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R K Gupta

Publications and source records attributed to R K Gupta.

At least 19 recordsLinked to original sources
PubMed2006

Methoxychlor causes mitochondrial dysfunction and oxidative damage in the mouse ovary.

Methoxychlor (MXC) is an organochlorine pesticide that reduces fertility in female rodents by causing ovarian atrophy, persistent estrous cyclicity, and antral follicle atresia (apoptotic cell death). Oxidative damage resulting from reactive oxygen species (ROS) generation has been demonstrated to lead to toxicant-induced cell death. Thus, this work tested the hypothesis that MXC causes oxidative damage to the mouse ovary and affects mitochondrial respiration in a manner that stimulates ROS production. For the in vitro experiments, mitochondria were collected from adult cycling mouse ovaries, treated with vehicle (dimethyl sulfoxide; DMSO) or MXC, and subjected to polarographic measurements of respiration. For the in vivo experiments, adult cycling CD-1 mice were dosed with either vehicle (sesame oil) or MXC for 20 days. After treatment, ovarian mitochondria were isolated and subjected to measurements of respiration and fluorimetric measurements of H2O2 production. Some ovaries were also fixed and processed for immunohistochemistry using antibodies for ROS production markers: nitrotyrosine and 8-hydroxy-2'-deoxyguanosine (8-OHG). Ovaries from in vivo experiments were also used to measure the mRNA expression and activity of antioxidants such as Cu/Zn superoxide dismutase (SOD1), glutathione peroxidase (GPX), and catalase (CAT). The results indicate that MXC significantly impairs mitochondrial respiration, increases production of H2O2, causes more staining for nitrotyrosine and 8-OHG in antral follicles, and decreases the expression and activity of SOD1, GPX, and CAT as compared to controls. Collectively, these data indicate that MXC inhibits mitochondrial respiration, causes ROS production, and decreases antioxidant expression and activity in the ovary, specifically in the antral follicles. Therefore, it is possible that MXC causes atresia of ovarian antral follicles by inducing oxidative stress through mitochondrial production of ROS.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2006

Timing of monoclonal antibody for seasonal RSV prophylaxis in the United Kingdom.

Respiratory syncytial virus (RSV) infection produces more severe disease and increased hospitalization rates in high-risk babies. The monoclonal antibody palivizumab offers protection against complications, and the first of five monthly doses should be administered before the onset of community RSV activity. However, the required real-time prediction of this onset is problematic. We attempted to identify seasonal RSV patterns by retrospectively examining 10 years of laboratory reports for RSV and clinical episode reports for certain respiratory presentations in both primary and secondary care. Analysis of hospital laboratory reports, incidence of acute bronchitis in primary care, and hospital admissions for acute bronchitis and bronchiolitis in young children revealed a consistent increase in RSV activity during week 43 each year. Promptly commencing prophylaxis during the second week of each October (week 42) would precede the onset of the RSV season in the United Kingdom, and provide coverage until its decline in mid-March.

Antibodies, Monoclonal↗
PubMed2006

Diffusion tensor imaging in polymicrogyria: a report of three cases.

INTRODUCTION: Polymicrogyria (PMG), a neuronal migration disorder, commonly manifests as a seizure disorder. The aim of this study was to look for the abnormalities in the underlying white matter using diffusion tensor imaging (DTI) that appeared normal on conventional magnetic resonance imaging (MRI) in patients with PMG. METHODS: DTI was performed in three patients with PMG and eight age- and sex-matched healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated for the cortex and adjoining subcortical white matter in both controls and patients. RESULTS: We observed a significantly decreased mean FA value with no significant change in the MD value in subcortical white matter underlying polymicrogyric cortex (FA = 0.23+/-0.04, MD = 1.0+/-0.05 x 10(-3) mm(2)/s) as compared to both contralateral (FA = 0.32+/-0.04, MD = 1.0+/-0.05 x 10(-3) mm(2)/s) and normal control (FA = 0.32+/-0.04, MD = 1.0+/-0.06 x 10(-3) mm(2)/s) white matter. Significantly increased MD and decreased FA values were also observed in the polymicrogyric cortex (FA = 0.08+/-0.01, MD = 1.2+/-0.10 x 10(-3) mm(2)/s) as compared to normal contralateral (FA = 0.12+/-0.04, MD = 1.1+/-0.09 x 10(-3) mm(2)/s) and normal control (FA = 0.12+/-0.01, MD = 1.1+/-0.09 x 10(-3) mm(2)/s) cortex. CONCLUSION: Significantly decreased FA values with no change in MD values in the subcortical white matter subjacent to polymicrogyric cortex reflect microstructural changes in the white matter probably due to the presence of ectopic neurons.

