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1.
Appl Radiat Isot ; 192: 110603, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36508958

RESUMO

A highly flexible stretchable thermoplastic polyurethane (TPU) composite loaded with a low-melting-point Ga1In1Sn7Bi1 multiprincipal element alloy (LMPEA) was prepared, and its radiation shielding performance was evaluated. The fluid characteristic of LMPEA and the flexibility of TPU enable good interface compatibility. Ga1In1Sn7Bi1 LMPEA consists of two eutectic structures, and the liquid gallium-rich phases are distributed at the boundary of the InBi intermetallic compound and Sn solid solution. In the low-photon energy range of 30-80 keV, LMPEA has a theoretical specific lead equivalent of 0.803 mmPb/mm and a theoretical weight reduction of 17.27% compared with lead. To evaluate the photon attenuation capability for the LMPEA/TPU composites, the Phy-X procedure and Monte Carlo simulations were used to determine the shielding parameters, such as the mass attenuation coefficient, linear attenuation coefficient, half-value layer, tenth-value layer, mean free path, effective atomic number, and fast neutron removal cross section. The attenuation performance test of X-ray protective materials measured the actual lead equivalent. At the same thickness, the LMPEA/TPU composite (66.667, 50.000 wt% LMPEA loading) has a higher measured lead equivalent than the in-service medical shielding materials, which meets the lead equivalent requirements of X-ray protective clothing. LMPEA/TPU composites are nontoxic, lightweight, and have excellent low-energy X-ray shielding ability, offering great potential for application in medical wearable materials.


Assuntos
Poliuretanos , Proteção Radiológica , Raios X , Proteção Radiológica/métodos , Radiografia , Método de Monte Carlo
2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(12): 1285-1290, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36567584

RESUMO

OBJECTIVE: To observe the results of electroacupuncture (EA) on the resuscitation of a rat model of asphyxia cardiac arrest (CA). And to explore its effect on the neurologic deficits and hemodynamic instability of post-cardiac arrest syndrome (PCAS). METHODS: A total of 107 male SD rats were randomly divided into sham, CA, and EA groups. Each group received arterial catheterization and tracheal intubation. The sham group was not induced asphyxia. Asphyxial cardiac arrest was established by endotracheal tube clamping. Rats in the CA group received basic respiratory support and fluid resuscitation in return of spontaneous circulation (ROSC) and rats in the EA group received EA at Baihui based on the treatment of CA group after ROSC, with a dense-dispersed wave at frequencies of 4-20 Hz, while the current intensity was adjusted minimum to induce a twitch of the scalp, the course of treatment was 30 minutes. The baseline data, hemodynamics after ROSC, neurological deficit score (NDS), pathological changes of brain tissue, and levels of serum biomarker were recorded and compared among the three groups. The 72-hour survival of rats was analyzed by Kaplan-Meier survival curve. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of necrotic neurons in the hippocampal CA1 region of rat brain. Meanwhile, Nissl staining and TdT-mediated dUTP nick-end labeling (TUNEL) were used to detect cell apoptosis and injury. RESULTS: Compared with the CA group, the mean arterial pressure (MAP) in the EA group increased significantly at 15 minutes after ROSC [mmHg (1 mmHg ≈ 0.133 kPa): 125.00 (94.00, 136.25) vs. 92.00 (72.00, 122.50), P < 0.05]. There was no significant difference in the NDS score between the EA group and the sham group. Still, the NDS score of the rats in the CA group at 6 hours after ROSC were significantly lower than that in the sham group (46.00±10.61 vs. 80.00±0.00, P < 0.05). Kaplan-Meier survival curve analysis showed that EA did not improve the 72-hour survival rate of rats (100% in the sham group, 25% in the CA group, and 30% in the EA group, P > 0.05). The analysis by TUNEL showed that the apoptosis rate of neurons in CA1 region of the hippocampus in EA group at 6 hours after ROSC was significantly lower than that in CA group [(62.84±2.67)% vs. (71.29±3.70)%, P < 0.05]. Compared with the CA group, the level of serum S100 calcium binding protein B (S100B) in the EA group at 6 hours after ROSC was significantly lower (ng/L: 19.30±13.87 vs. 132.28±31.67, P < 0.05), but there were no significant differences in the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) between these two groups. CONCLUSIONS: In the present study, EA at Baihui can stabilize the hemodynamic, moreover, it has a particular neuroprotective effect on PCAS rats. Still, EA at Baihui does not reduce the systemic inflammatory response and improve the survival rate of rats, and its mechanism remains to be verified in further research.


