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This study systematically combed the randomized controlled trial(RCT) of Chinese patent medicines in treatment of type 2 diabetes mellitus(T2DM) in recent five years by using the method of evidence map. It understood the distribution and quality of evidence in this field and found the existing Chinese patent medicines in treatment of T2DM and the problems in its research. The study collected the commonly used Chinese patent medicines for the treatment of T2DM from three drug catalogs, retrieved Chinese and English databases to obtain RCT literature related to Chinese patent medicines in recent five years, and extracted information such as sample size, study drug, combination medication, course of treatment, and outcome indicators from the literature. It also conducted quality evaluation based on the Cochrane collaborative network bias risk assessment tool and used charts to display the analysis results. A total of 19 kinds of Chinese patent medicines are collected, of which 13 kinds of Chinese patent medicines are mentioned in 131 articles related to RCT. The literature concerning Shenqi Jiangtang Capsules/Granules, Jinlida Granules, and Xiaoke Pills accounts for a large proportion. Outcome indicators include blood glucose, blood lipids, pancreatic islet cell function, and clinical symptoms. In terms of literature quality, 75 articles have correct random methods, and 1 article performs allocation hiding and blind methods. Therefore, the clinical orientation of Chinese patent medicines for the treatment of T2DM is broad, failing to reflect their own characteristics and lacking safety information. Insufficient attention has been paid to TCM syndrome scores, quality of life, and blood lipid outcome indicators that reflect the characteristics of traditional Chinese medicine(TCM). The number of studies on the treatment of T2DM by Chinese patent medicines varies greatly among varieties, and the quality of the studies is low. It is suggested that the holders of the marketing license of T2DM Chinese patent medicines should carry out a post-marketing re-evaluation of the varieties of traditional Chinese patent medicines for treating T2DM according to the relevant requirements of the State Food and Drug Administration, standardize the clinical positioning, and revise and improve the safety information in the instructions. It is recommended that researchers construct a core indicator dataset for Chinese patent medicine treatment of T2DM, improve the efficacy evaluation system, and develop an experimental plan based on CONSORT before conducting RCT.
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Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/efeitos adversos , Medicina Tradicional Chinesa , Medicamentos sem Prescrição/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
By combining molecule dynamics (MD) simulation and quantum chemistry computation, we calculate the surface sum-frequency vibrational spectroscopy (SFVS) of R-limonene molecules at the gas-liquid interface for SSP, PPP, and SPS polarization combinations. The distributions of the Euler angles are obtained using MD simulation, the ψ-distribution is between isotropic and Gaussian. Instead of the MD distributions, different analytical distributions such as the δ-function, Gaussian and isotropic distributions are applied to simulate surface SFVS. We find that different distributions significantly affect the absolute SFVS intensity and also influence on relative SFVS intensity, and the δ-function distribution should be used with caution when the orientation distribution is broad. Furthermore, the reason that the SPS signal is weak in reflected arrangement is discussed.
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Cicloexenos/química , Simulação de Dinâmica Molecular , Análise Espectral , Terpenos/química , Algoritmos , Gases/química , Limoneno , Propriedades de Superfície , VibraçãoRESUMO
The novel HLA-C*15:279 allele differs from HLA-C*15:02:01:01 by five nucleotide substitutions in exons 4 and 5.
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Alelos , Povo Asiático , Sequência de Bases , Éxons , Antígenos HLA-C , Teste de Histocompatibilidade , Análise de Sequência de DNA , Humanos , Antígenos HLA-C/genética , Povo Asiático/genética , Análise de Sequência de DNA/métodos , Teste de Histocompatibilidade/métodos , Alinhamento de Sequência , Códon , População do Leste AsiáticoRESUMO
With the rapid development of the livestock industry, finding new sources of feed has become a critical issue that needs to be addressed urgently. China is one of the top five sunflower producers in the world and generates a massive amount of sunflower stalks annually, yet this resource has not been effectively utilized. Therefore, in order to tap into the potential of sunflower stalks for animal feed, it is essential to explore and develop efficient methods for their utilization.In this study, various proportions of alfalfa and sunflower straw were co-ensiled with the following mixing ratios: 0:10, 2:8, 4:6, 5:5, 6:4, and 8:2, denoted as A0S10, A2S8, A4S6, A5S5, A6S4, and A8S2, respectively. The nutrient composition, fermentation quality, microbial quantity, microbial diversity, and broad-spectrum metabolomics on the 60th day were assessed. The results showed that the treatment groups with more sunflower straw added (A2S8, A4S6) could start fermentation earlier. On the first day of fermentation, Weissella spp.dominated overwhelmingly in these two groups. At the same time, in the early stage of fermentation, the pH in these two groups dropped rapidly, which could effectively reduce the loss of nutrients in the early stage of fermentation.In the later fermentation period, a declining trend in acetic acid levels was observed in A0S10, A2S8, and A4S6, while no butyric acid production was detected in A0S10 and A2S8 throughout the process. In A4S6, butyric acid production was observed only after 30 days of fermentation. From the perspective of metabolites, compared with sunflower ensiling alone, many bioactive substances such as flavonoids, alkaloids, and terpenes are upregulated in mixed ensiling.
