Yumiao Zhang

Genome-wide association study identifies ITPR2 as a susceptibility gene for Kashin-Beck disease in Han Chinese.

Kashin‐Beck disease (KBD) is a chronic osteochondropathy, the pathogenesis of which remains elusive. The aim of this study was to identify susceptibility genes for KBD by conducting a 2‐stage genome‐wide association study (GWAS).

Functional analyses reveal the essential role of SOX6 and RUNX2 in the communication of chondrocyte and osteoblast

SummaryThis study provides novel evidence that sex determining region Y (SRY)-box (SOX6) and runt-related transcription factor 2 (RUNX2) play essential roles in the communication of chondrocyte and osteoblast. Our findings open a new avenue to the limited understanding of the coordination effect between chondrogenesis and osteogenesis.IntroductionSox6 and Runx2 are two new susceptibility genes for osteoporosis identified by genome-wide association studies, but the functions of these genes in osteogenesis remain unclear. Both genes are essential transcription factors in chondrogenesis, which reminds us that SOX6 and RUNX2 might be involved in the coordination of chondrogenesis and osteogenesis. Therefore, this study aimed to investigate the functions of SOX6 and RUNX2 in the coupling regulation of chondrogenesis and osteogenesis.MethodsWe established a chondrogenic differentiation model of ATDC5 cell and profiled the expression of SOX6 and RUNX2 during chondroblast differentiation. We co-cultured osteoblast cells with ATDC5 cells in different differentiation stages and examined the proliferation, cell cycle progression, apoptosis, and differentiation of osteoblast cells. SOX6 or RUNX2 was knocked down using specific siRNA and the effect was examined.ResultsDuring chondrogenic differentiation, SOX6 and RUNX2 expressed sequentially in the proliferating and hypertrophic stages. Proliferative ATDC5 cells stimulated the multiplication of osteoblasts and promoted more osteoblasts to enter S-phase. Hypertrophic ATDC5 cells enhanced the differentiation of osteoblasts. Yet, the apoptosis of osteoblasts was neither affected by proliferating nor hypertrophic ATDC5 cells. Knockdown of SOX6 in proliferating ATDC5 cells significantly repressed the stimulation of osteoblast multiplication, whereas depletion of RUNX2 in hypertrophic ATDC5 cells retarded the expression of osteoblastic markers.ConclusionsOur study first reveals that SOX6 and RUNX2 play important roles in the chondrogenesis–osteogenesis coordination. This finding enriches the limited understanding about this coordination and unravels the novel function of SOX6 and RUNX2 in the endochondral ossification.

Assessment of Iron Deposition and White Matter Maturation in Infant Brains by Using Enhanced T2 Star Weighted Angiography (ESWAN): R2* versus Phase Values

Background and Purpose Iron deposition and white matter (WM) maturation are very important for brain development in infants. It has been reported that the R2* and phase values originating from the gradient-echo sequence could both reflect the iron and myelination. The aim of this study was to investigate age-related changes of R2* and phase value, and compare their performances for monitoring iron deposition and WM maturation in infant brains. Methods 56 infants were examined by enhanced T2 star weighted angiography (ESWAN) and diffusion tensor imaging in the 1.5T MRI system. The R2* and phase values were measured from the deep gray nuclei and WM. Fractional anisotropy (FA) values were measured only in the WM regions. Correlation analyses were performed to explore the relation among the two parameters (R2* and phase values) and postmenstrual age (PMA), previously published iron concentrations as well as FA values. Results We found significantly positive correlations between the R2* values and PMA in both of the gray nuclei and WM. Moreover, R2* values had a positive correlation with the iron reference concentrations in the deep gray nuclei and the FA in the WM. However, phase values only had the positive correlation with PMA and FA in the internal capsule, and no significant correlation with PMA and iron content in the deep gray nuclei. Conclusions Compared with the phase values, R2* may be a preferable method to estimate the iron deposition and WM maturation in infant brains.

Synthesis and characterisation of alumina fibres using organic/inorganic composite sol

Abstract The polyvinyl butyral–Al(NO3)3 composite sols and alumina fibres were synthesised by the sol–gel process in an aqueous solution using the polyvinyl butyral (PVB) and Al(NO3)3.9H2O (AN). The viscosity of PVB–AN composite sol increased with increasing AN content and aging time when it was laid at room temperature. The addition of AN leads to the formation of new weak peak and the deviation of diffraction angle to higher degrees according to the X-ray diffraction patterns (XRD). The exothermic peak of PVB disappeared and a weak endothermic peak was observed in differential scanning calorimetry curves of composite powders. The XRD pattern of fibres sintered at 1200°C showed the formation of α-alumina and the fibres showed smooth surface and uniform diameter.

