LncRNA 4930581F22Rik promotes myogenic differentiation by regulating the ERK/MAPK signaling pathway.

The skeletal muscle is the largest organ in mammals and is the primary motor function organ of the body. Our previous research has shown that long non-coding RNAs (lncRNAs) are significant in the epigenetic control of skeletal muscle development. Here, we observed progressive upregulation of lncRNA 4930581F22Rik expression during skeletal muscle differentiation. Knockdown of lncRNA 4930581F22Rik hindered skeletal muscle differentiation and resulted in the inhibition of the myogenic markers MyHC and MEF2C. Furthermore, we found that lncRNA 4930581F22Rik regulates myogenesis via the ERK/MAPK signaling pathway, and this effect could be attenuated by the ERK-specific inhibitor PD0325901. Additionally, in vivo mice injury model results revealed that lncRNA 4930581F22Rik is involved in skeletal muscle regeneration. These results establish a theoretical basis for understanding the contribution of lncRNAs in skeletal muscle development and regeneration.

Influence of biological scaffold regulation on the proliferation of chondrocytes and the repair of articular cartilage.

PURPOSE: To investigate the effects of hard tissue engineering scaffold (the material is ß-TCP) with different micro-structures on the proliferation of chondrocytes, and the influence of its composite erythrocytes on the repair of articular cartilage defects. METHODS: Rabbit cartilage cells were on ß-TCP bioceramic scaffold with different micro-structures in vitro, the proliferation growth trend of chondrocytes within the scaffold was calculated, and a optimal micro-structure suitable for cartilage cell growth was determined. Composite chondrocytes were implanted into rabbit models of articular cartilage defects, and the repair situation was observed. RESULTS: the bioceramic scaffold with an inner diameter of 120 µm and an aperture of 500-630 µm was suitable for the growth of cartilage cells. Scaffold loaded with second generation of cartilage cell suspension got a top histological score of 20.76±2.13, which was closely similar to that of normal cartilage. CONCLUSION: When loaded with the second generation of cartilage cells, the ß-TCP biological ceramic scaffold with a pore size of 500-630 µm, and an inner diameter of 120 µm, shows a best repairing effect on animal articular cartilage defects.

[Progress on strategies to promote vascularization in bone tissue engineering].

With the continuous development of bone tissue engineering, a variety of emerging bone graft materials provided various methods for repairing bone defects. Early and rapid accomplishment of revascularization of materials interior after implantation of bone transplantation materials is a difficulty faced to bone tissue engineering. Blood vessels ingrowth provides the requisite netritional support for the regeneration reconstruction of bone tissue, for this reason, vascularization plays a significant role in bone tissue engineering. However,there is not a golden standard strategy of vascularization at present. Scaffold materials, cells and growth factors still are three indispensable elements in tissue engineering, and are cardinal points of the promoting vascularization strategies. Multiple growth factors or multiple cells combined with scaffolds, which are hot spots, have obtained excellent vascularization. This review focused on the comprehensive strategies for promoting the successful vascularization of tissue engineered scaffolds.

[Determination of trace element silver in animal serum, tissues and organs by microwave digestion-ICP-MS].

Nowadays, the silver is widely used in the biological field and its biological safety catches great attention. It is important to know the distribution of silver ions within the biological organism and the toxic threshold concentration in the tissue. Therefore, a highly sensitive method for measurement of trace amount of silver ion in the medical biological samples is needed. With its high sensitivity for detection of metal ions, inductively coupled plasma mass spectrometry (ICP-MS) method is well suited for quantification of trace amount of silver ion in such samples, but method development is still in its infancy. Consequently, a simple and convenient method for determination of trace amount of silver in the animal serum, tissues or organs was developed, in which the samples were subjected to the microwave digestion, followed by the ICP-MS analysis. To begin with, the samples of serum, muscle, bone marrow, bone, heart, liver, spleen, and kidney were sequently processed in 5 mL of HNO3 and 2 mL of H2O2 solution. Then the samples were completely digested by microwave with the power of 2 000 watts. The temperature was raised gradually by 3-step program. Moreover, the data achieved were reproducible and the method was time saving and especially for large amounts of sample processing. Then the digested solutions were diluted to constant volume. Finally, the concentration of 107Ag in the samples was analyzed by the method of ICP-MS under the optimized conditions. Element yttrium (Y) was used as the internal standard to compensate for matrix suppression effect and improve the accuracy of measurement. For one thing, the analytical results showed that the detection limit of the trace element 107Ag was 0.98 µg · kg(-1), and furthermore, the correlation coefficient of standard curve was 0.999 9. For another thing, the recovery rate of the silver element ranged from 98% to 107%, which was calculated according to measured quantity before adding standard, adding standard and measured quantity after adding standard. At the same time, the relative standard deviation (RSD) of the method was in the range of 2.0%-4.3%. The concentrations of element silver in animal serum, tissues and organs were determined by the aboved method. The obtained results showed that silver ions were mainly accumulated in the liver after they were intaken into the body. The results suggested that the microwave digestion-ICP-MS method could accurately determine the trace element Ag in the body. The method developed has good feasibility and is suitable for the determination of trace element Ag in various types of medical and biological samples, especially for large quantities of biological samples. The process has the advantages of easysample processing and it is simple and convenient. In addition, the accurate results could be obtained in a short time with high sensitivity. Last but not least, the method provides the guidance for the determination of trace elements in other biological samples.

