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Biomedical subjects

R K Kaushal

Publications and source records attributed to R K Kaushal.

At least 19 recordsLinked to original sources
PubMed2006

Purification of a moderate thermotolerant Bacillus coagulans BTS1 lipase and its properties in a hydro-gel system.

An alkaline thermotolerant lipase of Bacillus coagulans BTS1 was successively purified by ammonium sulfate precipitation and DEAE anion exchange chromatography. The purified lipase immobilized in alginate beads showed an optimal activity at pH 7.5 and 55 degrees C. A pH of 5.0 or 10.0 completely quenched the activity of immobilized lipase. The alginate-bound lipase retained its activity following exposure to most of the organic solvents including amines, alkanes and alcohols. Chloride salt of Al3+, Co2+, Mg2+ and NH4+ modulated the lipase activity of alginate-immobilized enzyme. The alginate entrapped lipase showed a preferentially high activity towards p-nitrophenyl palmitate (C: 16) and activity of matrix increased following exposure to SDS. Moreover, the immobilized lipase retained more than 50% of its activity after 3rd cycle of reuse.

Alcohols↗
PubMed2006

Enhancement of ethyl propionate synthesis by poly (AAc-co-HPMA-cl-MBAm)-immobilized Pseudomonas aeruginosa MTCC-4713, exposed to Hg2+ and NH4+ ions.

A purified alkaline thermo-tolerant bacterial lipase from Pseudomonas aeruginosa MTCC-4713 was immobilized on a poly (AAc-co-HPMA-cl-MBAm) hydrogel. The hydrogel-bound lipase achieved 93.6% esterification of ethanol and propionic acid (300 mM: 100 mM) into ethyl propionate at temperature 65 degrees C in 3 h in the presence of a molecular sieve (3 angstroms). In contrast, hydrogel-immobilized lipase pre-exposed to 5 mM of HgCl2 orNH4Cl resulted in approximately 97% conversion of reactants in 3 h into ethyl propionate under identical conditions. The salt-exposed hydrogel was relatively more efficient in repetitive esterification than the hydrogel-bound lipase not exposed to any of the cations. Moreover, bound lipase exposed Hg2+ or NH4+ ions showed altered specificity towards p-nitrophenyl esters and was more hydrolytic towards higher C-chain p-nitrophenyl esters (p-nitrophenyl laurate and p-nitrophenyl palmitate with C 12 and C 16 chain) than the immobilized lipase not exposed to any of the salts. The later showed greater specificity towards p-nitrophenyl caprylate (C 8).

Acrylamides↗
PubMed2005

Purification and properties of a novel extra-cellular thermotolerant metallolipase of Bacillus coagulans MTCC-6375 isolate.

A novel extra-cellular lipase from Bacillus coagulans MTCC-6375 was purified 76.4-fold by DEAE anion exchange and Octyl Sepharose chromatography. The purified enzyme was found to be electrophoretically pure by denaturing gel electrophoresis and possessed a molecular mass of approximately 103 kDa. The lipase was optimally active at 45 degrees C and retained approximately 50% of its original activity after 20 min of incubation at 55 degrees C. The enzyme was optimally active at pH 8.5. Mg2+, Cu2+, Ca2+, Hg2+, Al3+, and Fe3+ at 1mM enhanced hydrolytic activity of the lipase. Interestingly, Hg2+ ions resulted in a maximal increase in lipase activity but Zn2+ and Co2+ ions showed an antagonistic effect on this enzyme. EDTA at 150 mM concentration inhibited the activity of lipase but Hg2+ or Al3+ (10mM) restored most of the activity of EDTA-quenched lipase. Phenyl methyl sulfonyl fluoride (PMSF, 15 mM) decreased 98% of original activity of lipase. The lipase was more specific to p-nitrophenyl esters of 8 (pNPC) and 16 (pNPP) carbon chain length esters. The lipase had a Vmax and Km of 0.44 mmol mg(-1)min(-1) and 28 mM for hydrolysis of pNPP, and 0.7 mmol mg(-1)min(-1) and 32 mM for hydrolysis of pNPC, respectively.

Bacillus↗
PubMed2005

Pansinusitis due to Sporothrix schenckii.

Summary A case of mucocutaneous sporotrichosis presenting as mycotic pansinusitis with polyposis with intracranial and intraorbital extension in a patient from Punjab, India is described. The patient had nasal discharge, sneezing and nasal obstruction for 12 years, had undergone repeated surgeries (for endoscopic clearance) but had recurrence. Computerized tomography (CT) and magnetic resonance imaging (MRI) findings revealed pansinusitis. A definitive diagnosis of sporotrichosis was established by culture of Sporothrix schenckii, verification of its dimorphic character and a positive pathogenicity test. The patient was successfully treated with potassium iodide and itraconazole.

Adult↗
PubMed2005

Transcutaneous bilirubinometer in assessment of neonatal jaundice in northern India.

This study was undertaken from April 2002 to March 2003 to find out the correlation of transcutaneous bilirubinometer index with serum bilirubin levels in term, pre-term, small for gestation age babies, with and without phototherapy in neonates with jaundice. Another aim was to evaluate the transcutaneous bilirubinometer as a screening device for neonatal hyperbilirubinemia by finding the action levels for TcBI at forehead and sternum at which sample for serum bilirubin estimation should be taken. A total of 104 neonates were evaluated. Mean (SD) age (hours), birth weight (grams) and gestational age (weeks) were 100.4 (37.90), 2264.9 (634.4) and 36.8 (2.9) respectively. Mean serum bilirubin was 16.6 (6) mg/dL. Overall a correlation coefficient of 0.878 at forehead and 0.859 at sternum was observed. On excluding infants receiving phototherapy coefficients of 0.900 at forehead and 0.908 at sternum were noted. Correlation coefficient over forehead and sternum was found to drop from 0.85 to as low as 0.33 with duration of phototherapy exceeding 48 hrs. Lastly the determined action levels had a sensitivity of 77.8 to 100 % in assessing the need for serum bilirubin estimation in various groups.

