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21.
Sharma T Gopal L Parikh S Shanmugam MP Saha SK Sulochana KR Shetty NS Mukesh BN Badrinath SS 《Indian journal of ophthalmology》1999,47(4):223-227
PURPOSE: To evaluate the efficacy of pH-adjusted bupivacaine in conjunction with medial orbital periconal block (periocular anaesthesia). METHODS: Sixty consecutive patients undergoing primary vitreoretinal surgery were enrolled prospectively. RESULTS: Adequate anaesthesia and akinesia with no intraoperative supplementation was achieved in 53 eyes (88.3%). Factors influencing intraoperative supplementation were combined vitrectomy with scleral buckling (p = 0.005) and duration of surgery of more than 2 hours (p = 0.001). No ocular or systemic complication resulted. CONCLUSION: pH-adjusted periocular anaesthesia is safe and effective in patients undergoing primary vitreoretinal surgery. 相似文献
22.
Awasthi S Singhal SS Pandya U Gopal S Zimniak P Singh SV Awasthi YC 《Toxicology and applied pharmacology》1999,155(3):215-226
We have recently demonstrated mutually inhibitory ATP-dependent transport of dinitrophenyl-S-glutathione (DNP-SG) and doxorubicin by DNP-SG ATPase purified from human erythrocyte membranes (S. Awasthi et al., 1998a,b). Our previous studies indicate a broad substrate specificity for this transport mechanism, including some P-glycoprotein substrates. Present studies were carried out to determine whether colchicine (COL), a classical P-glycoprotein substrate, could be transported by purified human erythrocyte DNP-SG ATPase reconstituted in artificial liposomes. We also investigated whether leukotriene C4 (LTC4), an endogenous proinflammatory glutathione-conjugate derived from arachidonic acid, would inhibit colchicine transport. Uptake of COL was compared in proteoliposomes reconstituted with the purified DNP-SG ATPase as well as control liposomes in the presence or absence of ATP. Increased colchicine uptake was observed upon addition of ATP to proteoliposomes, but not control liposomes. Uptake was linear with respect to the amount of vesicle protein used. Sensitivity to osmolarity was consistent with intravesicular COL accumulation. The ATP-dependent colchicine uptake was sensitive to temperature in a manner consistent with a protein-mediated transport process with activation energy of 7.3 kcal/mol. Time-dependent COL uptake by proteoliposomes in the presence of ATP was consistent with a single compartment model with an apparent rate constant of 0.21 +/- 0.02 min-1. Kinetic studies indicated a saturable behavior with respect to ATP (Km 2.3 +/- 0.7 mM) and colchicine (Km 4.3 +/- 0.2 microM). LTC4 was found to be a competitive inhibitor of COL transport (Kis 16.4 microM). Since DNP-SG ATPase is present in many tissues, it may play an important role in determining colchicine accumulation in cells. Increased LTC4 would tend to increase cellular COL accumulation. 相似文献
23.
This paper describes the use of the bromodeoxyuridine/propidium iodide method to assess the effects of bioactive and cytotoxic agents on the kinetic characteristics of acute myelogenous leukemia cells. By careful selection of gates, the following parameters can be measured simultaneously using only 50,000 cells: the proportion of cells in S-phase, the distribution of cells within the S-phase compartment, the relative rate of DNA synthesis, the relative distribution of S-phase times, the proportion of S0 cells, and the proportion of cells in G1 and G2/M. This method was used to demonstrate that while retinoic acid, alpha-interferon, and cytosine arabinoside may all "inhibit" DNA synthesis, the actual effects of these agents differ. Retinoic acid appears to arrest cells in G1 without affecting the rate of DNA synthesis, while alpha-interferon and cytosine arabinoside "inhibit" DNA synthesis by reducing the rate of synthesis per se. 相似文献
24.
