3D,2D-QSAR study and docking of novel quinazolines as potential target drugs for osteosarcoma.

Background: Quinazolines are an important class of benzopyrimidine heterocyclic compounds with a promising antitumor activity that can be used for the design and development of osteosarcoma target compounds. Objective: To predict the compound activity of quinazoline compounds by constructing 2D- and 3D-QSAR models, and to design new compounds according to the main influencing factors of compound activity in the two models. Methods: First, heuristic method and GEP (gene expression programming) algorithm were used to construct linear and non-linear 2D-QSAR models. Then a 3D-QSAR model was constructed using CoMSIA method in SYBYL software package. Finally, new compounds were designed according to molecular descriptors of 2D-QSAR model and contour maps of 3D-QSAR model. Several compounds with optimal activity were used for docking experiments with osteosarcoma related targets (FGFR4). Results: The non-linear model constructed by GEP algorithm was more stable and predictive than the linear model constructed by heuristic method. A 3D-QSAR model with high Q2 (0.63) and R 2 (0.987) values and low error values (0.05) was obtained in this study. The success of the model fully passed the external validation formula, proving that the model is very stable and has strong predictive power. 200 quinazoline derivatives were designed according to molecular descriptors and contour maps, and docking experiments were carried out for the most active compounds. Compound 19g.10 has the best compound activity with good target binding capability. Conclusion: To sum up, the two novel QSAR models constructed were very reliable. The combination of descriptors in 2D-QSAR with COMSIA contour maps provides new design ideas for future compound design in osteosarcoma.

Rapamycin prevents the intervertebral disc degeneration via inhibiting differentiation and senescence of annulus fibrosus cells.

The effects of bleomycin and rapamycin on cellular senescence and differentiation of rabbit annulus fibrosus stem cells (AFSCs) were investigated using a cell culture model. The results showed that bleomycin induced cellular senescence in AFSCs as evidenced by senescence-associated secretory phenotype. The morphology of AFSCs was changed from cobblestone-like cells to pancake-like cells. The senescence-associated ß-galactosidase activity, the protein expression of P16 and P21, and inflammatory-related marker gene levels IL-1ß, IL-6, and TNF-α were increased in bleomycin-treated AFSCs in a dose-dependent manner. Rapamycin treatment decreased the gene expression of MMP-3, MMP-13, IL-1ß, IL-6, TNF-α, and protein levels of P16 and P21 in bleomycin-treated AFSCs. Furthermore, neither bleomycin nor rapamycin changed the ribosomal S6 protein level in AFSCs. However, the phosphorylation of the ribosomal S6 protein was increased in bleomycin-treated AFSCs and decreased in rapamycin-treated AFSCs. AFSCs differentiated into adipocytes, osteocytes, and chondrocytes when they were cultured with respective differentiation media. Rapamycin inhibited multi-differentiation potential of AFSCs in a concentration-dependent manner. Our findings demonstrated that mammalian target of rapamycin (mTOR) signaling affects cellular senescence, catabolic and inflammatory responses, and multi-differentiation potential, suggesting that potential treatment value of rapamycin for disc degenerative diseases, especially lower back pain.

TNF-α promotes osteoclastogenesis through JNK signaling-dependent induction of Semaphorin3D expression in estrogen-deficiency induced osteoporosis.

Tumor necrosis factor α (TNF-α)-induced osteoclast formation have been demonstrated to play an important role in the pathogenesis of estrogen deficiency-mediated bone loss, but the exact mechanisms by which TNF-α enhanced osteoclast differentiation were not fully elucidated. The class III semaphorins members were critical to regulate bone homeostasis. Here, we identified a novel mechanism whereby TNF-α increasing Semaphorin3D expression contributes to estrogen deficiency-induced osteoporosis. In this study, we found that Semaphorin3D expression was upregulated by TNF-α during the process of RANKL-induced osteoclast differentiation. Inhibition of Semaphorin3D in pre-osteoclasts could attenuate the stimulatory effects of TNF-α on osteoclast proliferation and differentiation. Mechanistically, blocking of the Jun N-terminal kinase (JNK) signaling markedly rescued TNF-α-induced Semaphorin3D expression, suggesting that JNK signaling was involved in the regulation of Semaphorin3D expression by TNF-α. In addition, silencing of Semaphorin3D in vivo could alleviate estrogen deficiency-induced osteoporosis. Our results revealed a novel function for Semaphorin3D and suggested that increased Semaphorin3D may contribute to enhanced bone loss by increased TNF-α in estrogen deficiency-induced osteoporosis. Thus, Semaphorin3D may provide a potential therapeutic target for the treatment of estrogen-deficiency induced osteoporosis.

