Publications by authors named "Vanissa A Ong"

Article Synopsis
  • Koalas have recently acquired a new retrovirus called KoRV, which poses both research opportunities and conservation challenges, with two subtypes identified: KoRV-A (endogenous) and KoRV-B (exogenous).
  • A study involving 290 wild Queensland koalas over five years revealed that KoRV-A was present in 100% of the population, while only 24% were infected with KoRV-B, which was linked to severe health issues like chlamydia and cancer.
  • KoRV-B had a low transmission rate among adults (3%), but was transmitted at 100% from infected mothers to their joeys, indicating it is the more pathogenic subtype and highlighting the need for targeted conservation strategies.
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Chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection worldwide and the leading cause of preventable blindness. Reports have emerged of treatment failure, suggesting a need to develop new antibiotics to battle Chlamydia infection. One possible candidate for a new treatment is the protease inhibitor JO146, which is an effective anti-Chlamydia agent that targets the CtHtrA protein.

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The present study aimed to establish if a previously identified Chlamydia trachomatis HtrA (CtHtrA) inhibitor, JO146, is effective against currently circulating clinical isolates to validate if CtHtrA is a clinically relevant target for future therapeutic development. Inhibition of CtHtrA during the middle of the chlamydial replicative cycle until the completion of the cycle resulted in loss of infectious progeny for six unique clinical isolates representing different serovars. This supports the potential for CtHtrA to be a clinically relevant target for development of new therapeutics and suggests the importance of further investigation of JO146 as a lead compound.

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The Chlamydia trachomatis serine protease HtrA (CtHtrA) has recently been demonstrated to be essential during the replicative phase of the chlamydial developmental cycle. A chemical inhibition strategy (serine protease inhibitor JO146) was used to demonstrate this essential role and it was found that the chlamydial inclusions diminish in size and are lost from the cell after CtHtrA inhibition without formation of viable elementary bodies. The inhibitor (JO146) was used in this study to investigate the role of CtHtrA for penicillin persistence and heat stress conditions for Chlamydia trachomatis.

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The mechanistic details of the pathogenesis of Chlamydia, an obligate intracellular pathogen of global importance, have eluded scientists due to the scarcity of traditional molecular genetic tools to investigate this organism. Here we report a chemical biology strategy that has uncovered the first essential protease for this organism. Identification and application of a unique CtHtrA inhibitor (JO146) to cultures of Chlamydia resulted in a complete loss of viable elementary body formation.

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Objective: To develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Entamoeba histolytica E. histolytica, the causative agent of amebiasis.

Methods: The LAMP primer set was designed from E.

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Objective: To determine the profiles of anti-Entamoeba histolytica (E. histolytica) IgA, IgG, and IgM in sera of diarrheic and non-diarrheic individuals and partially characterize target antigens.

Methods: Serum samples from thirty diarrheic and thirty non-diarrheic individuals were subjected to IgA, IgG, and IgM profiling through enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunoblot.

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Trichomonas vaginalis is a human urogenital pathogen that causes trichomoniasis, the most common nonviral parasitic sexually transmitted infection in the world. Presently, there are no reports on comparative sequence analysis as well as on the identification of phylogenetic positions of T. vaginalis isolates from the Philippines relative to known trichomonads.

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