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1.
J Hum Hypertens ; 31(12): 808-814, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28906485

RESUMO

Cardiorespiratory fitness (CRF) and adiposity contribute to high blood pressure (HBP) in adults and children. However, their relative importance as risk factors is unknown. We examined the relationships between weight status, CRF and HBP among Chinese primary school children. A cross-sectional study was conducted with 4926 school children aged 5-12 years. CRF was estimated from a modified Cooper test, body mass index z-scores and weight categories were calculated from objective height and weight measurements and BP was measured using an electronic sphygmomanometer. HBP was defined as >95th percentile based on reference cutoffs for Chinese boys and girls. Generalised Linear Mixed models, adjusting for age, pubertal status and height, were developed for boys and girls to explore the independent and combined associations between fitness, weight status and HBP. Seven hundred and fifty-two (15.3%) children had HBP, with a higher prevalence in obese (40.5% and 45.9% in boys and girls, respectively) and overweight (27.6% and 30.2% in boys and girls, respectively) compared with non-overweight (9.0% and 13.8% in boys and girls, respectively) children. HBP prevalence was lower in boys with higher CRF (odds ratio (OR) for the highest vs lowest CRF quartile in boys 0.64; 95% confidence interval (CI) 0.46-0.89). This association was not seen in girls. With weight status and CRF in the same model, weight status, but not CRF, remained significantly associated with HBP (obesity in boys: OR 4.19; 95% CI 2.63-6.67; in girls: OR 2.49; 95% CI 1.19-5.19). The interaction effect for CRF and weight status was non-significant. Overweight/obesity was significantly associated with HBP among children. There was no evidence of modification of this relationship by CRF.


Assuntos
Aptidão Cardiorrespiratória , Hipertensão/epidemiologia , Obesidade/epidemiologia , Peso Corporal , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino
2.
J Thromb Haemost ; 12(4): 497-504, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24517219

RESUMO

BACKGROUND: Immune thrombocytopenia (ITP) is a common autoimmune bleeding disorder, in which platelet glycoprotein (GP)IIb-IIIa and GPIb-IX are the two most frequently targeted autoantigens. Our previous studies in animal models of ITP demonstrated that intravenous immunoglobulin G (IVIG) could protect against anti-GPIIb-IIIa autoantibody-mediated thrombocytopenia but failed to ameliorate ITP induced by most anti-GPIb-IX autoantibodies. OBJECTIVES: The objective of this human study was to evaluate the association between the specificity of antiplatelet autoantibodies and response to IVIG treatment. PATIENTS/METHODS: In this retrospective study, a cohort of 156 previously untreated adults with severe ITP who underwent IVIG therapy (0.4 g kg(-1)  day(-1) for 5 days) was analyzed. The primary outcome was response defined as platelet counts of ≥ 30 × 10(9)  L(-1) and a doubling of baseline counts within 7 days of dosing, and an absence of bleeding. RESULTS AND CONCLUSIONS: Among the 66 patients with anti-GPIb-IX autoantibodies, only 24 (36.4%) achieved a response, as compared with 72 of 90 patients (80.0%) who were negative for anti-GPIb-IX autoantibodies (relative risk 2.2; 95% confidence interval 1.6-3.1). This study found no difference in response between patients with anti-GPIIb-IIIa autoantibodies (61.7%) and those without anti-GPIIb-IIIa autoantibodies (61.3%). Logistic regressions, including main effects and the interaction between these two autoantibodies, showed no influence of anti-GPIIb-IIIa autoantibodies on the effects of anti-GPIb-IX autoantibodies with regard to their association with IVIG response. Thus, in adults with ITP, the presence of anti-GPIb-IX autoantibodies is a predictive factor for poor response to IVIG treatment. TRIAL REGISTRATION: ClinicalTrials.gov NCT01666795.