P. M. Parikh S. H. Advani J. S. Nadkarni S. Kulkarni G. Kapoor P. S. R. K. Sastry M. Anand T. K. Saikia R. Gopal 《Cancer investigation》1997,15(4):326-328
Hepatic veno-occlusive disease (VOD) is the second most common cause of death after autologous bone marrow transplantation (ABMT). A patient with multiple myeloma undergoing ABMT developed classic features of hepatic VOD. He responded to treatment with pentoxiphyllin. Serum tumor necrosis factor (TNF) levels showed remarkable correlation with the severity of VOD and response to therapy. 相似文献
25.
G. K. Maheshwari H. A. Baboo Usha Gopal M. K. Wadhwa 《Indian journal of otolaryngology and head and neck surgery》2004,56(2):138-141
Sarcomas constitute fewer than 1% of the head and neck cancers. They represent less than 1% of laryngeal cancers. Primary
rhabdomyosarcoma of the larynx is an extremely rare malignancy. The available literature on this medical oddity is in the
form of isolated case reports only. The purpose of this article is to add another case of primary rhabdomyosarcoma of a rare
site, the larynx, of which only 36 cases have so far been reported in the world literature. The present patient, an eighteen-year-old
boy is only the third case being reported from India among all reported cases of rhabdomyosarcoma of the larynx in the world
literature. 相似文献
26.
I. E. Ezeagu A. G. Gopal Krishna S. Khatoon L. R. Gowda 《Ecology of food and nutrition》2004,43(4):295-305
Analysis showed the seeds of Adenanthera pavonina contained appreciable amounts of proteins (29.44g/100g), crude fat (17.99g/100g), and minerals, comparable to commonly consumed staples. Total sugar was low (8.2g/100g) while starch (41.95g/100g) constitutes the major carbohydrates. Low levels of antinutrients were reported and methionine and cystine were the most deficient amino acids. Linoleic and oleic acids make up 70.7 percent of the total fatty acids. Free fatty acid levels were relatively high but peroxide and saponification values of 29.6mEqkg-1 and 164.1mgKOHg-1respectively point to a resemblance to oils processed for food. It was concluded that A. pavonina seeds represent a potential source of oil and protein that could alleviate shortages. 相似文献
27.
Brain undergoes neurodegeneration when excess free radicals overwhelm antioxidative defense systems during senescence, head trauma and/or neurotoxic insults. A site-specific accumulation of ferrous citrate-iron complexes in the substantia nigra dopaminergic neurons could lead to exaggerated dopamine turnover, dopamine auto-oxidation, free radical generation, and oxidant stress. Eventually, this iron-catalyzed dopamine auto-oxidation results in the accumulation of neuromelanin, a progressive loss of nigral neurons, and the development of Parkinson's disease when brain dopamine depletion is greater than 80%. Emerging evidence indicates that free radicals such as hydroxyl radicals ((.-)OH) and nitric oxide ((.-)NO) may play opposite role in cell and animal models of parkinsonism. (.-)OH is a cytotoxic oxidant whereas oNO is an atypical neuroprotective antioxidant. (.-)NO and S-nitrosoglutathione (GSNO) protect nigral neurons against oxidative stress caused by 1-methyl-4-phenylpyridinium (MPP(+)), dopamine, ferrous citrate, hemoglobin, sodium nitroprusside and peroxynitrite. MPP(+), the toxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), increases the nigral uptake of iron complexes and dopamine overflow leading to the generation of (.-)OH, protein oxidation, lipid peroxidation, and associated retrograde degeneration. In addition to GSNO, MPP(+)-induced oxidative neurotoxicity can be prevented by antioxidants including selegiline, 7-nitroindazole, 17beta-estradiol, melatonin, alpha-phenyl-tert-butylnitrone and U78517F. Similar to selegiline, 7-nitroindazole is a MAO-B inhibitor, which blocks the bio-activation of MPTP and oxidative stress. Freshly prepared but not light exposed, (.-)NO-exhausted GSNO is about 100 times more potent than the classic antioxidant glutathione. Via S-nitrosylation, GSNO also inhibits proteolysis and cytotoxicity caused by caspases and HIV-1 protease. Furthermore, in addition to protection against serum deprivation stress, the induction of neuronal NOS1 in human cells increases tolerance to MPP(+)-induced neuro-toxicity since newly synthesized (.-)NO prevents apoptosis possibly through up-regulation of bcl-2 and down regulation of p66(shc). In conclusion, reactive oxygen species are unavoidable by-products of iron-catalyzed dopamine auto-oxidation, which can initiate lipid peroxidation, protein oxidation, DNA damage, and nigral loss, all of which can be prevented by endogenous and exogenous (.-)NO. Natural and man-made antioxidants can be employed as part of preventative or neuroprotective treatments in Parkinson's disease and perhaps dementia complexes as well. For achieving neuroprotection and neuro-rescue in early clinical parkinsonian stages, a cocktail therapy of multiple neuroprotective agents may be more effective than the current treatment with extremely high doses of a single antioxidative agent. 相似文献
28.
