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.

Mucosa-associated microbiota signature in colorectal cancer

The aim of this study was to explore the gut microbiota profiles of colorectal cancer (CRC) patients and to examine the relationship between gut microbiota and other key molecular factors involved in CRC tumorigenesis. In this study, a 16S rDNA sequencing platform was used to identify possible differences in the microbiota signature between CRC and adjacent normal mucosal tissue. Differences in the microbiota composition in different anatomical colorectal tumor sites and their potential association with KRAS mutation were also explored. In this study, the number of Firmicutes and Actinobacteria decreased, while the number of Fusobacteria increased in the gut of CRC patients. In addition, at the genus level, Fusobacterium was identified as the key contributor to CRC tumorigenesis. In addition, a different distribution of gut microbiota in ascending and descending colon cancer samples was observed. Lipopolysaccharide biosynthesis-associated microbial genes were enriched in tumor tissues. Our study suggests that specific mucosa-associated microbiota signature and function are significantly changed in the gut of CRC patients, which may provide insight into the progression of CRC. These findings could also be of value in the creation of new prevention and treatment strategies for this type of cancer.

Characterization of retroviral infectivity and superinfection resistance during retrovirus-mediated transduction of mammalian cells

Retroviral vectors including lentiviral vectors are commonly used tools to stably express transgenes or RNA molecules in mammalian cells. Their utilities are roughly divided into two categories, stable overexpression of transgenes and RNA molecules, which requires maximal transduction efficiency, or functional selection with retrovirus (RV)-based libraries, which takes advantage of retroviral superinfection resistance. However, the dynamic features of RV-mediated transduction are not well characterized. Here, we engineered two murine stem cell virus-based retroviral vectors expressing dual fluorescence proteins and antibiotic markers, and analyzed virion production efficiency and virion stability, dynamic infectivity and superinfection resistance in different cell types, and strategies to improve transduction efficiency. We found that the highest virion production occurred between 60 and 72 h after transfection. The stability of the collected virion supernatant decreased by >60% after 3 days in storage. We found that RV infectivity varied drastically in the tested human cancer lines, while low transduction efficiency was partially overcome with increased virus titer, prolonged infection duration and/or repeated infections. Furthermore, we demonstrated that RV receptors PIT1 and PIT2 were lowly expressed in the analyzed cells, and that PIT1 and/or PIT2 overexpression significantly improved transduction efficiency in certain cell lines. Thus, our findings provide resourceful information for the optimal conditions of retroviral-mediated gene delivery.

Human β-defensin-3 induces IL-8 release and apoptosis in airway smooth muscle cells

BACKGROUND

Human airway smooth muscle cells (ASMCs) may have a pro-inflammatory role through the release of inflammatory mediators. Increasing evidence indicates that human β-defensins (HBDs) are related to pathogenesis of asthma.

OBJECTIVES

To examine the plasma level of HBD-1, HBD-2 and HBD-3 in asthmatic patients and the expression of their mouse orthologues in the lung tissue of a mouse model of chronic severe asthma. Further to investigate the effect of HBD-3 on the release of the pro-inflammatory cytokine IL-8 and to explore the mechanisms.

METHODS

The plasma levels of HBD-1, HBD-2 and HBD-3 from 34 healthy controls and 25 asthmatic patients were determined by ELISA. The expression of mouse β-defensins MBD-1, MBD-3 and MBD-14 in the lung tissue of asthmatic mice was detected by Western blot. The ASMCs were cultured with HBD-3 for 24 hour, and then the supernatant level of IL-8 was evaluated by ELISA and the cell viability was examined by WST-1 assay. The signalling pathway was investigated with blocking antibodies or pharmacological inhibitors.