Assuntos
Autoanticorpos/química , Imunoglobulina G/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/terapia , Adulto , Especificidade de Anticorpos , Plaquetas/imunologia , Peso Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/imunologia , Complexo Glicoproteico GPIb-IX de Plaquetas/imunologia , Púrpura Trombocitopênica Idiopática/sangue , Estudos Retrospectivos , Resultado do Tratamento
3.
J Chem Phys ; 137(19): 194703, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23181328

RESUMO

Metal octaethylporphyrins (M-OEP), M-N(4)C(20)H(4)(C(2)H(5))(8), adsorbed at a metallic substrate are promising candidates to provide spin dependent electric transport. Despite these systems having been studied extensively by experiment, details of the adsorbate geometry and surface binding are still unclear. We have carried out density functional theory calculations for cobalt octaethyl porphyrin (Co-OEP) adsorbate at clean and oxygen-covered Ni(100) surfaces as well as for the free Co-OEP molecule where equilibrium structures were obtained by corresponding energy optimizations. These geometries were then used in calculations of Co-OEP carbon and nitrogen 1s core excitations yielding theoretical excitation spectra to be compared with corresponding K-edge x-ray absorption fine structure (NEXAFS) measurements. The experimental NEXAFS spectra near the carbon K-edge of Co-OEP bulk material show large intensity close to the ionization threshold and a triple-peak structure at lower energies, which can be reproduced by the calculations on free Co-OEP. The experimental nitrogen K-edge spectra of adsorbed Co-OEP layers exhibit always a double-peak structure below ionization threshold, independent of the layer thickness. The peaks are shifted slightly and their separation varies with adsorbate-substrate distance. This can be explained by hybridization of N 2p with corresponding 3d contributions of the Ni substrate in the excited final state orbitals as a result of adsorbate-substrate binding via N-Ni bond formation.

4.
J Nanosci Nanotechnol ; 11(3): 2722-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449462

RESUMO

Magnetic properties, phase evolution, and microstructure of melt spun Hf-substituted Sm(Co0.97Hf0.03)(x)Cy (x = 5-9; y = 0-0.1) ribbons quenched at the wheel speed of 40 m/s are investigated. X-ray diffraction analysis shows that the main phases existed in Sm(Co0.97Hf0.03)(x) ribbons are 1:5 phase for x = 5-5.5; 1:5 and 1:7 phases for x = 6; 1:7 phase for x = 6.5-7.5; 1:7 and 2:17 phases for x = 8; and only 2:17 phase for x = 8.5-9, respectively. For Sm(Co0.97Hf0.03)(x) (x = 5-9) ribbons, the optimum magnetic properties of B(r) = 5.6 kG, (i)H(c)= 15.6 kOe and (BH)(max) = 7.1 MGOe are obtained for Sm(Co0.97Hf0.03)6.5 ribbons. Furthermore, a slight amount of C addition in Sm(Co0.97Hf0.03)(x) ribbons slightly modify phase constitution and effectively refine the grain size from 200-700 nm for C free ribbons to 10-70 nm, strengthening the exchange coupling effect between magnetic grains of the ribbons. As a result, magnetic properties are further improved. The magnetic properties of B(r) = 6.9 kG, (i)H(c) = 9.2 kOe and (BH)(max) = 10.0 MGOe can be achieved for Sm(Co0.97Hf0.03)7.5C0.1 nanocomposites.


Assuntos
Cristalização/métodos , Magnetismo , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Samário/química , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Rotação , Propriedades de Superfície
5.
ACS Nano ; 4(6): 3045-52, 2010 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-20565140

RESUMO

p-Type surface conductivity is a uniquely important property of hydrogen-terminated diamond surfaces. In this work, we report similar surface-dominated electrical properties in silicon nanowires (SiNWs). Significantly, we demonstrate tunable and reversible transition of p(+)-p-i-n-n(+) conductance in nominally intrinsic SiNWs via changing surface conditions, in sharp contrast to the only p-type conduction observed on diamond surfaces. On the basis of Si band energies and the electrochemical potentials of the ambient (pH value)-determined adsorbed aqueous layer, we propose an electron-transfer-dominated surface doping model, which can satisfactorily explain both diamond and silicon surface conductivity. The totality of our observations suggests that nanomaterials can be described as a core-shell structure due to their large surface-to-volume ratio. Consequently, controlling the surface or shell in the core-shell model represents a universal way to tune the properties of nanostructures, such as via surface-transfer doping, and is crucial for the development of nanostructure-based devices.