Assuntos
Reanimação Cardiopulmonar , Eletroacupuntura , Parada Cardíaca , Síndrome Pós-Parada Cardíaca , Animais , Masculino , Ratos , Asfixia/complicações , Asfixia/terapia , Parada Cardíaca/terapia , Hemodinâmica , Ratos Sprague-Dawley
3.
Medicine (Baltimore) ; 100(15): e23736, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33847606

RESUMO

BACKGROUND: Shenfu Injection (SFI) is a promising alternative treatment for heart failure (HF) in China. Many complete clinical trials have examined the efficacy of SFI combined use with conventional treatment (CT) vs CT alone. This study is to conduct a systematic review and meta-analysis of randomized clinical trials to evaluate the benefits and risks of using SFI in addition to CT for the treatment of HF. METHOD: All the trials will be searched through 4 English databases (MEDLINE via PubMed, the Cochrane Library, EMBASE, Web of Science) and 4 Chinese databases (the China Science and Technology Journal Database, Chinese Biomedical Literature Database, Wan-fang Database, the China National Knowledge Infrastructure.) from October 2005 to June 2019. Conference articles or articles with incomplete data will be removed. The primary outcome was the New York Heart Association, 6-minute walk test, hospitalization or rehospitalization. Left ventricular ejection fraction percentage, left ventricular end-diastolic dimension, Cardiac index, heart rate, N-terminal pronatriuretic peptide and other indicators were also assessed. RevMan V.5.3 Software and Stata 13.0 Statistics Software were used to calculate the data synthesis and conduct meta-analysis according to the guideline of Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols 2015. RESULTS: Mortality, New York Heart Association function classification, heart rate, 6-minute walk test, hospitalization or rehospitalization, Heart rate, systolic blood pressure, DBP, Cardiac minute volume, left ventricular ejection fractions percentage, left ventricular end-diastolic dimension (mm), N-terminal pronatriuretic peptide, etc. and adverse effects will be comprehensively assessed to evaluate the adjunctive effect of SFI through different aspects. We will perform a meta-analysis of each outcome with subgroup analysis based on the type of HF, treatment methods, and course of disease. Sensitivity analysis will be conducted with clinical factors, treatment methods, methodological characteristics, and statistical heterogeneity (if applicable). CONCLUSION: This study will assess the adjunctive effect of SFI and its safety on HF with clinical evidence. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020151856.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Débito Cardíaco , Terapia Combinada , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Hospitalização/estatística & dados numéricos , Humanos , Injeções , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Índice de Gravidade de Doença , Teste de Caminhada
4.
Medicine (Baltimore) ; 98(24): e15408, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31192907

RESUMO

BACKGROUND: The mechanisms of acupuncture on the treatment of cerebral infarction remain unclear, the aim of the present study was to provides a protocol of systematic review and meta-analysis, with which we will collect clinical evidence to verify whether acupuncture will have an effect on reducing the levels of tumor necrosis factor α (TNF-α), C-reactive protein (CRP), interleukin-1 (IL-1), and interleukin (IL-6) after cerebral infarction based on evidence-based studies. METHODS: Included studies will be retrieved according to inclusion and exclusion criteria from 5 English databases (the MEDLINE via PubMed, the Cochrane Library, Embase, the Web of Science, and Ovid database), and 4 Chinese databases (China Science and Technology Journal Database (VIP), Chinese Biomedical Literature Database (CBM), Wan-fang Database, China National Knowledge Infrastructure (CNKI)) from October 1990 to October 2017. The inflammatory factor levels of TNF-α and IL-1,IL-6,CRP will be marked as major outcomes. We will use RevMan V.5.3 software to calculate the data synthesis and will conduct meta-analysis based on the collected data. RESULTS: The inflammatory factor levels of TNF-α and IL-1,IL-6,CRP, mortality and adverse effects will be measured and comprehensively assessed to evaluate the adjunctive effect of XBP on CHF from this systematic review and meta-analysis with current clinical evidence. CONCLUSION: The systematic review and meta-analysis will assess the effect of acupuncture on the expression of inflammatory factors TNF-α, IL-6, IL-1 and CRP in cerebral infarction with up-to-date clinical evidence. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42017078583.


