Downregulation of the RNA-binding protein PUM2 facilitates MSC-driven bone regeneration and prevents OVX-induced bone loss.

BACKGROUND: Although mRNA dysregulation can induce changes in mesenchymal stem cell (MSC) homeostasis, the mechanisms by which post-transcriptional regulation influences MSC differentiation potential remain understudied. PUMILIO2 (PUM2) represses translation by binding target mRNAs in a sequence-specific manner. METHODS: In vitro osteogenic differentiation assays were conducted using human bone marrow-derived MSCs. Alkaline phosphatase and alizarin red S staining were used to evaluate the osteogenic potential of MSCs. A rat xenograft model featuring a calvarial defect to examine effects of MSC-driven bone regeneration. RNA-immunoprecipitation (RNA-IP) assay was used to determine the interaction between PUM2 protein and Distal-Less Homeobox 5 (DLX5) mRNA. Ovariectomized (OVX) mice were employed to evaluate the effect of gene therapy for postmenopausal osteoporosis. RESULTS: Here, we elucidated the molecular mechanism of PUM2 in MSC osteogenesis and evaluated the applicability of PUM2 knockdown (KD) as a potential cell-based or gene therapy. PUM2 level was downregulated during MSC osteogenic differentiation, and PUM2 KD enhanced MSC osteogenic potential. Following PUM2 KD, MSCs were transplanted onto calvarial defects in 12-week-old rats; after 8 weeks, transplanted MSCs promoted bone regeneration. PUM2 KD upregulated the expression of DLX5 mRNA and protein and the reporter activity of its 3'-untranslated region. RNA-IP revealed direct binding of PUM2 to DLX5 mRNA. We then evaluated the potential of adeno-associated virus serotype 9 (AAV9)-siPum2 as a gene therapy for osteoporosis in OVX mice. CONCLUSION: Our findings suggest a novel role for PUM2 in MSC osteogenesis and highlight the potential of PUM2 KD-MSCs in bone regeneration. Additionally, we showed that AAV9-siPum2 is a potential gene therapy for osteoporosis.

Deubiquitinating Enzyme USP7 Is Required for Self-Renewal and Multipotency of Human Bone Marrow-Derived Mesenchymal Stromal Cells.

Ubiquitin-specific protease 7 (USP7) is highly expressed in a variety of malignant tumors. However, the role of USP7 in regulating self-renewal and differentiation of human bone marrow derived mesenchymal stromal cells (hBMSCs) remains unknown. Herein, we report that USP7 regulates self-renewal of hBMSCs and is required during the early stages of osteogenic, adipogenic, and chondrogenic differentiation of hBMSCs. USP7, a deubiquitinating enzyme (DUB), was found to be downregulated during hBMSC differentiation. Furthermore, USP7 is an upstream regulator of the self-renewal regulating proteins SOX2 and NANOG in hBMSCs. Moreover, we observed that SOX2 and NANOG are poly-ubiquitinated and their expression is downregulated in USP7-deficient hBMSCs. Overall, this study showed that USP7 is required for maintaining self-renewal and multipotency in cultured hBMSCs. Targeting USP7 might be a novel strategy to preserve the self-renewal capacity of hBMSCs intended for stem cell therapy.

Cellular and Tissue Selectivity of AAV Serotypes for Gene Delivery to Chondrocytes and Cartilage.

Background: Despite several studies on the effect of adeno-associated virus (AAV)-based therapeutics on osteoarthritis (OA), information on the transduction efficiency and applicable profiles of different AAV serotypes to chondrocytes in hard cartilage tissue is still limited. Moreover, the recent discovery of additional AAV serotypes makes it necessary to screen for more suitable AAV serotypes for specific tissues. Here, we compared the transduction efficiencies of 14 conventional AAV serotypes in human chondrocytes, mouse OA models, and human cartilage explants obtained from OA patients. Methods: To compare the transduction efficiency of individual AAV serotypes, green fluorescent protein (GFP) expression was detected by fluorescence microscopy or western blotting. Likewise, to compare the transduction efficiencies of individual AAV serotypes in cartilage tissues, GFP expression was determined using fluorescence microscopy or immunohistochemistry, and GFP-positive cells were counted. Results: Only AAV2, 5, 6, and 6.2 exhibited substantial transduction efficiencies in both normal and OA chondrocytes. All AAV serotypes except AAV6 and rh43 could effectively transduce human bone marrow mesenchymal stem cells. In human and mouse OA cartilage tissues, AAV2, AAV5, AAV6.2, AAV8, and AAV rh39 showed excellent tissue specificity based on transduction efficiency. These results indicate the differences in transduction efficiencies of AAV serotypes between cellular and tissue models. Conclusions: Our findings indicate that AAV2 and AAV6.2 may be the best choices for AAV-mediated gene delivery into intra-articular cartilage tissue. These AAV vectors hold the potential to be of use in clinical applications to prevent OA progression if appropriate therapeutic genes are inserted into the vector.

