Pressure fluctuations as well as supple moduli within disordered solids

The key role of APP for Alzheimer pathogenesis is well established. However, perinatal lethality of germline knockout mice lacking the entire APP family has so far precluded the analysis of its physiological functions for the developing and adult brain. Here, we generated conditional APP/APLP1/APLP2 triple KO (cTKO) mice lacking the APP family in excitatory forebrain neurons from embryonic day 11.5 onwards. NexCre cTKO mice showed altered brain morphology with agenesis of the corpus callosum and disrupted hippocampal lamination. Further, NexCre cTKOs revealed reduced basal synaptic transmission and drastically reduced long-term potentiation that was associated with reduced dendritic length and reduced spine density of pyramidal cells. With regard to behavior, lack of the APP family leads not only to severe impairments in a panel of tests for learning and memory, but also to an autism-like phenotype including repetitive rearing and climbing, impaired social communication, and deficits in social interaction. Together, our study identifies essential functions of the APP family during development, for normal hippocampal function and circuits important for learning and social behavior.Cisplatin resistance is a major clinical problem in the clinical management of oral squamous cell carcinoma (OSCC) patients. Resveratrol is a natural phytoestrogen with antitumor activities. Whether resveratrol can overcome cisplatin resistance and prevent metastasis in OSCC cells is not known. In this study, we first examined the anti-metastatic capacity of resveratrol and then explored the underlying mechanisms using a cisplatin-resistant human OSCC cell line (CAR). The results demonstrated that at a non-toxic dose range (25 to 75 µM), 24-hr treatment of resveratrol was able to suppress the migration and invasion capacities of CAR cells dose dependently. Interestingly, 50 µM resveratrol treatment could significantly down-regulate the expression of the phosphorylated forms of ERK and p-38, in addition to those of MMP-2 and MMP-9. At the same time, the expression levels of phosphorylated ERK together with those unphosphorylated forms of ERK, p38, and JNK were all insignificantly altered. In conclusion, the signaling cascade for resveratrol's suppression of cisplatin-resistant human oral cancer CAR cells was revealed and summarized. Also the rapid effectiveness in suppressing metastatic behaviors of drug-resistant oral cancer cells of non-toxic resveratrol might extend its application to the drug-resistant oral cancer treatment in the near future. PRACTICAL APPLICATIONS Based on the evidence we provided in the study, we have proposed a model recording the possible pathway for resveratrol inhibiting the metastasis of cisplatin-resistant oral cancer cells. We suppose this signaling pathway may work in other cancer cell lines, and can be helpful in full understanding of the drug-resistance.
Using the rat sciatic nerve model, sliced nerves of different thickness was combined to a biodegradable nerve conduit and the amount of nerve fragment necessary to promote nerve regeneration was investigated.
Harvested sciatic nerve (n=6) was processed in sliced nerve of the different width; 2, 1, 0.5 mm, respectively. Western blot analysis was carried out to determine protein expression of Erk1/2. Subsequently, a total of 246 rats were used to create a 10 mm gap in the sciatic nerve. A polyglycolic acid-based nerve conduit was used to bridge the gap, with one sliced (width; 2, 1, 0.5 mm) or two (width; 1 mm × 2) incorporated within the conduit (n=6 at each point in each group). At 2, 4, 8, and 20 weeks after surgery, samples were resected and subjected to immune-histological, transmission electron microscopic, and motor functional evaluation for nerve regeneration.
Western blot analysis demonstrated Erk1/2 expressions were significantly increased in the groups of 2-mm and 1-mm width and attenuated in the 0.5-mm width group (p < .05). The immune-histological study showed the migration of Schwann cells and axon elongation were significantly extended in the groups of 2-mm, 1-mm, and 1 mm × 2 width at 4 weeks (p < .01), in which nerve conduction velocity was marked at 20 weeks (p < .01) after implantation.
When nerve tissue was inserted in the biodegradable nerve conduit as a sliced nerve, the method of inserting two sheets with a slice width of 1 mm most strongly accelerated motor function.
When nerve tissue was inserted in the biodegradable nerve conduit as a sliced nerve, the method of inserting two sheets with a slice width of 1 mm most strongly accelerated motor function.α-Conotoxins are small disulfide-rich peptides found in the venom of marine cone snails and are potent antagonists of nicotinic acetylcholine receptors (nAChRs). They are valuable pharmacological tools and have potential therapeutic applications for the treatment of chronic pain or neurological diseases and disorders. In the present study, we synthesized and functionally characterized a novel α-conotoxin Bt1.8, which was cloned from Conus betulinus. Bt1.8 selectively inhibited ACh-evoked currents in Xenopus oocytes expressing rat(r) α6/α3β2β3 and rα3β2 nAChRs with an IC50 of 2.1 nM and 9.4 nM, respectively, and similar potency for human (h) α6/α3β2β3 and hα3β2 nAChRs. Additionally, Bt1.8 had higher binding affinity with a slower dissociation rate for the rα6/α3β2β3 subtype compared to rα3β2. The amino acid sequence of Bt1.8 is significantly different from other reported α-conotoxins targeting the two nAChR subtypes. Further Alanine scanning analyses demonstrated that residues Ile9, Leu10, Asn11, Asn12 and Asn14 are critical for its inhibitory activity at the α6/α3β2β3 and α3β2 subtypes. Moreover, the NMR structure of Bt1.8 indicated the presence of a relatively larger hydrophobic zone than other α4/7-conotoxins which may explain its potent inhibition at α6/α3β2β3 nAChRs.
