Knockdown of PRMT1 suppresses the malignant biological behavior of osteosarcoma cells and increases cisplatin sensitivity via c-Myc-mediated BCAT1 downregulation.

Increasing evidence indicated that protein arginine methyltransferase-1 (PRMT1) is an oncogene in multiple malignant tumors, including osteosarcoma (OS). The aim of this study was to investigate the underlying mechanism of PRMT1 in OS. The effects of PRMT1 or BCAT1, branched-chain amino acid transaminase 1 (BCAT1) on OS cell proliferation, invasion, autophagy, and apoptosis in vitro were examined. Moreover, molecular control of PRMT1 on c-Myc or transactivation of BCAT1 on c-Myc was assessed by chromatin immunoprecipitation and quantitative reverse transcription PCR assays. The effects of PRMT1 in vivo were examined with a xenograft tumor model. The results showed that PRMT1 was potently upregulated in OS tissues and cells. Upregulation of PRMT1 markedly increased OS cell proliferation and invasion in vitro and reduced cell apoptosis, whereas PRMT1 silencing showed the opposite effects. Cisplatin, one of the most effective chemotherapeutic drugs, improved cell survival rate by inducing the expression of PRMT1 to downregulate the cisplatin sensitivity. Meanwhile, the cisplatin-induced upregulation of PRMT1 expression caused dramatically autophagy induction and autophagy-mediated apoptosis by inactivating the mTOR signaling pathway, which could be reversed by 3-methyladenine, an autophagy inhibitor, or PRMT1 silencing. PRMT1 could activate c-Myc transcription and increase c-Myc-mediated expression of BCAT1. Furthermore, BCAT1 overexpression counteracted the effects of PRMT1 knockdown on cell proliferation, invasion, and apoptosis. Of note, deficiency of PRMT1 suppressed tumor growth in vivo. PRMT1 facilitated the proliferation and invasion of OS cells, inhibited cell apoptosis, and decreased chemotherapy sensitivity through c-Myc/BCAT1 axis, which may become potential target in treating OS.

LINC00641 impeded the malignant biological behaviors of papillary thyroid carcinoma cells via interacting with IGF2BP1 to reduce GLI1 mRNA stability.

Dysregulation of long intergenic non-protein coding RNA 00,641 (LINC00641) is associated with the malignancy progression of multiple cancers, including thyroid carcinoma. The current study aimed to determine the role of LINC00641 in papillary thyroid carcinoma (PTC) and the underlying mechanism. We found that LINC00641 was downregulated in PTC tissues and cells(p < 0.05), and overexpression of LINC00641 inhibited PTC cell proliferation and invasion, and induced apoptosis(p < 0.05), while silencing LINC00641 promoted the proliferation and invasion in PTC cells, and inhibited cell apoptosis(p < 0.05). Furthermore, we found that Glioma-associated oncogene homolog 1 (GLI1) expression was negatively correlated with LINC00641 expression in PTC tissues (r2 = 0.7649, p < 0.0001), and silencing GLI1 inhibited PTC cell proliferation and invasion, and induced apoptosis(p < 0.05). Meanwhile, RNA immunoprecipitation (RIP) and RNA pull-down assays confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) bound to LINC00641 as an RNA binding protein, and overexpression of LINC00641 destabilized GLI1 mRNA by competitively binding to IGF2BP1. Rescue experiments revealed that overexpression of GLI1 restored the inhibitory effect of LINC00641 overexpression on activation of the AKT pathway, as well as PTC cell proliferation and invasion, and counteracted the induction of cell apoptosis by LINC00641 overexpression. Finally, in vivo experimental results showed that overexpression of LINC00641 markedly suppressed tumor growth and reduced expression of GLI1 and p-AKT in xenograft tumor mice(p < 0.05). In summary, this study highlighted that LINC00641 plays a critical role in the malignant biological progression of PTC by regulating the LINC00641/IGF2BP1/GLI1/AKT signaling pathway, which may serve as a potential therapeutic target for PTC.

Adaptive optimal trajectory tracking control of AUVs based on reinforcement learning.

