados numéricos , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , North Carolina , Obesidade Pediátrica
14.
Cancer Epidemiol Biomarkers Prev ; 28(7): 1117-1126, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30948450

RESUMO

BACKGROUND: Germline DNA copy number variation (CNV) is a ubiquitous source of genetic variation and remains largely unexplored in association with epithelial ovarian cancer (EOC) risk. METHODS: CNV was quantified in the DNA of approximately 3,500 cases and controls genotyped with the Illumina 610k and HumanOmni2.5M arrays. We performed a genome-wide association study of common (>1%) CNV regions (CNVRs) with EOC and high-grade serous (HGSOC) risk and, using The Cancer Genome Atlas (TCGA), performed in silico analyses of tumor-gene expression. RESULTS: Three CNVRs were associated (P < 0.01) with EOC risk: two large (∼100 kb) regions within the 610k set and one small (<5 kb) region with the higher resolution 2.5M data. Large CNVRs included a duplication at LILRA6 (OR = 2.57; P = 0.001) and a deletion at CYP2A7 (OR = 1.90; P = 0.007) that were strongly associated with HGSOC risk (OR = 3.02; P = 8.98 × 10-5). Somatic CYP2A7 alterations correlated with EGLN2 expression in tumors (P = 2.94 × 10-47). An intronic ERBB4/HER4 deletion was associated with reduced EOC risk (OR = 0.33; P = 9.5 × 10-2), and somatic deletions correlated with ERBB4 downregulation (P = 7.05 × 10-5). Five CNVRs were associated with HGSOC, including two reduced-risk deletions: one at 1p36.33 (OR = 0.28; P = 0.001) that correlated with lower CDKIIA expression in TCGA tumors (P = 2.7 × 10-7), and another at 8p21.2 (OR = 0.52; P = 0.002) that was present somatically where it correlated with lower GNRH1 expression (P = 5.9 × 10-5). CONCLUSIONS: Though CNV appears to not contribute largely to EOC susceptibility, a number of low-to-common frequency variants may influence the risk of EOC and tumor-gene expression. IMPACT: Further research on CNV and EOC susceptibility is warranted, particularly with CNVs estimated from high-density arrays.


Assuntos
Carcinoma Epitelial do Ovário/genética , Variações do Número de Cópias de DNA/genética , Estudo de Associação Genômica Ampla/métodos , Estudos de Casos e Controles , Feminino , Humanos
15.
J Biol Chem ; 294(15): 5980-5992, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30765603

RESUMO

Genetic testing for BRCA1, a DNA repair protein, can identify carriers of pathogenic variants associated with a substantially increased risk for breast and ovarian cancers. However, an association with increased risk is unclear for a large fraction of BRCA1 variants present in the human population. Most of these variants of uncertain clinical significance lead to amino acid changes in the BRCA1 protein. Functional assays are valuable tools to assess the potential pathogenicity of these variants. Here, we systematically probed the effects of substitutions in the C terminus of BRCA1: the N- and C-terminal borders of its tandem BRCT domain, the BRCT-[N-C] linker region, and the α1 and α'1 helices in BRCT-[N] and -[C]. Using a validated transcriptional assay based on a fusion of the GAL4 DNA-binding domain to the BRCA1 C terminus (amino acids 1396-1863), we assessed the functional impact of 99 missense variants of BRCA1. We include the data obtained for these 99 missense variants in a joint analysis to generate the likelihood of pathogenicity for 347 missense variants in BRCA1 using VarCall, a Bayesian integrative statistical model. The results from this analysis increase our understanding of BRCA1 regions less tolerant to changes, identify functional borders of structural domains, and predict the likelihood of pathogenicity for 98% of all BRCA1 missense variants in this region recorded in the population. This knowledge will be critical for improving risk assessment and clinical treatment of carriers of BRCA1 variants.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Modelos Moleculares , Mutação de Sentido Incorreto , Neoplasias Ovarianas , Substituição de Aminoácidos , Proteína BRCA1/química , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Células HEK293 , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Domínios Proteicos , Relação Estrutura-Atividade
16.
Genet Med ; 21(1): 71-80, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884841