Differential Characterization of Two Kinds of Stem Cells Isolated from Rabbit Nucleus Pulposus and Annulus Fibrosus.

Objective. Nucleus pulposus (NP) and annulus fibrosus (AF) are two main components of intervertebral disc (IVD). We aimed to figure out whether NP and AF also contain stem cells and whether these stem cells share common properties with chondrocytes and/or fibroblasts in their phenotypes or whether they are completely different types of cells with different characteristics. Design. The disk cells were isolated from AF and NP tissues of the same lumbar spine of the rabbits. The properties of these disk cells were characterized by their morphology, population doubling time (PDT), stem cell marker expression, and multidifferentiation potential using tissue culture techniques, immunocytochemistry, and RT-PCR. Results. Both disk cells formed colonies in culture and expressed stem cell markers, nucleostemin, Oct-4, SSEA-4, and Stro-1, at early passages. However, after 5 passages, AFSCs became elongated and NPSCs appeared senescent. Conclusion. This study indicated that IVD contains stem cells and the characteristics of AFSCs and NPSCs are intrinsically different. The findings of this study may provide basic scientific data for understanding the properties of IVD cells and the mechanisms of lower back pain.

Tumor necrosis factor alpha suppresses osteogenic differentiation of MSCs by inhibiting semaphorin 3B via Wnt/ß-catenin signaling in estrogen-deficiency induced osteoporosis.

The proinflammatory cytokines, especially tumor necrosis factor alpha (TNF-α), have been shown to inhibit osteogenic differentiation of mesenchymal stem cells (MSCs) and bone formation in estrogen-deficiency-induced osteoporosis, but the mechanisms of TNF-α impaired bone formation remain poorly understood. Semaphorins have been shown to regulate cell growth, cell migration, and cell differentiation in a variety of tissues, including bone tissue. Here, we identified a novel mechanism whereby TNF-α, suppressing Semaphorin3B expression contributes to estrogen-deficiency-induced osteoporosis. In this study, we found that TNF-α could decrease Semaphorin3B expression in osteogenic differentiation of MSCs. Overexpression of Semaphorin3B in MSCs attenuated the inhibitory effects of TNF-α on MSCs proliferation and osteoblastic differentiation. Mechanistically, activation of the Wnt/ß-catenin signaling markedly rescued TNF-α-inhibited Semaphorin3B expression, suggesting that Wnt/ß-catenin signaling was involved in the regulation of Semaphorin3B expression by TNF-α. Taken together, our results revealed a novel function for Semaphorin3B and suggested that suppressed Semaphorin3B may contribute to impaired bone formation by elevated TNF-α in estrogen-deficiency-induced osteoporosis. This study may indicate a therapeutic target gene of Semaphorin3B for osteoporosis.

[Repair of wounds with Achilles tendon exposure].

OBJECTIVE: To investigate the application and clinical result of flap in the repair of wounds with Achilles tendon exposure. METHODS: Between May 2006 and May 2010, 21 patients with Achilles tendon skin defects were treated with microsurgical reconstruction. There were 15 males and 6 females, aged 7-63 years with a median of 34 years. The defect causes included sport injury in 4 cases, wheel twist injury in 7 cases, crush injury in 5 cases, chronic ulcer in 3 cases, and Achilles tendon lengthening in 2 cases. The areas of wounds with Achilles tendon exposure ranged from 2 cm x 2 cm to 10 cm x 8 cm. After debridement, wounds were repaired with the medial malleolus fasciocutaneous flap (5 cases), sural neurocutaneous vascular flap (8 cases), foot lateral flap (2 cases), foot medial flap (2 cases), and peroneal artery perforator flap (4 cases). The size of the flaps ranged from 3 cm x 3 cm to 12 cm x 10 cm. The donor sites were either sutured directly or covered with intermediate split thickness skin grafts. The Achilles tendon rupture was sutured directly (2 cases) or reconstructed by the way of Abraham (2 cases). RESULTS: All flaps survived and wounds healed by first intention except 2 flaps with edge necrosis. Twenty-one patients were followed up 6-18 months (mean, 12 months). The flaps had good appearance and texture without abrasion or ulceration. The walking pattern was normal, and the two point discrimination was 10-20 mm with an average of 14 mm. The American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale assessment revealed that 10 patients had an excellent result, 7 had a good result, 3 had a fair result, and 1 had a poor result with an excellent and good rate of 81.0%. Fourteen cases could lift the heels with power; 5 cases could lift the heels without power slightly; and 2 cases could not lift the heels. CONCLUSION: The wounds with Achilles tendon exposure should be repaired as soon as possible by appropriate flap according to the condition of wound.