Improved repair of bone defects with prevascularized tissue-engineered bones constructed in a perfusion bioreactor.

Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the non-vascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. [Orthopedics. 2014; 37(10):685-690.].

[Sequencing and analyses of the adenovirus polymerase gene in fecal samples of captively bred Rhesus macaques].

OBJECTIVE: In an attempt to study the moleculr characterization and epidemiology of simian adenoviruses in nonhuman primate (NHP) populations. METHODS: We examined a colony of captively bred rhesus macaques (Macaca mulatta) in China for the presence of adenoviral DNA in stool samples. This was done by using the PCR method that targeted the adenovirus polymerase gene, and the PCR positive fragments were cloned for sequencing and phylogenetic analyses. RESULTS: Among the 57 animals analyzed, fecal samples from 12 animals were positive for the presence of adenoviral DNA. The results suggested that the viral DNA clones were primarily segregated into two large groups: SAdV-6 (2 non-redundant sequences) and SAdV-7 (9 non-redundant sequences). In addition, there were three clones with more similarity to SAdV-1, SAdV-3 and HAdV-52 respectively. CONCLUSION: Our data confirmed the prevalence of adenoviral DNA in the feces of NHPs and revealed the adenoviruses in the gastrointestinal tract of the study animals. heterogeneity and phylogenetics of the adenoviruses in the gastrointestinal tract of the study animals.

[Expression of fibroblast activation protein in HBV related hepatocellular carcinoma].

OBJECTIVE: To analyze the gene expression level of fibroblast activation protein in HBV related hepatocellular carcinoma patients and discuss its clinical significance. METHODS: FAP gene expression in 33 hepatocellular carcinoma patients cancer tissues, peficancerous tissues, distant relative normal liver tissues and 13 normal liver tissues were examined by reverse transcription PCR; and real-time fluorescent quantitative PCR (qRT-PCR) was used to quantify their expression. RESULTS: FAP were expressed in all the tissues,the relative expression values in cancer tissues, peficancerous tissues and distant relative normal liver tissues were 5.14 +/- 6.69, 1.58 +/- 0.96, 1.63 +/- 0.94, respectively, the differences were statistically significant (F = 4.401, P < 0.05); and in TNM stage I, II, IIII, they were 2.89 +/- 3.35, 4.15 +/- 4.69, 10.09 +/- 9.51 respectively; in well-differentiated, differentiated and poorly differentiated hepatocellular carcinoma were 1.62 +/- 1.74, 3.84 +/- 3.79, 1.26 +/- 13.34 respectively. The differences were all statistically significant (P < 0.05). CONCLUSION: FAP may play an important role in the occurrence and development of HBV related hepatocellular carcinoma.

[The significance of antimitochondrial IgA and IgG in the diagnosis of primary biliary cirrhosis].

