51
|
Lassri H, Hlil E, Prasad S, Krishnan R. Magnetic and electronic properties of nanocrystalline Gd3Fe5O12 garnet. J SOLID STATE CHEM 2011. [DOI: 10.1016/j.jssc.2011.09.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
|
52
|
Mehta P, Kalyanpur T, Narsinghpura K, Krishnan R, Raja D, Yadav M, Cherian M. Outcomes of Endovascular Coiling in Patients with Intracranial Aneurysms Presenting with Poor Clinical and SAH Grade. Neuroradiol J 2011; 24:669-76. [DOI: 10.1177/197140091102400502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 01/23/2011] [Indexed: 11/16/2022] Open
Abstract
Although the treatment of intracranial aneurysms has made significant advances, prediction of outcomes in poor grades has always been difficult. We present our findings of patients in poor clinical and SAH grade treated with endovascular coiling. We aimed to evaluate the clinical outcomes in patients presenting with poorer neurological and SAH grades treated by endovascular techniques. Of 190 patients who presented with SAH over a period of nine years, 34 were of poorer clinical grade (Hunt & Hess Grades 4 and 5), of whom 30 presented with H&H grade 4 and four with grade 5. 44.1% of the 34 patients belonged to Fischer grade 4. We assessed the technical success and final outcomes based on the Glasgow outcome scale. Of the 30 patients with grade 4, 81.4% had a good outcome. Two out of four patients with grade 5 had a poor outcome. 82.5% of the patients with Fischer grade 4 had a good outcome. None of the poor outcomes were procedure-related. Endovascular treatment with its higher rates of technical success, lower complication rates and better outcomes should be recommended as the treatment of choice in patients with intracranial aneurysms even in patients with poorer clinical and SAH grades.
Collapse
|
53
|
Pradhan PK, Preethi B, Ashok K, Krishnan R, Sahai AK. Modoki, Indian Ocean Dipole, and western North Pacific typhoons: Possible implications for extreme events. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd015666] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
54
|
Krishnan R, Ratnadurai S, Subramanian D, Chakravarthy VS, Rengaswamy M. Modeling the role of basal ganglia in saccade generation: is the indirect pathway the explorer? Neural Netw 2011; 24:801-13. [PMID: 21726978 DOI: 10.1016/j.neunet.2011.06.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 04/25/2011] [Accepted: 06/02/2011] [Indexed: 11/28/2022]
Abstract
We model the role played by the Basal Ganglia (BG) in the generation of voluntary saccadic eye movements. The BG model explicitly represents key nuclei like the striatum (caudate), Substantia Nigra pars reticulata (SNr) and compata (SNc), the Subthalamic Nucleus (STN), the two pallidal nuclei and Superior Colliculus. The model is cast within the Reinforcement Learning (RL) framework, with the dopamine representing the temporal difference error, the striatum serving as the critic, and the indirect pathway playing the role of the explorer. Performance of the model is evaluated on a set of tasks such as feature and conjunction searches, directional selectivity and a successive saccade task. Behavioral phenomena such as independence of search time on number of distractors in feature search and linear increase in search time with number of distractors in conjunction search are observed. It is also seen that saccadic reaction times are longer and search efficiency is impaired on diminished BG contribution, which corroborates with reported data obtained from Parkinson's Disease (PD) patients.
Collapse
|
55
|
Trikha S, Turnbull A, Srikantha N, Krishnan R, Tappin A. Anterior keratouveitis secondary to Hydroa vaccineforme: a role for ophthalmic slit-lamp examination in this condition? BMJ Case Rep 2011; 2011:2011/apr12_1/bcr0920103309. [PMID: 22701003 DOI: 10.1136/bcr.09.2010.3309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The authors report the case of an 8-year-old girl of Caucasian origin who attended the Emergency Eye Clinic with a 3-week history of a red, light sensitive left eye during the month of April. Her Snellen visual acuities were 6/5 right and 6/9 left. Examination revealed perilimbal injection and anterior chamber inflammation in the left eye consistent with an anterior uveitis. Inferior stromal haze and fine keratic precipitates were noted in the left cornea. Intraocular pressures were normal, with no vitritis and healthy looking discs, maculae and peripheral retina. Systemic examination revealed a papular rash over the face consistent with previously diagnosed Hydroa vaccineforme. With intensive topical steroids the inflammation gradually resolved.
