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G Sridharan

Publications and source records attributed to G Sridharan.

At least 19 recordsLinked to original sources
PubMed1994

Vi-specific latex agglutination for early and rapid detection of Salmonella serotype typhi in blood cultures.

Latex particles coated with rabbit antisera against Salmonella serotype typhi (S. typhi) Vi and O (STO) antigens were used in slide agglutination tests for the rapid identification of S. typhi in blood culture broths as soon as Gram-negative bacilli (GNB) were detected in them. Among 231 consecutive blood cultures showing GNB tested for Vi, and a subset of 163 tested for STO, by latex agglutination (LA), 125 and 32, respectively, were positive. The GNB in 127 blood cultures were confirmed by conventional methods as S. typhi, 125 (98.4%) of which had been identified by the Vi LA test. In the subset of 163, 81 grew S. typhi, of which only 32 (39.5%) had been identified by the STO LA tests. Thus, the sensitivity of the Vi and STO LA tests was 98.4% and 39.5%, respectively, whereas the specificity was 100% for both tests. Of the S. typhi isolates, 38 (30.4%) were detected by the Vi LA test on day 2 and 73 (58.4%) on day 3, day 1 being the date of inoculation of the blood culture broths. Thus, the Vi LA test is suitable for the early and rapid confirmation of S. typhi in blood culture.

Agglutination Tests↗
PubMed1992

Evaluation of modified passive haemagglutination assay for Vi antibody estimation in Salmonella typhi infections.

A simple passive haemmagglutination assay (PHA) was developed to detect Vi antibodies, to improve the diagnosis of typhoid fever by small laboratories. The Vi capsular antigen of Salmonella typhi was extracted by alternate alcohol and acetone precipitation. Formalin fixed, sheep red blood cells treated with chromium chloride were sensitised with this Vi antigen and antibodies detected and measured by PHA. The test had a sensitivity of 83.3% among 30 cases of typhoid fever confirmed by culture. The specificity of the test was 94%, making it suitable for use in laboratories without facilities for IFAT or ELISA.

Antibodies, Bacterial↗
PubMed1992

Salmonella typhi cell wall protein showing antigenic similarity to transferrin.

Antiserum to cell wall proteins of S. typhi showed immunoprecipitin lines of identity with homologous antigen, normal human serum and human transferrin. Also, anti-transferrin antibody showed immunoprecipitin band with S. typhi cell wall proteins and agglutinated S. typhi whole cells, but not Eschericia coli. It is speculated that transferrin or a transferrin-like protein present in the cell wall may play a role in iron-uptake by S. typhi.

Agglutination Tests↗
PubMed1991

Immune response to intradermally injected inactivated poliovirus vaccine.

Immune response to intradermal inoculation of a fractional dose of inactivated poliovirus vaccine (IPV) was measured in 8 adults and 10 children who were previously immune. A striking 4-fold to 1024-fold antibody booster response to all 3 poliovirus serotypes was found in 15 subjects and a similar response to 2 poliovirus serotypes occurred in the other 3 children. Induration and erythema of 3 mm diameter or above, indicative of a cell-mediated immune response, was seen in 12 subjects. Intradermal inoculation of IPV may be a useful technique for secondary immunisation programmes against polio and its use for primary immunisation merits investigation.

Adult↗
PubMed1991

Antigen sharing of Salmonella typhi non-flagellar proteins with other salmonellae and some shigellae and Escherichia coli.

Cathodal moving protein components were identified in agarose gel electrophoresis of the Veronal buffer extract of a non-motile strain of S. typhi (8393, Colindale). Rabbit antiserum was raised against these cationic proteins; it had both agglutinating and precipitating activity. A total of 80 salmonella strains belonging to serogroups A, B, C1, C2, D, E1 and E2 including 26 S. typhi and 10 S. paratyphi A were tested against this antiserum in a slide agglutination test; all strains were agglutinated. Among 94 other bacterial strains tested, the antiserum agglutinated all 16 strains of Shigella flexneri, 2 of 5 Shigella sonnei, 5 of 34 E. coli and 1 of 8 Citrobacter species. These results show that there is antigenic sharing of the non-flagellar proteins of S. typhi with many other salmonellae as well as with some shigellae and E. coli.

Agglutination Tests↗
PubMed1990

Isolation and typing of herpes simplex viruses in the infections of mouth, respiratory and genital tracts.

A total of 60 herpes simplex virus (HSV) isolates obtained from individuals with genital herpes lesions in the mouth or respiratory illness were typed in this study. The HSV isolation rate in genital herpes was 31%. The typing was done by a direct fluorescent monoclonal antibody technique using commercial reagents. All the 60 Vero cell grown isolates were successfully typed without any indeterminate results. Nine isolates were typed as HSV 1 and 51 as HSV 2. The technique was easy to perform and read. HSV 2 was found to predominate in genital infections and HSV 1 in respiratory infections.

Fluorescent Antibody Technique↗
PubMed1990

Sterilization of syringes and needles for immunization programmes using a pressure cooker.

Pressure cookers are being widely used for sterilizing equipment in small clinics and hospitals and under 'field conditions' in developing countries, especially in India. In the literature there is no report on testing of pressure cookers (PC) to determine if they sterilize adequately. The use of PC for a 15-min 'holding time' after steam starts to emanate from under the weight is quite satisfactory by standard efficacy testing methods for autoclaves.

Needles↗
PubMed1989

Epidemiology & clinical profile of genital herpes.

During 1983-86, genital herpes (GH) was diagnosed in 225 (19%) of 1194 patients attending the STD clinic, attached to a Medical College in south India. The patients included 169 men and 56 women; 50 had primary GH and 175 had recurrent GH. The prevalence of GH in men and women did not differ significantly but the proportion of primary GH was significantly higher in women. There was no seasonal variation. The clinical epidemiology of these patients is compared with those in other countries. Virological confirmation of GH was obtained in 38 per cent of patients through culture and in a further 12 percent through serological tests. Papanicolaou smears were positive in 30 per cent men regardless of the type of GH, and in 38.5 and 7.1 per cent women with primary and recurrent GH, respectively. Cultures were positive for herpes simplex virus (HSV) in 38.7 per cent of patients with primary and 38.2 per cent with recurrent GH. Among the 52 viral isolates typed, nine of the 10 isolates from primary GH and all 42 from recurrent GH, were HSV-2. The geometric mean titres of antibody against HSV were higher in patients than in controls.

Adult↗
PubMed1983

Streptococcal antibodies and complement components in tropical post-streptococcal glomerulonephritis.

Anti-deoxyribonuclease "B' was elevated in 94.9% of 59 cases of post-streptococcal glomerulonephritis studied, whereas ASO was elevated only in 54.4% of cases showing that the ADNB titre is a more sensitive indicator of antecedent streptococcal infection than ASO, in tropical countries with a high prevalence of pyoderma. Serum C3c (beta 1A) levels were significantly decreased, especially in the early phase of the illness and returned to normal with remission. C4 levels were decreased only in the early phase of the illness, suggesting involvement of the alternate pathway subsequent to classical pathway activation.

Adolescent↗