Adult↗
PubMed2006

Fentanyl-augmented MRCP.

BACKGROUND: Drugs such as secretin and morphine have been used to augment the visualization of magnetic resonance cholangiopancreatography (MRCP). This study investigated the effectiveness of intravenous administration of a synthetic opioid, fentanyl, in improving the MRCP image quality. METHODS: Thirty consecutive patients with a provisional diagnosis of benign biliary and/or pancreatic disease underwent MRCP. Coronal single-shot fast spin-echo heavily T2-weighted dynamic MRCP images were generated before and at every minute for 10 min after intravenous administration of fentanyl citrate at a dose of 1.0 mug/kg. Pre- and postinjection images were compared and analyzed qualitatively and quantitatively. RESULTS: Qualitatively, visualization of intrahepatic bile ducts, common bile duct, and main pancreatic duct improved after fentanyl injection in five (16%), 11 (37%), and 19 (63%) patients, respectively. The pancreatobiliary junction and common channel were visualized better after fentanyl injection in eight of the 18 patients (44%). Quantitatively, signal intensity and diameters of the intrahepatic ducts, common bile duct, and main pancreatic duct measured at corresponding points on pre- and postinjection images showed an increase above preinjection values in 28 (93%), 27 (90%), and 21 (70%) and in 18 (60%), 26 (86%), and 22 (73%), respectively, and these changes were highly significant at all sites (p < 0.001). CONCLUSIONS: Intravenous administration of fentanyl before MRCP improves qualitative and quantitative visualization of the ductal system anatomy that may be of value in clinical diagnosis and management.

Adolescent↗
PubMed2006

Development of a fluorescence assay for the detection of L-ficolin-MASP in serum or purified samples.

A fluorescence assay for the detection of L-ficolin-MASP in human serum or purified sample was developed by measuring the cleavage of fluorescent amide substrate by L-ficolin associated MASPs bound to the lipoteichoic acid (LTA). LTA (Staphylococcus aureus DSM 20233) was coated on NuncMaxisorp microtiter plates and serum or purified sample incubated overnight at 4 degrees C to allow the L-ficolin-MASP to bind LTA. Assay conditions for binding and complete cleavage of fluorescent amide substrate were standardized. The optimum temperature, incubation time and molarity of NaCl for LTA-ficolin binding were found to be 4 degrees C for 6 h at 1 M NaCl concentration. The optimum incubation time and pH for complete cleavage of fluorescent amide substrate by LTA bound L-ficolin associated MASP were found to be 2 h at pH 8.5. LTA-ficolin binding was found to be highly specific and was inhibited completely by LTA but not with mannose. A calibration curve was prepared by using the purified ficolin-MASP complex (1 to 12 mug/ml) and could be used to find concentration of ficolin-MASP complex in normal human serum.

Chemistry Techniques, Analytical↗
PubMed2006

Subarachnoid haemorrhage as a presentation of cerebral venous sinus thrombosis.

Cerebral venous sinus thrombosis can present with a variety of clinical symptoms ranging from isolated headache to deep coma. Subarachnoid haemorrhage is a rare presentation. In the report, we describe a case of non-puerperal venous thrombosis of many dural sinuses manifesting on imaging solely as localized subarachnoid haemorrhage without underlying parenchymal involvement.

