Markers for population genetic analysis of human Plasmodia species, P. falciparum and P. vivax

Present report deals with the genetic diversity existing among the field isolates of Plasmodium falciparumand P. vivax in India. Isoenzymes and molecular markers were used to analyse field isolatesof P. falciparum and P. vivax. High level of length polymorphism was observed in repeat nucleotidesequences of MSP-1, MSP-2 and GLURP in P. falciparum isolates and CSP, GAM-1 andMSP-3α in P. vivax isolates. In study populations a high proportion of isolates (up to 60%) werecomprised of more than one genetically distinct parasite type—multiclonal. Presence of identicalallelic forms of enzyme and DNA variations in different geographical areas and in different yearssuggest that isolates belong to a single random mating population of P. vivax and P. falciparum.Observed random combination of alleles in the field isolates suggest the unlinked nature of locistudied. Study supports the feasibility of using molecular markers for the identification of recrudescencein P. falciparum from fresh infection

Ethnobotanical Studies of the Tarai Region of Kumaun, Uttarakhand, India

An ethnobotanical study was conducted during 2008–2010 in the central tarai region of Kumaun (also known as Kumaon) Himalaya in Northern India to highlight the uses of the diverse flora. The study sites included Lalkuan in Nainital district and Kichha Tehsil (covering Pantnagar) of district Udham Singh Nagar, as these occupy the major part of central tarai and have undergone massive development and settlement of people of diverse culture. The entire study area consisted of three sites and eight communities. Interviews were conducted with knowledgeable persons in the study area. A total of 206 angiosperm species recorded in this study were found to be used for medicinal, economic (aromatic, timber, spices, fuel, condiments, cosmetics, etc.), fodder, firewood, timber, food, spiritual, or some other purpose. The information was collected both from migrant and local people

Antigenic repertoire of Plasmodium vivax transmission-blocking vaccine candidates from the Indian subcontinent

<p>Abstract</p> <p>Background</p> <p>Genetic polymorphism is an inevitable component of a multistage infectious organism, such as the malaria parasite. By means of genetic polymorphism, parasite opts particular polymorph and reveals survival advantage. <it>Pvs25 </it>and <it>pvs28 </it>are sexual stage antigen genes, expressed at the ookinete stage inside the mosquito gut, and considered as potential transmission-blocking vaccine candidates. This study presents sequence variations in two important transmission blocking antigen genes <it>pvs25 and pvs28 </it>in the field isolates of <it>P. vivax </it>from the Indian subcontinent.</p> <p>Methods</p> <p>One hundred microscopically diagnosed <it>P. vivax </it>isolates were collected from five geographical regions of India. <it>Pvs25 and pvs28 </it>genes were PCR amplified and sequenced to assess sequence variation among field isolates.</p> <p>Results</p> <p>A total of 26 amino acid substitutions were observed in Pvs25 (10) and Pvs28 (16) among field isolates of <it>P. vivax</it>. Tandem repeat polymorphism observed in <it>pvs28 </it>shows 3-6 tandem repeats in the field isolates. Seven and eight novel amino acid substitutions were observed in Pvs25 and Pvs28, respectively in Indian isolates. Comparison of amino acid substitutions suggests that majority of substitutions observed in global isolates were also present in Indian subcontinent. A single haplotype was observed to be major haplotype among isolates of Delhi, Nadiad, Chennai and Panna except in isolates of Kamrup. Further, population comparison analyses suggest that <it>P. vivax </it>isolates inhabiting in north-eastern region (Kamrup) were distantly related with the isolates from remaining parts of the country. Majority of the amino acid substitutions observed in Indian isolates were more identical to the substitutions reported from isolates of Thailand and Bangladesh.</p> <p>Conclusion</p> <p>Study uncovered many new amino acid substitutions as well as a predominance of single haplotype in Indian subcontinent except in north-eastern region of the country. The amino acid substitutions data generated in this study from different geographical regions of the Indian subcontinent could be helpful in designing a more effective anti-malarial transmission-blocking vaccine.</p

Molecular epidemiology of Plasmodium vivax anti-folate resistance in India

<p>Abstract</p> <p>Background</p> <p>Sulphadoxine and pyrimethamine are anti-folate drugs that show synergistic anti-malarial effect. Point mutations in <it>dihydrofolate reductase </it>(<it>dhfr</it>) and <it>dihydropteorate synthatase </it>(<it>dhps</it>) cause anti-folate drug resistance phenotype in human malaria parasites. This study presents pattern of point mutations in <it>dhfr/dhps </it>genes among Indian sub-continent.</p> <p>Methods</p> <p>Microscopically diagnosed one hundred <it>Plasmodium vivax </it>field isolates were collected from five widely separated geographical regions of India. <it>Dhfr </it>and <it>dhps </it>genes were PCR amplified and sequenced. Previously published mutations data were collected and analyzed using Chi square test to identify geographical cluster of mutant/wild type genotypes.</p> <p>Results</p> <p>Sequence analysis revealed single (S58R), double (S58R/S117N) and quadruple (F57L/S58R/T61M/S117T/) point mutations at <it>dhfr </it>and single (A383G) to double (A383G/A553G) mutations at <it>dhps </it>in <it>P. vivax </it>field isolates. In addition, three new mutations were also observed at <it>dhfr</it>. Both, <it>dhfr </it>and <it>dhps </it>genes revealed tandem repeat variations in field isolates. <it>Dhps </it>revealed very low mutation frequency (14.0%) compared to <it>dhfr </it>(50.70%). Comparative analysis revealed a progressive increase in frequency of quadruple mutant <it>dhfr </it>genotype (p < 0.001) within five years in north-eastern state (Kamrup, Assam). Frequency of <it>dhfr </it>genotypes revealed three distinct geographical clusters of wild (northern India), double mutant (southern India), and quadruple mutant (north-eastern and island regions of India) on the Indian sub-continent.</p> <p>Conclusion</p> <p>Study suggests that SP may be susceptible to <it>P. vivax </it>in India, except Andaman and north-eastern state. The distinction of geographical regions with sensitive and resistant parasite phenotypes would be highly useful for designing and administering national anti-malarial drug policy.</p