Age shock index, shock index, and modified shock index for predicting postintubation hypotension in the emergency department.

INTRODUCTION: Hypotension after emergent ETI is a relatively common complication during and after emergency airway management. We aimed to evaluate SI, MSI, and age SI to predict PIH in patients who presented to the emergency department. Moreover, which factors would be better for predicting the event or similar to the others. METHODS: A retrospective, standardized chart review of consecutive ED patients requiring intubation at an urban, tertiary-care teaching hospital, from January 2011 to December 2016. PIH was defined as any recorded SBP <90 mmHg or MAP <65 mmHg within the 60-minute period after intubation. RESULTS: Hypotension after emergent ETI was observed in 130 (29.7%) patients. The ROC-AUC of age SI, MSI, and SI before intubation for prediction of PIH were 0.676 (95% CI 0.63-0.72), 0.614 (95% CI 0.567-0.66), and 0.611 (95% CI 0.564-0.657). The prognostic performance of age SI for prediction of PIH was better than MSI and SI (p = 0.006 for age SI versus MSI, p = 0.005 for age SI versus SI). CONCLUSIONS: Preintubation age SI, MSI, and SI are all independent predictors of PIH in patients who need emergent intubation. Aong these parameters, age SI is the best marker to predict the outcome. Calculation of these indexes are simple and could be an guide of implement to prevent hypotension after ETI.

Prehospital advanced cardiac life support by EMT with a smartphone-based direct medical control for nursing home cardiac arrest.

OBJECTIVE: To compare the survival to discharge between nursing home (NH) cardiac arrest patients receiving smartphone-based advanced cardiac life support (SALS) and basic life support (BLS). METHODS: The SALS registry includes data on cardiac arrest from 7 urban and suburban areas in Korea between July 2015 and December 2016. We include adult patients (>18) with out-of-hospital cardiac arrest (OHCA) of medical causes and EMS attended and dispatched in. SALS is an advanced field resuscitation including drug administration by paramedics with video communication-based direct medical direction. Prehospital resuscitation method was key exposure (SALS, BLS). The primary outcome was survival to discharge. RESULTS: A total of 616 consecutive out-of-hospital cardiopulmonary resuscitation cases in NHs were recorded, and 199 (32.3%) underwent SALS. Among the NH arrest patients, the survival discharge rate was a little higher in the SALS group than the BLS group (4.0% vs 1.7%), but the difference was not significant (P = 0.078). Survival discharge with good neurologic outcome rates was 0.5% in the SALS group and 1.0% in the BLS group (P = 0.119). On the other hand, in the non-NH group, all outcome measures significantly improved when SALS was performed compared to BLS alone (survival discharge rate: 10.0% vs 7.3%, P = 0.001; good neurologic outcome: 6.8% vs 3.3%, P < 0.001). CONCLUSIONS: As a result of providing prehospital ACLS with direct medical intervention through remote video calls to paramedics, the survival to discharge rate and that with good neurologic outcome (CPC 1, 2) of non-NH patients significantly improved, however those of NH patients were not significantly increased.

Effects of climate change-related heat stress on labor productivity in South Korea.

This study assessed the potential impact of heat stress on labor productivity in South Korea; as such, stress is expected to increase due to climate change. To quantify the future loss of labor productivity, we used the relationship between the wet-bulb globe temperature and work-rest cycles with representative concentration pathways (RCPs) 4.5 and 8.5 as the climate change scenarios. If only climate factors are considered, then future labor productivity is expected to decline in most regions from the middle of the twenty-first century onwards (2041-2070). From the late twenty-first century onwards, the productivity of heavy outdoor work could decline by 26.1% from current levels under the RCP 8.5 climate scenario. Further analysis showed that regional differences in labor characteristics and the working population had noteworthy impacts on future labor productivity losses. The heat stress caused by climate change thus has a potentially substantial negative impact on outdoor labor productivity in South Korea.

