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1.
Inorg Chem ; 58(24): 16346-16353, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31789516

RESUMO

Hybrid halide perovskites are emerging semiconducting materials with a diverse set of remarkable optoelectronic properties. Besides the widely studied lead halide perovskites, Pb-free metal halides such as Bi- and Sb-containing hybrid organic-inorganic materials have shown potential as semiconductors and have been deemed candidates for optoelectronic devices. Here, we report a series of 1D Sb/Bi-based organic-inorganic hybrid alloys: [4ApyH]SbxBi1-xIyBr4-y, where 4ApyH stands for the 4-aminopyridine cations. These compounds are assembled by edge-sharing octahedral [MX6] units stabilizing 1D chains with organic cations filled in between. The crystallographic data of eight selected complexes show that [4ApyH]SbxBi1-xIyBr4-y has at least five phases (space group) with the difference metal and halogen content: Pbca ([4ApyH]BiI4), Pca21 ([4ApyH]Sb0.5Bi0.5I4), P21/c ([4ApyH]SbI4 (100 K), [4ApyH]BiI2Br2, [4ApyH]BiBr4, and [4ApyH]SbBr4 (100 K)), I2/a ([4ApyH]Sb0.5Bi0.5I2Br2and [4ApyH]SbI2Br2), and C2/c ([4ApyH]SbI4 (298 K) and [4ApyH]SbBr4 (298 K)). Powder X-ray diffraction shows that the phase of the sample changes with a change of the metal and halogen ratios, and the change law accords with Vegard's law. The optical band gaps are heavily affected by the metal and halide contents, ranging from 1.94 eV for [4ApyH]BiI4 to 2.73 eV for [4ApyH]SbBr4. When Sb substitutes for Bi to form an alloy, the band gap increases from 1.94 for [4ApyH]BiI4 to 1.67 eV for [4ApyH]SbI4, from 2.13 eV for [4ApyH]BiI2Br2 to 2.41 eV for [4ApyH]SbI2Br2, and from 2.55 eV for [4ApyH]BiBr4 to 2.73 eV for [4ApyH]SbBr4. The conductivity of [4ApyH]SbxBi1-xI4 increased from ∼1.00 × 10-15 to 2.14 × 10-8 S cm-1 with an increase of the Sb content. Solution-deposited thin films of the nine complexes show the same (110) orientation, displaying a parallel growth orientation with respect to the substrate. The devices of [4ApyH]Sb0.8Bi0.2I4 and [4ApyH]SbI4 demonstrated stable open-circuit photovoltages of 0.55 and 0.44 V, steady-state short-circuit photocurrent densities of 1.52 and 1.81 mA cm-2, and light-to-electrical energy conversion efficiencies of 0.29% and 0.30%, respectively.

2.
Dalton Trans ; 48(34): 12888-12894, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31389455

RESUMO

The structural information of a material in both the solid state and solution state is essential to the in-depth understanding of the properties of inorganic-organic hybrid materials. A one-dimensional (1D) lead bromide formulated as [H][NH3(CH2)2SS(CH2)2NH3][H2O][PbBr5] (1) could be converted into a new two-dimensional (2D) complex, [NH3(CH2)2SS(CH2)2NH3][PbBr4] (2), by soaking the crystals in water. The isolated 2D compound showed single-layer lead-halide perovskite structures. Electrospray ionization mass spectrometry (ESI-MS) analyses of the reaction solution revealed that the [PbBr3]- fragments are initially formed from the rapid decomposition of the 1D [PbBr5]3- chains and subsequently reassemble into 2D [PbBr4]2- layers, which was verified by powder X-ray diffraction (PXRD) and microcalorimetry. Because of the decomposition and reassembly process, complex 1 could be used as a precursor to synthesize M2+-doped 2D lead bromide perovskites, namely, Mn@2, Ni@2 and Cd@2. In addition, preliminary tests indicated that complex 2 exhibited a lower optical band gap (3.25 eV) and higher electrical conductivity (3.2 × 10-11 S cm-1) than complex 1 (3.38 eV, 5.4 × 10-12 S cm-1).

