Evaluation of the relationship and genetic overlap between Kashin-Beck disease and body mass index

OBJECTIVES

Body mass index (BMI) is one of the major factors affecting the development of osteoarthritis (OA) but there is currently no information available regarding the relationship between BMI and Kashin-Beck disease (KBD). Our aim in this study was to investigate the relationship and genetic overlap between BMI and KBD.

METHOD

A total of 2050 Han Chinese subjects participated in this study. Using a cohort of 333 grade I KBD patients, logistic regression analysis was conducted to evaluate the correlation between BMI and KBD. Another independent sample of 1717 subjects was genotyped for a genome-wide association study (GWAS) using Affymetrix Human SNP 6.0 Arrays. Single nucleotide polymorphism (SNP) effect concordance analysis (SECA) was applied to the GWAS summaries of KBD and BMI for pleiotropy analysis. Genome-wide bivariate association analysis (GWBAA) of KBD and BMI was carried out to identify the genes with pleiotropic effects on KBD and BMI. The relevance of identified genes with KBD was validated by gene expression profiling and immunohistochemistry.

RESULTS

BMI correlated positively with knee movement disorder in KBD (coefficient β = 0.068, p = 0.045). SECA identified a significant pleiotropic effect (empirical p = 0.021) between KBD and BMI. In the GWBAA, the rs1893577 of the ADAMTS1 gene achieved the most significant association signal (p = 7.38 × 10^-9). ADAMTS1 was also up-regulated in KBD vs. normal (ratio = 2.64 ± 2.80) and KBD vs. OA (ratio = 2.31 ± 2.01). The rate of ADAMTS1-positive chondrocytes in KBD was significantly higher than that in OA (p < 0.05) and healthy controls (p < 0.05).

CONCLUSIONS

Our results suggest that ADAMTS1 is a novel susceptibility gene for KBD.

Development of New Therapeutic Agents for Fibrodysplasia Ossificans Progressiva

Fibrodysplasia ossificans progressiva (FOP, MIM #135100) is a rare genetic disorder of heterotopic endochondral ossification, resulting in transformation of soft tissue into episodic bone formation. Currently, no effective treatment for FOP has been established. The causative heterozygous genetic mutations have been identified in either the intracellular glycine-serine-rich (GS) domain or kinase domain of ALK2 (Activin-like kinase-2, also known as Activin A receptor type I, ACVR1), a type I receptor of bone morphogenetic proteins (BMP). Cumulative studies support that these mutations abnormally activate BMP signaling in a ligandindependent manner by reducing the ALK2 interaction with the negative regulator FKBP12, whereas others argue a ligand-dependent BMP signaling activation in FOP. Nevertheless, in either the ligand-independent or ligand-dependent model, ALK2 receptor activation is essential for heterotopic ossification in FOP. Thus targeting ALK2 likely represents an effective treatment for FOP. In this article, we critically review the recent progress on therapeutic strategies, with a focus on development of small molecule ALK2 inhibitors to suppress BMP signaling for FOP treatment.

Development of a high resolution plantar pressure monitoring pad based on fiber Bragg grating (FBG) sensors

BACKGROUND

High importance is given to plantar pressure monitoring in the field of biomedical engineering for the diagnosis of posture related ailments associated with diseases such as diabetes and gonarthrosis.

OBJECTIVE

This paper presents the proof-of-concept development of a new high resolution plantar pressure monitoring pad based on fiber Bragg grating (FBG) sensors.

METHODS

In the proposed configuration, the FBG sensors are embedded within layers of carbon composite material (CCM) in turn conforming to an arc shape. A total of four such arc shaped sensors are instrumented in the pad at the locations of the forefoot and the hind foot. As a test of the pad, static plantar pressure is monitored on normal subjects under various posture conditions. The pad is evaluated both as a standalone platform as well as a pad inserted inside a standard shoe.

RESULTS

An average pressure sensitivity of 1.2 pm/kPa and a resolution of approximately 0.8 kPa is obtained in this special configuration. The pad is found to be suitable in both configurations- stand-alone pad as well as an insert inside a standard shoe.

