Porphyromonas gingivalis (W83) Infection Induces Alzheimer’s Disease-Like Pathophysiology in Obese and Diabetic Mice

Background: Periodontal disease(s) and metabolic illnesses negatively impact the quality of life and, eventually mental health. Objective: This study investigated the effect of Porphyromonas gingivalis (W83) oral infection on the development of Alzheimer’s disease (AD) pathophysiology in a wild-type obese, diabetic (db/db) mouse model. Methods: The db/db mice were either orally infected with P. gingivalis and Fusobacterium nucleatum or sham infected for 16 weeks. The presence of amyloid-β (Aβ) and neurofibrillary tangles (NFTs) were assessed using a silver impregnation technique and subsequently by immunohistochemistry for tau and neuroinflammation. The mRNA abundance of a panel of 184 genes was performed using quantitative real-time PCR, and the differentially expressed genes were analyzed by Ingenuity Pathway Analysis. Results: While no Aβ plaques and NFTs were evident by silver impregnation, immunohistochemistry (glial cell markers) of the P. gingivalis-infected mice tissue sections exhibited neuroinflammation in the form of reactive microglia and astrocytes. Anti-tau immunopositivity, in addition to cells, was prominent in thickened axons of hippocampal CA neurons. The mRNA abundance of crucial genes in the insulin signaling pathway (INSR, IGF1, IRS, IDE, PIK3R, SGK1, GYS, GSK3B, AKT1) were upregulated, potentially exacerbating insulin resistance in the brain by P. gingivalis oral infection. Increased mRNA abundance of several kinases, membrane receptors, transcription factors, and pro-inflammatory mediators indicated hyperactivation of intracellular cascades with potential for tau phosphorylation and Aβ release in the same infection group. Conclusion: P. gingivalis W83 infection of db/db mice provides a disease co-morbidity model with the potential to reproduce AD pathophysiology with induced periodontal disease.

New insights into the karyotype evolution of the genus Gampsocleis (Orthoptera, Tettigoniinae, Gampsocleidini)

Five species belonging to the genusGampsocleisFieber, 1852 were analyzed using fluorescencein situhybridization (FISH) with 18S rDNA and telomeric probes, as well as C-banding, DAPI/CMA3staining and silver impregnation. The studied species showed two distinct karyotypes, with 2n = 31 (male) and 2n = 23 (male) chromosomes. The drastic reduction in chromosome number observed in the latter case suggests multiple translocations and fusions as the main responsible that occurred during chromosome evolution. Two groups of rDNA distribution were found inGampsocleisrepresentatives analyzed. Group 1, with a single large rDNA cluster on the medium-sized autosome found in four species, carried in the haploid karyotype. Group 2, represented only byG.abbreviata, was characterized by the presence of two rDNA signals. TTAGG telomeric repeats were found at the ends of chromosome arms as expected. The rDNA clusters coincided with active NORs and GC-rich segments.

Sicuophora (Syn. Wichtermania) multigranularis from Quasipaa spinosa (Anura): morphological and molecular study, with emphasis on validity of Sicuophora (Armophorea, Clevelandellida)

Morphological studies of Sicuophora (Syn. Wichtermania) multigranularis Xiao et al., 2002, from the rectum of the frog, Quasipaa spinosa, performed using silver impregnation and scanning electron microscopy, confirmed the following newly recognized features: (1) only one apical suture on the right surface; (2) two naked regions at the posterior end of both the left and the right side of the body. Phylogenetic analysis based on the SSU-rRNA gene showed that S. multigranularis is a sister to a clade comprising all other Clevelandellida, strongly supporting the validity of the genus Sicuophora. This is also the first molecular data obtained for the genus Sicuophora. Because of the lack of molecular data, it will be necessary to obtain more genetic data from the family Sicuophoridae to discuss the question of the taxonomic status of the genus Sicuophora.

Spinal Alterations of Reil Insula in Alzheimer’s Disease

Alzheimer’s disease (AD) is a progressive neurodegenerative disease that involves numerous cellular and biochemical mechanisms resulting in synaptic alterations and extensive neuronal loss. It is primarily characterized by impairment of memory, associated frequently with mood disorders. Continuous studies have shown that insula may be an important target of AD, but neuropathological alterations have not been described extensively. In the present study, we attempted to describe the morphometric and morphological changes of the spines of Reil insula in AD in comparison with normal aging using a silver impregnation technique. We classified spines into 3 types: (1) long neck, (2) short stubby, and (3) other types; and we measured and correlated the length of them in normal controls and in individuals with AD using ImageJ application. Statistical analysis was based on the Student t test on the basis of 360 cells in SPSS v.17.0, and significance was taken as P < .05.

Granulovacuolar Degeneration in Hippocampus of Neurodegenerative Diseases: Quantitative Study

Background. Granulovacuolar degeneration (GVD) is one of the pathological features long associated with Alzheimer’s disease (AD) and normal aging. Aim. We investigate the frequency of GVDs in AD, other neurodegenerative diseases, and normal aging, with attempt to determine whether the GVD has preponderance in any particular neurodegenerative disease other than AD. Materials and Methods. A retrospective review of 111 autopsied cases with a variety of neurodegenerative diseases and 70 control cases without pathological evidence of neurodegeneration was evaluated quantitatively. The microscopic examination was applied on coronal sections of hippocampi using Hematoxylin and Eosin (H&E) and Bielschowsky silver impregnation. The mean percentage of neurons with GVDs was calculated through all sectors of Ammon’s horn for each case. Result. We found that neurons with GVD, in cases with or without neurodegenerative diseases, were found predominantly in CA1 and CA2 sectors of hippocampus. The GVD count in AD was significantly increased in CA1 and CA2 compared to other neurodegenerative cases as well as normal aging controls. In AD/LBD there was a significant increase in GVD in CA1 whereas in LBD there was no significant change in GVD. Conclusions. The frequency of GVD in AD is due to the disease process and attributes the increase for AD/LBD to the AD component.