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1.
J Chem Inf Model ; 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35533292

RESUMO

Global optimization of multicomponent cluster structures is considerably time-consuming due to the existence of a vast number of isomers. In this work, we proposed an improved self-adaptive differential evolution with the neighborhood search (SaNSDE) algorithm and applied it to the global optimization of bimetallic cluster structures. The cross operation was optimized, and an improved basin hopping module was introduced to enhance the searching efficiency of SaNSDE optimization. Taking (PtNi)N (N = 38 or 55) bimetallic clusters as examples, their structures were predicted by using this algorithm. The traditional SaNSDE algorithm was carried out for comparison with the improved SaNSDE algorithm. For all the optimized clusters, the excess energy and the second difference of the energy were calculated to examine their relative stabilities. Meanwhile, the bond order parameters were adopted to quantitatively characterize the cluster structures. The results reveal that the improved SaNSDE algorithm possessed significantly higher searching capability and faster convergence speed than the traditional SaNSDE algorithm. Furthermore, the lowest-energy configurations of (PtNi)38 clusters could be classified as the truncated octahedral and disordered structures. In contrast, all the optimal (PtNi)55 clusters were approximately icosahedral. Our work fully demonstrates the high efficiency of the improved algorithm and advances the development of global optimization algorithms and the structural prediction of multicomponent clusters.

2.
Front Psychol ; 12: 759229, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744935

RESUMO

Objective: This study aims to implement and investigate the application of a special intelligent diagnostic system based on deep learning in the diagnosis of pterygium using anterior segment photographs. Methods: A total of 1,220 anterior segment photographs of normal eyes and pterygium patients were collected for training (using 750 images) and testing (using 470 images) to develop an intelligent pterygium diagnostic model. The images were classified into three categories by the experts and the intelligent pterygium diagnosis system: (i) the normal group, (ii) the observation group of pterygium, and (iii) the operation group of pterygium. The intelligent diagnostic results were compared with those of the expert diagnosis. Indicators including accuracy, sensitivity, specificity, kappa value, the area under the receiver operating characteristic curve (AUC), as well as 95% confidence interval (CI) and F1-score were evaluated. Results: The accuracy rate of the intelligent diagnosis system on the 470 testing photographs was 94.68%; the diagnostic consistency was high; the kappa values of the three groups were all above 85%. Additionally, the AUC values approached 100% in group 1 and 95% in the other two groups. The best results generated from the proposed system for sensitivity, specificity, and F1-scores were 100, 99.64, and 99.74% in group 1; 90.06, 97.32, and 92.49% in group 2; and 92.73, 95.56, and 89.47% in group 3, respectively. Conclusion: The intelligent pterygium diagnosis system based on deep learning can not only judge the presence of pterygium but also classify the severity of pterygium. This study is expected to provide a new screening tool for pterygium and benefit patients from areas lacking medical resources.

3.
J Clin Med ; 10(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34640509

RESUMO

High myopia is a global ocular disease and one of the most common causes of blindness. Fundus images can be obtained in a noninvasive manner and can be used to monitor and follow up on many fundus diseases, such as high myopia. In this paper, we proposed a computer-aided diagnosis algorithm using deep convolutional neural networks (DCNNs) to grade the risk of high myopia. The input images were automatically classified into three categories: normal fundus images were labeled class 0, low-risk high-myopia images were labeled class 1, and high-risk high-myopia images were labeled class 2. We conducted model training on 758 clinical fundus images collected locally, and the average accuracy reached 98.15% according to the results of fivefold cross-validation. An additional 100 fundus images were used to evaluate the performance of DCNNs, with ophthalmologists performing external validation. The experimental results showed that DCNNs outperformed human experts with an area under the curve (AUC) of 0.9968 for the recognition of low-risk high myopia and 0.9964 for the recognition of high-risk high myopia. In this study, we were able to accurately and automatically perform high myopia classification solely using fundus images. This has great practical significance in terms of improving early diagnosis, prevention, and treatment in clinical practice.

