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1.
Hum Mol Genet ; 32(14): 2292-2306, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37000013

RESUMO

Neurodegenerative diseases exhibiting the pathological accumulation of tau such as Alzheimer's disease and related disorders still have no disease-modifying treatments and the molecular mechanisms of neurodegeneration remain unclear. To discover additional suppressor of tauopathy (sut) genes that mediate or modulate the toxicity of pathological tau, we performed a classical genetic screen using a tau transgenic Caenorhabditis elegans model. From this screen, we identified the suppressing mutation W292X in sut-6, the C. elegans homolog of human NIPP1, which truncates the C-terminal RNA-binding domain. Using CRISPR-based genome editing approaches, we generated null and additional C-terminally truncated alleles in sut-6 and found that loss of sut-6 or sut-6(W292X) suppresses tau-induced behavioral locomotor deficits, tau protein accumulation and neuron loss. The sut-6(W292X) mutation showed stronger and semi-dominant suppression of tau toxicity while sut-6 deletion acted recessively. Neuronal overexpression of SUT-6 protein did not significantly alter tau toxicity, but neuronal overexpression of SUT-6 W292X mutant protein reduced tau-mediated deficits. Epistasis studies showed tauopathy suppression by sut-6 occurs independent of other known nuclear speckle-localized suppressors of tau such as sut-2, aly-1/aly-3 and spop-1. In summary, we have shown that sut-6/NIPP1 modulates tau toxicity and found a dominant mutation in the RNA-binding domain of sut-6 which strongly suppresses tau toxicity. This suggests that altering RNA-related functions of SUT-6/NIPP1 instead of complete loss of SUT-6/NIPP1 will provide the strongest suppression of tau.


Assuntos
Doença de Alzheimer , Proteínas de Caenorhabditis elegans , Tauopatias , Animais , Humanos , Proteínas tau/genética , Proteínas tau/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Tauopatias/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças
2.
Nature ; 575(7783): 512-518, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31597160

RESUMO

Liver cirrhosis is a major cause of death worldwide and is characterized by extensive fibrosis. There are currently no effective antifibrotic therapies available. To obtain a better understanding of the cellular and molecular mechanisms involved in disease pathogenesis and enable the discovery of therapeutic targets, here we profile the transcriptomes of more than 100,000 single human cells, yielding molecular definitions for non-parenchymal cell types that are found in healthy and cirrhotic human liver. We identify a scar-associated TREM2+CD9+ subpopulation of macrophages, which expands in liver fibrosis, differentiates from circulating monocytes and is pro-fibrogenic. We also define ACKR1+ and PLVAP+ endothelial cells that expand in cirrhosis, are topographically restricted to the fibrotic niche and enhance the transmigration of leucocytes. Multi-lineage modelling of ligand and receptor interactions between the scar-associated macrophages, endothelial cells and PDGFRα+ collagen-producing mesenchymal cells reveals intra-scar activity of several pro-fibrogenic pathways including TNFRSF12A, PDGFR and NOTCH signalling. Our work dissects unanticipated aspects of the cellular and molecular basis of human organ fibrosis at a single-cell level, and provides a conceptual framework for the discovery of rational therapeutic targets in liver cirrhosis.


Assuntos
Células Endoteliais/patologia , Cirrose Hepática/patologia , Fígado/patologia , Macrófagos/patologia , Análise de Célula Única , Animais , Estudos de Casos e Controles , Linhagem da Célula , Sistema do Grupo Sanguíneo Duffy/metabolismo , Células Endoteliais/metabolismo , Feminino , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/citologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/citologia , Cirrose Hepática/genética , Macrófagos/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Fenótipo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos/metabolismo , Tetraspanina 29/metabolismo , Transcriptoma , Migração Transendotelial e Transepitelial
3.
Phys Rev Lett ; 130(7): 076101, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36867795

RESUMO

Silicon (Si) exhibits a rich collection of phase transitions under ambient-temperature isothermal and shock compression. This report describes in situ diffraction measurements of ramp-compressed Si between 40 and 389 GPa. Angle-dispersive x-ray scattering reveals that Si assumes an hexagonal close-packed (hcp) structure between 40 and 93 GPa and, at higher pressure, a face-centered cubic structure that persists to at least 389 GPa, the highest pressure for which the crystal structure of Si has been investigated. The range of hcp stability extends to higher pressures and temperatures than predicted by theory.

