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Biomedical subjects

S Tharavanij

Publications and source records attributed to S Tharavanij.

At least 73 records · Page 4Linked to original sources
PubMed1983

Multiple strains of Plasmodium falciparum are necessary for the growth inhibition assay.

Sixty-seven serum samples from individuals living in a malaria endemic area and sixty sera from healthy blood donors living in Bangkok (non-malarious area) were tested for growth inhibition activity against 3 strains (SO, SN and G-112) of Plasmodium falciparum. Forty-eight percent of the sera from the endemic area were positive when all 3 strains were tested. Among the positive sera, positive rates of 90.6% were observed for the SO and SN strain combination, 87.5% for the SO and G-112 combination, and 50% for the SN and G-112 combination. It is therefore recommended that multiple parasite strains should be tested in the growth inhibition assay. If facilities are limited, a minimum of two strains should be used, one of which is the SO strain or its equivalent.

Animals↗
PubMed1983

Diagnosis of typhoid fever by indirect hemagglutination with lyophilized cells.

An IHA test using stable sensitized red cells was developed for diagnosis of typhoid fever. The antibodies to LPS and CB coated cells were measured in 39 patients with typhoid fever and 79 healthy controls. The diagnostic titer greater than or equal to 1:80 of HA-LPS and Widal reaction; and greater than or equal to 1 : 320 of HA-CB were considered significant. It was found that either IHA or Widal test gave the same degree of sensitivity capable of diagnosing 87.2% of patients with typhoid fever. Antigenicities of lyophilized sensitized cells were retained for at least 6 months of preservation.

Antibodies, Bacterial↗
PubMed1982

Comparison of various serological test results using antigens from different strains of Plasmodium falciparum.

Suitability of different strains of Plasmodium falciparum grown continuously in vitro was compared using the indirect haemagglutination (IHA) the indirect immunofluorescent (IFA) tests and ELISA. In the tests employing soluble antigens (IHA and ELISA), there was a significant higher mean log titer of the same sera tested against different strains. Ranking of the strains in term of sensitivity for the detection of malaria antibody in people in the endemic area were G-112 = SO = CC greater than SU greater than PS in the IHA test and G-112 = SO greater than CC greater than SU greater than PS in the ELISA. The difference in the mean log titers appear to relate neither to the geographical location not the isoenzyme markers tested. There was also an apparent correlation between the results of the IHA and the IFA test but not between these two tests and ELISA.

Enzyme-Linked Immunosorbent Assay↗
PubMed1982

Mouse IgE response to an allergen from Entamoeba histolytica.

Attempts were made to demonstrate the presence of allergenic components in an extract of axenically cultured Entamoeba histolytica (HK 9). Various strains of mice were immunized i.p. with a low dose of the extract mixed with Al(OH)3 and boosted with the same mixture 4 wk later. A high titer of IgE antibody response was demonstrated in BALB/c, DBA/2 (H-2d), CBA (H-2k), and SWM strains but not in C3H/He (H-2k) strain. The extract was fractionated by gel filtration with Sephadex G-200 and then by DEAE-cellulose chromatography with a gradient buffer with progressive increase in molarity. Fractions having the strongest activity to stimulate the IgE antibody response in the mouse were subjected to SDS polyacrylamide gel electrophoresis. From the results of gel filtration and polyacrylamide gel electrophoresis, the molecular weight on the partially purified allergen was estimated to be 25,000 to 27,000 daltons.

Allergens↗
PubMed1982

Infection rates of Cytomegalovirus among Thai pregnant women.

Cervical swabs were collected from 185 pregnant women and urine from 50 healthy non-pregnant women in order to isolate cytomegalovirus by using tissue culture methods. Sera from the mothers and their cord blood were tested for total and classes specific IgM antibodies to cytomegalovirus by using enzyme-linked immunosorbent assay test. CMV was recovered from 8% of pregnant women but none from the non-pregnant women. Seropositive rate for CMV total antibodies and IgM antibodies in pregnant women were 95% and 83% respectively. None of the newborn infants from virus positive mothers had positive CMV-IgM antibodies but one infant from virus-negative mother had IgM antibodies with titre 1:80.

Adolescent↗
PubMed1982

Seasonal variation of entertoxigenic Escherichia coli among children with diarrhoea in Bangkok.

ETEC which produced both LT and ST or LT alone were isolated from 7.4 percent (18/244) of children with diarrhoea treated at two hospitals in Bangkok, Thailand between May 1, 1980 and April 30, 1981. These enteric pathogens were only isolated from children with diarrhoea during the dry and the beginning of the wet season. Eighty-three percent (15/18) children infected with ETEC were infected with antibiotic resistant isolates. One hundred percent of LT + ST + E. coli and 76 percent (50/66) of LT + ST - E. coli were resistant to two or more antibiotics. Fourteen of 15 (93%) ETEC transferred antibiotic resistance and nine of 14 (64%) isolates which transferred resistance in bacterial conjugation experiments also transferred toxigenicity. This experience suggests that the widespread use of antibiotics in Thailand could increase the prevalence of antibiotic resistant enterotoxigenic bacteria.