Collapse
|
56
|
Xiong GL, Jiang W, Clare RM, Shaw LK, Smith PK, O'Connor CM, Ranga K, Krishnan R, Kristin Newby L. Safety of selective serotonin reuptake inhibitor use prior to coronary artery bypass grafting. Clin Cardiol 2010; 33:E94-8. [PMID: 20552618 DOI: 10.1002/clc.20621] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Selective serotonin reuptake inhibitors (SSRIs) have been shown to increase bleeding risks. This study examined the association of perioperative coronary artery bypass grafting (CABG) bleeding risks and SSRI use prior to CABG. HYPOTHESIS SSRI may be associated with increased bleeding risks after CABG resulting in elevated reoperation rates due to bleeding complications. METHODS Patients who underwent CABG between 1999 and 2003 (n = 4794) were identified in a tertiary medical center. SSRI use (n = 246) was determined using inpatient pharmacy records. Outcomes included primary end point of reoperation due to bleeding complications and other secondary measures. Multivariate regression models were constructed to adjust for baseline differences between SSRI and control groups. RESULTS Reoperation due to bleeding complications among SSRI users was not significantly different (odds ratio [OR]: 1.14 (0.52-2.47); P = 0.75) compared to the control group. Other secondary outcomes and 30-day mortality (2.0% in SSRI vs 2.1% in control group; P = 0.92) between the 2 groups were similar. However, the adjusted total volume of postoperative red blood cell (RBC) units transfused was higher in the SSRI group. CONCLUSION We conclude that there is no compelling evidence to limit the use of SSRIs among patients with coronary artery disease who undergo CABG given the current evidence. Further research may be needed on individual SSRI medications.
Collapse
|
57
|
Patil B, Chavan S, Pethe S, Krishnan R, Bhoraskar V, Dhole S. Simulation of e–γ–n targets by FLUKA and measurement of neutron flux at various angles for accelerator based neutron source. ANN NUCL ENERGY 2010. [DOI: 10.1016/j.anucene.2010.05.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
58
|
Manikandan E, Moodley MK, Sinha Ray S, Panigrahi BK, Krishnan R, Padhy N, Nair KGM, Tyagi AK. Zinc oxide epitaxial thin film deposited over carbon on various substrate by pulsed laser deposition technique. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:5602-5611. [PMID: 21133080 DOI: 10.1166/jnn.2010.2478] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Zinc Oxide (ZnO) is a promising candidate material for optical and electronic devices due to its direct wide band gap (3.37 eV) and high exciton binding energy (60 meV). For applications in various fields such as light emitting diode (LED) and laser diodes, growth of p-type ZnO is a prerequisite. ZnO is an intrinsically n-type semiconductor. In this paper we report on the synthesis of Zinc Oxide-Carbon (ZnO:C) thin films using pulsed laser deposition technique (PLD). The deposition parameters were optimized to obtain high quality epitaxial ZnO films over a carbon layer. The structural and optical properties were studied by glazing index X-ray diffraction (GIXRD), photoluminescence (PL), optical absorption (OA), and Raman spectroscopy. Rutherford backscattering spectroscopy (RBS), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and atomic force microscopy (AFM) were employed to determine the composition and surface morphology of these thin films. The GIXRD pattern of the synthesized films exhibited hexagonal wurtzite crystal structure with a preferred (002) orientation. PL spectroscopy results showed that the emission intensity was maximum at -380 nm at a deposition temperature of 573 K. In the Raman spectra, the E2 phonon frequency around at 438 cm(-1) is a characteristic peak of the wurtzite lattice and could be seen in all samples. Furthermore, the optical direct band gap of ZnO films was found to be in the visible region. The growth of the epitaxial layer is discussed in the light of carbon atoms from the buffer layer. Our work demonstrates that the carbon is a novel dopant in the group of doped ZnO semiconductor materials. The introduction of carbon impurities enhanced the visible emission of red-green luminescence. It is concluded that the carbon impurities promote the zinc related native defect in ZnO.