4.
Phys Rev Lett ; 126(16): 162501, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33961478

RESUMO

We report the first measurement of the average of the electron-proton and positron-proton elastic scattering cross sections. This lepton charge-averaged cross section is insensitive to the leading effects of hard two-photon exchange, giving more robust access to the proton's electromagnetic form factors. The cross section was extracted from data taken by the OLYMPUS experiment at DESY, in which alternating stored electron and positron beams were scattered from a windowless gaseous hydrogen target. Elastic scattering events were identified from the coincident detection of the scattered lepton and recoil proton in a large-acceptance toroidal spectrometer. The luminosity was determined from the rates of Møller, Bhabha, and elastic scattering in forward electromagnetic calorimeters. The data provide some selectivity between existing form factor global fits and will provide valuable constraints to future fits.

5.
Phys Rev Lett ; 125(16): 165701, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33124844

RESUMO

Equation-of-state (pressure, density, temperature, internal energy) and reflectivity measurements on shock-compressed CO_{2} at and above the insulating-to-conducting transition reveal new insight into the chemistry of simple molecular systems in the warm-dense-matter regime. CO_{2} samples were precompressed in diamond-anvil cells to tune the initial densities from 1.35 g/cm^{3} (liquid) to 1.74 g/cm^{3} (solid) at room temperature and were then shock compressed up to 1 TPa and 93 000 K. Variation in initial density was leveraged to infer thermodynamic derivatives including specific heat and Gruneisen coefficient, exposing a complex bonded and moderately ionized state at the most extreme conditions studied.

6.
Atmos Environ (1994) ; 234: 117543-11753, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32601520

RESUMO

A photochemical model platform for Hawaii, Puerto Rico, and Virgin Islands predicting O3, PM2.5, and regional haze would be useful to support assessments relevant for the National Ambient Air Quality Standards (NAAQS), Regional Haze Rule, and the Prevention of Significant Deterioration (PSD) program. These areas have not traditionally been modeled with photochemical transport models, but a reasonable representation of meteorology, emissions (natural and anthropogenic), chemistry, and deposition could support air quality management decisions in these areas. Here, a prognostic meteorological model (Weather Research and Forecasting) and photochemical transport (Community Multiscale Air Quality) model were applied for the entire year of 2016 at 27, 9, and 3 km grid resolution for areas covering the Hawaiian Islands and Puerto Rico/Virgin Islands. Model predictions were compared against surface and upper air meteorological and chemical measurements available in both areas. The vertical gradient of temperature, humidity, and winds in the troposphere was well represented. Surface layer meteorological model performance was spatially variable, but temperature tended to be underestimated in Hawaii. Chemically speciated daily average PM2.5 was generally well characterized by the modeling system at urban and rural monitors in Hawaii and Puerto Rico/Virgin Islands. Model performance was notably impacted by the wildfire emission methodology. Model performance was mixed for hourly SO2, NO2, PM2.5, and CO and was often related to how well local emissions sources were characterized. SO2 predictions were much lower than measurements at monitors near active volcanos on Hawaii, which was expected since volcanic emissions were not included in these model simulations. Further research is needed to assess emission inventory representation of these areas and how microscale meteorology influenced by the complex land-water and terrain interfaces impacts higher time resolution performance.

