[Reference values of skeletal muscle mass for children in Nanjing area].

Objective: To establish the reference values and growth curves of skeletal muscle mass among children in the Nanjing area. Methods: A cross-sectional study was conducted with children who underwent physical examination at the Department of Child Health Care, Children's Hospital of Nanjing Medical University from 2020 January to 2022 September. Their height, weight, body fat mass and skeletal muscle mass were measured. Body mass index, percentage of body fat mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat were calculated. The associations between skeletal muscle mass indices and physical measurements index were analyzed through the Spearman correlation test. The Mann-Kendall test was used to assess the trend for skeletal muscle mass. Generalized additive models for location, scale and shape were used to construct percentile reference values and growth curves of male and female skeletal muscle mass indices at different ages. Results: A total of 32 690 children aged 4-14 years were enrolled in this study, including 19 912 boys (60.91%). Skeletal muscle mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat of boys and girls was 11.10 (8.40, 14.90) and 10.30 (7.90, 13.20) kg, 40.36% (37.01%, 43.13%) and 39.38% (36.43%, 41.88%), 6.70 (6.07, 7.52) and 6.33 (5.79, 7.00), 2.39 (1.46, 3.47) and 2.14 (1.45, 3.00) kg/m2, respectively. Skeletal muscle mass of both boys and girls was all positively associated with weight (r=0.97, 0.96), body mass index (r=0.68, 0.63) and percentage of body fat mass (r=0.40, 0.43) (all P<0.01). The reference values and growth curves showed that the percentage of skeletal muscle mass P50 ranged from 37.75%-44.61% in boys and from 36.22%-40.55% in girls. The relative skeletal muscle mass index P50 ranged from 5.80-9.68 kg/m2 in boys and from 5.57-7.98 kg/m2 in girls. The ratio of skeletal muscle to body fat P50 ranged from 1.86-2.67 in boys and from 1.29-2.41 in girls. There was an increasing trend with age for both boys and girls in the growth of skeletal muscle mass (Z=4.20, 3.75, both Ptrend<0.01), and increased slightly before 9 years of age and then increased rapidly until 14 years of age in both boys and girls. Conclusions: The skeletal muscle mass indices change with age and gender during childhood. Percentile reference values for pediatric skeletal muscle mass indices can be used to evaluate the muscular growth and development in children in the Nanjing area.

[Sacubitril/valsartan attenuates left ventricular remodeling and improve cardiac function by upregulating apelin/APJ pathway in rats with heart failure].

