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1.
Exp Ther Med ; 18(5): 3737-3740, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31656537

RESUMO

Intellectual disability (ID) is a non-specific phenotype present in a genetically heterogeneous group of disorders. The genetic cause of ID remains elusive in the majority of patients due to this extreme heterogeneity. Whole exome sequencing technology has been applied to identify pathogenic gene variants responsible for ID. The present report described a 1.7-year-old female patient who had severe ID with the specific features of delayed motor development, language disorders and abnormal facial features. Exome analysis identified a novel pathogenic variant of the SETD5 gene [c.2025_2026delAG (p.Gly676Valfs*2)]. The variant was a frameshift mutation, causing termination of the protein in advance. These findings indicated that this mutation of the SETD5 gene may be a genetic cause for ID. The present study aimed to provide a meaningful exploration of ID and the identification of clinical core genetic pedigrees.

2.
Turk Pediatri Ars ; 54(2): 125-128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384148

RESUMO

Teratoma is a rare tumor of the central nervous system that belongs to intracranial germ cell tumors. We report a 2-month-old male child with an immature teratoma of the posterior fossa. Physical and laboratory examinations were normal. Though a radiologic examination was characteristic for this neoplasm, it was insufficient to make a definite diagnosis. Combining the radiologic findings with a histopathologic examination contributed to diagnosing immature teratoma and differentiating it from other subtypes of intracranial germ cell tumors. Our aim was to provide a greater understanding of immature teratoma by reporting this case.

3.
Biomed Res Int ; 2019: 9105768, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016203

RESUMO

Objectives: The aim of this study was to evaluate the effects of bone marrow stromal stem cells (BMSCs) on renal ischemia-reperfusion injury (RIRI) and dynamically monitor engrafted BMSCs in vivo for the early prediction of their therapeutic effects in a rat model. Methods: A rat model of RIRI was prepared by clamping the left renal artery for 45 min. One week after renal artery clamping, 2 × 106 superparamagnetic iron oxide- (SPIO-) labeled BMSCs were injected into the renal artery. Next, MR imaging of the kidneys was performed on days 1, 7, 14, and 21 after cell transplantation. On day 21, after transplantation, serum creatinine (Scr) and urea nitrogen (BUN) levels were assessed, and HE staining and TUNEL assay were also performed. Results: The body weight growth rates in the SPIO-BMSC group were significantly higher than those in the PBS group (P < 0.05), and the Scr and BUN levels were also significantly lower than those in the PBS group (P < 0.05). HE staining showed that the degree of degeneration and vacuole-like changes in the renal tubular epithelial cells in the SPIO-BMSC group was significantly better than that observed in the PBS group. The TUNEL assay showed that the number of apoptotic renal tubular epithelial cells in the SPIO-BMSC group was significantly lower than that in the PBS group. The T2 value of the renal lesion was the highest on day 1 after cell transplantation, and it gradually decreased with time in both the PBS and SPIO-BMSC groups but was always the lowest in the SPIO-BMSC group. Conclusion: SPIO-labeled BMSC transplantation can significantly promote the recovery of RIRI and noninvasive dynamic monitoring of engrafted cells and can also be performed simultaneously with MRI in vivo for the early prediction of therapeutic effects.


Assuntos
Células da Medula Óssea/citologia , Rim/patologia , Células-Tronco Mesenquimais/citologia , Traumatismo por Reperfusão/patologia , Animais , Meios de Contraste/administração & dosagem , Modelos Animais de Doenças , Feminino , Imagem por Ressonância Magnética/métodos , Nanopartículas de Magnetita/administração & dosagem , Transplante de Células-Tronco Mesenquimais/métodos , Ratos , Ratos Sprague-Dawley , Artéria Renal/patologia , Coloração e Rotulagem/métodos
4.
Ital J Pediatr ; 45(1): 37, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30867013