RESULTS

The plasma levels of HBD-1 and HBD-3 were elevated in asthmatic patients, and the expression of MBD-14, the mouse orthologue for HBD-3, was increased in asthmatic mice. HBD-3-induced IL-8 production in a CCR6 receptor-specific manner and was dependent on multiple signalling pathways. Moreover, HBD-3-induced cell apoptosis concurrently, which was dependent on the ERK1/2 MAPK pathway. Mitochondrial ROS regulated both HBD-3-induced IL-8 production and cell apoptosis.

CONCLUSIONS AND CLINICAL RELEVANCE

These observations provide clear evidence of an important new mechanism for the promotion of airway inflammation and tissue remodelling with potential relevance for the treatment of asthma.

Postnatal alteration of monocarboxylate transporter 1 expression in the rat corpus callosum

In the central nervous system (CNS), monocarboxylate transporter 1 (MCT1) is expressed in astrocytes and endothelial cells but also in oligodendroglia. Oligodendroglia support neurons and axons through lactate transportation by MCT1. Limited information is available on the MCT1 expression changes in candidate cells in the developing rat brain, especially in corpus callosum which is the most vulnerable area in demyelinating diseases. In the present study, we investigated the expression pattern of MCT1 during postnatal development in the rat corpus callosum using immunofluorescene staining, Western blotting analysis and RT-PCR. We reported that MCT1 gene and protein were consistently expressed in the rat corpus callosum from birth to adult. MCT1/CNPase and MCT1/GFAP immunofluorescence staining demonstrated that most of MCT1 positive cells were co-labeled with cyclic nucleotide 3´ phosphodiesterase (CNPase) in rat corpus callosum from P7 to adult, whereas MCT1(+)/GFAP(+) cells preserve the dominate position before P7. Moreover, there were significant associations between the expression of MCT1 protein and the expression of myelin basic protein (MBP) (correlation coefficient: r=0.962, P=0.009) from P7 to adult. Similarly, the MCT1 mRNA expression was also significantly associated with MBP mRNA expression (r=0.976, P=0.005). Our results are proposing that in the developing brain white matter, MCT1 is predominately expressed in oligodendrocyte though it mainly expressed in astrocyte in early postnatal, which indicate that MCT1 may involve in the oligodendrocyte development and myelination.

The influence of delipidation on triglyceride and LIPIN1 of porcine embryos derived from parthenogenetic activation

Proteins in the LIPIN family play key roles in lipid synthesis mainly on triacylglycerol (TAG) biosynthesis, and they also act as transcriptional coactivators to regulate the expression of genes involved in lipid metabolism with other nuclear factors. Hence, this study was designed to investigate LIPIN1 in pig oocytes and embryos by the delipidation. After delipidation, the content of lipids (LDs) and TAG in MII oocyte was significantly reduced; however, a similar increasing tendency of TAG was shown during embryos development. Subsequently, the expression of genes related to TAG biosynthesis including GPAT1, AGPAT1, AGPAT2, LIPIN1, DGAT and the nuclear factors interacted with LIPIN1 including PPARα and PPARγ was investigated. It is obvious that DGAT and GPAT1, and LIPIN1 increased significantly after delipidation at 1-cell and 4-cell stage, and the expression of PPARα and PPARγ also increased at 4-cell stage. By immunofluorescence staining and Western blots, LIPIN1 was found to exhibit a dynamic localization pattern and gradually increase with the development of delipated embryo. In the early developmental stages (1-, 2- and 4-cell stages), it was distributed over the cortical layer. But at the blastocyst stage, a homogeneous distribution of LIPIN1 was observed in cytoplasm. At 2-cell stage, the expression of PPARα decreased when LIPIN1 was interfered by small interfering RNA, but PPARγ has no significant difference. Therefore, in this study, we find after delipidation, the content of TAG and LIPIN1 will gradually increase during embryo development and nuclear factor PPARα and PPARγ can also be affected by delipidation. The interaction of LIPIN1 and PPARα exists in porcine embryo.