In this paper, an adaptive model-free optimal reinforcement learning (RL) neural network (NN) control scheme based on filter error is proposed for the trajectory tracking control problem of an autonomous underwater vehicle (AUV) with input saturation. Generally, the optimal control is realized by solving the Hamilton-Jacobi-Bellman (HJB) equation. However, due to its inherent nonlinearity and complexity, the HJB equation of AUV dynamics is challenging to solve. To deal with this problem, an RL strategy based on an actor-critic framework is proposed to approximate the solution of the HJB equation, where actor and critic NNs are used to perform control behavior and evaluate control performance, respectively. In addition, for the AUV system with the second-order strict-feedback dynamic model, the optimal controller design method based on filtering errors is proposed for the first time to simplify the controller design and accelerate the response speed of the system. Then, to solve the model-dependent problem, an extended state observer (ESO) is designed to estimate the unknown nonlinear dynamics, and an adaptive law is designed to estimate the unknown model parameters. To deal with the input saturation, an auxiliary variable system is utilized in the control law. The strict Lyapunov analysis guarantees that all signals of the system are semi-global uniformly ultimately bounded (SGUUB). Finally, the superiority of the proposed method is verified by comparative experiments.

The Relationship Between Chinese College Student Offspring's Physical Activity and Father Physical Activity During COVID-19 Pandemic.

The purpose of this study was to evaluate the relationship between the physical activity of Chinese college students and the physical activity of their parents. This relationship was examined by linear regression. The results showed that (1) the physical activities of China's college students will be refurbished and used for the parents. The offspring of COVID-19's later generation sports population showed that the offspring's physical activity was not broken during the later stage of the epidemic, and the coefficient of promotion (r = 1.515) (p < 0.01) of the offspring's participation in the physical activities was. (2) The increase or decrease of parents' sports population is affected by their children's occupation. Therefore, it shows the dynamic role of individuals and the two-way nature of socialization in the process of socialization. With the transformation from traditional society to modern society, promoting college students' physical activities can increase parents' physical activities and improve the level of social physical activities.

Circular RNA VMA21 ameliorates IL-1ß-engendered chondrocyte injury through the miR-495-3p/FBWX7 signaling axis.

This study explored the function of circular RNA VMA21 (circVMA21) in osteoarthritis (OA). IL-1ß inducement reduced the expression of circVMA21 in C28/I2 cells and human primary chondrocytes. Forced expression of circVMA21 heightened cell viability and attenuated cell apoptosis, accompanied by upregulation of Bcl-2, and downregulation of Bax and C-caspase-3 in C28/I2 cells in response to IL-1ß exposure. CircVMA21 overexpression diminished the expression of MMP1 and MMP13, augmented the expression of COL2A1, and impeded the production of IL-6, TNF-α, prostaglandin E2 (PGE2) and NO. CircVMA21 served as a competitive endogenous RNA by sponging miR-495-3p. F-box and WD40 domain protein 7 (FBWX7) was identified as a target of miR-495-3p. The compensation experiments affirmed that circVMA21-mediated protective effects on IL-1ß-irritated chondrocytes through the miR-495-3p/FBWX7 axis. The role of circVMA21 was also confirmed in an OA rat model. Collectively, these findings revealed a protective effect of circVMA21in OA by intercepting the miR-495-3p/FBWX7 crosstalk.

Chinese Residents' Subjective Class Identity and Physical Activity Participation Mechanism.

The aim of the present study was to evaluate the association between participation in physical activity and subjective class identity of people in urban and rural areas of China. The effect of social class identity on residents' physical activity was tested using the Monte Carlo method. There is a positive correlation between physical activity and the subjective class identity of urban and rural residents (r = 0.351, p < 0.01). It has been also seen that subjective class identity can significantly improve residents' physical activity. The path coefficient of subjective class identity to residents' physical activity was 0.12 (p < 0.003). Therefore, national and local governments should promote the equalization of physical activities by providing public services and government transfer payments in urban and rural areas, improve the physical activity by improving subjective class identity and promote social progress.