RESUMO

BACKGROUND: Neural tube defects (NTDs) are birth defects of the brain, spine, or spinal cord invoked by the insufficient intake of folic acid in the early stages of pregnancy and have a complex etiology involving both genetic and environmental factors. So the study aimed to explore the association between alterations in maternal one-carbon metabolism and NTDs in the offspring. METHODS: We conducted a case-control study to get a deeper insight into this association, as well as into the role of genetic polymorphisms. Plasma concentrations of folate, homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH) and genotypes and alleles distributions of 52 SNPs in 8 genes were compared for 61 women with NTDs-affected offspring and 61 women with healthy ones. RESULTS: There were significant differences between groups with regard to plasma folate, SAM, SAH and SAM/SAH levels. Logistic regression results revealed a significant association between maternal plasma folate level and risk of NTDs in the offspring. For MTHFD1 rs2236225 polymorphism, mothers having GA genotype and A allele exhibited an increased risk of NTDs in the offspring (OR = 2.600, 95%CI: 1.227-5.529; OR = 1.847, 95%CI: 1.047-3.259). For MTHFR rs1801133 polymorphism, mothers having TT and CT genotypes were more likely to affect NTDs in the offspring (OR = 4.105, 95%CI: 1.271-13.258; OR = 3.333, 95%CI: 1.068-10.400). Moreover, mothers carrying T allele had a higher risk of NTDs in the offspring (OR = 1.798, 95%CI: 1.070-3.021). For MTRR rs1801394 polymorphism, the frequency of G allele was significantly higher in cases than in controls (OR = 1.763, 95%CI: 1.023-3.036). Mothers with NTDs-affected children had higher AG genotype in RFC1 rs1051226 polymorphism than controls, manifesting an increased risk for NTDs (OR = 3.923, 95%CI: 1.361-11.308). CONCLUSION: Folic acid deficiency, MTHFD1 rs2236225, MTHFR rs1801133, MTRR rs1801349 and RFC1 rs1051226 polymorphisms may be maternal risk factors of NTDs.


Assuntos
Deficiência de Ácido Fólico/genética , Predisposição Genética para Doença/epidemiologia , Defeitos do Tubo Neural/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Carbono/metabolismo , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , China , Feminino , Ferredoxina-NADP Redutase/genética , Deficiência de Ácido Fólico/diagnóstico , Deficiência de Ácido Fólico/epidemiologia , Marcadores Genéticos/genética , Genótipo , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Antígenos de Histocompatibilidade Menor/genética , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/fisiopatologia , Razão de Chances , Gravidez , Valores de Referência
5.
Pediatr Neurosurg ; 53(6): 401-406, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30391955

RESUMO

Choroid plexus papilloma (CPP) is a rare benign tumor of the central nervous system. Bilateral lateral ventricle CPP is extremely uncommon. In this case report, we described a case of bilateral lateral ventricle CPP in a 4-month-old female patient conceived by in vitro fertilization (IVF). Neurological examination and imaging were performed. In neurological examination, meningeal irritation signs and sunset phenomenon were positive. Brain computed tomography (CT) and magnetic resonance imaging (MRI) displayed masses located in the trigone of the bilateral lateral ventricle with hydrocephalus. Contrast-enhanced MRI showed intense homogeneous enhancement. The diagnoses of bilateral lateral ventricle CPP related to hydrocephalus and extravasation of cerebrospinal fluid (CSF) were made. Repeated surgical procedures via parietotemporal craniotomy were performed, and the diagnosis was confirmed by histopathology examination. The patient presented with delayed development during a follow-up period of 1 year. In conclusion, imaging is an effective approach of investigation. CPP could be highly suspected according to the features of hydrocephalus, lobulated appearance, and homogeneous enhancement on imaging. Total surgical removal is a valid curative method for CPP.


Assuntos
Neoplasias do Ventrículo Cerebral/cirurgia , Ventrículos Laterais/diagnóstico por imagem , Ventrículos Laterais/patologia , Papiloma do Plexo Corióideo/diagnóstico por imagem , Papiloma do Plexo Corióideo/patologia , Neoplasias do Ventrículo Cerebral/patologia , Feminino , Fertilização In Vitro , Humanos , Hidrocefalia/líquido cefalorraquidiano , Hidrocefalia/patologia , Hidrocefalia/cirurgia , Lactente , Ventrículos Laterais/cirurgia , Imagem por Ressonância Magnética , Papiloma do Plexo Corióideo/cirurgia , Tomografia Computadorizada por Raios X
6.
Int J Nanomedicine ; 13: 1749-1759, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29606868