RESUMO

PURPOSE: To improve methods for predicting the impact of missense variants of uncertain significance (VUS) in BRCA1 and BRCA2 on protein function. METHODS: Functional data for 248 BRCA1 and 207 BRCA2 variants from assays with established high sensitivity and specificity for damaging variants were used to recalibrate 40 in silico algorithms predicting the impact of variants on protein activity. Additional random forest (RF) and naïve voting method (NVM) metapredictors for both BRCA1 and BRCA2 were developed to increase predictive accuracy. RESULTS: Optimized thresholds for in silico prediction models significantly improved the accuracy of predicted functional effects for BRCA1 and BRCA2 variants. In addition, new BRCA1-RF and BRCA2-RF metapredictors showed area under the curve (AUC) values of 0.92 (95% confidence interval [CI]: 0.88-0.96) and 0.90 (95% CI: 0.84-0.95), respectively. Similarly, the BRCA1-NVM and BRCA2-NVM models had AUCs of 0.93 and 0.90. The RF and NVM models were used to predict the pathogenicity of all possible missense variants in BRCA1 and BRCA2. CONCLUSION: The recalibrated algorithms and new metapredictors significantly improved upon current models for predicting the impact of variants in cancer risk-associated domains of BRCA1 and BRCA2. Prediction of the functional impact of all possible variants in BRCA1 and BRCA2 provides important information about the clinical relevance of variants in these genes.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias Ovarianas/genética , Algoritmos , Neoplasias da Mama/patologia , Simulação por Computador , Feminino , Predisposição Genética para Doença , Humanos , Mutação de Sentido Incorreto/genética , Neoplasias Ovarianas/patologia
17.
Am J Hum Genet ; 102(2): 233-248, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29394989

RESUMO

Many variants of uncertain significance (VUS) have been identified in BRCA2 through clinical genetic testing. VUS pose a significant clinical challenge because the contribution of these variants to cancer risk has not been determined. We conducted a comprehensive assessment of VUS in the BRCA2 C-terminal DNA binding domain (DBD) by using a validated functional assay of BRCA2 homologous recombination (HR) DNA-repair activity and defined a classifier of variant pathogenicity. Among 139 variants evaluated, 54 had ?99% probability of pathogenicity, and 73 had ?95% probability of neutrality. Functional assay results were compared with predictions of variant pathogenicity from the Align-GVGD protein-sequence-based prediction algorithm, which has been used for variant classification. Relative to the HR assay, Align-GVGD significantly (p < 0.05) over-predicted pathogenic variants. We subsequently combined functional and Align-GVGD prediction results in a Bayesian hierarchical model (VarCall) to estimate the overall probability of pathogenicity for each VUS. In addition, to predict the effects of all other BRCA2 DBD variants and to prioritize variants for functional studies, we used the endoPhenotype-Optimized Sequence Ensemble (ePOSE) algorithm to train classifiers for BRCA2 variants by using data from the HR functional assay. Together, the results show that systematic functional assays in combination with in silico predictors of pathogenicity provide robust tools for clinical annotation of BRCA2 VUS.


Assuntos
Algoritmos , Substituição de Aminoácidos , Proteína BRCA2/genética , Neoplasias da Mama/genética , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Sequência de Aminoácidos , Teorema de Bayes , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Expressão Gênica , Testes Genéticos , Humanos , Curva ROC , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
18.
Sci Rep ; 7(1): 549, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28373693

RESUMO

Several transient receptor potential (TRP) ion channels can be directly activated by hot or cold temperature with high sensitivity. However, the structures and molecular mechanism giving rise to their high temperature sensitivity are not fully understood. One hypothesized mechanism assumes that temperature activation is driven by the exposure of hydrophobic residues to solvent. This mechanism further predicts that residues are exposed to solvent in a coordinated fashion, but without necessarily being located in close proximity to each other. However, there is little experimental evidence supporting this mechanism in TRP channels. Here, we combined high-throughput mutagenesis, functional screening, and deep sequencing to identify mutations from a total of ~7,300 TRPV1 random mutant clones. We found that strong decreases in hydrophobicity of amino acids are better tolerated for activation by capsaicin than for activation by hot temperature, suggesting that strong hydrophobicity might be specifically required for temperature activation. Altogether, our work provides initial correlative support for a previously hypothesized temperature mechanism in TRP ion channels.


