Effect of gamma radiation on life history traits of Aedes aegypti (L.)

AbstractAedes aegypti is an important vector for Dengue and Dengue hemorrhagic fever. Considering its medical importance and its relevance as a model system, this study was undertaken to evaluate the impact of different doses of gamma radiation for three generations of A. aegypti. Two to three days old virgin males of A. aegypti were irradiated with 15 doses of gamma radiation, ranging from 1 to 50Gy and were immediately mass mated with the same aged virgin females. Observations were made for changes on their life history traits, particularly fecundity, hatchability, adult emergence, sex ratio and longevity, for three generations. Adult males exposed 30, 35, 40, 45 and 50Gy doses showed a significant decrease in fecundity in F0 generations. While hatchability was observed to have decreased with increasing radiation doses from 3Gy onwards in the F1 generation, samples irradiated with 30, 35, 40, 45 and 50Gy maintained significant decline in hatchability in their succeeding generations, F2 and F3 also. Similarly, a decline was observed in adult emergence from 3Gy onwards in all three generations. A male favoring sex ratio distortion was observed at the doses of 35, 40, 45 and 50Gy in all three generations. Following exposure to 4Gy, parental males and the resultant progeny showed increased longevity by 10.56 and 8.66days respectively. Similarly, the F1 generations of samples irradiated with 30, 35 and 40Gy exhibited an increase in longevity by 7.16, 7.44 and 6.64days respectively. Dose response curve for fertility among the three generations was drawn and presented. The effect of radiological exposure on the life history traits of A. aegypti varies with dose for the three generations studied. These results have potential implications in mutational studies and risk assessment and also contribute to a better understanding towards employment of the sterile insect technique in A. aegypti, plausibly paving the way to an effective mosquito genetic control program

A Cytogenetic Photomap from Ovarian Nurse Cell Polytene Chromosome of Anopheles Stephensi (Diptera: Culicidae) : A Comparative Study

Polytene chromosome banding patterns have long been used to infer the degree of relatedness among taxa and as a standard reference for locating genes, pufs, and inversion breakpoints of unique gene arrangements. Chromosome comparisons between the species over the time have shown organizational changes in patterns which have resulted in adaptive advantages. An attempt has been made to prepare chromosome map from the ovarian nurse cell of Anopheles (Cellia) stephensi Liston, and to re-evaluate the physical map of this species. The photomaps prepared, were compared with other available maps of the past for the same species. The images of the polytene chromosomes have been straightened and divided by numbered divisions and lettered subdivisions. Tentative inversion breakpoints occurring naturally and that recorded from diferent insecticide resistant strains of An. stephensi is described in the present map. Some of the re-arrangements acquired have been highlighted in the paper in view to provide an overview of the importance of cytogenetic maps to Anopheles biology and the concept of chromosome evolution

Inheritance Pattern of Temephos Resistance, an Organophosphate Insecticide, in Aedes aegypti (L.)

The present paper reports the mode of inheritance of resistance in laboratory induced temephos resistant and susceptible strains of Ae. aegypti. Homozygous resistant and susceptible strains of Ae. aegypti were generated by selective inbreeding at a diagnostic dose of 0.02 mg/L of temephos. Genetic crosses were carried out between these strains to determine the inheritance pattern of temephos resistance. The log-dosage probit mortality relationships and degree of dominance (D) were calculated. The dosage-mortality (d-m) line of the F1 generation was nearer to the resistant parent than the susceptible one. The “D” value was calculated as 0.15 indicating that the temephos resistant gene is incompletely dominant. The d-m lines of the F2 generation and progeny from the backcross exhibited clear plateaus of mortality across a range of doses indicating that temephos resistance is controlled by a single gene. Comparison of the mortality data with the theoretical expectations using the χ2 test revealed no significant difference, confirming a monogenic pattern of inheritance. In conclusion, the study provides evidence that the temephos resistance in Ae. aegypti follows an incompletely dominant and monogenic mode of inheritance

Effects of circadian clock disruption on gene expression and biological processes in Aedes aegypti

Abstract Background This study explores the impact of disrupting the circadian clock through a Cycle gene knockout (KO) on the transcriptome of Aedes aegypti mosquitoes. The investigation aims to uncover the resulting alterations in gene expression patterns and physiological processes. Results Transcriptome analysis was conducted on Cyc knockout (AeCyc -/-) and wild-type mosquitoes at four time points in a light-dark cycle. The study identified system-driven genes that exhibit rhythmic expression independently of the core clock machinery. Cyc disruption led to altered expression of essential clock genes, affecting metabolic processes, signaling pathways, stimulus responses and immune responses. Notably, gene ontology enrichment of odorant binding proteins, indicating the clock's role in sensory perception. The absence of Cyc also impacted various regulation of metabolic and cell cycle processes was observed in all time points. Conclusions The intricate circadian regulation in Ae. aegypti encompasses both core clock-driven and system-driven genes. The KO of Cyc gene instigated extensive gene expression changes, impacting various processes, thereby potentially affecting cellular and metabolic functions, immune responses, and sensory perception. The circadian clock's multifaceted involvement in diverse biological processes, along with its role in the mosquito's daily rhythms, forms a nexus that influences the vector's capacity to transmit diseases. These insights shed light on the circadian clock's role in shaping mosquito biology and behavior, opening new avenues for innovative disease control strategies

