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Atul Kumar

Publications and source records attributed to Atul Kumar.

At least 19 recordsLinked to original sources
PubMed2006

Comparative evaluation of vitrectomy and dye-enhanced ILM peel with grid laser in diffuse diabetic macular edema.

BACKGROUND: The purpose of this study is to compare the effectiveness of pars plana vitrectomy (PPV) and dye-enhanced peeling of the internal limiting membrane (ILM) with modified grid laser photocoagulation in patients with diffuse diabetic macular edema and to determine if any correlation exists between improvement in visual acuity (functional improvement) and reduction in foveal thickness and macular volume (anatomical improvement). DESIGN: This is a randomized, prospective, comparative, interventional study. METHOD: In this study 24 eyes of 24 patients with metabolically stable diabetes and with diffuse diabetic macular edema were evaluated. The patients were randomized to either pars plana vitrectomy with removal of ILM which was done in 12 eyes (ILM group) and modified grid laser photocoagulation carried out in the remaining 12 eyes (laser group). Main outcome measures were (1) the postoperative visual acuity in the form of ETDRS log MAR values, (2) foveal thickness and (3) macular volume as measured by optical coherence tomography. The correlation between improvement in visual acuity and the reduction of foveal thickness and macular volume in both the groups were also evaluated. The results were all subjected to statistical analysis. RESULTS: The ETDRS log MAR visual acuity difference between the two groups at the end of 6 months was not clinically significant (P = 0.525). However, foveal thickness and macular volume decreased significantly more in the ILM group compared to the laser group (P = 0.001, P < 0.001, Mann Whitney U test). There was no correlation between the improvement in visual acuity and the reduction of foveal thickness (r = -0.158, P = 0.6) (ILM group), r = -0.155, P = 0.7) (laser group) in both groups. CONCLUSIONS: PPV with ILM peeling was shown to be beneficial by inducing a statistically significant reduction of macular thickness and macular volume. Visual acuity also demonstrated a trend towards improvement in both the ILM peel group and the grid laser group; however, the comparative VA outcome analysis between the two groups was not significantly different. Besides, there was also no correlation between the reductions of foveal thickness and macular volume with the improvement in visual acuity in either of the groups.

Adult↗
PubMed2006

Determination of constituents of Telazol--tiletamine and zolazepam by a gas chromatography/mass spectrometry-based method.

Tiletamine and zolazepam injection (Telazol) is used in veterinary surgical practice to induce short-term anesthesia and also to immobilize wild animals. The present work describes a sensitive method to measure tiletamine and zolazepam concentrations in plasma by means of GC/EI-MS on a 5% phenyl/95% methylpolysiloxane column. A simple liquid extraction procedure with ethyl acetate was used to isolate the two compounds and the same were separated and analyzed by GC/MS without derivatization. A formal validation of the assay demonstrated good accuracy and precision for both tiletamine (98-100.8%; C.V.total < 6.7%) and zolazepam (98.3-103.4; C.V.total < 13.2%). With 500 microl of plasma, the limits of quantification for both tiletamine and zolazepam were found to be 10 ng/ml. Both compounds were stable after three freeze-thaw cycles. The assay was used to analyze plasma samples collected from a pig after intramuscular administration of 10 mg/kg of Telazol. The plasma concentration-time profile of tiletamine and zolazepam from this representative pig is also provided.

Animals↗
PubMed2006

Comparison of NMP22 BladderChek test and urine cytology for the detection of recurrent bladder cancer.

