• Heller Carroll opublikował 1 rok, 3 miesiące temu

    While full integration of robotic surgery has been achieved in other surgical domains, its transition into neurosurgery has been more prolonged, especially with respect to pituitary surgery. The confined working space and precise maneuvers required in endoscopic endonasal surgery makes development of an efficacious and safe robotic system difficult. Nevertheless, preclinical studies have attempted to demonstrate the feasibility of the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA) in both transnasal and transoral approaches. In addition, unique robotics such as the concentric tube robot have been created. This system is optimized specifically for anterior skull base surgery with smaller shaft diameter arms and improved maneuverability in tight corridors. The possible role of concentric tube robotics surgery in skull base pathologies has been explored, and the novel use of telesurgery incorporated into robotic neurosurgery is discussed. An endoscopic endonasal transsphenoidal surgical system has also been developed, integrating computational methods to create a presurgical reconstructive model for surgical planning and automating the line of dissection for an enhanced approach to the sphenoid sinus. While surgical robotics for transsphenoidal surgery remain in its nascency, these preliminary findings are promising and suggest a role for robotic pituitary surgery.Three physiologically mineralizing tissues – teeth, cartilage and bone – have critical common elements and important evolutionary relationships. Phylogenetically the most ancient densely mineralized tissue is teeth. In jawless fishes without skeletons, tooth formation included epithelial transport of phosphates, a process echoed later in bone physiology. Cartilage and mineralized cartilage are skeletal elements separate from bone, but with metabolic features common to bone. Cartilage mineralization is coordinated with high expression of tissue nonspecific alkaline phosphatase and PHOSPHO1 to harvest available phosphate esters and support mineralization of collagen secreted locally. Mineralization in true bone results from stochastic nucleation of hydroxyapatite crystals within the cross-linked collagen fibrils. Mineral accumulation in dense collagen is, at least in major part, mediated by amorphous aggregates – often called Posner clusters – of calcium and phosphate that are small enough to diffuse into collagen fibrils. Mineral accumulation in membrane vesicles is widely suggested, but does not correlate with a definitive stage of mineralization. Conversely mineral deposition at non-physiologic sites where calcium and phosphate are adequate has been shown to be regulated in large part by pyrophosphate. All of these elements are present in vertebrate bone metabolism. A key biological element of bone formation is an epithelial-like cellular organization which allows control of phosphate, calcium and pH during mineralization.Patients with poorly controlled type 2 diabetes mellitus (T2DM) often experience delayed tooth extraction socket (TES) healing. Delayed healing is often associated with an aberrant inflammatory response orchestrated by either M1 pro-inflammatory or M2 anti-inflammatory macrophages. However, the precise mechanism for the attenuated TES healing remains unclear. Here we used diet-induced T2DM mice as a model to study TES. Compared with the control group, the T2DM group showed delayed TES healing and diminished expression of osteogenic and angiogenic genetic profiles. Meanwhile, we detected a more inflammatory profile, with more M1 macrophages and TNF-α expression and less M2 macrophages and PPARγ expression, in TES in the T2DM group when compared to control mice. In vitro co-culture models showed that M1 macrophages inhibited the osteogenic capacity of bone marrow stromal cells and the angiogenic capacity of endothelial cells while M2 macrophages showed an opposite effect. In addition, we constructed a gelatin/β-TCP scaffold with IL-4 to induce macrophage transformation towards M2 polarization. In vitro analyses of the hybrid scaffold revealed sustained release of IL-4 and a phenotype switch to M2 macrophages. Finally, we demonstrated that sustained IL-4 release significantly increased expression of osteogenic and angiogenic genetic profiles and improved TES healing in T2DM mice. Together, we report that increased M1 and decreased M2 macrophage polarization may be responsible for delayed TES healing in T2DM patients through abnormal expression of TNF-α and PPARγ. This imbalance negatively influences osteogenesis and angiogenesis, two of the most important biological factors in bone wound healing. Enhancing M2 macrophage polarization with IL-4 delivery system may represent a potential strategy for promoting the healing of TES in T2DM patients.Bone nonunion caused by bacterial infection accounts for bone fractures, bone trauma and bone transplantation surgeries. Severe consequences include delayed unions and amputation and result in functional limitations, work disability, and poor quality of life. However, the mechanism of bone nonunion remains unknown. In this study, we aimed to screen the miRNA biomarkers of bacterial bone infection and investigated whether miRNAs regulate the osteoblasts and thus contribute to bone nonunion. We established a miRNA-mRNA network based on high-throughput RNA sequencing to compare the model rabbits infected with Staphylococcus aureus with the control rabbits. After validation experiments, miRNA-331-3p and fibroblast growth factor 23 (FGF23) were found to be inversely correlated with the pathways of osteoblast mineralization and pathology of infected bone