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Caveolin-1 is one of the major constituents of caveolae. Both Cav-1 and PrP are plasma membrane proteins, which show active capacities for molecular interactions with many other proteins or agents, including themselves. Using yeast two-hybrid system and immunoprecipitation, we reconfirmed the molecular interaction between human Cav-1 and PrP. With co-immunoprecipitation tests, PrP(C)-Cav-1 and PrP(Sc)-Cav-1 complexes were identified in the brain homogenates of normal and scrapie agent 263K-infected hamsters, respectively. Transient expression of wild-type PrP (PrP-PG5) in HEK293 cells did not change the situation of Cav-1 and subsequent signal transduction pathways, while cross-linking of the expressed PrP with specific antibody induced remarkable colocalization of PrP and Cav-1 on the plasma membrane and significant increases of phosphorylated Cav-1 and phosphorylated Fyn. With deleted and inserted PrP mutants within octarepeat region, we observed obvious octarepeat-associated phenomena, including lower binding capacity with Cav-1 in vitro, unable to co-localize with Cav-1 in the cells and to induce up-regulation of p-Cav-1 and p-Fyn when removal of octarepeats in the context of full-length PrP. Moreover, we found that treatment on HEK293 cells with fibrous form of recombinant PrP protein led to up-regulating the levels of p-Cav-1 and p-Fyn. Our data here provide strong evidence that octarepeats of PrP are critical for the interaction between PrP and Cav-1. Significant alterations in the cultured cells, either the distributions of PrP and Cav-1 morphologically or the up-regulations of p-Cav-1 and p-Fyn, induced by antibody-mediated cross-linking or fibrous forms of PrP may suggest a possible internalization process of PrP(Sc).
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Caveolina 1/metabolismo , Príons/metabolismo , Sequências Repetitivas de Aminoácidos , Animais , Encéfalo/patologia , Linhagem Celular , Cricetinae , Análise Mutacional de DNA , Humanos , Imunoprecipitação , Mesocricetus , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fosforilação , Príons/genética , Ligação Proteica , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Técnicas do Sistema de Duplo-HíbridoRESUMO
OBJECTIVE: To investigate the effect of elemene on reversing chemoresistance to adriamycin (ADM) in human stomach cancer cell, and explore its possible mechanism. METHODS: SGC7901/ADM were divided imto two groups: control group and elemene treatment group. The cytotoxicity of ADM on SGC7901/ADM was determined by MTT assay. The activity of nuclear factor-kappa B (NF-kappaB) was measured by immunohistochemical staining. The apoptosis rate of stomach cancer cell line was determined by flow cyotometric analysis. RESULTS: The immunohistochemical staining result showed that the activity of NF-kappaB in SGC7901/ADM was increased after treated with ADM for 9 - 12 h, while that of the elemene treatment group decreased with the increasing of the elemene concentration and the lowest level was 8 - 12%. The apoptosis rate of SGC7901/ADM stomach cancer cell line was increased with the increasing of elemene concentration. At the same elemene concentration, the apoptosis rate increased with ADM treatment time prolonged. MTT result showed that the non-cytotoxic dose of elemene had synergistic effect on rilling SGC7901/ADM stomach cancer cell line and was in a dose-dependant manner. CONCLUSION: The inhibitory effect of elemene on reversing chemoresistance to ADM in human stomach cancer cell line maybe related to inhibiting NF-kappaB activity.