3.
Chin Med J (Engl) ; 132(14): 1666-1672, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31268911

RESUMO

BACKGROUND: The detection of polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome at early stage is challenging for neurologists. Since polyneuropathy could be the first manifestation, it could be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP). The present study aimed to determine the clinical and electrophysiological features of POEMS syndrome to distinguish from CIDP. METHODS: The data of a group of patients with POEMS (n = 17) and patients with CIDP (n = 17) in Zhongshan Hospital Fudan University from January 2015 to September 2017 were analyzed in this retrospective study. The clinical features, neurological symptoms, and electrophysiological findings were compared between the two groups. RESULTS: Clinically, patients with POEMS demonstrated significantly more neuropathic pain in the lower extremities than patients with CIDP (58.8% vs. 11.8%, P = 0.01). Multisystem features like edema, skin change, organomegaly, and thrombocytosis were also pointed towards the diagnosis of POEMS syndrome. Electrophysiologically, terminal latency index (TLI) was significantly higher in patients with POEMS than that in patients with CIDP (median nerve: 0.39 [0.17-0.52] vs. 0.30 (0.07-0.69), Z = -2.413, P = 0.016; ulnar nerve: 0.55 [0.23-0.78] vs. 0.42 [0.12-0.70], Z = -2.034, P = 0.042). Patients with POEMS demonstrated a higher frequency of absent compound muscle action potential of the tibial nerve (52.9% vs. 17.6%, P = 0.031), less conduction block (ulnar nerve: 0 vs. 35.3%, P = 0.018), and less temporal dispersion (median nerve: 17.6% vs. 58.8%, P = 0.032) than CIDP group. The combination of positive serum monoclonal protein and high TLI (if either one or both were present) discriminated POEMS from CIDP with a sensitivity of 94.1% and 47.1% and specificity of 76.5% and 100.0%, respectively. CONCLUSIONS: POEMS syndrome could be distinguished from CIDP through typical clinical and electrophysiological characteristics in practice. The combination of serum monoclonal protein and high TLI might raise the sensitivity of detecting POEMS syndrome.


Assuntos
Síndrome POEMS/diagnóstico , Polineuropatias/diagnóstico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Idoso , Eletrofisiologia , Feminino , Humanos , Masculino , Nervo Mediano/fisiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Anormalidades da Pele/diagnóstico , Nervo Ulnar/fisiologia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117239, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31202031

RESUMO

A novel fluorescent graft conjugated polymer (poly (2, 5-bis (Polyethylene glycol oxybutyrate)-1, 4-phenylethynylene-alt-1, 4-phenyleneethynylene, PPE-OB-PEG) has been designed and synthesized for the determination of aristolochic acid (AA). The detection conditions and detection characters of PPE-OB-PEG were systematically explored in this work. The fluorescence intensity of PPE-OB-PEG changes with the different concentration of AA. PPE-OB-PEG has a good linear range towards AA from 1.00 × 10-7 to 8.00 × 10-5 mol L-1 and the limit of detection (LOD) is 3.00 × 10-8 mol L-1 (S/N = 3). PPE-OB-PEG have been applied to detect AA in traditional Chinese medicine samples and the results are satisfactory. The experimental results show that PPE-OB-PEG can be used as a fluorescence probe for rapid and sensitive detection of AA.


Assuntos
Alquinos/química , Ácidos Aristolóquicos/análise , Medicamentos de Ervas Chinesas/química , Éteres/química , Corantes Fluorescentes/química , Polietilenoglicóis/química , Espectrometria de Fluorescência/economia , Espectrometria de Fluorescência/métodos , Fatores de Tempo
5.
Inorg Chem ; 58(13): 8500-8505, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247843

