Low-expression of lncRNA-ANCR promotes tibial fracture healing via targeting RUNX2.

OBJECTIVE: To explore the role of long non-coding ribonucleic acid-anti-differentiation non-coding ribonucleic acid (lncRNA-ANCR) in tibial fracture healing in rabbits by regulating the runt-related transcription factor 2 (RUNX2) expression. MATERIALS AND METHODS: A total of 60 healthy adult rabbits were evenly divided into Control group (n=20), Fracture group (n=20), and Lnc group (n=20). Then, RUNX2 transfection, Real Time Polymerase Chain Reaction (PCR) assay and relevant instruments were carried out and used to determine the differences in dry weight, bone mineral density, bone mechanical strength, and RUNX2 expression in tibiae among three groups of rabbits. RESULTS: Comparison of the bone mineral density in rabbit tibiae among the three groups showed that the bone mineral density was significantly lower in Fracture group than that in Control group (p<0.05), and it was slightly higher in Lnc group than in Fracture group (p<0.05). The dry weight of the full-length tibiae in Fracture group was significantly decreased compared with that in Control group (p<0.05), and Lnc group had an increased dry weight of tibiae in comparison with Fracture group (p<0.05). The maximum load, flexural strength, elastic stress, elastic strain, elastic modulus, maximum stress, and maximum strain in Fracture group were lower than those in both Control group and Lnc group (p<0.05). Compared with those in Fracture group, the amount of new collagen was overtly increased in Lnc group, and that of mature collagen was decreased (p<0.05). The relative expression level of RUNX2 in tibial bone tissues was evidently lower in Fracture group than that in Control group (p<0.05), and it was markedly higher in Lnc group than that in Fracture group (p<0.05). CONCLUSIONS: Down-regulating lncRNA-ANCR activates and triggers the expression of RUNX2 that facilitates the growth and metabolism of bone tissues to play an important role in the repair of bone tissues and promote the healing of the tibial fracture.

A natural recombinant PRRSV between HP-PRRSV JXA1-like and NADC30-like strains.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major economically significant pathogen that has adversely affected China's swine industry. Currently, a novel type 2 PRRSV, called the NADC30-like strain, is epidemic in numerous provinces of China, and commercial vaccines provide limited protection for infected animals. The extensive recombination phenomenon among NADC30-like PRRSVs is identified as a unique molecular characteristic of the virus. However, our understanding of how recombination influences NADC30-like PRRSVs is largely inadequate. In this study, we analysed the genetic characteristics of a recombinant NADC30-like PRRSV (SC-d) and examined its pathogenicity compared with a non-recombinant NADC30-like PRRSV (SD-A19) and a highly pathogenic PRRSV (HuN4). SC-d has three discontinuous deletions in nsp2, consistent with NADC30 isolated from the United States in 2008. Furthermore, we identified four recombination breakpoints in the SC-d genome, which separated the SC-d genome into four regions (regions A, B, C and D). Regions A and C are closely related to the JXA1-like strain, one of the earliest Chinese HP-PRRSV strains, and regions B and D are closely related to the NADC30 strain. Moreover, SC-d inoculated piglets exhibited a persistent fever, moderate weight loss, mild thymus atrophy and obvious microscopic lung lesions. In summary, the recombinant NADC30-like PRRSV SC-d strain displayed a higher pathogenicity than the non-recombinant NADC30-like PRRSV SD-A19 strain; however, the pathogenicity of the NADC30-like PRRSV SC-d was lower compared with the HP-PRRSV HuN4 strain in piglets. Our findings demonstrate that recombination is responsible for the enormous genetic diversity and pathogenicity variance of the NADC30-like PRRSV in China. This study provides a theoretical basis for developing a more reasonable PRRSV control and prevention strategy.

Implications of microRNA-197 downregulated expression in esophageal cancer with poor prognosis.

The aim of this study was to investigate the significance of the microRNA miR-197 expression level in relation to clinicopathological factors and prognoses of esophageal cancer (EC). MicroRNA was extracted using the Taqman(®) MicroRNA Assay from 46 EC patients at the same tumor node metastasis (TNM) stage, but with different prognoses, who underwent surgery. Paracancerous normal tissues were used as controls. The correlation between miR-197 expression and clinicopathologic features was analyzed, and the significance of miR-197 as a prognostic factor and its relationship with survival was determined. miR-197 expression was lower in patients with poor prognosis than in those with good prognosis (P < 0.05). Kaplan-Meier analysis results showed that the miR-197 expression level is significantly correlated with survival time (P = 0.030), and that patients with higher expression of miR-197 had longer survival times. Cox multi-factor model analysis showed that patient prognosis (P = 0.001), tumor length (P = 0.010) and expression (P = 0.042), and survival time were significantly correlated, with corresponding risks of 9.183, 2.318, and 1.925, respectively. This study supports a role of miR-197 as an anti-oncogene and a biomarker for EC and its relationship with other prognostic factors and survival.