8.
Int J Obes (Lond) ; 41(2): 324-331, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27867202

RESUMO

BACKGROUND/OBJECTIVES: Central adiposity measures such as waist circumference (WC) and waist-to-hip ratio (WHR) are associated with cardiometabolic disorders independently of body mass index (BMI) and are gaining clinically utility. Several studies report genetic variants associated with central adiposity, but most utilize only European ancestry populations. Understanding whether the genetic associations discovered among mainly European descendants are shared with African ancestry populations will help elucidate the biological underpinnings of abdominal fat deposition. SUBJECTS/METHODS: To identify the underlying functional genetic determinants of body fat distribution, we conducted an array-wide association meta-analysis among persons of African ancestry across seven studies/consortia participating in the Population Architecture using Genomics and Epidemiology (PAGE) consortium. We used the Metabochip array, designed for fine-mapping cardiovascular-associated loci, to explore novel array-wide associations with WC and WHR among 15 945 African descendants using all and sex-stratified groups. We further interrogated 17 known WHR regions for African ancestry-specific variants. RESULTS: Of the 17 WHR loci, eight single-nucleotide polymorphisms (SNPs) located in four loci were replicated in the sex-combined or sex-stratified meta-analyses. Two of these eight independently associated with WHR after conditioning on the known variant in European descendants (rs12096179 in TBX15-WARS2 and rs2059092 in ADAMTS9). In the fine-mapping assessment, the putative functional region was reduced across all four loci but to varying degrees (average 40% drop in number of putative SNPs and 20% drop in genomic region). Similar to previous studies, the significant SNPs in the female-stratified analysis were stronger than the significant SNPs from the sex-combined analysis. No novel associations were detected in the array-wide analyses. CONCLUSIONS: Of 17 previously identified loci, four loci replicated in the African ancestry populations of this study. Utilizing different linkage disequilibrium patterns observed between European and African ancestries, we narrowed the suggestive region containing causative variants for all four loci.


Assuntos
Adiposidade/genética , População Negra/genética , Variação Genética , População Branca/genética , Adulto , Distribuição da Gordura Corporal , Feminino , Predisposição Genética para Doença/etnologia , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Obesidade Abdominal/etnologia , Obesidade Abdominal/genética , Polimorfismo de Nucleotídeo Único/genética , Relação Cintura-Quadril
9.
Phys Rev Lett ; 119(17): 175702, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29219452

RESUMO

Nanosecond in situ x-ray diffraction and simultaneous velocimetry measurements were used to determine the crystal structure and pressure, respectively, of ramp-compressed aluminum at stress states between 111 and 475 GPa. The solid-solid Al phase transformations, fcc-hcp and hcp-bcc, are observed at 216±9 and 321±12 GPa, respectively, with the bcc phase persisting to 475 GPa. The high-pressure crystallographic texture of the hcp and bcc phases suggests close-packed or nearly close-packed lattice planes remain parallel through both transformations.

10.
Phys Rev Lett ; 118(9): 092501, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28306315

RESUMO

The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20° to 80°. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved gas electron multiplier and multiwire proportional chamber detectors at 12°, as well as symmetric Møller or Bhabha calorimeters at 1.29°. A total integrated luminosity of 4.5 fb^{-1} was collected. In the extraction of R_{2γ}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R_{2γ}, presented here for a wide range of virtual photon polarization 0.456<ε<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.

11.
Rev Sci Tech ; 35(2): 417-433, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27917982

RESUMO

The authors discuss the main climate change impacts on pastoralist societies, including those on rangelands, livestock and other natural resources, and their extended repercussions on food security, incomes and vulnerability. The impacts of climate change on the rangelands of the globe and on the vulnerability of the people who inhabit them will be severe and diverse, and will require multiple, simultaneous responses. In higher latitudes, the removal of temperature constraints might increase pasture production and livestock productivity, but in tropical arid lands, the impacts are highly location specific, but mostly negative. The authors outline several adaptation options, ranging from implementing new technical practices and diversifying income sources to finding institutional support and introducing new market mechanisms, all of which are pivotal for enhancing the capacity of pastoralists to adapt to climate variability and change. Due to the dynamism of all the changes affecting pastoral societies, strategies that lock pastoral societies into specified development pathways could be maladaptive. Flexible and evolving combinations of practices and policies are the key to successful pastoral adaptation.