RESUMO

Metal halide perovskites have fascinating electronic properties and have already been implemented in various devices. Although the behavior of the properties of lead halide perovskite nanocrystals has been studied, the properties of lead-free perovskite nanocrystals are less well-understood because synthesizing them is still very challenging. Here, a simple and popularizable method has been demonstrated to grow monodisperse bismuth-halide double perovskite nanocrystals, Cs2AgBiBr6 (1), inside three kinds of mesoporous silica templates. The size and morphology of nanocrystals depend on the structure and pore size of the template. Structural analysis shows that the nanocrystals of various sizes and morphologies retain the crystal structure of bimetallic perovskite. 1 exhibits different morphologies in the silicon channels of three templates: square nanoparticles in KIT-6, spherical and rodlike particles in SBA-15, and nanowires in MCM-41. UV-vis-NIR and photoluminescence measurements show us the variation of band gap and carrier recombination time due to quantum confinement of nanocrystals in mesoporous silicon materials. The band gaps of nanocrystals in the template exhibit an obvious blue shift compared with that of the bulk sample, and the carrier recombination time is significantly shortened. We show that mesoporous silicon templates can be used to prepare lead-free perovskite nanocrystals, and the controllable preparation of nanocrystals can be achieved by the template's own characteristics. This provides a new idea for us to find new functional materials of lead-free metal halide solid-state light-emitting diodes.

6.
Dalton Trans ; 47(30): 10124-10129, 2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30003204

RESUMO

Four unprecedented decanuclear heterometallic [Ln2CoII4CoIII4] clusters based on a diethanolamine ligand (H2dea), namely [Eu2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·4CH3OH·2H2O (1), [Gd2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·4CH3OH·2H2O (2), [Tb2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·2CH3OH·4H2O (3) and [Dy2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·2CH3OH·4H2O (4) were synthesized through a facile solution method. Single-crystal X-ray diffraction analyses reveal that complexes 1-4 consist of a [Ln2CoII4CoIII4] core, which is constructed by bridging a quasi-double cuboidal [Ln2CoII2CoIII2] core with two [CoIICoIII] units. Electrospray ionization mass spectrometry (ESI-MS) using methanol solution reveals that complexes 1-4 are stable in the solution, and the clusters undergo three different substitution reactions (Cl- replaced by OH-, OH- replaced by CH3O- and HCOO- replaced by OH-/CH3O-) at the same time in the ionization state. Magnetic susceptibilities reveal ferromagnetic couplings within complexes 3 and 4, and the magnetocaloric effect (MCE) for 2 was also evaluated and the maximum entropy change (-ΔSm) value reaches 16.3 J kg-1 K-1 at about 3 K and 5 T.

7.
Talanta ; 187: 314-320, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29853053

RESUMO

A novel fluorescent conjugated polymer (poly(2-amino-N-(2-((4-ethynylphenyl) ethynyl) phenyl)-5-guanidinopentanamide)-1,4-phenylethynylene-1,4-phenyleneethynylene, PPE-Arg) was synthesized in this paper. We found that PPE-Arg could be quenched by picric acid (PA). Photoinduced electron transfer (PET) mechanism can be used to describe the fluorescence quenching of PPE-Arg. It could be speculated that the photo-induced electrons may be transferred from PPE-Arg to nitroaromatic explosives. In this paper, the experiment conditions and detection performance of PPE-Arg were systematically studied. The experiment results demonstrate PPE-Arg as a sensor for PA has a good linear range from 5 × 10-7 to 6 × 10-5 mol L-1 with the calculated limit of detection (LOD) to be 1.0 × 10-7 mol L-1. Meanwhile, reaction time between PPE-Arg and PA is less than 1 min. This proposed sensor was applied to rapidly detect nitroaromatic explosives in environmental water samples and satisfactory results were obtained.

8.
Medicine (Baltimore) ; 96(44): e8473, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29095302

RESUMO

RATIONALE: Spontaneous spinal epidural hematoma (SSEH) is a relatively rare but potentially disabling disease, and the classical presentation of it includes an acute onset of severe, sometimes radiating back or neck pain, followed by signs and symptoms of rapidly evolving nerve root or spinal cord compression. PATIENT CONCERNS: Here, we report a 26-year-old female patient presented with weakness in bilateral lower extremities, progressing to intense paraplegia and anesthesia without recent medical history of trauma, infection, surgery, or drug use. DIAGNOSIS: A magnetic resonance imaging (MRI) scan of spinal cord was planned and a posterior epidural hematoma of the thoracic spine was observed. INTERVENTIONS: A posterior decompression and hematoma evacuation was performed after diagnosis immediately. Early rehabilitation program of the specific kind spinal cord injury was formulated and implemented. OUTCOMES: The patient finally can handle basic living activities, such as completing wheelchair locomotion, transferring from bed to wheelchair independently after 3 months of rehabilitation. LESSONS: SSEH is a rarely occurring case in emergency. Acute chest pain and paraplegia could be the initial presentation of acute spinal epidural hemorrhage, but the diagnosis of patient without classical manifestations is still a challenge for doctors. Early diagnosis, prompt decompression, and individualized rehabilitation program can improve the prognosis and outcome.


