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141.
Vijayalakshmi D Dhandapani R Jayaveni S Jithendra PS Rose C Mandal AB 《Journal of ethnopharmacology》2012,141(1):542-546
Aim of the study
The anti-inflammatory activity of Aloe vera was investigated through MMP inhibition studies. The effect of Aloe vera on MMP-9 inhibition was tested on peripheral blood mononuclear cells (PBMC).Materials and methods
Peripheral blood mononuclear cells (PBMC) were isolated from the heparinised venous blood by Ficoll Diatrizoate gradient centrifugation. The cell count and viability was determined using dye exclusion technique. Cytotoxicity was evaluated by MTT assay. Activation of MMP-9 was visualized by gelatin zymography. Inhibition of MMP-9 in the presence of aqueous extract of Aloe vera was detected by gelatin zymography and confirmed by RT-PCR.Results
Peripheral blood mononuclear cells (PBMC) showed significant inhibition in the activity of MMP-9, indicating the in vitro inhibitory effect of Aloe vera on MMP-9. Zymographic analysis and RT-PCR showed that it caused a significant reduction in the production of MMP-9 in a concentration dependent manner.Conclusion
The inhibition of MMP-9 production in the cells was detected by gelatin zymography and was confirmed by RT-PCR. 相似文献142.
Transseptal puncture was accomplished with difficulty at an unfavorable site in a case of severe mitral stenosis with distorted atrial and septal anatomy. Septal balloon entrapment could not be avoided during attempts to cross the mitral valve using the standard technique. This problem was circumvented by resorting to the loop method and the left ventricle was entered first with a guidewire, which then supported the balloon catheter. Successful mitral valve dilatation could thus be performed. A simple alternative method that was used to form the Inoue balloon catheter into a loop is also described. 相似文献
143.
A widely used clinical recommendation is that in the presence of medial collateral ligament injuries, two-part radial head fractures should be fixed rather than excising or replacing the radial head. Direct biomechanical data comparing fracture fixation, radial head replacement and excision in a human cadaveric elbow model, have not been previously described. Such comparison is clinically important as with the increasing availability of radial head implants and promising follow up results, the role of radial head replacement in fracture management may have to be redefined. In this study, five fresh cadaveric elbows had radial head fracture creation and medial collateral ligament division, fracture fixation, radial head replacement and excision. Valgus and varus laxity were determined using an electromagnetic tracking system. Radial head replacement leads to a similar valgus (P=0.80) [corrected] laxity as compared to radial head fixation. Radial head excision resulted in a significantly greater valgus laxity as compared to radial head fixation (P=0.02) or replacement (P=0.03). Both radial head excision and replacement led to a greater varus laxity as compared to fixation. Our results suggest that in the elbow with medial collateral ligament injury and two-part radial head fracture, fixation is overall biomechanically superior as compared to replacement and excision. 相似文献
144.
Gingiva from alloxan and streptozotocin-diabetic rats exhibited markedly enhanced collagenolytic activity in tissue culture. This effect was eliminated by puromycin or by repeated freeze-thawing of the tissue prior to incubation. Soluble extracts of the diabetic gingiva in situ were found to contain breakdown products of collagen similar in size to the reaction products generated by tissue collagenase. These fragments were not detected in the control tissue. This study indicates that experimental diabetes stimulates the synthesis of gingival collagenase in culture and that a similar effect occurs in vivo. 相似文献
145.
Revathidevi Sundaramoorthy Manikandan Mayakannan Rao Arunagiri Kuha Deva Magendhra Vinothkumar Vilvanathan Arunkumar Ganesan Rajkumar Kottayasamy Seenivasagam Ramani Rajendran Rajaraman Ramamurthy Ajay Chandrasekar Munirajan Arasambattu Kannan 《Tumour biology》2016,37(9):11983-11990
Tumor Biology - Breast cancer and cervical cancer are the leading causes of death in women worldwide as well as in India, whilst oral cancer is the top most common cancer among Asian especially in... 相似文献
146.
147.
A Christian Whelen Kent Kitagawa Jay Maddock Donald Hayes Tonya Lowery St John Ranjani Rajan 《Hawai'i Journal of Medicine & Public Health》2013,72(1):27-30
Chronically understaffed public health laboratories depend on a decreasing number of employees who must assume broader responsibilities in order to sustain essential functions for the many clients the laboratories support. Prospective scientists considering a career in public health are often not aware of the requirements associated with working in a laboratory regulated by the Clinical Laboratory Improvement Amendments (CLIA). The purpose of this pilot internship was two-fold; introduce students to operations in a regulated laboratory early enough in their academics so that they could make good career decisions, and evaluate internship methodology as one possible solution to workforce shortages. Four interns were recruited from three different local universities, and were paired with an experienced State Laboratories Division (SLD) staff mentor. Students performed tasks that demonstrated the importance of CLIA regulations for 10–15 hours per week over a 14 week period. Students also attended several directed group sessions on regulatory lab practice and quality systems. Both interns and mentors were surveyed periodically during the semester. Surveys of mentors and interns indicated overall positive experiences. One-on-one pairing of experienced public health professionals and students seems to be a mutually beneficial arrangement. Interns reported that they would participate if the internship was lower paid, unpaid, or for credit only. The internship appeared to be an effective tool to expose students to employment in CLIA-regulated laboratories, and potentially help address public health laboratory staffing shortfalls. Longer term follow up with multiple classes of interns may provide a more informed assessment. 相似文献
148.
