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1.
Nature ; 575(7783): 459-463, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31748725

RESUMO

Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission1,2. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands1-6. The afterglow emission is generally well explained as synchrotron radiation emitted by electrons accelerated by the external shock7-9. Recently, intense long-lasting emission between 0.2 and 1 teraelectronvolts was observed from GRB 190114C10,11. Here we report multi-frequency observations of GRB 190114C, and study the evolution in time of the GRB emission across 17 orders of magnitude in energy, from 5 × 10-6 to 1012 electronvolts. We find that the broadband spectral energy distribution is double-peaked, with the teraelectronvolt emission constituting a distinct spectral component with power comparable to the synchrotron component. This component is associated with the afterglow and is satisfactorily explained by inverse Compton up-scattering of synchrotron photons by high-energy electrons. We find that the conditions required to account for the observed teraelectronvolt component are typical for GRBs, supporting the possibility that inverse Compton emission is commonly produced in GRBs.

2.
J Eur Acad Dermatol Venereol ; 34(9): 2051-2058, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32027420

RESUMO

INTRODUCTION: The National Psoriasis Foundation (NPF) published treat-to-target guidelines for psoriasis, yet their applicability in clinical practice remains unknown. OBJECTIVES: To estimate the proportion of psoriasis patients meeting the NPF's body surface area (BSA) 'target' (≤1%) and 'acceptable' (≤3%) response criteria and the cross-sectional associations of these criteria with patient-reported outcomes (PROs) in the Corrona Psoriasis Registry. METHODS: Separately for three independent cross-sectional cohorts of patients at the (i) enrolment, (ii) 6-month and (iii) 12-month visits, we calculated the proportion of patients with BSA ≤1% and ≤3%. Furthermore, we calculated odds ratios estimating the risk of PROs associated with not meeting criteria in the 6-month cohort. RESULTS: The enrolment, 6- and 12-month cohorts included 2794, 1310 and 629 patients, respectively. At enrolment, 24% of patients had a BSA ≤ 1% and 41% a BSA ≤ 3%. In the 6-month cohort, 43%/64% had a BSA ≤ 1%/BSA ≤ 3%. In the 12-month cohort, 46%/69% of patients had a BSA ≤ 1%/BSA ≤ 3%. Patients not at target/acceptable criteria had higher odds for worse quality of life compared with those who were. CONCLUSION: While most patients at 6- and 12-month visits were at the 'acceptable' response, less than half were at the 'target' response despite systemic therapy. There remain unmet needs to optimize psoriasis therapy and further validate current treat-to-target guidelines.


Assuntos
Psoríase , Qualidade de Vida , Estudos Transversais , Humanos , Medidas de Resultados Relatados pelo Paciente , Prevalência , Psoríase/tratamento farmacológico , Psoríase/epidemiologia , Sistema de Registros , Índice de Gravidade de Doença
3.
Public Health ; 158: 183-197, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29653867

RESUMO

OBJECTIVE: The objective of this article is to investigate the link between migration and knowledge and use of birth control methods among female household members (of migrants) who stay behind in Afghanistan. Migrants can remit birth control information received in the destination country to non-migrants staying in the origin country, who may as a consequence adjust their health behaviour accordingly. The consequences of this interaction for knowledge and use are what we aim to test. STUDY DESIGN: Population-based secondary analysis of cross-sectional data. METHODS: This study used cross-sectional data from the Afghan Mortality Survey (2010). Using ordinary least squares regression and propensity score matching, this research studies to what extent having a migrant in the household influences the knowledge and use of birth control among non-migrant Afghan women. Women who stay behind are defined in this research as those with a migrant household member who moved between 2005 and 2010. RESULTS: Results indicated that non-Pashtun women with a migrant household member showed greater knowledge of contraceptive methods using injectables, birth control pill and lactational amenorrhea method compared to those women without a migrant household member. Less knowledge of male sterilisation and emergency contraception is observed for all women (both Pashtun and non-Pashtun) with a migrant in their household on male sterilisation and emergency contraception compared to the women without a migrant in the household. In addition, we show that Pashtun women with a migrant in the household had lower levels of overall knowledge and were less likely to use birth control methods than women without a migrant household member. CONCLUSION: In Afghanistan, given the proximity, religious similarity and sociocultural customs mainly men migrate either to Pakistan or Iran. The findings suggest that migrants in different destination countries transfer different information (or fail to successfully transfer information) about birth control methods to members of their transnational networks, compounding disparities in knowledge and use of birth control methods among women staying in the origin country. Migrants have the potential to be health-related development agents, but the health information migrants receive while abroad and remit back to their home countries varies by destination country context.


