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INTRODUCTION: Although most invasive cervical cancer (ICC) harbor <20 human papillomavirus (HPV) genotypes, use of HPV screening to predict ICC from HPV has low specificity, resulting in multiple and costly follow-up visits and overtreatment. We examined DNA methylation at regulatory regions of imprinted genes in relation to ICC and its precursor lesions to determine if methylation profiles are associated with progression of HPV-positive lesions to ICC. MATERIALS AND METHODS: We enrolled 148 controls, 38 CIN and 48 ICC cases at Kilimanjaro Christian Medical Centre from 2008 to 2009. HPV was genotyped by linear array and HIV-1 serostatus was tested by two rapid HIV tests. DNA methylation was measured by bisulfite pyrosequencing at regions regulating eight imprinted domains. Logistic regression models were used to estimate odd ratios. RESULTS: After adjusting for age, HPV infection, parity, hormonal contraceptive use, and HIV-1 serostatus, a 10 % decrease in methylation levels at an intragenic region of IGF2 was associated with higher risk of ICC (OR 2.00, 95 % CI 1.14-3.44) and cervical intraepithelial neoplasia (CIN) (OR 1.51, 95 % CI 1.00-2.50). Methylation levels at the H19 DMR and PEG1/MEST were also associated with ICC risk (OR 1.51, 95 % CI 0.90-2.53, and OR 1.44, 95 % CI 0.90-2.35, respectively). Restricting analyses to women >30 years further strengthened these associations. CONCLUSIONS: While the small sample size limits inference, these findings show that altered DNA methylation at imprinted domains including IGF2/H19 and PEG1/MEST may mediate the association between HPV and ICC risk.
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Metilação de DNA , Fator de Crescimento Insulin-Like II/genética , Infecções por Papillomavirus/complicações , Proteínas/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/virologiaRESUMO
We report observation of the electroweak production of single top quarks in pp[over ] collisions at sqrt[s]=1.96 TeV based on 2.3 fb(-1) of data collected by the D0 detector at the Fermilab Tevatron Collider. Using events containing an isolated electron or muon and missing transverse energy, together with jets originating from the fragmentation of b quarks, we measure a cross section of sigma(pp[over ]--> tb + X, tqb + X) = 3.94 + or - 0.88 pb. The probability to measure a cross section at this value or higher in the absence of signal is 2.5 x 10(-7), corresponding to a 5.0 standard deviation significance for the observation.
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We present a search for a narrow resonance in the inclusive diphoton final state using approximately 2.7 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron pp Collider. We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.
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We present a search for direct CP violation in B(+/-)-->J/psiK(+/-)(pi(+/-)) decays. The event sample is selected from 2.8 fb(-1) of pp collisions recorded by D0 experiment in run II of the Fermilab Tevatron Collider. The charge asymmetry A_(CP)(B(+)-->J/psiK(+))= + 0.0075 +/- 0.0061(stat)+/-0.0030(syst) is obtained using a sample of approximately 40, 000 B(+/-)-->J/psiK(+/-) decays. The achieved precision is of the same level as the expected deviation predicted by some extensions of the standard model. We also measured the charge asymmetry A(CP)(B(+)-->J/psipi(+))=-0.09+/-0.08(stat)+/-0.03(syst).
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We search for the production of a heavy W' gauge boson that decays to third generation quarks in 0.9 fb-1 of pp collisions at square root(s)=1.96 TeV, collected with the D0 detector at the Fermilab Tevatron collider. We find no significant excess in the final-state invariant mass distribution and set upper limits on the production cross section times branching fraction. For a left-handed W' boson with SM couplings, we set a lower mass limit of 731 GeV. For right-handed W' bosons, we set lower mass limits of 739 GeV if the W' boson decays to both leptons and quarks and 768 GeV if the W' boson decays only to quarks. We also set limits on the coupling of the W' boson to fermions as a function of its mass.
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We present a search for associated Higgs boson production in the process pp-->WH-->WWW*-->l;+/-nul'+/-nu'+X in final states containing two like-sign isolated electrons or muons (e+/-e;+/-, e+/-micro+/-, or micro+/-micro+/-). The search is based on D0 run II data samples corresponding to integrated luminosities of 360-380 pb-1. No excess is observed over the predicted standard model background. We set 95% C.L. upper limits on sigma(pp-->WH)xBr(H-->WW*) between 3.2 and 2.8 pb for Higgs boson masses from 115 to 175 GeV.
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A search for associated production of charginos and neutralinos is performed using data recorded with the D0 detector at a pp center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. This analysis considers final states with missing transverse energy and three charged leptons, of which at least two are electrons or muons. No evidence for supersymmetry is found in a data set corresponding to an integrated luminosity of 320 pb-1. Limits on the product of the production cross section and leptonic branching fraction are set. For the minimal supergravity model, a chargino lower mass limit of 117 GeV at the 95% C.L. is derived in regions of parameter space with enhanced leptonic branching fractions.
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We have performed a search for neutral Higgs bosons produced in association with bottom quarks in pp collisions, using 260 pb-1 of data collected with the D0 detector in Run II of the Fermilab Tevatron Collider. The cross sections for these processes are enhanced in many extensions of the standard model (SM), such as in its minimal supersymmetric extension at large tanbeta. The results of our analysis agree with expectations from the SM, and we use our measurements to set upper limits on the production of neutral Higgs bosons in the mass range of 90 to 150 GeV.