Adult↗
PubMed2006

Impact of Ni(II), Zn(II) and Cd(II) on biogassification of potato waste.

A study was conducted on anaerobic digestion of potato waste and cattle manure mixture, inoculated with 12% inoculum and diluted to 1:1 substrate water ratio at 37 +/- 1 degrees C. Initially pH of substrate was found to be 4.5 to 5.0. Lime and sodium bicarbonate solutions were employed to adjust the pH to 7.5. Biogas production continued up to 10 and 7 days, when lime and sodium bicarbonate solutions were used to adjust the pH, respectively. Biogassification potential was studied in response to different ratio of waste and cattle manure. Biogas production rate was higher when potato waste and cattle manure were used in 50:50 ratio. Effect of two different concentrations (2.5 and 5.0 ppm) of three heavy metals viz. (Ni (II), Zn (II) and Cd (II)) on anaerobic digestion of substrate (potato waste--cattle manure, 50:50) was studied. At 2.5 ppm, all the three heavy metals increased biogas production rate over the control value. The percentage increase in biogas production over the control was highest by Cd, followed by Ni and Zn. In all the treatments, methane content of biogas increased with increase in time after feeding. Various physico-chemical parameters viz. total solids, total volatile solids, total organic carbon and chemical oxygen demand considerably declined after 7 days of digestion and decline was greater in presence of heavy metals as compared to control. The physico-chemical parameters revealed maximum decrease in the presence of 2.5-ppm concentrations of heavy metals with the substrate. Among all the three heavy metals employed in the study, Cd++ at 2.5 ppm was found to produce maximum biogas production rate. The use of three heavy metals to enhance biogas production from potato and other horticultural waste is discussed.

Animals↗
PubMed2006

Assessment of white matter damage in subacute sclerosing panencephalitis using quantitative diffusion tensor MR imaging.

BACKGROUND AND PURPOSE: Subacute sclerosing panencephalitis (SSPE), a rare progressive degenerative disease, is caused by persistent infection with a defective measles virus. The correlation between the clinical staging and MR imaging is usually poor. The aim of the study was to investigate the role of diffusion tensor imaging (DTI) in the early detection of white matter damage in SSPE in the presence of normal findings on conventional imaging. METHODS: DTI was performed in 21 patients in stage II SSPE and 10 age/sex-matched healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated in the periventricular white matter, corpus callosum, and posterior limb of the internal capsule in patients with normal and abnormal findings on conventional imaging as well as healthy controls. RESULTS: The patients were grouped into those with normal (n = 11) and abnormal (n = 10) findings on conventional imaging for the purpose of quantitative DTI analysis. Abnormal- and normal-appearing white matter on T2-weighted images showed significantly decreased FA values in all the regions compared with those in healthy controls. MD values were significantly increased in the periventricular white matter region of the frontal and parietooccipital lobe in patients with normal as well as abnormal findings on conventional imaging compared with those in healthy controls. CONCLUSION: DTI detects early white matter abnormalities that may have significant therapeutic implication, even in the presence of normal findings on conventional imaging, in patients with SSPE.

Adolescent↗
PubMed2006

Vitex negundo Linn (VN) leaf extract as an adjuvant therapy to standard anti-inflammatory drugs.

BACKGROUND & OBJECTIVES: Leaves of Vitex negundo (VN) have been investigated for their antiinflammatory activity in past, including its mechanism of action. However, nobody has evaluated its potential role as an adjuvant with standard anti-inflammatory therapy. Therefore, the present study was undertaken to investigate interaction of ethanolic leaf extract of VN Linn with standard anti-inflammatory drugs in sub-effective doses per orally (PO) to evaluate its potential role as an adjuvant therapy. METHODS: Carrageenin induced hind paw oedema and cotton pellet granuloma test in albino rats were employed to study interaction of Vitex negundo (VN) leaf extract with standard antiinflammatory drugs in sub-effective doses per orally to evaluate its potential role as an adjuvant therapy. RESULTS: The sub-effective dose of VN potentiated anti-inflammatory activity of phenlbutazone and ibuprofen significantly in carrageenin induced hind paw oedema and cotton pellet granuloma models. INTERPRETATION & CONCLUSION: The potentiation of anti-inflammatory activities phenlbutazone and ibuprofen by VN indicates that it may be useful as an adjuvant therapy along with standard antiinflammatory drugs.

