Chemo-, regio- and stereoselective access to polysubstituted 1,3-dienes via Nickel-catalyzed four-component reactions.

1,2-Difunctionalization of alkynes offers a straightforward approach to access polysubstituted alkenes. However, simultaneous multi-component cascade transformations including difunctionalization of two alkynes with both syn- and anti-selectivity in one catalyst system is undeveloped and proves to be a significant challenge. Herein, we report a Nickel-catalyzed four-component reaction to access polysubstituted 1,3-dienes using two terminal alkynes, aryl boroxines, and perfluoroalkyl iodides, wherein the reaction forms three new C-C bonds in a single vessel and serve as a modular strategy to access polysubstituted 1,3-dienes with excellent chemoselectivity, good regioselectivity and exclusive stereoselectivity. Control experiments reveal the plausible reaction mechanism and DFT calculations explain the cause for the formation of this unusual four-component reaction. Furthermore, we successfully incorporate two biologically active units into 1,2,3,4-tetrasubstituted 1,3-dienes, which greatly increases the diversity of molecular scaffolds and brings more potential values to medicinal chemistry, the synthetic utility of our protocol is further demonstrated by the late-stage transformations.

Manganese-enriched prussian blue nanohybrids with smaller electrode potential and lower charge transfer resistance to enhance combination therapy.

Prussian blue (PB) is authenticated in clinical treatment, while it generally exhibits unfavorable chemodynamic therapy (CDT) performance. Herein, we developed manganese-doped prussian blue (PBM) nanoparticles to significantly enhance both CDT and photothermal therapy (PTT) effect. The lower redox potential of Mn3+/2+ (0.088 V) in PBM against that of Fe2+/3+ (0.192 V) in PB leads to favorable electron transfer of PBM with respect to PB. Besides, PBM has a lower charge-transfer resistance (Rct) of 2.98 Ω than 4.83 Ω of PB. Once PBM entering the tumor microenvironment (TME), Mn3+ may be readily reduced by glutathione (GSH) and therein to enhance intracellular oxidative stress. Meanwhile, the superoxide dismutase (SOD)-like activity of PBM facilitates the conversion of endogenous superoxide (O2•-) into H2O2. Mn2+ subsequently catalyzes H2O2 to generate toxic hydroxyl radicals (•OH). Notably, the PBM plus laser irradiation can effectively trigger a robust immunogenic cell death (ICD) due to the combination therapy of CDT and PTT. Additionally, the mice treated by PBM followed by laser irradiation efficiently avoided splenomegaly and lung metastasis, along with significant up-regulation of the Stimulator of Interferon Genes (STING) expression. Overall, PBM significantly inhibits tumor growth and metastasis, making it a promising multifunctional nanoplatform for cancer treatment.

SARS-CoV-2 Accessory Protein Orf7b Induces Lung Injury via c-Myc Mediated Apoptosis and Ferroptosis.

The pandemic of coronavirus disease 2019 (COVID-19) has been the foremost modern global public health challenge. The airway is the primary target in severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) infection, with substantial cell death and lung injury being signature hallmarks of exposure. The viral factors that contribute to cell death and lung injury remain incompletely understood. Thus, this study investigated the role of open reading frame 7b (Orf7b), an accessory protein of the virus, in causing lung injury. In screening viral proteins, we identified Orf7b as one of the major viral factors that mediates lung epithelial cell death. Overexpression of Orf7b leads to apoptosis and ferroptosis in lung epithelial cells, and inhibitors of apoptosis and ferroptosis ablate Orf7b-induced cell death. Orf7b upregulates the transcription regulator, c-Myc, which is integral in the activation of lung cell death pathways. Depletion of c-Myc alleviates both apoptotic and ferroptotic cell deaths and lung injury in mouse models. Our study suggests a major role of Orf7b in the cell death and lung injury attributable to COVID-19 exposure, supporting it as a potential therapeutic target.