Cortical hyperexcitability is a feature of amyotrophic lateral sclerosis (ALS) and cortical excitability can be measured using transcranial magnetic stimulation (TMS). Resting motor threshold (MT) is a measure of cortical excitability, largely driven by glutamate. Perampanel, a glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor blocker, is predicted to increase the cortical excitability threshold. This study aimed to evaluate TMS to functionally assess target engagement in a study of perampanel in ALS.
We studied the MT of ALS patients randomized to a single dose of perampanel or placebo 51 hourly for 4h. Twelve patients participated at 4mg and 7 returned for dosing and retesting at 8mg. The study was terminated in April 2020 due to coronavirus disease 2019-related restrictions, after 7 out of 12 planned patients had received the 8mg dose. Serum concentrations were also measured.
Ten patients received the 4mg dose (2 received placebo) and 5 received the 8mg dose (2 received placebo). Motor Threshold increased at 2h after dosing in the combined treatment group +7% of maximal stimulator output (P< .01). Change could be detected in the larger 4mg group (P= .02), but not in the smaller 8mg dose group (P= .1). No side effects were reported after single dose exposure.
This study shows that perampanel effects the physiology of upper motor neurons. Studies aiming at gauging the effect of perampanel on ALS disease progression are already ongoing. Motor threshold may serve as a marker of biological target engagement.
This study shows that perampanel effects the physiology of upper motor neurons. Studies aiming at gauging the effect of perampanel on ALS disease progression are already ongoing. Motor threshold may serve as a marker of biological target engagement.
In our previous study, it has been confirmed that formaldehyde (FA) not only inhibits the proliferative activity, but also causes DNA-protein crosslinks (DPCs) formation in bone marrow mesenchymal stem cells (BMSCs). The purpose of this study was to detect the protective effect of astragalus polysaccharide (APS) against the cytotoxicity and genotoxicity of BMSCs exposed to FA, and to explore potential molecular mechanisms of APS activity.
Human BMSCs were cultured in vitro and randomly divided into control cells (Ctrl group), FA-treated cells (FA group, 120 μmol/L), and cells incubated with FA and increasing concentrations (40, 100, or 400 μg/mL) of APS (FA + APS groups). Cytotoxicity was measured by MTT assay. DNA strand breakage, DNA-protein crosslinks (DPCs), and micronucleus formation were respectively detected by comet assay, KCl-SDS precipitation assay, and micronucleus assay. The mRNA and protein expression level of xeroderma pigmentosum group A (XPA), xeroderma pigmentosum group C (XPC), excision excision repair (NER) pathway which promotes DNA damage repair.Marrow stimulation, including subchondral drilling and microfracture, is the most commonly performed cartilage repair strategy, whereby the subchondral bone plate is perforated to release marrow-derived cells into a cartilage defect to initiate repair. Novel scaffolds and therapeutics are being designed to enhance and extend the positive short-term outcomes of this marrow stimulation. However, the translation of these newer treatments is hindered by bony abnormalities, including bone resorption, intralesional osteophytes, and bone cysts, that can arise after marrow stimulation. In this study, three different marrow stimulation approaches - microfracture, subchondral drilling and needle-puncture - were evaluated in a translationally relevant large-animal model, the Yucatan minipig. The objective of the study was to determine which method of marrow access (malleted awl, drilled Kirschner wire or spring-loaded needle) best preserved the underlying subchondral bone. Fluorochrome labels were injected at the time of surgery and 2 weeks post-surgery to capture bone remodelling over the first 4 weeks. Comprehensive outcome measures included cartilage indentation testing, histological grading, microcomputed tomography and fluorochrome imaging. Findings indicated that needle-puncture devices best preserved the underlying subchondral bone relative to other marrow access approaches. This may relate to the degree of bony compaction occurring with marrow access, as the Kirschner wire approach, which consolidated bone the most, induced the most significant bone damage with marrow stimulation. This study provided basic scientific evidence in support of updated marrow stimulation techniques for preclinical and clinical practice.The objectives of this study are to experimentally investigate the effects of the dielectric material and the package stiffness on the durability and the efficiency of a previously developed triboelectric-based instrumented knee implant prototype. The proposed smart knee implant may provide useful information about prosthesis health and its functionality after a total knee replacement (TKR) by routine monitoring of tibiofemoral load transfer without the need for any external power source. The triboelectric powered load sensing by the proposed TKR system needs to be functional throughout the entire life of a knee replacement. The power output of the triboelectric system depends on the surface charge generations and accumulations on its dielectric material, and the force that transmits through its housing into the tribo-materials. YM155 cost The properties of the dielectric material and the package stiffness can significantly influence the reliability of the proposed device. For such a TKR system, a compliant mechanism with the ideal material selection can improve its state of the art.