RESUMO

Background: Melanin and manganese are both indispensable natural substances that play crucial roles in the human body. Melanin has been used as a multimodality imaging nanoplatform for biology science research because of its natural binding ability with metal ions (eg, 64Cu2+, Fe3+, and Gd3+). Because of its effects on T1 signal enhancement, Mn-based nanoparticles have been used in magnetic resonance (MR) quantitative cell tracking in vivo. Stem cell tracking in vivo is an essential technology used to characterize engrafted stem cells, including cellular viability, biodistribution, differentiation capacity, and long-term fate. Methods: In the present study, manganese(II) ions chelated to melanin nanoparticles [MNP-Mn(II)] were synthesized. The characteristics, stem cell labeling efficiency, and cytotoxicity of the nanoparticles were evaluated. MR imaging of the labeled stem cells in vivo and in vitro were also further performed. In T1 relaxivity (r1), MNP-Mn(II) were significantly more abundant than Omniscan. Bone marrow-derived stem cells (BMSCs) can be labeled easily by coincubating with MNP-Mn(II), suggesting that MNP-Mn(II) had high biocompatibility. Results: Cell Counting Kit-8 assays revealed that MNP-Mn(II) had almost no cytotoxicity when used to label BMSCs, even with a very high concentration (1,600 µg/mL). BMSCs labeled with MNP-Mn(II) could generate a hyperintense T1 signal both in vitro and in vivo, and the hyperintense T1 signal in vivo persisted for at least 28 days. Conclusion: Taken together, our results showed that MNP-Mn(II) possessed many excellent properties for potential quantitative stem cell tracking in vivo.


Assuntos
Imagem por Ressonância Magnética/métodos , Manganês/química , Melaninas/química , Nanopartículas/química , Células-Tronco/citologia , Animais , Materiais Biocompatíveis/química , Diferenciação Celular , Quelantes/química , Masculino , Nanopartículas/uso terapêutico , Ratos Sprague-Dawley , Distribuição Tecidual
7.
J Biomed Mater Res A ; 105(1): 131-137, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27588709

RESUMO

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium3+ (Gd3+ )-chelate nanoparticles (MNP-Gd3+ ) of ∼7 nm for stem cell tracking in vivo. MNP-Gd3+ possesses many beneficial properties, such as its high stability and sensitivity, shorter T1 relaxation time, higher cell labeling efficiency, and lower cytotoxicity compared with commercial imaging agents. We found that the T1 relaxivity (r1 ) of MNP-Gd3+ was significantly higher than that of Gd-DTPA; the nanoparticles were taken up by bone mesenchymal stem cells (BMSCs) via endocytosis and were broadly distributed in the cytoplasm. Based on an in vitro MTT assay, no cytotoxicity of labeled stem cells was observed for MNP-Gd3+ concentrations of less than 800 µg/mL. Furthermore, we tracked MNP-Gd3+ -labeled BMSCs in vivo using 3.0T MRI equipment. After intramuscular injection, MNP-Gd3+ -labeled BMSCs were detected, even after four weeks, by 3T MRI. We concluded that MNP-Gd3+ nanoparticles at appropriate concentrations can be used to effectively monitor and track BMSCs in vivo. MNP-Gd3+ nanoparticles have potential as a new positive MRI contrast agent in clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 131-137, 2017.


Assuntos
Células da Medula Óssea/citologia , Rastreamento de Células/métodos , Meios de Contraste , Gadolínio , Imagem por Ressonância Magnética/métodos , Melaninas , Células-Tronco Mesenquimais/citologia , Nanopartículas , Animais , Células da Medula Óssea/metabolismo , Meios de Contraste/química , Meios de Contraste/farmacologia , Gadolínio/química , Gadolínio/farmacologia , Teste de Materiais , Melaninas/química , Melaninas/farmacologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Nanopartículas/uso terapêutico , Ratos , Ratos Sprague-Dawley
8.
Yao Xue Xue Bao ; 51(3): 444-9, 2016 03.
Artigo em Chinês | MEDLINE | ID: mdl-29859027

RESUMO

The study aims to develop a rapid, specific and sensitive method for quantitative analysis of trace impurities in levofloxacin formulation using LC-MS/MS. The quality of the different formulations from 19 plants was evaluated in the contents of the impurities. The results indicated that there were 5 impurities in the samples, and the content was different in the products with same formulation by different plants. The products of 3 plants were in good quality with impurities level under 0.01%. Levofloxacin N(4')-methyl quaternary impurity was first reported as the formulation impurity. The impurities were tightly correlated to the reservation of drug, process control of formulation and storage during transportation. The results suggest that our method is sensitive and specific to detect the trace impurities in formulation, and can be used to monitor the quality of commercial drug product.


