METHODS: Adult mo squito samples were collected from January to August 2019 and were identified according to gender, species and locality. The isolation of the virus was done in C6/36 cells. Dengue NS1 antigen was carried out using direct mosquito lysate and mosquito culture supernatant. Detection and serotyping of the DENV was performed using multiplex RT-PCR and CHIKV detection using a one-step RT-PCR assay.
RESULTS: Of 91 mosquito pools, four were positive for NS1 antigen comprising two pools (2.2%) of male Ae. albopictus (Pulau Melaka and Kubang Siput) and two pools (2.2%) of Ae. aegypti (Kampung Demit Sungai). DENV 1 was detected in one pool (0.9%) of female Ae. albopictus among 114 tested Aedes pools. Two pools of 114 pools (1.7%) from both male Aedes species were positive with double serotypes, DENV 1 and DENV 2 (Pulau Melaka). However, no pool was positive for CHIKV.
INTERPRETATION CONCLUSION: The presence of DENV and the main vectors of arboviruses in Kelantan are pertinent indicators of the need to improve vector controls to reduce arbovirus infections among people in the localities.
METHOD: This study was approved by the institutional Ethics Committees. Postmortem nasal mucosa and brain tissues from patients with AD (n = 10) and normal subjects (n = 10) were collected with patient consent at the Fukushimura Brain Bank. Nasal and brain tissue homogenates were added to HEK293 cells expressing tau 3-repeat domain with the L266V and V337M mutations (3RD∗VM) or 4-repeat domain with the P301L and V337M mutations (4RD∗LM), which was fused with GFP at the C-terminus.
RESULT: GFP fluorescence was detected uniformly within the cell bodies of HEK293T cells expressing 3RD∗VM-EGFP and 4RD∗LM-EGFP. There were no changes in the fluorescence after the additions of the brain homogenates from normal subjects. In contrast, a large number of fluorescent puncta was detected both in HEK293T cells expressing 3RD∗VM-EGFP and 4RD∗LM-EGFP at 4 days after the additions of the brain homogenates from patients with AD. Furthermore, the nasal tissue homogenates from patients with AD also induce the formation of fluorescent aggregates in HEK293T cells expressing 3RD∗VM-EGFP and 4RD∗LM-EGFP. Quantitative analysis revealed that the nasal tissue homogenates from AD patients significantly induced the aggregate formation, compared with normal subjects.
CONCLUSION: These results suggest that the nasal tissues from AD patients contain tau seeds with prion activity, similar to the brain. A cellular bioassay using nasal tissues would be great potential as an AD biomarker because of the usefulness of nasal tissue biopsy, and would provide an important contribution to the development of ex vivo diagnosis method for AD using the nasal extracts.