LncRNA TUG1 ameliorates diabetic nephropathy via inhibition of PU.1/RTN1 signaling pathway.

Diabetic nephropathy (DN) is a leading cause of end-stage renal failure. The study aimed to investigate whether long noncoding RNA taurine-upregulated gene 1 (TUG1) can ameliorate the endoplasmic reticulum stress (ERS) and apoptosis of renal tubular epithelial cells in DN, and the underlying mechanism. The DN mouse model was established by streptozocin injection, and the human renal tubular epithelial cell line HK-2 was treated with high glucose (HG) to mimic DN in vitro. The molecular mechanism was explored through dual-luciferase activity assay, RNA pull-down assay, RNA immunoprecipitation (RIP), and chromatin immunoprecipitation (CHIP) assay. The expression of TUG1 was significantly decreased in the renal tubules of DN model mice. Overexpression of TUG1 reduced the levels of ERS markers and apoptosis markers by inhibiting reticulon-1 (RTN1) expression in HG-induced HK-2 cells. Furthermore, TUG1 down-regulated RTN1 expression by inhibiting the binding of transcription factor PU.1 to the RTN1 promoter, thereby reducing the levels of ERS markers and apoptosis markers. Meanwhile, TUG1-overexpression adenovirus plasmids injection significantly alleviated tubular lesions, and reduced RTN1 expression, ERS markers and apoptosis markers, whereas these results were reversed by injection of PU.1-overexpression adenovirus plasmids. TUG1 restrains the ERS and apoptosis of renal tubular epithelial cells and ameliorates DN through inhibition of transcription factor PU.1.

Hypoxia inducible factor-3α promotes osteosarcoma progression by activating KDM3A-mediated demethylation of SOX9.

Hypoxia/oxygen-sensing signally is closely associated with many tumor progressions, including osteosarcoma (OS). Previous research principally focused on the function of hypoxia-inducible factor (HIF)-1α and HIF-2α as the major hypoxia-associated transcription factors in OS, however, the role of HIF-3α has not been investigated. Our study found that HIF-3α was upregulated in OS tissues and cell lines. HIF-3α overexpression facilitated cell proliferation and invasion, and inhibited apoptosis, whereas HIF-3α knockdown showed the opposite results. Chromatin immunoprecipitation analysis revealed that lysine demethylase 3A (KDM3A) expression was transcriptionally activated by HIF-3α under hypoxia, and KDM3A occupied the SRY-box transcription factor 9 (SOX9) gene promoter region through H3 lysine 9 dimethylation (H3K9me2). Additionally, rescue results revealed that KDM3A or SOX9 overexpression reversed the effects of HIF-3α silence on cell functions. The Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway inhibitor cucurbitacin I suppressed the promotive effects of HIF-3α overexpression on cell proliferation, invasion and TAK2/STAT3 pathway. Finally, OS cell line MG-63 transfected with HIF-3α short hairpin RNA (HIF-3α shRNA) were subcutaneously injected into nude mice, and the results found that HIF-3α knockdown significantly inhibited the xenograft tumor growth of OS in vivo. In conclusion, this study reveals that HIF-3α promotes OS progression in vitro and in vivo by activating KDM3A-mediated SOX9 promoter demethylation, which may provide a potential therapeutic mechanism for OS.

ETV5 overexpression contributes to tumor growth and progression of thyroid cancer through PIK3CA.