4.
BMC Health Serv Res ; 21(1): 1067, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627239

RESUMO

BACKGROUND: In the development of artificial intelligence in ophthalmology, the ophthalmic AI-related recognition issues are prominent, but there is a lack of research into people's familiarity with and their attitudes toward ophthalmic AI. This survey aims to assess medical workers' and other professional technicians' familiarity with, attitudes toward, and concerns about AI in ophthalmology. METHODS: This is a cross-sectional study design study. An electronic questionnaire was designed through the app Questionnaire Star, and was sent to respondents through WeChat, China's version of Facebook or WhatsApp. The participation was voluntary and anonymous. The questionnaire consisted of four parts, namely the respondents' background, their basic understanding of AI, their attitudes toward AI, and their concerns about AI. A total of 562 respondents were counted, with 562 valid questionnaires returned. The results of the questionnaires are displayed in an Excel 2003 form. RESULTS: There were 291 medical workers and 271 other professional technicians completed the questionnaire. About 1/3 of the respondents understood AI and ophthalmic AI. The percentages of people who understood ophthalmic AI among medical workers and other professional technicians were about 42.6 % and 15.6 %, respectively. About 66.0 % of the respondents thought that AI in ophthalmology would partly replace doctors, about 59.07 % having a relatively high acceptance level of ophthalmic AI. Meanwhile, among those with AI in ophthalmology application experiences (30.6 %), above 70 % of respondents held a full acceptance attitude toward AI in ophthalmology. The respondents expressed medical ethics concerns about AI in ophthalmology. And among the respondents who understood AI in ophthalmology, almost all the people said that there was a need to increase the study of medical ethics issues in the ophthalmic AI field. CONCLUSIONS: The survey results revealed that the medical workers had a higher understanding level of AI in ophthalmology than other professional technicians, making it necessary to popularize ophthalmic AI education among other professional technicians. Most of the respondents did not have any experience in ophthalmic AI but generally had a relatively high acceptance level of AI in ophthalmology, and there was a need to strengthen research into medical ethics issues.


Assuntos
Oftalmologia , Inteligência Artificial , Atitude do Pessoal de Saúde , Estudos Transversais , Humanos , Inquéritos e Questionários
5.
Transl Vis Sci Technol ; 10(7): 20, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34132760

RESUMO

Purpose: The discrepancy of the number between ophthalmologists and patients in China is large. Retinal vein occlusion (RVO), high myopia, glaucoma, and diabetic retinopathy (DR) are common fundus diseases. Therefore, in this study, a five-category intelligent auxiliary diagnosis model for common fundus diseases is proposed; the model's area of focus is marked. Methods: A total of 2000 fundus images were collected; 3 different 5-category intelligent auxiliary diagnosis models for common fundus diseases were trained via different transfer learning and image preprocessing techniques. A total of 1134 fundus images were used for testing. The clinical diagnostic results were compared with the diagnostic results. The main evaluation indicators included sensitivity, specificity, F1-score, area under the concentration-time curve (AUC), 95% confidence interval (CI), kappa, and accuracy. The interpretation methods were used to obtain the model's area of focus in the fundus image. Results: The accuracy rates of the 3 intelligent auxiliary diagnosis models on the 1134 fundus images were all above 90%, the kappa values were all above 88%, the diagnosis consistency was good, and the AUC approached 0.90. For the 4 common fundus diseases, the best results of sensitivity, specificity, and F1-scores of the 3 models were 88.27%, 97.12%, and 84.02%; 89.94%, 99.52%, and 93.90%; 95.24%, 96.43%, and 85.11%; and 88.24%, 98.21%, and 89.55%, respectively. Conclusions: This study designed a five-category intelligent auxiliary diagnosis model for common fundus diseases. It can be used to obtain the diagnostic category of fundus images and the model's area of focus. Translational Relevance: This study will help the primary doctors to provide effective services to all ophthalmologic patients.