Risk factors for hypoxaemia following hip fracture surgery in elderly patients who recovered from COVID-19: a multicentre retrospective study.

Objectives: To explore the risk factors associated with postoperative hypoxaemia in elderly patients who have recovered from coronavirus disease (COVID-19) and underwent hip fracture surgery in the short term. Design: Multicentre retrospective study. Setting: The study was performed in three first 3A-grade hospitals in China. Participants: A sequential sampling method was applied to select study participants. Medical records of 392 patients aged ≥65 years who had recovered from COVID-19 and underwent hip fracture surgery at three hospitals in China between 1 November, 2022, and 15 February, 2023, were reviewed. Interventions: Patients were assigned to hypoxaemia or non-hypoxaemia groups, according to whether hypoxaemia occurred after surgery. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for postoperative hypoxaemia. Results: The incidence of postoperative hypoxaemia was 38.01%. Statistically significant differences were found between the two groups in terms of age, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, presence of expectoration symptoms, preoperative hypoxaemia, chronic obstructive pulmonary disease, pulmonary inflammation, time between recovery from COVID-19 and surgery, anaesthetic mode, surgical procedure, intraoperative blood loss, intraoperative infusion, duration of surgery, and length of hospital stay (p < 0.05). Furthermore, patients with BMI ≥28.0 kg/m2, expectoration symptoms, presence of preoperative hypoxaemia, ASA classification III, time between recovery from COVID-19 and surgery ≤2 weeks, and general anaesthesia were potential risk factors for postoperative hypoxaemia. Conclusion: Obesity, expectoration symptoms, preoperative hypoxaemia, ASA classification III, time between recovery from COVID-19 and surgery ≤2 weeks, and general anaesthesia were potential risk factors for postoperative hypoxaemia in elderly patients who recovered from COVID-19 and underwent hip fracture surgery in the short term.

Incidence and Risk Factors of Admission Deep Vein Thrombosis in Patients With Traumatic Fracture: A Multicenter Retrospective Study.

To identify risk factors of admission deep vein thrombosis (DVT) in patients with traumatic fractures. Medical records of 1596 patients with traumatic fractures were reviewed. According to the ultrasound reports of the lower extremity veins, patients were assigned to the DVT or non-DVT group. Univariate and multivariate logistic regression analyses were used to identify the independent risk factors of DVT, and the receiver operating characteristic (ROC) curve was used to analyze the predictive value of the D-dimer level for DVT. DVT admission incidence was 20.67%. Statistically significant differences were revealed between the 2 groups in terms of age, sex, fracture site, presence of hypertension, coronary heart disease, stroke, smoking status, time from injury to admission, and levels of fasting blood glucose, hemoglobin, fibrinogen, D-dimer, and hematocrit. Multivariate analysis results showed that age above 50 years, female, above-knee fracture, cigarette smoking, injury-to-admission delay beyond 48 h, low hemoglobin levels, high fasting blood glucose levels, and high D-dimer levels were independent risk factors for admission DVT. ROC analysis showed that the D-dimer level was effective for the prediction of admission DVT in patients with peri-knee and below-knee fractures (area under the curve [AUC] = 0.7296, cutoff point = 1.21 mg/L). An age over 50 years, female, above-knee fracture, smoking, injury-to-admission delay beyond 48 h, decreased hemoglobin level, and increased fasting blood glucose and D-dimer levels were found to be potential independent risk factors for admission DVT. In patients with peri-knee and below-knee fractures, the plasma D-dimer level was effective in predicting admission DVT.

N-acetyl Cysteine Inhibits Cell Proliferation and Differentiation of LPSInduced MC3T3-E1 Cells Via Regulating Inflammatory Cytokines.