Polymorphism and epitope sharing between the alleles of merozoite surface protein-1 of Plasmodium falciparum among Indian isolates

<p>Abstract</p> <p>Background</p> <p>The C-terminal region of merozoite surface protein-1 (MSP-1) is one of the leading candidates for vaccination against the erythrocytic stages of malaria. However, a major concern in the development of MSP-1 based malaria vaccine is the polymorphism observed in different geographical <it>Plasmodium falciparum </it>isolates. To explore whether the sequence heterogeneity of PfMSP-1 leads to variation in naturally acquired anti-MSP-1₁₉antibodies, the present study was undertaken to study PfMSP-1₁₉sequence polymorphism in malaria-endemic villages in eastern India and also carried out a competition enzyme-linked immunosorbent assay using three PfMSP-1₁₉variant forms.</p> <p>Methods</p> <p>The sequence variations in the C-terminal region of PfMSP-1₁₉were determined in a malaria endemic region. Three PfMSP-1₁₉variants were produced in <it>Escherichia coli </it>(PfMSP1₁₉QKNG-L, PfMSP1₁₉EKNG-L and PfMSP1₁₉ETSR-F) and an immunodepletion assay was carried out using the corresponding patients' sera.</p> <p>Results</p> <p>Results revealed predominance of PfMAD20 allele among Indian field isolates. Seven PfMSP-1₁₉variant forms were isolated in a singe geographical location. Three of PfMSP-1₁₉variant forms when expressed in <it>E. coli </it>showed presence of cross-reaction as well as variant specific antibodies in malaria infected patient sera.</p> <p>Conclusion</p> <p>The present study demonstrates the existence of allele specific antibodies in <it>P. falciparum</it>-infected patient sera, however their role in protection requires further investigation. These results thereby, suggest the importance of a multi-allelic PfMSP-1₁₉based vaccine for an effective malaria control.</p

Effect of myo-inositol and di-chiro inositol plus vitamin D supplementation during pregnancy on prevention of gestational diabetes: a multi-centric, prospective, randomized, double-blind clinical trial

Background: Aim of study was to evaluate the impact of myoinositol and D-chiro inositol plus vitamin D supplementation on the prevention of gestational diabetes mellitus (GDM) in pregnant women. Methods: In the multi-centric, prospective, randomised, double-blind clinical trial, either vitamin D alone (group I) or myoinositol and D-chiro inositol plus Vitamin D (group II) were administered to pregnant women from 12 weeks of gestation. The administration was continued until delivery to primigravids who were normoglycemic at 12 weeks of gestation and consented. From October 2018 to December 2019. A total of 1250 women were enrolled, and randomly allocated to either of the groups: 630 women in Group I and 620 in Group II. The allocation was blinded. The primary outcome was the rate of GDM as assessed by oral glucose tolerance test (OGTT) recommended by diabetes in pregnancy Study Group India (DIPSI), International Federation of Gynecology and Obstetrics (FIGO) and the Government of India, at first antenatal visit followed by at weeks 24 to 28 in both the groups. Results: The rate of GDM was found more in group I as compared to group II treated with myoinositol and D-chiro Inositol plus vitamin D, but the difference was not statistically significant (5.08% in group I and 3.22% in group II). Conclusions: In conclusion, an improved trend has been noticed in the reduction of the rate of GDM with myoinositol and D-chiro inositol plus vitamin D as compared to vitamin D alone. Myoinositol and D-chiro inositol plus vitamin D supplementation may be a good option for pregnant women to prevent the GDM occurrence especially in women having positive risk factors for GDM.

Allelic dimorphism of Plasmodium vivax gam-1 in the Indian subcontinent

BACKGROUND: Genetic polymorphism is an inevitable component of a complex organism especially in multistage infectious organisms such as malaria parasites. Understanding the population genetic structure of the parasites would provide valuable information for effective malaria control strategies. Recently, the development of molecular tools like PCR has made analysis of field samples possible and easier and research on Plasmodium vivax has also been strengthened. Not many reports are available on the genetic polymorphism of P. vivax from the Indian sub-continent. This study evaluates the extent of diversity in field isolates of India with respect to Pvgam-1. METHODS: A study was designed to assess the diversity of Pvgam-1 among field isolates from India, using a nested PCR assay. Field isolates were collected from different regions of the country and the observed variability was confirmed by sequencing data. RESULTS: Both Belem and Chesson type alleles were present either exclusively or in mixed form among isolates of all 10 study sites. The Belem type allele was predominant, occurring in 67% of isolates. The proportion of isolates showing the mixed form (both Belem and Chesson type alleles occurring together in the same isolate) was about 13 overall (up to 38.5% in some isolates). Sequencing of the PCR-amplified Belem and Chesson type alleles confirmed the PCR results. Among the 10 study sequences, 11 polymorphic sites and four singleton variations were observed. All the nucleotide substitutions were non-synonymous. CONCLUSION: Study shows limited diversity of Pvgam-1 marker in Indian isolates with well representation of both Belem and Chesson type alleles