CONCLUSION

The proposed set up offers a cost-effective high resolution and accurate plantar pressure measurement system suitable for clinical deployment. The novelty of the developed pressure pad lies in its ability to be used both as platform type as well as inserted in-sole type sensor system.

Genome-wide association studies and gene expression profiles of rheumatoid arthritis: An analysis

OBJECTIVES

The molecular mechanism of rheumatoid arthritis (RA) remains elusive. We conducted a protein-protein interaction network-based integrative analysis of genome-wide association studies (GWAS) and gene expression profiles of RA.

METHODS

We first performed a dense search of RA-associated gene modules by integrating a large GWAS meta-analysis dataset (containing 5539 RA patients and 20 169 healthy controls), protein interaction network and gene expression profiles of RA synovium and peripheral blood mononuclear cells (PBMCs). Gene ontology (GO) enrichment analysis was conducted by DAVID. The protein association networks of gene modules were generated by STRING.

RESULTS

For RA synovium, the top-ranked gene module is HLA-A, containing TAP2, HLA-A, HLA-C, TAPBP and LILRB1 genes. For RA PBMCs, the top-ranked gene module is GRB7, consisting of HLA-DRB5, HLA-DRA, GRB7, CD63 and KIT genes. Functional enrichment analysis identified three significant GO terms for RA synovium, including antigen processing and presentation of peptide antigen via major histocompatibility complex class I (false discovery rate (FDR) = 4.86 × 10 - 4), antigen processing and presentation of peptide antigen (FDR = 2.33 × 10 - 3) and eukaryotic translation initiation factor 4F complex (FDR = 2.52 × 10 - 2).

CONCLUSION

This study reported several RA-associated gene modules and their functional association networks.Cite this article: X. Xiao, J. Hao, Y. Wen, W. Wang, X. Guo, F. Zhang. Genome-wide association studies and gene expression profiles of rheumatoid arthritis: an analysis. Bone Joint Res 2016;5:314-319. DOI: 10.1302/2046-3758.57.2000502.

Integrative analysis of genome-wide association studies and gene expression profiles identified candidate genes for osteoporosis in Kashin-Beck disease patients

SUMMARY

The molecular mechanism of osteoporosis (OP) in Kashin-Beck disease (KBD) patients was unclear. Our results suggest that KBD and OP shared some common causal genes, functionally involved in skeletal growth and development and chronic inflammation. Our results provide novel clues for clarifying the molecular mechanism of OP in KBD patients.

INTRODUCTION

KBD is a chronic skeletal disorder with osteopenia and OP. The pathogenesis of OP in KBD patients remains elusive.

METHODS

A total of 1717 subjects participated in this study. KBD was diagnosed according to the clinical diagnosis criteria of China (GB16395-1996). The bone mineral density (BMD) and bone areas of the ulna and radius, hip, and lumbar (L1-L4) were measured with a Hologic 4500 W dual-energy X-ray absorptiometry scanner. Genotyping was conducted using Affymetrix SNP Array 6.0. Gene expression profiling of peripheral blood mononuclear cells of KBD and OP patients were compared using Affymetrix HG-U133 plus 2.0 arrays and Agilent Human 1A arrays, respectively. Genome-wide association studies (GWAS) were conducted by PLINK. SCEA and DAVID were applied for pleiotropy and functional enrichment analysis, respectively.

RESULTS

SCEA analysis observed significant pleiotropic effects between KBD and the ulna and radius BMD (P value = 5.99 × 10(-3)). GWAS meta-analysis identified six candidate genes with pleiotropic effects, including PDGFD, SOX5, DPYD, CTR9, SPP1, and COL4A1. GO analysis identified 16 significant GO shared by KBD and the ulna and radius BMD, involved in cell morphogenesis and apoptosis. Pathway enrichment analysis detected two common pathways for KBD and the ulna and radius BMD, including calcium signaling pathway and vascular smooth muscle contraction pathway. Gene expression analysis detected three up-regulated inflammation-related genes for KBD and OP, including IL1B, IL8, and CCL1.