nonunion. In in vitro experiments, miRNA-331-3p was downregulated and FGF23 was upregulated in lipopolysaccharide (LPS)-induced mouse calvarial osteoblasts. Further studies of the mechanism showed that mutated of putative miRNA-331-3p can bind to FGF23 3′-untranslated region sites. MiRNA-331-3p acted as an osteoblast mineralization promoter by directly targeting FGF23. Downregulation of miRNA-331-3p led to inhibition of osteoblast mineralization by regulating the DKK1/β-catenin mediated signaling. Thus, we established an improved animal model and identified new bone-related biomarkers in the infected bone nonunion. The miRNA-331-3p biomarker was demonstrated to regulate osteoblast mineralization by targeting FGF23. The novel mechanism can be used as potential diagnostic biomarkers and therapeutic targets in the infected bone nonunion and other inflammatory bone disorders.To address the frequency of complex V defects, we systematically sequenced MT-ATP6/8 genes in 512 consecutive patients. We performed functional analysis in muscle or fibroblasts for 12 out of 27 putative homoplasmic mutations and in cybrids for four. Fibroblasts, muscle and cybrids with known deleterious mutations underwent parallel analysis. It included oxidative phosphorylation spectrophotometric assays, western blots, structural analysis, ATP production, glycolysis and cell proliferation evaluation. We demonstrated the deleterious nature of three original mutations. Striking gradation in severity of the mutations consequences and differences between muscle, fibroblasts and cybrids implied a likely under-diagnosis of human complex V defects.BACs-on-Beads (BoBs) assay and copy number variation sequencing (CNV-seq) are two frequently used methods in today’s prenatal diagnosis. Several studies were conducted to investigate the performance of each approach, but they were never compared side by side. In this article, a comprehensive comparison of BoBs and CNV-seq was conducted using 1876 amniotic fluid and umbilical cord blood samples collected from Fujian Provincial Maternity and Children’s Hospital between 2015 and 2019. Karyotyping was used as the gold standard for chromosome structure variation, and chromosomal microarray analysis was performed to validate inconsistent results. Overall, 174 cases of confirmed chromosome anomalies were detected, including 73 chromosomal aneuploidies, 10 mosaics, 30 pathogenic CNVs, and 61 other structural anomalies. BoBs and CNV-seq achieved a 100% concordance in all 55 pathogenic euchromosome aneuploidies, but CNV-seq had a higher detection rate in sex chromosome aneuploidy and mosaic identification. For CNV detection, all of the 20 pathogenic CNVs discovered by the BoBs assay also were identified by CNV-seq and 10 additional pathogenic CNVs were observed by CNV-seq. The results of this study showed that CNV-seq was a reliable and more favorable method in terms of detection rate, costs, and disease range. In combination with karyotyping, CNV-seq could improve the efficiency and accuracy of a prenatal diagnosis to alleviate maternal emotional anxiety and deduce birth defects.The detection and characterization of cell-free DNA (cfDNA) in peripheral blood from neuroblastoma patients may serve as a minimally invasive approach to liquid biopsy. Major challenges in the analysis of cfDNA purified from blood samples are small sample volumes and low cfDNA concentrations. Droplet digital PCR (ddPCR) is a technology suitable for analyzing low levels of cfDNA. Reported here are two quadruplexed ddPCR assay protocols that reliably quantify MYCN and ALK copy numbers in a single reaction together with the two reference genes, NAGK and AFF3, and accurately estimate ALKF1174L (exon 23 position 3522, C>A) and ALKR1275Q (exon 25 position 3824, G>A) mutant allele fractions using cfDNA as input. The separation of positive and negative droplets was optimized for detecting two targets in each ddPCR fluorescence channel by the adjustment of the probe and primer concentrations of each target molecule. The quadruplexed assays were validated using a panel of 10 neuroblastoma cell lines and paired blood plasma and primary neuroblastoma samples from nine patients. Accuracy and sensitivity thresholds in quadruplexed assays corresponded well with those from the respective duplexed assays. Presented are two robust quadruplexed ddPCR protocols applicable in the routine clinical setting and that require only minimal plasma volumes for the assessment of MYCN and ALK oncogene status.Tau is a microtubule-associated protein involved in Alzheimer’s disease. However, little is known on its physiological function in the healthy central nervous system. Here, we observed that the expression of Tau isoforms was modulated by neuronal maturation and visual experience in the mouse retina and in the visual cortex. The visual function of wild-type (WT) and Tau knockout (KO) mice was evaluated using the optokinetic reflex (OKR), an innate visuomotor behavior, and by electroretinography. Visual tests did not reveal functional impairments in young adult and old Tau KO animals. Moreover, monocular deprivation (MD) was used to increase OKR sensitivity, a plasticity phenomenon depending on the visual cortex. MD-induced OKR sensitivity enhancement was significantly stronger in Tau KO than in WT mice suggesting that Tau restricts visual plasticity. In addition, human Tau expression did not affect visual function and plasticity in a mouse tauopathy model, relative to WT controls. Our results unveil a novel function for Tau in the adaptive mechanisms of plasticity operating in the adult brain subjected to sensory experience changes.

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