Liquid-like atoms in dense-packed solid glasses.

Revealing the microscopic structural and dynamic pictures of glasses is a long-standing challenge for scientists1,2. Extensive studies on the structure and relaxation dynamics of glasses have constructed the current classical picture3-5: glasses consist of some 'soft zones' of loosely bound atoms embedded in a tightly bound atomic matrix. Recent experiments have found an additional fast process in the relaxation spectra6-9, but the underlying physics of this process remains unclear. Here, combining extensive dynamic experiments and computer simulations, we reveal that this fast relaxation is associated with string-like diffusion of liquid-like atoms, which are inherited from the high-temperature liquids. Even at room temperature, some atoms in dense-packed metallic glasses can diffuse just as easily as they would in liquid states, with an experimentally determined viscosity as low as 107 Pa·s. This finding extends our current microscopic picture of glass solids and might help establish the dynamics-property relationship of glasses4.

[An investigation on serum antibody level of varicella-zoster virus in healthy population in Beijing].

Objective: To assess the level and trend of varicella-zoster virus (VZV) antibody among healthy population in Beijing in 2017, after the five-year implementation of the two doses varicella vaccination strategy in 2012, and to provide evidence for scientific evaluation of immunization strategy. Methods: A total of 2 144 subjects in ten age groups from 8 districts of Beijing city were recruited in this study using cross-sectional survey based on multi-stage cluster random sampling method. Serum samples were collected and VZV antibody was detected by ELISA. The influencing factors of antibody concentration and positive rate were analyzed and compared with the study in 2012. The antibody concentration and antibody positive rate were analyzed by nonparametric test and χ² test respectively. Results: The ratio of subjects with registered residence in Beijing city to other provinces was 1∶1. The ratio of male to female was 1∶1.08. The median concentration of VZV antibody was 341.4 (78.6, 1 497.8) mIU/ml, and the total antibody positive rate was 71.1% (1 524/2 144). There were significant differences in antibody positive rate (χ²=736.39, P<0.01) and antibody concentration (χ²=740.34, P<0.01) among different age groups. The antibody positive rate generally increased with age (χ²trend=7.32, Ptrend<0.01). Among 862 children under 14 years old, the antibody positive rate of two doses vaccination 72.8% (182/250) was significantly higher than that of one dose vaccination 51.9% (154/297) (χ²=25.14, P<0.01). There was significant difference between 1-4 years old group (χ²=11.71, P<0.01) and 10-14 years old group (χ²=5.95, P=0.02), but not in 5-9 years old group (χ²=3.00, P=0.07). Compared with the study in 2012, the antibody positive rate increased in 5-9 years old group (χ²=14.35, P<0.01) and decreased in 1-4 years old group (χ²=11.51, P=0.01) in 2017. Conclusion: The recommended varicella booster vaccination has significantly improved the VZV antibody level of children in Beijing city. In the future, it is necessary to explore a more optimized two doses varicella vaccination schedule for children in combination with epidemiological evidence.

[Epidemiological characteristics of Chlamydia pneumoniae in cases with acute respiratory infection in Beijing, 2015-2019].

Objective: To analyze the epidemiological characteristics of Chlamydia pneumoniae infection among patients with acute respiratory infection in Beijing from 2015 to 2019. Methods: The epidemiological data of acute respiratory infection patients from 35 sentinel hospitals in Beijing were collected by the respiratory pathogen surveillance system in Beijing. The clinical samples were collected to detect Chlamydia pneumoniae, and the sequence of the VD4 region of the ompA gene in positive samples was analyzed. Results: From January 2015 to December 2019, the overall positive rate of Chlamydia pneumoniae among patients with acute respiratory infection in Beijing was 0.34% (129/37 460). The positive rate of Chlamydia pneumoniae generally increased in March, reaching the peak in May, and started to drop in July, with a duration of about 5-8 months. The epidemic season in different years fluctuated by 1-2 months. The positive monthly rate of Chlamydia pneumoniae was no less than 0.30% in every epidemic season. The positive rate of Chlamydia pneumoniae was the highest in the 5-44 years old group and the highest in 10-14 year-olds. The risk of Chlamydia pneumoniae infection increased with age in patients younger than 25 years old and decreased in those older one aged than 25 years of age. The positive rates in male and female patients were 0.33% (68/20 830) and 0.37% (61/16 528), respectively, and there was no significant difference between the two groups (χ2=0.486, P=0.486). The positive rate of Chlamydia pneumoniae in patients with common pneumonia was higher than that in patients with upper pneumonia and severe pneumonia (χ2=36.797, P<0.01). Other respiratory pathogens were also detected in the Chlamydia pneumoniae samples, and the top four pathogens appeared as Haemophilus influenzae (15 cases), Streptococcus pneumoniae (13 cases), Rhinovirus (8 cases), and Stenotrophomonas maltophilia (7 cases). 101 strains of 129 Chlamydia pneumoniae positive samples were identified as type A by sequencing. Conclusions: The annual epidemic pattern of Chlamydia pneumoniae in Beijing, is unimodal, and the epidemic season generally appears from March to July. The seasonal characteristics of Chlamydia pneumoniae in Beijing can be used for the differential diagnosis of Chlamydia pneumoniae from other respiratory pathogens. Chlamydia pneumoniae is most common in people aged 5-44 years, and the primary genotype is type A. People aged 10-44 years old suffer the highest incidence. If the nucleic acid positive rate of Chlamydia pneumoniae exceeds 0.30% for two consecutive months, the high prevalence period of Chlamydia pneumoniae can be preliminarily expected. Chlamydia pneumoniae infection has a higher probability of progressing to severe pneumonia from general pneumonia.