CONCLUSION

This study reported several candidate genes involved in the development of OP in KBD patients.

Effects of atorvastatin combined with trimetazidine on myocardial injury and inflammatory mediator in unstable angina patients during perioperative of percutaneous coronary intervention

OBJECTIVE

To investigate the effects of atorvastatin combined with trimetazidine on periprocedural myocardial injury and serum inflammatory mediators in unstable angina pectoris (UAP) patients following percutaneous coronary intervention (PCI) treatment.

PATIENTS AND METHODS

90 patients with UAP treated with conventional medications and PCI were recruited and were randomly divided into the control group and the experimental group. The control group had 42 patients were treated with atorvastatin alone, while the experimental group had 48 cases treated with atorvastatin combined with trimetazidine. All the patients were checked the preoperative 24h and postoperative 24h PCI concentrations of cardiac troponin I (cTnI), hypersensitive C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), serum interferon-γ (IFN-γ) and interlukin-10 (IL-10).

RESULTS

At the pre-PCI stage, every serum factors was no significant difference. 24 hours after the PCI intervention, the occurence of abnormal cTnI level in the experimental group was remarkable reduced than the control group. In the experimental group, the serum levels of TNF-α and IFN-γ significantly decreased (p < 0.05); while IL-10 was increased. In the control group, all the mediators were increased significantly except the hs-CRP (p < 0.05).

CONCLUSIONS

No unexpected symptom was found in patients with large dose atorvastatin combined with large dose trimetazidine. The administration of conventional medications together with the atorvastatin plus trimetazidine were able to reduce the prevalence of postoperative myocardial injury.

Combined application of FBG and PZT sensors for plantar pressure monitoring at low and high speed walking

BACKGROUND

Clinical monitoring of planar pressure is vital in several pathological conditions, such as diabetes, where excess pressure might have serious repercussions on health of the patient, even to the extent of amputation.

OBJECTIVE

The main objective of this paper is to experimentally evaluate the combined application of the Fibre Bragg Grating (FBG) and the lead zirconate titanate (PZT) piezoceramic sensors for plantar pressure monitoring during walk at low and high speeds.

METHODS

For fabrication of the pressure sensors, the FBGs are embedded within layers of carbon composite material and stacked in an arc shape. From this embedding technique, average pressure sensitivity of 1.3 pm/kPa and resolution of nearly 0.8 kPa is obtained. These sensors are found to be suitable for measuring the static and the low-speed walk generated foot pressure. Simultaneously, PZT patches of size 10 × 10 × 0.3 mm were used as sensors, utilizing the d<formula>_{33}</formula> (thickness) coupling mode. A sensitivity of 7.06 mV/kPa and a pressure resolution of 0.14 kPa is obtained from these sensors, which are found to be suitable for foot pressure measurement during high speed walking and running. Both types of sensors are attached to the underside of the sole of commercially available shoes. In the experiments, a healthy male subject walks/runs over the treadmill wearing the fabricated shoes at various speeds and the peak pressure is measured using both the sensors. Commercially available low-cost hardware is used for interrogation of the two sensor types.

RESULTS

The test results clearly show the feasibility of the FBG and the PZT sensors for measurement of plantar pressure. The PZT sensors are more accurate for measurement of pressure during walking at high speeds. The FBG sensors, on the other hand, are found to be suitable for static and quasi-dynamic (slow walking) conditions. Typically, the measured pressure varied from 400 to 600 kPa below the forefoot and 100 to 1000 kPa below the heel as the walking speed varied from 1 kilometer per hour (kmph) to 7 kmph.

CONCLUSIONS

When instrumented in combination, the two sensors can enable measurements ranging from static to high speed conditions Both the sensor types are rugged, small sized and can be easily embedded in commercial shoes and enable plantar pressure measurement in a cost-effective manner. This research is expected to have application in the treatment of patients suffering from diabetes and gonarthrosis.