Application of a fasciocutaneous free flap for treatment of a severe soft tissue injury of the foot and ankle: a case report.

UNLABELLED: The authors report an unusual case wherein a fasciocutaneous free flap from an amputated upper limb was used to repair a severe soft tissue injury of the ipsilateral forefoot and ankle. After amputating the nonviable portions of the forefoot, a residual limb flap from the patient's forearm, pedicled with the brachial artery, was used to cover the lower extremity defect. Three years after the injury, the patient was able to maintain balance and ambulate without assistance on the reconstructed lower extremity. LEVEL OF CLINICAL EVIDENCE: 4.

[Clinical studies on treatment of patients with malignant spinal tumors by percutaneous vertebroplasty under guidance of digital subtraction angiography].

OBJECTIVE: To investigate the clinical therapeutic effects on malignant spinal tumors treated by percutaneous vertebroplasty (PVP) under the guidance of the digital subtraction angiography (DSA). METHODS: A retrospective analysis was performed in 196 patients (99 males and 97 females, aged 23-85 years, averaged 60.4 years) with malignant spinal tumors, who underwent the PVP treatment combined with standard chemotherapy and other comprehensive treatment from January 2002 to January 2005. The malignant spinal tumors had their origins as follows: lung cancer (66 cases), breast cancer (55 cases), liver cancer (19 cases), colon cancer (15 cases), stomach cancer (9 cases), prostate cancer (12 cases), multiple myeloma (16 cases), and malignant lymphoma of the spine (4 cases). The metastatic tumors involved the cervical vertebra (32 cases), thoracic vertebra (93 cases), lumbar vertebra (71 cases), and spinal column, including 1 vertebral segment (135 cases), 2 segments (50 cases), and more than 3 segments (11 cases). During the follow-up survey, changes in the visual analogue pain scale (VAS) and changes in the X-ray measurements of the average anterior height, midline height, and posterior height of the diseased vertebra were observed. RESULTS: The follow-up for 6 months to 3 years revealed that the percutaneous vertebroplasty on 279 vertebral segments had a success with an operational success rate of 100%. Bone cement was injected into the lesions 1-9 ml per segment of the spine. The postoperative X-ray and CT evaluations revealed that spinal stabilization was obtained in all the patients. After operation, 193 (98.5%)patients had an obvious decrease or disappearance of the pain in the lower back, and only 3 (1.5%) patients had no obvious improvement in the pain. There was a significant statistical difference in the VAS scores between before operation and after operation (P < 0.05). There were also significant statistical differences in the average anterior height of the diseased vertebra between before operation and after operation (15.71 +/- 2.80 mm vs. 16.61 +/- 3.01 mm), in the midline height (13.65 +/- 2.93 mm vs. 14.52 +/- 2.72 mm), and in the posterior height (23.67 +/- 2.81 mm vs. 23.70 +/- 3.13 mm, P < 0.05). The patients with lung or liver cancer had a mean survival time of 9 months after PVP; the patients with breast cancer, stomach cancer, prostate cancer, lymphoma, or other metastatic tumors had a mean survival time of 18 months. The patients with multiple myeloma had a mean survival time of 27 months. The differences were statistically different (P < 0.01). CONCLUSION: PVP under the guidance of the DSA is an easier operation with a small wound and few complications. It can effectively alleviate the patient's pain due to metastatic spinal tumor, stabilize the spine, improve the patient's quality of life, and reduce the incidence of paraplegia.