Assuntos
Descompressão Cirúrgica/reabilitação , Hematoma Epidural Espinal/reabilitação , Atividades Cotidianas , Adulto , Descompressão Cirúrgica/métodos , Feminino , Hematoma Epidural Espinal/complicações , Hematoma Epidural Espinal/cirurgia , Humanos , Paraplegia/etiologia , Paraplegia/reabilitação , Paresia/etiologia , Paresia/reabilitação , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Cadeiras de Rodas
9.
Food Chem ; 232: 198-202, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490065

RESUMO

A novel hollow fiber membranes-based dynamic liquid-liquid micro-extraction (HF-DLLME) coupled with HPLC-UV detection has been developed for the residue analysis of tetracyclines in milk samples without deproteinization and degreasing. The influences of experimental parameters were investigated and optimized. The method showed a good performance. The limits of detection (LOD) are in the range of 0.95-3.6µg/L. The recoveries in spiked samples range from 92.38 to 107.3%. The relative standard deviations (RSDs) are lower than 8.66%. The advantages of this method are simple operation, high efficiency, absence of sample carryover and low cost.


Assuntos
Leite , Tetraciclinas , Animais , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Contaminação de Alimentos , Microextração em Fase Líquida , Extração Líquido-Líquido
10.
Sci Rep ; 6: 25251, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27143630

RESUMO

The clinical and mycobacterial features of tuberculous meningitis (TBM) cases in China are not well described; especially in western provinces with poor tuberculosis control. We prospectively enrolled patients in whom TBM was considered in Shaanxi Province, northwestern China, over a 2-year period (September 2010 to December 2012). Cerebrospinal fluid specimens were cultured for Mycobacterium tuberculosis; with phenotypic and genotypic drug susceptibility testing (DST), as well as genotyping of all positive cultures. Among 350 patients included in the study, 27 (7.7%) had culture-confirmed TBM; 84 (24.0%) had probable and 239 (68.3%) had possible TBM. DST was performed on 25/27 (92.3%) culture positive specimens; 12/25 (48.0%) had "any resistance" detected and 3 (12.0%) were multi-drug resistant (MDR). Demographic and clinical features of drug resistant and drug susceptible TBM cases were similar. Beijing was the most common genotype (20/25; 80.0%) with 9/20 (45%) of the Beijing strains exhibiting drug resistance; including all 3 MDR strains. All (4/4) isoniazid resistant strains had mutations in the katG gene; 75% (3/4) of strains with phenotypic rifampicin resistance had mutations in the rpoB gene detected by Xpert MTB/RIF®. High rates of drug resistance were found among culture-confirmed TBM cases; most were Beijing strains.


Assuntos
Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Catalase/genética , Líquido Cefalorraquidiano/microbiologia , Criança , Pré-Escolar , China/epidemiologia , RNA Polimerases Dirigidas por DNA/genética , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Tuberculose Meníngea/epidemiologia , Adulto Jovem
11.
Int J Neurosci ; 126(11): 989-95, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26514341

RESUMO

AIMS: To assess the effectiveness of delayed surgery and follow-up observation in managing severe Bell's palsy after two months of onset. METHODS: Forty-one Bell's palsy patients with severe facial paralysis were treated after two months of onset. Eighteen patients in group I underwent decompression operations between two and three months after onset, and eight patients in group II underwent surgery after three months of onset; 15 patients in group III were managed with follow-up observation. All patients were followed up at the end of 3rd, 6th and 12th months, and surgical outcomes were compared with follow-up observations using House-Brackmann score and Facial Clinimetric Evaluation (FaCE) scale. RESULTS: Between groups I and III, the difference in the proportion of the patients with fair or poor recoveries was statistically significant (p < 0.05) at the three-month follow-up visit. There was no significant difference in the distribution of complete, fair or poor recoveries at the 12-month follow-up visits among the three groups (p < 0.05). The total FaCE score and five individual domains were significantly improved at the end of the follow-up period in groups I and III (p < 0.05). However, in group I, the lacrimal control scores were significantly decreased at the end of the follow-up period compared to scores before surgery (p < 0.05). After surgery, four patients had sensorineural hearing loss, three patients had tinnitus and no patients had vertigo. CONCLUSION: Patients with severe Bell's palsy after two months of onset would not benefit from delayed decompression surgery.