Identification of putative target genes for amplification within 11q13.2 and 3q27.1 in esophageal squamous cell carcinoma

BACKGROUND: Genomic aberration is a common feature of human cancers and also is one of the basic mechanisms that lead to overexpression of oncogenes and underexpression of tumor suppressor genes. Our study aims to identify frequent genomic changes and candidate copy number driving genes in esophageal squamous cell carcinoma (ESCC). METHODS: We used array comparative genomic hybridization to identify recurrent genomic alterations and screened the candidate targets of selected amplification regions by quantitative and semi-quantitative RT-PCR. RESULTS: Thirty-four gains and 16 losses occurred in more than 50 % of ESCCs. High-level amplifications at 7p11.2, 8p12, 8q24.21, 11q13.2-q13.3, 12p11.21, 12q12 and homozygous deletions at 2q22.1, 8p23.1-p21.2, 9p21.3 and 14q11.2 were also identified. 11q13.2 was a frequent amplification region, in which five genes including CHKA, GAL, KIAA1394, LRP5 and PTPRCAP were overexpressed in tumor tissues than paracancerous normal tissues. The expression of ALG3 at 3q27.1 was higher in ESCCs, especially in patients with lymph node metastasis. CONCLUSIONS: Target gene identification of amplifications or homozygous deletions will help to reveal the mechanism of tumor formation and explore new therapy method (AU)

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Identification of putative target genes for amplification within 11q13.2 and 3q27.1 in esophageal squamous cell carcinoma.

BACKGROUND: Genomic aberration is a common feature of human cancers and also is one of the basic mechanisms that lead to overexpression of oncogenes and underexpression of tumor suppressor genes. Our study aims to identify frequent genomic changes and candidate copy number driving genes in esophageal squamous cell carcinoma (ESCC). METHODS: We used array comparative genomic hybridization to identify recurrent genomic alterations and screened the candidate targets of selected amplification regions by quantitative and semi-quantitative RT-PCR. RESULTS: Thirty-four gains and 16 losses occurred in more than 50 % of ESCCs. High-level amplifications at 7p11.2, 8p12, 8q24.21, 11q13.2-q13.3, 12p11.21, 12q12 and homozygous deletions at 2q22.1, 8p23.1-p21.2, 9p21.3 and 14q11.2 were also identified. 11q13.2 was a frequent amplification region, in which five genes including CHKA, GAL, KIAA1394, LRP5 and PTPRCAP were overexpressed in tumor tissues than paracancerous normal tissues. The expression of ALG3 at 3q27.1 was higher in ESCCs, especially in patients with lymph node metastasis. CONCLUSIONS: Target gene identification of amplifications or homozygous deletions will help to reveal the mechanism of tumor formation and explore new therapy method.

Calreticulin promotes cell motility and enhances resistance to anoikis through STAT3-CTTN-Akt pathway in esophageal squamous cell carcinoma.

We have shown earlier that overexpression of Calreticulin (CRT) contributed to a poor prognosis for patients with esophageal squamous cell carcinoma (ESCC). Here, we have shown an important role of CRT in tumorigenesis through enhancing cell motility and anoikis resistance. SiRNA-mediated knockdown of CRT caused impaired cell migration, invasion and resistance to anoikis. Notably, CRT downregulation decreased the expression of Cortactin (CTTN), which has been previously reported as a candidate oncogene associated with anoikis through the PI3K-Akt pathway. In addition, Akt phosphorylation was abolished after CRT downregulation and its activation can be refreshed by CRT upregulation, suggesting that CRT-enhanced cell resistance to anoikis through the CRT-CTTN-PI3K-Akt pathway. Moreover, the CTTN mRNA level was decreased in CRT-siRNA cells, coupled with the inactivation of STAT3. Expression of both CTTN and p-STAT3 was reduced in tumor cells following incubation with the JAK-specific inhibitor, AG490. Chromatin immunoprecipitation assay showed direct binding of p-STAT3 to the conservative STAT3-binding sequences in CTTN promoter. Furthermore, overexpression of CTTN in CRT-downregulated ESCC cells restored its motility and resistance to anoikis. This study not only reveals a role of CRT in motility promotion and anoikis resistance in ESCC cells, but also identifies CRT as an upstream regulator in the CRT-STAT3-CTTN-Akt pathway.

A new approach to repairing cleft palate and acquired palatal defects with distraction osteogenesis.