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The recent bioengineering of complex tooth structures from pig tooth bud tissues suggests the potential for the regeneration of mammalian dental tissues. We have improved tooth bioengineering methods by comparing the utility of cultured rat tooth bud cells obtained from three- to seven-day post-natal (dpn) rats for tooth-tissue-engineering applications. Cell-seeded biodegradable scaffolds were grown in the omenta of adult rat hosts for 12 wks, then harvested. Analyses of 12-week implant tissues demonstrated that dissociated 4-dpn rat tooth bud cells seeded for 1 hr onto PGA or PLGA scaffolds generated bioengineered tooth tissues most reliably. We conclude that tooth-tissue-engineering methods can be used to generate both pig and rat tooth tissues. Furthermore, our ability to bioengineer tooth structures from cultured tooth bud cells suggests that dental epithelial and mesenchymal stem cells can be maintained in vitro for at least 6 days.
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Implantes Absorvíveis , Odontogênese/fisiologia , Engenharia Tecidual/métodos , Germe de Dente/crescimento & desenvolvimento , Dente/crescimento & desenvolvimento , Fatores Etários , Animais , Materiais Biocompatíveis/química , Diferenciação Celular , Ácido Láctico/química , Membranas Artificiais , Omento/cirurgia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/química , Ratos , Ratos Endogâmicos Lew , Células-Tronco/citologia , Células-Tronco/fisiologia , Dente/citologia , Dente/transplante , Germe de Dente/citologia , Germe de Dente/transplanteRESUMO
The D0 Collaboration has measured the inclusive jet cross section in barpp collisions at square root of s = 630 GeV. The results for pseudorapidities (eta)<0.5 are combined with our previous results at square root of s = 1800 GeV to form a ratio of cross sections with smaller uncertainties than either individual measurement. Next-to-leading-order QCD predictions show excellent agreement with the measurement at 630 GeV; agreement is also satisfactory for the ratio. Specifically, despite a 10% to 15% difference in the absolute magnitude, the dependence of the ratio on jet transverse momentum is very similar for data and theory.
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We report a search for effects of large extra spatial dimensions in pp collisions at a center-of-mass energy of 1.8 TeV with the D0 detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions.
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To establish the frequency of necrotizing funisitis in congenital syphilis, we conducted a prospective descriptive study of maternal syphilis in Bolivia by testing 1,559 women at delivery with rapid plasma reagin (RPR). We examined umbilical cords of 66 infants whose mothers had positive RPR and fluorescent treponemal antibody absorption tests. Histologic abnormalities were detected in 28 (42%) umbilical cords (seven [11%] had necrotizing funisitis with spirochetes; three [4%] had marked funisitis without necrosis; and 18 [27%] had mild funisitis), and 38 [58%] were normal. Of 22 umbilical cords of infants from mothers without syphilis (controls), only two (9%) showed mild funisitis; the others were normal. Testing umbilical cords by using immunohistochemistry is a research tool that can establish the frequency of funisitis due to Treponema pallidum infection.
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Sífilis/diagnóstico , Treponema pallidum/isolamento & purificação , Cordão Umbilical/patologia , Anticorpos Antibacterianos/isolamento & purificação , Bolívia/epidemiologia , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Necrose , Estudos Prospectivos , Sífilis/epidemiologia , Cordão Umbilical/anormalidades , Cordão Umbilical/microbiologiaRESUMO
The effectiveness of two educational intervention programmes in promoting infant feeding practices was assessed among mothers of small children attending a hospital's Oral Rehydration Unit in Peru. One group of mothers received 5 min of counselling and a recipe pamphlet. The other group received the same counselling plus a 20-min cooking demonstration. Both interventions had a statistically significant (p < 0.05) impact on maternal knowledge and practices; differences between the impact of the two practices were negligible. After merging both groups into a single sample, it was observed that changes over time were significantly large (p < 0.05). Knowledge rates were 27.6% before the intervention, 73.7% 2 days later and 75% 30 days later. The corresponding figures for practices were 2.6%, 58.3% and 37.5% respectively. We conclude that when place, time and message are adequately chosen, a simple method may be an effective way of good communication. We suggest that a larger implementation trial would be useful before starting larger infant feeding programmes.
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Diarreia/dietoterapia , Fenômenos Fisiológicos da Nutrição do Lactente , Aconselhamento , Diarreia/epidemiologia , Humanos , Lactente , Peru/epidemiologia , DesmameRESUMO
Three hundred thirty-nine migrant worker women and children were screened by single stool examination for intestinal parasites. Infection occurred in 34.2%. Giardia lamblia and Trichuris trichiura were the most common pathogens; Entamoeba coli and Endolimax nana were the most common commensals. Infants under 1 year of age were free of infection. Children between 2 and 5 years old and women between 25 and 35 years old had the highest prevalence. Significantly more Haitians were infected than Mexican-Americans or American blacks. Of ten symptoms, only abdominal pain and gas correlated significantly with infection. This migrant population has a greater prevalence of intestinal parasites than the general American public. Screening by stool examination may be beneficial to diminish the reservoir of infection.