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Biomedical subjects

P Kumar

Publications and source records attributed to P Kumar.

At least 775 records · Page 43Linked to original sources
PubMedDate not supplied

Diisopropylphosphorofluoridate-induced depression of compound action potential of frog sciatic nerve in vitro is mediated through the inhibition of cholinesterase activity.

Effect of diisopropylphosphorofluoridate (DFP), an irreversible cholinesterase (ChE) inhibitor, on compound action potential (CAP) of sciatic nerve in vitro was examined. Further, the role of cholinesterase reactivator (1 acetyl-4-hydroxy imino methyl pyridinium bromide; SPK-3) in reversing DFP-induced changes was also evaluated. Diisopropylphosphorofluoridate produced a dose-dependent depression of the CAP. A concentration as low as 0.01 microM DFP produced a 5% depression (P < 0.05) and the maximal depression (30% of control) was observed with 1 microM. The SPK-3 (up to 10 microM) had no effect on the CAP; SPK-3 (10 microM) antagonized the DFP-induced depression of the CAP partially but not after 1 microM DFP. However, the inhibitory concentration of DFP to produce 50% of the maximal depression (IC50) was 0.38 +/- 0.025 microM in the presence of SPK-3 (10 microM; n = 4), against 0.15 +/- 0.05 microM for DFP alone (n = 7). These IC50 values were significantly different (P < 0.05, Student's t-test). The DFP decreased nerve ChE activity by 41% in the absence of SPK-3 and by 31% in the presence of SPK-3. Although SPK-3 could not completely reactivate the inhibited enzyme, it seems reasonable to conclude that the DFP-induced depression of the action potential of sciatic nerve was mediated by inhibiting the ChE activity.

Action Potentials↗
PubMedDate not supplied

Toxicological evaluation of 1-chloroacetophenone and dibenz[b,f]-1,4-oxazepine after repeated inhalation exposure in mice.

Toxicological evaluation was made on the effects of two peripheral sensory irritants (tear gases): 1-chloroacetophenone (CN) and dibenz[b,f]-1,4-oxazepine (CR). Animals had a 15-min daily inhalation exposure to average vapour concentrations of 87.6 mg CN m-3 or 1008 mg CR m-3 (both equal to 0.05 LC50) for 5 or 10 days and were sacrificed 24 h after the last exposure, when biochemical and histopathological observations were made. Both chemicals caused a significant decrease in body weight gain. Histological changes in lung, liver and kidneys were more severe after 10 than after 5 days of exposure and were more severe in CN-exposed than in CR-exposed mice. Organ weight to body weight ratios remained normal except for the spleen to body weight ratio, which decreased in CN-exposed mice after both 5 and 10 days of exposure. Biochemical indicators showed a toxic response only in CN-exposed mice, but the only consistent change was an increase in blood glucose. Hepatic alkaline phosphatase was not influenced, malondialdehyde concentration and acid phosphatase activity were increased only after 5 days of exposure and liver GSH concentration decreased after 10 days of exposure. Results indicate that CN is not only more toxic than CR in absolute terms but is also more toxic at the 5% level of their LC50.

Administration, Inhalation↗
PubMedDate not supplied

Process evaluation of pulse polio immunisation in Delhi.

The aim of the study was to assess the functional aspects and the staffing at Pulse Polio immunisations posts. Interns and medical students conducted the survey in eighty seven pulse polio immunisation posts scattered all over National Capital Territory of Delhi on 18th January 1997. A pre-tested structured format containing information pertaining to dose utilisation and staffing was filled. Number of children given pulse polio was on an average 459.2 per immunisation post (474.7 rural, 516.35 slums and 435.0 urban). Average number of neonates (below one month) per immunisation post given polio drops was 5.1 (1.1%). The break-up for rural area, slums and urban area was 3.0 (0.63%), 6.7 (1.30%) and 4.9 (1.13%) respectively. By 12 pm, 67.8% and by 2 pm 88.7% of the doses had been administered. Staffing at most of the immunisation posts was adequate for all categories of staff except doctors (0.48 per booth).

Developing Countries↗
PubMedDate not supplied

Fluconazole.

Incidence of systemic candidiasis is increasing with improvement in the survival of high risk neonates who undergo multiple interventions. Therapies available to treat systemic fungal infection are few and have several drawbacks. Fluconazole, a new triazole derivative may be a useful anti-fungal agent in view of its excellent oral absorption, easy administration, low plasma protein affinity, long half-life, high concentrations in urine and CSF, minimal adverse reactions, wide spectrum of anti-fungal activity and high specificity for fungal cytochrome P450 system. Its utility in neonates and children with candidiasis has already been documented by few case reports and studies.

Antifungal Agents↗
PubMedDate not supplied

Influence of parental literacy and socio-economic status on infant mortality.

The influence of parental literacy and socio-economic status (SES) on infant mortality rate (IMR) was studied. This report is only a part of much larger community-based prospective study conducted to determine the factors influencing infant mortality in Dakshina Kannada district of Karnataka, by the Department of Community Medicine, Kasturba Medical College, Manipal, with the financial assistance form IDRC, Canada. A total of 12,857 livebirths during the period of October 1, 1991, to September 30, 1992, where registered and followed up for one year. There were 391 infant deaths which gives an IMR of 30.4 per 1,000 livebirths. Univariate analysis and subsequent stepwise multiple logistic regression analysis revealed that, literacy and SES have a very significant role in reducing IMR.

Cause of Death↗
PubMedDate not supplied

Antibiotic associated colitis.

