Biomedical subjects

R Jayakumar

Publications and source records attributed to R Jayakumar.

61 records · Page 4Linked to original sources

PubMed1992

Outcome prediction in early management of severe head injury: an experience in Malaysia.

The outcome of 109 patients with severe head injury was studied in relation to clinical and computed tomographic (CT) criteria on admission, after resuscitation. Age, Glasgow Coma Score (GCS) and state of pupils strongly correlated with outcome. The presence of hypothalamic disturbances, hypoxia and hypotension were associated with an adverse outcome. The CT indicators associated with poor outcome were perimesencephalic cistern (PMC) obliteration, subarachnoid haemorrhage, diffuse axonal injury and acute subdural haematoma. The prognostic value of midline shift and mass effect were influenced by concomitant presence of diffuse brain injury. For the subset of patients aged < 20 years, with GCS 6-8 and patent PMC (n = 21), 71.4% correct predictions were made for a good outcome. For the subset of patients aged > 20 years, with GCS 3-5 and partial or complete obliteration of PMC (n = 28), 89.3% correct predictions were made for a poor outcome.

Adolescent↗

PubMed1992

C9 conformation of N-(N alpha-[(tert.-butyloxy)-carbonyl]-L-alanyl)-N,N'-dicyclohexylu rea in solid and solution.

An X-ray diffraction study was carried out on a single crystal of N-(N alpha-[(tert.-butyloxy)-carbonyl]-L-alanyl)-N,N'-dicyclohexylur ea belonging to the tetragonal space group P4(1)2(1)2, having cell dimensions a = b = 10.102(3) A, c = 46.067(7) A, V = 4701.2 A3, Z = 8. The crystal structure was solved by direct methods and refined to an R value of 0.056 for 1602 unique reflections with I greater than 2.5 sigma(I). Crystal structure analysis shows the presence of an intramolecular N-H ... O=C H-bond stabilizing the molecule in a folded form similar to that of a beta turn, forming a nine-membered ring. IR and 1H-NMR studies in CDCl3 solution confirm the stable folded conformation found in the crystalline state, as well as the existence of N-H ... O=C H-bonds in the title compound, as in peptides.

Alanine↗

PubMed1991

Immunoglobulin response to rabies virus immunization in dogs.

Nondescript dogs were inoculated with betapropiolactone-inactivated 5% sheep brain antirabies vaccine. The antibody response was found to show more IgM (19S) initially and more IgG (7S) latterly. A local strain of street rabies virus was used for postvaccinal challenge. The correlation between immunoglobulin response and protection were discussed.

Animals↗

PubMed1990

Studies on cell-mediated immune response to rabies virus immunization in dogs.

Peripheral blood leucocytes (PBL) from unvaccinated dogs and dogs vaccinated subcutaneously with beta-propiolactone (BPL) inactivated sheep brain antirabies vaccine were exposed in vitro to rabies antigen. A direct leucocyte migration inhibition (LMI) assay in agarose was used to study the cell-mediated immune (CMI) response. The CMI response could be detected as early as 7 days postvaccination. It reached a peak by 14 days postvaccination followed by a decline. The PBL from unvaccinated control dogs were not stimulated by rabies virus antigen.

Animals↗

PubMed1989

Comparison of enzyme immunodiagnosis with immunofluorescence for rapid diagnosis of rabies in dogs.

A comparison between Direct Immunofluorescence Test (FAT) and Rapid Rabies Enzyme Immunodiagnosis test (RREID) was made to detect rabies viral antigens from the brain and salivary gland tissues of experimentally infected and in rabies suspected dogs. Both the tests presented an efficiency level of 100 per cent and both are equally sensitive.

Animals↗

PubMedDate not supplied

Calix[8]arene-mediated self-assembly of tetrapeptide H-Leu-Leu-Ile-Leu-OMe.

Conformational analysis of peptide 1, H-Leu-Leu-Ile-Leu-OMe on complexing with macro cycle calix[8]arene has been carried out using (1)H-NMR and FTIR spectroscopic techniques. Stoichiometry of the complex formed in the 1:8 ratio was evidenced by a Job plot. NMR studies of the above peptide show a marked downfield shift and an increase in (3)J values for NH resonances on complexing with calix[8]arene. The characteristic NOE connectivity between N(i+1)H and C(ialpha)H confirm beta-sheet conformation in the complexed state. Both (1)H-NMR and FTIR results indicate that the alpha-amino group of Leu I is proximal to the macrocycle and is involved in hydrogen bond formation with phenolic hydrogen atom of the calix[8]arene. This suggests that calix[8]arene provides a suitable platform for peptide 1 to self-assemble in a parallel beta-sheet conformation. The nature of calix[8]arene interaction with peptide 1 has been studied using dynamic NMR studies, which concludes that a bifurcated hydrogen bonding interaction exists in the molecular interfaces of the assembly.

Calixarenes↗

PubMedDate not supplied

Rapid Dot enzyme immuno assay for the quantitation of rabies antibodies.

A rapid dot enzyme immuno assay (Dot ELISA) for rabies antibody estimation has been standardized in which nitrocellulose sheet has been used as a solid support absorbing a commercial tissue culture rabies vaccine as antigen. The test was compared with a standard plate ELISA test. The results were comparable and the student "t' test for proportion revealed that plate ELISA test is significantly better (P 0.05) when compared to Dot ELISA for the number of sera with titre < 0.5 Iu/ml and in the case of > 0.5 IU/ml Dot ELISA is found to be better over plate ELISA test at the same significance level.

Adolescent↗