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Biomedical subjects

P K Singh

Publications and source records attributed to P K Singh.

At least 19 recordsLinked to original sources
PubMed2007

Inflation with air via a facepiece for facilitating insertion of a nasogastric tube: a prospective, randomised, double-blind study.

Insertion of a nasogastric tube is a routine procedure but during anaesthesia it is often difficult and time consuming. One hundred and sixty adults undergoing elective surgery under general anaesthesia were randomly divided into two groups. After induction of anaesthesia, neuromuscular blockade and tracheal intubation, a nasogastric tube was inserted through the nose with the head of the patient in the neutral position, either with or without prior inflation with air via a facepiece attached to a self-inflating bag applied firmly with the face. Insertion of the nasogastric tube was successful in 75/78 (96%) following inflation compared with 54/80 (68%) without inflation (p<0.001). In four patients receiving inflation, a fibreoptic endoscope was passed as far as the upper oesophageal sphincter; this revealed opening of the upper oesophageal sphincter during inflation.

Adult↗
PubMed2006

Ketamine for treatment of catheter related bladder discomfort: a prospective, randomized, placebo controlled and double blind study.

BACKGROUND: Intraoperative urinary catheterization might cause postoperative catheter related bladder discomfort (CRBD). We evaluated the efficacy of ketamine as a treatment modality for CRBD. METHODS: Fifty-four, ASA physical status I and II, male and female adult patients, having CRBD after elective percutaneous nephrolithotomy were randomized into two equal groups of 27 each. In the postoperative period, patients who complained of CRBD received medication depending upon group allocation. Group 1 (Control) received placebo, Group II (Ketamine) received i.v. ketamine 250 microg kg(-1). After induction of anaesthesia patients were catheterized with a 16 Fr Foley's catheter and the balloon was inflated with 10 ml distilled water. Grading of CRBD was done as none, mild, moderate and severe by a blinded observer at 0, 1, 2 and 6 h after operation. RESULTS: Ketamine reduced the incidence of CRBD (P<0.001) at 2 and 6 h along with reduction in severity (P<0.05) at 1 h compared with control. Higher incidence of mild sedation was observed in the ketamine group (P<0.05) which was not associated with any untoward effects. Operative time and intraoperative fentanyl requirement were similar in both the groups. CONCLUSION: I.V. ketamine (250 microg kg(-1)) is an effective treatment for reducing the incidence and severity of postoperative CRBD.

Adult↗
PubMed2005

High level expression of surface glycoprotein of rabies virus in tobacco leaves and its immunoprotective activity in mice.

A synthetic gene coding for the surface glycoprotein (G protein) of rabies virus was strategically designed to achieve high-level expression in transgenic plants. The native signal peptide was replaced by that of the pathogenesis related protein, PR-S of Nicotiana tabacum. An endoplasmic reticulum retention signal was included at C-terminus of the G protein. Tobacco plants were genetically engineered by nuclear transformation. Selected transgenic lines expressed the chimeric G protein at 0.38% of the total soluble leaf protein. Mice immunized intraperitoneally with the G protein purified from tobacco leaf microsomal fraction elicited high level of immune response as compared to the inactivated commercial viral vaccine. The plant-derived G protein induced complete protective immunity in mice against intracerebral lethal challenge with live rabies virus. The results establish that plants can provide a safe and effective production system for the expression of immunoprotective rabies virus surface protein.

Animals↗
PubMed2005

Morphological, physiochemical and molecular characterization of Anabaena strains.

A set of 30 Anabaena strains, isolated from diverse geographical regions of India, were characterized using morphological and physiochemical attributes as well as molecular marker profiles. Significant differences were observed among the Anabaena strains with regard to the shape and size of trichomes and individual cells within a filament, besides qualitative and quantitative aspects of phycobiliprotein accumulation and activities of enzymes involved in nitrogen metabolism. Analyses of molecular polymorphisms in a selected set of 13 Anabaena strains, using primers based on repetitive sequences in the genome, led to unambiguous differentiation of the strains as well as understanding of their genetic relationships. Informative morphological, physio-chemical and molecular characters have been identified that could aid in differentiation and utilization of Anabaena strains as bioinoculants or as sources of pigments.