MiR-384 Regulates the Th17/Treg Ratio during Experimental Autoimmune Encephalomyelitis Pathogenesis

Specific miRNAs are involved in the pathogenesis of multiple sclerosis (MS), during which IL-17-producing CD4⁺ T helper (Th17) cells accumulate in the central nervous system (CNS). In this study, we identified levels of miR-384 as significantly increased in mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Over-expression of miR-384 in vivo led to severe EAE, characterized by exacerbated demyelination, and increased inflammatory cell infiltration of the spinal cord; inhibition of miR-384 reversed these changes. Both the percentage of Th17, and ratio of Th17/regulatory T (Treg), cells were elevated in miR-384-transfected EAE mice, which was consistent with the observed upregulation of expression of IL-17 and the Th17 lineage-specific transcription factor, RORγt. Importantly, transfer of miR-384 overexpressing naïve T cells from wild-type (WT) to Rag1^-/- mice, which are deficient in functional autologous T and B cells, led to aggravated EAE pathogenesis, while an miR-384 inhibited group was protected from EAE. Moreover, miR-384 promoted differentiation of naïve T cells into Th17 cells in vitro. Furthermore, target prediction and dual luciferase reporter assays demonstrated that suppressor of cytokine signaling 3 (SOCS3), a gene encoding protein with an established role in Th17 differentiation, was a direct target of miR-384. Our results demonstrate an important role for miR-384 in regulation of the Th17/Treg ratio during the pathogenesis of EAE, indicating that this molecule may have potential as a biomarker and/or therapeutic target in MS.

The Patterns of Practice and Outcomes of Penile Cancer in Ontario

AIMS

Penile cancer is a rare malignancy in Western countries. The management guidelines are mainly derived from retrospective studies as there are no randomised trials. The primary objective of this study was to assess patterns of practice and outcomes of penile squamous cell carcinoma in Ontario. Secondary objectives included examining trends in incidence, pathological characteristics and prognostic factors.

MATERIALS AND METHODS

All patients diagnosed with penile cancer between 2000 and 2010 were identified from the Ontario Cancer Registry and all available pathology reports related to penile cancer during this period were reviewed.

RESULTS

Pathology reports of 419 new cases of penile squamous cell carcinoma were reviewed. There was a significant improvement in completeness of the pathology reports in recent years. The age-adjusted incidence was 0.9 per 100 000 person-years. Most patients presented with a pT1 lesion (63%). A partial penectomy (40%) was the most common surgical procedure. Over 38% of patients identified to be eligible for organ-sparing surgery had a total or partial penectomy. Only 23% of the eligible patients identified to require lymph node dissection underwent the procedure. The 5 year disease-specific survival for stage 0, I, II, III were 94%, 93%, 74% and 52%, respectively.

CONCLUSIONS

There is a significant variation in the patterns of practice in Ontario. A large proportion of patients in this cohort were probably overtreated for the primary malignancy and undertreated for the regional nodes.

ARHGAP10, downregulated in ovarian cancer, suppresses tumorigenicity of ovarian cancer cells

Rho GTPase-activating proteins (RhoGAPs) are implicated in the development and progression of ovarian cancer. ARHGAP10 is a member of RhoGAP proteins and inactivates Cdc42 by converting GTP-bound form to GDP-bound form. Here, we aimed to evaluate ARHGAP10 expression profile and functions in ovarian cancer. The decreased expression of ARHGAP10 was found in 77.3% (58/75) of ovarian cancer tissues, compared with their non-tumorous counterparts. Furthermore, overall survival in ovarian cancer patients with higher expression of ARHGAP10 was longer than those with lower expression. Ectopic expression of ARHGAP10 in two ovarian cancer cell lines with lower expression of ARHGAP10 (A2780 and HO-8910) dramatically suppressed cell proliferation in vitro. In nude mice, its stable overexpression significantly inhibited the tumorigenicity of A2780 cells. We further demonstrated that overexpression of ARHGAP10 significantly inhibited cell adhesion, migration and invasion, resulted in cell arrest in G1 phase of cell cycle and a significant increase of apoptosis. Moreover, ARHGAP10 interacted with Cdc42 and overexpression of ARHGAP10 inhibited the activity of Cdc42 in A2780 cells. Gene set enrichment analysis on The Cancer Genome Atlas dataset showed that KEGG cell cycle, replication and base excision repair (BER) pathways were correlatively with the ARHGAP10 expression, which was further confirmed in ovarian cancer cells by western blotting. Hence, ARHGAP10 may serve as a tumor suppressor through inactivating Cdc42, as well as inhibiting cell cycle, replication and BER pathways. Our data suggest an important role of ARHGAP10 in the molecular etiology of cancer and implicate the potential application of ARHGAP10 in cancer therapy.