Cleft palate (CP) is one of the most common human congenital deformities, and acquired palate defects after trauma or tumour resection are also common. In this study, distraction osteogenesis (DO) for CP and other palatal bone defects was evaluated. Twenty cats were assigned randomly to 3 groups of (1) 15, (2) 3 and (3) 2 cats. In groups 1 and 2, a rectangular ostectomy, in the posterior of the palatal bone shelf, was performed in the sagittal axis to establish the CP defect model. At the same time, a pure titanium intraoral distractor was fixed to molar teeth with brackets and to the palatal bone shelf across the defect with titanium miniscrews bilaterally. Four weeks later, a secondary transport disc (TD) osteotomy was performed, and gradual DO treatment started at 0.4mm twice a day, after 6 days of latency. DO was performed until the TD reached the opposite margin over the gap in 5-6 days. Three cats each of group 1 were killed at 2, 4, 6, 8 and 12 weeks after completion of DO. In group 2, the bone and soft-tissue defects were untreated until death 6 weeks later. Group 3 cats (control) were killed after 6 weeks. The TD successfully recombined with the opposite palatal bone stump, and proportional expansion of the overlay mucoperiosteal flap was achieved. Intramembranous bone formation was revealed: parallel collagen bundles gradually deposited on new bone trabeculae while the proliferative osteoblasts produced bone matrix. The bone defect was finally reconstructed by de novo osteogenesis. The control group was observed to have no spontaneous repairing. These results suggest that the CP defect was reconstructed by osteogenesis in situ, and the soft tissues expanded simultaneously to achieve functional correction. The intraoral distractor provided both effective distraction and stability.

Synthesis and electrochemical properties of phthalocyanine--fullerene hybrids

Phthalocyanines linked to C60 have been synthesized by two general strategies. One of them involves the addition of an azomethine ylide prepared in situ from a formyl phthalocyanine to C60, and the other one involves a statistical condensation of two substituted phthalonitriles, one of them bearing the C60 moiety covalently attached. These new phthalocyanine-fullerene dyads have been studied by cyclic voltammetry and Osteryoung square wave voltammetry, and inter- and intramolecular electronic interactions between the two electroactive subunits have been demonstrated.

Synthesis and properties of conjugated hybrid tetrathiafulvalene dimers

The synthesis of new hybrid tetrathiafulvalene (TTF) dimers (11a-c) has been carried out by a Wittig-Horner reaction of the respective phosphonate esters (10a-c) with 2-(tetrathiafulvalenylvinyl)-9, 10-anthraquinone (9) prepared by olefination of formyltetrathiafulvalene (7) and the phosphonium salt of anthraquinone 8. Electrochemical studies show that the dimers 11a-c mainly retain the electrochemical properties of both TTF and the pi-extended TTF components, and most importantly, intramolecular electronic interactions between the two moieties are observed by cyclic voltammetry and Osteryoung square wave voltammetry. Semiempirical PM3 calculations reveal an almost planar geometry for the TTF and the benzene ring connected through the vinyl spacer. These compounds can form stable charge-transfer complexes with 2, 3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) showing a stoichiometry of 1:3 (D:A). Attempts to electrocrystallize the dimeric donors with different counteranions are discussed.

Dithia-crown-annelated tetrathiafulvalene disulfides: synthesis, electrochemistry, self-assembled films, and metal ion recognition

The synthesis and electrochemistry of a series of tetrathiafulvalene (TTF) and dithia-crown-TTF derivatives attached with one or two disulfide group(s) 7a-f are reported. The self-assembled monolayers (SAMs) of these TTF disulfides on gold were prepared and characterized by reflection-absorption infrared spectroscopy. The SAMs are extremely stable under a wide variety of conditions and over extended periods of time and show remarkable electrochemical stability upon repeated potential scans. SAMs of the crown-TTF disulfides 7c,d,f can recognize alkali metal ions, and the process can be monitored following the electrochemical potential shift of the surface-confined TTF group.

Intramolecular electronic interactions in conjugated ferrocene-pi-extended-tetrathiafulvalene donor-pi-donor molecular hybrids

The synthesis of new hybrid ferrocene and pi-extended tetrathiafulvalene (TTF) donor(1)-pi-donor(2) molecular assemblies 16a-c has been carried out by a Wittig-Horner reaction of the respective phosphonate esters 15a-c with 2-(2-ferrocenylvinyl)-9, 10-anthraquinone (18) prepared by olefination of ferrocenecarboxaldehyde (14) and the anthraquinone phosphonium salt 17. Electrochemical studies show that the D(1)-pi-D(2) (D = donor) molecular assemblies 16a-c essentially retain the redox characteristics of both ferrocene and the pi-extended TTF components and the effects of solvent, temperature, scan rate, and working electrode are significant. Most importantly, pronounced intramolecular electronic interactions between the two donor moieties were observed by cyclic voltammetry and Osteryoung square wave voltammetry in both the ground and charged states. Semiempirical calculations support the electrochemical observations.