Animals↗
PubMed2005

Health innovation networks to help developing countries address neglected diseases.

Gross inequities in disease burden between developed and developing countries are now the subject of intense global attention. Public and private donors have marshaled resources and created organizational structures to accelerate the development of new health products and to procure and distribute drugs and vaccines for the poor. Despite these encouraging efforts directed primarily from and funded by industrialized countries, sufficiency and sustainability remain enormous challenges because of the sheer magnitude of the problem. Here we highlight a complementary and increasingly important means to improve health equity: the growing ability of some developing countries to undertake health innovation.

Biomedical Research↗
PubMed2005

Preparation and characterization of electrically conducting Langmuir-Blodgett films of poly(N-octadecylaniline).

A stable monolayer of N-octadecylaniline containing stearic acid at the air-water interface has been obtained. However, the Langmuir monolayer of pure poly(N-octadecylaniline) was not stable, but mixed Langmuir-Blodgett films of this polymer with stearic acid in different ratios as a spreading aid were stable. The electrical conductivity of these films increased by five orders of magnitude after doping with iodine as compared to that before iodine doping (5.8x10(-7) S cm(-1)). Temperature-dependent electrical conductivity suggested that these films were semiconducting in nature with low thermal activation energy. Impedance analyses of these films revealed that the equivalent circuit for poly(N-octadecylaniline) was (RQ) whereas that for mixed poly(N-octadecylaniline) with stearic acid was (RQ)(RQ).

Journal Article↗
PubMed2005

Comparative evaluation of magnetization transfer contrast and fluid attenuated inversion recovery sequences in brain tuberculoma.

AIM: To compare T1-weighted magnetization transfer (MT) with fluid attenuated inversion recovery (FLAIR) imaging for evaluating conspicuity and number of lesions in individuals with brain tuberculoma. MATERIALS AND METHODS: In all 28 patients with brain tuberculoma underwent MR examination using fast spin-echo (FSE) T2, spin-echo (SE) T1, T1-weighted MT and FLAIR imaging. Post-contrast T1-weighted MT imaging was taken as the gold standard for assessing the number of lesions. Tuberculomas detected both on T1-weighted MT and FLAIR imaging were examined for the wall to be defined, and were divided into two groups on the basis of presence (group 1) or absence (group 2) of perilesional oedema visible on FLAIR imaging. The mean signal intensity of the wall of the lesions and adjacent oedema or brain parenchyma was analyzed qualitatively and quantitatively. RESULTS: The number of lesions detected on T1-weighted MT was higher than on FLAIR imaging (209 versus 163). Conspicuity in both groups was better on T1-weighted MT images qualitatively as well as quantitatively. The difference in the signal intensity of the wall of the lesion and perilesional oedema was statistically significant only on T1-weighted MT images in group 1 (p=0.0003 versus 0.3), whereas in group 2 it was statistically significant both on T1-weighted MT and FLAIR imaging (p=0.009 versus 0.05). CONCLUSION: FLAIR imaging is not helpful in the examination of brain tuberculomas compared with T1-weighted MT imaging, as it neither contributes to the characterization of lesion nor assesses the true disease load.

Adolescent↗
PubMed2005

Presence of TT virus infection in chronic hepatitis patients from a hospital in New Delhi, India.

