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  • McGinnis Raymond posted an update 1 day, 4 hours ago

    α-Synuclein, the major constituent of Lewy bodies (LBs), is normally expressed in presynapses and is involved in synaptic function. Abnormal intracellular aggregation of α-synuclein is observed as LBs and Lewy neurites in neurodegenerative disorders, such as Parkinson’s disease (PD) or dementia with Lewy bodies. PKC activator Accumulated evidence suggests that abundant intracellular expression of α-synuclein is one of the risk factors for pathological aggregation. Recently, we reported differential expression patterns of α-synuclein between excitatory and inhibitory hippocampal neurons. Here we further investigated the precise expression profile in the adult mouse brain with special reference to vulnerable regions along the progression of idiopathic PD. The results show that α-synuclein was highly expressed in the neuronal cell bodies of some early PD-affected brain regions, such as the olfactory bulb, dorsal motor nucleus of the vagus, and substantia nigra pars compacta. Synaptic expression of α-synuclein was mostly accompanied by expression of vesicular glutamate transporter-1, an excitatory presynaptic marker. In contrast, expression of α-synuclein in the GABAergic inhibitory synapses was different among brain regions. α-Synuclein was clearly expressed in inhibitory synapses in the external plexiform layer of the olfactory bulb, globus pallidus, and substantia nigra pars reticulata, but not in the cerebral cortex, subthalamic nucleus, or thalamus. These results suggest that some neurons in early PD-affected human brain regions express high levels of perikaryal α-synuclein, as happens in the mouse brain. Additionally, synaptic profiles expressing α-synuclein are different in various brain regions.Type I interferon (IFN) production plays pivotal roles in host antiviral innate immune responses, but an excessive production of type I IFN leads to the development of immunopathological conditions. Investigations on the regulatory mechanisms underlying host type I IFN production are currently of great interest. Here, we found that the expression of lectin family member Siglec1 was upregulated by viral infection in macrophages, which was dependent on the IFN/JAK/STAT1 signaling pathway. link2 Siglec1 was found to negatively regulate viral infection-triggered type I IFN production. Mechanistically, Siglec1 associates with DAP12 to recruit and activate the scaffolding function of SHP2; SHP2 then recruits E3 ubiquitin ligase TRIM27, which induces TBK1 degradation via K48-linked ubiquitination at Lys251 and Lys372. Therefore, viral infection-induced upregulation of Siglec1 feedback loop inhibits type I IFN production and suppresses antiviral innate immune responses. Our study outlines a novel mechanism of negative regulation of type I IFN production, which may help virus to escape immune elimination.In vertebrates, embryonic hematopoietic stem and progenitor cells (HSPCs) are derived from a subset of endothelial cells, the hemogenic endothelium (HE), through the endothelial-to-hematopoietic transition (EHT). Notch signaling is essential for HSPC development during embryogenesis across vertebrates. However, whether and how it regulates EHT remains unclear. Here, we show that G protein-coupled receptor 183 (Gpr183) signaling serves as an indispensable switch for HSPC emergence by repressing Notch signaling before the onset of EHT. Inhibition of Gpr183 significantly upregulates Notch signaling and abolishes HSPC emergence. Upon activation by its ligand 7α-25-OHC, Gpr183 recruits β-arrestin1 and the E3 ligase Nedd4 to degrade Notch1 in specified HE cells and then facilitates the subsequent EHT. Importantly, 7α-25-OHC stimulation promotes HSPC emergence in vivo and in vitro, providing an attractive strategy for enhancing the in vitro generation of functional HSPCs.Anticancer therapeutics aimed at the inhibition of mTORC1 activity shift metabolism to favor the degradation of extracellular proteins. Recently Thompson and colleagues demonstrated a novel regulatory mechanism whereby mTORC1 plays a distinct role as a key regulator of metabolism depending on the environmental nutrient status.Two proteolytic enzymes, β- and γ-secretases, work together to produce the amyloid β-peptide of Alzheimer’s disease. New evidence suggests that these proteases directly interact and compounds that disrupt this interaction reduce amyloid β-peptide levels without directly blocking either enzyme’s solo activity.Cardiac injury in neonatal 1-day-old mice stimulates a regenerative response characterized by reactive cardiomyocyte proliferation, which is distinguished from the fibrotic repair process in adults. Acute inflammation occurs immediately after heart injury and has generally been believed to exert a negative effect on heart regeneration by promoting scar formation in adults; however, little is known about the role of acute inflammation in the cardiac regenerative response in neonatal mice. Here, we show that acute inflammation induced cardiomyocyte proliferation after apical intramyocardial microinjection of immunogenic zymosan A particles into the neonatal mouse heart. We also found that cardiac injury-induced regenerative response was suspended after immunosuppression in neonatal mice, and that cardiomyocytes could not be reactivated to proliferate after neonatal heart injury in the absence of interleukin-6 (IL-6). Furthermore, cardiomyocyte-specific deletion of signal transducer and activator of transcription 3 (STAT3), the major downstream effector of IL-6 signaling, decreased reactive cardiomyocyte proliferation after apical resection. Our results indicate that acute inflammation stimulates the regenerative response in neonatal mouse heart, and suggest that modulation of inflammatory signals might have important implications in cardiac regenerative medicine.

