The structure of tyrosine-10 favors ionic conductance of Alzheimer's disease-associated full-length amyloid-β channels.

Amyloid β (Aβ) ion channels destabilize cellular ionic homeostasis, which contributes to neurotoxicity in Alzheimer's disease. The relative roles of various Aβ isoforms are poorly understood. We use bilayer electrophysiology, AFM imaging, circular dichroism, FTIR and fluorescence spectroscopy to characterize channel activities of four most prevalent Aβ peptides, Aβ, Aβ, and their pyroglutamylated forms (AβpE, AβpE) and correlate them with the peptides' structural features.

Rapid self-test of unprocessed viruses of SARS-CoV-2 and its variants in saliva by portable wireless graphene biosensor.

We have developed a DNA aptamer-conjugated graphene field-effect transistor (GFET) biosensor platform to detect receptor-binding domain (RBD), nucleocapsid (N), and spike (S) proteins, as well as viral particles of original Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) coronavirus and its variants in saliva samples. The GFET biosensor is a label-free, rapid (≤20 min), ultrasensitive handheld wireless readout device. The limit of detection (LoD) and the limit of quantitation (LoQ) of the sensor are 1.

Scavenging amyloid oligomers from neurons with silica nanobowls: Implications for amyloid diseases.

Amyloid-β (Aβ) oligomers are toxic species implicated in Alzheimer's disease (AD). The prevailing hypothesis implicates a major role of membrane-associated amyloid oligomers in AD pathology. Our silica nanobowls (NB) coated with lipid-polymer have submicromolar affinity for Aβ binding.

Cutting mechanics of wood by beetle larval mandibles.

Wood boring is a feature of several insect species and is a major cause of severe and irreparable damage to trees. Adult females typically deposit their eggs on the stem surface under bark scales. The emerging hatchlings live within wood during their larval phase, avoiding possible predation, whilst continually boring and tunneling through wood until pupation.

Ion channel formation by N-terminally truncated Aβ (4-42): relevance for the pathogenesis of Alzheimer's disease.

Aβ deposition is a pathological hallmark of Alzheimer's disease (AD). Besides the full-length amyloid forming peptides (Aβ and Aβ), biochemical analyses of brain deposits have identified a variety of N- and C-terminally truncated Aβ variants in sporadic and familial AD patients. However, their relevance for AD pathogenesis remains largely understudied.

DNA Nanotweezers and Graphene Transistor Enable Label-Free Genotyping.

Electronic DNA-biosensor with a single nucleotide resolution capability is highly desirable for personalized medicine. However, existing DNA-biosensors, especially single nucleotide polymorphism (SNP) detection systems, have poor sensitivity and specificity and lack real-time wireless data transmission. DNA-tweezers with graphene field effect transistor (FET) are used for SNP detection and data are transmitted wirelessly for analysis.

Gelatin Methacrylate Hydrogels as Biomimetic Three-Dimensional Matrixes for Modeling Breast Cancer Invasion and Chemoresponse in Vitro.

Recent studies have shown that three-dimensional (3D) culture environments allow the study of cellular responses in a setting that more closely resembles the in vivo milieu. In this context, hydrogels have become popular scaffold options for the 3D cell culture. Because the mechanical and biochemical properties of culture matrixes influence crucial cell behavior, selecting a suitable matrix for replicating in vivo cellular phenotype in vitro is essential for understanding disease progression.