Assuntos
Anticoncepção/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Relações Interpessoais , Migrantes/psicologia , Adulto , Afeganistão/etnologia , Anticoncepção/métodos , Estudos Transversais , Feminino , Humanos , Disseminação de Informação , Irã (Geográfico) , Masculino , Paquistão , Migrantes/estatística & dados numéricos
4.
Nature ; 480(7375): 72-4, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22129726

RESUMO

Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae. They release ultra-relativistic jets, which produce non-thermal emission through synchrotron radiation as they interact with the surrounding medium. Here we report observations of the unusual GRB 101225A. Its γ-ray emission was exceptionally long-lived and was followed by a bright X-ray transient with a hot thermal component and an unusual optical counterpart. During the first 10 days, the optical emission evolved as an expanding, cooling black body, after which an additional component, consistent with a faint supernova, emerged. We estimate its redshift to be z = 0.33 by fitting the spectral-energy distribution and light curve of the optical emission with a GRB-supernova template. Deep optical observations may have revealed a faint, unresolved host galaxy. Our proposed progenitor is a merger of a helium star with a neutron star that underwent a common envelope phase, expelling its hydrogen envelope. The resulting explosion created a GRB-like jet which became thermalized by interacting with the dense, previously ejected material, thus creating the observed black body, until finally the emission from the supernova dominated. An alternative explanation is a minor body falling onto a neutron star in the Galaxy.

5.
Cleft Palate Craniofac J ; 53(2): 210-21, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26090789

RESUMO

Postoperative reossification is a common clinical correlate following surgery. It has been suggested that an underexpression of transforming growth factor-ß3 (TGF-ß3) may be related to craniosynostosis and postoperative reossification. Adding TGF-ß3 may delay reossification and improve postoperative growth. The present study was designed to test this hypothesis. Thirty 10-day-old New Zealand white rabbits with hereditary coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 14), (2) suturectomy treated with bovine serum albumin (n = 8), and (3) suturectomy treated with TGF-ß3 protein (n = 8). At 10 days of age, a 3-mm × 15-mm coronal suturectomy was performed, and serial three-dimensional (3D) computed tomography (CT) scans and cephalographs were taken at 10, 25, 42, and 84 days of age. Calvaria were harvested at 84 days of age for histomorphometric analysis. Mean differences were analyzed using a group by age analysis of variance. Analysis of the 3D CT scan data revealed that sites treated with TGF-ß3 had significantly (P < .05) greater defect areas and significantly (P < .05) greater intracranial volumes through 84 days of age compared with controls. Histomorphometry showed that sites treated with TGF-ß3 had patent suturectomy sites and significantly (P < .001) less new bone in the suturectomy site compared with controls. Serial radiograph data revealed significant (P < .05) differences in craniofacial growth from 25 to 84 days in TGF-ß3-treated rabbits compared with controls. Data show that TGF-ß3 administration delayed reossification and improved craniofacial growth in this rabbit model. These findings also suggest that this molecular-based therapy may have potential clinical use.