Collapse
|
59
|
Krishnan R, Liu Y, Gaire C, Chen L, Wang GC, Lu TM. Texture evolution of vertically aligned biaxial tungsten nanorods using RHEED surface pole figure technique. NANOTECHNOLOGY 2010; 21:325704. [PMID: 20639581 DOI: 10.1088/0957-4484/21/32/325704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Vertically aligned biaxial tungsten nanorods with cubic A15 crystal structure were deposited by DC magnetron sputtering on native oxide covered Si(100) substrates with glancing angle flux incidence (theta approximately 85 degrees) and a two-step substrate rotation mode at room temperature. These vertical nanorods were grown to different thicknesses (10, 25, 50 and 100 nm) and analyzed for biaxial texture evolution using a highly surface sensitive reflection high-energy electron diffraction (RHEED) pole figure technique. The initial polycrystalline film begins to show the inception of biaxial texture with a fiber background between 10 and 25 nm. Biaxial texture development is eventually completed between 50 and 100 nm thicknesses of the film. The out-of-plane crystallographic direction is [002] and the in-plane texture is selected so as to obtain maximum capture area. In a comparison with 100 nm thick inclined tungsten nanorods deposited at 85 degrees without substrate rotation, it is found that the selection of in-plane texture does not maintain maximum in-plane capture area. This anomalous behavior is observed when the [002] texture axis is tilted approximately 17 degrees from the substrate normal in the direction towards the glancing incident flux.
Collapse
|
60
|
Abstract
Leiomyosarcoma of the anal canal is an uncommon neoplasm of the gastrointestinal tract. We report a 45-year-old lady with anal canal leiomyosarcoma. In view of its rarity, we report its presentation and management. In the setting of a recurrent tumor with high-grade histological appearance, local excision would be deemed unsafe.
Collapse
|
61
|
Sahoo SC, Venkataramani N, Prasad S, Bohra M, Krishnan R. Pulse laser deposited nanocrystalline cobalt ferrite thin films. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:3112-3117. [PMID: 20358907 DOI: 10.1166/jnn.2010.2173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Cobalt ferrite thin films were pulsed laser deposited on fused quartz substrates at different substrate temperatures and ex-situ annealed at 750 degrees C in air. Grain size of these films was found to be 6-44 nm. Magnetization of these nanocrystalline thin films was found to be dependent on the substrate temperature. Magnetization higher than the cobalt ferrite bulk value was observed in the room temperature deposited film after post deposition annealing at 750 degrees C. This could be explained on the basis of a changed cation distribution in the film caused by quenching during deposition.
