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S Devi

Publications and source records attributed to S Devi.

At least 19 recordsLinked to original sources
PubMed2003

In vitro demonstration of the hemolytic, cytotoxic activities and induction of apoptosis in Orientia tsutsugamushi infected L929 mouse fibroblast cells.

Using cultured mouse fibroblast L929 cells, this study demonstrated the hemolytic and cytotoxic activities and induction of apoptosis in cells infected with Orientia tsutsugamushi. Low levels of hemolytic activity were detected using heavily infected cells. No hemolysin or cytotoxin were detected in the infected culture fluid regardless of the pathogenicity of the O. tsutsugamushi strains in mice. Using propidium iodide uptake assay, acridine orange/ethidium bromide staining and terminal deoxynucleotide transferase-mediated dUTP-digoxigenin nick-end labeling assay, apoptosis was observed in L929 cells infected with Karp and Gilliam strains.

Animals↗
PubMed2002

Expression of recombinant proteins of Orientia tsutsugamushi and their applications in the serodiagnosis of scrub typhus.

In this study, recombinant proteins that encompassed the AD I-AD III regions of 56 kDa immunodominant gene of 2 Orientia tsutsugamushi (OT) serotypes; Gilliam and TA763 were expressed in Escherichia coli. Both recombinant proteins exhibited serologic cross-reactivity with the rabbit antisera against various OT serotypes, as evaluated by enzyme-linked immunosorbent assay (ELISA), but not against other rickettsial species, including Rickettsia typhi, R. prowazekii and TT118 SFG rickettsiae. The feasibility of using the recombinant proteins as a diagnostic reagent was further evaluated by ELISA using sera from blood donors and scrub typhus patients. The results suggested a higher affinity of the antihuman IgM than IgG with both recombinant proteins. The IgM ELISA findings were agreeable with the results of indirect immunoperoxidase (IIP) assay especially with sera of high antibody (1:1600). However, more than one antigen are probably needed for development of an effective assay for serodiagnosis of scrub typhus in endemic areas.

Animals↗
PubMed2002

Typhoid fever in Kuala Lumpur and a comparative evaluation of two commercial diagnostic kits for the detection of antibodies to Salmonella typhi.

The aim of this study was to compare two commercial kits, theTyphidot and the PanBio ELISA with the present Widal test. Demographic data for all serodiagnosed cases for the years 1991-1998 were collected. From this data, 144 were selected as samples for comparative evaluation of the commercial kits. Fifty sera were culture positive for Salmonella typhi, 50 were culture negative but clinically diagnosed as typhoid fever and Widal positive and 44 were serodiagnosed as enteric of which 21 were culture positive for other Salmonella species, 20 were serodiagnosed for other febrile illnesses and three sera culture positive for other species of enterobacteriaceae. The specificity, sensitivity and efficiency of the tests were calculated with the positive culture for S. typhi as the gold standard. Sensitivity, specificity and efficiency of test for Typhidot and Typhidot M kits were 98%, 76.6% and 84.0% and PanBio ELISA were 78%, 80% and 79.9%. The two commercial kits evaluated were found to be less time consuming and easier to perform than Widal. The Typhidot M seems to be a practical alternative in the field and in small hospitals with lesser facilities.

Agglutination Tests↗
PubMed2002

Antigenic types of Orientia tsutsugamushi in Malaysia.

The seroprevalence of various Orientia tsutsugamushi (OT) strains among Malaysian patients with suspected scrub typhus infections was determined using an indirect immunoperoxidase (IIP) assay. IgG against a single OT strain were detected in six sera (3 Karp, 1 Gilliam and 2 TC586), whereas IgM antibodies against a single OT strain (Gilliam) were noted in 3 sera (Gilliam). IgG reactive to all OT strains were present in 33 (47.1%) of the 70 sera and IgM reactive to all OT strains were present in 22 (78.6%) of the 28 sera. The fact that most sera were reactive to multiple OT strains suggests that group-specific antigens are involved in scrub typhus infections, whereas very few were due to strain-specific epitopes present on these strains. Peak IgG and IgM titers were noted more frequently against Gilliam, Karp, and TA763 strains: this suggests that these strains may be the commonest infecting strains among Malaysian patients. Two predominant OT polypeptides consistently reacted with patients' sera were the 70 kDa and 56 kDa proteins.