Assuntos
Paralisia de Bell/cirurgia , Descompressão Cirúrgica/métodos , Adulto , Descompressão Cirúrgica/normas , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
12.
Front Microbiol ; 7: 2096, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28082963

RESUMO

Background: Microbiological confirmation of tuberculous meningitis (TBM) remains problematic. We assessed the diagnostic performance of a modified Ziehl-Neelsen (MZN) staining method that showed promise in earlier studies. Methods: Patients evaluated for TBM in Shaanxi province, China, were prospectively enrolled from May, 2011 to April, 2013. Cerebrospinal fluid (CSF) specimens were evaluated using the Xpert MTB/RIF® assay, MZN staining, and standard biochemical and microbiological tests, together with detailed clinical and radiological assessment. Results: Among 316 patients included in the study, 38 had definite TBM, 66 probable TBM, 163 possible TBM and 49 "no TBM," using consensus uniform research case definition criteria. Comparing "definite or probable TBM" to "no TBM" MZN staining had higher sensitivity than Xpert MTB/RIF® (88.5 vs. 36.5%), but greatly reduced specificity (71.4 vs. 100.0%); 14/49 (28.6%) cases with "no TBM" tested positive on MZN. Mycobacterium tuberculosis culture was performed in 104/179 (58.1%) of MZN positive samples; 12.5% (13/104) were positive. Using Xpert MTB/RIF® as the reference standard, MZN had a sensitivity of 92.1% (95% CI 79.2-97.3) and specificity of 71.4% (95% CI 57.6-82.2). Conclusion: Xpert MTB/RIF® offered a rapid and specific TBM diagnosis, but sensitivity was poor. MZN was mainly hampered by false positives. Strategies to enhance the sensitivity of Xpert MTB/RIF® or improve the diagnostic accuracy of MZN should be explored.

13.
Int J Clin Exp Pathol ; 8(11): 14457-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26823763

RESUMO

Multiple animal models of experimental autoimmune myositis (EAM) have been developed. However, these models vary greatly in the severity of disease and reproducibility. The goal of this study was to test whether vaccination twice with increased dose of rat myosin and pertussis toxin (PT) could induce EAM with severer disease in mice. BALB/c mice were injected with 1 mg rat myosin in 50% complete Freund's adjuvant (CFA) weekly for four times and one time of PT (EAM) or twice with 1.5 mg myosin in CFA and PT (M-EAM). In comparison with that in the CFA and PT injected controls, vaccination with rat myosin and injection PT significantly reduced the muscle strength and EMG duration, elevated serum creatine kinase levels, promoted inflammatory infiltration in the muscle tissues, leading to pathological changes in the muscle tissues, demonstrating to induce EAM. Interestingly, we found that vaccination twice with the high dose of myosin and PT prevented EAM-related gain in body weights and caused significantly less muscle strength in mice. More importantly, all of the mice receiving high dose of myosin and PT survived while 3 out of 16 mice with four times of low dose of myosin died. Finally, vaccination with high dose of myosin promoted CD4(+) and CD8(+) T cell infiltration in the muscle tissues and up-regulated MHC-I expression in the muscle tissues of mice. Hence, the new model of EAM is a time-saving, efficient and easily replicable tool for studying autoimmune myositis.