Mwansa JC Mwaba J Lukwesa C Bhuiyan NA Ansaruzzaman M Ramamurthy T Alam M Balakrish Nair G 《Epidemiology and infection》2007,135(5):847-853
Antibiotic resistance data, made available from laboratory records during eight cholera outbreaks between 1990 and 2004 showed Vibrio cholerae serogroup O1 to have a low level of resistance (2-3%) to tetracycline during 1990-1991. Resistance increased for tetracycline (95%), chloramphenicol (78%), doxycycline (70%) and trimethoprim-sulphamethoxazole (97%) in subsequent outbreaks. A significant drop in resistance to tetracycline and chloramphenicol followed the adoption of a national policy to replace tetracycline with erythromycin for treating cholera. Sixty-nine strains from cholera outbreaks in Zambia between 1996 and 2004, were examined for antibiotic resistance and basic molecular traits. A 140 MDa conjugative, multidrug-resistant plasmid was found to encode tetracycline resistance in strains from 1996/1997 whereas strains from 2003/2004 were resistant to furazolidone, but susceptible to tetracycline, and lacked this plasmid. PCR revealed 25 of 27 strains from 1996/1997 harboured the intl1 class 1 integron but lacked SXT, a conjugative transposon element. Similar screening of 42 strains from 2003/2004 revealed all carried SXT but not the intl1 class 1 integron. All 69 strains, except two, one lacking ctxA and the other rstR and thus presumably truncated in the CTX prophage region, were positive for important epidemic markers namely rfbO1, ctxA, rstR2, and tcpA of El Tor biotype. Effective cholera management is dependent on updated reports on culture and sensitivity to inform the choice of antibiotic. Since the emergence of antibiotic resistance may significantly influence strategies for controlling cholera, continuous monitoring of epidemic strains is crucial. 相似文献
149.
Synovial procollagenase activation by human mast cell tryptase dependence upon matrix metalloproteinase 3 activation. 总被引:10,自引:2,他引:10 下载免费PDF全文
B L Gruber M J Marchese K Suzuki L B Schwartz Y Okada H Nagase N S Ramamurthy 《The Journal of clinical investigation》1989,84(5):1657-1662
Mast cells have been implicated in the pathogenesis of the matrix degradation observed in the cartilaginous and osseous structures of the rheumatoid joint. We previously reported that human mast cell tryptase, a 134-kD granule-associated neutral protease, is present in rheumatoid synovium and can activate collagenase in crude culture medium in vitro. the present study attempts to depict the precise mechanism of this activation. To express full activation of latent collagenase, matrix metalloproteinase 3 (MMP-3) or stromelysin, can be activated by tryptase in a time and dose-dependent manner. Tryptase was not capable of generating active collagenase in the crude media from cultured rheumatoid synoviocytes depleted of proMMP-3 by immunoadsorption. In addition, the function of the tissue inhibitor of metalloproteinases (TIMP) was not altered by tryptase, and SDS-PAGE analysis revealed no degradation of TIMP by tryptase. The tryptase dependent activation of synoviocyte procollagenase thereby appears to be entirely dependent upon its ability to activate proMMP-3. 相似文献
150.
Puneet Agarwal Yuk Hei Wong Esha Dasgupta Renu Agarwal Bethel Indira Livingstone Srinivasan Ramamurthy 《Cutaneous and ocular toxicology》2015,34(3):179-184
Background: Hydroxychloroquine (HCQ) is widely used for long-term treatment of autoimmune diseases such as rheumatoid arthritis. However, its long-term use is known to be associated with visual changes due to retinal damage. Retinal damage associated with long-term HCQ therapy is preventable if the drug is discontinued early when the patients are still asymptomatic. In view of contrasting reports from previous studies, we investigated the association of prolonged HCQ therapy with retinal thickness in macular area.Methods: This study included 48 patients on long-term HCQ therapy and 38 healthy controls. All subjects underwent examination for corrected visual acuity, fundus photography, visual fields and SD-OCT for retinal thickness.Results: Visual acuity, visual fields, fundus photography and SD-OCT did not reveal changes consistent with diagnosis of established HCQ retinopathy in any of the subjects from HCQ group. Retinal thickness in central, parafoveal and perifoveal areas did not show significant differences between HCQ and control groups. However, we observed negative correlation between cumulative dose and retinal thickness in the parafoveal (p?=?0.003) and perifoveal areas (p?=?0.019) but not in the central area.Conclusions: Correlation of cumulative dose with retinal thickness in parafoveal and perifoveal areas and not the central area is in accordance with the late appearance of HCQ-induced bull's eye retinopathy. Hence screening of asymptomatic patients using OCT seems to be of great importance for early detection of retinal changes. 相似文献