AIMS: Thyroid cancer is a common endocrine malignancy and sex hormone plays an important role in it. We have previously shown that activation of estrogen receptor (ER) α promotes thyroid cancer cell proliferation and invasion. Here, we attempted to investigate the role of ETS variant 5 (ETV5) on estrogen drived thyroid malignancy. MAIN METHODS: Ten patients with follicular thyroid cancer were enrolled in this study. Cell proliferation and migration ability were analyzed by CCK-8 assay and cell migration assay, respectively. Chromatin immunoprecipitation-PCR and luciferase assay were conducted to analyze the relationship of ETV5 and PIK3CA. KEY FINDINGS: ETV5 is highly expressed in thyroid tissues from patients with follicular thyroid cancer as well as in FTC133 cells. 17b-estradiol or overexpression of ERα induced an increase in ETV5 protein level in FTC133 cells. Knockdown of ETV5 inhibited FTC133 cell proliferation, migration, and epithelial-mesenchymal transition, while 17b-estradiol could not correct this effect. Additionally, the level of PIK3CA was markedly decreased in ETV5 knockdown cells and had a positive correlation with ETV5 in thyroid cancer patients. Chromatin immunoprecipitation-PCR analysis and luciferase assay confirmed that ETV5 directly targeted PIK3CA and that ETV5 was bound to the promoter region of PIK3CA. In addition, PIK3CA overexpression abrogated ETV5-induced cell growth, migration and epithelial-mesenchymal transition. SIGNIFICANCE: ETV5 enhanced cell proliferation, migration, and epithelial-mesenchymal transition through the PIK3CA signaling pathway, indicating that ETV5 may be a therapeutic target in thyroid cancer.

Gastrodia elata attenuates inflammatory response by inhibiting the NF-κB pathway in rheumatoid arthritis fibroblast-like synoviocytes.

Gastrodia elata (GE), which belongs to the Orchidaceae family, was found to possess anti-inflammatory activity. However, the effect of GE on inflammatory response in rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) remains largely unknown. Thus, the aim of this study was to investigate the effects of GE on tumor necrosis factor-α (TNF-α)-induced inflammatory response in RA-FLS and the underlying molecular mechanism was also explored. Our results demonstrated that GE significantly attenuated TNF-α-induced IL-6 and IL-8 production in RA-FLS. GE also inhibited TNF-α-induced MMP-3 and MMP-13 expression in RA-FLS. Furthermore, pretreatment with GE significantly attenuated TNF-α-induced the expression of p-p65 and IκBα degradation in RA-FLS. In conclusion, this study demonstrated for the first time that GE attenuated inflammatory response by inhibiting the NF-κB pathway signaling in RA-FLS. Thus, GE might have a therapeutic potential towards the treatment of RA.

Overexpression of microRNA-210 promotes chondrocyte proliferation and extracellular matrix deposition by targeting HIF-3α in osteoarthritis.

The present study aimed to determine the effect of microRNA (miR)­210 on osteoarthritis (OA). The expression levels of miR­210, type I and X collagen (COL1A1 and COL10A1) and matrix metallopeptidase 13 (MMP13) in OA and normal chondrocytes were determined using reverse transcription­quantitative polymerase chain reaction analysis. The OA chondrocytes were transfected with an miRNA precursor for miR­210 or a negative control. After 3, 7, 14 and 21 days, the expression levels of miR­210 were examined, the proliferation of the OA chondrocytes were determined using an XTT assay and the protein levels of Ki67 and HIF­3α were analyzed by Western blotting. After 21 days, the mRNA and protein levels of COL1A1, COL10A1 and MMP13 were analyzed. Th present study demonstrated that the expression levels of miR­210 and COL1A1 were lower, and the expression levels of COL10A1 and MMP13 were higher in the OA chondrocytes, compared with the levels of expression in the normal chondrocytes. Overexpression of miR­210 significantly promoted the proliferation of OA chondrocytes and induced the protein expression of Ki67. In addition, miR­210 overexpression markedly increased the expression of COL1A1 expression, but decreased the expression levels of COL10A1 and MMP13. A luciferase reporter assay confirmed the direct interaction between miR­210 and hypoxia­inducible factor (HIF)­3α. miR­210 did not alter the mRNA expression of HIF­3α, however, it suppressed the protein expression of HIF­3α. Additionally, HIF­3α knockdown significantly promoted OA chondrocyte proliferation and increased the mRNA levels of COL1A1, whereas it decreased the mRNA levels of COL10A1 and MMP13. The results of the present study suggested that miR­210 may be a negative regulator of the progression of OA, which increases chondrocyte proliferation and prompts extracellular matrix deposition by directly targeting HIF­3α.

IQGAP1 modulates the proliferation and invasion of thyroid cancer cells in response to estrogen.