OBJECTIVE: To assess the clinical performance of the NMP22 BladderChek test, which is a qualitative test, and to compare it with voided urine cytology for the detection of recurrent bladder cancer. We also evaluated whether cystoscopy can be omitted from the surveillance protocol by combining the two tests. METHODS: A total of 131 patients with a history of superficial transitional cell carcinoma of the bladder provided urine samples before a cystoscopic examination. Urine samples were assayed for the presence of NMP22 using the NMP22 BladderChek test and cytology was performed by a cytopathologist. Selected patients underwent a biopsy, with appropriate additional therapy. Results of the two tests were compared with that the results of cystoscopy, which was retained as the gold standard. For positive biopsies, the results of the NMP22 test and cytology were also correlated with the tumor stage and grade. RESULTS: Of the 46 recurrences detected by cystoscopy, the NMP22 test was positive in 39 cases and cytology in 19 cases. The sensitivity of the NMP22 test was 85%, which was significantly greater than that of cytology (41%). In particular, for low-risk tumors it was eight times more sensitive than cytology. The specificities of the NMP22 test and cytology were 77 and 96%, respectively. Combining the two tests increased overall sensitivity to 91%. However, 9% of the tumors were still not detected. CONCLUSION: The NMP22 BladderChek test is an in vitro qualitative test that is easily available and cheap; it can be performed by a urologist in the office and results can be interpreted within 30 min. The NMP22 test is superior to cytology for all grades and stages in the detection of recurrence in patients with a history of superficial bladder cancer. Our study indicates that the NMP22 test can be used as a substitute for urine cytology. The NMP22 test cannot replace cystoscopy, but it can be used as an adjunct to cystoscopy in the surveillance protocol for patients with superficial bladder cancer.

Adult↗
PubMed2006

Novel substituted naphthalen-1-yl-methanone derivatives as anti-hyperglycemic agents.

A series of aminoalkoxy phenyl-substituted naphthalene-1-yl-methanone was synthesized and tested for its anti-hyperglycemic activity in SLM and STZ-S rat models. Some compounds (3b, 4c and 4h) of the series were showing significant anti-hyperglycemic activity in male Sprague-Dawley rats in sucrose-loaded model (SLM) as well as in streptozotocin-induced model (STZ-S). Active compounds were also evaluated for relative binding affinity against glucagon receptor.

Animals↗
PubMed2006

Second- and third-line treatments in non-small cell lung cancer.

Slow but steady progress has been made in the treatment of advanced non-small cell lung cancer. For first-line therapy, multiple chemotherapy combination therapies can extend survival and improve quality of life. And recently, for the first time ever, a noncytotoxic agent, the antivascular endothelial growth factor antibody bevacizumab, has been shown to improve survival when added to chemotherapy. Striking improvements have also been made in second-line treatment. In August 2004, only one agent was US Food and Drug Administration (FDA) approved in this setting, docetaxel, but by the beginning of 2005, two more were available, pemetrexed and erlotinib. All three of these drugs can significantly benefit patients, with 1-year survival in excess of 30%. Choosing between the three agents can be challenging, and this review focuses on the toxicity differences and predictors of response that can help guide this decision. Docetaxel and pemetrexed, both traditional intravenous cytotoxins, are excellent options for patients who have shown some response to first-line chemotherapy, but at this time, no other means exist to determine likelihood of response. When choosing between the two, pemetrexed causes significantly less neutropenia than does docetaxel, at least on the standard every-3-week regimen. With erlotinib, an oral epidermal growth factor receptor (EGFR) inhibitor, there are factors that can predict for response, including little or no smoking history, and adenocarcinoma histology. Therefore, patients who fit these characteristics are good candidates for second-line erlotinib. However, the relationship between response to erlotinib and improved survival remains unclear, and several laboratory analyses that may help further, such as evaluation of EGFR gene copy number, are still under development. Although erlotinib is the only FDA-approved option currently available for third-line therapy, many patients with good performance status may benefit from third-line therapy and beyond. In addition to the approved second-line options, other single-agent chemotherapies to consider for treatment beyond second-line are gemcitabine, irinotecan, and oral topotecan. Many new drugs, including bevacizumab, ZD6474 (AstraZeneca, Wilmington, DE), sorafenib, cetuximab, paclitaxel poliglumex, epothilones, and others, alone or in combination with traditional agents, are currently undergoing investigation and hold great promise.

Antineoplastic Agents↗
PubMed2006

Comparative evaluation of oral fluorescein angiography using the confocal scanning laser ophthalmoscope and digital fundus camera with intravenous fluorescein angiography using the digital fundus camera.