Antigens, Bacterial↗
PubMed2002

Virulence of Malaysian isolates of Orientia tsutsugamushi in mice.

The pathogenicity of Malaysian isolates of Orientia tsutsugamushi was investigated by a mouse virulence assay. The isolates could be differentiated as low (4 isolates), moderately (3 isolates) and highly virulent (2 isolates) based on the different responses in infected mice. No direct correlation between severity of human scrub typhus infections and virulence of the O. tsutsugamushi in mice was observed. Mice infected with virulent strains of O. tsutsugamushi showed splenomegaly, ascitis accumulation and enlargement of kidneys and livers whereas avirulent O. tsutsugamushi strains were asymptomatic and exhibited ruffled fur for a short period after infection. There was low antibody response in mice infected with isolates of low pathogenicity as compared with those of highly virulent isolates. Upon dissection of the infected mice, enlargement of mouse organs such as spleen, kidney and liver was noted. Presence of rickettsemia in mice was confirmed by the growth of O. tsutsugamushi in the L929 cells when inoculated with blood from infected mice. O. tsutsugamushi was also cultured from the peritoneal exudates of the infected mice. However, DNA of O. tsutsugamushi was only detected in the peritoneal exudates (by PCR) and blood (by cell culture) and not from other tissue samples.

Animals↗
PubMed2002

Isolation and PCR detection of rickettsiae from clinical and rodent samples in Malaysia.

Isolation of rickettsiae from patients' blood samples and organ samples of wild rodents from areas with high seroprevalence of rickettsial infections was attempted using cell culture assay and animal passages. L929 mouse fibroblast cells grown in 24 well tissue culture plate were inoculated with buffy coat of febrile patients and examined for the growth of rickettsiae by Giemsa, Gimenez staining and direct immunofluorescence assay. No rickettsiae were isolated from 48 patients' blood samples. No symptomatic infections were noted in mice or guinea pigs infected with 50 organ samples of wild rodents. There was no rickettsial DNA amplified from these samples using various PCR detection systems for Orientia tsutsugamushi, typhus and spotted fever group rickettsiae.

Adolescent↗
PubMed2001

Comparison of safety and immunogenicity of a Vi polysaccharide typhoid vaccine with a whole-cell killed vaccine in Malaysian Air Force recruits.

OBJECTIVE: To carry out a comparative study of the safety and immunogenicity of Vi polysaccharide vaccine against whole-cell killed (WCK) typhoid vaccine. METHODS: The study was carried out on young adult recruits (aged 18-25 years) of the Malaysian Air Force. A total of 125 subjects received the Vi polysaccharide vaccine and 114 received the WCK vaccine. FINDINGS: The Vi vaccine was significantly less reactogenic than the WCK vaccine with regard to systemic and local reactions. Following administration of the Vi vaccine, seroconversion rates (defined as the percentage of subjects with a 4-fold rise of baseline antibody level) of 75.5% and 67% were observed at 2 weeks and 6 weeks, respectively, after immunization, compared with 25% and 31.3% among recipients of the WCK vaccine. Of the 110 Vi vaccinees with serological data, 21 (19%) had high, seroprotective, pre-immunization levels of anti-Vi antibodies (> or = 1 microgram/ml). The majority of subjects in this group came from a region in Malaysia which is known to have high typhoid endemicity. Interestingly, these antibody levels were boosted considerably following administration of vaccine at a level that was 5-fold higher than in subjects with low pre-immunization levels. In contrast, the seroconversion rates in those receiving the Vi vaccine were higher in subjects with low pre-immunization levels of anti-Vi antibodies (76-84%), compared to those with protective levels of > or = 1 microgram/ml prior to immunization (48-57%). CONCLUSIONS: The study reaffirms the safety and efficacy of the Vi polysaccharide vaccine and identifies a hitherto unrecognized advantage in its use, i.e. it is a potent immunogen that boosted considerably the protective antibody levels among a significant number of immunologically sensitized individuals living in typhoid-endemic regions.