Thyroid cancer is an endocrine malignancy with a high incidence rate, which is affected by female hormones, particularly estrogens, in its growth and progression. IQ-domain GTPase-activating protein 1 (IQGAP1) is overexpressed in a range of types of cancer and is reported to interact with estrogen receptor α (ERα) in breast cancer cells. However, the association between IQGAP1 and ERα in thyroid cancer cells remains to be elucidated. In this study, the role of IQGAP1 in thyroid cancer cells was examined. The expression of IQGAP1 (190 kDa) was analyzed using western blot analysis, which indicated that IQGAP1 was overexpressed in thyroid cancer tissues and FTC133 cells. However, IQGAP1 knockdown in the FTC133 cells led to a significant downregulation in ERα transcriptional activity, cell proliferation, cell adhesion and cell invasion under 17ß-estradiol (E2) conditions. Furthermore, ERα knockdown inhibited the enhanced protein expression levels of phosphorylated ERK1/2 and cyclin D1, which were induced by the overexpression of IQGAP1. Co-immunoprecipitation was also performed in thyroid cancer cells and the results suggested that IQGAP1 directly interacted with ERα in the FTC133 cells and the co-transfected COS-7 cells. Taken together, these findings revealed that IQGAP1 may directly interact with ERα and serve as a signal integrator, mediating ERα transcriptional activity, cell proliferation and cell invasion during the progression of thyroid cancer.

Two-stage therapeutic utility of ectopically formed bone tissue in skeletal muscle induced by adeno-associated virus containing bone morphogenetic protein-4 gene.

BACKGROUND: The major disadvantage of using a stem cell-based bone morphogenetic protein-4 (BMP4) gene therapy for skull defect is the overgrowth of generated bone tissue in situ. In the present study, to overcome bony overgrowth of stem cell based-gene therapy, a new strategy of two-stage bone tissue engineering by an adeno-associated virus containing BMP4 gene (AAV-BMP4) gene therapy was used. METHODS: AAV-BMP4 was purposely implanted in the skeletal muscle of mice to generate ectopic bone tissues during the first stage. Next, the newly formed ectopic bone tissues were harvested and then transplanted to repair the mouse skull defect during the second stage. RESULTS: The results showed that skeletal muscle implantation of AAV-BMP4 yielded a large amount of new bone tissues. The ectopic bone tissues can be harvested as a bone graft and can successfully repair the mouse skull defect without any bony overgrowth in situ. CONCLUSION: The results indicate that the bone tissues purposely generated by AAV-BMP4 in the skeletal muscle may be a new alternative of bone grafting for clinical purposes.

Celecoxib Combined with Diacerein Effectively Alleviates Osteoarthritis in Rats via Regulating JNK and p38MAPK Signaling Pathways.

Osteoarthritis (OA) has long been a difficult to overcome joint disease for medical workers. However, there is still a lack of effective treatments for OA. In the present study, we aimed to evaluate the treatment effect of celecoxib (CLX) combined with diacerein (DC) on OA and delineate the underlying molecular mechanism. The OA model was established by using rats, and OA rats were treated with either CLX alone, DC alone, and CLX combined with DC. The results showed that, as compared with a single treatment of CLX or DC, CLX combined with DC markedly attenuated OA and inhibited the levels of inflammatory mediators interleukin-1ß and nitric oxide, improved bone cartilage metabolism, and suppressed chondrocyte apoptosis. Most importantly, CLX combined with DC significantly inactivated the c-Jun N-terminal kinases (JNK) signaling pathway by the inhibition of MEKK1 and MKK7, as detected by Western blot analysis. Furthermore, the protein expression of downstream genes of JNK, including activating-transcription factor (Atf-2), matrix metalloproteinase-13 (MMP-13), and cyclooxygenase (COX-2), were also significantly inhibited by CLX combined with DC as compared with single treatments. Furthermore, CLX combined with DC also effectively inhibits p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways. Taken together, our study suggests that CLX combined with DC has satisfactory treatment effects on OA via a stronger inhibitory effect on inflammatory signaling pathway.

Effect and mechanism of miRNA to osteosarcoma cell.