Les auteurs examinent les principaux effets du changement climatique sur les sociétés pastorales, en particulier ceux qui affectent les prairies, le bétail et d'autres ressources naturelles ainsi que les répercussions durables sur la sécurité alimentaire, sur les revenus et sur la vulnérabilité des populations. Le changement climatique va profondément et diversement affecter les prairies de la planète et le degré de vulnérabilité des personnes qui y vivent, ce qui imposera de déployer des réponses multiples et simultanées. Si dans les latitudes plus élevées, la suppression de certaines contraintes liées aux températures permet d'augmenter la production d'herbage et d'accroître la productivité du bétail, dans les terres arides tropicales les effets du climat, très spécifiques selon les endroits, sont majoritairement négatifs. Les diverses solutions adaptatives mises en avant par les auteurs, depuis la mise en oeuvre de nouvelles techniques et la diversification des sources de revenus jusqu'à la recherche de soutiens institutionnels et la création de nouveaux mécanismes de marché, sont toutes déterminantes pour améliorer la capacité des pasteurs à s'adapter à la variabilité et au changement climatiques. En raison du caractère dynamique des changements affectant les sociétés pastorales, les stratégies consistant à confiner ces sociétés dans des tracés spécifiques de développement risquent de s'avérer contreproductives en termes d'adaptation. Un assortiment souple et évolutif de pratiques et de politiques est la clé d'une adaptation pastorale réussie.


Los autores examinan los principales efectos del cambio climático sobre las sociedades pastorales, en particular los que afectan a las tierras de pasto, el ganado y otros recursos naturales, así como sus repercusiones más indirectas sobre la seguridad alimentaria, los ingresos y la vulnerabilidad. El cambio climático traerá consigo diversos efectos de gravedad que influirán en los pastizales del planeta y la vulnerabilidad de quienes viven de ellos, efectos que exigirán múltiples respuestas simultáneas. En altas latitudes, la desaparición de las limitaciones ligadas a la temperatura podría deparar una mayor producción de los pastizales y con ello una mayor productividad del ganado, pero en las tierras áridas tropicales los efectos dependerán en gran medida de las condiciones de cada localidad y serán mayormente negativos. Los autores destacan varias posibilidades de adaptación, desde la aplicación de nuevos procedimientos técnicos y la diversificación de las fuentes de ingresos hasta la obtención de apoyo institucional, pasando por la instauración de nuevos mecanismos de mercado, todas ellas soluciones cruciales para dotar a las sociedades de pastores de mayor capacidad de adaptación a la variabilidad y la evolución del clima. Teniendo en cuenta el dinamismo de cuantos cambios afectan a las sociedades pastorales, toda estrategia que las encorsete en una u otra vía específica de desarrollo podría resultar inadaptada. La clave para una adaptación fructífera de esas sociedades estriba en combinaciones de prácticas y políticas que sean flexibles y evolucionen en el tiempo.


Assuntos
Adaptação Biológica , Criação de Animais Domésticos/métodos , Mudança Climática , Criação de Animais Domésticos/tendências , Animais , Humanos , Conhecimento , Marketing , Apoio Social , Tecnologia
12.
Clin Oral Investig ; 20(9): 2559-2564, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26961374

RESUMO

BACKGROUND AND OBJECTIVE: Microbial recognition in the periodontium through specific leukocyte receptors gives rise to the response which in susceptible individuals can lead to periodontal diseases. The aim of this study was to explore the expression of leukocyte receptors in the gingival tissues of chronic periodontitis patients and to analyse differences between diseased and control sites (sites with probing pocket depth <4 mm). MATERIAL AND METHODS: Thirty-seven chronic periodontitis patients were included in the study. Gingival biopsies were harvested from diseased and control sites and processed by flow cytometry for the determination of the expression of 16 leukocyte receptors (CD4, CD8, CD11b, CD14, CD16, CD19, CD25, CD28, CD49d, CD49e, CD62, CD71, CD80, CCR7, Ly6G and HLA-DR). RESULTS: Expression of all studied receptors was higher in test compared with control sites (p < 0.005). Sampled sites with less bleeding on probing exhibited higher expression of CD16 and CD14 receptors (p = 0.020 and 0.011, respectively). CONCLUSIONS: This study points towards considerable differences in the expression of leukocyte receptors between diseased and control sites in the same periodontal patients.