Assuntos
Miosinas , Doença Autoimune do Sistema Nervoso Experimental/induzido quimicamente , Toxina Pertussis , Animais , Biomarcadores/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiotaxia de Leucócito , Creatina Quinase Forma MM/sangue , Progressão da Doença , Feminino , Cobaias , Camundongos Endogâmicos BALB C , Força Muscular , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Doença Autoimune do Sistema Nervoso Experimental/sangue , Doença Autoimune do Sistema Nervoso Experimental/imunologia , Doença Autoimune do Sistema Nervoso Experimental/patologia , Doença Autoimune do Sistema Nervoso Experimental/fisiopatologia , Fenótipo , Índice de Gravidade de Doença , Fatores de Tempo , Ganho de Peso
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1671-4, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25358185

RESUMO

The microwave plasma torch (MPT) was used as the emission light source. Aqueous samples were introduced with a nebulizer and a desolvation system. A method for the determination of Na, Mg, Ca, Li and Sr in natural mineral drinking water by argon microwave plasma torch spectrometer (ArMPT spectrometer) was established. The effects of microwave power, flow rate of carrier gas and support gas were investigated in detail and these parameters were optimized. Under the optimized condition, the experiments for the determination of Na, Mg, Ca, Li and Sr in 11 kinds of bottled mineral drinking water were carried out by ArMPT spectrometer. The limit-of-detection (LOD) of Na, Mg, Ca, Li and Sr was found to be 4.4, 21, 56, 11 and 84 µg x mL(-1), respectively. Relative standard deviation (n = 6) was in the range of 1.30%-5.45% and standard addition recoveries were in the range of 84.6%-98.5%. MPT spectrometer was simpler, more convenient and of lower cost as compared to ICP unit. MPT spectrometer demonstrated its rapid analysis speed, accuracy, sensitivity and simultaneous multi element analysis ability during the analysis process. The results showed that MPT spectrometer was suitable for metal elements detection for natural mineral drinking water. This approach provides not only one way for resisting the illegal dealings, but also a security for the quality of drinking water. Moreover, the usability of MPT spectrometer in the field of food security; drug safety; clinical diagnostic is promised.


Assuntos
Água Potável/análise , Águas Minerais/análise , Cálcio , Lítio , Magnésio , Micro-Ondas , Sódio , Análise Espectral , Estrôncio
15.
Biomed Res Int ; 2014: 854954, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24791002

RESUMO

B cell activating factor (BAFF) is a cytokine of tumor necrosis factor family mainly produced by monocytes and dendritic cells. BAFF can regulate the proliferation, differentiation, and survival of B lymphocytes by binding with BAFF-R on B cell membrane. Accumulating evidences showed that BAFF played crucial roles and was overexpressed in various autoimmune diseases such as systemic lupus erythematous (SLE) and rheumatoid arthritis (RA). This suggests that BAFF may be a therapeutic target for these diseases. In the present study, we developed a BAFF therapeutic vaccine by coupling a T helper cell epitope AKFVAAWTLKAA (PADRE) to the N terminus of BAFF extracellular domains (PADRE-BAFF) and expressed this fusion protein in Escherichia coli. The purified vaccine can induce high titer of neutralizing BAFF antibodies and ameliorate the syndrome of complete Freund's adjuvant (CFA) induced rheumatoid arthritis in rats. Our data indicated that the BAFF autovaccine may be a useful candidate for the treatment of some autoimmune diseases associated with high level of BAFF.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/imunologia , Autovacinas/uso terapêutico , Fator Ativador de Células B/imunologia , Epitopos de Linfócito T/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Animais , Anticorpos/sangue , Artrite Experimental/metabolismo , Artrite Experimental/fisiopatologia , Autovacinas/genética , Autovacinas/imunologia , Autovacinas/metabolismo , Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo
16.
Mol Neurobiol ; 50(3): 997-1012, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24510312

RESUMO

Our recent studies demonstrated that mature astrocytes from spinal cord can be reprogrammed in vitro and in vivo to generate neural stem/progenitor cells (NSPCs) following treatment with conditioned medium collected from mechanically injured astrocytes. However, little is known regarding the molecular mechanisms underlying the reprogramming of astrocytes. Here, we show that fibroblast growth factor 4 (FGF4) exerts a critical role in synergistically converting astrocytes into NSPCs that can express multiple neural stem cell markers (nestin and CD133) and are capable of both self-renewal and differentiation into neurons and glia. Lack of FGF4 signals fails to elicit the dedifferentiation of astrocytes towards NSPCs, displaying a substantially lower efficiency in the reprogramming of astrocytes and a slower transition through fate-determined state. These astrocyte-derived NSPCs displayed relatively poor self-renewal and multipotency. More importantly, further investigation suggested that FGF4 is a key molecule necessary for activating PI3K/Akt/p21 signaling cascades, as well as their downstream effectors responsible for directing cell reprogramming towards NSPCs. Collectively, these findings provide a molecular basis for astrocyte dedifferentiation into NSPCs after central nervous system (CNS) injury and imply that FGF4 may be a clinically applicable molecule for in situ neural repair in the CNS disorders.