Assuntos
Contaminação de Medicamentos , Levofloxacino/análise , Levofloxacino/normas , Cromatografia Líquida , Espectrometria de Massas em Tandem
9.
Yao Xue Xue Bao ; 51(10): 1564-71, 2016 10.
Artigo em Chinês | MEDLINE | ID: mdl-29932601

RESUMO

The research aimed to investigate the suppression effect of Mai Shu which contains hawthorn, hippophae, medlar, phytosterols(ß-sitosterol, stigmasterol and campesterol), ß-glucan and lycopeneon formation of atherosclerotic plaque in apolipoprotein E knock-out (ApoE-/-) mice. Liquid chromatography-ultravioletmass spectrometry(LC-UV-MC) methods were used to analyze the main chemical composition of Mai Shu. Atherosclerotic mice models were established by high-fat diet. The mice were administrated with Mai Shu (1, 2, 4 g·kg-1·d-1) or other contrast materials by intragastric route for 10 weeks continuously. At the end of administration, the blood of mice was collected for tests of the serum total cholesterol(TC), total triglyceride(TG) and high density lipoprotein cholesterol(HDL-C) level. Atherosclerotic lesions in aorta and aortic root were assessed by calculating the relative area of lesions(oil red O stained). Intravital fluorescence microscopic system was used to evaluate the leukocyte-endothelial adhesion in mesenteric artery of mice by detecting the rolling velocity of white blood cells(WBC). Collagenous fibers and macrophages in lesions were detected by sirius red staining and immunological histological chemistry to evaluate the atherosclerotic plaque stability. Results showed that Mai Shu contains various flavonoids(9.5%), phytosterols(23.8%) and polysaccharides(8.9%). The serum lipid level of model animals was significantly higher than the control animals. Serum TC level was decreased by Mai Shu (4 g·kg-1, P < 0.001) compared to the untreated model. Serum TG level was reduced by Mai Shu (1, 2, 4 g·kg-1) compared to model(P < 0.01). Area of atherosclerotic lesions in aorta and aortic root was decreased in Mai Shu group (aorta: 1 g·kg-1, P < 0.05; 2 g·kg-1, P < 0.01; 4 g·kg-1, P < 0.001; aortic root: 2, 4 g·kg-1, P < 0.01). Rolling velocity of white blood cells of Mai Shu (4 g·kg-1, P < 0.001) group was increased over the untreated model. Collagenous fibers in lesions were observationally increased by Mai Shu (1, 2 g·kg-1) and macrophages were decreased (2, 4 g·kg-1) compared to model. These results demonstrate that Mai Shu can obviously decrease the serum lipid levels and the risk of leukocyte-endothelial adhesion in ApoE-/- mice. The effect of Mai Shu may be associated with the decrease of macrophages in plaque.


Assuntos
Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Placa Aterosclerótica/tratamento farmacológico , Animais , Aorta/patologia , Colesterol/sangue , Dieta Hiperlipídica , Modelos Animais de Doenças , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Fitosteróis/farmacologia , Triglicerídeos/sangue
10.
Stem Cells Int ; 2016: 2018474, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26649047

RESUMO

Despite advances in our understanding of spinal cord injury (SCI) mechanisms, there are still no effective treatment approaches to restore functionality. Although many studies have demonstrated that transplanting NT3 gene-transfected bone marrow-derived mesenchymal stem cells (BMSCs) is an effective approach to treat SCI, the approach is often low efficient in the delivery of engrafted BMSCs to the site of injury. In this study, we investigated the therapeutic effects of magnetic targeting of NT3 gene-transfected BMSCs via lumbar puncture in a rat model of SCI. With the aid of a magnetic targeting cells delivery system, we can not only deliver the engrafted BMSCs to the site of injury more efficiently, but also perform cells imaging in vivo using MR. In addition, we also found that this composite strategy could significantly improve functional recovery and nerve regeneration compared to transplanting NT3 gene-transfected BMSCs without magnetic targeting system. Our results suggest that this composite strategy could be promising for clinical applications.

11.
Zhongguo Zhong Yao Za Zhi ; 40(5): 894-6, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26087552

RESUMO

A new sesquiterpenoid, 8α-hydroxy-6ß-methoxy-1-oxoeremophila-7 (11), 9 (10) -diene-12, 8-olide (1) and five known compounds, petasin (2), caffeic acid (3), hepta-cosanol (4), ß-sitosterol (5) and ß-daucosterol (6) have been isolated from the roots of Ligularia intermedia. The compounds were isolated by column chromatography on silica gel and Sephadex LH-20, and identified based on spectral analyses (MS, 1H-NMR, 13C-NMR).