Interleukin-6 induces the lineage commitment of bone marrow-derived mesenchymal multipotent cells through down-regulation of Sox2 by osteogenic transcription factors.

Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are a heterogeneous population of cells that differ in size and morphology. BM-MSCs become committed to the osteogenic lineage as senescence approaches and lose multipotency. Nevertheless, little is known about the effects of cell-cell interaction between different populations on stemness loss and lineage commitment. The current study aimed to identify mechanisms by which cell-cell interactions between heterogeneous BM-MSCs affect stemness and lineage commitment of multipotent subpopulation. The lineage commitment of primitive multipotent cells was strongly induced in the presence of cytokines secreted by senescent-like cells in a cell culture insert system. Senescent-like cells secreted higher levels of interleukin-6 (IL-6) than primitive multipotent cells in a human cytokine array. IL-6 induced the lineage commitment and stemness loss in multipotent cells by decreasing Sox2 expression. Furthermore, we confirmed that IL-6 decreased the transcriptional activity of Sox2 through up-regulation of Runx2 and Dlx5. We suggest a mechanism by which IL-6 modulates the expression of Sox2, resulting in decreased multipotency and causing primitive multipotent cells to undergo osteogenic lineage commitment. This is the first study to identify mechanisms in which the cell-cell interactions between the different populations play important roles in the stemness loss and lineage commitment of multipotent populations.-Yoon, D. S., Kim, Y. H., Lee, S., Lee, K.-M., Park, K. H., Jang, Y., Lee, J. W. Interleukin-6 induces the lineage commitment of bone marrow-derived mesenchymal multipotent cells through down-regulation of Sox2 by osteogenic transcription factors.

Stabilizing chromophore binding on TiO2 for long-term stability of dye-sensitized solar cells using multicomponent atomic layer deposition.

Ambient humidity and high temperature are known to degrade dye-sensitized solar cells (DSSCs) via chromophore desorption. Recently, enhanced dye-attachment to TiO2 surfaces has been realized by coating molecularly functionalized surfaces with inorganic atomic layer deposition (ALD) coatings. Here, we apply this ALD approach to DSSCs and demonstrate that high energy conversion efficiencies can be maintained while significantly extending device lifetimes. While single component ALD layers show improved high-temperature stability, it significantly degraded up to 45% of initial DSSC performance right after ALD. We, however, find that mixed component ALD layers provide initial efficiencies within 90% of their untreated counterparts while still extending device lifetimes. Optimized ALD protection schemes maintain 80% of their initial efficiency after 500 h of thermal aging at 80 °C whereas efficiency of DSSCs with no ALD protection drop below 60% of their initial efficiencies. IR spectroscopy conducted in situ during ALD reveals that carboxylate linker groups transition from unbound or weakly-bound states, respectively, to more strongly bound bidentate structures. This strategy to improve dye-attachment by ALD while maintaining high performance is novel and promising for extending the functional lifetime for DSSCs and other related devices.

Age-Related Decrease in Pellino-1 Expression Contributes to Osteoclast-Mediated Bone Loss.

Aging-related bone loss is driven by various biological factors, such as imbalanced bone metabolism from decreased osteoblast and increased osteoclast activities. Various transcriptional and post-transcriptional factors increase osteoclast activity with aging; however, studies regarding the post-translational regulators of osteoclast activity are still limited. The ubiquitin E3 ligase Pellino-1 is a well-known post-translational regulator of inflammation. However, how Pellino-1 expression regulation affects osteoclast differentiation remains unclear. This study determined that Pellino-1 levels are reduced in bone marrow monocytes (BMMs) from 40-week-old mice compared to 4-week-old mice. Interestingly, conditional Knockout (cKO) of Pellino-1 in 6-week-old mice resulted in decreased bone mass, reduced body size, and lower weight than in Pellino-1 floxed mice; however, these differences are not observed in 20-week-old mice. The increased number of tartrate-resistant acid phosphatase (TRAP)-positive cells and serum levels of C-terminal telopeptides of type I collagen, a marker of bone resorption, in 6-week-old Pellino-1 cKO mice implied a connection between Pellino-1 and the osteoclast population. Enhanced TRAP activity and upregulation of osteoclast genes in BMMs from the cKO mice indicate that Pellino-1 deletion affects osteoclast differentiation, leading to decreased bone mass and heightened osteoclast activity. Thus, targeting Pellino-1 could be a potential gene therapy for managing and preventing osteoporosis.

