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P B Kulkarni

Publications and source records attributed to P B Kulkarni.

16 recordsLinked to original sources
PubMed2005

Studies on salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA): potential energetic ballistic modifiers.

The Co/Cu/Ni/Fe salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA) were prepared and characterized during this work. All the salts exhibited exothermic decomposition in DSC. The FT-IR spectra of the gaseous products evolved during TGA of NTO salts indicated the release of NO2 and cleavage of NTO ring during the course of decomposition. Thermal decomposition of TABA salts also produced NO2 on decomposition. The transition metal salts enhanced the burning rates of AP-HTPB composite propellant evaluated during this work. The best catalytic effect was obtained with Fe-NTO salt which increased the burning rate to the extent of approximately 80% as well as brought down the pressure index (n) to 0.18 (2-9MPa).

Aniline Compounds↗
PubMed2005

Synthesis, characterization, thermolysis and performance evaluation studies on alkali metal salts of TABA and NTO.

The lithium (Li) and potassium (K) salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA) were prepared and characterized during this work. The synthesis was carried out by addition of a solution of lithium/potassium hydroxide to the aqueous solution of NTO and TABA, respectively. The products were characterized by elemental analysis, metal content determination and Fourier Transform Infrared (FTIR) Spectrum. Differential scanning calorimetry (DSC) profile indicated that Li and K salts of NTO and TABA undergo exothermic decomposition in the temperature range of 257-360 degrees C suggesting their energetic nature. The thermo gravimetric (TG) weight loss pattern revealed loss of water for Li/K salts of NTO and TABA in the temperature range of 115-155 degrees C. Sensitivity results revealed that the compounds are insensitive to impact and friction (impact sensitivity--height of 50% explosion>170 cm and friction insensitivity up to 36 kg) stimuli despite even the parent molecule of NTO salts (NTO) being HEM in the hazard category of 1.1. The FTIR spectra of the gaseous products evolved during TGA of NTO and TABA salts indicated the release of NO2. The formation of products such as LiNCO and KNCO was also observed in case of NTO salts, whereas that of CO2 and NH containing products was indicated in case of TABA salts during this study. In order to assess the performance as energetic ballistic modifiers (EBMs), NTO and TABA salts were incorporated in the ammonium perchlorate-hydroxyl terminated polybutadiene (AP-HTPB) composite propellants. The potassium salts enhanced the burning rate of the propellant. The best catalytic effect was obtained with K-TABA salt, which increased the burning rate to the extent of approximately 81% as well as brought down the n-value to 0.15 (pressure 2-9 MPa).

Aniline Compounds↗
PubMed2005

Influenza surveillance in Pune, India, 2003.

Influenza surveillance was conducted in Pune, India in 2003. A total of 573 throat swabs/ nasal swabs (TS/NS) and 190 nasopharyngeal aspirates (NPA) were collected from 763 in- and out-patients who were mostly children aged 0-16 years. TS/NS (507/573) and NPA (42/190) specimens were processed in MDCK cell cultures and identified with the hemagglutination inhibition test (HI). A total of 37 influenza viruses was isolated: twenty-three type A (H3N2) and 14 type B of the Yamagata lineage were isolated from 29 children and 8 adults. Three type A (H3N2) isolates were characterized as being similar to A/Panama/2007/99 like, A/Korea/770/2000 like, and B/Sichuan/379/99 like strains.

Child↗
PubMed2001

Seroepidemiology of influenza in Pune, India.

BACKGROUND & OBJECTIVES: Influenza viruses cause frequent epidemics and periodic pandemics throughout the world due to antigenic variations. Serological data can be useful to determine the disease burden and population immunity and for predicting the likelihood of occurrence and potential severity of subsequent epidemics. We undertook a serological analysis of antibodies against ten influenza virus strains in Pune, India. METHODS: Haemagglutination inhibition (HI) test was done on 619 sera collected between 1997-99 during an age-stratified serosurvey in Pune, India against 10 strains of influenza virus. Overall prevalence and spectrum of HI antibodies against these strains was determined. RESULTS: Antibodies to at least one influenza virus strain was seen in 62 per cent (116/188) of the sera from individuals in the age group 5-15 yr, 77 per cent (85/111) in sera from 16-25 yr, 78 per cent (93/119) from 26-35 yr, 84 per cent (77/92) from 36-45 yr and 93 per cent (101/109) in sera from individuals aged > 45 yr. The antibody spectrum progressively increased with age. Antibodies to the pandemic strain A(H2N2) were absent in the age groups < 25 yr. INTERPRETATION & CONCLUSION: The results indicate that influenza virus infection occurs in a large proportion of individuals in our community and may be responsible for a considerable amount of morbidity and mortality. The study also demonstrates the absence of antibody to A/Singapore/1/57 (H2N2) strain in younger persons < 25 yr of age. The potential of its reintroduction cannot be ruled out as H2 variants are circulating in wild birds and population immunity in humans is decreasing.