Adolescent↗
PubMed2001

Serological evidence of hantavirus infections in Malaysia.

Hantaviruses are primarily rodent-borne and transmission is by inhalation of virus-contaminated aerosols of rodent excreta, especially urine and saliva. The genus Hantavirus, family Bunyaviridae, comprises at least 14 serotypes and the symptoms of clinical illness range from mild fever to severe hemorrhagic manifestations with renal complications. Many countries in Southeast Asia are unaware of the importance of hantavirus infections and give them low priority. Malaysia, like other countries in the region, has conducted very few studies on the epidemiology of hantaviruses - and even these were conducted in the 1980s. Using a more extensive range of hantavirus antigens, we conducted a seroprevalence study of rodents and humans and found further evidence of hantavirus infections. Moreover, the data from the antibody profiles strongly suggest the presence of different hantaviruses at the study sites.

Animals↗
PubMed2000

Primary peritoneal pregnancy: a case report.

A 22-year-old primipara using intrauterine contraceptive device was diagnosed to be in haemorrhagic shock due to acute ruptured ectopic pregnancy. At laparotomy, both tubes and ovaries were normal and products of conception were found to be implanted on the posterior surface of uterus near the attachment of right uterosacral ligament producing a haemoperitoneum of more than 2 l. This is the fourth case report of primary abdominal pregnancy associated with intrauterine contraceptive device (IUCD).

Adult↗
PubMed2000

The increasing prevalence of Endemic Typhus in Kuala Lumpur and an evaluation of a diagnostic ELISA dot test for the detection of antibodies to Rickettsia typhi.

A seroepidemiology study was done in response to the recent increase of Endemic Typhus cases diagnosed at University Hospital. The serosurvey was based on doctors' request for the Weil Felix (WF) or the Indirect Immunoperoxidase (IIP) test in Pyrexia of Unknown Origin (PUO) patients for the years 1991 to 1997. Over the 7 years, we found that the incidence of Endemic typhus is increasing with gender (male:female = 2:1), age (20-40 years) and race distribution (Indians > Malay > Chinese) that reflects socioeconomic circumstances. A commercially available ELISA dot assay [INDX (E2R3) Dip-S-Ticks], for the detection of antibodies against R. typhi was compared with the indirect immunoperoxidase test (IIP). The ELISA assay was done against 219 IIP tested sera. The Dip-S-Ticks was found to be comparable to the IIP with a sensitivity of 91.7% and specificity of 92.8% at cut-off titres of > 1:80 IIP.

Adult↗
PubMed2000

Risk factors for Nipah virus transmission, Port Dickson, Negeri Sembilan, Malaysia: results from a hospital-based case-control study.

A hospital-based case-control study of viral encephalitis was carried out at Port Dickson Hospital, in the state of Negeri Sembilan, Malaysia. Between March and May 1999, 69 clinically diagnosed viral encephalitis cases and 31 controls were interviewed. Job histories on pig farming activities were assessed by a group of epidemiologists and veterinary surgeons. Results show that among clinical cases of viral encephalitis, 52 (75.4%) cases were diagnosed to have Nipah virus infection based on positive serology for antibodies to the cross-reacting Hendra virus antigen. The Nipah virus encephalitis was significantly associated with a history of working in pig farms (p < 0.001, OR = 196.0, 95% CI = 20.4-4741.6), history of contact with animals (p < 0.001, OR = 38.3, 95% CI = 8.2-209.0) and with history of direct contact with pigs (p = 0.002, OR = 34.4, 95% CI = 2.6-1,024.4). The Nipah virus infection was also significantly associated with history of feeding/cleaning pigs (p < 0.001, OR = 102, 95% CI = 11.9-2,271.5). These results provide evidence that involvement in pig farming activities is significantly associated with the risk of getting Nipah virus infection. They are potential risk factors for Nipah virus transmission in the major pig-producing area of Bukit Pelandok, Port Dickson Negeri Sembilan.