Assuntos
Cristalização/métodos , Modelos Químicos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Nanotubos/química , Nanotubos/ultraestrutura , Silício/química , Simulação por Computador , Condutividade Elétrica , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
6.
J Thromb Haemost ; 6(1): 158-65, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17944988

RESUMO

BACKGROUND: Platelet glycoprotein (GP)-reactive CD4+ T cells are essential for the stimulation and maintenance of antiplatelet autoantibody production in chronic idiopathic thrombocytopenic purpura (ITP). Blocking costimulatory signals could result in platelet-specific T-cell anergy. METHODS: GP-specific CD4+ T cells from patients with ITP were made anergic using cytotoxic T-lymphocyte-associated antigen 4 immunoglobulin (CTLA4-Ig). The CTLA4-Ig-induced GP-specific anergic T cells were investigated for their inhibitory function on GP-reactive T-cell proliferation and antibody production with in vitro culture systems. To further analyze their tolerizing mechanisms, we cocultured GP-anergic T cells with dendritic cells (DCs) from patients with ITP. RESULTS: Our studies demonstrated that the anergized GP-specific T cells have profound effects on both GP-specific T-cell proliferation and antibody production. These anergic T cells exerted their suppressive effects mainly in a cell contact-dependent manner, and they were not constitutively suppressive but required specific antigen stimulation to make DCs tolerogenic. The anergic T-cell-modulated DCs could induce the autoreactive T cells to be tolerant, and this effect was not restricted to T cells of the same specificity. CONCLUSION: Our studies demonstrate the efficacy of CTLA4-Ig in suppressing the pathologic autoimmune responses in ITP. These findings provide new insights into the underlying mechanisms of anergy induction in chronic ITP.


Assuntos
Autoimunidade/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Anergia Clonal/efeitos dos fármacos , Tolerância Imunológica/efeitos dos fármacos , Imunoconjugados/farmacologia , Púrpura Trombocitopênica Idiopática/imunologia , Abatacepte , Adolescente , Adulto , Formação de Anticorpos/efeitos dos fármacos , Apresentação de Antígeno , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/imunologia , Células Dendríticas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 18(4): 208-10, 1997 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-9812519

RESUMO

A strain of poliovirus type 1 isolated from an endemic in Shandong Province in 1988 and three strains of poliovirus type 1 isolated from an endemic in Xinjiang in 1990 were analysed by dot blot hybridization with Sabin I specific probe and PCR amplification with Sabin I specific primers. They were proved to be non-Sabin-like poliovirus. The nucleotide sequences of VP1-2A junction region of four poliovirus type 1 isolates were analysed. It was found that the nucleotide diversity of four isolates with Sabin I was equal to or greater than 16.7%. This finding proved that they were wild polioviruses and greatly different fromSabin I. It was also found that the nucleotide sequence diversity among three strains from Xinjiang was very small (less than 2.6%) with identical amino acid sequences. This indicated that the three Xinjiang strains belonged to the same genotype. While the difference of Shandong strain from the three Xinjiang strains was between 14. 0% to 15.33% in nucleotide sequence and 2.0% to 4.0% in amino acids. This indicated that Shandong strain was apparently different from three Xinjiang strains and it belonged to another wild genotype which had a different history of evolution.


Assuntos
DNA Viral/genética , Poliomielite/epidemiologia , Poliovirus/genética , Sequência de Aminoácidos , Sequência de Bases , Criança , China/epidemiologia , Humanos , Dados de Sequência Molecular , Poliomielite/virologia , Vacina Antipólio Oral/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência
8.
Dev Biol ; 184(1): 61-9, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9142984

RESUMO

Steel factor (SLF) and its cognate receptor, c-kit, have been implicated in the generation of melanocytes from migrating neural crest (NC) cells during early vertebrate embryogenesis. However, the source of SLF in the early avian embryo and its precise role in melanogenesis are unclear. We report here that NC cells themselves express and release SLF protein, which in turn acts as an autocrine factor to induce melanogenesis in nearby NC cells. These results indicate that NC cell subpopulations play an active role in the determination of their cell fate and suggest a different developmental role for the embryonic microenvironment than what has been previously proposed.