BACKGROUND & OBJECTIVE: The recent discovery of a novel parenterally transmitted, unenveloped, single-stranded DNA virus called TT virus (TTV) in chronic hepatitis patients with unclear pathogenesis throughout the world led us to investigate, its presence in chronic hepatitis patients attending a hospital in New Delhi, India, and to evaluate its role in liver disease. METHODS: TT virus DNA was investigated in serum samples of 70 patients with various types of chronic hepatitis, and 100 healthy subjects from New Delhi, India by nested PCR using the primers that belonged to UTR (A) region of the genome. RESULTS: TTV DNA was detected in 6 of 23 patients (26%) with type B chronic hepatitis, 3 of 20 patients (15%) with type C chronic hepatitis, and 12 of 100 subjects (12%) from healthy control group with normal liver function profile tests. None of the 27 non-B, non-C chronic hepatitis patients had TTV DNA positivity. The prevalence of TTV was significantly higher in type-B chronic hepatitis patients as compared to normal subjects (P< 0.05) but comparable to type C chronic hepatitis patients. The clinical course and biochemical profiles of type B, or type C chronic hepatitis patients co-infected with TTV did not differ significantly from those without TTV infection. INTERPRETATION & CONCLUSION: Interestingly, in chronic hepatitis patients, TTV was always associated with either hepatitis B or C virus indicating a likely parenteral route of transmission. All TTV-positive subjects in healthy control group showed normal clinical and biochemical profiles. Thus, the presence of TTV infection is unlikely to influence the course of chronic hepatitis related to hepatitis B virus (HBV) or hepatitis C virus (HCV) or cause liver diseases in healthy subjects.

Case-Control Studies↗
PubMed2005

Antinociceptive activity of Vitex-negundo Linn leaf extract.

Tail flick test in rats and acetic acid induced writhing in mice were employed to study the antinociceptive activity of ethanolic leaf extract of Vitex-negundo (VN) (100, 250 and 500 mg/kg, p.o). The effect was compared with meperidine (40 mg/kg, sc) in tail flick method and aspirin (50 mg/kg, p.o) in writhing test as a standard control respectively. An interaction with naloxone hydrochloride was also studied in tail flick method for its mechanism of central analgesic action. The test drug showed significant analgesic activity in dose dependant manner in both the experimental models. In comparison to standard drug (meperidine), more than ten times dose of VN extract was required to produce comparable significant antinociceptive activity. The sub-effective dose (5 mg/kg, po) of VN potentiated the analgesic activity of meperidine (4 mg/kg, sc) and aspirin (25 mg/kg, po). Naloxone (1 mg/kg, sc) did not reverse the analgesic effect of VN extract. Our observations suggest that VN possesses both central and peripheral analgesic activity. The central analgesic action does not seem to be mediated through opioid receptors. It, may prove to be a useful adjuvant therapy along with standard analgesic drug.

Acetic Acid↗
PubMed2005

An experimental evaluation of anticonvulsant activity of Vitex-negundo.

Maximal electroshock seizures (MES) in albino rats and pentylenetetarazole (PTZ) induced seizures in albino mice were used to study anticonvulsant activity of Vitex-negundo leaf extract. The ethanolic leaf extract of Vitex-negundo was administered orally in graded doses (250, 500 and 1000 mg/kg p.o) in both the experimental models and the effects were compared with diphenylhydantoin in MES method and valporic acid in PTZ induced seizures method as standard control respectively. The Vitex-negundo in the doses (250, 500 and 1000 mg/kg, p.o) did not show protection against MES to any significant extent but significant post-ictal depression was observed in the dose of 1000 mg/kg body weight in comparison to control. However, sub-protective dose of test drug (100 mg/ kg, p.o) potentiated the anticonvulsant action of diphenylhydantoin. The test drug in the dose (1000 mg/kg, po) showed 50% protection in clonic seizures and 24-hour mortality against PTZ induced seizures. It also decreased number and duration of convulsions significantly. Vitex-negundo potentiated anticonvulsant activity of valporic acid. The anticonvulsant activity of Vitex-negundo has not been found equi-effective with standard drugs. These findings suggest that Vitex-negundo possesses anticonvulsant activity particularly against PTZ induced convulsions. Moreover, the potentiation of diphenylhydantoin and valporic acid by Vitex-negundo indicates that it may be useful as an adjuvant therapy along with standard anticonvulsants and can possibly lower the requirement of diphenylhydantoin and valporic acid.

Animals↗