Anabaena↗
PubMed2005

Short-term effect of complementary feeding frequency on total ad libitum consumption in 6- to 10-month-old breast fed Indian infants.

OBJECTIVE: To evaluate the short-term effect of frequency of complementary feeding on total ad libitum consumption in breast fed infants. METHODS: Twenty infants between 6 to 10 months of age were studied in a tertiary hospital in New Delhi for 48 hours. A traditional gruel made of rice and pulses (mean (SD) caloric density 54.22 (7.08) kcal/100 g) was offered in a randomized manner three (n = 10) or four (n = 10) times per day to the subjects over the first 24 hours with the subjects crossing over in the next 24 hours. They were allowed ad libitum breast feeding with no other food or fluid during the study period. Total caloric intake from breast milk and semisolids was computed for each day. RESULTS: There was no difference in the total caloric consumption with a semisolid feeding frequency of three or four times per day. The frequency of breast feeding and the breast feeding duration were also comparable (P > 0.05). However, breast milk intake was lower with a semisolid feeding frequency of 4 times/day (mean difference -61.2 g/d [95% confidence interval (CI) -122.2-0.32]; P = 0.051). The time required for feeding was higher (mean difference 14.75 min; P < 0.001), whereas the per meal intake of semisolids was lower with four semisolid feeds per day (mean difference -5.5 kcal/meal; [95% CI -10.19 to -0.81]; P = 0.024). CONCLUSION: In the short term, a change in semisolid feeding frequency from three to four times per day does not result in enhanced energy consumption because of lower breast milk intake.

Breast Feeding↗
PubMed2005

Clinical evaluation of the "T-Dagger": a new bedside percutaneous dilational tracheostomy device.

A number of percutaneous dilational tracheostomy devices are now available for clinical use. Recently, a new percutaneous dilational tracheostomy device, the "T-Dagger" (Criticure Invasives, India), has been introduced for rapid bedside percutaneous tracheostomy. In a prospective preliminary study, we have performed percutaneous dilational tracheostomy (PDT) using the T-Dagger in 20 adult ventilated patients in order to evaluate the safety and efficacy of the new device. The T-Dagger facilitated bedside PDT in about 3 min with no untoward incidents. There was no significant bleeding, pneumothorax, pneumomediastinum, tracheal wall injuries or difficulty in ventilation in any of the patients. We conclude that the T-Dagger shows early promise in bedside percutaneous dilational tracheostomy. However, controlled studies are required in a larger patient population before it can be recommended for routine use.

Adult↗
PubMed2005

Evaluation of capsaicin ointment at the Korean hand acupressure point K-D2 for prevention of postoperative nausea and vomiting.

The K-D2 point is the Korean hand acupressure point in Koryo Hand Therapy for prevention of postoperative nausea and vomiting. We evaluated the efficacy of capsaicin ointment at the K-D2 point in 186 patients undergoing laparoscopic cholecystectomy in a randomised, prospective, double-blind and placebo-controlled study. Patients were randomised to have either placebo ointment or capsaicin ointment applied to the K-D2 point of both hands 1 h before surgery under standardised anaesthesia. The ointment was removed 8 h later. Postoperative nausea and vomiting was evaluated 6 and 24 h following surgery. The incidence of postoperative nausea and vomiting was lower in the capsaicin group, with an absolute risk reduction (ARR) of 21%, a relative risk reduction (RRR) of 50% and a number-needed-to-treat (NNT) of 5 at 0-6 h (p = 0.001), and an ARR of 11%, a RRR of 85% and a NNT of 9 at 6-24 h (p = 0.003). The need for rescue anti-emetic treatment was also lower at 0-6 h (3 (3%) vs 11 (12%); p = 0.04) and at 6-24 h (5 (5%) vs 0; p = 0.02).

Acupuncture Points↗
PubMed2005

Short-term effect of oil supplementation of complementary food on total ad libitum consumption in 6- to 10-month-old breastfed Indian infants.