Assuntos
Periodontite Crônica/imunologia , Receptores de Adesão de Leucócito/imunologia , Adulto , Idoso , Biópsia , Periodontite Crônica/microbiologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal
13.
Agric Syst ; 143: 106-113, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26941474

RESUMO

In this study we estimate yield gaps for mixed crop-livestock smallholder farmers in seven Sub-Saharan African sites covering six countries (Kenya, Tanzania, Uganda, Ethiopia, Senegal and Burkina Faso). We also assess their potential to increase food production and reduce the GHG emission intensity of their products, as a result of closing these yield gaps. We use stochastic frontier analysis to construct separate production frontiers for each site, based on 2012 survey data prepared by the International Livestock Research Institute for the Climate Change, Agriculture and Food Security program. Instead of relying on theoretically optimal yields-a common approach in yield gap assessments-our yield gaps are based on observed differences in technical efficiency among farms within each site. Sizeable yield gaps were estimated to be present in all of the sites. Expressed as potential percentage increases in outputs, the average site-based yield gaps ranged from 28 to 167% for livestock products and from 16 to 209% for crop products. The emission intensities of both livestock and crop products registered substantial falls as a consequence of closing yield gaps. The relationships between farm attributes and technical efficiency were also assessed to help inform policy makers about where best to target capacity building efforts. We found a strong and statistically significant relationship between market participation and performance across most sites. We also identified an efficiency dividend associated with the closer integration of crop and livestock enterprises. Overall, this study reveals that there are large yield gaps and that substantial benefits for food production and environmental performance are possible through closing these gaps, without the need for new technology.

14.
Breast Cancer Res Treat ; 144(1): 171-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24481681

RESUMO

Sequence-based testing of disease-susceptibility genes has identified many variants of unknown significance (VUSs) whose pathogenicity is unknown at the time of their measurement. Female breast cancer cases aged 20-49 years at diagnosis and who have VUSs in BRCA1 and no mutations in BRCA2 have previously been identified through the population-based Los Angeles County Cancer Surveillance Program. These nominal BRCA1 VUSs have been classified as "low," "medium," and "high" risk by four classification methods: Align-GVGD, Polyphen, Grantham matrix scores, and sequence conservation in mammalian species. Average hazard ratios (HRs) for classes of variants, i.e., the age-specific incidences of cancer for carriers of such variants divided by the population incidences, were estimated from the cancer family histories of first- and second-degree relatives of the index cases using modified segregation analysis. The study sample comprised 270 index cases and 4,543 of their relatives. There was weak evidence that the risk of breast cancer increases with the degree of sequence conservation (P = 0.03) and that missense variants at highly conserved sites are associated with a 5.6-fold (95 % confidence interval 1.4-22.2; P = 0.05) increased incidence of breast cancer. An upper bound of 2.3 is given for the average breast cancer HRs corresponding to variants classified as "low risk" by any of the four VUS classification methods. In summary, we have given a method to estimate cancer risks for groups of VUSs by combining existing classification methods with traditional penetrance analyses. This analysis suggests that classification methods for BRCA1 variants based on sequence conservation might be useful in a clinical setting. We have shown in principle that our method can be used to classify VUSs into clinically useful risk categories, but our specific findings should not be put into clinical practice unless confirmed by larger studies.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Predisposição Genética para Doença/genética , Adulto , Sequência Conservada/genética , Feminino , Variação Genética , Humanos , Pessoa de Meia-Idade , Risco , Adulto Jovem
15.
Int J Obes (Lond) ; 38(11): 1416-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24522245

