The influence of connective tissue growth factor on rabbit ligament injury repair

Objectives

The injured anterior cruciate ligament (ACL) is thought to exhibit an impaired healing response, and attempts at surgical repair have not been successful. Connective tissue growth factor (CTGF) is reported to be associated with wound healing, probably through transforming growth factor beta 1 (TGF-β1).

Methods

A rabbit ACL injury model was used to study the effect of CTGF on ligament recovery. Quantitative real-time PCR (qRT-PCR) was performed for detection of changes in RNA levels of TGF-β1, type 1 collagen (COL1), type 2 collagen (COL2), SRY-related high mobility group-box gene9 (SOX9), tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metallopeptidase 13 (MMP-13). Expression of related proteins was detected by Western blotting.

Results

The current study showed that CTGF could promote the recovery of an injured anterior cruciate ligament. It can upregulate mRNA and expression of TGF-β1, COL1, COL2, SOX9, and tissue inhibitor of TIMP-1, and downregulate mRNA and expression of MMP-13, suggesting that the curative effect of CTGF on injured rabbit ligaments is through regulation of these cellular factors.

Conclusions

This finding revealed the healing role of CTGF in injured tissues and provides new possibilities of treating injured tissues and wound healing by using CTGF.

Cite this article: X. Sun, W. Liu, G. Cheng, X. Qu, H. Bi, Z. Cao, Q. Yu. The influence of connective tissue growth factor on rabbit ligament injury repair. Bone Joint Res 2017;6:399–404. DOI: 10.1302/2046-3758.67.BJR.2016-0255.R1.

The associations between serum 25-hydroxyvitamin D level and the risk of total fracture and hip fracture

In this meta-analysis, we evaluated the association between serum 25-hydroxyvitamin D (25(OH) vitamin D) level and the risk of total fractures and hip fractures. Low serum 25(OH) vitamin D level is associated with an increased risk of total and hip fractures.

INTRODUCTION

Data on the association between serum 25(OH) vitamin D level and the risk of fractures are conflicting. This study aimed to provide a summary of prospective cohort or nested case-control studies on the association between serum 25(OH) vitamin D level and the risk of total fractures and hip fractures.

METHODS

We identified relevant studies by searching the PubMed, EMBASE, and OVID databases from their inception to June 1, 2016. We included published prospective cohort or nested case-control studies evaluating the associations of serum 25(OH) vitamin D level with the fracture risk. Two reviewers abstracted the data independently. Relative risks (RRs) with 95% confidence intervals (CIs) were derived throughout the whole analysis.

RESULTS

Sixteen prospective cohort studies and three nested case-control studies were included. We found that low serum 25(OH) vitamin D level was significantly associated with the risk of total fractures (RR 1.25, 95% CI 1.06-1.43; I ² = 31.3%, p for heterogeneity = 0.15) and hip fractures (RR 1.48, 95% CI 1.29-1.68; I ² = 0%, p for heterogeneity = 0.51). The hip fracture risk was increased by 40% for each SD decrease in serum 25(OH) vitamin D level (RR 1.40, 95% CI 1.20-1.61; I ² = 0%, p for heterogeneity = 0.51). The per SD decrease in serum 25(OH) vitamin D level was not associated with the increased risk of total fractures (RR 1.14, 95% CI 0.93-1.35; I ² = 63.2%, p for heterogeneity = 0.04).

CONCLUSIONS

Our study suggests that low serum 25(OH) vitamin D level is associated with increased risks of total and hip fractures. In the analyzed studies, the per SD decrease in serum 25(OH) vitamin D level was associated with the hip fracture risk but not with the total fracture risk.

Proton pump inhibitor monotherapy and the risk of cardiovascular events in patients with gastro-esophageal reflux disease: a meta-analysis

BACKGROUND AND PURPOSE

Proton pump inhibitors (PPIs) are commonly used as potent gastric acid secretion antagonists for gastro-esophageal disorders and their overall safety in patients with gastro-esophageal reflux disease (GERD) is considered to be good and they are well-tolerated. However, recent studies have suggested that PPIs may be a potential independent risk factor for cardiovascular adverse events. The aim of our meta-analysis was to examine the association between PPI monotherapy and cardiovascular events in patients with GERD.

METHODS

A literature search involved examination of relevant databases up to July 2015 including PubMed, Cochrane Library, EMBASE, and ClinicalTrial.gov, as well as selected randomized controlled trials (RCTs) reporting cardiovascular events with PPI exposure in GERD patients. In addition, the pooled risk ratio (RR) and heterogeneity were assessed based on a fixed effects model of the meta-analysis and the I² statistic, respectively.

