Assessing the elastic properties of skeletal muscle and tendon using shearwave ultrasound elastography and MyotonPRO.

The purposes of this study were to compare Young's modulus values determined by shear wave ultrasound elastography (SWUE) with stiffness index obtained using a hand-held MyotonPRO device on the resting stiffness of gastrocnemius muscle belly and Achilles tendon; and to examine the test-retest reliability of those stiffness measurement using hand-held MyotonPRO. Twenty healthy volunteers participated in the study. The measurement values of muscle and tendon was determined in dominant legs. Each marker point was assessed using MyotonPRO and SWUE, respectively. Intra-operator reliability of MyotonPRO was established in 10 of the subjects. The correlation coefficients between the values of muscle and tendon stiffness indices determined by MyotonPRO and SWUE were calculated. Significant correlations were found for muscle and tendon stiffness and Young's modulus ranged from 0.463 to 0.544 (all P < 0.05). The intra-operator reliability ranged from good to excellent (ICC(3,1) = 0.787~0.928). These results suggest that the resting stiffness of gastrocnemius muscle belly and Achilles tendon measured by MyotonPRO is related to the Young's modulus of those quantified by SWUE. The MyotonPRO shows good intra-operator repeatability. Therefore, the present study shows that MyotonPRO can be used to assess mechanical properties of gastrocnemius muscle belly and Achilles tendon with a resting condition.

Assessing the viscoelastic properties of upper trapezius muscle: Intra- and inter-tester reliability and the effect of shoulder elevation.

BACKGROUND: Increasing stiffness in the upper trapezius muscle may contribute to imbalance of scapular motion, and result in shoulder and neck discomfort during shoulder flexion. Therefore, it is essential to quantify upper trapezius stiffness in various shoulder positions in order to aid in the prevention of these disorders and to optimize rehabilitation. OBJECTIVES: The objectives of the present study were to examine the intra and inter-tester reliability of MyotonPRO device in measuring upper trapezius stiffness and its ability to determine changes in stiffness during shoulder flexion. METHODS: Twenty healthy male subjects (mean age: 28.3±4.8 years) were studied. The stiffness of upper trapezius was quantified using the MyotonPRO device. RESULTS: The results revealed excellent intra and inter-tester reliability for measuring upper trapezius stiffness with the shoulder in a neutral position, and also found a 14.2% increase in stiffness upon shoulder flexion between 0° and 60° of flexion. Minimal detectable change (MDC) was 26.3 N/m. CONCLUSIONS: Our findings indicate that MyotonPRO device is a feasible tool to quantify upper trapezius stiffness as well as changes in muscle stiffness. Thus, it is important to assess the changes in upper trapezius muscle stiffness due to pathology or treatments for future studies.

[Prevalence and influencing factors on psychological violence from parents to child].

OBJECTIVE: To investigate the prevalence of psychological violence against children by parents and to explore possible influencing factors. METHODS: In two primary schools from a city, located in the northeast part of China, 1 164 parents of the pupils from grade 1 to 6, were anonymously surveyed by a self-administered questionnaire, to analyze the situation of psychological violence and influencing factors. RESULTS: Of the 1 164 parents, 78.1% reported that they practised psychological violence towards their children. Compared with girls, boys were more psychologically maltreated by their parents (81.3% vs. 74.7%,P<0.01). Data from the multivariate logistic regression analysis indicated that following factors increased the risk of psychological violence against children: child being male (OR=1.684); initiated by the mother (OR=1.640), parents experiences of psychologically violent victimization (OR=2.064) during their childhood, supportive or tolerant attitudes towards corporal punishment (OR=2.618) from the parents, low awareness of the harmfulness of psychological violence against children (OR=1.666) of the parents, and lower social economic status (OR=1.745) of the family, etc. CONCLUSION: Psychological violence experienced by the parents appeared very common. Prevention programs on psychological violence should be strengthened to increase the awareness of parents on this serious problem.

Manipulation of monoubiquitin improves salt tolerance in transgenic tobacco.

Ubiquitin (Ub) is regarded as a stress protein involved in many stress responses. In this paper, sense and antisense transgenic tobacco plants, as well as the wild type and vector control, were used to study the role of Ub in salt tolerance of plants. In sense Ta-Ub2 transgenic tobacco plants, there was higher expression of Ub protein conjugates than in the wild type and vector control, but the reverse trend was observed in antisense Nt-Ub1 transgenic plants. The germination rate of tobacco seed, growth status and photosynthesis of the tobacco plants suggested that over-expressing Ub promoted the growth of transgenic tobacco plants and enhanced their salt tolerance, but the opposite effect was seen in plants with repressed Ub expression. Changes in antioxidant capacity may be one of the mechanisms underlying Ub-regulated salt tolerance. Furthermore, improved tolerance to a combination of stresses was also observed in the sense transgenic tobacco plants. These findings imply that Ub is involved in the tolerance of plants to abiotic stress.

Current status of thalassemia in minority populations in Guangxi, China.

Thalassemia is one of the most common monogenic disorders in the world. In order to develop a community-based prevention program, we screened 12,900 individuals for alpha- and beta-thalassemia in Baise City, Guangxi, China, with hematological methods and molecular assays. We found that the frequency of carriers in this area for alpha-thalassemia is 15%. Beta-thalassemia carriers comprise 4.8% of the populations. Five mutations account for 98% of alpha-thalassemia [--SEA 46.7%; -alpha/4.2, 23.9%; -alpha/3.7, 21.7%; hemoglobin (Hb) Constant Spring, 6.5%; Hb Quong Sze, 1.1%]. Seven mutations in the beta-globin gene account for 99% of the mutations [codon (CD) 41/42 (-TCTT) (39.4%), CD 17(A-->T) (32%), CD 71/72 (+A) (7.4%), -28 (A-->G) (5.8%), IVS-2-654 (C-->T) (5.8%), CD26 (Hb E) (4%), IVS-1 (G-->A) (3.7%), and CD 43(G-->T) (1.9%)]. Most individuals with alpha-thalassemia major die in the uterus or shortly after birth. Among 106 patients with beta-thalassemia major followed by our clinic, the majority died before 5 years of age. Knowledge surveys about thalassemia were conducted. Our results show a severe lack of knowledge about thalassemia in both medical professionals and in the general populations. This study shows that thalassemia is a very severe public health issue in minority populations in Baise City, China. Identification of the common mutations will allow us to design cost-effective molecular tests. There is an urgent need to educate the general population and the medical community for a successful community-based prevention program.

Cloning and characterization of the endogenous retroviral-tRNA(Glu) multigene family from human genomes of different racial backgrounds.

An 8.3-kb human endogenous retroviral-tRNA(Glu) (HERV-E)-encoding cDNA clone and a 1.5-kb genomic clone were isolated from a Chinese-derived cervical cancer cell line, CC7T, and their sequences determined. The former is a full-length endogenous retroviral cDNA containing corresponding u5-gag-pol-env-u3-r regions. The latter is a partial retroviral DNA segment, covering the gag and pol genes. Analysis of normal human DNA by Southern blot hybridization with three specific HERV-E molecular DNA probes revealed complex restriction-fragment length polymorphisms (RFLP), implying that the human genome contains diverse proviral structures and dispersed integration sites. The complex patterns were virtually identical between DNAs from African-Americans, Asians and Caucasians, with only a few minor variations. The data suggest that these proviral sequences were mostly incorporated into the human genome before racial divergence and, hence, may serve as markers for distinct chromosomal sites.