Validity Assessment of an Automated Brain Morphometry Tool for Patients with De Novo Memory Symptoms.

BACKGROUND AND PURPOSE: Automated volumetric analysis of structural MR imaging allows quantitative assessment of brain atrophy in neurodegenerative disorders. We compared the brain segmentation performance of the AI-Rad Companion brain MR imaging software against an in-house FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline. MATERIALS AND METHODS: T1-weighted images of 45 participants with de novo memory symptoms were selected from the OASIS-4 database and analyzed through the AI-Rad Companion brain MR imaging tool and the FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline. Correlation, agreement, and consistency between the 2 tools were compared among the absolute, normalized, and standardized volumes. Final reports generated by each tool were used to compare the rates of detection of abnormality and the compatibility of radiologic impressions made using each tool, compared with the clinical diagnoses. RESULTS: We observed strong correlation, moderate consistency, and poor agreement between absolute volumes of the main cortical lobes and subcortical structures measured by the AI-Rad Companion brain MR imaging tool compared with FreeSurfer. The strength of the correlations increased after normalizing the measurements to the total intracranial volume. Standardized measurements differed significantly between the 2 tools, likely owing to differences in the normative data sets used to calibrate each tool. When considering the FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline as a reference standard, the AI-Rad Companion brain MR imaging tool had a specificity of 90.6%-100% and a sensitivity of 64.3%-100% in detecting volumetric abnormalities. There was no difference between the rate of compatibility of radiologic and clinical impressions when using the 2 tools. CONCLUSIONS: The AI-Rad Companion brain MR imaging tool reliably detects atrophy in cortical and subcortical regions implicated in the differential diagnosis of dementia.

Statewide Efficacy Assessment of Insect Growth Regulators Against Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia: An Alternative Control Strategy?

The efficacy of three groups of insect growth regulators, namely juvenile hormone mimics (methoprene and pyriproxyfen), chitin synthesis inhibitors (diflubenzuron and novaluron), and molting disruptor (cyromazine) was evaluated for the first time, against Aedes albopictus Skuse (Diptera: Culicidae) larvae from 14 districts in Sabah, Malaysia. The results showed that all field populations of Ae. albopictus were susceptible towards methoprene, pyriproxyfen, diflubenzuron, novaluron, and cyromazine, with resistance ratio values ranging from 0.50-0.90, 0.60-1.00, 0.67-1.17, 0.71-1.29, and 0.74-1.07, respectively. Overall, the efficacy assessment of insect growth regulators in this study showed promising outcomes and they could be further explored as an alternative to conventional insecticides.

Bioefficacy of mosquito mat vaporizers and associated metabolic detoxication mechanisms in Aedes aegypti (Linnaeus) in Selangor, Malaysia: A statewide assessment.

This study aims to examine the efficacy of mosquito mat vaporizers on Aedes aegypti and their associated metabolic detoxication mechanisms. For this purpose, Aedes aegypti (Linnaeus) was collected from nine districts in Selangor, Malaysia and tested with mosquito vaporizing mat bioassays. The same populations were also subjected to biochemical assays to investigate activities of detoxifying enzymes, namely non-specific esterase (EST), glutathione-S-transferase (GST) and mixed function oxidase (MFO). The efficacy of Ae. aegypti on the active ingredients tested in decreasing order were d- allethrin > dimefluthrin > prallethrin with PBO > prallethrin. The results further indicated significant enhancement mean levels of EST, GST and MFO in pyrethroid-resistant populations. The mortality rate of Ae. aegypti in response to pyrethroid active ingredients was associated with MFO activity, suggesting it is an important detoxification enzyme for the populations tested. In view of the presence of resistance against household insecticide products, pyrethroid efficacy on Ae. aegypti populations needs to be monitored closely to ensure the implementation of an effective vector control program in Malaysia.

Assessment of the susceptibility status of Aedes albopictus (Diptera: Culicidae) from Interior, Sandakan and Tawau divisions of Sabah, Malaysia based on WHO diagnostic doses of larvicides.

Susceptibility status of Aedes albopictus (Skuse) sampled from residential areas in Interior, Sandakan and Tawau divisions of Sabah, Malaysia, was evaluated based on the WHOrecommended doses of organochlorine and organophosphate larvicides. To determine susceptibility status, larval bioassays were carried out and post 24-hour mortalities based on WHO resistance classifications were adopted. The results demonstrated that Ae. albopictus larvae were resistant toward 5 out of the 8 larvicides tested. Larvae from all populations were resistant against bromophos, fenitrothion, malathion, temephos and dichlorodiphenyltrichloroethane (DDT), with mortalities ranging from 0.00 to 89.33%. Dieldrin, on the other hand, could induce 100.00% mortalities in all populations, followed by fenthion and chlorpyrifos, with mortalities ranging from 97.33 to 100.00% and 81.33 to 100.00% respectively. Despite most populations exhibiting similitude in their resistance status, larvae from Sandakan exhibited the highest resistance level whereas the lowest level was observed in Keningau. In view of the inadequacy of some larvicides in controlling Ae. albopictus in this study, integrated management such as insecticide rotation or combination of interventions is warranted.

Adulticide Resistance Status of Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia: A Statewide Assessment.

Resistance status of Aedes albopictus (Diptera: Culicidae) collected from Sabah, East Malaysia, was evaluated against four major classes of adulticides, namely pyrethroid, carbamate, organochlorine, and organophosphate. Adult bioassays conforming to WHO standard protocols were conducted to assess knockdown and mortality rates of Ae. albopictus. Among tested pyrethroid adulticides, only cyfluthrin, lambda-cyaholthrin, and deltamethrin were able to inflict total knockdown. The other adulticide classes mostly failed to cause any knockdown; the highest knockdown rate was only 18.33% for propoxur. With regards to mortality rate, Ae. albopictus was unanimously susceptible toward all pyrethroids, dieldrin, and malathion, but exhibited resistance toward bendiocarb, propoxur, dichlorodiphenyltrichloroethane, and fenitrothion. Additionally, correlation analysis demonstrated cross-resistance between bendiocarb and propoxur, and malathion and propoxur. In conclusion, this study has disclosed that pyrethroids are still generally effective for Aedes control in Sabah, Malaysia. The susceptibility status of Ae. albopictus against pyrethroids in descending order was cyfluthrin > lambda-cyhalothrin > deltamethrin > etofenprox > permethrin.