BACKGROUND: Peri-implantitis is one of the most common complications in oral implantation and could lead to the loss of the function of bone tissues around implants. METHODS: This study used lipopolysaccharide (LPS) as a stimulant for MC3T3-E1 cells and N-acetyl cysteine (NAC) as an inhibitor to inhibit the effect of LPS to investigate the effect of NAC on the expression of bone formation related factors and inflammatory-related factors of osteoblasts under the action of LPS. RESULTS: In this study, we found that the cell proliferation and cell differentiation were significantly promoted when NAC concentrations were between 0 ~ 0.5 mM, but were inhibited when the concentration exceeded 0.5 mM. LPS had a slightly promoting effect on the cell proliferation before 20 µg/mL but inhibited the cell proliferation after 20 µg/mL. LPS reduced protein and gene expressions of Runx2, ALP and BGP and increased protein and gene expressions of NF-κB and TNF-α. NAC reversibly regulated the LPS's regulation on the expression of MC3T3-E1 cell cytokine gene and protein. CONCLUSION: The optimal NAC concentration for treating MC3T3-E1 cells is 0.5 mM, and the optimal LPS concentration for stimulating MC3T3-E1 cells is 20 µg/mL. NAC plays an active role in regulating the differentiation of MC3T3-E1 cells, and can inhibit LPS to regulate the differentiation of MC3T3-E1 cells. NAC promotes the expression of an osteogenic factor of MC3T3-E1cells and inhibits the expression of inflammatory cytokines.

Cone-beam X-ray luminescence computed tomography based on MLEM with adaptive FISTA initial image.

BACKGROUND AND OBJECTIVE: As an emerging dual-mode optical molecular imaging, cone-beam X-ray luminescence computed tomography (CB-XLCT) has shown potential in early tumor diagnosis and other applications with increased depth and little autofluorescence. However, due to the low transfer efficiency of PNPs to convert X-ray energy to visible or near-infrared (NIR) light and X-ray dose limitation, the signal to noise ratio of projections is quite low, making the quality of CB-XLCT relatively poor. METHODS: To improve the reconstruction quality of low-counts CB-XLCT imaging, an adaptive reconstruction algorithm (named ADFISTA-MLEM) based on the maximum likelihood expectation estimation (MLEM) framework is proposed for CB-XLCT reconstruction from Poisson distributed projections. In the proposed framework, the image reconstructed by fast iterative shrinkage-thresholding algorithm (FISTA) is used as the initial image for MLEM iterations to improve reconstruction accuracy, in which both the projection noise model and the sparsity constraint of the image could be considered. For relative quantitative imaging, a specific normalization is applied to the projection data and system matrix. To determine the hyperparameter of FISTA, which may be different for different projections, an adaptive strategy (ADFISTA) is then designed for adaptive update of the hyperparameter with reconstructed image in each iteration. RESULTS AND CONCLUSIONS: Results from numerical simulations and phantom experiments indicate that the proposed framework can obtain superior reconstruction accuracy in terms of contrast to noise ratio and shape similarity. In addition, high intensity-concentration linearity between different probe targets indicates its potential for quantitative CB-XLCT imaging.

Stability of SARS-CoV-2-Encoded Proteins and Their Antibody Levels Correlate with Interleukin 6 in COVID-19 Patients.

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has become a severe global public health crisis. Therefore, understanding the molecular details of SARS-CoV-2 will be critical for fighting the virus's spread and preventing future pandemics. In this study, we globally profiled the stability of SARS-CoV-2-encoded proteins, studied their degradation pathways, and determined their correlation with the antibody responses in patient plasma. We identified 18 proteins with unstable half-lives and 6 relatively stable proteins with longer half-lives. The labile SARS-CoV-2 proteins were degraded mainly by the ubiquitin-proteasome pathway. We also observed a significant correlation between antibody levels and protein half-lives, which indicated that a stable antigen of SARS-CoV-2 could be more effective for eliciting antibody responses. In addition, levels of antiviral antibodies targeting NSP10 were found to be negatively correlated with systemic levels of interleukin 6 (IL-6) in patients. These findings may facilitate the development of novel therapeutic or diagnostic approaches. IMPORTANCE SARS-CoV-2, the etiological cause of COVID-19, carries 29 genes in its genome. However, our knowledge of the viral proteins in biological and biochemical aspects is limited. In this study, we globally profiled the stability of the viral proteins in living lung epithelial cells. Importantly, the labile SARS-CoV-2-encoded proteins were mainly degraded through the ubiquitin-proteasome pathway. Stable proteins, including spike and nucleocapsid, of SARS-CoV-2 were more effective in eliciting antibody production. The levels of antiviral antibodies targeting NSP10 were negatively correlated with systemic levels of IL-6 in COVID-19 patients.

