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101.
Effect of gamma-interferon on collagen synthesis by normal and fibrotic human lung fibroblasts. 总被引:4,自引:0,他引:4
Increased lung collagen and increased collagen synthesis by lung fibroblasts is well recognized in pulmonary fibrosis. gamma-Interferon has been shown to inhibit collagen synthesis by fibroblasts. To understand its effect on lung fibroblasts we compared how this lymphokine affects the growth and collagen synthesis of normal and fibrotic human lung fibroblasts. The results showed that gamma-IFN inhibited DNA synthesis in all fibroblast strains examined. Both collagen production and type 1 mRNA levels were reduced in three normal and two fibrotic cell strains exposed to gamma-IFN, while they were not affected in one strain from fibrotic lung. Even though an occasional cell was unaffected by the gamma-IFN, collagen mRNA level was reduced in most cells and it remained reduced for 48 h after removing the gamma-IFN. These results show that gamma-IFN inhibits the growth of fibroblast cultures derived from normal and fibrotic human lungs and suppresses collagen synthesis in most of these cells. 相似文献
102.
Sujata Narayanan Neeraj Agarwal Kristina Callis-Duffin Julia Batten 《The American journal of the medical sciences》2010,339(6):580-581
Sunitinib is an oral tyrosine kinase inhibitor, which is indicated for the treatment of renal cell carcinoma and gastrointestinal stromal tumors. The authors report the case of a patient who underwent treatment for renal cell carcinoma and noted additional benefit by improvement in his psoriatic skin lesions. This may be attributed to the antiangiogenic activity of sunitinib by inhibition of vascular endothelial growth factor receptors. 相似文献
103.
104.
Naduthottam Palaniswami Kamalesh Kurumboor Prakash Kaniyarakal Pramil Prakash Zacharias Ganesh Narayanan Ramesh Mathew Philip 《Indian journal of gastroenterology》2012,31(6):337-339
The prevalence of diverticular disease of colon of colon is reportedly low in Asian compared to Western countries. We analyzed the prevalence of colonic diverticulosis in a selected cohort of patients undergoing colonoscopy. Retrospective study of records of patients undergoing colonoscopy in a tertiary hospital in southern India. 相似文献
105.
106.
Sien Hui Tan Aun Wee Chong Abdul Rahman Nazarina Narayanan Prepageran 《Otolaryngologia polska. The Polish otolaryngology》2014
We describe a rare case of BSCC in the retromolar trigone with only 3 other cases in the literature and also compare the differences between 2 cases of BSCC in terms of presentation and progression. The first patient had a markedly slower progression with painful retromolar trigone swelling over 4 months without nodal metastases. In contrast, the second patient gave a 2-week history of neck swelling with nodal involvement, indicating extremely rapid progression. Our management was tailored accordingly with the first patient undergoing intraoral excision of tumour and adjuvant radiotherapy while the other had bilateral neck dissection with postoperative chemoradiotherapy. Both patients achieved good outcome and are free from disease. 相似文献
107.
Yoon‐Chul Kim Cecil E. Hayes Shrikanth S. Narayanan Krishna S. Nayak 《Magnetic resonance in medicine》2011,65(6):1711-1717
Upper airway MRI can provide a noninvasive assessment of speech and swallowing disorders and sleep apnea. Recent work has demonstrated the value of high‐resolution three‐dimensional imaging and dynamic two‐dimensional imaging and the importance of further improvements in spatio‐temporal resolution. The purpose of the study was to describe a novel 16‐channel 3 Tesla receive coil that is highly sensitive to the human upper airway and investigate the performance of accelerated upper airway MRI with the coil. In three‐dimensional imaging of the upper airway during static posture, 6‐fold acceleration is demonstrated using parallel imaging, potentially leading to capturing a whole three‐dimensional vocal tract with 1.25 mm isotropic resolution within 9 sec of sustained sound production. Midsagittal spiral parallel imaging of vocal tract dynamics during natural speech production is demonstrated with 2 × 2 mm2 in‐plane spatial and 84 ms temporal resolution. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
108.
