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61.
Smith JM Amara RR Campbell D Xu Y Patel M Sharma S Butera ST Ellenberger DL Yi H Chennareddi L Herndon JG Wyatt LS Montefiori D Moss B McClure HM Robinson HL 《AIDS research and human retroviruses》2004,20(12):1335-1347
Recently, a vaccine consisting of DNA priming followed by boosting with modified vaccinia Ankara (MVA) has provided long-term protection of rhesus macaques against a virulent challenge with a chimera of simian and human immunodeficiency viruses. Here, we report studies on the development of the DNA component for a DNA/MVA HIV vaccine for humans. Specifically, we assess the ability of a codon-optimized Gag-expressing DNA and two noncodon-optimized Gag-Pol-Env-expressing DNAs to prime the MVA booster dose. The codon-optimized DNA expressed virus-like particles (VLPs), whereas one of the noncodon-optimized DNAs expressed VLPs and the other expressed aggregates of HIV proteins. The MVA boost expressed Gag-Pol and Env and produced VLPs. Immunogenicity studies in macaques used one intramuscular prime with 600 microg of DNA and two intramuscular boosts with 1 x 10(8) pfu of MVA at weeks 8 and 30. The codon-optimized and noncodon-optimized DNAs proved similar in their ability to prime anti-Gag T cell responses. The aggregate and VLP-expressing Gag-Pol-Env DNAs also showed no significant differences in their ability to prime anti-Env Ab responses. The second MVA booster dose did not increase the peak CD4 and CD8 T cell responses, but increased anti-Env Ab titers by 40- to 90-fold. MVA-only immunizations elicited 10-100 times lower frequencies of T cells and 2-4 lower titers of anti-Env Ab than the Gag-Pol-Env DNA/MVA immunizations. Based on the breadth of the T cell response and a trend toward higher titers of anti-Env Ab, we are moving forward with human trials of the noncodon-optimized VLP-expressing DNA. 相似文献
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Mandar Bopardikar Anusri Bhattacharya Veera Mohana Rao Kakita Kavitha Rachineni Lalit C. Borde Sinjan Choudhary Sri Rama Koti Ainavarapu Ramakrishna V. Hosur 《RSC advances》2019,9(49):28470
The process of assembly and accumulation of the intrinsically disordered protein (IDP), alpha-synuclein (αSyn) into amyloid fibrils is a pathogenic process leading to several neurodegenerative disorders such as Parkinson''s disease, multiple system atrophy and others. Although several molecules are known to inhibit αSyn fibrillization, the mechanism of inhibition is just beginning to emerge. Here, we report the inhibition of fibrillization of αSyn by Triphala, a herbal preparation in the traditional Indian medical system of Ayurveda. Triphala was found to be a rich source of polyphenols which are known to act as amyloid inhibitors. ThT fluorescence and TEM studies showed that Triphala inhibited the fibrillization of αSyn. However, it was observed that Triphala does not disaggregate preformed αSyn fibrils. Further, native-PAGE showed that Triphala reduces the propensity of αSyn to oligomerize during the lag phase of fibrillization. Our NMR results showed that certain stretches of residues in the N-terminal and NAC regions of αSyn play an anchor role in the self-association process of the protein, thereby providing mechanistic insights into the early events during αSyn fibrillization.Triphala inhibits αSyn self-association by interacting with anchoring regions which are responsible for αSyn oligomerization. 相似文献
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Muthu Rama Krishnan Mookiah U. Rajendra Acharya Joel E.W. Koh Chua Kuang Chua Jen Hong Tan Vinod Chandran Choo Min Lim Kevin Noronha Augustinus Laude Louis Tong 《Medical & biological engineering & computing》2014,52(9):781-796
Age-related macular degeneration (AMD) affects the central vision and subsequently may lead to visual loss in people over 60 years of age. There is no permanent cure for AMD, but early detection and successive treatment may improve the visual acuity. AMD is mainly classified into dry and wet type; however, dry AMD is more common in aging population. AMD is characterized by drusen, yellow pigmentation, and neovascularization. These lesions are examined through visual inspection of retinal fundus images by ophthalmologists. It is laborious, time-consuming, and resource-intensive. Hence, in this study, we have proposed an automated AMD detection system using discrete wavelet transform (DWT) and feature ranking strategies. The first four-order statistical moments (mean, variance, skewness, and kurtosis), energy, entropy, and Gini index-based features are extracted from DWT coefficients. We have used five (t test, Kullback–Lieber Divergence (KLD), Chernoff Bound and Bhattacharyya Distance, receiver operating characteristics curve-based, and Wilcoxon) feature ranking strategies to identify optimal feature set. A set of supervised classifiers namely support vector machine (SVM), decision tree, \(k\) -nearest neighbor ( \(k\) -NN), Naive Bayes, and probabilistic neural network were used to evaluate the highest performance measure using minimum number of features in classifying normal and dry AMD classes. The proposed framework obtained an average accuracy of 93.70 %, sensitivity of 91.11 %, and specificity of 96.30 % using KLD ranking and SVM classifier. We have also formulated an AMD Risk Index using selected features to classify the normal and dry AMD classes using one number. The proposed system can be used to assist the clinicians and also for mass AMD screening programs. 相似文献
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Nagui S. T. Gendi Ken I. Welsh Walther J. Van Venrooij Rama Vancheeswaran Jill Gilroy Carol M. Black 《Arthritis \u0026amp; Rheumatology》1995,38(2):259-266
Objective. To determine any clinical or genetic markers of differentiation and outcome in a previously described cohort of 46 patients with mixed connective tissue disease (MCTD). Methods. Patients were clinically evaluated, chart notes reviewed, and HLA subtyping and immunology profiles performed where possible. Eleven had died and 7 were lost to followup. Results. MCTD had differentiated into systemic lupus erythematosus in 12 patients and into systemic sclerosis in 13. The latter was associated with HLA-DR5 (P = 0.038), and nondifferentiation was associated with HLA-DR2 or DR4 (P = 0.007). Three HLA-DR4 positive patients had MCTD that evolved into rheumatoid arthritis. Erosive and/or deforming arthritis was associated with HLA-DR1 or DR4 (P = 0.015). HLA-DR3 was associated with interstitial lung fibrosis (P = 0.044) and keratoconjunctivitis sicca (0.001 < P < 0.01). Severe Raynaud's phenomenon predicted higher mortality (0.01 < P < 0.05). Conclusion. We suggest that MCTD is, for most patients, an intermediate stage in a genetically determined progression to a recognized connective tissue disease. Those whose disease remains undifferentiated might be considered a distinct subset. 相似文献