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Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human erythroenzymopathy affecting more than 400 million people worldwide. G6PD deficiency was reported in India more than 50 years ago and the prevalence rate varies from 5.7% to 27.9% in different caste and tribal groups. Aim: To study the prevalence of, and the mutations causing, G6PD deficiency among the Siddis of Karnataka. Subjects and methods: A total of 755 individuals were screened using the DPIP dye decolorisation method and the deficiency was further confirmed by quantitative assay. Molecular characterisation was performed by PCR-RFLP method and DNA sequencing. Biochemical characterisation was performed as per WHO criteria. Results: Of the 755 individuals, 71 individuals (9.4%) were found to be G6PD deficient with an enzyme activity ranging from 0.02 to 3.83 IU/gm Hb. Mutational analysis could be performed on 49 G6PD deficient individuals and 45 (91.8%) of them showed the presence of the G6PD A- variant while the remaining 4 (8.2%) had the G6PD Kerala-Kalyan mutation. Microsatellite analysis in G6PD A- individuals showed the presence of 166/195 bp, AC/CTT alleles. Conclusions: G6PD deficiencies among the Siddis are predominantly due to G6PD A- mutation. Furthermore, biochemical parameters and the microsatellite repeat markers in the Siddi A- chromosome confirmed they are African descendants with Indian admixture. [ABSTRACT FROM AUTHOR]

Background: Scrub typhus or tsutsugamushi disease, transmitted by the bites of infected immature mites (chiggers) is a most covert re-emerging febrile infection currently. The disease is unnoticed or misdiagnosed due to low manifestation and lack of specific diagnostic tests at all levels. Failure of timely diagnosis leads to significant morbidity and mortality. Geographically this disease is widely endemic in a confined area of the Asia-Pacific region. In India, Scrub typhus infection is increasing and reported from various geographical parts during the past 10-15 yrs. Serological test is widely used for the diagnosis of the disease. Aim & Objectives: To investigate the presence of Scrub typhus infection in and around Vijayapura of North Karnataka region using serological tests and nested PCR. Materials and Method: During the period of 2015-17, a total of 209 patients presenting with acute febrile illness with rashes, body ache were examined for Scrub typhus infections by Weil Felix agglutination test and IgM ELISA. Further all the ELISA positive sampleswere tested by nested PCR using the specific primers of the gene encoding the immunodominant 56 kDa protein and PCR products were sequenced. Results: Out of 209 cases, 39 (18.5%) samples showed agglutinationin Weil Felix antigen OXK test with titre 1:160 and above. In Scrub typhus IgM ELISA 13 (6.3%) samples were positive with the OD value more than 0.5. In nested PCR, two samples were amplified a 483 base pairs diagnostic segment of the gene encoding the 56 kDa antigen of O. tsutsugamushi using specific primers. PCR product was sequenced bidirectionally, and nucleotide sequences queried against NCBI BLAST programme to identify the sequenced sample. Conclusion: Findings of our study demonstrated that, though more seropositivity of Spotted Fever Group Rickettsial infection is observed by WF test, scrub typhus infection is also circulating and causing acute febrile illness in and around Vijayapura, North Karnataka region. As the routinely used Weil felix test is less sensitive, inclusion of more specific tests like ELISA and nested PCR is very useful in proper diagnosis and patient management. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) refers to the process of post-transcriptional silencing of cellular mRNA by the application of double-stranded RNA (dsRNA). RNAi strategies have been widely employed to regulate gene expression in plants and animals including insects. With the availability of the full genome sequences of major vector mosquitoes, RNAi has been increasingly used to conduct genetic studies of human pathogens in mosquito vectors and to study the evolution of insecticide resistance in mosquitoes. This review summarizes the recent progress in our understanding of mosquito-pathogen interactions using RNAi and various methods of dsRNA delivery in mosquitoes at different stages. We also discuss potential applications of this technology to develop novel tools for vector control. [ABSTRACT FROM AUTHOR]

Introduction: Sida L. is a medicinally important genus widely used in conventional systems of medicine in India. Aim: The present study aims toward simultaneous determination of two bioactive compounds vasicine and vasicinone in root extracts of eight Sida spp. from Western Ghats, India. Materials and Methods: Determination of vasicine and vasicinone was undertaken in methanolic root extracts (10% w/v) of Sida acuta, Sida cordata, Sida cordifolia, Sida rhombifolia, Sida spinosa, Sida indica, Sida retusa and Sida mysorensis by high performance liquid chromatography (HPLC) method. The standards were prepared with the concentration of mg/mL. Data were expressed as mean values of three reading and relative standard deviations. The separation was achieved on a Waters, Nova-Pack, C18 (250 mm × 4.6 mm, 5 μ) column, with acetonitrile - 0.1 M phosphate buffer-glacial acetic acid (15: 85:1, v/v/v) as solvent system at a flow-rate of 1.0 mL/min. The effluent was monitored using ultraviolet detection at a wavelength of 300 nm. Results: Both calibration curves of standard showed good linear regression (R2 > 0.994). The limit of detection and the limit of quantification for vasicine was 0.110 and 0.333 μg/mL and for vasicinone was 0.059 and 0.179 μg/mL respectively. The vasicine content was highest in S. cordifolia (9.891 ± 0.495 μg/100 mg) and vasicinone content was rich in S. cordata (33.013 ± 1.651 μg/100 mg.) The content of vasicinone was higher than vasicine. Conclusion: HPLC method provides simple, accurate, and reproducible quantitative analysis for simultaneous determination of vasicine and vasicinone. Among the selected Sida species, S. cordifolia and S. cordata were found to be rich in the vasicine and vasicinone contents, respectively. [ABSTRACT FROM AUTHOR]

Background & objectives: Different developmental stages of Wuchereria bancrofti, the major causal organism of lymphatic filariasis (LF), are difficult to obtain. Beside this limitation, to obtain complete coding sequence (CDS) of a gene one has to isolate mRNA and perform subsequent cDNA synthesis which is laborious and not successful at times. In this study, an alternative strategy employing polymerase chain reaction (PCR) was optimized and validated, to generate CDS of Macrophage migration Inhibitory Factor-2 (wbMIF-2), a gene expressed in the transition stage between L3 to L4. Methods: The genomic DNA of W. bancrofti microfilariae was extracted and used to amplify the full length wbMIF-2 gene (4.275 kb). This amplified product was used as a template for amplifying the exons separately, using the overlapping primers, which were then assembled through another round of PCR. Results: A simple strategy was developed based on PCR, which is used routinely in molecular biology laboratories. The amplified CDS of 363 bp of wbMIF-2 generated using genomic DNA splicing technique was devoid of any intronic sequence. Interpretation & conclusions: The cDNA of wbMIF-2 gene was successfully amplified from genomic DNA of microfilarial stage of W. bancrofti thus circumventing the use of inaccessible L3-L4 transitional stage of this parasite. This strategy is useful for generating CDS of genes from parasites that have restricted availability. [ABSTRACT FROM AUTHOR]