Assuntos
Retinopatia Diabética , Glaucoma , Oftalmologistas , China , Retinopatia Diabética/diagnóstico , Fundo de Olho , Humanos
6.
BMC Gastroenterol ; 20(1): 401, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243141

RESUMO

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD), the pathogenesis of which is complicated, and it is difficult to treat. In recent years, the emerging fecal microbiota transplantation (FMT) has shown good effects in UC treatment and is therefore accepted by increasing numbers of patients. Our hospital has carried out FMT since 2017, and has achieved good results in UC treatment. We have found in our clinical work that the efficacy of re-FMT after recurrence decreased. This is difference from reported literatures. In order to attract clinical attention, here we selected typical cases for analysis. METHODS: Among all UC patients who received FMT in our hospital, 12 patients with moderate to severe UC were selected. They all received multiple FMT and were followed up for 52 weeks. Besides, none of them had other underlying diseases. Colonoscopy images of patients were presentated, SCCAI and UCDAI were used assess the effect of FMT. RESULTS: On the whole, FMT has a significant effect on moderate to severe UC. Of the 12 patients, 11 (91.7%) achieved a clinical response, 9 (75.0%) achieved clinical remission, and only one patient did not respond to FMT treatment. However, 6 patients relapsed within 52 weeks after remission, with a recurrence rate of 54.5%. Four of the six relapsed patients received FMT again, but the efficacy of FMT after relapse was significantly lower than that of the initial FMT. Fortunately, compared to before the initial FMT treatment, the severity of the disease after relapse was significantly reduced. CONCLUSION: FMT has a good effect on the relief of moderate to severe UC. However, the effect of FMT treatment after relapse is reduced. For patients who relapse after remission, the efficacy of FMT reapplication requires more experiments to verify.


Assuntos
Colite Ulcerativa , Transplante de Microbiota Fecal , Doenças Inflamatórias Intestinais , Adulto , Colite Ulcerativa/terapia , Fezes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Resultado do Tratamento
7.
Diabetes Ther ; 10(5): 1811-1822, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31290125

RESUMO

INTRODUCTION: In April 2018, the US Food and Drug Administration (FDA) approved the world's first artificial intelligence (AI) medical device for detecting diabetic retinopathy (DR), the IDx-DR. However, there is a lack of evaluation systems for DR intelligent diagnostic technology. METHODS: Five hundred color fundus photographs of diabetic patients were selected. DR severity varied from grade 0 to 4, with 100 photographs for each grade. Following that, these were diagnosed by both ophthalmologists and the intelligent technology, the results of which were compared by applying the evaluation system. The system includes primary, intermediate, and advanced evaluations, of which the intermediate evaluation incorporated two methods. Main evaluation indicators were sensitivity, specificity, and kappa value. RESULTS: The AI technology diagnosed 93 photographs with no DR, 107 with mild non-proliferative DR (NPDR), 107 with moderate NPDR, 108 with severe NPDR, and 85 with proliferative DR (PDR). The sensitivity, specificity, and kappa value of the AI diagnoses in the primary evaluation were 98.8%, 88.0%, and 0.89, respectively. According to method 1 of the intermediate evaluation, the sensitivity of AI diagnosis was 98.0%, specificity 97.0%, and the kappa value 0.95. In method 2 of the intermediate evaluation, the sensitivity of AI diagnosis was 95.5%, the specificity 99.3%, and kappa value 0.95. In the advanced evaluation, the kappa value of the intelligent diagnosis was 0.86. CONCLUSIONS: This article proposes an evaluation system for color fundus photograph-based intelligent diagnostic technology of DR and demonstrates an application of this system in a clinical setting. The results from this evaluation system serve as the basis for the selection of scenarios in which DR intelligent diagnostic technology can be applied.

