Basic Science and Pathogenesis.

Background: The common APOE2/E3/E4 polymorphism, the strongest risk factor for Alzheimer's disease (AD), is determined by two-site haplotypes at codons 112 (Cys>Arg) and 158 (Arg>Cys), resulting into six genotypes. Due to strong linkage disequilibrium between the two sites, 3 of the 4 expected haplotypes (E2, E3, E4) have been observed and extensively studied in relation to AD risk. Compared to the most common haplotype of E3 (Cys112 - Arg158), E4 (Arg112 - Arg 158) and E2 (Cys112 - Cys158) haplotypes are determined by a single-point mutation at codons 112 and 158, respectively.

Basic Science and Pathogenesis.

Background: Many complex traits and diseases show sex-specific biases in clinical presentation and prevalence. For instance, two-thirds of AD cases are female. Studies suggest that women might have higher cognitive reserve but steeper cognitive decline in older age.

Anti-infective Efficacy of Mechanical Debridement with Adjunctive Modalities on Clinical and Cytokine Parameters in Treatment of Chronic Periodontitis: Randomized Controlled Clinical Trial.

Objectives:  Periodontal debridement involves conventional scaling and root planing (SRP) along with variant forms of adjunctive therapies. In the present clinical trial, we investigated if the adjunctive use of HybenX gel or diode laser along with SRP could provide a favorable outcome for the treatment of chronic periodontitis.

Materials And Methods:  The present study involved 60 subjects diagnosed with chronic periodontitis who were randomly assigned as test groups (laser or HybenX) or control group (SRP alone).

Meta-analysis of age-related cognitive decline reveals a novel locus for the attention domain and implicates a COVID-19-related gene for global cognitive function.

Introduction: Cognitive abilities have substantial heritability throughout life, as shown by twin- and population-based studies. However, there is limited understanding of the genetic factors related to cognitive decline in aging across neurocognitive domains.

Methods: We conducted a meta-analysis on 3045 individuals aged ≥65, derived from three population-based cohorts, to identify genetic variants associated with the decline of five neurocognitive domains (attention, memory, executive function, language, visuospatial function) and global cognitive decline.

Investigation of the independent role of a rare APOE variant (L28P; APOE*4Pittsburgh) in late-onset Alzheimer disease.

A rare missense APOE variant (L28P; APOE*4Pittsburgh), which is present only in populations with European ancestry, has been reported to be a risk factor for late-onset Alzheimer's disease (LOAD). However, due to the complete linkage disequilibrium of L28P with APOE*4 (C112R), its independent genetic association is uncertain. The original association study implicating L28P with LOAD risk was carried out in a relatively small sample size.