Assuntos
Terapia por Acupuntura/métodos , Proteína C-Reativa/metabolismo , Infarto Cerebral/terapia , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Infarto Cerebral/imunologia , China , Coleta de Dados , Regulação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Software , Resultado do Tratamento , Metanálise como Assunto
5.
RSC Adv ; 9(4): 1939-1948, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35516103

RESUMO

Polycrystalline La0.8(Ca0.12Sr0.08)MnO3:mol%Ag x (LCSMO:Ag x , x = 0, 0.1, 0.2, 0.3 and 0.4) ceramics were synthesized by the sol-gel technique. Structural, electrical and magnetic properties of the LCSMO:Ag x ceramics were investigated in detail. X-ray diffraction (XRD) data analyses revealed that all the samples were crystalized in the orthorhombic structure with space group of Pnma. With the increase in Ag doping (x), the grain sizes of the LCSMO:Ag x samples increased and the amount of grain boundaries (GBs) decreased accordingly. At the same time, the Mn-O bond distance and the Mn-O-Mn bond angles changed correspondingly, leading to the slight increase in the lattice constants (a, b and c) and slight expansion of cell volume (V). For the LCSMO:Ag x sample with x = 0.3, the optimal values of temperature coefficient of resistivity (TCR) and magnetoresistance (MR) reached 16.22% K-1 (265.1 K) and 42.07% K-1 (270.48 K), respectively. In addition, the fitting analysis of ρ-T curves showed that the experimental data were consistent with the theoretical calculation data. In the T < T MI (metal-insulator transition temperature) region, the electrical conduction mechanism of LCSMO:Ag x was clarified by electron-magnon, electron-electron and electron-phonon scattering. In the T > T MI region, the resistivity data were interpreted by using the adiabatic small-polaron hopping model. Furthermore, in the entire temperature range, the phenomenological equation called the percolation model was used to explain the resistivity data and the phase-separation mechanism of ferromagnetic metallic (FM) and paramagnetic insulating (PI) phases. All the obtained results indicated that the improvement in the electrical properties of the LCSMO:Ag x samples was attributed to the doping of Ag, which changed the A-site (La, Ca and Sr ions) average ion radius, the Mn-O-Mn bond angles and the Mn-O bond distance. In addition, the grain size increased, which led to improvement in the Mn4+ ion concentration and the GBs connectivity in the LCSMO:Ag x polycrystalline ceramics.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 2984-8, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20101969

RESUMO

In the present work, the electrochemical deposition of silver was investigated on a glassy carbon electrode from AgNO3 solutions in the presence of RTILs (1-butyl-3-methyl imidazolium nitrate, [bmim]NO3) additive by cyclic voltammetric technique, scanning electron microscope (SEM) and X-ray photon spectroscopy (XPS). For comparison, the electrodeposition of silver from [bmim]NO3-free AgNO3 solution was also investigated. The voltammograms showed that the cathodic peak potential shifted toward more negative potential and the cathodic peak current decreased when 5 x 10(-6) mol x L(-1) [bmim]NO3 was added into AgNO3 solutions. This indicated that [bmim]NO3 produced an inhibition of silver deposition, probably related to the adsorption of [bmim]NO3. SEM images showed that the uniform, shining electrodeposits of silver obtained in AgNO3 solutions were rather compact and that the size of silver grains decreased with the addition of [bmim]NO3 additive. The surface-enhanced Raman scattering (SERS) activities of silver deposits were measured by using methyl orange (MO) as the probe molecules. The strongly enhanced Raman scattering from the monolayer film of MO demonstrated that the as prepared silver particular film was SERS active. The enhancement factor was calculated to be up to 1.7 x 10(5) and 1.1 x 10(5) for silver film obtained in AgNO3 solutions with and without [bmim]NO3 additive, respectively.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(4): 588-90, 2002 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-12938372

RESUMO

Under incident light 514.5 nm, Raman scattering spectrum of trace contraband Heroin on finger with low concentration was investigated. It has been known that contraband Heroin has strong fluorescence background in its Raman scattering under visible excitation. By analyzing the sample surface and applying appropriate experimental method, the high signal-noise ratio quality and low fluorescence Raman spectrum was obtained. The result indicated that it would be much improved the Raman scattering spectrum by using slick Al slice as gasket for drugs and selecting proper area on the sample surface, controlling the incident light power. This work could provide a powerful method for detecting trace materials including drugs, explosives, deleterious material in forensic science.


Assuntos
Heroína/análise , Análise Espectral Raman/métodos , Espalhamento de Radiação
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