[Clinical characteristics of patients infected with Chlamydia pneumoniae in Beijing from 2015 to 2019].

Objective: To aralyze the clinical characteristics of Chlamydia pneumoniae infection in Beijing. Methods: Based on Beijing Respiratory Pathogen Surveillance System, acute respiratory infection patients were recruited from 35 different types of sentinel hospitals in Beijing. Their epidemiological and clinical data were systematically collected and clinical specimens were also obtained. Nuclear acid testing was performed for 30 types of respiratory pathogens (including Chlamydia pneumoniae). The identified patients of Chlamydia pneumoniae infection were divided into two groups, the acute upper respiratory tract infection (AURI) group and pneumoniae group. The differences in clinical characteristics, laboratory examination and prognosis were compared by using independent sample t test, Mann-Whitney U test, χ2 test or Fisher's exact probability test. Results: A total of 119 patients of Chlamydia pneumoniae infection were included, including 12 patients in the AURI group and 107 patients in pneumoniae group. Chlamydia pneumoniae infection mainly occurred in people aged from 5 to 44 years, accounting for 81.5% (97/119). The three most common clinical symptoms were cough (92.4%, 110/119), fever (88.8%, 95/107), and sputum production (76.5%, 91/119). White blood cell counts increased in 39.3% (46/117) of patients. Neutrophile granulocyte proportion increased in 39.7% (46/116) of patients. Platelet count increased in 36.9% (41/111) of patients. An increase of the creatine kinase MB isoenzyme (CKMB) was observed in 12 pneumonia patients (24.5%, 12/49). Radiological examination showed that 90.6% (87/105) of patients in the pneumoniae group had pulmonary parenchymal changes; the lesion occurred most commonly in the lower right lung lobe (34.3%, 36/105) and the lower left lung lobe (27.6%, 29/105). Although 73.8% (79/107) of patients in the pneumoniae group were hospitalized, no case received intensive care unit or mechanical ventilation. As to outcomes, one patient developed respiratory failure and 6 patients suffered myocardial injury. No death was observed in this study. The median days of hospitalization and course of illness for pneumonia patients M(P25,P75) were 10.0 (7.0, 13.0) days and 18.0 (13.5, 22.0) days, respectively. Conclusion: Generally, Chlamydia pneumoniae infections in Beijing from 2015 to 2019 were mild, and the main clinical manifestations were cough, fever and sputum. However, most patients in the pneumoniae group caused by Chlamydia pneumoniae still required hospitalization but with a better outcome.

[The prognostic impact of diabetic mellitus and hyperglycemia during DLBCL treatment on patients with diffuse large B-cell lymphoma].

