The Expression of MDM2 Gene Promoted Chondrocyte Proliferation in Rats with Osteoarthritis via the Wnt/ß-Catenin Pathway.

This study aimed to investigate the regulatory mechanism of MDM2 gene expression on cartilage cell proliferation in Osteoarthritis (OA) rats. For this purpose, 22 SD rats were randomly divided into normal control (10 cases) and treated (12 cases) groups. Treated group was used for OA modelling with the modified Hulth method. After a week, RT-PCR was used to detect MDM2 in cartilage tissue of rats, Wnt 1, Wnt 3 a, Wnt 10 b and ß-catenin genes mRNA expression. Rat chondrocytes were isolated and cultured, and the recombinant eukaryotic expression vector pcDNA3.1 myc-siRNA-MDM2-ß-catenin and co-expression plasmid pcDNA3.1 myc-siRNA-MDM2-ß-catenin was used to transfect chondrocytes and the proliferation and related gene expression levels of the transfected chondrocytes were detected by MTT method and RT-PCR. The results showed that compared with the control group, MDM2, Wnt 1, Wnt 3 a, Wnt 10b and ß-catenin genes in OA rat cartilage constructed by Hulth method were increased (p<0.05). The pcDNA3.1 myc-beta-catenin transfection slowed down the proliferation of OA chondrocytes, different from the non-transfected OA group (p<0.001), and increased Wnt 1, Wnt 3a, Wnt 10b and ß-catenin genes expression compared with the Control group (p<0.05), but did not affect the expression of MDM2. The transfection of siRNA-MDM2 was opposite to pcDNA3.1 myc-ß-catenin. The co-expression plasmid pcDNA3.1 myc-siRNA-MDM2-beta-catenin transfection did not affect the proliferation of OA chondrocytes. In general, the high expression of MDM2 in OA rats restricts the proliferation of chondrocytes, which may be related to the main pathogenesis of the occurrence and development of OA in vivo, and the regulation of MDM2 on the proliferation of chondrocytes may be achieved through the Wnt/ ß-catenin pathway.

Grouper (Epinephelus coioides) TCR signaling pathway was involved in response against Cryptocaryon irritans infection.

T cell activation is a complicated process accompanying with the activation of T cell receptor (TCR) signaling pathway, which is not well described in teleost fish. The initiation of this pathway depends on the interaction of membrane TCR co-receptors (e.g. CD4/8, CD3 and CD45) and a series of cytoplasmic protein tyrosine kinases (e.g. Lck, Fyn and ZAP70). Cyptocaryon irritans is a ciliate pathogen of marine fish white spot disease causing huge economic lost in marine aquaculture. This parasite can infect fish gill and skin and is considered to be a good pathogen model for fish gill and skin mucosal immunity. Our previous studies showed the locally mucosal antibody response was important for fish defense against this parasite. While how TCR signaling pathway involved in T cell activation to help B cell activation in C. irritans infected fish is still not known. In the present study, we cloned a grouper TCR co-receptor gene EcCD3ε (537 bp) and its three kinase genes, including EcLck (1512 bp), EcFyn (1605 bp) and EcZAP70 (1893 bp). Homology analysis showed that they all shared the highest identity with corresponding genes from Takifugu rubripes (EcCD3ε 41%, EcLck 88%, EcFyn 98% and EcZAP70 93%), and their conserved motifs involved in the signaling transduction were analyzed. The tissue distribution analysis showed these four genes were high expressed in thymus, and it is interesting to find their comparative high expression in skin, gill and midgut mucosal immune tissues. In C. irritans infected grouper, the expression of three TCR co-receptors (EcCD4-1, EcCD3ε and EcCD45) and three kinases (EcLck, EcFyn and EcZAP70) was tested in skin, gill, head kidney and spleen at 0, 12 h, 24 h, 2 d, 3 d, 5 d and 7 d. All six genes were significantly up-regulated in skin at most tested time points, which indicate the possibility of skin local T cell activation to support the local antibody response. Compared to three TCR co-receptors, significantly up-regulation of three kinases were seen in the spleen, and the spleen fold changes of these three kinases were much higher than head kidney, which indicates spleen maybe the major systematic immune organs for T cell activation in C. irritans infected fish.