[Effect of Taohong Siwu Decoction() early intervention on mesenchymal stem cells homing in fracture healing in rats].

OBJECTIVE: To observe the effects of Taohong Siwu Decoction(, THSWD) on the mesenchymal stem cells(MSCs) migration, homing number and cytokine expression in callus during the early process of fracture healing, and to explore the mechanism of THSWD on accelerationg fracture healing by regulating the homing of MSCs in rats. METHODS: A rat model of right femoral shaft open fracture was established. Thirty-two 5-week-old male Sprague-Dawley rats, weighting 110 to 130 g, were divided into control group, low-dose group, medium-dose group and high-dose group by using random number table. Distilled water was given to the control group, and the other groups were given Taohong Siwu Decoction. The rats were gavaged twice a day for 5 consecutive days after surgery. Bone volume/tissue volume(BV/TV) and bone mineral density(BMD) were observed using micro-computed tomography (micro-CT) at 21 days after surgery. At 5 days post-fracture, peripheral blood MSCs from THSWD treated and untreated rats were cultured in vitro. Subsequently, the migration ability of MSCs was observed by cell migration assay. The number of MSCs homing to the callus at the early stage of fracture (5 d) was detected by Immunohistochemistry (IHC). Protein chip was used to detect the expression of cytokines in callus. RESULTS: Micro-CT results showed that BV/TV was higher in the high-dose group than in the medium-dose group (P=0.032), and higher in the medium-dose group than in the low-dose group(P=0.041), with no difference between the control and low-dose group (P=0.651). In addition, there was no difference in BMD between low-dose group and the model group (P=0.671), and lower in the low-dose group than in the medium-dose group(P=0.018), and the medium-dose group was lower than the high-dose group(P=0.008). Cell migration assay showed that THSWD promotes enhanced the migration ability of peripheral blood MSCs. IHC assay revealed that CD45-, CD90+, CD29+ MSCs significantly increased in bone callus after THSWD intervention compared with the control group. Protein chip showed that THSWD promoted the upregulation of CINC-1(×2.91), CINC-3(×1.59), LIX(×1.5), Thymus Chemokine (×2.55), VEGF (×1.22) and the down-regulation of TIMP-1 (×2.98). CONCLUSION: THSWD, a representative formula of "promoting blood circulation and removing blood stasis", can significantly accelerate fracture healing, and its mechanism may be related to enhancing the migration ability of peripheral blood MSCs and up-regulating CINC-1, CINC-3, LIX, Thymus Chemokine, VEGF and down-regulating TIMP-1 in bone callus, which promotes the peripheral blood MSCs homing in the early stage of fracture.

Taohong Siwu decoction promotes the process of fracture healing by activating the VEGF-FAK signal pathway and systemically regulating the gut microbiota.

