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Ravinder Kaur

Publications and source records attributed to Ravinder Kaur.

16 recordsLinked to original sources
PubMed2006

Impact assessment and recommendation of alternative conjunctive water use strategies for salt affected agricultural lands through a field scale decision support system - a case study.

Conjunctive use of saline/non-saline irrigation waters is generally aimed at minimizing yield losses and enhancing flexibility of cropping, without much alteration in farming operations. Recommendation of location-specific suitable conjunctive water use plans requires assessment of their long-term impacts on soil salinization/sodification and crop yield reductions. This is conventionally achieved through long-term field experiments. However such impact evaluations are site specific, expensive and time consuming. Appropriate decision support systems (DSS) can be time-efficient and cost-effective means for such long-term impact evaluations. This study demonstrates the application of one such (indigenously developed) DSS for recommending best conjunctive water use plans for a, rice-wheat growing, salt affected farmer's field in Gurgaon district of Haryana (India). Before application, the DSS was extensively validated on several farmers and controlled experimental fields in Gurgaon and Karnal districts of Haryana (India). Validation of DSS showed its potential to give realistic estimates of root zone soil salinity (with R = 0.76-0.94; AMRE = 0.03-0.06; RMSPD = 0.51-0.90); sodicity (with R = 0.99; AMRE = 0.02; RMSPD = 0.84) and relative crop yield reductions (AMRE = 0.24), under existing (local) resource management practices. Long term (10 years) root zone salt build ups and associated rice/wheat crop yield reductions, in a salt affected farmer's field, under varied conjunctive water use scenarios were evaluated with the validated DSS. It was observed that long-term applications of canal (CW) and tube well (TW) waters in a cycle and in 1:1 mixed mode, during Kharif season, predicted higher average root zone salt reductions (2-9%) and lower rice crop yield reductions (4-5%) than the existing practice of 3-CW, 3-TW, 3-CW. Besides this, long-term application of 75% CW mixed with 25% TW, during Rabi season, predicted about 17% lower average root-zone salt reductions than the cyclic applications of (1-CW, 1-TW, 2-CW) and (2-CW, 1-TW, 1-CW, i.e., existing irrigation strategy). However, average wheat crop yield reductions (16-17%) simulated under all these strategies were almost at par. In general, cyclic-conjunctive water use strategies emerged as better options than the blending modes. These results were in complete confirmation with actual long-term conjunctive water use experiments on similar soils. It was thus observed that such pre-validated tools could be efficient means for designing, local resource and target crop yield-specific, appropriate conjunctive water use plans for irrigated agricultural lands.

Agriculture↗
PubMed2006

Spatial characterization and prioritization of heavy metal contaminated soil-water resources in peri-urban areas of National Capital Territory (NCT), Delhi.