Collapse
|
62
|
Bakker AD, Silva VCD, Krishnan R, Bacabac RG, Blaauboer ME, Lin YC, Marcantonio RAC, Cirelli JA, Klein-Nulend J. Tumor necrosis factor alpha and interleukin-1beta modulate calcium and nitric oxide signaling in mechanically stimulated osteocytes. ACTA ACUST UNITED AC 2010; 60:3336-45. [PMID: 19877030 DOI: 10.1002/art.24920] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Inflammatory diseases often coincide with reduced bone mass. Mechanoresponsive osteocytes regulate bone mass by maintaining the balance between bone formation and resorption. Despite its biologic significance, the effect of inflammation on osteocyte mechanoresponsiveness is not understood. To fill this gap, we investigated whether the inflammatory cytokines tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta) modulate the osteocyte response to mechanical loading. METHODS MLO-Y4 osteocytes were incubated with TNFalpha (0.5-30 ng/ml) or IL-1beta (0.1-10 ng/ml) for 30 minutes or 24 hours, or with calcium inhibitors for 30 minutes. Cells were subjected to mechanical loading by pulsatile fluid flow (mean +/- amplitude 0.7 +/- 0.3 Pa, 5 Hz), and the response was quantified by measuring nitric oxide (NO) production using Griess reagent and by measuring intracellular calcium concentration ([Ca(2+)](i)) using Fluo-4/AM. Focal adhesions and filamentous actin (F-actin) were visualized by immunostaining, and apoptosis was quantified by measuring caspase 3/7 activity. Cell-generated tractions were quantified using traction force microscopy, and cytoskeletal stiffness was quantified using optical magnetic twisting cytometry. RESULTS Pulsatile fluid flow increased [Ca(2+)](i) within seconds (in 13% of cells) and NO production within 5 minutes (4.7-fold). TNFalpha and IL-1beta inhibited these responses. Calcium inhibitors decreased pulsatile fluid flow-induced NO production. TNFalpha and IL-1beta affected cytoskeletal stiffness, likely because 24 hours of incubation with TNFalpha and IL-1beta decreased the amount of F-actin. Incubation with IL-1beta for 24 hours stimulated osteocyte apoptosis. CONCLUSION Our results suggest that TNFalpha and IL-1beta inhibit mechanical loading-induced NO production by osteocytes via abrogation of pulsatile fluid flow-stimulated [Ca(2+)](i), and that IL-1beta stimulates osteocyte apoptosis. Since both NO and osteocyte apoptosis affect osteoclasts, these findings provide a mechanism by which inflammatory cytokines might contribute to bone loss and consequently affect bone mass in rheumatoid arthritis.
Collapse
|
63
|
Krishnan R, Parker T, Lee S, Lu TM. The formation of vertically aligned biaxial tungsten nanorods using a novel shadowing growth technique. NANOTECHNOLOGY 2009; 20:465609. [PMID: 19847032 DOI: 10.1088/0957-4484/20/46/465609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biaxially textured tungsten nanorods (A15 crystal structure) have been grown by oblique angle DC magnetron sputtering using a novel rotation mode called 'two-step rotation'. In this mode, the substrate is given a fast rotation through 180 degrees at 90 rpm and this is followed by a rest period of 30 s. These nanorods are vertically aligned and have a [100] texture normal to the substrate along with preferential in-plane texture as shown by x-ray pole figure analysis. In contrast, the tungsten nanorods obtained without substrate rotation are slanted at an angle of approximately 45 degrees and have a [100] texture tilted 16 degrees with respect to the substrate normal. The flux is incident from two diametrically opposite points on the sample at an oblique angle, averaging out the growth into vertical columns that retain the in-plane texture. Scanning electron microscopy shows that the tungsten nanorods have a mixture of {211} and {421} crystal habits; these planes are both minimum surface energy planes for a cubic A15 crystal structure.
Collapse
|
64
|
Vishwakarma V, Josephine J, George RP, Krishnan R, Dash S, Kamruddin M, Kalavathi S, Manoharan N, Tyagi AK, Dayal RK. Antibacterial copper-nickel bilayers and multilayer coatings by pulsed laser deposition on titanium. BIOFOULING 2009; 25:705-710. [PMID: 20183129 DOI: 10.1080/08927010903132183] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biofouling, especially microfouling, is a major concern with the use of titanium (Ti) in the marine environment as a condenser material in cooling water systems. Earlier, copper-nickel (Cu/Ni) alloys were extensively used in marine environments due to their high corrosion and biofouling resistance. However, the choice of condenser material for the new fast breeder reactor in Kalpakkam is Ti to avoid steam side corrosion problems, which may pose a threat to steam generator parts having sodium as the secondary coolant. This study evaluates the surface modification of Ti using nano films of copper (Cu) and nickel (Ni) to utilize the antibacterial property of copper ions in reducing microfouling. The surface modification of Ti was carried out by the deposition of a Cu/Ni bilayer and (Cu/Ni)(10) multilayer films using a pulsed laser deposition technique. Various surface characterization studies revealed that the deposited Cu/Ni films were thin and nanocrystalline in nature. The antibacterial properties were evaluated using total viable count and epifluorescence microscopic techniques. The results showed an apparent decrease in bacterial attachment on multilayered and bilayered Cu/Ni thin films on Ti surfaces. Comparative studies between the two types of films showed a bigger reduction in numbers of microorganisms on the multilayers.