RESUMO

BACKGROUND: Ethnic disparities in metabolic disease risk may be the result of differences in circulating adipokines and inflammatory markers related to ethnic variations in obesity and body fat distribution. SUBJECTS/METHODS: In a cross-sectional design, we compared serum levels of leptin, adiponectin, C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in control subjects (321 men and 930 women) from two nested case-control studies conducted within the Multiethnic Cohort Study consisting of whites, Japanese Americans (JA), Latinos, African Americans (AA) and Native Hawaiians (NH). General linear models were applied to evaluate ethnic differences in log-transformed serum biomarker levels before and after adjusting for body mass index (BMI) at cohort entry. RESULTS: In comparison to whites, significant ethnic differences were observed for all biomarkers except TNF-α. JA men and women had significantly lower leptin and CRP levels than whites, and JA women also had lower adiponectin levels. Leptin was significantly higher in AA women (P < 0.01), adiponectin was significantly lower in AA men and women (P = 0.02 and P < 0.001), and CRP and IL-6 were significantly higher in AA men and women. Lower adiponectin (P < 0.0001) and CRP (P = 0.03) levels were the only biomarkers in NH women that differed from whites; no statistically significant differences were seen for NH men and for Latino men and women. When adjusted for BMI at cohort entry, the differences between the lowest and the highest values across ethnic groups decreased for all biomarkers except adiponectin in men indicating that ethnic differences were partially due to weight status. CONCLUSIONS: These findings demonstrate the ethnic variations in circulating adipokine and CRP levels before and after adjustment for BMI. Given the limitation of BMI as a general measure of obesity, further investigation with visceral and subcutaneous adiposity measures are warranted to elucidate ethnicity-related differences in adiposity in relation to disparities in obesity-related disease risk.


Assuntos
Adipocinas/sangue , Proteína C-Reativa/metabolismo , Obesidade/sangue , Grupos Raciais/estatística & dados numéricos , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Asiático/estatística & dados numéricos , Biomarcadores/sangue , Distribuição da Gordura Corporal , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Havaí/etnologia , Disparidades nos Níveis de Saúde , Hispânico ou Latino/estatística & dados numéricos , Humanos , Interleucina-6/sangue , Leptina/sangue , Masculino , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Obesidade/epidemiologia , Obesidade/etnologia , Fator de Necrose Tumoral alfa/sangue , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos
16.
Nat Rev Cancer ; 5(12): 977-85, 2005 12.
Artigo em Inglês | MEDLINE | ID: mdl-16341085

RESUMO

Most cases of breast and prostate cancer are not associated with mutations in known high-penetrance genes, indicating the involvement of multiple low-penetrance risk alleles. Studies that have attempted to identify these genes have met with limited success. The National Cancer Institute Breast and Prostate Cancer Cohort Consortium--a pooled analysis of multiple large cohort studies with a total of more than 5,000 cases of breast cancer and 8,000 cases of prostate cancer--was therefore initiated. The goal of this consortium is to characterize variations in approximately 50 genes that mediate two pathways that are associated with these cancers--the steroid-hormone metabolism pathway and the insulin-like growth factor signalling pathway--and to associate these variations with cancer risk.


Assuntos
Neoplasias da Mama/genética , Genes Neoplásicos , Penetrância , Neoplasias da Próstata/genética , Neoplasias da Mama/metabolismo , Estudos de Coortes , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Neoplasias da Próstata/metabolismo
17.
Br J Cancer ; 108(3): 727-34, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23348519