OBJECTIVES: To evaluate the short term effect of oil supplementation of complementary food on total ad libitum consumption in breastfed infants. METHODS: Twenty infants between 6 to 10 months of age were studied in a tertiary hospital in New Delhi for 48 hours. They were given three semi-solid complementary feeds per day and ad libitum breastfeeding. No other food or fluid was allowed during the study period. A traditional gruel made of rice and pulses with high energy density (oil added; caloric density = 35 kcal/100 g) or low energy density (without oil; caloric density = 20 kcal/100 g) was offered in a randomized manner on consecutive days to all infants. Total caloric intake from breast milk and semi-solids was computed for each day. RESULTS: Infants consumed an equivalent amount of semi-solid (mean difference, 10.75 g/day; 95% confidence interval, 10.56 to 32.06; P = 0.304) and a lower amount of breast milk (mean difference, 121.1 g/day; 95% confidence interval, 35.13 to 207.16; P = 0.008) when high energy density feeds were offered. Although the caloric intake from semi-solids increased significantly (18.9 kcal/day; 95% confidence interval, 12.9 to 24.8; P < 0.001) with the high density diet, the total caloric intake (breast milk and study feeds) decreased (mean difference = 59.6 kcal/day; 95% confidence interval, 5.95 to 113.34; P = 0.031). An inverse relationship was found between caloric density of semi-solids and breast milk intake (r = 0.34, r = 0.12, P = 0.032). CONCLUSION: In the short term, oil supplementation of complementary food in breastfed infants does not translate into enhanced total caloric intake, primarily as a result of breast milk displacement.

Breast Feeding↗
PubMed2005

Exchangeable sodium induced changes in yield, water relation and cation composition of fennel (Foeniculum vulgare Mill).

A pot experiment was conducted with the objectives to assess the adaptation potential of fennel crop grown at 10, 20, 25, 35 and 40 ESP (exchangeable sodium percentage) levels. Results showed that the rate of seed germination, plant growth including branching pattern, umbels per plant and 1000 test seed weight were adversely affected by sodic soils. Assuming that fifty percent reduction in seed yield and Na+/K+ ratio in leaf tissue as an index of alkali tolerance revealed that fennel was tolerant up to 25 ESP. The cell sap pH and EC reflected optimum osmoticum maintenance to withstand sodicity stress at this level and beyond this leaf water potential decreased (negatively) more to impede water uptake.

Biomass↗
PubMed2004

Effect of glucose and light-dark environment on pigmentation profiles in the cyanobacterium Calothrix elenkenii.

Calothrix elenkenii was evaluated for accumulation of chlorophyll, beta-carotene and phycobiliproteins when grown under light-dark cycles and darkness, in the presence of glucose. Highest values of beta-carotene, chlorophyll, proteins and acetylene-reducing activity were recorded when the organism was grown in the presence of glucose under light-dark cycles after 15 d of incubation. The presence of glucose in the medium stimulated pigment production, especially of beta-carotene and chlorophyll, which may be due to increased energy-linked assimilation and ATP production. The photoheterotrophic potential of C. elenkenii can be exploited in value addition for increased and economic production of pigments.

Acetylene↗
PubMed2004

Development of a hybrid delta-endotoxin and its expression in tobacco and cotton for control of a polyphagous pest Spodoptera litura.

A hybrid delta-endotoxin protein was designed against a polyphagous lepidopteran insect pest Spodoptera litura, which is tolerant to most of the known delta-endotoxins. The hybrid delta-endotoxin was created by replacing amino acid residues 530-587 in a poorly active natural Cry1Ea protein, with a highly homologous 70 amino acid region of Cry1Ca in domain III. The truncated delta-endotoxins Cry1Ea, Cry1Ca and the hybrid protein Cry1EC accumulated in Escherichia coli to form inclusion bodies. The solubilised Cry1EC made from E. coli was 4- fold more toxic to the larvae of S. litura than Cry1Ca, the best known delta-endotoxin against Spodoptera sp. None of the two truncated toxins, solubilised from E. coli caused larval mortality. However, trypsinised Cry1Ca protoxin obtained from E. coli and solubilised from inclusion bodies caused mortality of S. litura with LC50 513 ng/ml semi synthetic diet. A synthetic gene coding for the hybrid delta-endotoxin Cry1EC was designed for high level expression in plants, taking into consideration several features found in the highly expressed plant genes. Transgenic, single copy plants of tobacco as well as cotton were developed. The selected lines expressed Cry1EC at 0.1-0.7% of soluble leaf protein. Such plants were completely resistant to S. litura and caused 100% mortality in all stages of larval development. Hence, unlike in E. coli, the hybrid delta-endotoxin folded into a functionally active conformation in both tobacco and cotton leaves. The truncated Cry1EC expressed in tobacco leaves was about 8-fold more toxic (LC50 58 ng/ml diet) compared to expression in E. coli.