Objective: To investigate the effect and mechanism of sacubitril/valsartan on left ventricular remodeling and cardiac function in rats with heart failure. Methods: A total of 46 SPF-grade male Wistar rats weighed 300-350 g were acclimatized to the laboratory for 7 days. Rats were then divided into 4 groups: the heart failure group (n=12, intraperitoneal injection of adriamycin hydrochloride 2.5 mg/kg once a week for 6 consecutive weeks, establishing a model of heart failure); heart failure+sacubitril/valsartan group (treatment group, n=12, intragastric administration with sacubitril/valsartan 1 week before the first injection of adriamycin, at a dose of 60 mg·kg-1·d-1 for 7 weeks); heart failure+sacubitril/valsartan+APJ antagonist F13A group (F13A group, n=12, adriamycin and sacubitril/valsartan, intraperitoneal injection of 100 µg·kg-1·d-1 APJ antagonist F13A for 7 weeks) and control group (n=10, intraperitoneal injection of equal volume of normal saline). One week after the last injection of adriamycin or saline, transthoracic echocardiography was performed to detect the cardiac structure and function, and then the rats were executed, blood and left ventricular specimens were obtained for further analysis. Hematoxylin-eosin staining and Masson trichrome staining were performed to analyze the left ventricular pathological change and myocardial fibrosis. TUNEL staining was performed to detect cardiomyocyte apoptosis. mRNA expression of left ventricular myocardial apelin and APJ was detected by RT-qRCR. ELISA was performed to detect plasma apelin-12 concentration. The protein expression of left ventricular myocardial apelin and APJ was detected by Western blot. Results: Seven rats survived in the heart failure group, 10 in the treatment group, and 8 in the F13A group. Echocardiography showed that the left ventricular end-diastolic diameter (LVEDD) and the left ventricular end-systolic diameter (LVESD) were higher (both P<0.05), while the left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were lower in the heart failure group than in the control group (both P<0.05). Compared with the heart failure group, rats in the treatment group were featured with lower LVEDD and LVESD (both P<0.05), higher LVEF and LVFS (both P<0.05), these beneficial effects were reversed in rats assigned to F13A group (all P<0.05 vs. treatment group). The results of HE staining showed that the cardiomyocytes of rats in the control group were arranged neatly and densely structured, the cardiomyocytes in the heart failure group were arranged in disorder, distorted and the gap between cells was increased, the cardiomyocytes in the treatment group were slightly neat and dense, and cardiomyocytes in the F13A group were featured similarly as the heart failure group. Masson staining showed that there were small amount of collagen fibers in the left ventricular myocardial interstitium of the control group, while left ventricular myocardial fibrosis was significantly increased, and collagen volume fraction (CVF) was significantly higher in the heart failure group than that of the control group (P<0.05). Compared with the heart failure group, the left ventricular myocardial fibrosis and the CVF were reduced in the treatment group (both P<0.05), these effects were reversed in the F13A group (all P<0.05 vs. treatment group). TUNEL staining showed that the apoptosis index (AI) of cardiomyocytes in rats was higher in the heart failure group compared with the control group (P<0.05), which was reduced in the treatment group (P<0.05 vs. heart failure group), this effect again was reversed in the F13A group (P<0.05 vs. treatment group). The results of RT-qPCR and Western blot showed that the mRNA and protein levels of apelin and APJ in left ventricular myocardial tissue of rats were downregulated in heart failure group (all P<0.05) compared with the control group. Compared with the heart failure group, the mRNA and protein levels of apelin and APJ were upregulated in the treatment group (all P<0.05), these effects were reversed in the F13A group (all P<0.05 vs. treatment group). ELISA test showed that the plasma apelin concentration of rats was lower in the heart failure group compared with the control group (P<0.05); compared with the heart failure group, the plasma apelin concentration of rats was higher in the treatment group (P<0.05), this effect was reversed in the F13A group (P<0.05 vs. treatment group). Conclusion: Sacubitril/valsartan can partially reverse left ventricular remodeling and improve cardiac function in rats with heart failure through modulating Apelin/APJ pathways.

Glutaredoxins regulate maize inflorescence meristem development via redox control of TGA transcriptional activity.

Glutaredoxins (GRXs) are small oxidoreductases that can modify target protein activities through control of the redox (reduction/oxidation) state by reducing or glutathionylating disulfide bridges. Although CC-type GRXs are plant specific and play important roles in many processes, the mechanisms by which they modulate the activity of target proteins in vivo are unknown. In this study, we show that a maize CC-type GRX, MALE STERILE CONVERTED ANTHER1 (MSCA1), acts redundantly with two paralogues, ZmGRX2 and ZmGRX5, to modify the redox state and the activity of its putative target, the TGA transcription factor FASCIATED EAR4 (FEA4) that acts as a negative regulator of inflorescence meristem development. We used CRISPR-Cas9 to create a GRX triple knockout, resulting in severe suppression of meristem, ear and tassel growth and reduced plant height. We further show that GRXs regulate the redox state, DNA accessibility and transcriptional activities of FEA4, which acts downstream of MSCA1 and its paralogues to control inflorescence development. Our findings reveal the function of GRXs in meristem development, and also provide direct evidence for GRX-mediated redox modification of target proteins in plants.

Prognostic potentials of miRNA-19a-3p and PDCD5 in nasopharynx carcinoma.