It is a prospective study based on 100 consecutive cases of diarrhea following antibiotic therapy admitted to the pediatric services of J.N. Medical College, A.M.U., Aligarh between January to December 1987. They had C. penicillin (50), chloramphenicol (34), ampicillin (34), gentamicin (34), cephalosporin (4) and cotrimoxazole (4) for 3 days to 3 weeks prior to the onset of diarrhea. Apart from routine and special investigations, naked eye and microscopic examination of stool, its culture for pathogens including Cl. difficile were carried out in all cases. Presence of Cl. difficile cytotoxin was demonstrated by observing the cytopathic. Effect on veru cell culture, 18 grew Cl. difficile (14 cyto toxin positive). Frequency of fever, vomiting, abdominal distension, dehydration and duration of diarrhea was not different (p > 0.05) in the two groups. Purge rate and presence of mucus and blood in Cl. difficile positive patients was significantly higher (p < 0.05). Eight Cl. difficile positive (7 cytotoxin+ve) were subjected to endoscopy. Three of them showed P.M. colitis and 2 non specific colitis. Chloromycetin, gentamicin and penicillin were the main culprits responsible for AAC. None of the patients given ampicillin alone suffered from AAC. The mortality was 5%.

Anti-Bacterial Agents↗
PubMedDate not supplied

Small for gestational age babies: Indian scene.

Intrauterine growth retardation (IUGR) is an important determinant of neonatal mortality, morbidity and poor neurologic outcome. The study was aimed to evaluate the magnitude of perinatal risk factors in causation and the neonatal outcome of small for gestational age (SGA) babies. One hundred and three SGA babies born over a period of one year were retrospectively analysed during their hospital stay. 3.53 per cent of the babies were SGA with mean birth weight of 1657 +/- SD 354 gm (range 600-2200 gm). 68.9 per cent were term babies and 51.5 per cent were females. Toxemia of pregnancy (30.09%), hypertensive diseases of pregnancy (HDP) excluding toxemia (5.8%), diabetes mellitus (1.94%), medical disorders including renal and cardiac (3.88%), anemia (Hb < 8 gm%) and IU infection (0.97%) were the main conditions responsible for SGA. In 56.3% pregnancies, no cause could be ascertained. The common perinatal problems were infections in 27 (26.2%), birth asphyxia in 22 (21.36%), polycythemia in 25 (24.3%), jaundice in 22 (21.36%) and hypoglycemia in 7 (6.8%). Congenital malformations in 2 (1.94%) and Hyaline membrane disease in 1 (0.97%) were uncommon problems. 5.8 per cent babies died due to various perinatal problems. Based on these findings it was concluded that idiopathic (? Constitutional) intrauterine growth retardation was the commonest cause of SGA in Indian babies. 58.3 per cent babies had neonatal problems and they had a better survival compared to their western counterparts.

Causality↗
PubMedDate not supplied

Bone and joint infection in neonates.

A retrospective study was done to review the clinical experience of septic arthritis and osteomyelitis in the newborns in our centre. Case records of all the neonates born from January 1989 to August 1994 and those admitted to outborn nursery from 1985 to 1993 were reviewed. Diagnosis of septic arthritis/osteomyelitis was made in the presence of relevant clinical signs and supported by positive culture from blood or joint fluid and abnormal X-ray or ultrasound findings. The incidence of septic arthritis and osteomyelitis among inborn babies was 1 in 1500. There were 25 neonates with mean gestational age 34.5 (range 27-40) weeks and mean birth weight 2269 (range 990-4750) gms. Limitation of movement (64%) and local swelling (60%) were commonest presentations. A total of 33 joints were involved in 25 babies. Eight babies (32%) had multiple joint involvement. Hip and knee were the most commonly involved joints (48% each). In 19 babies (76%) joint involvement occurred in association with a generalized septicemic illness while 6 babies (24%) had localised signs and symptoms. Joint aspirate was positive for gram stain or culture in 12 (48%) and 10 babies (40%) had positive blood culture. Klebsiella pneumoniae and Staphylococcus aureus were commonest isolates. Radiological changes were seen in 13 (52%) babies. All were treated with appropriate antibiotics and open surgical drainage was done in 5 (20%) cases. Bone and joint infections are important complications in sick septicemic neonates and need early diagnosis, appropriate management with antibiotics, surgical drainage in selected cases to prevent long term morbidity.

Arthritis, Infectious↗
PubMedDate not supplied

The [Ca2+ + Mg2+]-dependent adenosine triphosphatase of SV40 transformed WI38 lung fibroblasts.

The Ca2+-stimulated, Mg2+-dependent ATPase of SV40 transformed WI38 lung fibroblast homogenates exhibits a high affinity for Ca2+ (K0.5 = 0.20 microM) and moderately high affinity for ATP (Km = 28.6 microM) and Mg2+ (K0.5 = 138.5 microM). This activity was NaN3, KCN and oligomycin insensitive but very sensitive to vanadate (I50 = 0.5 microM) suggesting its being neither mitochondrial or microsomal but plasma membrane in origin. Under optimal conditions of protein, hydrogen ion and substrate concentration, 16-19 nmoles phosphate was released per min per mg protein. Hill plot analysis indicated no cooperativity to occur between Ca2+ binding sites. Nucleotides other than ATP and dATP were ineffective as substrates. The trivalent cation, lanthanum (La3+) completely inhibited hydrolysis of ATP at approximately 70 microM (I50 = 25 microM). Calmodulin antagonists trifluoperazine and calmidazolium inhibited ATP hydrolysis in a dose dependent fashion.

Ca(2+) Mg(2+)-ATPase↗