Objective: This study aims to investigate the clinical features and prognostic factors of patients with diffuse large B-cell lymphoma (DLBCL) and assess the prognostic value of diabetes mellitus (DM) and hyperglycemia during DLBCL treatment in DLBCL. Methods: The clinical data of 481 newly diagnosed DLBCL patients from January 1, 2009 to December 31, 2019 at Tianjin Medical University Cancer Institute and Hospital and Sun Yat-sen University Cancer Center were retrospectively collected, focusing on their blood glucose levels before and during treatment. Cox regression method was used for univariate analysis to assess prognostic factors, and the Kaplan-Meier method was used to draw survival curves to assess the prognostic value of DM and hyperglycemia during DLBCL treatment in patients with DLBCL. Results: Eighty-two (17.0%) patients had DM before DLBCL diagnosis and treatment, and 88 (18.3%) patients had at least one blood glucose increase during DLBCL treatment. Cox univariate analysis showed that age, Ann Arbor stage, international prognostic index, and DM were associated with overall survival (OS) and progression-free survival (PFS) (all P<0.05) . The pairwise comparison between the two groups showed that the OS (P=0.001) and PFS (P<0.001) of patients with pre-existing DM were significantly worse than those of patients without abnormal blood glucose. Moreover, the OS (P=0.003) and PFS (P<0.001) of patients with hyperglycemia during DLBCL treatment were significantly worse than those of patients without abnormal blood glucose. No significant difference exists between patients with DM and patients with hyperglycemia during DLBCL treatment (OS, P=0.557; PFS, P=0.463) . Additionally, patients with adequate glycemic control during chemotherapy had a better prognosis compared with patients with poor glycemic control (OS, P=0.037; PFS, P=0.007) . Conclusion: DM is an important factor affecting the prognosis of patients with DLBCL. Moreover, hyperglycemia during treatment is related to the poor prognosis of patients with DLBCL.

Local crystalline order features in disordered packings of monodisperse spheres.

A new tetrahedral structure model was developed for disordered sphere packings, including not only regular tetrahedron (T), but also quartoctahedron (Q) and bcc simplex (B), the tetrahedral building blocks in fcc, hcp and bcc crystal structures, respectively. Both geometric frustrated configurations and local configurations associated with crystalline order in disordered packings can be comprehensively characterized. It is found that with increasing packing fraction, the population of T, Q, and B increases. Moreover, the crystal-type local configurations formed by face-adjacent T, Q and B increases as packing fraction increases, which is more prevalent than the geometric frustrated ones formed by face-adjacent T. In addition, as packing fraction increases, the local density of irregular simplexes is found to increase more quickly than regular ones, playing more important roles in the density increase in disordered packings. These structure features are found to be intrinsic in the jammed random sphere packings with different friction coefficients, which is independent of interparticle friction and only determined by the packing fraction. Our findings provide new understanding for the structural nature of disordered packings and the underlying structural basis of the random close packing.

Orbital competition of Mn3+ and V3+ ions in Mn1+x V2-x O4.

The structural and magnetic properties of Mn1+x V2-x O4 (0 < x ⩽ 1) have been investigated by the heat capacity, magnetization, x-ray diffraction and neutron diffraction measurements, and a phase diagram of temperature versus composition was built up. For x ⩽ 0.3, a cubic-to-tetragonal (c > a) phase transition was observed. For x > 0.3, the system maintained the tetragonal lattice. Although the collinear and noncollinear magnetic transitions of V3+ ions were obtained in all compositions, the canting angles between the V3+ ions decreased with Mn3+-doping, and the ordering of the Mn3+ ions was only observed as x > 0.4. In order to study the dynamics of the ground state, the first principles simulation was applied to analyze not only the orbital effects of Mn2+, Mn3+, and V3+ ions, but also the related exchange energies.

SOCS3 overexpression enhances ADM resistance in bladder cancer T24 cells.

The article "SOCS3 overexpression enhances ADM resistance in bladder cancer T24 cells, by M.-Z. Li, D.-H. Lai, H.-B. Zhao, Z. Chen, Q.-X. Huang, J. Situ, published in Eur Rev Med Pharmacol Sci 2017; 21 (13): 3005-3011-PMID: 28742207" has been withdrawn due to misunderstandings among some authors (Dr. Dehui Lai and Dr. Haibo Zhao) concerning the submission of the article. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/13067.

Circular RNA circ-ABCB10 promotes the proliferation and invasion of thyroid cancer by targeting KLF6.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Circular RNA circ-ABCB10 promotes the proliferation and invasion of thyroid cancer by targeting KLF6, by X.-T. Han, J.-Q. Jiang, M.-Z. Li, Q.-M. Cong, published in Eur Rev Med Pharmacol Sci 2020; 24 (3): 1271-1277-DOI: 10.26355/eurrev_202002_20182-PMID: 32096158" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20182.

[Surveillance of immunization effectiveness and titer of type â and type â ¢ polio vaccine in Beijing before and after the adjustment of immunization strategy in 2012-2018].