Assuntos
Craniossinostoses/cirurgia , Osteogênese/efeitos dos fármacos , Fator de Crescimento Transformador beta3/farmacologia , Animais , Cefalometria , Suturas Cranianas/diagnóstico por imagem , Suturas Cranianas/cirurgia , Craniossinostoses/diagnóstico por imagem , Imageamento Tridimensional , Coelhos , Tomografia Computadorizada por Raios X
6.
Phys Rev Lett ; 113(9): 094801, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25215987

RESUMO

Relativistic electron bunches circulating in accelerators are subjected to a dynamical instability leading to microstructures at millimeter to centimeter scale. Although this is a well-known fact, direct experimental observations of the structures, or the field that they emit, remained up to now an open problem. Here, we report the direct, shot-by-shot, time-resolved recording of the shapes (including envelope and carrier) of the pulses of coherent synchrotron radiation that are emitted, and that are a "signature" of the electron bunch microstructure. The experiments are performed on the UVSOR-III storage ring, using electrical field sensitive YBa2Cu3O(7-x) thin-film ultrafast detectors. The observed patterns are subjected to permanent drifts, that can be explained from a reasoning in phase space, using macroparticle simulations.

7.
Phys Rev Lett ; 110(15): 157001, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25167299

RESUMO

Interfacing photonic and solid-state qubits within a hybrid quantum architecture offers a promising route towards large scale distributed quantum computing. Ideal candidates for coherent qubit interconversion are optically active spins, magnetically coupled to a superconducting resonator. We report on an on-chip cavity QED experiment with magnetically anisotropic Er(3+)∶Y2SiO5 crystals and demonstrate collective strong coupling of rare-earth spins to a lumped element resonator. Moreover, the electron spin resonance and relaxation dynamics of the erbium spins are detected via direct microwave absorption, without the aid of a cavity.

8.
Appl Phys B ; 106(2): 379-384, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23144537

RESUMO

The predicted spectral phase of a fiber continuum pulsed source rigorously quantified by the scalar generalized nonlinear Schrödinger equation is found to be in excellent agreement with that measured by multiphoton intra-pulse interference phase scan (MIIPS) with background subtraction. This cross-validation confirms the absolute pulse measurement by MIIPS and the transform-limited compression of the fiber continuum pulses by the pulse shaper performing the MIIPS measurement, and permits the subsequent coherent control on the fiber continuum pulses by this pulse shaper. The combination of the fiber continuum source with the MIIPS-integrated pulse shaper produces compressed transform-limited 9.6 fs (FWHM) pulses or arbitrarily shaped pulses at a central wavelength of 1020 nm, an average power over 100 mW, and a repetition rate of 76 MHz. In comparison to the 229-fs pump laser pulses that generate the fiber continuum, the compressed pulses reflect a compression ratio of 24.

9.
Opt Express ; 19(19): 18593-601, 2011 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-21935228

RESUMO

We demonstrate the transfer of single photon triggered electrical pulses from a superconducting nanowire single photon detector (SNSPD) to a single flux quantum (SFQ) pulse. We describe design and test of a digital SFQ based SNSPD readout circuit and demonstrate its correct operation. Both circuits (SNSPD and SFQ) operate under the same cryogenic conditions and are directly connected by wire bonds. A future integration of the present multi-chip configuration seems feasible because both fabrication process and materials are very similar. In contrast to commonly used semiconductor amplifiers, SFQ circuits combine very low power dissipation (a few microwatts) with very high operation speed, thus enabling count-rates of several gigahertz. The SFQ interface circuit simplifies the SNSPD readout and enables large numbers of detectors for future compact multi-pixel systems with single photon counting resolution. The demonstrated circuit has great potential for scaling the present interface solution to 1,000 detectors by using a single SFQ chip.