RESUMO

BACKGROUND: Uterine sarcomas are characterised by early age at diagnosis, poor prognosis, and higher incidence among Black compared with White women, but their aetiology is poorly understood. Therefore, we performed a pooled analysis of data collected in the Epidemiology of Endometrial Cancer Consortium. We also examined risk factor associations for malignant mixed mullerian tumours (MMMTs) and endometrioid endometrial carcinomas (EECs) for comparison purposes. METHODS: We pooled data on 229 uterine sarcomas, 244 MMMTs, 7623 EEC cases, and 28,829 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) for risk factors associated with uterine sarcoma, MMMT, and EEC were estimated with polytomous logistic regression. We also examined associations between epidemiological factors and histological subtypes of uterine sarcoma. RESULTS: Significant risk factors for uterine sarcoma included obesity (body mass index (BMI)≥30 vs BMI<25 kg m(-2) (OR: 1.73, 95% CI: 1.22-2.46), P-trend=0.008) and history of diabetes (OR: 2.33, 95% CI: 1.41-3.83). Older age at menarche was inversely associated with uterine sarcoma risk (≥15 years vs <11 years (OR: 0.70, 95% CI: 0.34-1.44), P-trend: 0.04). BMI was significantly, but less strongly related to uterine sarcomas compared with EECs (OR: 3.03, 95% CI: 2.82-3.26) or MMMTs (OR: 2.25, 95% CI: 1.60-3.15, P-heterogeneity=0.01). CONCLUSION: In the largest aetiological study of uterine sarcomas, associations between menstrual, hormonal, and anthropometric risk factors and uterine sarcoma were similar to those identified for EEC. Further exploration of factors that might explain patterns of age- and race-specific incidence rates for uterine sarcoma are needed.


Assuntos
Neoplasias do Endométrio/etiologia , Tumor Mulleriano Misto/etiologia , Sarcoma/etiologia , Neoplasias Uterinas/etiologia , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Neoplasias do Endométrio/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Tumor Mulleriano Misto/epidemiologia , Obesidade/complicações , Prognóstico , Fatores de Risco , Sarcoma/epidemiologia , Estados Unidos/epidemiologia , Neoplasias Uterinas/epidemiologia
18.
Hum Reprod ; 28(6): 1695-706, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23508249

RESUMO

STUDY QUESTION: Do genetic associations identified in genome-wide association studies (GWAS) of age at menarche (AM) and age at natural menopause (ANM) replicate in women of diverse race/ancestry from the Population Architecture using Genomics and Epidemiology (PAGE) Study? SUMMARY ANSWER: We replicated GWAS reproductive trait single nucleotide polymorphisms (SNPs) in our European descent population and found that many SNPs were also associated with AM and ANM in populations of diverse ancestry. WHAT IS KNOWN ALREADY: Menarche and menopause mark the reproductive lifespan in women and are important risk factors for chronic diseases including obesity, cardiovascular disease and cancer. Both events are believed to be influenced by environmental and genetic factors, and vary in populations differing by genetic ancestry and geography. Most genetic variants associated with these traits have been identified in GWAS of European-descent populations. STUDY DESIGN, SIZE, DURATION: A total of 42 251 women of diverse ancestry from PAGE were included in cross-sectional analyses of AM and ANM. MATERIALS, SETTING, METHODS: SNPs previously associated with ANM (n = 5 SNPs) and AM (n = 3 SNPs) in GWAS were genotyped in American Indians, African Americans, Asians, European Americans, Hispanics and Native Hawaiians. To test SNP associations with ANM or AM, we used linear regression models stratified by race/ethnicity and PAGE sub-study. Results were then combined in race-specific fixed effect meta-analyses for each outcome. For replication and generalization analyses, significance was defined at P < 0.01 for ANM analyses and P < 0.017 for AM analyses. MAIN RESULTS AND THE ROLE OF CHANCE: We replicated findings for AM SNPs in the LIN28B locus and an intergenic region on 9q31 in European Americans. The LIN28B SNPs (rs314277 and rs314280) were also significantly associated with AM in Asians, but not in other race/ethnicity groups. Linkage disequilibrium (LD) patterns at this locus varied widely among the ancestral groups. With the exception of an intergenic SNP at 13q34, all ANM SNPs replicated in European Americans. Three were significantly associated with ANM in other race/ethnicity populations: rs2153157 (6p24.2/SYCP2L), rs365132 (5q35/UIMC1) and rs16991615 (20p12.3/MCM8). While rs1172822 (19q13/BRSK1) was not significant in the populations of non-European descent, effect sizes showed similar trends. LIMITATIONS, REASONS FOR CAUTION: Lack of association for the GWAS SNPs in the non-European American groups may be due to differences in locus LD patterns between these groups and the European-descent populations included in the GWAS discovery studies; and in some cases, lower power may also contribute to non-significant findings. WIDER IMPLICATIONS OF THE FINDINGS: The discovery of genetic variants associated with the reproductive traits provides an important opportunity to elucidate the biological mechanisms involved with normal variation and disorders of menarche and menopause. In this study we replicated most, but not all reported SNPs in European descent populations and examined the epidemiologic architecture of these early reported variants, describing their generalizability and effect size across differing ancestral populations. Such data will be increasingly important for prioritizing GWAS SNPs for follow-up in fine-mapping and resequencing studies, as well as in translational research.