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Antineoplásicos Fitogênicos/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Neoplasias Gástricas/patologia , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Curcuma/química , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Citometria de Fluxo , Humanos , Imuno-Histoquímica , NF-kappa B/metabolismo , Sesquiterpenos/administração & dosagem , Neoplasias Gástricas/metabolismoRESUMO
BACKGROUND: Soybean (Glycine max L.) is one of the most important oil crops in the world. It is desirable to increase oil yields from soybean, and so this has been a major goal of oilseed engineering. However, it is still uncertain how many genes and which genes are involved in lipid biosynthesis. RESULTS: Here, we evaluated changes in gene expression over the course of seed development using Illumina (formerly Solexa) RNA-sequencing. Tissues at 15 days after flowering (DAF) served as the control, and a total of 11592, 16594, and 16255 differentially expressed unigenes were identified at 35, 55, and 65 DAF, respectively. Gene Ontology analyses detected 113 co-expressed unigenes associated with lipid biosynthesis. Of these, 15 showed significant changes in expression levels (log2fold values ≥ 1) during seed development. Pathway analysis revealed 24 co-expressed transcripts involved in lipid biosynthesis and fatty acid biosynthesis pathways. We selected 12 differentially expressed genes and analyzed their expressions using qRT-PCR. The results were consistent with those obtained from Solexa sequencing. CONCLUSION: These results provide a comprehensive molecular biology background for research on soybean seed development, particularly with respect to the process of oil accumulation. All of the genes identified in our research have significance for breeding soybeans with increased oil contents.
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Mineração de Dados , Perfilação da Expressão Gênica , Glycine max/metabolismo , Lipídeos/biossíntese , Sementes/crescimento & desenvolvimento , Análise de Sequência de RNA , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Metabolismo dos Lipídeos , Lipídeos/genética , Anotação de Sequência Molecular , RNA de Plantas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/metabolismo , Óleo de Soja/genética , Óleo de Soja/metabolismo , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Fatores de TempoRESUMO
OBJECTIVE: To investigate the effects of intrathecal injection of ginsenoside Rg1 at different doses on the changes of the behavior and the expressions of excitatory amino-acid transporter 1 (EAAT1), i. e., glutamate-aspartate transporter (GLAST) in the spinal dorsal horn of the arthritis rats with chronic morphine tolerance, and further to explore its mechanisms for morphine tolerance. METHODS: After successful intrathecal injection, an adjuvant arthritis model was established in 36 healthy male SD rats. They were randomly divided into 6 groups, 6 in each group. They were intrathecally injected with 10 microL normal saline (Group NS), 10 microg morphine (Group M), 10 microg morphine + 50 microg ginsenoside Rg1 (Group MG50), 10 microg morphine +100 microg ginsenoside Rg1 (Group MG100), 10 microg morphine + 200 microg ginsenoside Rg1 (Group MG200), and 100 microg ginsenoside Rg1 (Group G100), respectively. The normal saline and morphine were intrathecally injected twice daily, while ginsenoside Rg1 at different doses was intrathecally injected once daily, for 7 successive days. Fifty percent mechanical paw withdrawal threshold (PWT) was dynamically detected to evaluate their behaviors. The rats were sacrificed on day 7 after medication. The L3-L5 segment of the spinal cord was isolated for determining the expression of GLAST in the spinal dorsal horn using immunofluorescence staining. RESULTS: The PWT of Group M was significantly higher than that of Group NS on the 1st and 3rd day after medication (P < 0.05). But it was gradually shortened along with the increasing days of medication. There was no statistical difference between Group M and Group NS on the 7th day (P > 0.05), indicating the formation of morphine tolerance. The PWT of Group MG100 also showed a decreasing tendency, but obviously slower than that of Group M (P < 0.05). The PWT of Group G100 was higher than that of Group NS (P < 0.05). Compared with Group NS, the expression of GLAST in the spinal dorsal horn of rats in Group M was down-regulated (P < 0.01). Compared with Group M, the expression of GLAST in the spinal dorsal horn of rats in Group MG100 and Group G100 was up-regulated (P < 0.05). CONCLUSIONS: Single application of ginsenoside Rg1 showed mild antinociceptive effect in adjuvant-induced arthritis rats. Intrathecal injection of 100 microg ginsenoside Rg1 could attenuate the formation of morphine tolerance. Its mechanisms might be correlated with up-regulating of the expression of GLAST.
