Myitkyina University

The distribution of Culex quinquefasciatus as a vector for several tropical diseases in Indonesia could affect the transmission of various pathogens, including filariasis, West Nile, encephalitis, and Rift Valley fever. The use of insecticides to control mosquito populations is carried out massively. However, this effort is threatened by an increase in mosquito resistance to insecticides, in this case, pyrethroids that target Voltage-gated sodium channel (VGSC) as a complex protein in mosquito nerve cells that plays a role in the movement of sodium ions, where these compounds can have a knockdown effect and lead to death. The existence of a single nucleotide mutation in this specific codon results in knockdown resistance (kdr) in mosquitoes. This study aims to determine whether there is a kdr mutation in the Vgsc-L1014F target using the latest molecular method ETAS-PCR to type tri-allelic variation at Vgsc-1014 in Cx. quinquefasciatus samples collected in three areas in the cities of Surabaya and Sidoarjo, namely Wonocolo, Sukodono, and Wonoayu. The result showed ten male pool samples (C1-C10) of Cx. quinquefasciatus did not carry mutations or present as homozygous wild type (TTT/TTT), with a DNA band size of 181 bp. Hence, this preliminary study could be extended for further research to build vector control monitoring programs.

Highlights: This research analyzed a previously understudied subject in Surabaya, Indonesia, and discovered knockdown resistance (kdr) mutations in Aedes albopictus. The findings of this study can prompt further research, including bioassay testing and the development of more potent insecticides. Abstarct : Dengue hemorrhagic fever (DHF) has been endemic in Indonesia for decades. Insecticides are necessary to manage the transmission of the dengue virus. However, prolonged use of insecticides can lead to insecticide resistance. This study aimed to examine the genotype of mosquitoes using the allele-specific polymerase chain reaction (ASPCR) method. The ASPCR method was chosen for genotype detection due to its high sensitivity, affordability, and ease of design. Five mosquitoes were collected from human habitation in four different areas of Surabaya, Indonesia, namely Kranggan, Ulul Azmi Mosque, Ploso, and Kalijudan. Among them, three samples were identified as Aedes albopictus (A1, A2, and A5) and two samples were identified as Aedes aegypti (A3 and A4). The frequency of resistant alleles was analyzed using the Hardy-Weinberg package in RStudio version 2023.03.1. This study revealed that two mosquitoes carried homozygous mutant alleles with a band of 113 bp and three mosquitoes carried homozygous wild-type alleles with a band of 93 bp. Cysteine-to-cysteine (C/C) mutations and phenylalanine-to-phenylalanine (F/F) mutations at codon 1534 were observed in Aedes aegypti and Aedes albopictus mosquitoes. The homozygous mutant alleles were found in Kranggan, Surabaya, Indonesia. Further research is required to assess insecticide resistance and knockdown resistance (kdr)-like mutation by collecting more representative samples from larger areas within the region of Surabaya. Nevertheless, this study can be used as a reference for vector control and early prevention of dengue fever.

Context: Human immunodeficiency virus (HIV) antiretrovirals that target the binding of viral enzyme are chosen as the lead solution in the treatment of HIV-1 infection, such as non-catalytic site integrase inhibitor (NCINI), nevirapine, and darunavir. There are natural compounds from specific plants that can be effective in treating HIV-1 infection such as tea catechin. Tea catechin administration causes a decrease in viral load and inhibition of entry mechanisms and an increased effect of apoptosis in infected cells. Aims: To identify the triple inhibitor mechanism in tea catechins against the three HIV-1 enzymes and apoptosis agonists through in silico approach as an innovation in handling HIV-1 infection. Methods: The 3D structure of tea catechin compounds from the database was examined, and then all target compounds were analyzed for drug-likeness, molecular docking, pathway prediction, and molecular interactions to determine the potential of tea catechin compounds as antiviral HIV-1 in silico. Results: Tea catechin compounds have the potential to serve as antiviral against HIV-1 through apoptosis agonist and triple inhibitor mechanisms. Apoptosis occurs due to the interaction of tea catechins with pro-apoptotic proteins in cells, and the epigallocatechin gallate (EGCG) compound is a class of tea catechins with the same binding position as control. Conclusions: The binding of the EGCG molecule complex results in low binding energy. Therefore, it allows EGCG acts as a triple inhibitor in HIV-1 infection.