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201.
Anti-dermatophytic activity of marine sponge,Sigmadocia carnosa (Dendy) on clinically isolated fungi
NB Dhayanithi TT Ajith Kumar M Kalaiselvam T Balasubramanian N Sivakumar 《Asian Pacific Journal of Tropical Biomedicine》2012,2(8):635-639
Objective
To screen the anti-fungal effects and find out the active metabolites from sponge, Sigmadocia carnosa (S. carnosa) against four dermatophytic fungi.Methods
The methanol, ethyl acetate and acetone extract of marine sponge, S. carnosa was examined against Trichophyton mentagrophytes (T. mentagrophytes), Trichophyton rubrum (T. rubrum), Epidermophyton floccosum (E. floccosum) and Microsporum gypseum (M. gypseum) and qualitative analysed to find out the active molecules.Results
The methanol extract of sponge was expressed significant activity than ethyl acetate and acetone. The minimum inhibitory concentration (MIC) of methanol extract of sponge that resulted in complete growth inhibition of T. mentagrophytes, T. rubrum, E. floccosum and M. gypseum were found to 125, 250, 250 and 250 µg/mL respectively. But, 100 % inhibition of fungal spore germination was observed in T. mentagrophytes at 500 µg/mL concentration followed by T. rubrum, E. floccosum and M. gypseum at 1 000 µg/mL concentration. Other two extracts showed weak anti spore germination activity against the tested dermatophytic fungi. Methanol extracts showed presence of terpenoids, steroids, alkaloids, saponins and glycosides.Conclusion
Based on the literature, this is the first study which has conducted to inhibit the growth and spore germination of dermatophytic fungi with S. carnosa. Further research also needs to purify and characterize the secondary metabolites from the sponge, S. carnosa for the valuable source of novel substances for future drug discovery. 相似文献202.
203.
Genital human papillomavirus infection in men: incidence and risk factors in a cohort of university students 总被引:2,自引:0,他引:2
Partridge JM Hughes JP Feng Q Winer RL Weaver BA Xi LF Stern ME Lee SK O'Reilly SF Hawes SE Kiviat NB Koutsky LA 《The Journal of infectious diseases》2007,196(8):1128-1136
BACKGROUND: In contrast to the wealth of data on human papillomavirus (HPV) infections in women, much less is known about HPV in men. METHODS: Between June 2003 and March 2006, a total of 240 heterosexually active male university students 18-20 years of age were recruited for participation in a cohort study of HPV infection. Genital cell samples were collected, at 4-month intervals, for HPV-DNA analysis by polymerase chain reaction. The subjects maintained a Web-based journal of sexual activity. RESULTS: At 24 months, the cumulative incidence of new infection of any genital HPV type was 62.4% (95% confidence interval [CI], 52.6%-72.2%). Acquisition rates did not differ by genital site (i.e., glans, penile shaft, or scrotum) of initial detection (P=.86). The most commonly detected types were HPV-84 and HPV-16. In multivariate analysis, a report of a new sex partner during the prior 0-4 (hazards ratio [HR], 2.0 [95% CI, 1.3-3.0]) and 5-8 (HR, 1.8 [95% CI, 1.2-2.7]) months and a history of smoking (HR, 1.6 [95% CI, 1.1-2.4]) were associated with an elevated risk of HPV acquisition. CONCLUSION: Genital HPV infection is common and multifocal in young men, and its incidence is higher than that reported for similar cohorts of young women. The high rates of HPV infection in men should be considered when strategies for the prevention of HPV infection in female adolescents and young women are being developed. 相似文献
204.
A cohort study of the risk of cervical intraepithelial neoplasia grade 2 or 3 in relation to papillomavirus infection. 总被引:53,自引:0,他引:53
L A Koutsky K K Holmes C W Critchlow C E Stevens J Paavonen A M Beckmann T A DeRouen D A Galloway D Vernon N B Kiviat 《The New England journal of medicine》1992,327(18):1272-1278
BACKGROUND. Human papillomavirus (HPV) has been associated with cervical intraepithelial neoplasia, but the temporal relation between the infection and the neoplasia remains unclear, as does the relative importance of the specific type of HPV, other sexually transmitted diseases, and other risk factors. METHODS. We studied prospectively a cohort of 241 women who presented for evaluation of sexually transmitted disease and had negative cervical cytologic tests. The women were followed every four months with cytologic and colposcopic examinations of the uterine cervix and tests for HPV DNA and other sexually transmitted diseases. RESULTS. Cervical intraepithelial neoplasia grade 2 or 3 was confirmed by biopsy in 28 women. On the basis of survival analysis, the cumulative incidence of cervical intraepithelial neoplasia at two years was 28 percent among women with a positive test for HPV and 3 percent among those without detectable HPV DNA. The risk was highest among those with HPV type 16 or 18 infection (adjusted relative risk as compared with that in women without HPV infection, 11; 95 percent confidence interval, 4.6 to 26; attributable risk, 52 percent). All 24 cases of cervical intraepithelial neoplasia grade 2 or 3 among HPV-positive women were detected within 24 months after the first positive test for HPV. After adjustment for the presence of HPV infection, the development of cervical intraepithelial neoplasia was also associated with younger age at first intercourse, the presence of serum antibodies to Chlamydia trachomatis, the presence of serum antibodies to cytomegalovirus, and cervical infection with Neisseria gonorrhoeae. CONCLUSIONS. Cervical intraepithelial neoplasia is a common and apparently early manifestation of cervical infection by HPV, particularly types 16 and 18. 相似文献
205.
