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排序方式: 共有1937条查询结果,搜索用时 18 毫秒
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Shalini Agnihotri Rama Devi Mittal Rakesh Kapoor Anil Mandhani 《Urologic oncology》2014,32(7):946-951
ObjectiveTo test the hypothesis that sexual dysfunction in elderly men with benign prostatic hyperplasia leads to prostatic inflammation, diagnosed by prostatic fluid interleukin-8 (IL-8), which lowers the positive predictive value of prostate-specific antigen (PSA).MethodsOverall, 160 men with lower urinary tract symptoms between 50 and 75 years of age with an elevated PSA level of more than 4 ng/ml with normal digital rectal examination and 50 age-matched controls with normal PSA level were prospectively evaluated for prostatic fluid IL-8 levels. Erectile dysfunction was measured by self-administered questionnaire of the Sexual Health Inventory for Men. Total and free serum PSA levels and IL-8 in prostatic fluid were measured 6 to 8 weeks after a course of 400 mg of ofloxacin and 20 mg of piroxicam given daily for 2 weeks. Transrectal ultrasonography–guided biopsy was done only when PSA level did not decrease less than 4 ng/ml.ResultsMean ages of patients and controls were 63.18 (standard deviation [SD]±7.10) and 60.18 (SD+6.02) years, respectively. Mean concentration of IL-8 in prostatic fluid of the patients was significantly higher, i.e., 6678 pg/ml (SD±1985.7) than in control, i.e., 1543 pg/ml (SD±375.7) (P<0.001). Following anti-inflammatory treatment, there was a significant decrease in the mean level of IL-8 from baseline to 5622 pg/ml (SD±1870.66) (P<0.001). Corresponding to this, a significant decrease was noted in total PSA levels to less than 4 ng/ml in 105 (65.62%) patients. Men with the highest levels of IL-8 had a greater degree of erectile dysfunction.ConclusionMen with symptomatic benign prostatic hyperplasia and erectile dysfunction had significant inflammation of the prostate to cause spurious rise in PSA level resulting in an unnecessary biopsy. 相似文献
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Erika Fantozzi Erlinda Rama Cinzia Calvio Benedetta Albini Pietro Galinetto Marcella Bini 《Materials》2021,14(11)
Spinel phases, with unique and outstanding physical properties, are attracting a great deal of interest in many fields. In particular, MgFe2O4, a partially inverted spinel phase, could find applications in medicine thanks to the remarkable antibacterial properties attributed to the generation of reactive oxygen species. In this paper, undoped and Ag-doped MgFe2-xAgxO4 (x = 0.1 and 0.3) nanoparticles were prepared using microwave-assisted combustion and sol–gel methods. X-ray powder diffraction, with Rietveld structural refinements combined with micro-Raman spectroscopy, allowed to determine sample purity and the inversion degree of the spinel, passing from about 0.4 to 0.7 when Ag was introduced as dopant. The results are discussed in view of the antibacterial activity towards Escherichia coli and Staphylococcus aureus, representative strains of Gram-negative and Gram-positive bacteria. The sol–gel particles were more efficient towards the chosen bacteria, possibly thanks to the nanometric sizes of metallic silver, which were well distributed in the powders and in the spinel phase, with respect to microwave ones, that, however, acquired antibacterial activity after thermal treatment, probably due to the nucleation of hematite, itself displaying well-known antibacterial properties and which could synergistically act with silver and spinel. 相似文献
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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