The new combination of oxygen saturation with age shock index predicts the outcome of COVID-19 pneumonia.

Introduction: Emergency departments around the world have been struggling to deal with patients with COVID-19 and presumed COVID-19. Triaging patients who need further medical support is the key matter to emergency physicians as the delay of proper treatment may worsen the results. The aim of this study was to validate the ability of age shock index and hypoxia-age-shock index at the time of presentation to the emergency department to predict case fatality in patients with COVID-19 pneumonia. Methods: We only included patients who had COVID-19-associated pneumonia who needed in-hospital treatment. The vital signs and oxygen saturation used in the study were collected, especially from the triage sector, before patients were given supplemental oxygen. Results: A total of 241 patients enrolled in the study. The case fatality rate was 27%. The median age of the study samples was 78 (66-86) years with 133 male and 108 female patients. Hypoxia-age-shock index showed the best performance in analysis (odds ratio 15.1, 95% confidence interval: 5.1-44.4; adjusted odds ratio 8.6, 95% confidence interval: 2.8-26.8). Conclusion: The hypoxia-age-shock index was a strong predictor for in-hospital mortality of COVID-19 pneumonia. Furthermore, when it was compared with age shock index, hypoxia-age-shock index showed better performance in predicting fatality of the disease.

Systemic Venous Air Emboli After Emergent Hyperbaric Therapy for Carbon Monoxide Poisoning.

BACKGROUND A venous air embolism is a rare condition but could have a disastrous effect on vital organs. It usually occurs due to iatrogenic sources, such as central venous catheter insertion, neurosurgery, and other invasive procedures. In most cases, hyperbaric oxygen therapy (HBOT) is the best treatment for those conditions. However, multiple venous air emboli after hyperbaric oxygen therapy has not been reported in the literature. CASE REPORT An 82-yr-old woman came to the Emergency Department after inhalation of fumes at the scene of a house fire. She had dizziness and nausea. Her vital signs were normal at the time of presentation. She received HBOT for carbon monoxide poisoning. Soon after the HBOT, the patient started to have dizziness, abdominal pain, and leg pains. Computed tomography scans showed multiple systemic venous air emboli throughout the portal venous system and femoral veins. The air emboli totally disappeared after HBOT with a longer ascent time. CONCLUSIONS To the best of our knowledge, this is the first case of multiple systemic venous air bubbles after emergent HBOT. Physicians should be aware of any kind of complications when treating patients who need HBOT in the emergent setting. Although decompression sickness following HBOT is extremely rare, it should not be ignored by emergency physicians.

Inhibiting the cytosolic function of CXXC5 accelerates diabetic wound healing by enhancing angiogenesis and skin repair.

Diabetic wound healing, including diabetic foot ulcer (DFU), is a serious complication of diabetes. Considering the complexity of DFU development, the identification of a factor that mediates multiple pathogeneses is important for treatment. In this study, we found that CXXC-type zinc finger protein 5 (CXXC5), a negative regulator of the Wnt/ß-catenin pathway, was overexpressed with suppression of the Wnt/ß-catenin pathway and its target genes involved in wound healing and angiogenesis in the wound tissues of DFU patients and diabetes-induced model mice. KY19334, a small molecule that activates the Wnt/ß-catenin pathway by inhibiting the CXXC5-Dvl interaction, accelerated wound healing in diabetic mice. The enhancement of diabetic wound healing could be achieved by restoring the suppressed Wnt/ß-catenin signaling and subsequently inducing its target genes. Moreover, KY19334 induced angiogenesis in hindlimb ischemia model mice. Overall, these findings revealed that restorative activation of Wnt/ß-catenin signaling by inhibiting the function of cytosolic CXXC5 could be a therapeutic approach for treating DFUs.

RUNX2 stabilization by long non-coding RNAs contributes to hypertrophic changes in human chondrocytes.