AIMS: This study aimed to explore the effect of Taohong Siwu Decoction (THSWD) on bone marrow mesenchymal stem cells (BMSCs) at the cellular level and the possible mechanism of systemic regulation of gut microbiota on fracture recovery. METHODS AND RESULTS: Cell Counting Kit-8 (CCK-8) experiments show that THSWD effectively promotes the proliferation of BMSCs. Transwell and wound healing assays show that THSWD effectively promotes the invasion and migration of BMSCs. Alizarin red staining showed that the THSWD model enhanced the osteogenic differentiation of BMSCs. Moreover, the effect of THSWD on BMSCs is time- and concentration-dependent. RT-qPCR and western blot results showed that THSWD treatment up-regulated the expression of vascular endothelial growth factor (VEGF) and focal adhesion kinase (FAK) at mRNA and protein levels, respectively. Haematoxylin-eosin and crocin O-quick green staining showed that after 14 days of THSWD treatment, the area of callus and cartilage regeneration at the fracture site increased significantly in rats with right femoral shaft fractures. Gut microbiota was changed in fractured rats, such as the abundance of Bacteroidetes and Firmicutes was increased. THSWD showed positive regulation of both to a certain extent. CONCLUSION: THSWD up-regulates VEGF and activates the FAK signalling pathway to enhance the development and differentiation of BMSCs, and systematically regulates the gut microbiota to promote fracture healing. SIGNIFICANCE AND IMPACT OF STUDY: This study provides new insights on the cellular and systemic level to understand the mechanism of THSWD in the treatment of fractures.

Antimicrobial peptide WAM-1: a promising antibacterial and anti-inflammatory drug against carbapenem-resistant Klebsiella pneumoniae.

BACKGROUND: The emergence and spread of carbapenem-resistant Klebsiella pneumoniae (CRKP) pose a threat to public health. Antimicrobial peptides provide a new treatment option for CRKP infections. OBJECTIVES: We studied antibacterial activities of WAM-1 against CRKP in vitro and in vivo and explored its possible mechanism. We verified safety and factors affecting antibacterial effect. Furthermore, anti-inflammatory effects were investigated. METHODS: We selected eight CRKP and eight carbapenem-susceptible K. pneumoniae to explore the antibacterial activity of WAM-1 by broth microdilution (BMD). The possible mechanism was investigated by alkaline phosphatase leakage and propidium iodide (PI). We evaluated safety of WAM-1 by cytotoxicity and haemolysis and effects of temperature and serum on the antibacterial activity. We investigated in vivo efficacy of WAM-1 by the Galleria mellonella infection model. We investigated the effect of WAM-1 on TNF-α. RESULTS: BMD showed that WAM-1 had a good antibacterial effect with MICs of 2-4 mg/L and MBCs of 4-8 mg/L. RT-qPCR showed that WAM-1 could inhibit the expression of TNF-α. The cytotoxicity and haemolysis test proved that WAM-1 had certain potential application in vivo. Alkaline phosphatase leakage and PI fluorescence showed that WAM-1 was highly likely to exert an antibacterial effect by destroying bacterial membrane. The G. mellonella infection model suggested that WAM-1 may have a good therapeutic effect in vivo. Temperature had little effect on the activity of WAM-1. Serum, however, reduced WAM-1 activity. CONCLUSIONS: WAM-1 has good antibacterial effect and potential anti-inflammatory effect on infection caused by CRKP.

Tanshinone IIA Ameliorates Inflammation Response in Osteoarthritis via Inhibition of miR-155/FOXO3 Axis.

BACKGROUND: Osteoarthritis (OA) is the most common joint disorder characterized by degeneration of the articular cartilage and joint destruction with an associated risk of mobility disability in elderly people. Although a lot of achievements have been made, OA is still regarded as an incurable disease. Therefore, the pathological mechanisms and novel therapeutic strategies of OA need more investigation. METHODS: MTT assay was conducted to measure the viability of chondrocytes after LPS treatment. Cell apoptosis was analyzed by annexin V/propidium iodide labeling. ELISA was used to determine the concentrations of interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α in the culture supernatant of chondrocytes. The expression level of miR-155, IL-1ß, FOXO3, TNF-α, IL-6, caspase-3, and caspase-9 in chondrocytes was analyzed by RT-qPCR or Western blot. RESULTS: We found that LPS led to inflammatory responses, cell apoptosis, and increased miR-155 expression in human articular chondrocytes. Tanshinone IIA could inhibit LPS-induced inflammation and cell apoptosis of chondrocytes via regulating the expression of miR-155 and FOXO3. miR-155 directly targeted the 3'-UTR of FOXO3 to regulate its expression. CONCLUSIONS: Taken together, our data suggest tanshinone IIA ameliorates inflammation response in OA via inhibition of the miR-155/FOXO3 axis, and provide some evidences that tanshinone IIA could be designed and developed as a new promising clinical therapeutic drug for OA patients.