OBJECTIVE: To determine expressions of MicroRNA-19a-3p (miRNA-19a-3p) and PDCD5 in nasopharyngeal carcinoma (NPC) tissues, and their prognostic potentials in NPC. PATIENTS AND METHODS: Expressions of miRNA-19a-3p and PDCD5 in NPC tissues and controls were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between expressions of miRNA-19a-3p and PDCD5 in NPC was evaluated by Pearson correlation test. Furthermore, potential influences of miRNA-19a-3p and PDCD5 on clinical features of NPC patients were assessed. Through 5-year follow-up, survival analysis in NPC patients was conducted by Kaplan-Meier method. Finally, factors influencing prognosis of NPC were determined using the Cox regression model. RESULTS: MiRNA-19a-3p was upregulated and PDCD5 was downregulated in NPC tissues. Pearson correlation test uncovered a negative correlation between expression levels of miRNA-19a-3p and PDCD5 in NPC tissues. MiRNA-19a-3p level was correlated with N classification and clinical stage in NPC patients, while PDCD5 level was correlated with T classification, pathological grade and clinical stage. Survival analysis showed poor prognosis in NPC patients expressing high level of miRNA-19a-3p or low level of PDCD5. Cox regression analysis illustrated that N2+3 classification, clinical stage III+IV, high level of miRNA-19a-3p and low level of PDCD5 were independent risk factors for the prognosis of NPC. CONCLUSIONS: MiRNA-19a-3p is upregulated and PDCD5 is downregulated in NPC tissues. High level of miRNA-19a-3p and low level of PDCD5 are unfavorable for the prognosis of NPC.

Grain boundary stability governs hardening and softening in extremely fine nanograined metals.

Conventional metals become harder with decreasing grain sizes, following the classical Hall-Petch relationship. However, this relationship fails and softening occurs at some grain sizes in the nanometer regime for some alloys. In this study, we discovered that plastic deformation mechanism of extremely fine nanograined metals and their hardness are adjustable through tailoring grain boundary (GB) stability. The electrodeposited nanograined nickel-molybdenum (Ni-Mo) samples become softened for grain sizes below 10 nanometers because of GB-mediated processes. With GB stabilization through relaxation and Mo segregation, ultrahigh hardness is achieved in the nanograined samples with a plastic deformation mechanism dominated by generation of extended partial dislocations. Grain boundary stability provides an alternative dimension, in addition to grain size, for producing novel nanograined metals with extraordinary properties.

[Effects and mechanisms of ursodeoxycholic acid on isoprenaline-Induced myocardial fibrosis in mice].

Objective: To investigate the effects and possible mechanisms of ursodeoxycholic acid (UDCA) on myocardial fibrosis in mice. Method: To observe the expression of transforming growth factor(TGF) -ß1, CTGF, MMPs and the degree of myocardial fibrosis, 61 male Kunming mice were randomly divided into normal group, low dose UDCA group, high dose of UDCA group, spironolactone group, and the control group.Isoproterenol (ISO) injection was given subcutaneously (30 d) to make the model of myocardial fibrosis.Corresponding anti-fibrosis drugs (UDCA or spironolactone) were given by gavage.HE staining and Masson staining were performed to explore the inflammation and fibrosis in the myocardium.The expression of collagen Ⅰ and collagen Ⅲ protein was detected by immunohistochemistry to evaluate the degree of fibrosis among the groups.Western blot was used to detect the expression of transforming growth factor, (TGF)-ß1, connective tissue growth factor (CTGF), matrix metalloproteinase (MMP)-2, -9, tissue inhibitor of metalloproteinase (TIMP)-4, -1 and anti-phospho-NFKBIA (p-IκB-α) inhibitor of NF-κB (IκB) protein in myocardium. Results: HE and Masson staining results showed that in the normal group, myocardial fibrosis is less, while the control group showed a large amount of fibrotic tissue (P<0.05). Tissue fibrosis in the low/high dose UDCA group and spironolactone group was significantly reduced compared with the control group (P<0.05), in which high dose of UDCA reduces fibrosis more significantly.Immunohistochemistry results showed that collagen Ⅰ and collagen Ⅲ protein expression was significantly increased (P<0.05). Whereas in the low/high UDCA dose group and spironolactone group, collagen Ⅰ and collagen Ⅲ expression were significantly decreased (P<0.05), the high UDCA dose group decreased more significantly.Western blot results suggest that TGFß-1 expression in the myocardial tissue was significantly increased compared to the normal group (P<0.05), whereas low/high UDCA dose group and spironolactone group, TGFß-1 protein expression were significantly decreased [UDCA(1.52±0.16), (1.02±0.12), (1.01±0.21)vs (2.73±0.12), P<0.05], in which high UDCA dose group TGFß-1 protein expression level decreased more significantly.However, there was no significant difference in the expression of CTGF, MMP2/9 and TIMP1/4 protein among the groups (P>0.05). UDCA decrease p-IκB-α expression and increase IκB protein expression dose-dependently. Conclusions: UDCA can relieve isoproterenol induced myocardial fibrosis and reduce the myocardial collagen Ⅰ and collagen Ⅲ deposition in a dose dependent manner.Down-regulating of TGFß-1 protein expression through the inhibition of TGR5-NF-κB signal transduction pathway might be a potential mechanism underlying UDCA's effects.