Due to rapid industrialization and urbanization during last two decades, contamination of soils by heavy metals is on an increase globally. Lands under peri-urban agriculture are the worst affected. In NCT, Delhi about 14.4% of land area is chemically degraded. In order to take care of this problem, recently the Supreme Court of India ordered to shift various non-confirming (about 39,000 units) industries to regions outside NCT, Delhi. However in spite of this, there have been several reports and parliamentary debates on the phyto-toxicity and extensive accumulation of heavy metals in the region. Literature review revealed that the basis of these debates is a few studies on some point locations in/around Delhi. It was further observed that information on the distribution and extent of heavy metal pollution problem in the region was completely missing. The present study was thus basically aimed at assessing the spatial distribution/extent and type of heavy metal pollution in the study area, for enabling future designing of appropriate site-specific management measures by the decision makers. For this, detailed spatial information on bio-available heavy metal concentrations in the soils and surface/sub-surface waters of NCT (Delhi) was generated through actual soil/water surveys, standard laboratory methods and GIS techniques. The study showed that concentration of all micronutrients (viz. Zn: 0.05-0.18 ppm; Cu: in traces; Fe: 0-0.5 ppm; and Mn: 0-1.2 ppm) and most heavy metals (viz. Ni: 0-0.7 ppm; Pb: 0-0.15 ppm and Cd: in traces) in the surface/sub-surface irrigation waters were well within permissible limits. However Cr concentrations in irrigation waters of Alipur and Shahdara blocks were far above their maximum permissible limit of 1 ppm. It was further observed that Ni and Cr concentrations in the drinking waters of almost entire test area were far above maximum permissible levels of 0.02 and 0.01 ppm, respectively. Bio-available concentrations of several heavy metals (viz. Pb: 0.1-2 ppm; Cd: traces; Ni: 0.05-2 ppm and Cr: 0-0.4 ppm) in the study area soils were also observed to be well within the maximum permissible limits. However there were point Cu contaminations (5-10 ppm) in the sewage-sludge amended soils of vegetable growing areas near south Shahdara block. This was attributed to increased Cu availability due to oxidized acidic conditions generated by over-irrigation of agricultural lands. Available Mn concentrations in Kanjhawala, western Najafgarh and Alipur soils were also observed to be above maximum permissible limit of 10 ppm. This was observed to be mainly due to the geology (i.e. presence of Mn rich sedimentary rocks) and prevalence of reduced acidic conditions, due to paddy cultivation, in these areas. It was further observed that there is acute zinc (Zn) deficiency (< 0.6 ppm) in paddy growing soils of north Kanjhawala, Alipur and some parts of Najafgarh and Shahdara blocks due to extensive leaching of available Zn fractions to lower soil horizons. Similar available Zn deficiencies in high pH (8.5) soils of areas around Bamnoli village in E-Najafgarh block were also observed.

Agriculture↗
PubMed2006

Vaginal microflora in postmenopausal women on hormone replacement therapy.

To study the spectrum of vaginal microflora in postmenopausal women on hormone replacement therapy (HRT) and to compare the efficacy of Papanicolaou (Pap) smears with other methods for their detection. Eighty postmenopausal women were recruited for the study. These included 40 women who had attained spontaneous and were on HRT (User 1); 20 hysterectomised women on only estrogen therapy (User 2) and 20 controls (Non users). Their clinical data was recorded and specimens were collected for vaginal cultures (for aerobic bacteria and fungi), vaginal pH, Gram stain and Pap stain on cervical-vaginal smears and toluidine blue on wet smears. Vaginal pH was significantly lower in Users as compared to Non users. Lactobacilli and Gardnerella were more frequently isolated from Users while Bacteroides and E. coli were more common in Non users. Cultures were significantly more sensitive than Gram stained direct vaginal smears in detection of aerobic bacteria; however, Candida could be detected on Gram stain alone in all the cases. Frequency of detection of organisms significantly improved by application of Gram stain to the cervico-vaginal smears. However, clinically relevant organisms like Candida, Gardnerella and Mobiluncus could be identified on Pap smears alone in >50% cases. Lactobacilli could be readily identified in Pap smears in 98% cases. Wet mounts could detect cocci more easily as compared to Pap smears. Altered vaginal microbial profile in post menopausal women receiving HRT may cause bacterial and fungal vaginitis. Although culture studies remain the gold standard to detect these microorganisms, Pap and Gram stains and wet smears provide useful supplements and may be used as alternative procedures especially in resource limited settings lacking adequate culture facilities.

Bacteria↗
PubMed2005

Redox properties of wild-type and heme-binding loop mutants of bacterial cytochromes C measured by direct electrochemistry.

We have used protein film voltammetry (PFV) to determine the midpoint potentials of the Pseudomonas aeruginosa, Hydrogenobacter thermophilus, and Nitrosomonas europaea wild-type monoheme cytochromes c (cyts c; PA, HT, and NE, respectively), as well as PA N64Q, HT Q64N, and NE V65delta mutants, as a function of pH, and buffer conditions. Recent studies have suggested that the identity of the 64 position of the heme-binding loop (either Asn or Gln) strongly influences the conformation of the Met ligand that binds the heme iron. The PFV studies reveal that HT and NE possess significantly lower potentials (wild-type cyts c having E(m) values of +227 and +250 mV vs SHE) than PA (+290 mV) in 50 mM phosphate buffer, pH 7 at 3 degrees C. The HT Q64N mutant rises in potential compared to wild-type, and the PA N64Q mutant has a lower potential, indicating relationships between Met ligand fluxion, hydrogen bonding to the Met ligand, and redox chemistry. Surprisingly, NE V65delta, possessing a heme binding loop nearly identical to that of the PA protein, displayed an E(m) of +232 mV, even lower than wild-type NE. These data are discussed in terms of models of Met ligand properties and proton dependence.