Objective: To analyze the changing trend of polio vaccine immunization effectiveness and vaccine titer in Beijing in 2012, 2014, 2016 and 2018 before and after the adjustment of polio vaccine immunization program strategy. Methods: According to the convenient sampling method,the vaccination clinics of Chaoyang and Yanqing Districts in 2012, Fengtai and Daxing Districts in 2014, Tongzhou and Pinggu Districts in 2016, Dongcheng and Shunyi Districts in 2018 were selected as monitoring points. A total of 292 children were selected 4-8 weeks after the completion of 3 doses polio vaccine basic immunization which were 3 doses of trivalent oral poliovirus vaccine（tOPV）schedule before the strategy adjustment in 2012-2014 and 1 dose of inactivated poliovirus vaccine (IPV) following 2 doses of bivalent oral poliovirus vaccine (bOPV) sequential schedule after the adjustment in 2016-2018. About 1.0 ml blood samples were collected to detect type Ⅰ and Ⅲ neutralizing poliovirus antibody. A total of 9 oral poliovirus vaccines (8 vaccines in 2012) were selected from different sources of vaccine storage every year to test the vaccine titer using random number method. Results: The [M（P25，P75）] age of 292 children was 5 (5, 6) months, and the ratio of male to female was 1.04 (149/143). In 2012, 2014, 2016 and 2018, 66,72,68 and 86 children were investigated respectively. After basic immunization, antibody positive rates for type Ⅰ and Ⅲ poliovirus were 100%, except 98.61% (71) for type Ⅰ poliovirus in 2014. The neutralizing antibody titer of type Ⅰ and Ⅲ poliovirus was higher in 2016 and 2018 than that in 2012 and 2014 (P<0.001). The average titer of tOPV were (6.05±0.15) and (6.16±0.12) lgCCID50 per dose in 2012 and 2014. The average titer of bOPV were (6.88±0.21) and (6.26±0.14) lgCCID50 per 100 µl in 2016 and 2018 (P<0.001). Conclusion: Before and after the adjustment of polio vaccine immunization strategy in Beijing, the basic immunization success rate of the IPV-bOPV sequential immunization schedule was good as well as full tOPV schedule. The level of polio antibody produced by the IPV-bOPV sequential immunization schedule was higher. After adjustment, bOPV titer in 2016 was significantly higher than those before adjustment, while bOPV titer decreased significantly in 2018.

Observation of High-Frequency Transverse Phonons in Metallic Glasses.

Using inelastic neutron scattering and molecular dynamics simulations on a model Zr-Cu-Al metallic glass, we show that transverse phonons persist well into the high-frequency regime, and can be detected at large momentum transfer. Furthermore, the apparent peak width of the transverse phonons was found to follow the static structure factor. The one-to-one correspondence, which was demonstrated for both Zr-Cu-Al metallic glass and a three-dimensional Lennard-Jones model glass, suggests a universal correlation between the phonon dynamics and the underlying disordered structure. This remarkable correlation, not found for longitudinal phonons, underscores the key role that transverse phonons hold for understanding the structure-dynamics relationship in disordered materials.

Circular RNA circ-ABCB10 promotes the proliferation and invasion of thyroid cancer by targeting KLF6.

OBJECTIVE: Recent researches have proved that circular RNAs (circRNAs) play important roles in many diseases. Thyroid cancer is one of the most common malignant tumors worldwide. Therefore, the aim of this study was to investigate the role of circ-ABCB10 in thyroid cancer. PATIENTS AND METHODS: Circ-ABCB10 expression in 40 paired thyroid cancer tissues and adjacent normal tissues was monitored by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR). Subsequently, circ-ABCB10 was silenced or overexpressed in thyroid cancer cells. Function assays were conducted to explore the role of circ-ABCB10 in the proliferation and invasion of thyroid cancer in vitro. Furthermore, RT-qPCR and Western blot assay were performed to elucidate the potential underlying mechanism. RESULTS: Circ-ABCB10 expression was significantly higher in thyroid cancer tissues than that in adjacent tissues. The growth ability of thyroid cancer cells was significantly inhibited after circ-ABCB10 silence. However, the growth ability of thyroid cancer cells was remarkably promoted after circ-ABCB10 was overexpressed in vitro. Similarly, the invasion of thyroid cancer cells was significantly inhibited or promoted after circ-ABCB10 silence or overexpression, respectively. Besides, the expression of KLF6 was markedly up-regulated by the silence of circ-ABCB10. However, KLF6 expression was down-regulated by overexpression of circ-ABCB10. CONCLUSIONS: Circ-ABCB10 was first identified as a novel oncogene in thyroid cancer. Furthermore, it significantly enhanced the proliferation and invasion of thyroid cancer by targeting KLF6. Our findings suggested that circ-ABCB10 could be used as a potential therapeutic target in thyroid cancer.