MicroRNA has proved to be low expression in many tumor cells. In addition, it was also proved that as a kind of cancer suppressor gene, miR-199a-3p in miRNA can affect the growth and invasion ability of tumor cells. This paper aims to discuss the effect of miRNA to osteosarcoma cell. It used synthetic mature miR-199a-3p sequence simulants to transfect osteosarcoma cell and took negative contrast sequence (NC mimics) transfection cell as negative contrast. After transfection, qRT-PCR was applied to detect the expression quantity of miR-199a-3p in every group. Western blot method was applied to detect the expression level of MCL-(1) protein and shear situation of PARP in groups of cells. Flow cytometry was used for detecting apoptosis rate of cells and the experimental result was made a statistical analysis. The result shows that in cells from experimental group of transfection miR-199a-3p sequence simulants, expression quantity of mi-R-199a-3p significantly increased while MCL⁻¹ protein expression decreased compared to control group. In addition, shear level of PARP protein and apoptosis rate of cells increased. The differences all had statistical significance (P<0.05). It was concluded that miR-199a-3p can effectively promote the apoptosis rate of osteosarcoma cells.

Endobronchial ultrasound-guided transbronchial needle aspiration in diagnosing intrathoracic tuberculosis.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that has enabled mediastinal and hilar lymph node assessment with a high sensitivity, but its role in the diagnosis of intrathoracic tuberculosis (TB) has not been established. METHODS: We prospectively studied 59 patients suspected of having TB with thoracic lymph node lesions or intrapulmonary lesions accessible by EBUS-TBNA at a clinical center for thoracic medicine from January 2010 to December 2011. Bronchoscopic findings, EBUS-TBNA procedures, pathologic findings, and microbiologic results were recorded. RESULTS: Of 59 eligible patients, 41 patients had TB, 5 had lung cancer, 7 had inflammation, and 6 had sarcoidosis. Sensitivity was 85%, specificity was 100%, positive and negative predictive values were 100% and 75%, respectively, and accuracy was 90% by EBUS-TBNA for TB. Pathologic findings were consistent with TB in 80% of patients (33 of 41), and in 27% (11 of 41) the smear was positive. A total of 37 patients with TB had cultures, of whom 17 (46%) were positive. There were 80 mediastinal and hilar lymph nodes and 5 intrapulmonary lesions that were biopsied in the 41 patients with TB. Multivariate logistic regression revealed that short-axis diameter was an independent risk factor associated with positive pathology, smear, and culture (p < 0.05). Additionally, pathology showing necrosis was an independent risk factor associated with a positive culture. CONCLUSIONS: Endobronchial ultrasound-guided transbronchial needle aspiration has a high diagnostic yield in the investigation of suspected intrathoracic TB by means of aspiration of intrathoracic lymph nodes and tracheobronchial wall-adjacent lung lesions.

Suzuki-Miyaura coupling of aryl iodides, bromides, and chlorides catalyzed by bis(thiazole) pincer palladium complexes.

Bis(thiazole) pincer palladium complexes showed efficient catalytic activity for the Suzuki-Miyaura coupling of aryl halides, allowing the synthesis of biaryls with very high turnover numbers and turnover frequencies. The complexes were successfully applied in the scalable and green synthesis of the key intermediates of bioactive LUF5771 and its analogues.

Mitochondrial genome sequencing of chondrocytes in osteoarthritis by human mitochondria RT2 Profiler™ PCR array.