Bacterial Proteins↗
PubMed2005

Polymorphism in IGF-2 as a surrogate marker for predisposition towards tobacco chewing-mediated oral cancer.

Insulin and insulin-like growth factors (IGFs) are major determinants of proliferation and apoptosis, thereby playing a significant role in carcinogenesis. Epidemiological evidence associates high levels of INS and IGFs with an increased risk of cancer. Polymorphism of the genes involved in insulin-signaling pathways has been associated with a variable risk for neoplasms in different ethnic and environmental backgrounds. In this study, using PCR-RFLP-based assays, we investigated the distribution of genetic polymorphism in INS and IGF-2 genes in tobacco chewing-mediated oral cancer patients (n = 60) and healthy controls (n = 45) of Indian ethnic origin. The genotyping was performed for +1127 INS-Pst1 in INS and +3580 IGF-2-Msp1 in IGF-2. The frequencies of the IGF-2 genotypes AG, GG and AA found in oral cancer patients were 0.68, 0.2 and 0.12, respectively, whereas in noncancer controls these frequencies were 0.27, 0.71 and 0.02. Frequencies of each allele, i.e. CT, TT and CC of INS gene, were found to be nearly equal in the tumor (0.22, 0.75 and 0.03) as well as the normal (0.27, 0.67 and 0.06) population. A significant difference was observed in genotypic frequencies of IGF-2 and INS in the Indian ethnic population as compared to the Caucasian, African and Hispanic populations. Polymorphism at +1127 INS-Pst1 locus of INS gene does not show an implication in oral cancer, whereas the genotype AG or AA at +3580 IGF-2-Msp1 locus of IGF-2 is associated with progression and increased risk of oral cancer. From our study we can conclude that single nucleotide polymorphisms in the IGF-2 gene can be used as a marker for prediction of the risk of oral carcinogenesis.

Carcinoma, Squamous Cell↗
PubMed2005

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome: ultrasonography as a diagnostic tool.

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome is characterized by symmetrical synovitis and swelling of both the upper and lower extremities. The anatomical determinant of RS3PE is predominantly extensor tenosynovitis as revealed by magnetic resonance imaging (MRI). Given the cost constraints, time, and expertise required in carrying out MRI and ease in diagnosing tenosynovitis by ultrasound, we utilized high-frequency ultrasonography (USG) for evidence of tenosynovitis of the distal tendons in patients with RS3PE. Diagnosis of tenosynovitis was made on the basis of anechoic or hypoechoic signals around the tendon sheaths in both transverse and longitudinal planes. Flexor and extensor tendons at the wrist and metacarpal heads and extensor digitorum longus (EDL) tendons at the ankle were evaluated with a 7.5-10-MHz linear probe. There were ten patients (seven males) with a mean age of 59.5 years (range: 52-78 years) and mean disease duration of 6.1 months (range: 1.5-12 months). Disease onset was acute in all of the cases. Pitting edema of the hands was present in all except two patients whereas four patients, in addition, had edema of the feet. Edema was symmetrical in seven patients. Inability to make a complete fist was noted in all. Tenosynovitis of extensor and flexor tendons at the wrist and the metacarpal heads was documented in all patients with edema of the hands. In seven cases extensor tendon tenosynovitis was more prominent compared to the flexor tendons. Tenosynovitis of EDL tendons was detected in six cases. Dramatic relief with low-dose prednisolone was noted in all patients within 6 weeks of therapy. At a mean follow-up of 10.1 months all patients had marked relief in edema of extremities and improvement in the grip strength. Our study confirms that tenosynovitis of both flexor and extensor tendons at the wrist and extensor tendons of the feet is the hallmark of RS3PE syndrome. USG is a reliable and cost-effective modality for evaluation of patients with suspected RS3PE.

