Evaluation of Diagnostic Potential of Recombinant Outer Membrane Protein (rOmp28) of Brucella Melitensis for Serodiagnosis of Ovine and Caprine Brucellosis

Brucella melitensis is the main causative agent of brucellosis in small ruminants. The diagnosis of brucellosis is mostly done by isolation of bacteria from aborted material, udder secretions or from tissues of infected animals. The presumptive diagnosis of Brucellosis is attempted by elucidating the serological responses to Brucella antigens. The present study was designed to evaluate the diagnostic potential of rOmp28 antigen of Brucella melitensis for ovine and caprine brucellosis. A total of 163 clinical samples (n=79 samples of ovine and n=84 samples of caprine) were tested in an indirect plate-ELISA format using rOmp28 antigen. Results of rOmp28 antigen based indirect ELISA were also compared with the native antigens [cell envelope antigen (CE) and whole cell sonicated antigen (SA)] based ELISA and with conventional Standard Tube Agglutination Test (STAT). Recombinant Omp28 antigen showed high sensitivity and specificity i.e., 71.4%, 97.7% for ovine samples and 74%, 87.8% for caprine samples as compared with CE antigen (40%, 75%) and (44%, 67.6%) and SA antigen (37.1%, 84%) and (42%, 70.5%) for ovine and caprine samples respectively. This study demonstrated that rOmp28 can be a good candidate antigen in the serodiagnosis of ovine and caprine brucellosis in India and also further in the development of rapid field-adaptable diagnostic assay for screening of ovine and caprine brucellosis

Identification of New PCR Targets and its Validation for Development of Nucleic Acid-based Detection Assay for Melioidosis

Burkholderia pseudomallei the gram negative, soil saprophyte is the causative agent of melioidosis in human and animals. Development of rapid, sensitive, species specific and cost effective molecular assays are needed for detection of B. pseudomallei from clinical and environmental samples and to differentiate it from other closely related bacterial species. In this study, insilico approach was used to identify new species specific gene targets for molecular diagnosis of B. pseudomallei. The identified targets were then analyzed by SYBR Green real time PCR assay for their specificity, sensitivity and presence across different Indian clinical and soil isolates of B. pseudomallei. Out of the three targets studied SYBR Green real time PCR assay targeting bpss0091 gene of B. pseudomallei was found 100% specific, having detection limit of 12.3fg/µl DNA. The bpss0091 gene target was present in all clinical and soil isolates of B. pseudomallei tested thus suggesting bpss0091 gene based SYBR Green real time PCR assay will be useful for detection of B. pseudomallei in different geographical regions

Resistance Status of the Malaria Vector Mosquitoes, Anopheles stephensi and Anopheles subpictus Towards Adulticides and Larvicides in Arid and Semi-Arid Areas of India

Susceptibility studies of malaria vectors Anopheles stephensi Liston (Diptera: Culicidae) and An. subpictus Grassi collected during 2004–2007 from various locations of Arid and Semi-Arid Zone of India were conducted by adulticide bioassay of DDT, malathion, deltamethrin and larvicide bioassay of fenthion, temephos, chlorpyriphos and malathion using diagnostic doses. Both species from all locations exhibited variable resistance to DDT and malathion from majority of location. Adults of both the species were susceptible to Deltamethrin. Larvae of both the Anopheline species showed some evidence of resistance to chlorpyriphos followed by fenthion whereas susceptible to temephos and malathion

Biological warfare agents

The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies

Evaluation of recombinant porin (rOmp2a) protein as a potential antigen candidate for serodiagnosis of Human Brucellosis

Abstract Background Brucellosis is an important zoonotic disease caused by different Brucella species and human brucellosis is commonly prevalent in different states of India. Among various Brucella species, B. melitensis is most pathogenic to human and included as category B biothreat which can cause infection through aerosol, cut, wounds in skin and contact with infected animals. The diagnosis of human brucellosis is very important for proper treatment and management of disease as there is no vaccine available for human use. The present study was designed to clone, express and purify immunodominant recombinant omp2a (rOmp2a) porin protein of B. melitensis and to evaluate this new antigen candidate for specific serodiagnosis of human brucellosis by highly sensitive iELISA (indirect enzyme linked immunosorbent assay). Method Omp2a gene of B. melitensis 16 M strain was cloned and expressed in pET-SUMO expression system. The recombinant protein was purified under denaturing conditions using 8 M urea. The purified recombinant protein was confirmed by western blotting by reacting with anti-HIS antibody. The sero-reactivity of the recombinant protein was also checked by reacting with antisera of experimentally infected mice with B. melitensis 16 M at different time points. Serodiagnostic potential of recombinant porin antigen was tested against 185 clinical serum samples collected from regions endemic to brucellosis in southern part of India by iELISA. The samples were grouped into five groups. Group 1 contained cultured confirmed positive serum samples of brucellosis (n = 15), group 2 contained sera samples from positive cases of brucellosis previously tested by conventional methods of RBPT (n = 28) and STAT (n = 26), group 3 contained sera samples negative by RBPT(n = 36) and STAT (n = 32), group 4 contained sera samples of other febrile illness and PUO case (n = 35) and group 5 contained confirmed negative sera samples from healthy donors (n = 23). Result The rOmp2a was found to be immunoreactive by iELISA and western blotting. The test showed a sensitivity of 93.75% and specificity of 95.83% when tested against 185 serum samples. For determination of statistical significance between experimental groups and control groups, Student’s t test was performed on the data. Conclusion Omp2a emerges as a potential antigen candidate for serodiagnosis of human brucellosis

Synthesis and Antimalarial Evaluation of Cyclic β-Amino Acid-Containing Dipeptides

This paper describes an efficient synthesis and the antiparasitic evaluation ofcyclic β-amino acid-containing dipeptides 3.1-3.6 and 4.1-4.5. The antimalarial propertiesof all these dipeptides have been evaluated in vitro against Plasmodium falciparum and invivo against Plasmodium berghai. Compounds 4.4 and 4.5 have been found to be veryeffective in this respect, with IC50 values of 3.87 and 3.64 μg/mL in the in vitro test, while4.5 has also been found to be active in the in vivo evaluation