[Clavien-Dindo classification of complications after complete mesocolic excision in laparoscopic radical resection of right hemicolon cancer and analysis on its influencing factors].

Objective: To investigate the Clavien-Dindo (CD) classification of complications after complete mesocolic excision (CME) in laparoscopic radical resection of right-sided hemicolon cancer and its influencing factors. Methods: A retrospective case-control study was performed. Inclusion criteria: (1) the adenocarcinoma located at colon from cecum to hepatic flexure; (2) laparoscopic right hemicolectomy with CME was completed. Exclusion criteria: (1) patients had severe organ dysfunction before operation; (2) tumor invaded adjacent organs or developed distant organ metastasis; (3) emergency surgery; (4) failure of laparoscopic surgery, and conversion to laparotomy; (5) without complete clinical data. Finally, clinical data of 141 patients in our hospital form March 2015 to February 2019 were retrospectively analyzed. CD grading standard was used to evaluate postoperative complications. Univariate and multivariate logistic regression analyse were used to analyze the factors that might affect the complications. Survival analysis was conducted by grouping the indicators with statistically significant difference in multivariate analysis. Kaplan-Meier method was used to draw the survival curve and log-rank test was used to analyze the difference. Results: Of the 141 patients, 89 were male and 52 were female with mean age of (61.8±11.0) years. All the operations completed successfully. A total of 37 postoperative complications were developed in 26 (18.4%) patients had postoperative 37 cases of complications, mainly including 7 delayed incision healing, 6 diarrhea, and 5 respiratory dysfunction. According to CD classification standard, grade I, II, and IV a complication rates were 40.5% (15/37), 56.8% (21/37), and 2.7% (1/37) respectively. Univariate analysis showed that age ≥ 65 years (χ(2)=4.338, P=0.037), BMI ≥ 28 kg/m(2) (χ(2)=5.971, P=0.015), and preoperative hemoglobin < 100 g/L (χ(2)=3.985, P=0.046) were risk factors of postoperative complications. Multivariate analysis testified that age ≥ 65 years (OR=7.991, 95%CI: 2.203 to 28.983, P=0.002) and body mass index (BMI) ≥ 28 kg/m(2) (OR=4.231, 95%CI: 1.034 to 17.322, P=0.045) were independent risk factors for complications after laparoscopic CME surgery for right-sided hemicolon cancer. All the patients were followed up for median time of 24 (1-48) months. The log-rank test showed that there were no significant differences in the cumulative survival rate between patients of age < 65 years and age ≥ 65 years (χ(2)=0.986, P=0.321), and between those with BMI < 28 kg/m(2) and BMI ≥ 28 kg/m(2) (χ(2)=0.370, P=0.543). Conclusions: The main complications after CME in laparoscopic radical resection of right hemicolon cancer are CD grade I and II. Elderly and obesity are independent risk factor for postoperative complications. Before the operation, reasonable preventive measures should be taken for the elderly and the obese in order to reduce postoperative complications.

[DNA barcoding of 4 species of cheyletid mites based on COI and 18S rRNA gene sequences].