Aged↗
PubMed2005

The patterning of hypodontia in a group of young adults in Sheffield, UK.

OBJECTIVE: Identifying the patterning of congenitally absent teeth will contribute to understanding the aetiology of hypodontia. The aim of this study was to investigate patterns of hypodontia in a group of young adults in Sheffield, UK involving specific tooth types, gender differences and maxilla:mandible and left:right correlations. METHODS: The patients were 198 unrelated Caucasian young adults (86 males and 112 females) with non-syndromic hypodontia. Statistical methods included the multivariate techniques of cluster analysis and principal components analysis and associated display devices of circular dotplots and biplots. Autologistic regression was used to model the relationship of the presence or absence of a particular tooth to the status of other teeth. RESULTS: The results revealed distinct patterns of dependence. Common patterns included either third molars and second premolars missing in all quadrants and/or combinations of these two tooth types and the incisors. The gender of the patient and the severity of hypodontia did not have a significant effect on patterns of tooth type absence. If a tooth was missing, the odds ratios that the same tooth type in the horizontally or vertically opposite quadrant was also missing were some 20 times higher than if the tooth was present. For diagonally opposite quadrants the dependence was much weaker. CONCLUSIONS: These statistical techniques are valuable for increasing understanding of hypodontia and identifying groups of patients for genetic studies.

Adolescent↗
PubMed2004

Folding, conformational changes, and dynamics of cytochromes C probed by NMR spectroscopy.

NMR spectroscopy has become a vital tool for studies of protein conformational changes and dynamics. Oxidized Fe(III)cytochromes c are a particularly attractive target for NMR analysis because their paramagnetism (S = (1)/(2)) leads to high (1)H chemical shift dispersion, even for unfolded or otherwise disordered states. In addition, analysis of shifts induced by the hyperfine interaction reveals details of the structure of the heme and its ligands for native and nonnative protein conformational states. The use of NMR spectroscopy to investigate the folding and dynamics of paramagnetic cytochromes c is reviewed here. Studies of nonnative conformations formed by denaturation and by anomalous in vivo maturation (heme attachment) are facilitated by the paramagnetic, low-spin nature of native and nonnative forms of cytochromes c. Investigation of the dynamics of folded cytochromes c also are aided by their paramagnetism. As an example of this analysis, the expression in Escherichia coli of cytochrome c(552) from Nitrosomonas europaea is reported here, along with analysis of its unusual heme hyperfine shifts. The results are suggestive of heme axial methionine fluxion in N. europaea ferricytochrome c(552). The application of NMR spectroscopy to investigate paramagnetic cytochrome c folding and dynamics has advanced our understanding of the structure and dynamics of both native and nonnative states of heme proteins.

Algorithms↗
PubMed2003

Fibrin glue versus N-butyl-2-cyanoacrylate in corneal perforations.

OBJECTIVE: To compare the efficacy of fibrin glue and N-butyl-2-cyanoacrylate in corneal perforations. DESIGN: Randomized, controlled clinical trial. PARTICIPANTS: Forty-one patients (41 eyes) with corneal perforations up to 3 mm in diameter with a positive Seidel's test were randomly assigned to two groups (1 and 2). INTERVENTION: Group 1 comprised 19 eyes treated with fibrin glue, and group 2 comprised 22 eyes treated with N-butyl-2-cyanoacrylate. MAIN OUTCOME MEASURES: Number of eyes with successful healing, time required for healing, status of corneal vascularization, and complications were compared in the two groups. Power calculation was performed at alpha = 0.05. RESULTS: Fifteen (79%) eyes had successful healing of corneal perforation in group 1, compared with 19 (86%) eyes in group 2 (P > 0.05) at 3 months' follow-up. The power to detect a difference between the two groups was 10%. Corneal perforation healed within 6 weeks in 12 (63%) eyes in group 1 and 7 (31.8%) eyes in group 2 (P < 0.05). Reapplication of glue was required in six (31.5%) eyes in group 1 and seven (31.4%) eyes in group 2 during the first 3 months of follow-up. The mean number of applications per eye was 1.37 in group 1 and 1.36 in group 2. An increase in deep corneal vascularization was observed in 2 (10.5%) eyes in group 1 and 10 (45.5%) eyes in group 2 (P < 0.05). Giant papillary conjunctivitis occurred in one (5%) eye in group 1 and eight (36.4%) eyes in group 2 (P < 0.05). CONCLUSIONS: Fibrin glue and cyanoacrylate tissue adhesive are both effective in the closure of corneal perforations up to 3 mm in diameter. Fibrin glue provides faster healing and induces significantly less corneal vascularization, but it requires a significantly longer time for adhesive plug formation.