Purpose:To assess the level of knowledge, attitude, and clinical practice of glaucoma among optometry students and optometry practitioners with different years of clinical experience and academic background.Methods:A survey with 20 questions on knowledge, attitude, and practice (KAP) of glaucoma was prepared and self-administered to optometry students and optometry practitioners practicing in an eye hospital/clinic/optical with varied years of clinical experience and education qualification.Results:Among the 558 participants, 57% were optometry practitioners and 43% were students. The knowledge scores among optometry practitioners increased significantly with an increase in the years of clinical experience (P < 0.001). Participants with master’s degrees scored higher than participants with bachelor’s degrees (P = 0.12). There was no statistically significant difference in knowledge scores based on the type of clinical practice - hospital, private practice, or optical (P = 0.39). Practicing optometrists who performed slit-lamp examination, gonioscopy, IOP measurements, and disc evaluation for the detection of glaucoma had significantly higher knowledge scores than those who did not perform these tests in their practice (P < 0.05). A positive attitude toward glaucoma learning through workshops and hands-on training was reported by optometrists and students.Conclusion:Knowledge about glaucoma was good among optometrists and optometry students and was better among those who handled the diagnostics. All the optometrists had a positive attitude toward enhancing their practice through proper training. 相似文献
29.
Neha Shree Monica Gandhi Abhishek Dave Umang Mathur 《Indian journal of ophthalmology》2022,70(4):1239
Purpose:To carry out a prospective study to analyze the incidence and various preoperative, intraoperative, and postoperative risk factors for the development of PPKG.Methods:A total of 207 patients were analyzed prospectively, who were operated for penetrating keratoplasty (PK) in a tertiary eye care hospital between the time period of August 1, 2017 and February 28, 2018 and were followed up till the sixth month. Each patient was analyzed at every visit to determine the factors responsible for post-keratoplasty glaucoma.Results:Out of 207 eyes, post-PK glaucoma developed in 84 cases, which yielded an incidence of 41%. Incidence of PPKG (Post PK glaucoma) in various conditions was as follows: in repeat PK 62%, in perforated corneal ulcer 33%, in nonperforated corneal ulcer 29%, in corneal scar including adherent leukoma 37.2%, and in pseudophakic bullous keratopathy and aphakic bullous keratopathy, 14% and 80%, respectively. In age- and sex-adjusted multivariate analysis, the significant risk factors were age (P-value- 0.006), presence of PAS (P-value 0.001), and fellow eye glaucoma (P-value 0.04). Aphakia and combined surgery were not found to be significantConclusion:Our study recommends a meticulous examination of the fellow eye to assess the presence of glaucoma as it can increase the suspicion of glaucoma in the eye to be operated. The presence of PAS and age are important risk factors for developing PPKG. The risk of developing PPKG increases exponentially as the number of risk factors increases, but the presence of more than three risk factors does not add to the development of PPKG. 相似文献
30.