10.
Orthod Craniofac Res ; 14(3): 149-55, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21771269

RESUMO

INTRODUCTION: The gene-environmental interaction model for craniofacial development proposes that if a genetic predisposition for an anomaly is coupled with an environmental factor that can exacerbate this predisposition, more severe phenotypes will result. Here, we utilize cells derived from our non-syndromic rabbit model of craniosynostosis to test the hypothesis that an insult, testosterone (TP) administration (exogenous source) will alter the osteogenic activity of these cells. DESIGN: Calvarial cells from wild-type (WT) (N=13) or craniosynostotic (CS) rabbits (N=11) were stimulated with TP, an androgen receptor blocker, flutamide, and combined treatments. Proliferation and differentiation assays were conducted after 7 days. anova and t-tests were used to determine differences in stimulation and cell type. RESULTS: The CS cells had significantly greater proliferation after TP administration compared to WT. There were no appreciable changes in differentiation after TP stimulation. Flutamide administration or combined TP and flutamide administration decreased both proliferation and differentiation for both cell types similarly. CONCLUSIONS: Testosterone exposure caused an increase in cell proliferation for CS osteoblast cells. However, a therapy targeted to mitigate this response (flutamide therapy) similarly affected CS and WT cells, suggesting that the administration of flutamide or TP in the presence of flutamide decreases osteogenesis of these cells. Thus, although our data support a mechanism of gene-environmental interaction, these results would not support a therapeutic intervention based on this interaction.


Assuntos
Androgênios/farmacologia , Craniossinostoses/patologia , Interação Gene-Ambiente , Osteoblastos/efeitos dos fármacos , Crânio/efeitos dos fármacos , Testosterona/farmacologia , Fosfatase Alcalina/análise , Antagonistas de Androgênios/administração & dosagem , Antagonistas de Androgênios/farmacologia , Androgênios/administração & dosagem , Animais , Biomarcadores/análise , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Craniossinostoses/genética , Craniossinostoses/fisiopatologia , Modelos Animais de Doenças , Combinação de Medicamentos , Flutamida/administração & dosagem , Flutamida/farmacologia , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , Coelhos , Crânio/patologia , Testosterona/administração & dosagem , Testosterona/antagonistas & inibidores , Fatores de Tempo
11.
PLoS One ; 16(12): e0260795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34855875

RESUMO

BACKGROUND: The tenosynovial giant cell tumor (TGCT) is a usually benign lesion which arises from the synovium. It affects joints, tendon sheaths and bursae. The clinical course is often unpredictable, and local recurrences frequently occur. The aim of this study was to describe different treatment options, surgical complications, and to develop a follow-up regime based on a systematic literature review and meta-analysis of foot and ankle lesions. METHODS AND RESULTS: 1284 studies published between 01/1966 and 06/2021 were identified. 25 met the inclusion criteria, with a total of 382 patients. Of these, 212 patients had a diffuse (dTGCT) and 170 a localized (lTGCT) TGCT. Patients with a dTGCT had a mean age of 36.6±8.2 years, and 55% were female. The overall complication rate was 24% in dTGCT, irrespective of the therapeutic procedure; the mean follow-up was 37.9±27.4 months with a recurrence rate of 21%, and recurrences occurred between 3 and 144 months, the vast majority (86%) within the first 5 years following intervention. Patients with a lTGCT had a mean age of 31.2±5.7 years, and 53% were female. Complications occurred in 12%. The mean follow-up was 51.1±24.6 months, the recurrence rate was 7%, and recurrence occurred between 1 and 244 months after intervention. CONCLUSION: Diffuse TGCTs of the foot and ankle region have a remarkable recurrence rate irrespective of therapeutic procedures, and most lesions reoccurred within 5, with more than half of these in the first 2 years. The lTGCTs are well treatable lesions, with a low recurrence and a moderate complication rate. Based on these findings, we propose a follow-up regime for the dTGCT including a clinical survey and MR imaging 3 months after surgical intervention (baseline), followed by twice-yearly intervals for the first 2 years, yearly intervals up to the fifth year, and further individual follow-up due to the fact that recurrences can even occur for years later. For the lTGCT a clinical survey and MRT is proposed after 3-6 months after intervention (baseline), followed by annual clinical examination for 3 years, and in case of symptoms MR-imaging. Larger prospective multi-center studies are necessary to confirm these results and recommendations.