KEY RESULTS

Seventeen RCTs covering 7540 patients were selected. The pooled data suggested that the use of PPIs was associated with a 70% increased cardiovascular risk (RR=1.70, 95% CI: [1.13-2.56], P=.01, I² =0%). Furthermore, higher risks of adverse cardiovascular events in the omeprazole subgroup (RR=3.17, 95% CI: [1.43-7.03], P=.004, I² =25%) and long-term treatment subgroup (RR=2.33, 95% CI: [1.33-4.08], P=.003, I² =0%) were found.

CONCLUSION & INFERENCES

PPI monotherapy can be a risk factor for cardiovascular adverse events. Omeprazole could significantly increase the risk of cardiovascular events and, so, should be used carefully.

Efficacy of statins for osteoporosis: a systematic review and meta-analysis

Our meta-analysis assessed the efficacy of statins on the risk of fracture, bone mineral density (BMD), and the markers of bone metabolism by collecting data from 33 clinical trials. We found that statin treatment was associated with bone metabolism. And statins seemed to be more effective on male patients with osteoporosis. The efficacy of statins for the treatment of osteoporosis has been controversial in previous studies and meta-analyses. Our meta-analysis was conducted to examine in detail the efficacy of statins on osteoporosis. We searched PubMed, Embase, and the Cochrane Library databases for clinical trials from inception to May 2016. We included studies that described the effect of statins on the risk of fracture, BMD, or bone turnover markers. Moreover, we also conducted subgroup analyses according to the skeleton site, patient gender, and length of follow-up. A total of 33 studies which included 23 observational studies (16 cohort studies and 7 case-control studies) and 10 randomized controlled trials (RCTs) were evaluated. These 33 studies included 314,473 patients in statin group and 1,349,192 patients in control group. Statins decreased the risk of overall fractures (OR = 0.81, 95% CI 0.73-0.89) and hip fractures (OR = 0.75, 95% CI 0.60-0.92). Furthermore, the use of statins was associated with increased BMD at the total hip (standardized mean difference (SMD) = 0.18, 95% CI 0.00-0.36) and lumbar spine (SMD = 0.20, 95% CI 0.07-0.32) and improved the bone formation marker, osteocalcin (OC) (SMD = 0.21, 95% CI 0.00-0.42). However, there was no positive effect on vertebral fractures, upper extremity fractures, BMD at the femoral neck, bone-specific alkaline phosphatase (BALP), and serum C-terminal peptide of type I collagen (S-CTX). Also, compared with male subgroups, the effect on female subgroups was only slightly positive or of no statistical significance. Our meta-analysis indicates that statin treatment may be associated with a decreased risk of overall fractures and hip fractures, an increased BMD at the total hip, BMD at the lumbar spine, and OC. Moreover, our results also show that statin treatment may have a greater effect on male patients than on female patients.

Loss of p300 accelerates MDS-associated leukemogenesis

The role that changes in DNA methylation and histone modifications have in human malignancies is poorly understood. p300 and CREB-binding protein (CBP), two distinct but highly homologous lysine acetyltransferases, are mutated in several cancers, suggesting their role as tumor suppressors. In the current study, we found that deletion of p300, but not CBP, markedly accelerated the leukemogenesis ofNup98-HoxD13 (NHD13) transgenic mice, an animal model that phenotypically copies human myelodysplastic syndrome (MDS). p300 deletion restored the ability of NHD13 expressing hematopoietic stem and progenitor cells (HSPCs) to self-renew in vitro, and to expand in vivo, with an increase in stem cell symmetric self-renewal divisions and a decrease in apoptosis. Furthermore, loss of p300, but not CBP, promoted cytokine signaling, including enhanced activation of the MAPK and JAK/STAT pathways in the HSPC compartment. Altogether, our data indicate that p300 has a pivotal role in blocking the transformation of MDS to acute myeloid leukemia, a role distinct from that of CBP.

Different associations between blood pressure indices and carotid artery damages in a community-based population of China

Different blood pressure (BP) indices had varying associations with carotid intima-media thickness (cIMT) and plaques in clinical practice. However, insufficient evidence has focused on this issue, especially in Chinese population. Herein we examined associations of different BP indices with cIMT and plaques cross-sectionally in a community-based atherosclerosis cohort. We qualitatively measured cIMT and plaques, and also measured central systolic blood pressure and brachial systolic blood pressure (baSBP), from which pulse pressure (PP), and second PP (PP2) were calculated. Logistic multivariate regression was used to assess the associations with BP indices and carotid artery hypertrophy (increased cIMT) and the extent of atherosclerosis (presence of plaques). Each BP index was significantly and independently associated with increased cIMT and plaques except the association of baSBP with plaques. When every two BP indices were put into one model, brachial pressure indices were associated with increased cIMT independently of central pressures, whereas the association between central pressure indices and plaque presence were stronger than those of brachial pressures. In addition, SBP indices were associated with increased cIMT independently of PP indices, whereas PP indices were more strongly related to plaques. In conclusion, central and PP indices might be associated with plaques; however, brachial and SBP indices might be associated with increased cIMT. Nevertheless, whether these BP indices predict increased cIMT and plaque progression warrants further longitudinal and laboratory studies.