8.
BMC Ophthalmol ; 19(1): 132, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226955

RESUMO

BACKGROUND: Although the pathogenesis of glaucoma is not fully understood,an elevated intraocular pressure (IOP) is a major factor contributing to its development and progression. The aim of this study was to investigate the changes in the vessel densities of the macula and optic nerve head (ONH) after an acute elevation in the intraocular pressure (IOP) observed using optical coherence tomography angiography (OCTA). METHODS: This was a prospective comparative study of subjects with narrow anterior chamber angles who underwent laser peripheral iridotomies (LPIs). The IOP was measured before and one hour after the LPI. The retinal vessel densities of the macula and ONH were measured using OCTA at the baseline and one hour after the LPI. RESULTS: A total of 64 eyes of 51 individuals were enrolled in this study, and 58 eyes of 43 individuals finally completed the study with a mean IOP rise of 10.5 ± 7.6 mmHg after the LPI. Based on the magnitude of the rise in the IOP, we divided the subjects into three groups: group A = IOP rise ≤10 mmHg, group B = 10 mmHg < IOP rise ≤20 mmHg, and group C = IOP rise > 20 mmHg. The vessel density did not differ after the acute IOP elevation in either the macular region or papillary region in group A or group B (p > 0.05), but there was a significant difference in group C (p < 0.05). However, when the subjects were not separated into groups, the vessel densities of the ONH and macular region did not differ between the measurements obtained at the baseline and one hour after the LPI (p > 0.05). The correlation existed in peripapillary and macular vessel density (p < 0.05). CONCLUSION: In these subjects with narrow antenior chamber, an acute mild or moderate IOP elevation for one hour after the LPI did not affect the vessel density in the macula or ONH, as examined using OCTA. However, when the IOP rise was greater than 20 mmHg, the macular and papillary vessel density decreased significantly.


Assuntos
Câmara Anterior/patologia , Hipertensão Ocular/patologia , Vasos Retinianos/patologia , Doença Aguda , Idoso , Feminino , Humanos , Pressão Intraocular/fisiologia , Macula Lutea/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Disco Óptico/irrigação sanguínea , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos
9.
Minerva Med ; 109(1): 15-23, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28750499

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer-related death worldwide. Exosomes are secreted membrane vesicles that play important roles in various diseases by transporting proteins and RNAs, including microRNAs, between cells. However, the function of exosomal miRNA in HCC has not been fully investigated. METHODS: Exosomes were obtained from the sera by ultracentrifugation and were processed for transmission electron microscopy (TEM). Real time PCR were revealed changes of miRNA between patients and normal donors. Predicted targets of miRNA were described by bioinformatics analysis, luciferase reporter assay was used to confirmed whether miR-9-3p regulates target expression. And then miRNA were over-expressed in HCC cell line to study its function, western blotting were used to test expression of miRNA targets, Cell viability and proliferation were analyzed after over-expressed miR-9-3p using MTT and BrdU assay. RESULTS: Serum exosomes from patients with HCC contained significantly lower levels of the miR-9-3p than did serum exosomes from normal donors, suggesting a potential role for this microRNA in HCC. Bioinformatics analysis identified fibroblast growth factor 5 (HBGF-5), which plays an important role in cell proliferation, as a potential miR-9-3p target mRNA. Luciferase reporter assay confirming that miR-9-3p can directly regulate HBGF-5 expression. Consistent with this finding, overexpression of miR-9-3p in three HCC cell lines significantly downregulated HBGF-5 expression at both the mRNA and protein levels. Finally, overexpression of miR-9-3p reduced HCC cell viability and proliferation, and additionally reduced ERK1/2 expression, suggesting a potential mechanism by which miR-9-3p acts. CONCLUSIONS: These results provide new insight into the functions of miR-9-3p and HBGF-5 in HCC and identify miR-9-3p as a potential therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Fator 5 de Crescimento de Fibroblastos/genética , Neoplasias Hepáticas/genética , MicroRNAs/fisiologia , Biomarcadores Tumorais/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Células Tumorais Cultivadas
10.
Ying Yong Sheng Tai Xue Bao ; 28(2): 589-602, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29749168