BACKGROUND: To study the efficacy of oral fluorescein angiography (FA) with confocal scanning laser ophthalmoscope (CSLO). METHODS: Ten patients each of choroidal neovascular membrane, central serous retinopathy, diabetic retinopathy and five normal subjects were evaluated with group 1 - intravenous FA using digital fundus camera (DFC); group 2 - oral FA using DFC; and group 3 - oral FA using CSLO. RESULTS: Third-order branch vessels were identified in 85.7% eyes in group 3 versus 51.4% in group 2 (P = 0.004), image quality was comparable to intravenous FA in 77.1% in group 3 versus 48.5% in group 2 (P = 0.02) and margin delineation was better in 80% eyes in group 3 versus 35% in group 2 (P = 0.01). The foveal avascular zone was clear and intact in 54.2% eyes in group 3 versus 37.1% in group 2 (P = 0.14) and 57.1% in group 1 (P = 0.8). CONCLUSION: Oral FA using CSLO is superior to oral FA using DFC and comparable to intravenous FA using DFC in terms of image quality, branch retinal vessel identification and margin delineation.

Administration, Oral↗
PubMed2005

Vogt-Koyanagi-Harada syndrome with intracranial meningioma: an as yet unreported association.

CASE REPORT: We document a previously unreported association of Vogt-Koyanagi-Harada (VKH) syndrome with intracranial meningioma. A female patient with diminished vision, exudative retinal detachment, and headache was diagnosed with VKH syndrome, more precisely a Harada form of disease with intracranial meningioma, on the basis of exudative retinal detachment, typical fundus fluorescein findings, and magnetic resonance imaging. With intravenous steroid therapy, visual acuity improved and the detachment settled within a week. At 3 months, the detachment recurred but improved after retreatment. At 1 year, the tumour was unchanged in size. COMMENTS: VKH syndrome may be associated with intracranial meningioma that may affect the patient's overall morbidity or mortality.

Adult↗
PubMed2005

Cleavage of oximes using a solid supported hypervalent organoiodine reagent.

A facile and efficient oxidative cleavage of oximes to form carbonyl compounds is reported using phenyl iodonium (III) diacetate (PIDA) and polymer supported polydiacetoxyiodostyrene. Regeneration of carbonyl compounds from corresponding oximes is an important reaction, since oxime derivatives constitute one of the primary methods for purification and characterization of carbonyl compounds. This process overcomes many of the disadvantages associated with other oxidative methods such as long reaction times, difficulties in isolation of products and formation of over oxidized products.

Acetates↗
PubMed2005

Visual outcome and electron microscopic features of indocyanine green-assisted internal limiting membrane peeling from macular hole of various aetiologies.

PURPOSE: To describe the visual outcome of internal limiting membrane (ILM) peeling for macular hole of various aetiologies and ultrastructural features of the ILM. MATERIALS AND METHODS: The study was conducted on 40 eyes of 38 patients. Thirty eyes with full thickness macular hole were treated with vitrectomy and removal of ILM. Ten eyes with retinal detachment served as negative controls and these patients underwent vitrectomy and ILM removal. The surgical specimens were examined by transmission electron microscopy. RESULTS: The anatomical success rate of the first operation was 90% in idiopathic and myopic groups, whereas it was 100% in traumatic macular hole group. Visual improvement of (3) two lines was noted in 80% of the cases. Electron microscopy revealed the presence of ILM in all surgical specimens. Proliferation of astrocytes and synthesis of new collagen along the inner surface of ILM was noted in the surgical specimens. CONCLUSION: Our findings suggest that the ILM removal helps in closure of the macular hole and retinal reattachment. Vitrectomy with ILM peeling is a reasonable surgical approach to treat macular holes of idiopathic, myopic and traumatic aetiology.

Adolescent↗
PubMed2004

Requirement of c-myb in T cell development and in mature T cell function.