Amino Acid Sequence↗
PubMed2004

Increased epithelial uptake of protein antigens in the ileum of Crohn's disease mediated by tumour necrosis factor alpha.

BACKGROUND AND AIMS: The exact nature of the epithelial barrier defect in Crohn's disease remains to be elucidated. Previously we showed increased permeability to proteins in ileal Crohn's disease. Our aims were to study if this barrier defect (a) involves endocytotic uptake of antigens and (b) is related to low grade inflammation not detectable by histology. METHODS: Macroscopically normal segments of distal ileum of Crohn's disease patients (n = 10) were subgrouped into non-inflamed (histologically unaffected) and slightly inflamed tissues and studied in Ussing chambers, with normal ileal specimens from colon cancer patients (n = 9) as controls. Endocytotic uptake into enterocytes of the protein antigen horseradish peroxidase was assessed by measuring the area of horseradish peroxidase containing endosomes in electron photomicrographs. Mucosal tumour necrosis factor alpha (TNF-alpha) mRNA was quantified using real time polymerase chain reaction. For comparison, the effects of low doses of TNF-alpha on endosomal uptake of horseradish peroxidase were studied in cultured T84 cells grown on filter supports. RESULTS: The area of horseradish peroxidase containing endosomes was increased (p<0.001) in enterocytes of non-inflamed ileum of Crohn's disease (2.8 (0.7) mum(2)/300 mum(2)) compared with control ileum (0.6 (0.06)). In non-inflamed mucosa, a significant association between endosomal uptake and mucosal expression of TNF-alpha mRNA (p = 0.03) was found. Low concentrations of TNF-alpha (0.25-1.0 ng/ml) enhanced the endosomal uptake of horseradish peroxidase in polarised T84 cells, without affecting transepithelial electrical resistance. CONCLUSIONS: Our findings suggest increased endosomal uptake of antigens in ileal Crohn's disease that may be mediated by TNF-alpha. These data highlight the transcellular route of antigen uptake in barrier dysfunction and implicate the interaction between epithelial cells and the innate immune system in the development of mucosal inflammation.

Adult↗
PubMed2004

Pain during injection of propofol: the effect of prior administration of ephedrine.

Propofol causes pain on intravenous injection in 28 to 90% of patients. A number of techniques have been tried to minimize propofol-induced pain, with variable results. In a randomized, double-blind, placebo-controlled trial, we compared the efficacy of ephedrine 30 microg/kg pretreatment to lignocaine 40 mg for prevention of propofol-induced pain. Ninety-three adult patients, ASA 1 and 2, undergoing elective laparoscopic cholecystectomy were randomly assigned to three groups of 31 each. Group 1 received normal saline, group 2 received lignocaine 2% (40 mg) and group 3 received 30 microg/kg ephedrine. All pretreatment drugs were made up to 2 ml. Pain at the time of propofol injection was assessed on a four-point scale: 0=no pain, 1 =mild pain, 2=moderate pain, and 3=severe pain. Twenty-seven patients (87%) of ephedrine pretreatment patients had pain during intravenous injection of propofol as compared to 24 (77%) in the normal saline group. In the lignocaine group, propofol-induced pain was observed in only 13 (42%) when compared with other study groups (P<0.05). Pretreatment with ephedrine 30 microg/kg did not attenuate pain associated with intravenous injection of propofol, nor did it improve haemodynamic stability during induction. However, pretreatment with 2% lignocaine (40 mg) was effective in attenuating propofol-associated pain.