RESUMO

This study applied a grey predicting model to predict the trend of cotton fiber quality for next 5 and 10 years in the Yellow River Valley (YeRV), the Yangtze River Valley (YaRV) and the Northwest Inland Region (NWIR) based on the data set from the fiber quality traits of candidate cultivars in National Cotton Variety Regional Trials during 2005-2014. The temporal and spatial distributions of cotton trails in the three major cotton producing regions were analyzed. The results showed that the overall fiber quality of the Regional Cotton Variety Trials was improved during 2005-2014. Fiber length showed excellence and the distribution of threshold increased to 27.0-32.0 mm, and the fiber length of most cultivars reached 29 or 30 mm. Fiber strength also showed an increase trend. The proportion of high level (31.0 cN·tex-1) cultivars in YaRV was as high as 61.1% in 2011. Micronaire was significantly different among the three major cotton producing regions. In YeRV, micronaire was increased from class B2(4.3-4.9) to class C2(≥5.0). In YaRV, it maintained in a high level of class C2; while it performed excellent in class A (3.7-4.2) and B2 (4.3-4.9) in NWIR. As a comprehensive fiber quality trait, spinning consistency index decreased from NWIR, YaRV to YeRV, and was ranged from 130 to 149, which was suitable for 40-50 spun yarn and accounted for about 80.0% over the total. We concluded that NWIR had the best fiber quality, followed by YaRV and YeRV in recent ten years. In the near future, fiber quality in the regional cotton variety trails would slightly increase in YaRV, but significantly decrease in YeRV and NWIR. These changes should be highly concerned for breeders, the committee of National Cotton Variety Regional Trials and approval of management department in China.


Assuntos
Fibra de Algodão , Meio Ambiente , China , Gossypium , Fenótipo
11.
Chin J Nat Med ; 14(4): 303-307, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27114319

RESUMO

The present study aimed at isolation and purification of the bioactive terpenoids from the herb of Leonurus japonicus by chromatographic separations such as silica gel, sephadex LH-20 and C18 reversed phase silica gel, as well as preparative HPLC. As a result, leojaponic acids A (1, C17H24O4) and B (2, C18H26O4), two homologous terpenoids, together with (-)-loliolide (3), 1-(3-ethylphenyl) ethane-1, 2-diol (4) and dibutyl phthalate (5), were isolated from the EtOH extract of L. japonicus. All the chemical structures of the isolates were elucidated on the basis of 1D and 2D NMR analyses. Compounds 1 and 2 were new terpenoids, and Compounds 3 and 4 were isolated and identified for the first time from this plant. In addition, the α-glucosidase and tyrosinase inhibitory activity of the new compounds were evaluated.


Assuntos
Leonurus/química , Extratos Vegetais/química , Terpenos/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Frutas/química , Glucosidases/análise , Glucosidases/antagonistas & inibidores , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Terpenos/isolamento & purificação
12.
Tumour Biol ; 34(5): 2989-94, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23733202

RESUMO

The X-ray repair cross-complementation group 1 (XRCC1) protein plays an important role in base excision repair, and the genetic polymorphisms in the XRCC1 gene influence its function. XRCC1 codon 280 polymorphism is an Arg-His change in the XRCC1 gene. Many studies were published to investigate the association between XRCC1 codon 280 polymorphism and risk of lung cancer, but the results were inconsistent. We performed a meta-analysis of 16 studies with a total of 18,660 subjects (8,736 cases and 9,924 controls). The pooled odds ratios (OR) and corresponding 95 % confidence intervals (95 % CI) for the gene-disease association were calculated. Overall, there was a significant association between XRCC1 codon 280 polymorphism and increased risk of lung cancer (HisHis vs. ArgArg: OR = 1.53, 95 % CI 1.08-2.16, P = 0.016; HisHis vs. ArgArg/ArgHis: OR = 1.55, 95 % CI 1.10-2.19, P = 0.012). However, subgroup analysis by race failed to confirm the obvious association in Europeans and Asians. Therefore, there is a significant association between XRCC1 codon 280 polymorphism and increased risk of lung cancer. More studies with a large sample are needed to further evaluate the possible race-specific effect in the association above.