Previous reports have suggested that the protooncogene c-myb participates in T cell development in the thymus and mature T cell proliferation. We have generated two T cell-specific c-myb knockout mouse models, myb/LckCre and myb/CD4Cre. We have demonstrated that c-myb is required for the development of thymocytes at the DN3 stage, for survival and proliferation of double-positive thymocytes, for differentiation of single-positive CD4 and CD8 T cells, and for the proliferative responses of mature T cells. In addition, our data show that c-myb is directly involved in the formation of double-positive CD4+CD8+CD25+, CD4+CD25+, and CD8+CD25+ T cells, developmental processes that may imply a role for c-myb in autoimmune dysfunction.

Animals↗
PubMed2004

Appraisal of four novel approaches to the prevention and treatment of sepsis.

PURPOSE: Four novel approaches to the management of sepsis are discussed. SUMMARY: Drotrecogin alfa (activated) has FDA-approved labeling for use in the treatment of severe sepsis. Risk of bleeding and identification of the most suitable patients have been the major issues related to use of this drug. Tight glycemic control and early goal-directed therapy (EGDT) are promising supportive strategies. Both have challenged existing views regarding safe glucose levels and the usefulness of increased oxygen delivery in sepsis. The routine maintenance of euglycemia is resource intensive, however, and benefits during treatment of sepsis are unclear. Very early initiation of measures to optimize hemodynamic variables and the ability to identify patients with cryptic shock appear to be key reasons for successful EGDT. The use of corticosteroids for septic shock has been extensively researched and has provoked controversy. Selection of patients likely to benefit on the basis of relative adrenal insufficiency and prolonged treatment may account for recently observed positive results. A model for combining the four strategies is proposed. CONCLUSION: Novel strategies for treating sepsis include drotrecogin alfa (activated), tight glycemic control, EGDT, and low-dose corticosteroids.

Adrenal Cortex Hormones↗
PubMed2004

Diaryl naphthyl methanes a novel class of anti-implantation agents.

Diaryl naphthyl methanes and the corresponding 1, 2, 3, 4- and 5, 6, 7, 8-tetrahydro naphthyl methane derivatives have been synthesized as novel estrogen receptor binding ligands. The secondary and tertiary amino alkoxy derivatives of diaryl naphthyl and tetrahydro naphthyl methane interact with the estrogen receptor to elicit promising estrogenic, antiestrogenic and implantation inhibition activities in rats. The most active compounds in this series are 7, 9 and 20, cent percent active in preventing implantation in rats at 2.5 mgkg(-1) dose.

Animals↗
PubMed2004

A simple technique to reduce fluid intravasation during endometrial resection.

The rate of fluid intravasation may abruptly and alarmingly increase during endometrial resection. Left unchecked, this may lead to complications of fluid overload. In 20 patients, temporary cessation of surgery in the form of a 10-minute glycine-free interval reduced the rate of fluid intravasation by 38.75% to 85.81% (mean 67.09%) in the later part of surgery. This was possibly due to hemostatic sealing of open blood vessels which prevented further intravasation of distending medium into systemic circulation.

Absorption↗
PubMed2004

Transpupillary thermotherapy for idiopathic subfoveal choroidal neovascularization.

PURPOSE: To assess the efficacy of transpupillary thermotherapy (TTT) for the management of idiopathic subfoveal choroidal neovascularization (CNV). METHODS: This was a prospective, non-controlled, clinical case trial involving 21 eyes of 21 patients with a mean age of 36 years. All 21 eyes had idiopathic subfoveal CNV and were subjected to diode laser TTT. Laser beam size ranged from 1.2 mm to 3.0 mm and power settings ranged between 300 mW and 600 mW. The end-point was an area of no visible colour change. Pre- and post-laser evaluations of ETDRS visual acuity, contrast sensitivity, slit-lamp biomicroscopy and fluorescein angiography were carried out. RESULTS: The nine predominantly occult and 12 predominantly classic subfoveal membranes were followed-up for a mean of 5.1 months after TTT. Overall, 17 eyes (81%) showed improvement or stabilization in ETDRS visual acuity. Contrast sensitivity improved in 17 eyes (81%). Reading speed improved in 15 eyes (71%). Retreatment was needed in three eyes (14%). CONCLUSION: Transpupillary thermotherapy treatment is a potential strategy for treating idiopathic subfoveal CNV in both its classic and occult forms.

Adult↗