Clinical observation of umbilical cord mesenchymal stem cell treatment of severe systolic heart failure.

The aim of this study was to evaluate the effectiveness of umbilical cord mesenchymal stem cells (MSCs) in the treatment of chronic systolic heart failure. Fifty-nine hospitalized patients with heart failure were randomly divided into a treatment group (30 patients) and a control group (29 patients). The treatment group received treatment with medication as well as intracoronary transplantation of umbilical cord MSCs, and the control group, only medication. The cardiac structure, function change, and rehospitalization and mortality rates of the 2 groups were observed before and 1 and 6 months after treatment. One month after the transplantation of umbilical cord MSCs, the incidence of fatigue, chest tightness, and dyspnea was high in the treatment group. The 6-min walking distance of the treatment group was found to be significantly higher than that of the control group (P < 0.05); in addition, the NT-proBNP level, left ventricular ejection fraction, and mortality rate of the treatment group were statistically lower than those of the control group (P < 0.05). Readmission rates showed a downward trend, but the difference was not statistically significant (P > 0.05). Using umbilical cord MSCs in the treatment of congestive heart failure can help improve cardiac remodeling and cardiac function and reduce the mortality rate.

MKL1-184C>T gene polymorphism is associated with coronary artery disease in the Chinese Han population.

We investigated genetic susceptibility to coronary artery disease (CAD) by studying the association of MKL1 gene polymorphisms with CAD in the Chinese Han population. We performed a case-control study with 476 unrelated CAD patients and 325 non-CAD controls. All SNPs were genotyped with a TaqMan SNP genotyping assay. The distribution of MKL1-184C>T gene polymorphism in each group was in Hardy-Weinberg equilibrium. The frequency of the MKL1 T allele in the CAD group was significantly higher than in the control group (38.6 vs 30.8%). After logistic regression models adjusted for CAD risk factors, the risk of CAD among CT genotypes was 1.765 times higher than among the CC genotypes [odds ration (OR) = 1.765, 95% confidence interval (CI) = 1.246-2.5], and for TT genotypes it was 1.806 times higher than for the CC genotypes (OR = 1.806, 95%CI = 1.203-2.71). In summary, genotypes with at least one T allele (CT or TT genotypes) had a significantly increased CAD risk than the CC genotypes, with a ratio of 1.78 to 1 (OR = 1.780, 95%CI = 1.311-2.418). There was a close association between -184 T allele and 3VD (OR = 1.614, 95%CI = 1.259-2.07, P < 0.05). We conclude that the -184C>T of MKL1 is an important susceptibility factor for CAD in the Han Chinese in Henan Province. Homozygosity for the T allele is not only associated with an increased risk for CAD, it is also correlated with severity of stenosis in the Chinese Han population.

Identification of two novel HLA-DRB1 alleles, DRB1*0903 and DRB1*1145.

Two new HLA-DRB1 alleles were identified by sequencing-based typing in the oral submucous fibrosis and buccal cancer patients of Taiwan. They have been officially named HLA-DRB1*0903 and DRB1*1145 by the World Health Organization Nomenclature Committee. The complete exon 2 sequence of DRB1*0903 was identical to that of the DRB1*090102 but differed by nucleotides of position 207-210 and 216 (AGAC, C replacing GCGG, and G). The DRB1*1145 was identical to the DRB1*110101 except for three nucleotide substitutions at codon 199, 220, and 221 (A, CT replacing T, and GC). Two complete exon 2 sequences of those new alleles had been deposited in the EMBL Sequence Database under accession number AY465114 and AY465115, respectively.