Assuntos
Tornozelo/cirurgia , Doenças do Pé/cirurgia , Tumor de Células Gigantes de Bainha Tendinosa/cirurgia , Recidiva Local de Neoplasia/patologia , Complicações Pós-Operatórias/patologia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Tornozelo/patologia , Seguimentos , Doenças do Pé/patologia , Tumor de Células Gigantes de Bainha Tendinosa/patologia , Humanos , Recidiva Local de Neoplasia/etiologia , Complicações Pós-Operatórias/etiologia
12.
Phys Rev Lett ; 104(17): 173002, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482105

RESUMO

In kinematically complete studies we explore double ionization (DI) of Ne and Ar in the threshold regime (I>3x10{13} W/cm{2}) for 800 nm, 45 fs pulses. The basic differences are found in the two-electron momentum distributions-"correlation" (CO) for Ne and "anticorrelation" (ACO) for Ar-that can be partially explained theoretically within a 3D classical model including tunneling. Transverse electron momentum spectra provide insight into "Coulomb focusing" and point to correlated nonclassical dynamics. Finally, DI threshold intensities, CO as well as ACO regimes are predicted for both targets.

13.
Int Psychogeriatr ; 22(7): 1161-71, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20478100

RESUMO

BACKGROUND: Understanding the prevalence, incidence and cofactors of depression among long-term elderly nursing home (LTNH) residents domiciled for eight months or more may help optimize depression treatment in this vulnerable group. We quantified first year depression in American LTNH residents and the associations between depression and resident/facility characteristics. METHODS: Data were obtained from the Minimum Data Set and Online Survey Certification and Reporting for 634,060 LTNH residents admitted from 1999 to 2005 in 4,216 facilities. Depression first diagnosed at admission and at subsequent quarterly intervals through the first year of stay was examined. Logistic regressions modeled correlates of newly identified depression in each time-period. RESULTS: Recorded depression at admission and during the first year increased from 1999 to 2005. By 2005, 54.4% of LTNH residents had depression diagnosed over the first year; 32.8% at admission and a further 21.6% later during the first year. Antidepressant use was reported prior to depression diagnosis for 48% of those first identified depressed after admission. Men, non-Hispanic blacks, never married, and severely-cognitively impaired LTNH residents were less often identified with depression, particularly at admission. Pain and physical comorbidity were positively associated with depression identified throughout the first year. Prior institutionalization was associated with depression at admission, but not new depression after admission. Facility characteristics had weaker associations with depression. CONCLUSIONS: High depression rates at admission and during the first year indicate a need to monitor and treat large numbers of American LTNH residents for depression. Reduced associations between demographics and depression as stays progress suggest other factors have increased roles in depression etiology.


Assuntos
Depressão/diagnóstico , Depressão/epidemiologia , Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Casas de Saúde/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Feminino , Humanos , Incidência , Tempo de Internação , Assistência de Longa Duração , Masculino , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
14.
Gesundheitswesen ; 72(11): 790-6, 2010 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-20104447

RESUMO

BACKGROUND: The risk compensation scheme (RCS) in the Statutory Health Insurance (SHI) was implemented in 1994 to discourage risk selection between sickness funds. However, several expertise papers have concluded since then that the sociodemographic risk adjusters in place could not adequately curb risk selection. To minimise incentives for risk selection in the Statutory Health Insurance (SHI) further, the RCS was refined in 2009 by adding 80 diseases as additional risk adjusters. In spite of the better compensation of differences in morbidity, however, incentives for risk selection may still persist. In this study, we investigated the association of indicators such as region (number of inhabitants in the city), income, level of education and family status (children in the household) with health care costs to determine if risk selection is still attractive for sickness funds under the refined RCS. METHOD: The analysis is based on a 2002 cross-section survey comprising 75,122 individuals. Health expenditures were estimated using self-documented utilisation data and were standardised for age, sex and diagnoses covered by the risk adjustment scheme. We included costs for inpatient care, outpatient care, pharmaceuticals, rehabilitation, and medical devices. To assess the effects of the above-mentioned individual characteristics on health-care expenditure, regression analyses and analyses of variances were performed. RESULTS: Full documentation was available for 52,484 individuals (69.86%). From these the variables "family status (children in the household)", "higher educational level", and "higher income" were associated with lower costs for individuals without chronic conditions. For individuals with chronic conditions, results were mixed. "Family status", "education" and "income" showed no clear association with lower or higher costs and were not statistically significant. The variable "region" was neither significantly associated with chronically ill nor for healthy individuals. DISCUSSION: With respect to age, sex, and morbidity, individuals with high income and education and without chronic diseases apparently cause lower costs. Thus, health status, income and education remain as possible selection criteria for sickness funds in Germany. However, the refined RCS compensates for the largest proportion of cost differences between insured with and without chronic disease. Possible causes of the small but remaining differences and whether improving preventive programmes or providing awareness campaigns may be appropriate strategies to tackle this issue should be investigated in future research.