[Study on MSCs homing and its research on osteodiseases].

Mesenchymal stem cell (MSCs) has recently emerged as an appealing and potential therapeutic strategy to cure a diverse range of diseases in the orthopaedic field. Owing to its capacity of osteogenic differentiation, most of researches just focused on promoting MSC differentiation. With the in-depth study, MSCs homing is also a key issue for bone formation and bone diseases treatment, which have been described that MSCs mobilize from in situ environment (bone marrow) and migrate into injured tissues during the healing process through peripheral circulation. MSC homing is the incipient step of bone formation. MSCs need to firstly migrate to the bone surface and then differentiate into osteogenic cells to enhance bone repair. Promoting MSCs homing have been shown to improve recovery of several orthopedic diseases, such as osteoporosis, fracture, bone defect and wear-particle-related osteolysis. Therefore, further research on MSCs homing may provide a new thinking for treatment of osteoporosis.

Catharmus tinctorius volatile oil promote the migration of mesenchymal stem cells via ROCK2/Myosin light chain signaling.

MSC transplantation has been explored as a new clinical approach to stem cell-based therapies for bone diseases in regenerative medicine due to their osteogenic capability. However, only a small population of implanted MSC could successfully reach the injured areas. Therefore, enhancing MSC migration could be a beneficial strategy to improve the therapeutic potential of cell transplantation. Catharmus tinctorius volatile oil (CTVO) was found to facilitate MSC migration. Further exploration of the underlying molecular mechanism participating in the pro-migratory ability may provide a novel strategy to improve MSC transplantation efficacy. This study indicated that CTVO promotes MSC migration through enhancing ROCK2 mRNA and protein expressions. MSC migration induced by CTVO was blunted by ROCK2 inhibitor, which also decreased myosin light chain (MLC) phosphorylation. Meanwhile, the siRNA for ROCK2 inhibited the effect of CTVO on MSC migration ability and attenuated MLC phosphorylation, suggesting that CTVO may promote BMSC migration via the ROCK2/MLC signaling. Taken together, this study indicates that C. tinctorius volatile oil could enhance MSC migration via ROCK2/MLC signaling in vitro. C. tinctorius volatile oil-targeted therapy could be a beneficial strategy to improve the therapeutic potential of cell transplantation for bone diseases in regenerative medicine.

N-acetyl cysteine inhibits lipopolysaccharide-mediated induction of interleukin-6 synthesis in MC3T3-E1 cells through the NF-kB signaling pathway.

BACKGROUND: Interleukin-6 (IL-6) is a potent stimulator of osteoclastic activity. Lipopolysaccharide (LPS) has been shown to regulate the expression of potent inflammatory factors, including TNF-α and IL-6. Currently, effective therapeutic treatments for bacteria-caused bone destruction are limited. N-acetyl cysteine (NAC) is an antioxidant small molecule that possibly modulates osteoblastic differentiation. However, whether NAC can affect the LPS-mediated reduction of IL-6 synthesis in MC3T3-E1 cells is still unknown. AIMS: The aim of this study was to investigate the role of NAC in the LPS -mediated reduction of IL-6 synthesis by MC3T3-E1 cells and to explore the underlying molecular mechanisms. In addition, we aimed to determine the involvement of the NF-kB pathway in any changes in IL-6 expression observed in response to LPS and NAC. METHODS: MC3T3-E1 cells (ATCC, CRL-2593) were cultured in α-minimum essential medium. Cells were stimulated using NAC or LPS at various concentrations. Cell proliferation was observed at multiple time points using a cell counting kit 8 (CCK-8). IL-6 mRNA expression and protein synthesis were determined using quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay analyses. NF-kB mRNA expression and protein synthesis was determined using qPCR and Western blots analyses. RESULTS: The results demonstrate that LPS induced IL-6 and NF-kB mRNA expression and protein synthesis in the cultured MC3T3-E1 cells. However, these effects were abolished following pre-treatment with NAC. Pretreatment with NAC (1 mmol/l) or BAY11-7082 (10 µmol/l) both significantly inhibited the NF-kB activity induced by LPS. CONCLUSION: NAC inhibits the LPS-mediated induction of IL-6 synthesis in MC3T3-E1 cells through the NF-kB pathway.