Adolescent↗
PubMed2003

Isolation and characterization of an indigenous isolate of Dunaliella sp. for beta-carotene and glycerol production from a hypersaline lake in India.

Dunaliella, a green alga grows in a wide range of marine and freshwater habitats such as oceans, brine lakes, salt marshes and salt-water ditches near the sea, predominantly in water bodies containing more than 10% salt. Sambhar salt lake, Rajasthan (India) was found as one of the natural habitat of Dunaliella sp. The species was isolated and screened for accumulation of beta-carotene and glycerol. It was studied for the growth attributes like total protein, optical density, total chlorophyll, total carotenoid, beta-carotene and glycerol. Under unstressed physico-chemical conditions the maximum beta-carotene and glycerol observed was 1.15 pg/cell and 94.26 pg/cell respectively. The stress (salt stress (NaCl), high light intensities and continuous light) allowed the alga to accumulate high beta-carotene (approximately 4.21 pg/cell under 118.18 micromole m(-2) s(-1) of light intensity) without massive reduction in biomass content. This opens up new avenues for exploring this strain for future research and its commercial exploitation.

Algal Proteins↗
PubMed2003

Evaluation of Tolypothrix germplasm for phycobiliprotein content.

Twenty Tolypothrix strains, including 15 strains of T. tenuis, three strains of T. ceylonica and one strain each of T. nodosa and T. bouteillei, were evaluated for their phycobiliprotein content and composition. Significant differences among the Tolypothrix strains were found at both inter- and intra-specific levels in the production of phycobiliprotein constituents--phycocyanin (PC), allophycocyanin (APC) and phycoerythrin (PE). Four specific parameters, viz. PC or PE content, total phycobiliprotein and total protein content, and percentage of phycobiliproteins, in a mixture of total proteins were used to select four T. tenuis and one T. ceylonica strain as useful for phycobiliproteins production.

Bacterial Proteins↗
PubMed2003

Effect of nutrient depletion on beta-carotene and glycerol accumulation in two strains of Dunaliella sp.

The response of two strains of Dunaliella, a beta-carotene accumulating halotolerant alga, was evaluated under sulphate, nitrate and phosphate limitation. All these factors decreased the growth rate and chlorophyll content but, increased the beta-carotene content of the two isolates of Dunaliella, D1, obtained from GTCC and D2 an indigenous strain isolated from Sambhar salt lake, India. Both the strains exhibited accumulation of beta-carotene and glycerol under the different nutrient limiting conditions. A maximum accumulation of 3.99 pg/cell of beta-carotene was observed under phosphate depletion. However, nutrient depletion did not significantly affect the glycerol accumulation in these cells. D2, the indigenous isolate, was found to be a better accumulator of beta-carotene than D1.

Cells, Cultured↗
PubMed2003

Genetic resistance of Barbari and Jamunapari kids to natural infection with gastrointestinal nematodes.

An investigation was made in 252 Barbari and Jamunapari kids to assess their resistance to natural infection with gastrointestinal (GI) nematodes and to establish indicator traits for such resistance in Indian goats. The indicator traits, faecal egg counts (FEC) and packed cell volume (PCV) were affected by various genetic and non-genetic factors. There were no breed differences in the FEC or PCV at 3, 6 or 9 months of age. Jamunapari male kids had a higher FEC than the female kids at 6 months of age. However, Barbari female kids had a higher FEC than the respective male kids at 9 months of age. At 6 months of age in both breeds, the kids born in the spring (March-April) had a higher FEC than those born in the autumn (October-November). The FEC of kids at 9 months of age was higher than at 3 or 6 months of age. Sire had a significant effect on PCV at 6 and 9 months of age. The kids born in the autumn had a higher PCV than those born in the spring. The PCV of male Barbari kids differed significantly from that of female kids at all the ages. The correlation coefficient of FEC on both body weight and body weight gain was negative, and there was a loss of body weight in the individuals with a high FEC.

Age Factors↗