OBJECTIVE: To analyze the sequences of mitochondrial cytochrome C oxidase subunit I gene (COI) and 18S ribosomal RNA gene (18S rRNA), so as to identify the feasible DNA barcodes for 4 species of cheyletid mites and improve the DNA barcoding database for cheyletid mites. METHODS: Cheyletid mite samples were collected from small-scale flour mills in Fuyang, Wuhu and Tongling cities of Anhui Province from May 2018 to July 2019, extracted and morphologically identified. Then, genomic DNA was extracted from a single cheyletid mite, and the COI and 18S rRNA gene sequences were obtained by PCR amplification, cloning and sequencing. The obtained sequences were aligned using the BLAST software. Multiple sequence alignment was done using the software ClustalX version 1.83 using the known gene sequences from cheyletid mites. The genetic distance was calculated using the software MEGA X, and the phylogenetic tree was created using the maximum likelihood method. RESULTS: The DNA barcoding results of Cheyletus malaccensis, C. carnifex and Cheletomorpha lepidopterorum were consistent with the morphological identification, while no sequences pertaining to Eucheyletia reticulate were retrieved in the GenBank database. The proportions of A + T were 69.6% and 55.1% in the COI and 18S rRNA sequences of 4 cheyletid mites species, respectively, and the numbers of base substitutions were 137 and 46, respectively. There were 154 to 321 and 58 to 99 inter-species variation loci in the COI and 18S rRNA gene sequences of 4 cheyletid mites species, respectively, and the intra-species genetic distance was all 0.020 or less in the COI and 18S rRNA gene sequences of 4 cheyletid mites species, with inter-species genetic distance of 0.235 to 0.583 and 0.078 to 0.114, respectively. Phylogenetic analysis based on COI and 18S rRNA genes showed that all four species of cheyletid mites were clustered into a branch with a 100% supportive rate, which was consistent with the morphological identification. CONCLUSIONS: Mitochondrial COI gene is superior to 18S rRNA gene as DNA barcodes for 4 species of cheyletid mites, which is more suitable to be used to investigate the phylogenetic relationship of at genus and species levels.

[Survey of the acceptance status of HPV self-sampling screening in female population for cervical cancer].

Objective: To investigate the acceptance of HPV self-sampling mode in cervical cancer screening population and explore its feasibility. Methods: From March 5 to 15, 2018, researchers investigated women who participated in cervical cancer screening organized by Beijing Shunyi Women's and Children's Hospital in the form of questionnaires. Questionnaires were conducted on their acceptance status and the factors that affect the self-sampling experience. The specific contents of the questionnaires were as follows: (1) the experience of using self-sampling included operability, comfortable, sample time-consuming, bleeding or not after sampling; (2) psychological changes after self-sampling, including the willingness to accept self-sampling again, the worrying problems during self-sampling process. According to whether or not have operating video guidance, the self-sampling experience and psychological changes after self-sampling were compared. Results: (1) There were 1 375 women participated in the questionnaire survey, and 86.55% (1 190/1 375) of them thought the self-sampling was convenient, 78.40% (1 078/1 375) thought it was not uncomfortable, 88.58% (1 218/1 375) thought the sampling time was fast (less than 5 minutes), 94.04% (1 293/1 375) self-sampling without bleeding; and 83.27% (1 145/1 375) were willing to self-sampling for cervical cancer screening again, 85.82% (1 180/1 375) were afraid of inaccurate sampling. (2) Among the 1 375 women, 1 202 were in the video guidance group and 173 were in the non-guidance group. The self-sampling experience of women in video guidance group was better than those of non-guidance group in operability, comfortable, sampling time-consuming and bleeding after sampling. The proportion of women who willing to self-sampling again was higher than that of non-guidance group (86.69% vs 59.54%, respectively). The proportion of women who worried operating incorrectly was lower than that of non-guidance group (11.23% vs 32.37%, respectively). The differences were significant (all P<0.05). Conclusions: Self-sampling for HPV testing in cervical cancer screening is easy to operate and has little discomfort complaint. It is feasible in cervical cancer screening. Operational video guidance during the screening process could effectively improve the women's experience and willingness to self-sampling again in the future.

[MiR-222-3р Regulates the Proliferation and Differentiation of C2C12 Myoblasts by Targeting BTG2].

MiR-222-3р has been implicated in tumor cell proliferation and has an important role in the differentiation and maturation of myogenic cells. However, its role in skeletal myoblast proliferation is still unclear. In this study, we found that miR-222-3р expression increases initially and then decreases during C2C12 myoblast proliferation. Using synthetic miRNA mimics and inhibitors in gain- or loss-of-function experiments, we snowed that miR-222-3р overexpression in C2C12 cells promotes myoblast proliferation and represses myofiber formation, while miR-222-3р downregulation has the opposite effect. Using a prediction program, BTG2 was identified as a possible target gene of miR-222-3р. During myogenesis, miR-222-3р mimics repress BTG2 expression, while miR-222-3р inhibitors promote BTG2 expression. Using dual-luciferase reporter assay, we further demonstrated that miR-222-3р specifically targets BTG2. Additionally, we show that siRNA-mediated downregulation of BTG2 expression in C2C12 myoblasts promotes the proliferation and suppresses differentiation. In conclusion, we provide a novel insight into the mechanism by which miR-222-3р regulates the proliferation and differentiation of C2C12 myoblasts by targeting BTG2. This information contributes to our understanding of the role of miRNAs in skeletal muscle development.