Assuntos
Menarca/genética , Menopausa/genética , Polimorfismo de Nucleotídeo Único , Fatores Etários , Estudos Transversais , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Menarca/etnologia , Menopausa/etnologia
19.
Br J Cancer ; 107(9): 1534-46, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-22996613

RESUMO

BACKGROUND: Photodynamic therapy (PDT) causes tissue damage that initiates a local inflammatory response. Post-PDT reactions are considered to assist in mobilising the immune system thereby affecting tumour recurrence. The initiating process of the PDT-dependent tissue reaction remains to be determined. METHODS: Primary cultures of human lung cells were established. The photoreaction mediated by pyropheophorbide-a, at specific subcellular sites and levels resulting in the release of alarmins by epithelial cells (Eps), was defined by immunoblot analyses and expression profiling. The activity of Ep-derived factors to stimulate expression of proinflammatory mediators, including IL-6, and to enhance neutrophil binding by fibroblasts (Fbs) was determined by functional bioassays. RESULTS: Epithelial cells release IL-1ß as the primary Fb-stimulatory activity under basal conditions. Intracellular IL-1α, externalised following photoreaction, accounts for most of the PDT-mediated Fb activation. Expression of IL-1 is subject to increase or loss during oncogenic transformation resulting in altered alarmin functions mobilisable by PDT. Photoreaction by a cell surface-bound photosensitiser (PS) is 10-fold more effective than PSs localised to mitochondria or lysosomes. High-dose intracellular, but not cell surface, photoreaction inactivates IL-1 and reduces Fb stimulation. CONCLUSION: These in vitro data suggest that the subcellular site and intensity of photoreaction influence the magnitude of the stromal cell response to the local damage and, in part, support the relationship of PDT dose and level of post-PDT inflammatory response observed in vivo.


Assuntos
Mediadores da Inflamação/metabolismo , Interleucina-1alfa/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Fotoquimioterapia/métodos , Animais , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Pulmão/citologia , Ratos
20.
J Intern Med ; 271(4): 353-65, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22308973

RESUMO

Prostate cancer is the commonest cancer in the developed world. There is an inherited component to this disease as shown in familial and twin studies. However, the discovery of these variants has been difficult. The emergence of genome-wide association studies has led to the identification of over 46 susceptibility loci. Their clinical utility to predict risk, response to treatment, or treatment toxicity, remains undefined. Large consortia are needed to achieve adequate statistical power to answer these genetic-clinical and genetic-epidemiological questions. International collaborations are currently underway to link genetic with clinical/epidemiological data to develop risk prediction models, which could direct screening and treatment programs.


Assuntos
Predisposição Genética para Doença , Neoplasias da Próstata/genética , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Cooperação Internacional , Masculino , Polimorfismo de Nucleotídeo Único , Prostatectomia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/prevenção & controle , Neoplasias da Próstata/terapia
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