Mitochondria are not only the main energy generators of the cell, but also mediate several critical biochemical processes such as apoptosis, proliferation and redox homeostasis. As such, mitochondrial dysfunctions can lead to a wide variety of human diseases, including cancer and osteoarthritis (OA). In OA, mitochondrial-associated signaling has been implicated in the molecular events leading to cartilage degradation, including oxidative stress, defective chondrocyte biosynthesis and growth responses, increased cytokine-induced chondrocyte inflammation and matrix catabolism, cartilage matrix calcification and increased chondrocyte apoptosis. Thus, the mitochondrial genome represents an attractive target for molecular therapy and OA research has focused on determining its role in chondrocyte metabolism and subsequent cartilage degradation. In this study, we analyzed the mitochondrial gene expression changes that characterize chondrocytes in OA using the Human Mitochondria RT² Profiler™ PCR Array. Twenty-six differentially expressed genes were identified that discriminated chondrocytes in OA from those in normal cartilage, including 17 upregulated and 9 downregulated genes. These genes represent diverse functional categories, including mitochondrial membrane polarization and potential, mitochondrial transport, small molecule transport, targeting proteins to the mitochondria, mitochondrial protein import, outer and inner membrane translocation, mitochondrial fission and fusion, mitochondrial localization and apoptosis. Western blot analysis confirmed that the p53 upregulated modulator of apoptosis (PUMA; encoded by the BB3 gene) was significantly upregulated in OA cartilage. In conclusion, our study generates a differential mitochondrial gene expression profile for chondrocytes in OA and demonstrates that mitochondrial genome dysregulation occurs in cartilage cells during OA. Finally, our results indicate that PUMA may be a new diagnostic and therapeutic target for OA.

Gene expression analyses of subchondral bone in early experimental osteoarthritis by microarray.

Osteoarthritis (OA) is a degenerative joint disease that affects both cartilage and bone. A better understanding of the early molecular changes in subchondral bone may help elucidate the pathogenesis of OA. We used microarray technology to investigate the time course of molecular changes in the subchondral bone in the early stages of experimental osteoarthritis in a rat model. We identified 2,234 differentially expressed (DE) genes at 1 week, 1,944 at 2 weeks and 1,517 at 4 weeks post-surgery. Further analyses of the dysregulated genes indicated that the events underlying subchondral bone remodeling occurred sequentially and in a time-dependent manner at the gene expression level. Some of the identified dysregulated genes that were identified have suspected roles in bone development or remodeling; these genes include Alp, Igf1, Tgf ß1, Postn, Mmp3, Tnfsf11, Acp5, Bmp5, Aspn and Ihh. The differences in the expression of these genes were confirmed by real-time PCR, and the results indicated that our microarray data accurately reflected gene expression patterns characteristic of early OA. To validate the results of our microarray analysis at the protein level, immunohistochemistry staining was used to investigate the expression of Mmp3 and Aspn protein in tissue sections. These analyses indicate that Mmp3 protein expression completely matched the results of both the microarray and real-time PCR analyses; however, Aspn protein expression was not observed to differ at any time. In summary, our study demonstrated a simple method of separation of subchondral bone sample from the knee joint of rat, which can effectively avoid bone RNA degradation. These findings also revealed the gene expression profiles of subchondral bone in the rat OA model at multiple time points post-surgery and identified important DE genes with known or suspected roles in bone development or remodeling. These genes may be novel diagnostic markers or therapeutic targets for OA.

Novel bis(azole) pincer palladium complexes: synthesis, structures and applications in Mizoroki-Heck reactions.

Two novel NCN-pincer complex precursors bearing frameworks of 2,6-bis(oxazol-4-yl)benzene (A) and 2-(thiazol-4-yl)-6-(oxazol-4-yl)benzene (B) were synthesized. Palladations of A and B afforded two new bis(azole) pincer complexes, [(A-κ(3)NCN)PdBr] (1) and [(B-κ(3)NCN)PdBr] (2). Both complexes were fully characterized by NMR, MS, DSC-TGA and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in a noncentrosymmetric orthorhombic space group Cmc2(1) (No. 36, Z=4). Complex 2 crystallizes in a centrosymmetric monoclinic space group P2(1)/n (No. 14, Z=4). Despite the similarity in their chemical formulas, the structures of the two complexes are subtly different: they are built up of two-dimensional supramolecular layers with identical topology, but stacked in different sequences, i.e., the layers in complex 1 are stacked in an AAAA-type fashion, while those in complex 2 are stacked in an alternating AA(-1)AA(-1) sequence (A denotes a layer; A(-1) stands for A's inversion symmetry equivalent). In addition, the complexes showed good catalytic activity toward Mizoroki-Heck reactions.