Background: Chondrocyte hypertrophy has been implicated in endochondral ossification and osteoarthritis (OA). In OA, hypertrophic chondrocytes contribute to the destruction and focal calcification of the joint cartilage. Although studies in this field have remarkably developed the modulation of joint inflammation using gene therapy and regeneration of damaged articular cartilage using cell therapy, studies that can modulate or prevent hypertrophic changes in articular chondrocytes are still lacking. Methods: In vitro hypertrophic differentiation and inflammation assays were conducted using human normal chondrocyte cell lines, TC28a2 cells. Human cartilage tissues and primary articular chondrocytes were obtained from OA patients undergoing total knee arthroplasty. Long non-coding RNAs (lncRNAs), LINC02035 and LOC100130207, were selected through RNA-sequencing analysis using RNAs extracted from TC28a2 cells cultured in hypertrophic medium. The regulatory mechanism was evaluated using western blotting, real-time quantitative polymerase chain reaction, osteocalcin reporter assay, RNA-immunoprecipitation (RNA-IP), RNA-in situ hybridization, and IP. Results: LncRNAs are crucial regulators of various biological processes. In this study, we identified two important lncRNAs, LINC02035 and LOC100130207, which play important roles in hypertrophic changes in normal chondrocytes, through RNA sequencing. Interestingly, the expression level of RUNX2, a master regulator of chondrocyte hypertrophy, was regulated at the post-translational level during hypertrophic differentiation of the normal human chondrocyte cell line, TC28a2. RNA-immunoprecipitation proved the potential interaction between RUNX2 protein and both lncRNAs. Knockdown (KD) of LINC02035 or LOC100130207 promoted ubiquitin-mediated proteasomal degradation of RUNX2 and prevented hypertrophic differentiation of normal chondrocyte cell lines, whereas overexpression of both lncRNAs stabilized RUNX2 protein and generated hypertrophic changes. Furthermore, the KD of the two lncRNAs mitigated the destruction of important cartilage matrix proteins, COL2A1 and ACAN, by hypertrophic differentiation or inflammatory conditions. We also confirmed that the phenotypic changes raised by the two lncRNAs could be rescued by modulating RUNX2 expression. In addition, the KD of these two lncRNAs suppressed hypertrophic changes during chondrogenic differentiation of mesenchymal stem cells. Conclusion: Therefore, this study suggests that LINC02035 and LOC100130207 contribute to hypertrophic changes in normal chondrocytes by regulating RUNX2, suggesting that these two novel lncRNAs could be potential therapeutic targets for delaying or preventing OA development, especially for preventing chondrocyte hypertrophy.

Overgrowth of long bone in rabbits by growth stimulation through metaphyseal hole creation.

Overgrowth of long bones was noted in pediatric patients who underwent anterior cruciate ligament reconstruction. Hyperaemia during creating a metaphyseal hole and the microinstability made by the drill hole may induce overgrowth. This study aimed to determine whether metaphyseal hole creation accelerates growth and increases bone length and compare the effects of growth stimulation between metaphyseal hole creation and periosteal resection. We selected 7- to 8-week-old male New Zealand white rabbits. Periosteal resection (N = 7) and metaphyseal hole creation (N = 7) were performed on the tibiae of skeletally immature rabbits. Seven additional sham controls were included as age-matched controls. In the metaphyseal hole group, the hole was made using a Steinman pin at the same level of periosteal resection, and the cancellous bone beneath the physis was removed by curettage. The vacant space in the metaphysis below the physis was filled with bone wax. Tibiae were collected 6 weeks after surgery. The operated tibia was longer in the metaphyseal hole group (10.43 ± 0.29 cm vs. 10.65 ± 0.35 cm, P = 0.002). Overgrowth was higher in the metaphyseal hole group (3.17 ± 1.16 mm) than in the sham group (- 0.17 ± 0.39 mm, P < 0.001). The overgrowth in the metaphyseal hole group was comparable to that in the periosteal resection group (2.23 ± 1.52 mm, P = 0.287). In rabbits, metaphyseal hole creation and interposition with bone wax can stimulate long bone overgrowth, and the amount of overgrowth is similar to that seen in periosteal resection.

Promoting angiogenesis and diabetic wound healing through delivery of protein transduction domain-BMP2 formulated nanoparticles with hydrogel.