Assuntos
Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Códon , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Razão de Chances , Fatores de Risco
13.
PLoS One ; 8(5): e64389, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717608

RESUMO

Gene regulation remains one of the major challenges for gene therapy in clinical trials. In the present study, we first generated a binary tetracycline-on (Tet-On) system based on two lentivirus vectors, one expressing both human glial cell line-derived neurotrophic factor (hGDNF) and humanized recombinant green fluorescent protein (hrGFP) genes under second-generation tetracycline response element (TRE), and the other expressing the advanced reverse tetracycline-controlled transactivator--rtTA2S-M2 under a human minimal cytomegalovirus immediate early (CMV-IE) promoter. This system allows simultaneous expression of hGDNF and hrGFP genes in the presence of doxycycline (Dox). Human bone marrow-derived mesenchymal stem cells (hMSCs) were transduced with the binary Tet-On lentivirus vectors and characterized in vitro in the presence (On) or absence (Off) of Dox. The expression of hGDNF and hrGFP transgenes in transduced hMSCs was tightly regulated as determined by flow cytometry (FCM), GDNF enzyme-linked immunosorbent assay (ELISA) and quantitative real time-polymerase chain reaction (qRT-PCR). There was a dose-dependent regulation for hrGFP transgene expression. The levels of hGDNF protein in culture medium were correlated with the mean fluorescence intensity (MFI) units of hrGFP. The levels of transgene background expression were very low in the absence of Dox. The treatment of the conditioned medium from cultures of transduced hMSCs in the presence of Dox protected SH-SY5Y cells against 6-hydroxydopamine (6-OHDA) toxicity as determined by cell viability using 3, [4,5-dimethylthiazol-2-yl]-diphenyltetrazolium bromide (MTT) assay. The treatment of the conditioned medium was also found to improve the survival of dopaminergic (DA) neurons of ventral mesencephalic (VM) tissue in serum-free culture conditions as assessed by cell body area, the number of neurites and dendrite branching points, and proportion of tyrosine hydroxylase (TH)-immunoreactive (IR) cells. Our inducible lentivirus-mediated hGDNF gene delivery system may provide useful tools for basic research on gene therapy for chronic neurological disorders such as Parkinson's disease (PD).


Assuntos
Células da Medula Óssea/metabolismo , Dopamina/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Lentivirus/genética , Células-Tronco Mesenquimais/metabolismo , Fármacos Neuroprotetores , Diferenciação Celular , Meios de Cultivo Condicionados , Doxiciclina/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Vetores Genéticos , Humanos , Técnicas In Vitro , Células-Tronco Mesenquimais/citologia , Reação em Cadeia da Polimerase em Tempo Real , Transgenes
14.
PLoS One ; 8(5): e63876, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23667683

RESUMO

We have recently demonstrated that adeno-associated virus serotype 9 (AAV9)-mediated human erythropoietin (hEPO) gene delivery into the brain protects dopaminergic (DA) neurons in the substantia nigra in a rat model of Parkinson's disease. In the present study, we examined whether pre-exposure to AAV9-hEPO vectors with an intramuscular or intrastriatal injection would reduce AAV9-mediated hEPO transduction in rat brain. We first characterized transgene expression and immune responses against AAV9-hEPO vectors in rat striatum at 4 days, 3 weeks and 6 months, and with doses ranging from 10(11) to 10(13) viral genomes. To sensitize immune system, rats received an injection of AAV9-hEPO into either the muscle or the left striatum, and then sequentially an injection of AAV9-hEPO into the right striatum 3 weeks later. We observed that transgene expression exhibited in a time course and dose dependent manner, and inflammatory and immune responses displayed in a time course manner. Intramuscular, but not intrastriatal injections of AAV9-hEPO resulted in reduced levels of hEPO transduction and increased levels of the major histocompatibility complex (MHC) class I and class II antigen expression in the striatum following AAV9-hEPO re-administration. There were infiltration of the cluster of differentiation 4 (CD4)-and CD8-lymphacytes, and accumulation of activated microglial cells and astrocytes in the virally injected striatum. In addition, the sera from the rats with intramuscular injections of AAV9-hEPO contained greater levels of antibodies against both AAV9 capsid protein and hEPO protein than the other treatment groups. hEPO gene expression was negatively correlated with the levels of circulating antibodies against AAV9 capsid protein. Intramuscular and intrastriatal re-administration of AAV9-hEPO led to increased numbers of red blood cells in peripheral blood. Our results suggest that pre-immunization with an intramuscular injection can lead to the reduction of transgene expression in the striatal re-administration.