Aerobic Dimerization of Enediyne Compounds: Construction of Naphthalene Frameworks.

The first bimolecular oxygenative annulation of enediyne compounds leading to naphthalene frameworks has been developed by using Pd(OAc)2 as the catalyst in the presence of NaI under O2 (1 atm). This reaction provided efficient access to a class of symmetric core-annulated naphthalenes by the homoannulation of enediyne-imides. Intriguingly, the crossover annulation of enediyne-imides and other functionalized enediynes could also be achieved by the same catalytic system, resulting in the formation of several unsymmetrical naphthalene derivatives. Preliminary mechanistic investigation using (18) O isotopic labelling and radical scavengers indicated that radical oxygen incorporation cascades might be involved in this conversion.

Palladium/copper-catalyzed aerobic intermolecular cyclization of enediyne compounds and alkynes: interrupting cycloaromatization for (4 + 2) cross-benzannulation.

A tandem coupling-ketooxygenation reaction of readily accessible enediyne-carboxylic compounds with inner alkynes has been developed that utilizes the PdCl2/CuBr2 catalytic system under an O2 atmosphere and assembles a class of isoindolinones and o-acylbenzoic acids. The two oxygen atoms are regioselectively incorporated into enediyne units at the 1- and 6-positions from atmospheric molecular oxygen and H2O, respectively, during the present process. This study uncovered a formal [4C + 2C] benzannulation-diketonization of enediynes and alkynes via a coupling and decoupling strategy.

A bi-directional segmentation method for prostate ultrasound images under semantic constraints.

Due to the lack of sufficient labeled data for the prostate and the extensive and complex semantic information in ultrasound images, accurately and quickly segmenting the prostate in transrectal ultrasound (TRUS) images remains a challenging task. In this context, this paper proposes a solution for TRUS image segmentation using an end-to-end bidirectional semantic constraint method, namely the BiSeC model. The experimental results show that compared with classic or popular deep learning methods, this method has better segmentation performance, with the Dice Similarity Coefficient (DSC) of 96.74% and the Intersection over Union (IoU) of 93.71%. Our model achieves a good balance between actual boundaries and noise areas, reducing costs while ensuring the accuracy and speed of segmentation.

Acromial approach for treating glenoid fractures: A report of two cases and a literature review.

Surgery is usually recommended for displaced glenoid fractures, with open reduction and internal fixation as the standard operative treatment. Three approaches have been recommended in the reduction of glenoid fractures: Anterior, posterior and combined; however, a traditional approach may be difficult due to a high position or a comminuted Ideberg type III fracture. The combined approach results in a longer incision and more soft tissue injury when associated with an acromial fracture. The present study describes two complicated glenoid fractures: One case was a comminuted Ideberg type III fracture associated with an Ogawa type II acromial fracture; the second case was an Ideberg type IV fracture with associated superior shoulder suspensory complex injuries. In these cases, the acromial approach was modified to achieve satisfactory exposure and fixation of the complicated fracture. After a 1-year follow-up, the patients had a satisfactory outcome.

Pd-catalyzed branching cyclizations of enediyne-imides toward furo[2,3-b]pyridines.

The convergent synthesis of a class of enediyne-imides as well as their palladium-catalyzed branching cyclizations, which can be accomplished in two ways leading to a set of polysubstituted furo[2,3-b]pyridines upon using the N-tosyl carboxamide moiety as an N,O-bisnucleophile, are presented.

Three-component assembly of conjugated enyne scaffolds via E-selective olefination of ynals.

Benefited by the accessible ynamido-lithium intermediates Ib from a Cu-catalyzed azide-alkyne cycloaddition in the presence of stoichiometric amounts of LiOH, a mild and flexible three-component route to conjugated enyne scaffolds was successfully achieved via a formal E-selective olefination strategy.