Dana N. Raugi Robert A. Smith Selly Ba Macoumba Toure Fatou Traore Fatima Sall Charlotte Pan Lindsey Blankenship Alexandra Montano Julia Olson Ndeye Mery Dia Badiane James I. Mullins Nancy B. Kiviat Stephen E. Hawes Papa Salif Sow Geoffrey S. Gottlieb 《Antimicrobial agents and chemotherapy》2013,57(6):2751-2760
Protease inhibitor (PI)-based antiretroviral therapy (ART) can effectively suppress HIV-2 plasma load and increase CD4 counts; however, not all PIs are equally active against HIV-2, and few data exist to support second-line therapy decisions. To identify therapeutic options for HIV-2 patients failing ART, we evaluated the frequency of PI resistance-associated amino acid changes in HIV-2 sequences from a cohort of 43 Senegalese individuals receiving unboosted indinavir (n = 18 subjects)-, lopinavir/ritonavir (n = 4)-, or indinavir and then lopinavir/ritonavir (n = 21)-containing ART. Common protease substitutions included V10I, V47A, I54M, V71I, I82F, I84V, L90M, and L99F, and most patients harbored viruses containing multiple changes. Based on genotypic data, we constructed a panel of 15 site-directed mutants of HIV-2ROD9 containing single- or multiple-treatment-associated amino acid changes in the protease-encoding region of pol. We then quantified the susceptibilities of the mutants to the HIV-2 “active” PIs saquinavir, lopinavir, and darunavir using a single-cycle assay. Relative to wild-type HIV-2, the V47A mutant was resistant to lopinavir (6.3-fold increase in the mean 50% effective concentration [EC50]), the I54M variant was resistant to darunavir and lopinavir (6.2- and 2.7-fold increases, respectively), and the L90M mutant was resistant to saquinavir (3.6-fold increase). In addition, the triple mutant that included I54M plus I84V plus L90M was resistant to all three PIs (31-, 10-, and 3.8-fold increases in the mean EC50 for darunavir, saquinavir, and lopinavir, respectively). Taken together, our data demonstrate that PI-treated HIV-2 patients frequently harbor viruses that exhibit complex patterns of PI cross-resistance. These findings suggest that sequential PI-based regimens for HIV-2 treatment may be ineffective. 相似文献
206.
207.
208.
Qinghua Feng Joshua E. Stern Hiep Lu Nancy B. Kiviat 《Experimental and molecular pathology》2010,88(2):287-292
Hepatocellular carcinoma (HCC) is known to be associated with both HBV and HCV. While epigenetic changes have been previously reported to be associated with hepatocellular carcinoma (HCC), whether the epigenetic profile of HBC associated HCC differs from that of HCV-associated HCC is unclear. We analyzed DNA methylation of ten genes (APC, CCND2, CDKN2A, GSTP1, HOXA9, RARB, RASSF1, RUNX, SFRP1, and TWIST1) using MethyLight assays on 65 archived liver tissue blocks. Three genes (APC, CCND2, and GSTP1) were frequently methylated in normal liver tissues. Five genes (APC, CDKN2A, HOXA9, RASSF1, and RUNX) were significantly more frequently methylated in malignant liver tissues than normal liver tissues. Among HCC cases, HOXA9, RASSF1 and SFRP1 were methylated more frequently in HBV-positive HCC cases, while CDKN2A were significantly more frequently methylated in HCV-positive HCC cases. Our data support the hypothesis that HCC resulting from different viral etiologies is associated with different epigenetic changes. 相似文献
209.
210.
K. K. Ramalingam MB FRCS DLO Ravi Ramalingam MB MS Dip NB Kanchan Dhote MB DLO Sreenivasa Murthy T.M. MB DLO 《Indian journal of otolaryngology and head and neck surgery》2005,57(3):252-255
The endoluminal presence of thyroid tissue in the trachea is a rare cause of airway obstruction. Only 14 well documented cases of intratracheal ectopic thyroid tissue have been reported in English Literature since 1966. These lesions are mostly benign and nearly all patients present with symptoms of respiratory obstruction. We present a case of ectopic thyroid in cervical trachea presenting with symptoms of airway obstruction. Thorough clinical examination and investigations were carried out. A right hemithyroidectomy and excision of a part of the tracheal wall through a tracheotomy was performed for removal of the ectopic thyroid tissue from trachea. The clinicians & radiologists must be aware of this entity to avoid mistaking it for evidence of invasion by a malignant neoplas, and hence this report. 相似文献