L. Deepanandan Vinod Narayanan M. F. Baig 《Journal of maxillofacial and oral surgery》2010,9(1):48-53
Aim
Carcinoma of the mandibular region can be considered as an important, distinct entity associated with special problems relating to diagnosis, evaluation of extension, planning of treatment, surgical techniques, treatment result and prognosis. The study was aimed to assess the accuracy of computerized tomography in demonstrating mandibular invasion, to assess the role of anatomic structures like cancellous spaces, the inferior alveolar nerve and periodontal spaces in spread of carcinomas in the mandible and to determine the spread of tumour within the mandible and the resection procedure to be carried. 相似文献109.
Bhagavathi A Narayanan Bandaru S Reddy Maarten C Bosland Dominick Nargi Lori Horton Carla Randolph Narayanan K Narayanan 《Clinical cancer research》2007,13(19):5965-5973
PURPOSE: Nonsteroidal anti-inflammatory drugs mediate anticancer effects by modulating cyclooxygenase-2 (COX-2)-dependent and/or COX-2-independent mechanism(s); however, the toxicity issue is a concern with single agents at higher doses. In this study, we determined the combined effect of celecoxib, a COX-2 inhibitor, along with exisulind (sulindac sulfone/Aptosyn) at low doses in prostate cancer. EXPERIMENTAL DESIGN: We used a sequential regimen of N-methyl-N-nitrosourea + testosterone to induce prostate cancer in Wistar-Unilever rats. Following carcinogen treatment, celecoxib and exisulind individually and their combination at low doses were given in NIH-07 diet for 52 weeks. We determined the incidence of prostatic intraepithelial neoplasia, adenocarcinomas, rate of tumor cell proliferation, and apoptosis. Immunohistochemical and Western blot analysis were done to determine COX-2, epidermal growth factor receptor (EGFR), Akt, androgen receptor, and cyclin D1 expression. Serum prostaglandin E2 and tumor necrosis factor-alpha levels were determined using enzyme immunoassay/ELISA assays. RESULTS: The rats that received celecoxib in combination with exisulind at low doses showed a significant decrease in prostatic intraepithelial neoplasia and adenocarcinomas as well as an enhanced rate of apoptosis. An overall decrease in COX-2, EGFR, Akt, androgen receptor, and cyclin D1 expression was found associated with tumor growth inhibition. Reduced serum levels of COX-2 protein, prostaglandin E2, and tumor necrosis factor-alpha indicated anti-inflammatory effects. A strong inhibition of total and phosphorylated form of EGFR (Tyr(992) and Tyr(845)) and Akt (Ser(473)) was significant in rats given with these agents in combination. CONCLUSIONS: In this study, we show for the first time that the combination of celecoxib with exisulind at low doses could prevent prostate carcinogenesis by altering key molecular events. 相似文献
110.
Bhandarkar PV Shah SK Meshram M Abraham P Narayanan TS Bhatia SJ 《Journal of gastroenterology and hepatology》2000,15(9):1018-1021
BACKGROUND AND AIMS: Nicotine administration is known to decrease lower oesophageal sphincter (LOS) pressure. Although a few studies have assessed the effect of tobacco on the LOS, the effect of acute and long-term oral tobacco use on oesophageal motility is not known. The study was designed to investigate the effect of acute and long-term oral tobacco use on LOS and distal oesophageal motility. METHODS: Thirty-six healthy men (aged 18-65 years, median 34 years; 18 oral tobacco users, 18 non-tobacco users) underwent oesophageal manometry using a water-perfusion system. After baseline manometry, tobacco users were asked to keep 0.5 g tobacco in their mouth for 10 min; non-users of tobacco were kept in quiet surroundings for a similar period. Manometry was then repeated. RESULTS: The LOS basal pressures were similar in tobacco users and non-tobacco users (mean +/- SD 15.4 +/- 6.3 vs 13.4 +/- 5.3 mmHg). In the distal oesophageal body, the velocity (4.4 +/- 3.1 vs 4.9 +/- 2.6 cm/s), amplitude (92.7 +/- 38.3 vs 84.8 +/- 33.2 mmHg) and duration of contraction (2.1 +/- 0.7 vs 1.7 +/- 0.9 s) were similar in tobacco users and non-users. Acute tobacco use did not affect these parameters. The numbers of abnormal waves (triple peaks and non-transmitted contractions) were also similar in the two groups. CONCLUSION: Oral tobacco use does not appear to affect LOS pressures and distal oesophageal motility acutely or in the long term. 相似文献