Application of a Novel "Turn-on" Fluorescent Material to the Detection of Aluminum Ion in Blood Serum.

A novel "turn-on" fluorescent bioprobe, 1,2,3,4,5-penta(4-carboxyphenyl)pyrrole sodium salt (PPPNa), with aggregation-enhanced emission characteristics was synthesized for the in situ quantitative detection of Al3+ in serum. It exhibited a high selectivity to Al3+ in both simulated serum and fetal calf serum with no interferences from other metal ions or serum components observed and no isolation required. A weak interaction between PPPNa and serum albumin was found, which caused no interference, but enhanced fluorescence response of PPPNa to Al3+ and improved detection sensitivity. The limit of detection was determined to be 1.50 µmol/L Al3+ in phosphate-buffered saline solution containing 33 µg/mL bovine serum albumin (BSA) and decreased to 0.98 µmol/L as BSA concentration increased to 100 µg/mL. The fluorescence "turn-on" mechanism of the PPPNa probe to detect Al3+ was proposed. A bidentate complex is formed between the carboxy group of PPPNa and Al3+, causing the photoluminescence (PL) emission enhancement by aggregation. BSA chains further strengthen the stacking compactness of the aggregates of PPPNa and Al3+ and consequently enhance the PL emission of PPPNa by further promoting the restriction of intramolecular rotation of the phenyl ring. Its application to the in situ Al3+ was successfully demonstrated with HeLa cells and NIH 3T3 cells. The low cytotoxicity and highly selective response of PPPNa to Al3+ endow its great potentials to in vivo detecting and imaging of Al3+ as well as an absorbent of Al3+.

(+)-Cholesten-3-one induces osteogenic differentiation of bone marrow mesenchymal stem cells by activating vitamin D receptor.

In our previous reports, it was revealed that steroids in traditional Chinese medicine (TCM) have the therapeutic potential to treat bone disease. In the present study, an in vitro model of a vitamin D receptor response element (VDRE) reporter gene assay in mesenchymal stem cells (MSCs) was used to identify steroids that enhanced osteogenic differentiation of MSCs. (+)-cholesten-3-one (CN), which possesses a ketone group that is modified in cholesterol and cholesterol myristate, effectively promoted the activity of the VDRE promoter. Phenotypic cellular analysis indicated that CN induced differentiation of MSCs into osteogenic cells and increased expression of specific osteogenesis markers, including alkaline phosphatase, collagen II and Runt-related transcription factor 2. Furthermore, CN significantly increased the expression of osteopontin, the target of the vitamin D receptor (VDR), which indicated that CN may activate vitamin D receptor signaling. Over-expression of VDR or knockdown studies with VDR-small interfering RNA revealed that the pro-differentiation effects induced by CN required VDR. Furthermore, the present study determined that the C-terminal region of the VDR is responsible for the action of CN. Taken together, the present findings demonstrated that CN induced osteogenic differentiation of MSCs by activating VDR. The present study explored the regulation of stem cells by using a series of similar steroids and provided evidence to support a potential strategy for the screening of novel drugs to treat bone disease in the future.

Protective effect of berberine against oxidative stress-induced apoptosis in rat bone marrow-derived mesenchymal stem cells.