Adolescent↗
PubMed2000

Leptospirosis in Kuala Lumpur and the comparative evaluation of two rapid commercial diagnostic kits against the MAT test for the detection of antibodies to leptospira interrogans.

The aim of the study was to look into the epidemiology of serodiagnosed cases of leptospirosis at the University Hospital and compare two commercial ELISA Assays to the Microscopic Agglutination Test (MAT). Demographic data for all serodiagnosed cases for the years 1991-1997 were collected. From this data, 104 sera (n = 104) were selected as samples for comparative evaluation of the commercial ELISAs (INDX Dip-S-Ticks and PanBio ELISA) to the MAT test. Thirty two (n = 32) negative control sera were selected from serodiagnosed cases of other differential diagnosis of leptospira infection. The MAT test is a standard test that detects agglutination antibodies to leptospira biflexa, while the INDX Dip-S-Ticks is an ELISA dot test assaying for total anti-leptospira antibodies. The PanBio ELISA is a colorometric assay in test well strips to detect anti-leptospira IgM. The sensitivity, specificity, and efficiency of tests were calculated at a MAT cut-off value of 1:320. Demographic data showed that leptospirosis peaks during March-May and Aug-Nov coinciding with the inter-monsoon period with more men being infected than women and more adults than children. The sensitivity, specificity, and efficiency of test for the INDX Dip-S-Ticks were 83.3%, 93.8% and 87.5% while the values for the PanBio ELISA were 54.2%, 96.9% and 71.3%. The suboptimal PanBio result could be related to the blocking effect of high IgG titres or could be related to the diagnostic MAT cut-off values used in this study. The data hence reflects a pattern of transmission that is related to "wet" occupational risk factors. The commercial assays evaluated, are easier to perform but interpretation of results should be based on level of endemicity. The INDX Dip-S-Ticks allows this flexibility and is a practical alternative to the MAT test.

Adult↗
PubMed1999

Seroepidemiologic survey of Orientia tsutsugamushi, Rickettsia typhi, and TT118 spotted fever group rickettsiae in rubber estate workers in Malaysia.

The seroprevalence of Orientia tsutsugamushi, Rickettsia typhi, and TT118 spotted fever group (SFG) rickettsiae in 300 rubber estate workers in Slim River, Malaysia was determined in December 1996 and March 1997. In December, which was the wet season, 23.3%, 3.0%, and 57.3% of the population had antibodies detected against the three rickettsiae, respectively. The highest seropositive rate of 40% was detected for single infection with SFG rickettsiae, followed by a rate of 15.3% for both O. tsutsugamushi and SFG rickettsiae among the rubber estate workers. Subjects less than 21 years old had a lower seroprevalence of SFG rickettsiae compared with the other age groups. Indians had a higher seroprevalence of O. tsutsugamushi compared with other ethnic groups. Rubber tappers had a higher seroprevalence of SFG rickettsiae compared with other occupational groups. During the dry season in March 1997, there was a significant increase in the seroprevalence of R. typhi. The seroconversion rates for IgM against O. tsutsugamushi, R. typhi, and SFG rickettsiae were 5.7%, 12.3%, and 15.1%, respectively, during the four-month period. Significant variations of antibody titers towards the three rickettsiae was noted among subjects who were bled twice. This suggests a significant and continual exposure of rubber estate workers to the three rickettsiae.

Adolescent↗
PubMed1998

Cancer pain management in developing countries: a mosaic of complex issues resulting in inadequate analgesia.