Assuntos
Sistema X-AG de Transporte de Aminoácidos/metabolismo , Artrite Experimental/metabolismo , Tolerância a Medicamentos , Ginsenosídeos/farmacologia , Animais , Ginsenosídeos/administração & dosagem , Injeções Espinhais , Masculino , Morfina/farmacologia , Medição da Dor , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To create transgenic mice expressing hamster- and human-PRNP as a model for understanding the physiological function and pathology of prion protein (PrP), as well as the mechanism of cross-species transmission of transmissible spongiform encephalopathies (TSEs). METHODS: Hamster and human-PRNP transgenic mice were established by conventional methods. The copy number of integrated PRNP in various mouse lines was mapped by real-time PCR. PRNP mRNA and protein levels were determined by semi-quantitative RT-PCR, real-time RT-PCR, and western blot analysis. Histological analyses of transgenic mice were performed by hematoxylin and eosin (H & E) staining and immunohistochemical (IHC) methods. RESULTS: Integrated PRNP copy number in various mouse lines was 53 (Tg-haPrP1), 18 (Tg-huPrP1), 3 (Tg-huPrP2), and 16 (Tg-huPrP5), respectively. Exogenous PrPs were expressed at both the transcriptional and translational level. Histological assays did not detect any abnormalities in brain or other organs. CONCLUSION: We have established one hamster-PRNP transgenic mouse line and three human-PRNP transgenic mouse lines. These four transgenic mouse lines provide ideal models for additional research.
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Camundongos Transgênicos , Príons/genética , Animais , Western Blotting , Cricetinae , DNA/genética , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Plasmídeos , Doenças Priônicas/genética , Proteínas Priônicas , Reação em Cadeia da Polimerase em Tempo Real , Transcrição GênicaRESUMO
Migraine is one of the most common and highest burdens of disease. As a primary cerebral dysfunction illness, migraine might exhibit other system-related symptoms, including vestibular and cochlear symptoms. With the publication of the diagnostic criteria of vestibular migraine, the link between migraine and vestibular symptoms became clear. However, the relationship between migraine and cochlear symptoms is far from straightforward. Therefore, we focus on the correlation between migraine and deafness, sudden sensorineural hearing loss, acute tinnitus, and chronic tinnitus to better understand the relationship between migraine and cochlear symptoms.
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Doenças Cocleares/epidemiologia , Perda Auditiva Súbita/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Vertigem/epidemiologia , Cóclea/patologia , Doenças Cocleares/complicações , Doenças Cocleares/patologia , Perda Auditiva Súbita/complicações , Perda Auditiva Súbita/patologia , Humanos , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/patologia , Zumbido/epidemiologia , Zumbido/patologia , Sistema Vestibular/patologiaRESUMO
Nerve growth factor (NGF), a member of the neurotrophin family, is essential for the development and maintenance of sensory neurons and for the formation of central pain circuitry. The current study was designed to evaluate the expression of NGF in the brain of rats with spared nerve injury (SNI), using immunohistochemical technique. The results showed that the level of NGF in the Red nucleus (RN) of SNI rats was apparently higher than that of sham-operated rats. To further study the effect of NGF in the development of neuropathic pain, different doses of anti-NGF antibody (20, 2.0 and 0.2 microg/ml) were microinjected into the RN contralateral to the nerve injury side of SNI rats. The data suggested that the higher doses of anti-NGF antibody (20 and 2.0 microg/ml) significantly attenuated the mechanical allodynia of neuropathic rats, while the 0.2 microg/ml antibody showed no analgesic effect. These results suggest that the NGF of RN is involved in the development of neuropathic allodynia in SNI rats.
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Fator de Crescimento Neural/biossíntese , Dor/tratamento farmacológico , Núcleo Rubro/metabolismo , Neuropatia Ciática/fisiopatologia , Animais , Fator de Crescimento Neural/imunologia , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSNHL) is a common form of deafness. Acupuncture has been used as a salvage therapy for ISSNHL in China since 200 BCE. However, the efficacy of acupuncture has not been confirmed in strictly controlled trials. We designed a randomized controlled clinical trial to evaluate the efficacy and long-term effects of acupuncture in patients with early ISSNHL. METHODS/DESIGN: In this randomized controlled clinical trial, we will enroll 124 participants with ISSNHL diagnosed 2 to 4 weeks prior to enrollment, who have shown little hearing improvement after routine Western medical treatment (i.e., corticosteroids). 62 of these participants will have flat audiogram and the other 62 will have a high-frequency drop audiogram; they will all take Methycobal while half of the flat type and half of the high-frequency drop type will also receive acupuncture treatments for 4 weeks in a four-group design. The primary outcome measure will be the effective rate of hearing improvement (defined as the proportion of patients with at least 15-dB improvement in the hearing loss frequency band). The secondary outcome will measure the improvements in Pure Tone Average, Word Recognition Score, and Tinnitus Handicap Inventory. The assessments of the participants will be made at baseline, after treatment (week 4), and at follow-up (week 28). DISCUSSION: This study aims to explore the efficacy and long-term effects of acupuncture in patients with ISSNHL. This study will be a randomized controlled trial with strict methodology and few design deficits. If our study yields positive results, acupuncture could be recommended as a salvage therapy for patients with ISSNHL. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR-ICR-15006787 . Registered on 12 July 2015.