OBJECTIVE: To evaluate the sensitivity and the specificity of Anti-M2-3E ELISA for the detection of IgG- and IgA-specific isotypes of antimitochondrial antibody (AMA), and to investigate the significance of antimitochondrial IgA and IgG in the diagnosis of primary biliary cirrhosis (PBC). METHODS: Sera were collected from 107 PBC patients, 87 disease controls and 26 healthy controls, and the antimitochondrial antibodies (IgG and IgA) were detected using indirect immunofluorescence (IFL), Anti-PDC ELISA and Anti-M2-3E ELISA. RESULTS: The AMA IgG positive rate in PBC patients was 90.6% detected by Anti-M2-3E ELISA, which is significantly higher than that (81.3%) detected by IFL(t = 4.32, P < 0.05) and that (72.9%) detected by Anti- PDC ELISA (t = 6.03, P < 0.05). The AMA IgA was positive in 59 of the 107 PBC patients, and 99 of the 107 patients were positive for AMA IgG or/and IgA. 9 of the 20 IFL-negative patients were positive for AMA IgG as indicated by Anti-M2-3E ELISA, 11 of the 20 IFL-negative patients were positive for AMA IgG or/and IgA as indicated Anti-M2-3E ELISA. Compared to patients negative for IgG AMA, patients positive for IgG AMA had more severe histopathology and higher levels of ALP, IgG, and IgM. CONCLUSION: The IgG and IgA Anti- M2-3E ELISAs are more sensitive for the AMA detection than IFN and the Anti-PDC ELISA. The presence of AMA IgG is the characteristics of severe PBC.

[Using perfusion bioreactor for mesenchymal stem cell proliferation in large tricalcium phosphate scaffold].

OBJECTIVE: To investigate the feasibility of using perfusion culture bioreactor for bone mesenchymal stem cell proliferation in large scale beta-tricalcium phosphate (beta-TCP) scaffold. METHODS: In the dynamic perfusion culture group, the porous beta-TCP cylindrical scaffolds combined with the sheep mesenchymal stem cells were continuously perfused with the complete alpha-MEM medium by a peristaltic pump for 1, 2 and 4 weeks. While in the static culture group, the hybrid constructs were immersed in the medium without perfusion for 2 and 4 weeks. The cell proliferation and distribution were examined by the daily glucose consumption, the cell viability and undecalcified histological study. RESULTS: The daily glucose consumption increased with time. The increase was much more evident in the first 2 weeks than in the last 2 weeks. The daily glucose consumption was higher in the dynamic culture group than in the static culture group. The cell viability also increased with time. It was higher in the dynamic culture group. In comparison to 2-week culture, the cell viability was significantly higher after 4-week culture in the dynamic culture group (P < 0.05), while it was not significantly different after 4-week culture in the static culture group (P > 0.05). Under dynamic perfusion culture, the mesenchymal stem cells survived and proliferated through the scaffolds. However, the mesenchymal stem cells survived and proliferated only in the peripheral pores of the scaffolds under static culture. Histomorphometrical study indicated that there were much more cells in dynamic culture group than in the static group. The cell/pore rate was not significantly different between 2-week static culture and 4-week static culture (P > 0.05). However, the cell/pore rate was significantly higher after 4-week dynamic culture than after 2-week dynamic culture (P < 0.05). CONCLUSION: Perfusion culture permitted the persistent nutrition supply and gas exchange into the centre of large scaffold. This perfusion bioreactor makes the mesenchymal stem cells survive and proliferate through a large three-dimensional scaffold.

[The change of HBV nucleotide sequence during Adefovir dipivoxil treatment].

OBJECTIVE: To study the change of HBV nucleotide sequence during Adefovir dipivoxil treatment. METHODS: Serum samples were collected from 4 patients (numbers 228, 229, 230 and 233) with chronic hepatitis B (CHB) treated with PMEA. PCR amplification of full-length genomes, total genome clone, and sequencing and linkage of the HBV viruses were done with the serum samples collected before the therapy, and again on the 28th week, 52nd week and on the 92nd week of the therapy. Gene types and serum types were studied according to the HBV DNA sequence. The related biological information was analyzed, including the homogeneity and heterogeneity of the HBV DNA sequence before and during PMEA therapy, and variance of amino acids coded by HBV sequence. RESULTS: The gene types and serum types of HBV of the 4 patients were determined. Patient 228 was gene type C/serum type adrq+. Patient 229 was complex gene type B and C/complex serum type adw2 and adrq+. Patients 230 and 233 were both serum type adw2. The homogeneity of total gene sequence was 97.5% - 99.8% in one group of patients and 90.6% - 100% between groups in variant patients. The base mutation quantity of 52W was significantly higher than that of 28W and 92W. There was a common site of hotspot congregating mutation that existed in the P region. The target of PMEA was located in the P region encoding reverse transcriptase, which was generally very conservative. Therefore the mutations in this region were very significant. This might affect the activity of reverse transcriptase, leading to resistance to PMEA. CONCLUSION: We discovered some unusual aminophenol variations in the HBV genomes, which most probably are related to the HBV mutation that resulted in the developing resistance to PMEA.