Decreased angiogenesis contributes to delayed wound healing in diabetic patients. Recombinant human bone morphogenetic protein-2 (rhBMP2) has also been demonstrated to promote angiogenesis. However, the short half-lives of soluble growth factors, including rhBMP2, limit their use in wound-healing applications. To address this limitation, we propose a novel delivery model using a protein transduction domain (PTD) formulated in a lipid nanoparticle (LNP). We aimed to determine whether a gelatin hydrogel dressing loaded with LNP-formulated PTD-BMP2 (LNP-PTD-BMP2) could enhance the angiogenic function of BMP2 and improve diabetic wound healing. In vitro, compared to the control and rhBMP2, LNP-PTD-BMP2 induced greater tube formation in human umbilical vein endothelial cells and increased the cell recruitment capacity of HaCaT cells. We inflicted large, full-thickness back skin wounds on streptozotocin-induced diabetic mice and applied gelatin hydrogel (GH) cross-linked by microbial transglutaminase containing rhBMP2, LNP-PTD-BMP2, or a control to these wounds. Wounds treated with LNP-PTD-BMP2-loaded GH exhibited enhanced wound closure, increased re-epithelialization rates, and higher collagen deposition than those with other treatments. Moreover, LNP-PTD-BMP2-loaded GH treatment resulted in more CD31- and α-SMA-positive cells, indicating greater neovascularization capacity than rhBMP2-loaded GH or GH treatments alone. Furthermore, in vivo near-infrared fluorescence revealed that LNP-PTD-BMP2 has a longer half-life than rhBMP2 and that BMP2 localizes around wounds. In conclusion, LNP-PTD-BMP2-loaded GH is a viable treatment option for diabetic wounds.

Osteochondral Repair with Autologous Cartilage Transplantation with or without Bone Grafting: A Short Pilot Study in Mini-Pigs.

OBJECTIVE: Treatment strategies for osteochondral defects, for which particulated autologous cartilage transplantation (PACT) is an emerging treatment strategy, aim to restore the structure and function of the hyaline cartilage. Herein, we compared the efficacy of PACT with control or human transforming growth factor-ß (rhTGF-ß), and clarified the necessity of bone graft (BG) with PACT to treat shallow osteochondral defects in a porcine model. DESIGN: Two skeletally mature male micropigs received 4 osteochondral defects in each knee. The 16 defects were randomized to (1) empty control, (2) PACT, (3) PACT with BG, or (4) rhTGF-ß. Animals were euthanized after 2 months and histomorphometry, immunofluorescence analysis, semiquantitative evaluation (O'Driscoll score), and magnetic resonance observation of cartilage repair tissue (MOCART) score were performed. RESULTS: Hyaline cartilages, glycosaminoglycan synthesis, and collagen type II staining were more abundant in the PACT than in the control and rhTGF-ß groups. The O'Driscoll score was significantly different between groups (P < 0.001), with both PACT groups showing superiority (P = 0.002). PACT had the highest score (P = 0.002), with improved restoration of subchondral bone compared with PACT with BG. The MOCART score showed significant differences between groups (P = 0.021); MOCART and O'Driscoll scores showed high correlation (r = 0.847, P < 0.001). CONCLUSION: Treatment of osteochondral defects with PACT improved tissue quality compared with that with control or rhTGF-ß in a porcine model. BG, in addition to PACT, may be unnecessary for shallow osteochondral defects. Clinical Relevance. BG may not be necessary while performing PACT.

Characterization of a recombinant aryl ß-glucosidase from Neosartorya fischeri NRRL181.

An isolated gene from Neosartorya fischeri NRRL181 encoding a ß-glucosidase (BGL) was cloned, and its nucleotide sequence was determined. DNA sequence analysis revealed an open reading frame of 1,467 bp, capable of encoding a polypeptide of 488 amino acid residues. The gene was over-expressed in Escherichia coli, and the protein was purified using nickel-nitrilotriacetic acid chromatography. The purified recombinant BGL showed a high level of catalytic activity, with V (max) of 886 µmol min(-1) mg-protein(-1) and a K (m) of 68 mM for p-nitrophenyl-ß-D: -glucopyranoside (pNPG). The optimal temperature for enzyme activity was about 40°C, and the optimal pH was about 6.0. A homology model of N. fischeri BGL1 was constructed based on the X-ray crystal structure of Phanerochaete chrysosporium BGLA. Molecular dynamics simulation studies of the enzyme with the pNPG and cellobiose shed light on the unique substrate specificity of N. fischeri BGL1 only towards pNPG.