Assuntos
Gastos em Saúde/estatística & dados numéricos , Indicadores Básicos de Saúde , Morbidade , Programas Nacionais de Saúde/economia , Risco Ajustado/economia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença Crônica/economia , Atenção à Saúde/economia , Escolaridade , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Razão de Chances , Fatores Sexuais , Fatores Socioeconômicos , Estatística como Assunto , Adulto Jovem
15.
Science ; 219(4581): 172-4, 1983 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-17841686

RESUMO

Platy intergrowths of crystalline todorokite are associated with biogenic debris in the cores of manganese nodules from a site in the Pacific Ocean. Analyses by electron diffraction and transmission electron microscopy demonstrate that this material is composed of tunnels of chains of linked MnO(6) octahedra. The chemical composition, morphology, and stability of the todorokite differ from those of nickel-and copper-rich manganese oxides in nodules that have been identified as todorokite or buserite in earlier investigations.

16.
Science ; 217(4566): 1255-6, 1982 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-6810465

RESUMO

Both 5-hydroperoxyeicosatetraenoic acid (5-HPETE) and 5-hydroxyeicosatetraenoic acid (5-HETE) increased the short-circuit current (Isc) in rabbit colonic mucosa mounted in vitro in Ussing chambers. Measurements of chlorine-36 fluxes indicated that the Isc response to 5-HPETE is due to stimulation of active chlorine secretion. 9-, 11-, and 12-HPETE's and leukotrienes C4 and B4 produced either very small increases in Isc or no increase. In contrast to results in rabbit colon, no HPETE, HETE, or leukotriene was effective in rabbit ileal mucosa. The effects of 5-HPETE in the rabbit colon were unaffected by mepacrine, but could be partially blocked by indomethacin. These results suggest that drugs which block both cyclooxygenase and lipoxygenase may be effective antidiarrheals in patients with colitis.


Assuntos
Ácidos Araquidônicos/farmacologia , Colo/fisiopatologia , Diarreia/fisiopatologia , Ácidos Hidroxieicosatetraenoicos , Leucotrienos , Inibidores de Lipoxigenase , Animais , Bicarbonatos/metabolismo , Cloretos/metabolismo , Colite/fisiopatologia , Íleo/fisiopatologia , Indometacina/farmacologia , Coelhos
17.
Science ; 269(5220): 98-101, 1995 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-7541558

RESUMO

Mouse retinal ganglion cell axons growing from the eye encounter embryonic neurons at the future site of the optic chiasm. After in vivo ablation of these chiasm neurons with a monoclonal antibody and complement, retinal axons did not cross the midline and stalled at approximately the entry site into the chiasm region. Thus, in the mouse, the presence of early-generated neurons that reside at the site of the future chiasm is required for formation of the optic chiasm by retinal ganglion cell axons.


Assuntos
Axônios/fisiologia , Neurônios/fisiologia , Quiasma Óptico/embriologia , Células Ganglionares da Retina/fisiologia , Vias Visuais/embriologia , Animais , Anticorpos Monoclonais , Axônios/ultraestrutura , Proteínas de Transporte/imunologia , Receptores de Hialuronatos , Hipotálamo/citologia , Hipotálamo/embriologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/ultraestrutura , Quiasma Óptico/citologia , Nervo Óptico/embriologia , Receptores de Superfície Celular/imunologia , Receptores de Retorno de Linfócitos/imunologia , Retina/embriologia
18.
Science ; 222(4622): 385-9, 1983 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-6194563