Collapse
|
65
|
Pandey M, Devi N, Ramdas K, Krishnan R, Kumar V. Higher distress relates to poor quality of life in patients with head and neck cancer. Int J Oral Maxillofac Surg 2009; 38:955-9. [DOI: 10.1016/j.ijom.2009.04.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 11/09/2008] [Accepted: 04/02/2009] [Indexed: 11/28/2022]
|
66
|
Krishnan R, Amirthapandian S, Mangamma G, Ramaseshan R, Dash S, Tyagi AK, Jayaram V, Raj B. Implantation induced hardening of nanocrystalline titanium thin films. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:5461-5466. [PMID: 19928244 DOI: 10.1166/jnn.2009.1162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Formation of nanocrystalline TiN at low temperatures was demonstrated by combining Pulsed Laser Deposition (PLD) and ion implantation techniques. The Ti films of nominal thickness approximatly 250 nm were deposited at a substrate temperature of 200 degrees C by ablating a high pure titanium target in UHV conditions using a nanosecond pulsed Nd:YAG laser operating at 1064 nm. These films were implanted with 100 keV N+ ions with fluence ranging from 1.0 x 10(16) ions/cm2 to 1.0 x 10(17) ions/cm2 The structural, compositional and morphological evolutions were tracked using Transmission Electron Microscopy (TEM), Secondary Ion Mass Spectrometry (SIMS) and Atomic Force Microscopy (AFM), respectively. TEM analysis revealed that the as-deposited titanium film is an fcc phase. With increasing ion fluence, its structure becomes amorphous phase before precipitation of nanocrystalline fcc TIN phase. Compositional depth profiles obtained from SIMS have shown the extent of nitrogen concentration gradient in the implantation zone. Both as-deposited and ion implanted films showed much higher hardness as compared to the bulk titanium. AFM studies revealed a gradual increase in surface roughness leading to surface patterning with increase in ion fluence.
Collapse
|
67
|
Krishnan R. Botulinum Toxin as a Neuro-Relearning Drug Tool in Motor Paralytic Disorders. CURRENT DRUG THERAPY 2009. [DOI: 10.2174/157488509788185169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
68
|
Barrero LH, Katz JN, Perry MJ, Krishnan R, Ware JH, Dennerlein JT. Work pattern causes bias in self-reported activity duration: a randomised study of mechanisms and implications for exposure assessment and epidemiology. Occup Environ Med 2009; 66:38-44. [PMID: 18805887 PMCID: PMC3257319 DOI: 10.1136/oem.2007.037291] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Self-reported activity duration is used to estimate cumulative exposures in epidemiological research. OBJECTIVE The effects of work pattern, self-reported task dullness (a measure of cognitive task demand), and heart rate ratio and perceived physical exertion (measures of physical task demands) on error in task duration estimation were investigated. METHODS 24 participants (23-54 years old, 12 males) were randomly assigned to execute three tasks in either a continuous (three periods of 40 continuous minutes, one for each task) or a discontinuous work pattern (40 min tasks each divided into four periods of 4, 8, 12 and 16 min). Heart rate was measured during tasks. After completing the 2 h work session, subjects reported the perceived duration, dullness and physical exertion for each of the three tasks. Multivariate models were fitted to analyse errors and their absolute value to assess the accuracy in task duration estimation and the mediating role of task demands on the observed results. RESULTS Participants overestimated the time spent shelving boxes (up to 38%) and filing journals (up to 9%), and underestimated the time typing articles (up to -22%). Over- and underestimates and absolute errors were greater in the discontinuous work pattern group. Only the self-reported task dullness mediated the differences in task duration estimation accuracy between work patterns. CONCLUSIONS Task-related factors can affect self-reported activity duration. Exposure assessment strategies requiring workers to allocate work time to different tasks could result in biased measures of association depending on the demands of the tasks during which the exposure of interest occurs.