Additional file 1 of Effects of circadian clock disruption on gene expression and biological processes in Aedes aegypti

Additional file 1: Table S1. Summary statistics of sequencing data for AeCyc-/-and WT transcriptome analysis including mapping totals, Q20 and GC percentage. Table S2. Differentially expressed up and down regulated genesshowing from volcano plot at four different time points in a LD cycle. Table S3. Differentially expressed genes in a heatmap (>5-fold change) at four different time points in a LD cycle. Table S4. Differentially expressed genes GO enriched at four different time points in a LD cycle, specifically for GO:BP, Sensory perception (GO:0007600), Nervous System Process (GO:0050877), G protein-coupled receptor signaling pathway (GO:0007186), Odorant binding (GO:0005549), Immune response (GO:0006955), etc. Figure S1. Gene ontology (GO) enrichment analysis for rhythmically differentially expressed genes in Cyc KO-specific and WT-specific groups. (A) Enriched GO term biological processes for Cyc KO-specific genes. (B) Enriched KEGG pathways for Cyc KO-specific genes. (C) Enriched GO term biological processes for WT specific genes. (D) Enriched KEGG pathways for WT specific genes. Only the top 20 were shown. The x-axis represents the proportion of genes that belong to a given functional category to the total number of differentially expressed genes. p-values were corrected using the Benjamini–Hochberg method

Corrosion inhibition of 2024-T3 aluminum alloy in 3.5% NaCl by thiosemicarbazone derivatives

Three thiosemicarzone derivatives, namely (E)-2-(2-hydroxybenzylidene) hydrazinecarbothioamide(MHC), (E)-2-(2,4-dihydroxybenzylidene)hydrazinecarbothioamide (DHC) and (E)-2-(2,3,4-trihydroxybenzylidene)hydrazinecarbothioamide (THC) were synthesized and their corrosion inhibition action on 2024-T3 aluminum alloy was studied in 3.5% NaCl solution. The surface morphology and surface composition of the corroded alloy were examined using FESEM, 3D profilometry, EDX spectroscopy and X-ray photoelectron spectroscopy. The synthesized inhibitors were found to provide corrosion protection on AA2024-T3 by forming an adsorbed layer of the complex on the alloy surface. They exhibited inhibition efficiency in the order, MHC < DHC < THC. Quantum chemical calculations corroborated the experimental results

Evaluation of the Indian TrueNAT micro RT-PCR device with GeneXpert for case detection of pulmonary tuberculosis

To evaluate the performance of TrueNAT (RT Micro PCR device) assay in comparison with GeneXpert on sputum samples from pulmonary cases of tuberculosis. 274 samples were processed to detect MTB by ZN smear examination, MGIT culture and molecular methods that included RT-PCR (ABI 7500 & TrueNAT) and GeneXpert for case detection of TB. The overall performance of the test with MGIT(Mycobacterium Growth Indicator Tube) culture as gold standard, sensitivity of smear, RT PCR/TrueNAT and Genexpert was 61.5% (CI:53.3–69.3%), 94.7% (CI:89.8–97.6%) & 96.0% (CI: 91.5–98.5%), respectively. Amongst the S+ (108) samples, RT-PCR/TrueNAT and GeneXpert showed a sensitivity of 99% (CI:94.9%–99.8%) and 100% (98.6%–100.0%), respectively. High concordance was observed between GeneXpert and TrueNAT for case detection of TB. The GeneXpert MTB/RIF test was independent on the user's skills. It has a short turn-around time and simultaneously detects RIF resistance with M. tuberculosis in less than 3 h. The TrueNAT MTB has good sensitivity and specificity in case detection with hands on time of less than 3 h as well as fits the requirements in resourcelimited health care settings. Larger, multi-site studies are required to obtain better estimates of the performance of TrueNAT MTB

Cu(II) immobilized on guanidine functionalized Fe3O4 magnetic substrate as a heterogeneous catalyst for selective reduction of nitroarenes

In the present work, copper (II) immobilized on guanidine functionalized Fe3O4 nanoparticles (Fe3O4@Guanidine-Cu-II) are developed as a heterogeneous catalyst. Fe3O4@Guanidine-Cu-II is well-characterized by adopting FT-IR, XRD, SEM, TEM, EDX, SEM-elemental mapping, TG-DTA, XPS, ICP-OES, and VSM analysis. Fe3O4@Guanidine-Cu-II is employed for the selective reduction of nitro group on electronically diversified nitroarenes involving NaBH4 to serve as a hydrogen source in ethanol medium. Anilines resulted from the reduction of nitroarenes are of excellent yields with high TON and TOF numbers, indicating the efficiency of the prepared catalyst. Also, the catalyst has been recovered with effective yield over the time of the reaction, and the recovered catalyst was used up to eight cycles for the reaction without any significant change in the catalytic activity. This notable feature of the prepared catalytic system makes it highly promising, not only for an industrial but also from an environmental point of view