RESUMO

A protoplast fusion method was developed to stably transfect human cells with pSV2-derived plasmids at frequencies greater than 10(-3). This procedure made it possible to test the biological effect of a hepatitis B virus (HBV) gene independent of the viral structures required for infection. A pSV2gpt+ plasmid constructed to carry a subgenomic fragment of HBV that contained the core antigen gene (HBc gene) was transfected into human cells. A human epithelial cell line was stably transfected with the HBc+ gene by selecting recipient cells for expression of guanine phosphoribosyl transferase expression. With this gpt+/HBc+ cell line it was shown that growth in serum-free medium or treatment with 5'-azacytidine stimulates the production of the HBV core antigen. A hepatocellular carcinoma carrying the entire HBV genome was stimulated to produce the HBc gene product in response to the same factors that stimulated HBcAg production in the gpt+/HBc+ cell line constructed by transfection. The temporal relation between the cytopathologic response and HBc gene expression was similar for both cell types, indicating a primary role for HBc gene expression in the cytopathology of HBV-infected human liver.


Assuntos
Transformação Celular Viral , Antígenos do Núcleo do Vírus da Hepatite B/genética , Azacitidina/farmacologia , Fusão Celular , Células Cultivadas , Efeito Citopatogênico Viral , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Virais , Humanos , Transfecção
19.
Tob Control ; 18(1): 64-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19168490

RESUMO

A marked shift in tobacco-related workplace health promotion intervention involves the adoption of policies barring employment to smokers. We discuss the potential public health consequences of these policies on those affected-smokers, their families, the surrounding community and society at large. We find a lack of published evidence evaluating the effectiveness and consequences of these policies. By developing a model of policy effects, we outline possible unintended consequences. With such large gaps in the evidence base and the potential for deleterious consequences, we argue for increased discussion about the use of smoker-free employment policies as a public health intervention and for increased engagement of employers by the public health community in worksite health promotion.


Assuntos
Emprego/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Saúde Ocupacional/legislação & jurisprudência , Seleção de Pessoal/legislação & jurisprudência , Fumar/legislação & jurisprudência , Poluição por Fumaça de Tabaco/legislação & jurisprudência , Emprego/ética , Humanos , Transtornos Mentais/etiologia , Modelos Organizacionais , Seleção de Pessoal/ética , Saúde Pública/ética , Saúde Pública/legislação & jurisprudência , Fumar/psicologia , Prevenção do Hábito de Fumar , Estereotipagem , Poluição por Fumaça de Tabaco/ética , Local de Trabalho/legislação & jurisprudência
20.
Tob Control ; 18(3): 245-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19168475

RESUMO

OBJECTIVE: To determine whether adolescents living in parental homes where smoking is banned are more likely to move into smoke-free living quarters when they leave home. METHODS: We analysed data on 693 youths from a 4-year, three-wave prospective study of a representative sample of Massachusetts adolescents (aged 12-17). All youths resided in independent living quarters at follow-up. The primary outcome was presence of a smoking ban in the living quarters at follow-up. The primary predictor was presence of a household smoking ban in the parental home, assessed 2 years before the outcome. Generalised linear mixed effects models examined the effect of a parental household smoking ban on the odds of moving into smoke-free living quarters at follow-up overall and stratified by smoking status at follow-up. RESULTS: Youths leaving home had much higher odds of moving to smoke-free living quarters if their parental household had had a smoking ban (odds ratio (OR) = 12.70, 95% CI, 6.19 to 26.04). Other independent predictors included moving into a school or college residence (OR = 3.88, 95% CI 1.87 to 8.05), and not living with smokers at follow-up (OR = 3.91, 95% CI 1.93 to 7.92). CONCLUSIONS: A household smoking ban in the parental home appears to lead youths to prefer smoke-free living quarters once they leave home.


Assuntos
Vida Independente/psicologia , Poder Familiar/psicologia , Abandono do Hábito de Fumar/psicologia , Adolescente , Poluição do Ar em Ambientes Fechados , Criança , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Razão de Chances
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