Cryo-EM structure of amyloid fibril formed by α-synuclein hereditary A53E mutation reveals a distinct protofilament interface.

Synucleinopathies like Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple systems atrophy (MSA), have the same pathologic feature of misfolded α-synuclein protein (α-syn) accumulation in the brain. PD patients who carry α-syn hereditary mutations tend to have earlier onset and more severe clinical symptoms than sporadic PD patients. Therefore, revealing the effect of hereditary mutations to the α-syn fibril structure can help us understand these synucleinopathies' structural basis.

A phage parasite deploys a nicking nuclease effector to inhibit viral host replication.

PLEs (phage-inducible chromosomal island-like elements) are phage parasites integrated into the chromosome of epidemic Vibrio cholerae. In response to infection by its viral host ICP1, PLE excises, replicates and hijacks ICP1 structural components for transduction. Through an unknown mechanism, PLE prevents ICP1 from transitioning to rolling circle replication (RCR), a prerequisite for efficient packaging of the viral genome.

An Enzyme-Mediated Amplification Strategy Enables Detection of β-Lactamase Activity Directly in Unprocessed Clinical Samples for Phenotypic Detection of β-Lactam Resistance.

Biochemical assays that can identify β-lactamase activity directly from patient samples have the potential to significantly improve the treatment of bacterial infections. However, current β-lactamase probes do not have the sensitivity needed to measure β-lactam resistance directly from patient samples. Here, we report the development of an instrument-free signal amplification technology, DETECT, that connects the activity of two enzymes in series to effectively amplify the activity of β-lactamase 40 000-fold, compared to the standard β-lactamase probe nitrocefin.

The benefits of high-potency fluoride dentifrices.

National surveys show that the incidence of caries in children, adults, and seniors is still quite high, despite interpretations to the contrary. The dental profession and general public agree that the standard level of 1,000 ppm to 1,500 ppm fluoride (F) in most dentifrices reduces dental caries. Many studies using higher concentrations of fluoride in dentifrices and gels, 2,000 to 5,000 ppm F, have shown that caries prevention increases with fluoride concentration.

Dietary models for root caries.

A stepwise multiple logistic regression was computed to assess which of the nutritional variables differentiate the healthy and diseased group of participants in the Forsyth Specialized Caries Center (n = 275). Variables considered as candidates for the model included the consumption per week of sugars, starch, cheese, fruits and fruit juices, noncariogenic foods, and dairy products. Two variables--sugars and cheese--were statistically significant by the stepwise procedure.