Drug repositioning of polaprezinc for bone fracture healing.

Fractures and related complications are a common challenge in the field of skeletal tissue engineering. Vitamin D and calcium are the only broadly available medications for fracture healing, while zinc has been recognized as a nutritional supplement for healthy bones. Here, we aimed to use polaprezinc, an anti-ulcer drug and a chelate form of zinc and L-carnosine, as a supplement for fracture healing. Polaprezinc induced upregulation of osteogenesis-related genes and enhanced the osteogenic potential of human bone marrow-derived mesenchymal stem cells and osteoclast differentiation potential of mouse bone marrow-derived monocytes. In mouse experimental models with bone fractures, oral administration of polaprezinc accelerated fracture healing and maintained a high number of both osteoblasts and osteoclasts in the fracture areas. Collectively, polaprezinc promotes the fracture healing process efficiently by enhancing the activity of both osteoblasts and osteoclasts. Therefore, we suggest that drug repositioning of polaprezinc would be helpful for patients with fractures.

TLR4 downregulation by the RNA-binding protein PUM1 alleviates cellular aging and osteoarthritis.

Dysfunction of mRNA or RNA-binding proteins (RBPs) causes cellular aging and age-related degenerative diseases; however, information regarding the mechanism through which RBP-mediated posttranscriptional regulation affects cellular aging and related disease processes is limited. In this study, PUM1 was found to be associated with the self-renewal capacity and aging process of human mesenchymal stem cells (MSC). PUM1 interacted with the 3'-untranslated region of Toll-like receptor 4 (TLR4) to suppress TLR4 mRNA translation and regulate the activity of nuclear factor-κB (NF-κB), a master regulator of the aging process in MSCs. PUM1 overexpression protected MSCs against H2O2-induced cellular senescence by suppressing TLR4-mediated NF-κB activity. TLR4-mediated NF-κB activation is a key regulator in osteoarthritis (OA) pathogenesis. PUM1 overexpression enhanced the chondrogenic potential of MSCs even under the influence of inflammation-inducing factors, such as lipopolysaccharide (LPS) or interleukin-1ß (IL-1ß), whereas the chondrogenic potential was reduced following the PUM1 knockdown-mediated TLR4 activation. PUM1 levels decreased under inflammatory conditions in vitro and during OA progression in human and mouse disease models. PUM1 knockdown in human chondrocytes promoted chondrogenic phenotype loss, whereas PUM1 overexpression protected the cells from inflammation-mediated disruption of the chondrogenic phenotype. Gene therapy using a lentiviral vector encoding mouse PUM1 showed promise in preserving articular cartilage integrity in OA mouse models. In conclusion, PUM1 is a novel suppressor of MSC aging, and the PUM1-TLR4 regulatory axis represents a potential therapeutic target for OA.

Application of the Team Emergency Assessment Measure for Prehospital Cardiopulmonary Resuscitation.

INTRODUCTION: Communication and teamwork are critical for ensuring patient safety, particularly during prehospital cardiopulmonary resuscitation (CPR). The Team Emergency Assessment Measure (TEAM) is a tool applicable to such situations. This study aimed to validate the TEAM efficiency as a suitable tool even in prehospital CPR. METHODS: A multi-centric observational study was conducted using the data of all non-traumatic out-of-hospital cardiac arrest patients aged over 18 years who were treated using video communication-based medical direction in 2018. From the extracted data of 1494 eligible patients, 67 sample cases were randomly selected. Two experienced raters were assigned to each case. Each rater reviewed 13 or 14 videos and scored the TEAM items for each field cardiopulmonary resuscitation performance. The internal consistency, concurrent validity, and inter-rater reliability were measured. RESULTS: The TEAM showed high reliability with a Cronbach's alpha value of 0.939, with a mean interitem correlation of 0.584. The mean item-total correlation was 0.789, indicating significant associations. The mean correlation coefficient between each item and the global score range was 0.682, indicating good concurrent validity. The mean intra-class correlation coefficient was 0.804, indicating excellent agreement. DISCUSSION: The TEAM can be a valid and reliable tool to evaluate the non-technical skills of a team of paramedics performing CPR.