Anti-Bacterial Agents↗
PubMed1982

Anti-P1, allohemagglutinins associated with Clonorchis sinensis and opisthorchis viverrini infections in patients from Southeast Asia.

An automated assay of anti-P1 allohemagglutinins has been carried out on sera of 61 individuals from Southeast Asia : 28 with clonorchiasis, 18 with opisthorchiasis and 15 control subjects. Anti-P1 activity was detected in 61% of the opisthorchiasis sera, 57% of the clonorchiasis sera and in 26.6% of the control subjects. Their concentration, in the sera, was low in control subjects and exceptionally high in clonorchiasis and opisthorchiasis (up to 13 and 22 times the maximum concentration of the control subjects, respectively). In all cases the anti-P1 antibodies were of IgM class. The results suggested that Clonorchis and Opisthorchis were responsible for immunization of the patients, with P1 alloantigen.

Blood Group Antigens↗
PubMed1981

Cellulose acetate membrane precipitin (CAP)test in amoebiasis using antigens from four different strains of Entamoeba histolytica.

A simple cellulose acetate membrane precipitin (CAP) test was evaluated against immunoelectrophoresis (IEP) test using saline extract from 4 different strains (HK-9, HT-10, HT-12 and HT-31) of axenically grown Entamoeba histolytica as the antigens. All 81 sera from patients with amoebic liver abscess were positive in the IEP against the antigens from all 4 strains. With the CAP test the number positive against antigens from HK-9, HT-10, HT-12 and HT-31 were 79,77,79 and 71 respectively Sera from 100 blood donors were negative by both IEP and CAP tests against antigens from all 4 strains. Comparison between the number of precipitating bands demonstrated by either IEP or CAP test showed that strain HT-12 was the best source of antigen in exhibiting significantly more number of precipitating bands, strain HT-31 was the poorest. The strain HT-10 was comparatively superior to strain HT-31 in the CAP test whereas in the IEP test strain HK-9 and HT-31 were both inferior to strain HT-10.

Antigens, Viral↗
PubMed1981

Herpes simplex virus in patients with aphthous ulcers in Bangkok.

Fifty-two paired sera and 40 single sera and swabs from the aphthous like ulcers of the tongue, gum, and buccal mucosa were collected from patients at a private clinic and from workers of canned fish packaging company in an attempt to isolate herpes simplex virus. Sixty-eight percent had positive HVH isolation with high ELISA antibody titers. Among 52 paired sera from patients, 68.4% had recurrent infections and 31.6% had primary infection.

Adolescent↗
PubMed1981

Immunological study of typhoid fever in man. II Cell-mediated immune response.

The development of cell-mediated immune response to lipopolysaccharide and Barber protein from Salmonella typhi was investigated in patients suffering from typhoid fever. The cell-mediated immunity as measured by the leukocyte adherence inhibition test, was demonstrable in 77% of patients with typhoid fever but only in 5.6% of healthy controls. It was found that cell-mediated immune response appeared after the first week of illness and persisted for at least 4 weeks. The time course development of cell-mediated immune response and humoral immune response was correlated but the magnitude of each response was independent on one another.

Histocompatibility Antigens Class II↗
PubMed1981

Simultaneous preparation of merozoites and concentrated schizonts of Plasmodium falciparum.

A technique has been described for a simultaneous preparation of merozoites and concentrated schizonts. The merozoites were harvested after high speed centrifugation of either the supernatant of the low speed centrifugation of the Plasmodium culture or the portion floated in physiogel. The concentrated schizonts were prepared by physiogel floatation technique followed by differential centrifugation in 50% percoll. An average of 56% of parasitized red cells were obtained, of which 64% were schizonts. Concentration of trophozoites and schizonts was 9.5 fold.

Culture Media↗
PubMed1981

Leucocyte migration agarose test to study cell-mediated immunity in amoebiasis.

The leucocyte migration agarose test (LMAT) was used to measure quantitatively the magnitude of cell-mediated immunity (CMI) in 35 patients with amoebic liver abscess and 22 healthy controls. LMAT was positive in 65.7% and 85.7% of patients with amoebiasis in the presence of 200 microgram and 400 microgram of the amoeba extract respectively, whereas the test in all 22 healthy controls was negative. Time course studies showed that within 10 days after the onset of clinical illness, only 1 of 4 patients was positive. Thereafter the percentage positivity was raised, especially when 400 microgram antigen was used. Maximum CMI response was apparent between 31-60 days after the onset of clinical illness. The indirect haemagglutination (IHA) test showed that all patients and 5 of 22 healthy controls were positive. These was no correlation between IHA titers and the magnitude of LMAT reaction.

Antibody Formation↗