Cancer pain is often undertreated even in developed countries with abundant resources and easy access to oral, parenteral, and transdermal opioids. The problems in developing nations are more complex, and as a result, these medications are not available to the vast majority of patients in Latin and South America, Eastern Europe, Asia, and Africa. Some of the reasons for this are reviewed, with India cited as a case example. In spite of serious efforts by the World Health Organization and other bodies to make oral opioids available and to educate government officials and physicians, little progress has been made in relieving pain in cancer patients in the developing world. Novel approaches that address fundamental concerns regarding opioid availability in these countries are desperately needed. One such approach, which is currently under development, is presented in this manuscript. This has the potential to make opioids available to patients in rural areas, improve compliance in the poorly educated patient, reduce the number of follow-up visits necessary for medication refills, and reduce the risk that opioids will be diverted to illicit channels. The potential for relieving cancer pain and the magnitude of this problem worldwide make it imperative that innovative approaches be tailored to the complex social issues and limited resources common to developing nations.

Developing Countries↗
PubMed1998

Immunogenic epitopes of Salmonella typhi GroEL heat shock protein reactive with both monoclonal antibody and patients sera.

A series of 122, 9-mer overlapping peptides based on the sequence of the Salmonella typhi GroEL gene was synthesized on the surfaces of polyethylene pins and screened with monoclonal antibody to GroEL and with human sera from patients with typhoid fever and normal healthy blood donors. Three immunogenic epitopes corresponding to peptides EGQDRGYSY, YSYNKETGE and GKGTEEKEK were identified upon screening with the human sera. In addition, screening of the peptides with a monoclonal antibody to GroEL detected binding to a third peptide, KGGKGTEEK, which contains a common overlapping sequence to peptide GKGTEEKEK. Identification and definition of these epitopes will be important in delineating the biological and immunological functions of this protein and in designing better diagnostic tests and vaccines.

Amino Acid Sequence↗
PubMed1997

Adequate irradiation of the internal jugular lymph node chain: technical considerations.

PURPOSE: This research aimed to study the anatomic relationship between the internal jugular vein with the surrounding internal jugular lymph node chain and the underlying bony anatomical structures which are commonly used as landmarks for radiation therapy planning. METHODS AND MATERIALS: Twelve patients with carcinoma of the head and neck region were studied prospectively. Using our three-dimensional planning system, a beam's-eye view of the internal jugular vein was projected onto a lateral and anterior simulation film. Quantitative measurements were made in every case of the anatomic relationship between the internal jugular vein and the posterior border of the cervical vertebrae and sagittal midline. RESULTS: The distance between the posterior border of the internal jugular vein and the posterior border of the cervical vertebrae ranged between 0 and 2.5 cm. The distances between the sagittal midline and the medial border of the internal jugular veins ranged between 2 and 4 cm. CONCLUSION: To ensure adequate irradiation of the internal jugular lymph nodes, the posterior border of the lateral radiation therapy upper-neck fields should be placed at least 1 cm posterior to the posterior aspect of the cervical vertebrae. The midline block used in the lower neck anterior field should not exceed 2 cm in width.

Cervical Vertebrae↗
PubMed1997

Objective evaluation of the quality of voice following radiation therapy for T1 glottic cancer.

BACKGROUND: Radiation therapy is commonly considered the treatment of choice for T1 glottic cancer. While it is generally believed that the quality of voice following irradiation is quite satisfactory, few studies have reported the results of objective assessment of voice after radiation therapy. PURPOSE: To objectively evaluate the quality of voice following radiation therapy for T1 glottic cancer. MATERIALS AND METHODS: The voices of 12 patients treated for T1 glottic cancer with radiation therapy were evaluated by acoustic analysis and speech aerodynamic studies. Eleven patients received between 6300 and 6665 cGy at a daily fraction size of 180-225 cGy. One patient received 7000 cGy at a daily fraction size of 200 cGy. Evaluation of the quality of voice was done 3 months to 7 years following completion of radiation therapy. RESULTS: The number of patients who scored abnormal values for the measurements of fundamental frequency, jitter, shimmer and harmonic to noise ratio was 2, 10, 4 and 3, respectively. The number of patients who scored abnormal values for transglottic airflow rate, subglottal pressure and glottal resistance was 12, 8 and 9, respectively. None of the studied patients scored normal values in all given tests. CONCLUSION: Although radiation therapy cures a high proportion of patients with T1 glottic cancer, the quality of voice does not return to normal following treatment.

Acoustics↗