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Terapia por Acupuntura/métodos , Perda Auditiva Neurossensorial/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto , Idoso , Audiometria , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Controle de Qualidade , Projetos de PesquisaRESUMO
OBJECTIVE: To investigate the fundamental pathological anatomy and possible pathogenetic factors of Ménière's disease(MD), we compared the types of mastoid air cells between the MD group and the control group. METHODS: The MD group had 113 ears and the control group had 100 ears. Temoral bone CT scanning was performed in all the subjects. The types of mastoid air cells were determined by surgical findings and imaging data. All the mastoid air cells were divided into diploetic type, gasified type and sclerosis type. Analysis of the proportion of different types and the statistical analysis were performed between the two groups. RESULTS: 51.4% (57/113) in the MD group and 18.0% (18/100) in the control group were diploetic type mastoid, the difference was significant (χ(2) = 24.476, P < 0.001). The gasified type was 43.4% (49/113) in the MD group and 77.0% (77/100) in the control group, the difference was significant (χ(2) = 24.843, P < 0.001). The sclerosis type was 6.2% in the MD group and 5.0% (5/100) in the control group, and there was no statistical significance (χ(2) = 0.142,P > 0.05). CONCLUSIONS: The mastoid air cells are dysplasia in MD patients, and it may be one of the fundamental pathological anatomy. The long-term ventilation and drainage disorder and recurrent inflammation attack may play an important role in occurrence, development and prognosis of MD.
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Saco Endolinfático/patologia , Processo Mastoide/patologia , Doença de Meniere/patologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Organic photonic heterostructures are constructed through a template-free self-assembly method. The host-guest intermolecular interactions play an essential role in the formation of various block orange-blue-orange and blue/green microtubes. The spatial distribution of excitons is engineered to investigate the excitonic behaviors in light propagation along the axial heterostructures. These results offer a new route to the integration of organic photonic building blocks for optical processing applications.
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Transferência Ressonante de Energia de Fluorescência , Luz , Nanoestruturas/química , Compostos Organometálicos/química , Transferência Ressonante de Energia de Fluorescência/métodos , Óptica e Fotônica/métodos , FótonsRESUMO
Development of the pathogenesis of transmissible spongiform encephalopathies (TSEs) requires the presence of both the normal host prion protein (PrPC) and the abnormal pathological proteinase-K resistant isoform (PrPSc). Reduction of PrPC levels has been shown to extend survival time after prion infection. In this report, based on analysis of the known sequences of human PrP, we constructed two small interfering RNA (siRNA) duplexes targeting the segments of amino acids (aa) 108-114 (Ri2) and aa 171-177 (Ri3). Western blot analysis results revealed that these PrP-specific siRNAs could effectively knock down the levels of either endogenous PrP in human neuroblastoma SHSY-5Y cells or recombinant PrP transfected with the plasmid expressing the full-length human PrP in human embryonic kidney (HEK) 293T cells. Meanwhile, the two siRNAs also showed a significant effect on the reduction of the expression of the PrP-PG9 and PrP-PG12 familial Creutzfeldt-Jakob disease (CJD)-associated PrP mutants with four and seven extra octarepeats, in the cells transfected with the respective expression plasmids. MTT tests identified that knockdown of wild-type PrP by Ri2 and Ri3 did not change the cell growth capacities, but significantly decreased the cell resistances against the challenge of Cu2+. Co-expression of Ri2 and Ri3 partially antagonized the cytotoxicity caused by expressing PrP-PG9 and PrP-PG12 in the two cell lines. Moreover, the rescuing effectiveness of PrP siRNAs was time-related, with the more efficient antagonism of the cytotoxicity of fCJD-associated PrP mutants occurring at the early stages after transfection. The data shown here provide useful clues for seeking potential therapeutic tools for prion diseases.