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Imagem por Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
12.
Neural Regen Res ; 10(3): 404-11, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25878588

RESUMO

An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7-8. Superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesenchymal stem cells reached the lesion site in these rats than in those without magnetic guidance or superparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan (BBB) locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guidance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

13.
Acta Neurochir (Wien) ; 156(7): 1409-18, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24744011

RESUMO

BACKGROUND: This study aimed to investigate the therapeutic effects of transplanting neutrophin-3 (NT-3)-expressing bone marrow-derived mesenchymal stem cells (BMSCs) in a rat model of spinal cord injury (SCI). METHODS: Forty-eight adult female Sprague-Dawley rats were randomly assigned to three groups: the control, BMSC, and NT-3-BMSC groups. BMSCs were infected with NT-3-DsRed or DsRed lentivirus and injected into the cerebrospinal fluid (CSF) via lumbar puncture (LP) 7 days after SCI in the NT-3-BMSC and BMSC groups, respectively. The hind-limb motor function of all rats was recorded using the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale on days 1, 3, 7, 14, 21, 28, and 35 after transplantation. Haematoxylin-eosin (HE) staining, immunofluorescence labelling, and western blotting were performed at the final time point. RESULTS: Expressions of NT-3, brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor (VEGF) proteins increased significantly in the NT-3-BMSC group, and hind-limb locomotor functions improved significantly in the NT-3-BMSC group compared with the other two groups. The cystic cavity area was smallest in the NT-3-BMSC group. In the NT-3-BMSC group, neurofilament 200 (NF200) and glial fibrillary acidic protein (GFAP) expression levels around the lesions were significantly increased and decreased, respectively. CONCLUSIONS: Our findings demonstrate that transplantation of NT-3 gene-modified BMSCs via LP can strengthen the therapeutic benefits of BMSC transplantation. We observed that these modified cells increased locomotor function recovery, promoted nerve regeneration, and improved the injured spinal cord microenvironment, suggesting that it could be a promising treatment for SCI.


Assuntos
Transplante de Medula Óssea/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Traumatismos da Medula Espinal/terapia , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Membro Posterior/fisiopatologia , Locomoção , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Medula Espinal/patologia , Transfecção , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética
14.
Rapid Commun Mass Spectrom ; 28(10): 1164-74, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24711279

RESUMO

RATIONALE: Impurity analysis plays an important role to guarantee the quality and safety of pharmaceuticals. However, identification of impurities remains challenging, especially for those unknown or at trace levels. We present an integrated approach to detect and characterize the trace impurities in drugs. METHODS: Based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), an approach integrating automatic impurity screening method using multiple mass defect filters (MMDFs) and background subtraction (BS) was developed. This approach was used to acquire the structural and semi-quantitative information in a single sample run, and even to discover the impurity signals submerged by background and drug ions. This approach was illustrated by the comprehensive impurity analysis of levofloxacin. RESULTS: This approach was sensitive to detect impurities at the level of 0.02% with respect to levofloxacin concentration. Nineteen impurities were detected, fourteen of which were structurally characterized and eight impurities were reported for the first time. Impurity profiles of levofloxacin drug substances and degradation samples were obtained reliably. A plausible degradation pathway of levofloxacin was proposed including descarboxyl reaction under acid, piperazinyl ring cleavage degradation under light, and N-oxidation under oxidative condition. CONCLUSIONS: The generic approach integrating LC-MS/MS and an automatic impurity screening method was developed for the detection, characterization and monitoring of impurities, especially those unknown or at trace levels. This approach was demonstrated to be rapid, sensitive and automatic for impurity profiling of drugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Levofloxacino/análise , Levofloxacino/química , Espectrometria de Massas em Tandem/métodos , Contaminação de Medicamentos , Espectrometria de Massas por Ionização por Electrospray/métodos
15.
J Soc Psychol ; 153(5): 560-76, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24003583

RESUMO

Workers with high levels of role stressors have been known to report low job satisfaction and high turnover intention. However, how the role stressors-job attitudes relationship is influenced by leader-member exchange has hardly been studied. This study examined the effect of leader-member exchange (leader support) on the relationship between chronic role stressors (i.e., role ambiguity and role conflict) and job attitudes (i.e., job satisfaction and turnover intention). Employees (N = 162) who enrolled in weekend psychology courses were investigated. The results showed that leader-member exchange mediated the effects of role stressors on job satisfaction and turnover intention. Implications of these results are discussed and directions for future research are suggested.