Collapse
|
69
|
Krishnan R, Raghunathan R, Maru GB. Effect of polymeric black tea polyphenols on benzo(a)pyrene [B(a)P]-induced cytochrome P4501A1 and 1A2 in mice. Xenobiotica 2008; 35:671-82. [PMID: 16316927 DOI: 10.1080/00498250500202155] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The chemopreventive activity of green tea polyphenols (GTPs) is, in part, due to modulation of cytochrome P450s (CYPs). To investigate the enzyme modulatory properties of major black tea polyphenols, the effect of decaffeinated black tea extract (DBTE) or polymeric black tea polyphenol (PBP) mix was studied on CYP1A1 and CYP1A2 in mouse tissues. Animals receiving 2.5% DBTE or 1% PBP mix or drinking water (15 days) were challenged with single oral benzo(a)pyrene (B(a)P) (1 mg/mouse) treatment on the 14th day. Liver and lung microsomes isolated after 24 h were analysed for CYP1A1 and CYP1A2, using biochemical substrate(s) and Western blot analysis. Treatment with 2.5% DBTE or 1% PBP mix did not significantly alter the basal activity and level of CYP1A1 and CYP1A2, whereas pretreatment with 2.5% DBTE or 1% PBP mix resulted in a significant decrease in both the activity and the level of B(a)P-induced CYP1A1 and CYP1A2 in liver and lungs. The PBP mix possesses enzyme modulatory properties exhibited by monomeric GTPs.
Collapse
|
70
|
Fedoric B, Krishnan R. T CELLS ACQUIRE HLA-G VIA TROGOCYTOSIS FROM GENETICALLY MODIFIED HUMAN DENDRITIC CELLS DURING ALLOIMMUNE ACTIVATION. Transplantation 2008. [DOI: 10.1097/01.tp.0000332042.85927.35] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
71
|
Krishnan R, Goverdhan S, Lochhead J. Intravitreal pegaptanib in severe proliferative diabetic retinopathy leading to the progression of tractional retinal detachment. Eye (Lond) 2008; 23:1238-9. [PMID: 18551139 DOI: 10.1038/eye.2008.179] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
72
|
Krishna RP, Sistla SC, Smile R, Krishnan R. Sonography: an underutilized diagnostic tool in the assessment of metastatic groin nodes. JOURNAL OF CLINICAL ULTRASOUND : JCU 2008; 36:212-217. [PMID: 17960822 DOI: 10.1002/jcu.20420] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
PURPOSE To assess the diagnostic value of gray-scale sonography in differentiating benign reactive nodes from metastatic nodes in the groin. METHODS Twenty-seven patients with carcinoma of the penis, 3 patients with cutaneous melanoma, and 2 patients with squamous cell carcinoma of the lower extremity with inguinal lymphadenopathy were studied. A total of 122 nodes in the groin were examined sonographically using a 7.5-MHz probe. Sonographic features studied included lymph node size, longitudinal/transverse diameter (L/T) ratio, presence or absence of echogenic hilum, and appearance of the cortex. Pathologic confirmation was obtained via lymph node biopsy in 14 patients and groin dissection in 18 patients. Sonographic features were correlated with final pathology. RESULTS Forty-four of 122 nodes were metastatic and 78 were benign. L/T <2 had a sensitivity of 81% in the diagnosis of metastasis. Absent hilum had a sensitivity of only 68% but a specificity of 95%. An eccentric cortex was also highly specific for malignancy (96%). Presence of any sonographic feature suggestive of metastasis has a high sensitivity (95%) and negative predictive value (96%). The combination of L/T ratio <2 and absent hilum had the highest specificity (97%) combined with a high positive predictive value (93%). CONCLUSION Sonography is useful in the evaluation of groin nodes for metastatic disease. It can help select a suspicious lymph node for cytologic/histologic confirmation.