The abnormal expression level of microRNA in epithelial-mesenchymal transition of peritoneal mesothelial cells induced by high glucose

OBJECTIVE

To determine the expression level of the microRNA in the process of epithelial-mesenchymal transition (EMT) of the peritoneal mesothelial cells (PMCs) induced by high glucose.

MATERIALS AND METHODS

The PMCs were cultured using M199 medium with 10% fetal bovine serum, and the EMT was induced by D-glucose stimulation. Epithelial-mesenchymal transition was determined by changes in cell morphology and the expression levels of the EMT marker genes. Changes in cell morphology were observed by inverted microscope, and the expression levels of the EMT marker genes were determined by real-time PCR. The expression levels of the microRNA were detected by real-time PCR with microRNA-specific stem-loop structure primer.

RESULTS

The PMCs changed to fusiformis following a high-glucose medium stimulated for 48 hours, and the EMT marker genes changed significantly, such as the decrease of E-cadherin and an increase of Vimentin (p < 0.01). These results proved the EMT had been induced by high-glucose. Applying real-time PCR with microRNA-specific stem-loop structure primer, miR-193a increased notably (p < 0.01), and miR-15a and let-7e decreased (p < 0.01), while miR-16 and miR-21 had no significant changes (p > 0.05). Most importantly, the increase of miR-193a was correlated with stimulus duration.

CONCLUSIONS

MicroRNA with abnormal expression levels have a primary role in regulating the EMT of PMCs induced by high glucose.

Inhibition of autophagy strengthens celastrol-induced apoptosis in human pancreatic cancer in vitro and in vivo models

OBJECTIVES

Celastrol, a quinone methide triterpenoid, could induce apoptosis in pancreatic cancer cells. The purpose of this study is to determine whether there is protective autophagy after celastrol treatment in pancreatic cancer cells and the synergistic effects of celastrol and 3-MA in vitro and in vivo.

METHODS

The cells viability was measured using MTT assays. Degree of apoptosis and amount of autophagic vacuoles were measured by flow cytometry. Immunofluorescence was adapted to monitor the localization of autophagic protein LC3-II. Expression of LC3-II, cleaved caspase-3, Bax and bcl-2 was detected by immunoblot. Autophagosomes were observed by electron microscopy. The synergistic effect of celastrol and 3- MA in vivo was studied in the MiaPaCa-2 xenograft tumor model.

RESULTS

Celastrol increased the level of autophagy in pancreatic cancer cells. Furthermore in vitro, when inhibiting the autophagy with 3-MA, the level of celastrol-induced apoptosis elevated; after upgrading autophagy by starvation, the level of celastrol-induced apoptosis descended. 3-MA enhanced celastrol-induced apoptosis and inhibitory effect on tumor growth in vivo.

CONCLUSIONS

In pancreatic cancer, celastrol treatment increased the level of autophagy to protect cancer cells against apoptosis. Autophagy inhibitor 3-MA could improve the therapeutic effect of celastrol in vitro and in vivo.

Physical activity, body mass index and mental health in Chinese adolescents: a population based study

AIM

The aim of the present study was to examine the association between physical activity, BMI level and mental health among Chinese adolescents.

METHODS

Three thousand ninety-six adolescents aged 11 to 13 were analyzed from 6 middle schools of Xuzhou. Physical activity level was measured using self-designed questionnaires. BMI was calculated according to the results of these students' physical examinations. Anxiety symptoms were assessed by using the Screen for Child Anxiety Related Emotional Disorder, depression via the Children's Depression Inventory. Data were analyzed using chi-square test and logistic regression.

RESULTS

Adolescents' self-reported rate of insufficient physical activity was 58.1%. The overweight and obesity rates were 18.4%, 16.0%. The point prevalence rates on anxiety and depression were 15.2%, 11.5%. Insufficient physical activity was positively associated with anxiety and depression (OR [95%CI]: 1.31 [1.06-1.63]; 1.33 [1.04-1.70]). Obesity was positively associated with depression (OR [95%CI]: 1.48 [1.10-2.00]). IS-OB was positively associated with anxiety and depressive (OR [95%CI]: 1.71 [1.19-2.45]; 1.99 [1.33-2.97]).