Assuntos
Emprego/psicologia , Relações Interpessoais , Modelos Psicológicos , Papel (figurativo) , Estresse Psicológico/psicologia , Adulto , Atitude , Feminino , Humanos , Intenção , Liderança , Masculino , Satisfação Pessoal , Reorganização de Recursos Humanos , Inquéritos e Questionários , Adulto Jovem
16.
Neurosci Bull ; 29(4): 484-92, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23852559

RESUMO

Secondary damage is a critical determinant of the functional outcome in patients with spinal cord injury (SCI), and involves multiple mechanisms of which the most important is the loss of nerve cells mediated by multiple factors. Autophagy can result in cell death, and plays a key role in the development of SCI. It has been recognized that valproic acid (VPA) is neuroprotective in certain experimental animal models, however, the levels of autophagic changes in the process of neuroprotection by VPA treatment following SCI are still unknown. In the present study, we determined the extent of autophagy after VPA treatment in a rat model of SCI. We found that both the mRNA and protein levels of Beclin-1 and LC3 were significantly increased at 1, 2, and 6 h after SCI and peaked at 2 h; however, Western blot showed that autophagy was markedly decreased by VPA treatment at 2 h post-injury. Besides, post-SCI treatment with VPA improved the Basso-Beattie-Bresnahan scale, increased the number of ventral horn motoneurons, and reduced myelin sheath damage compared with vehicle-treated animals at 42 days after SCI. Together, our results demonstrated the characteristics of autophagy expression following SCI, and found that VPA reduced autophagy and enhanced motor function.


Assuntos
Autofagia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/patologia , Ácido Valproico/farmacologia , Animais , Proteínas Reguladoras de Apoptose/biossíntese , Proteína Beclina-1 , Western Blotting , Modelos Animais de Doenças , Feminino , Imunofluorescência , Proteínas Associadas aos Microtúbulos/biossíntese , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Yao Xue Xue Bao ; 48(11): 1705-9, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24475709

RESUMO

To screen the harmful substance 5-hydroxymethyl furfural content in commercially available traditional Chinese medicine injection which are commonly used, and to preliminarily evaluate the quality of these injections, 5-hydroxymethyl furfural was taken as an index. The contents of 5-hydroxymethyl furfural in 56 samples which consist of 23 kinds of traditional Chinese medicine injections and glucose injection were determined using LC-MS/MS, and 5-hydroxymethyl furfural was detected in 52 of these samples. The minimal content was 0.0038 microg x L(-1) and the maximum content was 1420 microg x mL(-1). The contents of 5-hydroxymethyl furfural were significantly different in traditional Chinese medicine injection which came from different kinds, manufacturers or batches. The results showed the quality difference of commercially available traditional Chinese medicine injection is significant taking 5-hydroxymethyl furfural content as assessment index. More attention should be paid to the safety of 5-hydroxymethyl furfural in traditional Chinese medicine injection, and unified limitation standard should be set to improve medication safety of traditional Chinese medicine injection.


Assuntos
Medicamentos de Ervas Chinesas/química , Furaldeído/análogos & derivados , Plantas Medicinais/química , Cromatografia Líquida , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Eleutherococcus/química , Furaldeído/análise , Glucose/administração & dosagem , Glucose/química , Injeções , Medicina Tradicional Chinesa , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Espectrometria de Massas em Tandem
18.
Chin Med ; 7(1): 21, 2012 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-23021236