Assuntos
Aminoácidos/química , Aminoácidos/genética , Interações Hidrofóbicas e Hidrofílicas , Ativação do Canal Iônico , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/genética , Temperatura , Animais , Linhagem Celular , Análise Mutacional de DNA , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Modelos Moleculares , Mutação , Conformação Proteica , Ratos , Relação Estrutura-Atividade , Canais de Cátion TRPV/química
19.
BMJ Open ; 7(2): e013939, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28179416

RESUMO

PURPOSE: Childcare has been associated with obesity in children in cross-sectional and longitudinal studies, although some observed no association. Few studies have focused on care during infancy, a period when children may be especially vulnerable. PARTICIPANTS: The Nurture Study is an observational birth cohort designed to assess longitudinal associations of childcare and the presence of multiple caregivers on infant adiposity and weight trajectories throughout the first year of life. We examine as potential mediators feeding, physical activity, sleep and stress. We completed recruitment in 2015. Of the 860 women who enrolled during pregnancy, 799 delivered a single live infant who met our inclusion criteria. Of those, 666 mothers (77.4%) agreed to participate in the study for themselves and their infants. FINDINGS TO DATE: Among the 666 women in the study, 472 (71%) identified as black, 127 (19%) as white, 7 (1%) as Asian or Asian American, 6 (1%) as Native American and 49 (7%) as other race or more than one race; 43 (7%) identified as Hispanic/Latina. Just under half (48%) had a high school diploma or less, 61% had household incomes <$20 000/year and 59% were married or living with a partner. The mean (SD) infant gestational age was 41.28 weeks (2.29) and birth weight for gestational age z-score was -0.31 (0.93). Just under half (49%) of infants were females, 69% received some human milk and 40% were exclusively breast fed at hospital discharge. Data collection began in 2013, is currently underway, and is scheduled to conclude in late 2016. FUTURE PLANS: Results will help assess the magnitude of associations between childcare in infancy and subsequent obesity. Findings will also inform intervention and policy efforts to improve childcare environments and help prevent obesity in settings where many infants spend time. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov, NCT01788644.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Desenvolvimento Infantil/fisiologia , Cuidado do Lactente/métodos , Obesidade/epidemiologia , Adulto , Peso ao Nascer , Cuidadores , Feminino , Idade Gestacional , Humanos , Renda/estatística & dados numéricos , Lactente , Recém-Nascido , Modelos Lineares , Estudos Longitudinais , Masculino , Mães , Projetos de Pesquisa , Estados Unidos , Adulto Jovem
20.
J R Soc Interface ; 14(127)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28228543

RESUMO

Cell growth and division are processes vital to the proliferation and development of life. Coordination between these two processes has been recognized for decades in a variety of organisms. In the budding yeast Saccharomyces cerevisiae, this coordination or 'size control' appears as an inverse correlation between cell size and the rate of cell-cycle progression, routinely observed in G1 prior to cell division commitment. Beyond this point, cells are presumed to complete S/G2/M at similar rates and in a size-independent manner. As such, studies of dependence between growth and division have focused on G1 Moreover, in unicellular organisms, coordination between growth and division has commonly been analysed within the cycle of a single cell without accounting for correlations in growth and division characteristics between cycles of related cells. In a comprehensive analysis of three published time-lapse microscopy datasets, we analyse both intra- and inter-cycle dependencies between growth and division, revisiting assumptions about the coordination between these two processes. Interestingly, we find evidence (i) that S/G2/M durations are systematically longer in daughters than in mothers, (ii) of dependencies between S/G2/M and size at budding that echo the classical G1 dependencies, and (iii) in contrast with recent bacterial studies, of negative dependencies between size at birth and size accumulated during the cell cycle. In addition, we develop a novel hierarchical model to uncover inter-cycle dependencies, and we find evidence for such dependencies in cells growing in sugar-poor environments. Our analysis highlights the need for experimentalists and modellers to account for new sources of cell-to-cell variation in growth and division, and our model provides a formal statistical framework for the continued study of dependencies between biological processes.


Assuntos
Ciclo Celular/fisiologia , Modelos Biológicos , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/citologia
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