Note: Application of a novel 2(3HUS+S) parallel manipulator for simulation of hip joint motion

In the paper, a novel 2(3HUS+S) parallel manipulator, which has two moving platforms, is proposed. The parallel manipulator is adopted to simulate hip joint motion and can conduct an experiment for two hip joints simultaneously. Motion experiments are conducted in the paper, and the recommended hip joint motion curves from ISO14242 and actual hip joint motions during jogging and walking are selected as the simulated motions. The experimental results indicate that the 2(3HUS+S) parallel manipulator can realize the simulation of many kinds of hip joint motions without changing the structure size.

Graphene-clad microfibre saturable absorber for ultrafast fibre lasers

Graphene, whose absorbance is approximately independent of wavelength, allows broadband light–matter interactions with ultrafast responses. The interband optical absorption of graphene can be saturated readily under strong excitation, thereby enabling scientists to exploit the photonic properties of graphene to realize ultrafast lasers. The evanescent field interaction scheme of the propagating light with graphene covered on a D-shaped fibre or microfibre has been employed extensively because of the nonblocking configuration. Obviously, most of the fibre surface is unused in these techniques. Here, we exploit a graphene-clad microfibre (GCM) saturable absorber in a mode-locked fibre laser for the generation of ultrafast pulses. The proposed all-surface technique can guarantee a higher efficiency of light–graphene interactions than the aforementioned techniques. Our GCM-based saturable absorber can generate ultrafast optical pulses within 1.5 μm. This saturable absorber is compatible with current fibre lasers and has many merits such as low saturation intensities, ultrafast recovery times, and wide wavelength ranges. The proposed saturable absorber will pave the way for graphene-based wideband photonics.

A multiplexed immunoaggregation biomarker assay using a two-stage micro resistive pulse sensor

We present an immunoaggregation assay chip for multiplexed biomarkers detection. This chip is based on immunoaggregation of antibody functionalized microparticles (Ab-MPs) to quantify concentrations of multiple biomarkers simultaneously. A mixture of multiple types of Ab-MPs probes with different sizes and magnetic properties, which were functionalized by different antibodies, was used for the multiplexed assay. The interactions between biomarkers and their specific Ab-MPs probes caused the immunoaggregation of Ab-MPs. A two-stage micro resistive pulse sensor was used to differentiate and count the Ab-MP aggregates triggered by different biomarkers via size and magnetic property for multiplexed detection. The volume fraction of each type of Ab-MP aggregates indicates the concentration of the corresponding target biomarker. In our study, we demonstrated multiplexed detection of two model biomarkers (human ferritin and mouse anti-rabbit IgG) in 10% fetal bovine serum, using anti-ferritin Ab and anti-mouse IgG Ab functionalized MPs. We found that the volume fraction of Ab-MP aggregates increased with the increased biomarker concentrations. The detection ranges from 5.2 ng/ml to 208 ng/ml and 3.1 ng/ml to 5.12 × 10(4 )ng/ml were achieved for human ferritin and mouse anti-rabbit IgG. This bioassay chip is able to quantitatively detect multiple biomarkers in a single test without fluorescence or enzymatic labeling process and hence is promising to serve as a useful tool for rapid detection of multiple biomarkers in biomedical research and clinical applications.

Phase diagram of the Nd2Fe14B–Sm2Fe14B pseudo-binary system

The phase relations in the (1−x)Nd2Fe14B–xSm2Fe14B system over the whole concentration range have been studied by means of X-ray powder diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Crystal structure parameters for all studied compositions of (Nd1−xSmx)2Fe14B have been determined by full-profile Rietveld refinements. These results revealed that all intermediate alloys of (Nd1−xSmx)2Fe14B are similar to the end member of the investigated system, Nd2Fe14B, with a tetragonal structure (space groupP42/mnm). The formation of continuous solid solutions has been found in this system. The normalized lattice parameters and unit-cell volumes of (Nd1−xSmx)2Fe14B solid solutions decrease linearly with increasing Sm content. The DTA measurements show that the melting temperature of (Nd1−xSmx)2Fe14B increases linearly with increasing Sm content and no metastable phases were detected. Based on the DTA data and XRD results, a tentative phase diagram for the pseudo-binary system Nd2Fe14B–Sm2Fe14B has been constructed.