Assuntos
Astrócitos/metabolismo , Desdiferenciação Celular/fisiologia , Fator 4 de Crescimento de Fibroblastos/metabolismo , Células-Tronco Neurais/metabolismo , Medula Espinal/metabolismo , Animais , Astrócitos/citologia , Proliferação de Células , Células Cultivadas , Fator 4 de Crescimento de Fibroblastos/genética , Células-Tronco Neurais/citologia , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/citologia
17.
Am J Respir Crit Care Med ; 189(4): 475-81, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24450377

RESUMO

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.


Assuntos
Antígenos de Bactérias/líquido cefalorraquidiano , Proteínas de Bactérias/líquido cefalorraquidiano , Leucócitos/microbiologia , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Estudos Prospectivos , Sensibilidade e Especificidade , Coloração e Rotulagem , Tuberculose Meníngea/líquido cefalorraquidiano , Adulto Jovem
19.
Artigo em Chinês | MEDLINE | ID: mdl-24016567

RESUMO

OBJECTIVE: To assess the effectiveness and safety of intratympanic versus systemic steroid therapy in the initial treatment of idiopathic sudden hearing loss. METHODS: An extensive search of the literature was performed in Pubmed and other available database from January, 1980 to November, 2011. After filtering by the criteria of Cochrane Collaboration, a meta-analysis was conducted. RESULTS: Nine studies met the criteria for meta-analysis, for idiopathic sudden hearing loss patients without diabetes received intratympanic steroid therapy, the improvement rate (RR = 1.11,95% CI = 0.96-1.28, P = 0.15) did not show any significance when compared with the patients received systemic therapy. While a significant difference of improvement rate occurred between intratympanic and systemic steroid therapy in the idiopathic sudden hearing loss patients with diabetes (RR = 1.24, 95% CI = 1.02-1.50, P = 0.03). CONCLUSION: For the initial therapy of idiopathic sudden hearing loss patients without diabetes, systemic steroid treatment still remains the first choice, but for the idiopathic sudden hearing loss patients with diabetes, intratympanic steroid treatment should be used for the initial treatment.


Assuntos
Perda Auditiva Súbita/tratamento farmacológico , Esteroides/uso terapêutico , Administração Oral , Audiometria de Tons Puros , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Perda Auditiva Neurossensorial/tratamento farmacológico , Humanos , Metilprednisolona , Esteroides/administração & dosagem , Resultado do Tratamento , Membrana Timpânica
20.
Artigo em Chinês | MEDLINE | ID: mdl-23656809

RESUMO

OBJECTIVE: To explore the health related quality of life (QOL) status of patients with peripheral facial paralysis. METHODS: By introducing, translating and adjusting of the FaCE (Facial Clinimetric Evaluation) scale, a Chinese version came into being. The scale was further strictly tested in eighty-one patients with peripheral facial paralysis and thirty healthy volunteers. RESULTS: The feasibility, reliability, validity and responsibility of Chinese version of FaCE scale all passed the test. The split-half reliability, Cronbach's alpha and intraclass correlation coefficient were 0.79, 0.88 and 0.87, respectively. The criteria validity calculated between FaCE and SF-36 was 0.41 (P < 0.05). Factor analysis of the construct validity showed that the 15 items were classified into six domains, which were in accordance with the original version. Every domain was sensitive and effective to discriminate between patient population and healthy population (P < 0.05). Chinese version of FaCE scale showed significant correlation with HBGS and SBGS scores (r = -0.40 and 0.42, P < 0.05). CONCLUSION: Chinese version of the FaCE scale can effectively assess QOL status of patients with facial paralysis in China.


Assuntos
Paralisia Facial , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem
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