Assuntos
Melanócitos/citologia , Crista Neural/citologia , Fator de Células-Tronco/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Coturnix , Fator 2 de Crescimento de Fibroblastos/farmacologia , Dados de Sequência Molecular , Crista Neural/embriologia , Crista Neural/metabolismo , Especificidade de Órgãos , RNA Mensageiro/análise , Fator de Células-Tronco/análise , Fator de Células-Tronco/genética , Fator de Células-Tronco/metabolismo , Fator de Células-Tronco/farmacologia
10.
Opt Lett ; 21(18): 1511-2, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19881708

RESUMO

We propose and experimentally demonstrate a novel dot-array recording method in which rainbow holograms are used for the purpose of making hard copies of three-dimensional image data stored in computers.

11.
Opt Lett ; 21(20): 1664-6, 1996 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19881760

RESUMO

A silicon-on insulator (SOI) zero-gap directional coupler switch is studied based on the large-cross-section singlemode rib waveguide condition, the dual-mode interference principle, and the free-carrier plasma dispersion effect, in which the SOI technique uses silicon and silicon dioxide thermal bonding and backpolishing. The SOI is fabricated by potassium hydroxide anisotropic etching. Its insertion loss and cross talk are measured to be less than 4.81 dB and 218.6 dB, respectively, at a wavelength of 1.3 microm and a switching voltage of 0.91 V. Response time is ~210 ns.

12.
Opt Lett ; 18(1): 69-71, 1993 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19798353

RESUMO

A novel and simple method of 360 degrees holography, the large-angle one-step annular-aperture rainbow hologram, is proposed and experimentally demonstrated. A special problem connected with this technique, the effect of a conjugate image in reconstruction, is analyzed, and the condition for avoiding its interference is derived.

13.
Zhonghua Fu Chan Ke Za Zhi ; 26(5): 266-7, 321, 1991 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-1935403

RESUMO

Air sac midwifery technique is developed in this hospital to cut down the duration of labor (birth process). A special small sac is placed inside the ripe cervix and vagina of women of term pregnancy, and aerated slowly till a positive pressure of 16-25 kPa is reached. The cervix can be dilated to 6 to 8 cm, and the vagina 10 to 12 cm in 1 to 2 minutes. The labor course may be cut down by 8 to 10 hours, thus relieving the parturient from pain, lessening perineal laceration and perinatal mortality which is important for eugenics sake.


Assuntos
Trabalho de Parto , Tocologia/métodos , Adulto , Feminino , Humanos , Tocologia/instrumentação , Gravidez , Fatores de Tempo
14.
Opt Lett ; 16(22): 1777-9, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19784137

RESUMO

A novel method to increase the diffraction efficiency of a common silver halide amplitude hologram, postheat treatment, is proposed and experimentally demonstrated. The method is simple and needs no chemicals. The physical mechanism of this process is also discussed.

15.
J Infect Dis ; 152(1): 137-44, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2861242

RESUMO

During an outbreak of hemorrhagic fever with renal syndrome in the Anhui Province of China, a door-to-door survey was conducted of all of the 10,024 residents of eight village communities. The incidence rates were higher in males than in females and higher in adults than in children. Of all the residents surveyed, however, those who had slept on the ground or had been engaged in heavy farm work were at a significantly higher risk of illness than were those who slept on wooden beds or did light work. Among men who did heavy farm work and who gave a history of sleeping in straw huts on the drained swamp, the attack rate was 2.33 times higher than it was for those sleeping exclusively in their permanent homes. Among both sexes, threshers had a significantly higher attack rate than did nonthreshers. Suspicions that trombiculid mites or gamasoid mites act as vehicles of transmission cannot be accepted as an explanation for the association of the risk of illness with the type of work done and with sleeping arrangements. Circumstantial evidence supports our hypotheses of airborne transmission and transmission by inoculation of infectious materials into skin lesions.


Assuntos
Febre Hemorrágica com Síndrome Renal/transmissão , Adolescente , Adulto , Fatores Etários , Animais , Leitos , Criança , Pré-Escolar , China , Feminino , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/etiologia , Habitação , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Ácaros , Ocupações , Risco , Roedores , Estações do Ano , Fatores Sexuais
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