Collapse
|
73
|
Patel R, Krishnan R, Ramchandani A, Maru G. Polymeric black tea polyphenols inhibit mouse skin chemical carcinogenesis by decreasing cell proliferation. Cell Prolif 2008; 41:532-53. [PMID: 18400024 DOI: 10.1111/j.1365-2184.2008.00528.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVES The aim of this study was to investigate the antitumour promoting effects and possible mechanisms of action of the most abundant polymeric black tea polyphenols (PBPs 1-5) or thearubigins, in vivo. MATERIALS AND METHODS Effect of PBP pre-treatments on 12-O-tetradecanoylphorbol-13-acetate (TPA) promoted skin papillomas was studied in 7,12-dimethylbenz(a)anthracene initiated mice over 40 weeks. Cell proliferation and apoptosis, in epidermis of the skin, were measured using appropriate immunohistochemical staining. Mitogen-activated protein kinase signalling studies were conducted with Western blot analysis at 10, 20, 30 and 40 weeks of promotion. RESULTS Pre-treatments with PBP fractions differentially altered latency, multiplicity and incidence of skin papillomas as compared to TPA treatments thereby exhibiting antipromoting effects. Most PBP fractions decreased TPA-induced cell proliferation by decreasing activation of signalling kinases (c-Jun N-terminal protein kinase, extracellular signal-regulated protein kinase, p38 protein kinase and Akt), transcription factors (activator protein-1 and nuclear factor kappa B) and inflammatory protein (cyclooxygenase 2). TPA-induced epidermal cell apoptosis was also decreased by pre-treatment with most PBP fractions. Higher levels of p53 and p21 in skin cells pre-treated with PBP fractions followed by TPA treatment as compared to only TPA-treated animals suggested possible activation of a cell cycle checkpoint. CONCLUSIONS PBP-2 was observed to be the most potent polymeric polyphenol fraction and PBP-4 and PBP-5 showed only marginal activity, whereas PBP-1 and PBP-3 displayed intermediate efficacies. In conclusion, the protective effects of PBP fractions could be attributed to inhibition of TPA-induced cellular proliferation.
Collapse
|
74
|
Krishnan R, Cella D, Leonardi C, Papp K, Gottlieb AB, Dunn M, Chiou CF, Patel V, Jahreis A. Effects of etanercept therapy on fatigue and symptoms of depression in subjects treated for moderate to severe plaque psoriasis for up to 96 weeks. Br J Dermatol 2007; 157:1275-7. [PMID: 17916204 DOI: 10.1111/j.1365-2133.2007.08205.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
75
|
Krishnan R, Izadi S, Morton CE, Marsh IB. Use of Frost sutures in an orbital trauma patient with extensive conjunctival oedema and pseudoproptosis. Int J Oral Maxillofac Surg 2007; 36:649-51. [PMID: 17391921 DOI: 10.1016/j.ijom.2007.02.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 12/07/2006] [Accepted: 02/02/2007] [Indexed: 11/17/2022]
Abstract
Frost sutures are temporary suspension sutures conventionally used in oculoplastics. The case is presented here of a patient with multiple orbital fractures who developed worsening conjunctival chemosis and pseudoproptosis. This patient was managed successfully with Frost sutures. To the best of the authors' knowledge, there is no documented use of Frost sutures in this type of case. It is emphasized that this technique should only be considered following rigorous exclusion of retrobulbar pathology and careful attention towards early detection of raised intraocular pressure.
Collapse
|