Bone marrow-derived mesenchymal stem cells (BMSCs) have the potential to be used for the treatment of delayed union, nonunion or persistent bone defects in MSC-based cell therapy. However, implantation of BMSCs into the fracture site is confronted with apoptosis on account of harsh conditions and oxidative stress. In the present study, the anti-apoptotic effects of berberine (BBR) on BMSCs subjected to hydrogen peroxide (H2O2) are investigated, and the potential underlying mechanisms are explored. Oxidative injury was induced by exposure to H2O2, and cell viability was assessed using a cell counting kit-8 assay. The apoptosis of BMSCs was measured by Hoechst 33258 and Annexin V-fluorescein isothiocyanate/propidium iodide assay. Reactive oxygen species staining and superoxide dismutase (SOD) assay were applied to assess the anti-oxidative effect of BBR. Finally, western blot was performed to measure the expression levels of phosphorylated (p)-Akt, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and cleaved caspase-3. In the present study, it was identified that BBR remarkably attenuated H2O2-induced apoptotic cell death via quenching ROS production and increasing SOD activity. Further studies indicated that BBR can reduce apoptosis by upregulating the expression level of p-Akt and Bcl-2, and downregulating the expression levels of Bax and cleaved caspase-3. Taken together, the results of the present study demonstrate that pretreatment with BBR could alleviate H2O2-induced apoptosis in rat BMSCs in vitro.

Non-invasive biopsy of doped-ions inside optical substrate by modified two-photon microscopy.

Doped-ion based optical elements play key roles in optical signal processes, including amplification, absorption, wavelength-filtering, lighting, and polarizing plate. Non-invasively mapping the spatial distribution of the ion concentrations in these optical elements is highly desirable either during the fabrication process or to determine their optical qualities. In this work, we applied modified two-photon fluorescence (m-TPF) microscopy to trace the ion-distributions deep inside the optical elements. For demonstration purposes, polyvinyl alcohol (PVA) polymer films inside polarizing plates are taken as an example, where the spatial distributions of Iodine-dyed ions were measured by the m-TPF microscope in a fast and non-invasive way. The durability of the polarizer films can be distinguished from the axial distribution of the Iodine-dyed ions, without the need to perform a biopsy. This proposed method and demonstrated results show great potential for monitoring the spatial distributions of doped-ions in the optical elements quickly and non-destructively, which would be of great benefit in both scientific research and industrial applications.

25-Hydroxyvitamin D concentrations in children with Crohn's disease supplemented with either 2000 or 400 IU daily for 6 months: a randomized controlled study.

OBJECTIVES: To assess vitamin D status of pediatric patients with Crohn's disease (CD) and to compare their serum 25-hydroxyvitamin D (s-25OHD) with established cutoffs and assess whether 6 months of supplementation with 2000 IU/d, vs 400 IU/d, would reduce the group prevalence of vitamin D below these cutoffs. STUDY DESIGN: Subjects 8-18 years (n = 83) with quiescent CD were randomized to either 400 or 2000 IU vitamin D3/d for 6 months. RESULTS: Baseline mean ± SD s-25OHD was 24 ± 8 ng/mL; 13 subjects (16%) had an s-25OHD <16 ng/mL, 27 (33%) < 20 ng/mL, and 65 (79%) < 30 ng/mL. There was no significant difference between groups in achieving the cutoffs of 16 ng/mL or 20 ng/mL at 6 months; however, only 35% of the 400 IU group achieved the greater cutoff of 30 ng/mL compared with 74% in the 2000 IU group (P < .001). Baseline adjusted mean s-25OHD concentrations at 6 months were 9.6 ng/mL (95% CI 6.0-13.2, P < .001) greater in the 2000 IU than the 400 IU group. Disease activity was not affected by supplement dose. Few subjects exceeded safety marker cutoffs, and this did not differ by dose. CONCLUSIONS: At baseline, a high proportion of patients had a mean s-25OHD >20 ng/mL. 2000 IU vitamin D3/d is more effective in raising s-25OHD concentrations to > 30 ng/mL in children with CD than 400 IU/d, but both treatments were equally effective at achieving 16 or 20 ng/mL.