RESUMO

BACKGROUND: Cichorium glandulosum Boiss. et Huet is used for treatment of liver disorders, and its effects are attributed to sesquiterpenes. This study aims to investigate the hepatoprotective effects of a sesquiterpene-rich fraction (SRF) from the aerial part of C. glandulosum on carbon tetrachloride (CCl4)-induced acute hepatotoxicity in mice, and on priming with Bacillus Calmette-Guerin (BCG) followed by lipopolysaccharide (LPS)-induced immunological liver injury in mice. METHODS: SRF was suspended in water and administered to mice at 0.05, 0.10 and 0.20 g/kg body weight for 7 consecutive days. An active control drug (bifendate pills) was suspended in distilled water and administered to mice at 0.40 g/kg body weight for 7 consecutive days. Hepatotoxicity was induced by intraperitoneal injection of 0.1% CCl4 (0.2 mL/mouse) at 13 h before the last drug administration, or by tail intravenous injection of BCG (0.2 mL/mouse) before the first drug administration and LPS (0.2 mL/mouse; 8 µg) at 15 h before the last drug administration. Blood samples and the livers were collected for evaluation of the biochemical parameters of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (TBIL). RESULTS: SRF significantly reduced the impact of CCl4 toxicity. The highest dose of SRF (0.20 g/kg) was the most effective, reflected by significant reductions in the levels of AST (P = 0.001), ALT (P = 0.000) and TBIL (P = 0.009). The serum enzymatic levels induced by BCG and subsequent LPS injection were significantly and dose-dependently restored by SRF, reflected by significant reductions in the levels of AST (P = 0.003), ALT (P = 0.003) and TBIL (P = 0.007) for the highest dose of SRF (0.20 g/kg). CONCLUSION: SRF is hepatoprotective in animal models of chemical and immunological acute liver injury.

19.
Appl Microbiol Biotechnol ; 94(6): 1521-32, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22391969

RESUMO

Violacein (Vio) is an important purple pigment with many potential bioactivities. Deoxyviolacein, a structural analog of Vio, is always synthesized in low concentrations with Vio in wild-type bacteria. Due to deoxyviolacein's low production and difficulties in isolation and purification, little has been learned regarding its function and potential applications. This study was the first effort in developing a stable and efficient biosynthetic system for producing pure deoxyviolacein. A recombinant plasmid with vioabce genes was constructed by splicing using an overlapping extension-polymerase chain reaction, based on the Vio-synthesizing gene cluster of vioabcde, originating from Duganella sp. B2, and was introduced into Citrobacter freundii. With the viod gene disrupted in the Vio synthetic pathway, Vio production was completely abolished and the recombinant C. freundii synthesized only deoxyviolacein. Interestingly, vioe gene expression was strongly stimulated in the viod-deleted recombinant strain, indicating that viod disruptions could potentially induce polar effects upon the downstream vioe gene within this small operon. Deoxyviolacein production by this strain reached 1.9 g/L in shaker flasks. The product exhibited significant acid/alkali and UV resistance as well as significant inhibition of hepatocellular carcinoma cell proliferation at low concentrations of 0.1-1 µM. These physical characteristics and antitumor activities of deoxyviolacein contribute to illuminating its potential applications.


Assuntos
Vias Biossintéticas , Citrobacter freundii/metabolismo , Indóis/metabolismo , Pigmentos Biológicos/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citrobacter freundii/genética , Humanos , Indóis/química , Indóis/farmacologia , Estrutura Molecular , Família Multigênica , Pigmentos Biológicos/química , Pigmentos Biológicos/farmacologia
20.
World J Gastroenterol ; 17(32): 3745-51, 2011 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21990957

RESUMO

AIM: To investigate the expression of Toll-like receptor (TLR) 3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma (ESCC). METHODS: Reverse transcription-polymerase chain reaction and immunohistochemistry were used to analyze the expression of TLR3, TLR4, TLR7 and TLR9 mRNA and protein in samples from 87 esophageal cancer patients consisting of both tumor and normal tissue. RESULTS: A significant increase in TLR3, TLR4, TLR7 and TLR9 mRNA levels was detected in ESCC samples. Tumors exhibited high TLR protein expression, (70.1%, 72.4%, 66.7% and 78.2% for TLR3, TLR4, TLR7 and TLR9, respectively, P < 0.05). Nevertheless, a significant percentage of tumors also exhibited TLR4 expression in mononuclear inflammatory cells (48.3%) and TLR9 expression in fibroblast-like cells (60.9%). Tumors with high TLR3 expression in tumor cells or high TLR4 expression in mononuclear inflammatory cells were significantly associated with a higher probability of lymph node metastasis and increased depth of invasion. However, tumors with high TLR9 expression in fibroblast-like cells were associated with low probabilities of invasion and metastasis. There was no significant variation between the expression of TLR3, TLR4, TLR7 and TLR9 among different ethnic groups. CONCLUSION: TLR3, TLR4, TLR7 and TLR9 expression appears important to the biological pathogenesis of ESCC. TLRs may represent therapeutic targets for ESCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor 7 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor 3 Toll-Like/genética , Receptor 4 Toll-Like/genética , Receptor 7 Toll-Like/genética , Receptor Toll-Like 9/genética
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