Assuntos
Corpo Estriado/metabolismo , Eritropoetina/metabolismo , Vetores Genéticos/imunologia , Imunização/métodos , Transdução Genética/métodos , Animais , Dependovirus/genética , Eritropoetina/administração & dosagem , Eritropoetina/genética , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Humanos , Injeções Intramusculares , Complexo Principal de Histocompatibilidade/genética , Testes de Neutralização , Ratos , Transgenes/genética
15.
Phys Chem Chem Phys ; 14(47): 16424-32, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23133838

RESUMO

Aimed at searching for highly active and stable nano-scale Pt-based catalysts that can improve significantly the energy conversion efficiency of direct ethanol fuel cells (DEFCs), a novel Pt-PbO(x) nanocomposite (Pt-PbO(x) NC) catalyst with a mean size of 3.23 nm was synthesized through a simple wet chemistry method without using a surfactant, organometallic precursors and high temperature. Electrocatalytic tests demonstrated that the as-prepared Pt-PbO(x) NC catalyst possesses a much higher catalytic activity and a longer durability than Pt nanoparticles (nm-Pt) and commercial Pt black catalysts for ethanol electrooxidation. For instance, Pt-PbO(x) NC showed an onset potential that was 30 mV and 44 mV less positive, together with a peak current density 1.7 and 2.6 times higher than those observed for nm-Pt and Pt black catalysts in the cyclic voltammogram tests. The ratio of current densities per unit Pt mass on Pt-PbO(x) NC, nm-Pt and Pt black catalysts is 27.3 : 3.4 : 1 for the long-term (2 hours) chronoamperometric experiments measured at -0.4 V (vs. SCE). In situ FTIR spectroscopic studies revealed that the activity of breaking C-C bonds of ethanol of the Pt-PbO(x) NC is as high as 5.17 times that of the nm-Pt, which illustrates a high efficiency of ethanol oxidation to CO(2) on the as-prepared Pt-PbO(x) NC catalyst.

16.
PLoS One ; 7(7): e41226, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22815976

RESUMO

Human albumin has recently been demonstrated to protect brain neurons from injury in rat ischemic brain. However, there is no information available about whether human albumin can prevent loss of tyrosine hydroxylase (TH) expression of dopaminergic (DA) neurons induced by 6-hydroxydopamine (6-OHDA) toxicity that is most commonly used to create a rat model of Parkinson's disease (PD). In the present study, two microliters of 1.25% human albumin were stereotaxically injected into the right striatum of rats one day before or 7 days after the 6-OHDA lesion in the same side. D-Amphetamine-induced rotational asymmetry was measured 7 days, 3 and 10 weeks after 6-OHDA lesion. We observed that intrastriatal administration of human albumin significantly reduced the degree of rotational asymmetry. The number of TH-immunoreactive neurons present in the substantia nigra was greater in 6-OHDA lesioned rats following human albumin-treatment than non-human albumin treatment. TH-immunoreactivity in the 6-OHDA-lesioned striatum was also significantly increased in the human albumin-treated rats. To examine the mechanisms underlying the effects of human albumin, we challenged PC12 cells with 6-OHDA as an in vitro model of PD. Incubation with human albumin prevented 6-OHDA-induced reduction of cell viability in PC12 cell cultures, as measured by MTT assay. Furthermore, human albumin reduced 6-OHDA-induced formation of reactive oxygen species (ROS) and apoptosis in cultured PC12 cells, as assessed by flow cytometry. Western blot analysis showed that human albumin inhibited 6-OHDA-induced activation of JNK, c-Jun, ERK, and p38 mitogen-activated protein kinases (MAPK) signaling in PC12 cultures challenged with 6-OHDA. Human albumin may protect against 6-OHDA toxicity by influencing MAPK pathway followed by anti-ROS formation and anti-apoptosis.