    Vancomycin and ciprofloxacin were often used in the therapy of infections associated with Bacillus cereus.

    Four B. cereus food and clinical isolates were chosen for determination of time-kill curves and postantibiotic effects (PAE) of ciprofloxacin and vancomycin.

    According to the minimum inhibition concentration (MIC), breakpoints defined by CLSI for Staphylococcus spp. were all four strains intermediate for vancomycin (MIC = 4 μg/ml) and sensitive to ciprofloxacin (MIC = 0.2 μg/ml) except the strain Bc63 resistant to the last antimicrobial (MIC = 1.6 μg/ml). The lowest CFU values of tested strains were reached after 3-5 hours of exposure to 4 ×  MIC of vancomycin, and after 6-7 hours exposure to 10 ×  MIC of ciprofloxacin. The maximum reduction of the CFU in the presence of vancomycin and ciprofloxacin was about 2.46 log10 and 2.48 log10, respectively. The average duration of the PAE of vancomycin and ciprofloxacin was 0.94 and 1.60 hours, respectively. The statistically significant differences between PAEs induced with 3 ×  MIC, 4 ×  MIC and 8 ×  MIC of vancomycin were observed (P < 0.05). Both antibiotics did not affect the sporulation of tested bacterial strains.

    The differences in PAE duration were strain and antimicrobial dependent.

    The differences in PAE duration were strain and antimicrobial dependent.Topaz1 (Testis and Ovary-specific PAZ domain gene 1) is a germ cell specific gene highly conserved in vertebrates. The putative protein TOPAZ1 contains a PAZ domain, specifically found in PIWI, Argonaute and Zwille proteins. Consequently, Topaz1 is supposed to have a role during gametogenesis and may be involved in the piRNA pathway and contribute to silencing of transposable elements and maintenance of genome integrity. Here we report Topaz1 inactivation in mouse. Female fertility was not affected, but male sterility appeared exclusively in homozygous mutants in accordance with the high expression of Topaz1 in male germ cells. Pachytene Topaz1–deficient spermatocytes progress through meiosis without either derepression of retrotransposons or MSCI dysfunction, but become arrested before the post-meiotic round spermatid stage with extensive apoptosis. Consequently, an absence of spermatids and spermatozoa was observed in Topaz1(-/-) testis. Histological analysis also revealed that disturbances of spermatogenesis take place between post natal days 15 and 20, during the first wave of male meiosis and before the generation of haploid germ cells. Transcriptomic analysis at these two stages showed that TOPAZ1 influences the expression of one hundred transcripts, most of which are up-regulated in mutant testis at post natal day 20. Our results also showed that 10% of these transcripts are long non-coding RNA. This suggests that a highly regulated balance of lncRNAs seems to be essential during spermatogenesis for induction of appropriate male gamete production.While breast cancer has not historically been considered an immunogenic cancer, recent data demonstrating the powerful anti-cancer effects of immune checkpoints in many cancers, including breast cancer, has reinvigorated the field. Although the responses are generally low with single agents, some patients experience disease control for a long period of time. Selecting appropriate patients for immunotherapy is an important area of research, and many biomarkers are under investigation. Although immunotherapies are still in their early stages of development, learning how to use them in combination with other agents that can alter antigen presentation or other immune elements will be crucial. This review aims to summarize efforts in immune-related biomarker and drug development, particularly as it pertains to breast cancer.The short average service life of traditional dental composite restorative materials and increasing occurrence of secondary caries adjacent to composite restorations and sealants are necessitating the development of new, longer lasting compositions. Novel monomers and their polymers, reinforcing fillers, and adhesive components are needed. link3 The goal of this research is to develop resin systems for use in restorations, sealants, and other dental services that are superior in properties and endurance to currently used bisphenol A glycidyl dimethacrylate/triethylene glycol dimethacrylate (Bis-GMA/TEGDMA) and urethane-dimethacrylate products. Ether-based monomers and their polymers that were not susceptible to enzymatic or hydrolytic degradation were prepared and characterized. They showed no degradation under hydrolytic and enzymatic challenges, whereas the hydrolysis of ester links weakened contemporary resins within 16 days under these challenges. The success of the ether-based materials is promising in making durable systems that are subjected to long-term biochemical and hydrolytic challenges in oral environments.

    Tachyphylaxis or acute tolerance to local anaesthetics has been reported, but the prevalence in clinical analgesia is obscure, and the mechanisms behind this phenomenon remain unclear. We sought to examine the clinical significance of tachyphylaxis from the available literature.

    We performed a systematic review of the literature utilising the databases PubMed and Embase employing the search terms [Tachyphylaxis AND Local Anaesthetics AND Human] AND [Tolerance AND Local Anaesthetics AND Human].

    A total of 66 records were identified. Thirty-four articles were assessed in full text for eligibility. Twenty studies were considered relevant for qualitative analyses, but only six studies were randomised controlled trials. Because of the heterogeneity of the randomised controlled trials, it was not possible to conduct a meta-analysis.

    Studies documenting tachyphylaxis with clinical use of local anaesthetics are surprisingly scarce, and the mechanisms behind it remain unclear.

    Studies documenting tachyphylaxis with clinical use of local anaesthetics are surprisingly scarce, and the mechanisms behind it remain unclear.