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Cobre/toxicidade , Íons/metabolismo , Príons/genética , Interferência de RNA , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Sobrevivência Celular , Síndrome de Creutzfeldt-Jakob/genética , Endopeptidase K/genética , Endopeptidase K/metabolismo , Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Neuroblastoma/metabolismo , Plasmídeos , Proteínas PrPC/química , Proteínas PrPC/genética , Proteínas PrPC/metabolismo , Príons/metabolismo , RNA Interferente Pequeno/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNARESUMO
Amyloid-like fibrils have been associated with the pathogenesis of human prion diseases. Prion peptide of aa 106-126 (PrP106-126) exhibits many PrP(Sc)-like biochemical features, forming amyloid-like fibrils in vitro. Here, we found that the recombinant yeast-derived molecular chaperon Hsp104 inhibited significantly the fibril assembly of the synthetic PrP106-126 peptide by dynamic ThT assays in vitro. EM assays revealed almost no fibril-like structure after incubation of the synthetic PrP106-126 peptides with Hsp104 for 12h. Circular dichroism assays identified that treatment of Hsp104 shifted the secondary structure of PrP106-126 fibrils from ß-sheet to a random coil. MTT tests confirmed that interaction of PrP106-126 with Hsp104 maintained the toxicity of PrP106-126 on human neuroblastoma cell line SK-N-SH. Additionally, Hsp104 was able to disassemble the mature PrP106-126 fibrils in vitro, leading to recovering the cytotoxicity of PrP106-126 on SK-N-SH cells. Our study provides the molecular evidences that the yeast-derived Hsp104 can interfere in the fibril assembly and disassembly of human PrP106-126 segment.
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Proteínas Fúngicas/farmacologia , Proteínas de Choque Térmico/farmacologia , Fragmentos de Peptídeos/química , Príons/química , Multimerização Proteica/efeitos dos fármacos , Sequência de Aminoácidos , Linhagem Celular Tumoral , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/toxicidade , Príons/toxicidade , Estrutura Secundária de Proteína/efeitos dos fármacos , Desdobramento de Proteína/efeitos dos fármacosRESUMO
Prion protein (PrP) is a ubiquitous conserved glycoprotein predominantly expressed in neurons of the central nervous system (CNS). To elucidate on its cellular function, we performed a yeast two-hybrid screen within an adult human brain cDNA library for potential PrP-binding molecules. A novel protein, HS-1 associated protein X-1 (HAX-1), was identified to be able to bind with PrP strongly. The interaction between the two proteins has been further verified by glutathione-S-transferase (GST) pull-down and immunoprecipitation assays. The minimal binding regions were mapped to the segments of residues aa 91-163 for PrP(C) and residues aa 38-129 for HAX-1. Immunofluorescent assays of co-expressions of human PrP and HAX-1 in 293T and SHSY-5Y cells revealed marked co-localizations of those two proteins in cytoplasm. Moreover, the co-expression of HAX-1 and wild-type PrP (PG5) was found to enhance the cellular resistance to the challenge of H2O2. Contrarily, co-transfection of HAX-1 did not reverse but aggravated the cytotoxicities of the genetic CJD (gCJD) associated PrP mutants with nine- (PG9) and fourteen-octarepeats (PG14). Our data provide for the first time a new PrP-interacting partner that may play role in cell oxidative stress and anti-apoptosis physiologically and cell damage pathologically.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Cultivadas/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Príons/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Células HEK293/efeitos dos fármacos , Humanos , Estresse Oxidativo , Doenças Priônicas/patologia , Doenças Priônicas/fisiopatologia , Príons/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Técnicas do Sistema de Duplo-HíbridoRESUMO
Prion protein (PrP) is able to bind with tubulin and to interfere with the formation of microtubule. To investigate the influence of accumulation of cytosolic PrP in cytoplasm on microtubule, plasmid pcDNA3.1-PrP23-230 expressing human PrP23-230 was introduced into HeLa cells. Immunoprecipitation assays identified the molecular interaction between cytosolic PrP and cellular tubulin. Confocal microscopy showed the co-localization of the expressed cytosolic PrP with tubulin in cytoplasm. Immunofluorescent assays of tubulin illustrated remarkable disruption of microtubular structures in the cells accumulated with cytosolic PrP. Meanwhile, the expressed cytosolic PrP significantly reduced cell viability and induced cell apoptosis. The amounts of microtubule protein in the cells expressing cytosolic PrP were decreased. Moreover, the levels of endogenous tubulin in the brain tissues of scrapie-infected hamsters were significantly lower than that of normal one. It highlights a close linkage between disruption of microtubule framework and cell death caused by abnormal presence of cellular PrP in cytoplasm. The association of apoptosis with microtubule-disrupting activity caused by cytosolic PrP may further provide insight into the unresolved biological function of PrP in the neurons.