Assuntos
Albuminas/química , Oxidopamina/farmacologia , Doença de Parkinson/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Caspase 3/metabolismo , Linhagem Celular Tumoral , Dextroanfetamina/farmacologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Técnicas In Vitro , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Fatores de Tempo
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 31(11): 1215-8, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21176678

RESUMO

OBJECTIVE: To determine the survival rate of HIV/AIDS patients after receiving free antiretroviral treatment in Dehong prefecture, Yunnan province. METHODS: A retrospective cohort analysis was conducted on all the HIV/AIDS patients aged over 16 years who had started antiretroviral treatment during January 2007 throughout December 2009 in Dehong prefecture. RESULTS: A total of 3103 HIV/AIDS patients had received antiretroviral treatment during the study period. Among them, the mean age was (36.0 ± 9.9) years and 62.4% were males. 66.2% of them were infected with HIV through heterosexual transmission, and the mean treatment follow-up time was 21.7 months. Most patients well complied with the treatment, i.e., the average times of not taking the medicine were less than 5 per month. The cumulative survival rate of antiretroviral treatment after 1, 2, 3, 4, and 5 years were 0.95, 0.94, 0.93, 0.92, and 0.92, respectively. Data from the Cox proportional hazard regression model analysis indicated that, after adjustment for age, gender, and marital status, the baseline CD4(+)T cell counts and transmission route could significantly predicate the rates of survival. Those who were with baseline CD4(+)T cell counts as 200 - 350/mm(3)were less likely to die of AIDS than those with CD4(+) T cell counts < 200/mm(3) (Hazard Ratio or HR = 0.16, 95%CI: 0.09 - 0.28), and HIV-infected through mother-to-child transmission or routes other than heterosexual transmission were less likely to die of AIDS than through injecting drug use (HR = 0.35, 95%CI: 0.13 - 1.00). CONCLUSION: Free antiretroviral treatment had significantly improved the survival of HIV/AIDS patients. Earlier initiation of antiretroviral treatment was likely to have achieved better survival effects.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , Síndrome de Imunodeficiência Adquirida/tratamento farmacológico , China , Infecções por HIV/tratamento farmacológico , Humanos , Estudos Retrospectivos , Análise de Sobrevida
18.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): o282, 2010 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-21579718

RESUMO

The title compound, C(14)H(11)ClN(2)O(3)S, with fused thiophene and pyran rings, was synthesized via the condensation of dihydro-thio-phen-3(2H)-one 1,1-dioxide and 2-(3-chloro-benz-yl-idene)malononitrile catalysed by triethyl-amine in ethanol. The thio-phene ring adopts an envelope conformation and the pyran ring is planar (r.m.s. deviation = 0.0067 Å). The dihedral angle between the pyran and phenyl rings is 80.8 (1)°. The crystal packing is stabilized by inter-molecular N-H⋯N and N-H⋯O hydrogen bonds in which the cyano N and sulphone O atoms, respectively, acting as acceptors.

19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2421, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588746

RESUMO

In the title compound, C(14)H(11)BrF(3)N(5)O(2), the pyrimidine ring adopts a flattened envelope conformation with sp(3)-hybridized carbon as the flap [deviation = 0.177 (3) Å]. The dihedral angle between tetra-zole and bromo-phenyl rings is 84.3 (1)°. In the crystal, mol-ecules are linked into centrosymmetric dimers by pairs of N-H⋯N hydrogen bonds.

20.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2448, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588769

RESUMO

In the title compound, C(15)H(11)N(3)O(4)S, the dihedral angle between the mean planes of the dihydro-indol-2-one (r.m.s. deviation = 0.015 Å) and dihydro-thieno[3,2-b]pyran (r.m.s. deviation = 0.011 Å) ring systems is 89.53 (3)°. The crytal packing is consolidated by inter-molecular N-H⋯O and N-H⋯N hydrogen bonds, which link the mol-ecules into a two-dimensional network into sheets lying parallel to (100).

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