Semi-quantitative assessment of brain maturation by conventional magnetic resonance imaging in neonates with clinically mild hypoxic-ischemic encephalopathy

Background: Mild hypoxic-ischemic encephalopathy (HIE) injury is becoming the major type in neonatal brain diseases. The aim of this study was to assess brain maturation in mild HIE neonatal brains using total maturation score (TMS) based on conventional magnetic resonance imaging (MRI). Methods: Totally, 45 neonates with clinically mild HIE and 45 matched control neonates were enrolled. Gestated age, birth weight, age after birth and postmenstrual age at magnetic resonance (MR) scan were homogenous in the two groups. According to MR findings, mild HIE neonates were divided into three subgroups: Pattern I, neonates with normal MR appearance; Pattern II, preterm neonates with abnormal MR appearance; Pattern III, full-term neonates with abnormal MR appearance. TMS and its parameters, progressive myelination (M), cortical infolding (C), involution of germinal matrix tissue (G), and glial cell migration bands (B), were employed to assess brain maturation and compare difference between HIE and control groups. Results: The mean of TMS was significantly lower in mild HIE group than it in the control group (mean ± standard deviation [SD] 11.62 ± 1.53 vs. 12.36 ± 1.26, P < 0.001). In four parameters of TMS scores, the M and C scores were significantly lower in mild HIE group. Of the three patterns of mild HIE, Pattern I (10 cases) showed no significant difference of TMS compared with control neonates, while Pattern II (22 cases), III (13 cases) all had significantly decreased TMS than control neonates (mean ± SD 10.56 ± 0.93 vs. 11.48 ± 0.55, P < 0.05; 12.59 ± 1.28 vs. 13.25 ± 1.29, P < 0.05). It was M, C, and GM scores that significantly decreased in Pattern II, while for Pattern III, only C score significantly decreased. Conclusions: The TMS system, based on conventional MRI, is an effective method to detect delayed brain maturation in clinically mild HIE. The conventional MRI can reveal the different retardations in subtle structures and development processes among the different patterns of mild HIE.

Preparation of mullite fibres by sol-gel processes using aluminium carboxylates and tetraethylorthosilicate

Abstract Mullite fibres were prepared using aluminium carboxylates (ACs) and tetraethylorthosilicate by sol–gel process. ACs were synthesised from dissolution aluminium in a mixture of formic acid and glacial acetic acid using aluminium chloride hexahydrate as catalyst. The optimum condition for obtaining ACs is as follows: the molar ratio of aluminium, formic acid and acetic acid was 1∶3∶2·26 and aluminium chloride hexahydrate was 10 wt-%. All the Al and Si components were mixed at the molecular level and linear molecules were formed in the precursor sol. The dried gel fibres completely transformed to mullite fibres at 1200°C and the calcinated fibres had a smooth surface and uniform diameter.

Genetic susceptibility of postmenopausal osteoporosis on sulfide quinone reductase-like gene

SummaryPostmenopausal osteoporosis is a major health problem with important genetic factors in postmenopausal women. We explored the relationship between SQRDL and osteoporosis in a cohort of 1006 patients and 2027 controls from Han Chinese postmenopausal women. Our evidence supported the significant role of SQRDL in the etiology of postmenopausal osteoporosis.IntroductionPostmenopausal osteoporosis (PMOP) is a metabolic bone disease leading to progressive bone loss and the deterioration of the bone microarchitecture. The sulfide-quinone reductase-like protein is an important enzyme regulating the cellular hydrogen sulfide levels, and it can regulate bone metabolism balance in postmenopausal women. In this study, we aimed to investigate whether SQRDL is associated with susceptibility to PMOP in the Han Chinese population.MethodsA total of 3033 postmenopausal women, comprised of 1006 cases and 2027 controls, were recruited in the study. Twenty-two SNPs were selected for genotyping to evaluate the association of SQRDL gene with BMD and PMOP. Association analyses in both single marker and haplotype levels were performed for PMOP. Bone mineral density (BMD) was also utilized as a quantitative phenotype in further analyses. Bioinformatics tools were applied to predict the functional consequences of targeted polymorphisms in SQRDL.ResultsThe SNP rs1044032 (P = 6.42 × 10−5, OR = 0.80) was identified as significantly associated with PMOP. Three SNPs (rs1044032, rs2028589, and rs12913151) were found to be significantly associated with BMD. Although limited functional significance can be obtained for these polymorphisms, significant hits for association with PMOP were found. Moreover, further association analyses with BMD identified three SNPs with significantly independent effects.ConclusionsOur evidence supported the significant role of SQRDL in the etiology of PMOP and suggest that it may be a genetic risk factor for BMD and osteoporosis in Han Chinese postmenopausal women.