Adolescent↗
PubMed1998

Does beta-carotene protect membrane lipids from nitrogen dioxide?

Lipid peroxidation in rat liver microsomes, induced by nitrogen dioxide (NO2), a free radical toxin, was examined in the absence and in the presence of varying concentrations of beta-carotene. The extent of peroxidation was assayed by determining the malonaldehyde formed as thiobarbituric acid reactive substances (TBARS). When the concentration of beta-carotene was 13.8 and 43.1 nmol/mg protein, no protection was seen, rather an increase of 10% and 30%, respectively, in TBARS was observed as compared with the normal microsomes containing no beta-carotene. However, at beta-carotene concentrations of 66.5 and 89.4 nmol/mg protein, only a marginal increase of 9% and 4% in TBARS, respectively, was observed. The amount of beta-carotene consumed during peroxidation, determined by following the absorbance at 450 nm, was found to increase linearly with increased exposure to NO2. The direct reaction of NO2 with beta-carotene was studied in an inert organic solvent, acetonitrile, by following the absorption spectrum of beta-carotene in the wavelength region 220-600 nm. The rate of loss of beta-carotene was found to be much faster than that in microsomes. The results suggest that in in vitro systems, the reaction of secondary lipid-derived radicals with beta-carotene and their relative competition for NO2 plays an important role in the actual function of beta-carotene as a prooxidant or an antioxidant. Another lipid soluble antioxidant, alpha-tocopherol (vitamin-E), showed significant protection against NO2-induced lipid peroxidation at a concentration of 45 nmol/mg protein under these conditions.

Animals↗
PubMed1984

Rickets in premature infants fed different formulas.

To study the role of formula as a cause of rickets, we randomly assigned 46 very-low-birth-weight (VLBW) infants (less than or equal to 1,500 gm) to one of three groups receiving either Isomil, a soy isolate formula, Similac with Iron, a common milk-based formula, or Similac 24 LBW, a hypercaloric milk-based formula designed for low-birth-weight infants during the first three to four months of life. Postnatal changes in serum calcium, phosphorus, alkaline phosphatase, and albumin were monitored during this study. Radiologic diagnosis of rickets was made in 60% of infants fed Isomil and 5% fed Similac with Iron. Significantly low levels of serum phosphorus and high levels of serum alkaline phosphatase were also seen in infants fed Isomil. The exact cause of the biochemical changes and the high incidence of rickets among infants fed Isomil is not clear. Poor solubility and possibly the decreased bioavailability of minerals in soy isolate formula may be important. We conclude that rickets occurs with high frequency among VLBW infants fed soy isolate, but not milk-based formulas. We suggest that prolonged feeding of soy isolate formulas should be avoided in VLBW infants.

Alkaline Phosphatase↗
PubMed1980

Cerebrospinal fluid lactate dehydrogenase in infants with perinatal asphyxia.

Cerebrospinal fluid (CSF) lactate dehydrogenase was determined in 19 control infants without asphyxia (Group I), 24 infants with perinatal asphyxia (Group II), and 26 asphyxiated infants with seizures (Group III). Mean birthweights, gestational ages, CSF glucose, protein and red blood cells, and the ages at which the lumbar punctures were performed were not significantly different among the three groups. Mean CSF lactate dehydrogenase was significantly higher in Group III than in Groups I and II. Isoenzyme patterns indicated that the origin of the CSF lactate dehydrogenase was neuronal tissue, or a plasma transudate from increased permeability of the blood-brain barrier. There were 10 deaths due to anoxic encephalopathy in Group III, but none in Groups I or II. Follow-up of survivors at 10 to 30 months of age revealed neurological sequelae in three infants in Group I, two in Group II and five in Group III. Mean CSF lactate dehydrogenase in those with sequelae had not been significantly different from that of normal survivors; however, the mean was significantly higher in infants who died with anoxic encephalopathy compared with normal infants. These data indicate that CSF lactate dehydrogenase is significantly elevated in infants with fatal anoxic brain damage, and suggest that determinations may be of prognostic value in non-fatal cerebral hypoxia.

Asphyxia Neonatorum↗
PubMed1977

Cholangiocarcinoma associated with biliary cirrhosis due to congenital biliary atresia.

An 11-year-old girl developed cholangiocellular carcinoma in association with biliary cirrhosis due to congenital biliary atresia. An exploratory laparotomy and an operative cholangiogram at 3 months of age had confirmed the diagnosis of extrahepatic biliary atresia. A liver biopsy specimen taken at 6 months of age showed biliary cirrhosis. The subsequent clinical course was characterized by persistent moderate jaundice, anemia, malnutrition, rickets, pathologic fractures, and recurrent gastrointestinal bleeding. The presence of cholangiocellular carcinoma of the liver with advanced biliary cirrhosis was established at an exploratory laparotomy a week before her death. We discuss here the pathogenesis of biliary cirrhosis and carcinoma of the liver; there may be a relation between the two in the childhood population.

Adenoma, Bile Duct↗