Administration, Cutaneous↗
PubMed2004

Properties of an immobilized lipase of Bacillus coagulans BTS-1.

Lipase (EC 3.1.1.3) is a tri-acylglycerol ester hydrolase, catalysing the hydrolysis of tri-, di-, and mono-acylglycerols to glycerol and fatty acids. To study the effect of adsorption of a lipase obtained from Bacillus coagulans BTS-1, its lipase was immobilized on native and activated (alkylated) matrices, i.e. silica and celite. The effect of pH, temperature, detergents, substrates, alcohols, organic solvent etc. on the stability of the immobilized enzyme was evaluated. The gluteraldahyde or formaldehyde (at 1% and 2% concentration, v/v) activated matrix was exposed to the Tris buffered lipase. The enzyme was adsorbed/entrapped more rapidly on to the activated silica than on the activated celite. The immobilized lipase showed optimal activity at 50 degrees C following one-hour incubation. The lipase was specifically more hydrolytic to the medium C-length ester (p-nitro phenyl caprylate than p-nitro phenyl laurate). The immobilization/entrapment enhanced the stability of the lipase at a relatively higher temperature (50 degrees C) and also promoted enzyme activity at an acidic pH (pH 5.5). Moreover, the immobilized lipase was quite resistant to the denaturing effect of SDS.

Bacillus↗
PubMed2003

Role of C-reactive protein in deciding duration of antibiotic therapy in neonatal septicemia.

In this study serum C-reactive protein (CRP) levels were used to evaluate the duration of antibiotic therapy in 50 consecutive neonates with suspected septicemia. In 44 percent of cases therapy was stopped on 3rd day, as CRP was normal. In 8 percent antibiotics could be stopped within 5-7 days as CRP values returned to normal and in 48 percent therapy was extended beyond 7th day, as CRP values were high or rising persistently. Negative predictive value of serial CRP was 100 percent in deciding duration of antibiotic therapy in suspected neonatal septicemia up to 7 days. The correlation between positive CRP, raised micro ESR and positive blood culture was significant (p < 0.005).

C-Reactive Protein↗
PubMed2000

Risk of seizures and neurocysticercosis in household family contacts of children with single enhancing lesions.

A small, single enhancing lesion (SEL) is often noted upon computed tomography (CT) in children and young adults with recent focal or generalized seizures. A high frequency of seizures has been reported in family members of persons with SEL. We studied the prevalence of seizures and cysticercus electro-immuno-transfer blot (EITB) based seropositivity among family members, specifically household family contacts of pediatric subjects with a SEL. An attempt was also made to determine the etiology of seizures in household family contacts using magnetic resonance imaging (MRI). Information regarding seizure semiology, personal and food habits and detailed family pedigrees was obtained from 20 consecutive pediatric subjects with a SEL and 51 of their household family contacts. EITB sero-assays and stool examinations were performed on all participating subjects. MRIs were done on all EITB positive household family contacts. A family history of seizures was obtained in six index children (30%) (five household first-degree relatives and two distant relatives). Seventeen index children (85%) and 14 family contacts (27%) were EITB positive. A tendency towards clustering of EITB positive cases within individual families was observed. Stool examinations did not reveal Taenia species ova in any of EITB positive subjects. Neuroimaging studies revealed abnormalities consistent with active or inactive neurocysticercosis in all five household family contacts with history of seizures. Four of these five subjects were EITB positive and one was EITB negative. We concluded that children with SEL and seizures may have a family history of seizures. There is a high seropositivity rate in household family contacts of pediatric subjects with solitary cysticercus granulomas (SCGs). EITB based seropositivity in household family contacts with seizures, strongly predicts a cysticercal etiology for seizures. It may be worthwhile to screen household family contacts of children with SEL for taeniasis-cysticercosis.

Cerebral Cortex↗
PubMed2000

Childhood trichobezoar.

Two cases of trichobezoar with unusual presentation in rural female children are described. The first one in a healthy asymptomatic child with no abnormal psychological behaviour and other one in an emotionally disturbed child with history of trichotillomania. Both were treated surgically with no recurrence. A physical sign of indentibility is discussed and literature is also reviewed.

Bezoars↗
PubMed1999

Cysticercus immunoblot assay in patients with single, small enhancing lesions and multilesional neurocysticercosis.

A single, small (< 20 mm), ring or disc shaped contrast enhancing lesion located at the cortical-subcortical junction with minimal or no surrounding edema on computed tomography is the commonest mode of presentation of neurocysticercosis in the Indian subcontinent. Serum samples of 37 patients with these single, small enhancing lesions (SSEL's) and five patients with typical multilesional parenchymal neurocysticercosis were tested by the electro-immunoblot transfer (EITB) assay and the enzyme linked immunosorbent assay (ELISA). EITB was positive in 18 patients (48.64%) and ELISA was positive in 21 patients (56.76%) with SSEL's. On the other hand EITB was positive in all five patients (100%) and ELISA was positive in four patients (80%) with multilesional neurocysticercosis. The low sensitivity of the EITB in the SSEL's is probably linked to an insufficient immune stimulation provided by a single cysticercus cyst.

Humans↗