Adolescent↗
PubMed2003

Cryptococcal meningitis in pediatric AIDS.

Cryptococcus neoformans is an infrequent cause of meningitis in children. We report two cases of HIV positive children of HIV non-reactive parents who were diagnosed as suffering from cryptococcal meningitis. Treatment with amphotericin B and flucytosine was instituted in both the children who recovered and are doing well.

AIDS-Related Opportunistic Infections↗
PubMed2002

Cryptococcal meningitis in a neonate.

A case of cryptococcal meningitis in a neonate born to an HIV-negative women is described. The cryptococcal infection was proved using standard microbiological and antigen detection techniques. Although cryptococcal meningitis has previously been described in both immunocompromised and immunocompetent children, the present case represents youngest case of cryptococcosis reported to date.

Anti-Bacterial Agents↗
PubMed2002

Intestinal parasites in children with diarrhea in Delhi, India.

The parasitic causes of diarrhea in children in Delhi were determined by the direct smear technique; stool specimens of 127 children were examined for intestinal parasites. In 59 cases (46.5%) intestinal helminths and protozoa were demonstrated. Ascaris lumbricoides was observed in 1 (0.8%) case, while Trichuris trichiura was the finding in 3 (2.4%). Protozoal parasites included Giardia intestinalis and Entamoeba histolytica in 14 (11%) cases each, Balantidium coli in 3 (2.4%) cases and Cryptosporidium spp in 24 (18.9%) patients. Mixed infection was not seen in any of the cases. Intestinal parasites may increase susceptibility to infection with other intestinal pathogens and therefore with the help of a simple technique, like direct fecal smear examination. rapid diagnosis can be made and specific therapy instituted.

Adolescent↗
PubMed2002

Etiology of endemic viral hepatitis in urban North India.

This study was carried out to determine the presence of markers of hepatitis viruses in patients with acute liver disease. Coinfection of HAV, HBV, HCV, and HEV was studied. Sera from 306 patients with a clinical diagnosis of acute liver disease were tested for the presence of anti-HAV antibody, HBsAg, anti-HBc antibody, anti-HBs antibody, anti-HCV antibody and IgM anti-HEV antibody by ELISA. Liver function tests were correlated with the presence of infection. Of the 306 cases, 7 (2.3%) had IgM anti-HAV, 9 (2.9%) had IgM anti-HBc, 37 (12.1%) had HBsAg, 84 (27.4%) had anti-HBs, 10 (3.3%) were HCV infected and 63 (20.6%) had IgM anti-HEV. There was no significant difference in the clinical and liver function profiles of infected and uninfected patients. Similarly, no difference was observed in cases coinfected with more than one virus compared with those infected with a single pathogen. HEV had the highest prevalence amongst our cases. There was no difference in the clinical profiles of patients with non-A, non-B, non-C, non-E hepatitis by antibody assays and testing for viremia could be helpful in making the correct diagnosis.

Acute Disease↗
PubMed2000

Curvularia dacryocystitis: report of two cases.

Two cases of ocular mycosis caused by the genus Curvularia are reported. In these cases, the infection was localised to the lacrimal sac only and presented in the form of acute to chronic dacryocystitis. Interestingly, neither of the hosts was immunocompromised. The authors have not been able to find a similar presentation of ocular mycosis caused by Curvularia localised to the lacrimal sac in the literature. The relevant literature pertaining to ocular involvement with this fungus is discussed. The authors recommend the use of oral fluconazole for a minimum of two weeks for the treatment of such infections as a good therapeutic response was obtained with this agent in both their cases.

Journal Article↗