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Meincke Woodward posted an update 10 hours, 31 minutes ago
Pathological hyperphosphorylated tau is a key feature of Alzheimer’s disease (AD) and Frontotemporal dementia (FTD). Using transgenic mice overexpressing human non-mutated tau (htau mice), we assessed the contribution of tau to peripheral and central neurodegeneration. Indices of peripheral small and large fiber neuropathy and learning and memory performances were assessed at 3 and 6 months of age. Overexpression of human tau is associated with peripheral neuropathy at 6 months of age. Our study also provides evidence that non-mutated tau hyperphosphorylation plays a critical role in memory deficits. In addition, htau mice had reduced stromal corneal nerve length with preservation of sub-basal corneal nerves, consistent with a somatofugal degeneration. Corneal nerve degeneration occurred prior to any cognitive deficits and peripheral neuropathy. Stromal corneal nerve loss was observed in patients with FTD but not AD. Corneal confocal microscopy may be used to identify early neurodegeneration and differentiate FTD from AD.Abnormalities in thyroid hormones (TH) availability and/or metabolism have been hypothesized to contribute to Alzheimer’s disease (AD) and to be a risk factor for stroke. Recently, 3-iodothyronamine (T1AM), an endogenous amine putatively derived from TH metabolism, gained interest for its ability to promote learning and memory in the mouse. Moreover, T1AM has been demonstrated to rescue the β-Amyloid dependent LTP impairment in the entorhinal cortex (EC), a brain area crucially involved in learning and memory and early affected during AD. In the present work, we have investigated the effect of T1AM on ischemia-induced EC synaptic dysfunction. In EC brain slices exposed to oxygen-glucose deprivation (OGD), we demonstrated that the acute perfusion of T1AM (5 μM) was capable of preventing ischemia-induced synaptic depression and that this protective effect was mediated by the trace amine-associated receptor 1 (TAAR1). Moreover, we demonstrated that activation of the BDNF-TrkB signalling is required for T1AM action during ischemia. The protective effect of T1AM was more evident when using EC slices from transgenic mutant human APP (mhAPP mice) that are more vulnerable to the effect of OGD. Our results confirm that the TH derivative T1AM can rescue synaptic function after transient ischemia, an effect that was also observed in a Aβ-enriched environment.REC8 (meiotic recombination protein 8) is an essential component of meiotic cohesion complexes. Interestingly, two paralogous rec8 genes happen to exist in the stra8 (stimulated by retinoic acid gene 8)-absent fishes but not in stra8-existing fishes. Stra8 is usually considered as the prerequirement during RA (retinoic acid)-mediated meiosis initiation in mammals. However, how RA triggers meiosis in the stra8-absent fishes just like Nile tilapia (Oreochromis niloticus) remains elusive. Here we characterized the two paralogous rec8 genes in Nile tilapia (Onrec8a and Onrec8b), and investigated their expression patterns and responsiveness to RA signaling by treatment of ex vivo testicular culture and promoter luciferase reporter assay. OnRec8a and OnRec8b share 36% identity to each other and are true orthologs of REC8. Their expression was predominantly restricted to meiotic germline cells with differential spatiotemporal patterns. A-769662 order During spermatogenesis, OnRec8b predominantly exhibited nuclear expression in spermatocytes from 60 dah (days after hatching), while OnRec8a exhibited cytoplasmic expression from 90 dah. During oogenesis, OnRec8a was expressed from 30 dah, while OnRec8b from 90 dah. Further study shows that RA signaling could upregulate the expression of both Onrec8a and Onrec8b. Collectively, our data implies that OnRec8a and OnRec8b might have differential function during meiosis and be involved in RA-mediated meiosis program.
To evaluate longitudinally the persistence of humoral immunity for up to 6months in a cohort of hospital employees with mild coronavirus disease 2019 (COVID-19).
We measured anti-RBD (receptor binding domain of viral spike protein), anti-N (viral nucleoprotein) and neutralizing antibodies at 1, 3 and 6months after mostly mild COVID-19 in 200 hospital workers using commercial ELISAs and a surrogate virus neutralization assay.
Antibodies specific for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) persisted in all participants for up to 6months. Anti-RBD geometric mean concentrations (GMCs) progressively increased between months 1 (74.2 U/mL, 95%CI 62.7-87.8), 3 (103.2 U/mL, 95%CI 87.9-121.2; p<0.001), and 6 (123.3 U/mL, 95%CI 103.4-147.0; p<0.001) in the whole cohort. Anti-N antibodies were detectable in >97% at all times. Neutralizing antibodies were detectable in 99.5% of participants (195/196) at 6months post infection. Their GMC progressively decreased between months 1 (20.1 AU/mL, 95%CI 16.9-24.0), 3 (15.2 AU/mL, 95%CI 13.2-17.6; p<0.001) and 6 (9.4 AU/mL, 95%CI 7.7-11.4; p<0.001). RBD-ACE2-inhibiting antibody titres and anti-RBD antibody concentrations strongly correlated at each timepoint (all r>0.86, p<0.001). Disease severity was associated with higher initial anti-RBD and RBD-ACE2-inhibiting antibody titres, but not with their kinetics.
Neutralizing antibodies persisted at 6months in almost all participants, indicating more durability than initially feared. Anti-RBD antibodies persisted better and even increased over time, possibly related to the preferential detection of progressively higher-affinity antibodies.
Neutralizing antibodies persisted at 6 months in almost all participants, indicating more durability than initially feared. Anti-RBD antibodies persisted better and even increased over time, possibly related to the preferential detection of progressively higher-affinity antibodies.Dissemination of cancer cells is an intricate multistep process that represents the most deadly aspect of cancer. Cancer cells form F-actin-rich protrusions known as invadopodia to invade surrounding tissues, blood vessels and lymphatics. A number of studies have demonstrated the significant roles of invadopodia in cancer. Therefore, the specific cells and molecules involved in invadopodia activity can provide as therapeutic targets. In this review, we included a thorough overview of studies in invadopodia and discussed their functions in cancer metastasis. We then presented the specific cells and molecules involved in invadopodia activity in pancreatic cancer and analyzed their suitability to be effective therapeutic targets. Currently, drugs targeting invadopodia and relevant clinical trials are negligible. Here, we highlighted the significance of potential drugs and discussed future obstacles in implementing clinical trials. This review presents a new perspective on invadopodia-induced pancreatic cancer metastasis and may prosper the development of targeted therapeutics against pancreatic cancer.