Basic Science and Pathogenesis.

Background: Down syndrome (DS) is characterized by the overexpression of the amyloid precursor protein gene (APP) and pro-inflammatory genes, leading to progressive beta-amyloid (Aβ) accumulation. This accumulation in DS may exacerbate neuroinflammation, contributing to the pathogenesis of Alzheimer's Disease (AD). Experimental models suggest that aquaporin 4 (AQP4), an astrocytic water channel implicated in Aβ clearance, is mislocalized with increased Aβ burden.

Basic Science and Pathogenesis.

Background: The prevalence of Alzheimer's disease (AD) pathologies in people with Down syndrome (DS) is nearly 100%. In DS, overexpression of APP (on chr21) is associated with increased production of amyloid beta (Aβ) and the formation of phosphorylated tau (ptau) tangles. In the general population, women exhibit higher burdens of ptau compared to age-matched men with AD.

Basic Science and Pathogenesis.

Background: Brain deposits of amyloid-β (Aβ), one of the hallmark pathologies of Alzheimer disease (AD), are consistently present in people with Down syndrome (DS) after the age of 30 years. Positron emission tomography (PET) radioligands like [3H]Pittsburgh Compound-B (PiB) allow for visualizing Aβ accumulation in living people. In DS, the earliest and strongest PiB-PET retention is in the striatum, differing from late-onset AD.

Neuropathology of trisomy 21 mosaicism in a case with early-onset dementia.

Introduction: This study investigated the impact of trisomy 21 mosaicism (mT21) on Alzheimer's disease (AD) neuropathology in a well-characterized clinical case described by Ringman et al.

Methods: We describe AD neuropathology in mT21 including amyloid beta, phosphorylated tau, astrogliosis, microgliosis, α-synuclein, and TAR DNA-binding protein 43 (TDP-43) in cerebral cortex, hippocampal subregions, and amygdala using immunohistochemistry.

Results: We observed high AD neuropathologic change with a score of A3B3C3.

The potency of a liquid biofertilizer containing bacterial strains of spp. on recovery of soil properties damaged by Al and Fe toxins and enhancement of rice yield in acid sulfate soil.

In the Mekong Delta Vietnam, rice is heavily affected by Al and Fe ions appearing in local acid sulfate soils (AAS). Therefore, the current study was carried out to assess the efficacy of a liquid biofertilizer (LB) containing nitrogen-fixing and phosphorus-solubilizing bacterial strains of spp. on remediation of soil characteristics and improvements of rice uptakes, growth, and yield.

Untargeted Phylogenetic Group III of Multi-drug-Resistant Bacillus cereus Isolated Using Fraser Medium from Retail Chickens in Ho Chi Minh City.

The prevalence of food-borne bacteria in developing countries is less well understood than in developed countries. The ISO11290-1 isolation method is commonly used to study Listeria contamination in chicken; however, all isolates are identified as untargeted Bacillus cereus. This study aimed to determine the classification, antibiotic susceptibility, and virulence genes of B.

Constant pH Accelerated Molecular Dynamics Investigation of the pH Regulation Mechanism of Dinoflagellate Luciferase.

The bioluminescence reaction in dinoflagellates involves the oxidation of an open-chain tetrapyrrole by the enzyme dinoflagellate luciferase (LCF). The activity of LCF is tightly regulated by pH, where the enzyme is essentially inactive at pH ∼8 and optimally active at pH ∼6. Little is known about the mechanism of LCF or the structure of the active form of the enzyme, although it has been proposed that several intramolecularly conserved histidine residues in the N-terminal region are important for the pH regulation mechanism.

The biosynthetic pathway of coenzyme F430 in methanogenic and methanotrophic archaea.

Methyl-coenzyme M reductase (MCR) is the key enzyme of methanogenesis and anaerobic methane oxidation. The activity of MCR is dependent on the unique nickel-containing tetrapyrrole known as coenzyme F430. We used comparative genomics to identify the coenzyme F430 biosynthesis (cfb) genes and characterized the encoded enzymes from Methanosarcina acetivorans C2A.

Prevalence, antibiotic resistance, and extended-spectrum and AmpC β-lactamase productivity of Salmonella isolates from raw meat and seafood samples in Ho Chi Minh City, Vietnam.

Salmonellosis is a type of foodborne disease caused by Salmonella enterica and is a frequent cause of childhood diarrhea in Vietnam. Of particular concern is the dissemination of multidrug-resistant Salmonella, as extended-spectrum β-lactamase (ESBL)-positive isolates were recently detected in children in Vietnam. In the present study, the prevalence and antibiotic resistance of Salmonella isolates obtained from 409 raw meat and seafood samples collected between October 2012 and March 2015 from slaughterhouses, wholesale fish market, and retail markets in Ho Chi Minh City, Vietnam were examined.

Serine Protease Catalysis: A Computational Study of Tetrahedral Intermediates and Inhibitory Adducts.

Peptide boronic acids and peptidyl trifluoromethyl ketones (TFKs) inhibit serine proteases by forming monoanionic, tetrahedral adducts to serine in the active sites. Investigators regard these adducts as analogs of monoanionic, tetrahedral intermediates. Density functional theory (DFT) calculations and fractional charge analysis show that tetrahedral adducts of model peptidyl TFKs are structurally and electrostatically very similar to corresponding tetrahedral intermediates.

Effective management for acidic pollution in the canal network of the Mekong Delta of Vietnam: a modeling approach.

Acidic pollution can cause severe environmental consequences annually in coastal areas overlain with acid sulfate soils (ASS). A water quality model was used as an analytical tool for exploring the effects of water management options and other interventions on acidic pollution and salinity in Bac Lieu, a coastal province of the Mekong Delta. Fifty eight percent of the provincial area is covered by ASS, and more than three-fourths (approximately 175,000 ha) are used for brackish-water shrimp culture.