Management and outcomes of localized esophageal and gastroesophageal junction cancer in older patients

BACKGROUND

Older patients are commonly excluded from clinical trials in esophageal and gastroesophageal junction (gej) cancer. High-level evidence to guide management in this group is lacking. In the present study, we compared outcomes and described tolerance for curative- and noncurative-intent treatments among patients 70 years of age and older.

METHODS

We retrospectively reviewed all patients 70 years of age and older diagnosed with localized esophageal and gej cancer at our centre between 2005 and 2012.

RESULTS

The 74 patients identified had a median age of 77 years. Of those patients, 62% received curative-intent treatment, consisting mostly of concomitant chemoradiation therapy (n = 43, 93%). Median overall survival for patients receiving curative-intent treatment was 18.6 months [95% confidence interval (ci): 13.0 to 28.0 months], with 23% being long-term survivors (95% ci: 11.3% to 36.7%). In contrast, patients receiving noncurative-intent treatment had a median overall survival of 8.8 months (95% ci: 6.7 to 11.9 months), with none being long-term survivors (p < 0.0001). Improvement of dysphagia was seen after curative (81%) or palliative radiotherapy (78%) in symptomatic patients, and toxicities were manageable. The odds of not receiving curative treatment was higher by a factor of 8.5 among patients 80 years of age or older compared with those 70-79 years of age (95% ci: 2.5 to 28.7).

CONCLUSIONS

In managing older patients with esophageal and gej cancer, curative-intent treatment (compared with noncurative-intent treatment) leads to a significant survival benefit with a reasonable toxicity profile. Informed counselling of patients and their families about a curative treatment approach and efforts to increase awareness among oncology care providers are suggested.

Mesenchymal stem cells inhibit Th17 cells differentiation via IFN-γ-mediated SOCS3 activation

Mesenchymal stem cells (MSCs) are immunoregulatory, and the administration of them has been shown to ameliorate inflammation caused by Th17 cells. However, the mechanisms that contribute to MSC regulation on Th17 cell development are unclear. Here, we found that MSCs could inhibit Th17 cell differentiation through the activation of suppressors of cytokine signaling 3 (SOCS3) when coculture of MSCs and CD4(+)CD25(low)CD44(low)CD62L(high) T cells. Further analysis demonstrated that the inhibitory action was mediated via interferon gamma (IFN-γ), which activated signal transducer and activator of transcription-1 (STAT1) to enhance the expression of SOCS3, leading to STAT3 inhibition. Moreover, stable and reciprocal changes in H3K4me3 and H3K27me3 at the promoters of STAT1, STAT3 and RORγt determined the fate of Th17 cells. These results demonstrate that MSCs may inhibit Th17 differentiation via IFN-γ that activates SOCS3 leading to immunomodulatory effects, suggesting a possible mechanism by which MSCs could act as a cellular approach to attenuate the clinical and pathological manifestations of some autoimmune diseases.