CONCLUSION

Physical inactivity and overweight/obesity were negatively association with mental health of adolescents, respectively. Meanwhile, to explore the combined effects of physical inactivity and obesity would increase the risk of anxiety and depression in adolescents.

Optimization of culture medium for anaerobic production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl for microbial enhanced oil recovery

Response surface methodology was employed to enhance the anaerobic production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl. Glycerol is a promising carbon source used to anaerobically produce rhamnolipid. In a Plackett-Burman design, glycerol, KH2 PO4 and yeast extract were significant factors. The proposed optimized medium contained the following: 46·55 g l(-1) glycerol; 3 g l(-1) NaNO3 ; 5·25 g l(-1) K2 HPO4 ·3H2 O; 5·71 g l(-1) KH2 PO4 ; 0·40 g l(-1) MgSO4 ·7H2 O; 0·13 g l(-1) CaCl2 ; 1·0 g l(-1) KCl; 1·0 g l(-1) NaCl; and 2·69 g l(-1) yeast extract. Using this optimized medium, we obtained an anaerobic yield of rhamnolipid of 3·12 ± 0·11 g l(-1) with a 0·85-fold increase. Core flooding test results also revealed that Ps. stutzeri Rhl grown in an optimized medium enhanced the oil recovery efficiency by 15·7%, which was 6·6% higher than in the initial medium. Results suggested that the optimized medium is a promising nutrient source that could effectively mobilize oil by enhancing the in situ production of rhamnolipid.

SIGNIFICANCE AND IMPACT OF THE STUDY

The ex situ application of rhamnolipid for microbial enhanced oil recovery (MEOR) is costly and complex in terms of rhamnolipid production, purification and transportation. Compared with ex situ applications, the in situ production of rhamnolipid in anaerobic oil reservoir is more advantageous for MEOR. This study is the first to report the anaerobic production optimization of rhamnolipid. Results showed that the optimized medium enhanced not only the anaerobic production of rhamnolipid but also crude oil recovery.

Low adenosine triphosphate activity in CD4+ cells predicts infection in patients with lupus nephritis

OBJECTIVES

The ImmuKnow (Cylex) assay has been reported to predict the risk of infection in some diseases; however, it is uncertain whether ImmuKnow can predict the risk of infection in lupus nephritis (LN) patients receiving immunosuppressive therapy.

METHODS

The ImmuKnow Immune Cell Function Assay (Cylex, Inc., Columbia, MD, USA) was applied to measure the activity of CD4+ T cells, as a marker of global immune-competence. The correlation between changes in T cell activation and the relative risk of over-immunosuppression as well as infection was studied. The amount of adenosine triphosphate (ATP) produced by CD4+ T cells in response to phytohemagglutinin (PHA) was measured for 74 LN patients without infection, 22 LN patients with severe infection (i.e. required hospitalisation), and 28 healthy controls.

RESULTS

No correlation was found between the ATP level and systemic lupus erythematosus (SLE) activity. The mean ATP level was significantly lower in LN patients with infection than that in healthy controls (p<0.01) and non-infected LN patients (p<0.01). The mean ATP level in non-infected LN patients was not significantly different compared to healthy controls. A cut-off ATP value of 300 ng/mL predicted infection in LN patients with a specificity of 77% and a sensitivity of 77%. Multi-variable partial correlation coefficient between the ATP assay and severe infection was r =-0.040, p<0.001; CRP was r=0.962, p<0.001.

CONCLUSIONS

The ImmuKnow assay may be effective in identifying an increased risk of infection in LN patients but is not correlated with SLE activity. Combined CRP value will increase the diagnostic rate of severe infection in SLE. Larger studies are required to establish clinical advantages of this assay in SLE treatment.