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Apoptose/fisiologia , Citosol/metabolismo , Microtúbulos/metabolismo , Príons/metabolismo , Animais , Cricetinae , Células HeLa , Humanos , Mesocricetus , Príons/genética , Scrapie/metabolismo , Scrapie/patologiaRESUMO
BACKGROUND: Tubulin polymerization promoting protein/p25 (TPPP/p25), known as a microtubule-associated protein (MAP), is a brain-specific unstructured protein with a physiological function of stabilizing cellular microtubular ultrastructures. Whether TPPP involves in the normal functions of PrP or the pathogenesis of prion disease remains unknown. Here, we proposed the data that TPPP formed molecular complex with PrP. We also investigated its influence on the aggregation of PrP and fibrillization of PrP106-126 in vitro, its antagonization against the disruption of microtubule structures and cytotoxicity of cytosolic PrP in cells, and its alternation in the brains of scrapie-infected experimental hamsters. METHODOLOGY/PRINCIPAL FINDINGS: Using pull-down and immunoprecipitation assays, distinct molecular interaction between TPPP and PrP were identified and the segment of TPPP spanning residues 100-219 and the segment of PrP spanning residues 106-126 were mapped as the regions responsible for protein interaction. Sedimentation experiments found that TPPP increased the aggregation of full-length recombinant PrP (PrP23-231) in vitro. Transmission electron microscopy and Thioflavin T (ThT) assays showed that TPPP enhanced fibril formation of synthetic peptide PrP106-126 in vitro. Expression of TPPP in the cultured cells did not obviously change the microtubule networks observed by a tubulin-specific immunofluorescent assay and cell growth features measured by CCK8 tests, but significantly antagonized the disruption of microtubule structures and rescued the cytotoxicity caused by the accumulation of cytosolic PrP (CytoPrP). Furthermore, Western blots identified that the levels of the endogenous TPPP in the brains of scrapie-infected experimental hamsters were significantly reduced. CONCLUSION/SIGNIFICANCE: Those data highlight TPPP may work as a protective factor for cells against the damage effects of the accumulation of abnormal forms of PrPs, besides its function as an agent for dynamic stabilization of microtubular ultrastructures.
Assuntos
Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Príons/metabolismo , Sequência de Aminoácidos , Amiloide/metabolismo , Amiloide/ultraestrutura , Animais , Benzotiazóis , Western Blotting , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Cricetinae , Citosol/metabolismo , Células HeLa , Humanos , Imunoprecipitação , Mesocricetus , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/genética , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Fragmentos de Peptídeos/metabolismo , Príons/genética , Ligação Proteica , Scrapie/metabolismo , Tiazóis/metabolismoRESUMO
OBJECTIVE: To analyze the nystagmus during particle repositioning maneuver for posterior semicircular canal benign paroxysmal positional vertigo (PC-BPPV), and verify different pathogenesis of benign paroxysmal positional vertigo (BPPV). METHODS: The chief complains, nystagmus during positioning test and particle repositioning maneuver (PRM) were recorded in detail from 66 PC-BPPV cases during Dec.2007 and Apr.2008, and verifying possible pathogenesis of BPPV was based on nystagmus. RESULTS: Of all 66 PC-BPPV cases, the four positions of PRM were found in 24 cases presented upward torsional nystagmus at the second or third position, 21 cases presented negative nystagmus except the first position, 7 cases presented intensity horizontal nystagmus during PRM and 14 cases presented downward nystagmus at the second or third position during PRM. Of all 66 cases, 78.8% of them were accord with canalithiasis and cupulolithiasis while the other may be related with otolith organ or nerve disease. CONCLUSIONS: Besides canalithiasis and cupulolithiasis, part of BPPV may be related with otolith organ or nerve disease.