DEC1 regulates breast cancer cell proliferation by stabilizing cyclin E protein and delays the progression of cell cycle S phase

Breast cancer that is accompanied by a high level of cyclin E expression usually exhibits poor prognosis and clinical outcome. Several factors are known to regulate the level of cyclin E during the cell cycle progression. The transcription factor DEC1 (also known as STRA13 and SHARP2) plays an important role in cell proliferation and apoptosis. Nevertheless, the mechanism of its role in cell proliferation is poorly understood. In this study, using the breast cancer cell lines MCF-7 and T47D, we showed that DEC1 could inhibit the cell cycle progression of breast cancer cells independently of its transcriptional activity. The cell cycle-dependent timing of DEC1 overexpression could affect the progression of the cell cycle through regulating the level of cyclin E protein. DEC1 stabilized cyclin E at the protein level by interacting with cyclin E. Overexpression of DEC1 repressed the interaction between cyclin E and its E3 ligase Fbw7α, consequently reducing the level of polyunbiquitinated cyclin E and increased the accumulation of non-ubiquitinated cyclin E. Furthermore, DEC1 also promoted the nuclear accumulation of Cdk2 and the formation of cyclin E/Cdk2 complex, as well as upregulating the activity of the cyclin E/Cdk2 complex, which inhibited the subsequent association of cyclin A with Cdk2. This had the effect of prolonging the S phase and suppressing the growth of breast cancers in a mouse xenograft model. These events probably constitute the essential steps in DEC1-regulated cell proliferation, thus opening up the possibility of a protein-based molecular strategy for eliminating cancer cells that manifest a high-level expression of cyclin E.

Prognostic significance of preoperative neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in patients with gallbladder carcinoma

PURPOSE

Neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) were immune response-related indicators. Preoperative NLR and PLR had been considered to be related to the prognosis of various cancers. The objective of this study was to evaluate the prognostic significance of NLR and PLR in patients with gallbladder carcinoma (GBC).

METHODS

From 2001 to 2013, 145 patients with GBC were recruited in this retrospective study. Cutoff values of NLR and PLR were determined by receiver operating characteristic curves (ROC). The correlation of clinical data, including tumor differentiation, nevin stage, TNM stage, operation margin, operation mode, NLR, PLR, hemoglobin, C reactive protein (CRP), carcinoembryonic antigen (CEA), and carbohydrate antigen 199 (CA199) with median survival period of patients was analyzed by univariate survival analysis. The multivariate prognosis analysis was performed to select the independent prognostic factors.

RESULTS

The cutoff values of NLR and PLR were 1.94 and 113.34, respectively. Compared with low NLR and low PLR group, the 5-year survival rates in high NLR and high PLR group were reduced (P < 0.05). The degree of tumor differentiation, nevin stage, TNM stage, operation mode, NLR, PLR, CA199, total bilirubin, CRP and CEA were associated with the median survival period of patients (P < 0.01). The multivariate prognosis analysis showed that NLR, nevin stage, operation mode and hemoglobin were independent prognostic factors (P < 0.05).

CONCLUSION

Preoperative NLR and PLR were closely related to prognosis of patients with GBC and might be useful for the evaluation of prognosis of patients with GBC.

Nonlinear 3D projection printing of concave hydrogel microstructures for long-term multicellular spheroid and embryoid body culture

Long-term culture and monitoring of individual multicellular spheroids and embryoid bodies (EBs) remains a challenge for in vitro cell propagation. Here, we used a continuous 3D projection printing approach - with an important modification of nonlinear exposure - to generate concave hydrogel microstructures that permit spheroid growth and long-term maintenance, without the need for spheroid transfer. Breast cancer spheroids grown to 10 d in the concave structures showed hypoxic cores and signs of necrosis using immunofluorescent and histochemical staining, key features of the tumor microenvironment in vivo. EBs consisting of induced pluripotent stem cells (iPSCs) grown on the hydrogels demonstrated narrow size distribution and undifferentiated markers at 3 d, followed by signs of differentiation by the presence of cavities and staining of the three germ layers at 10 d. These findings demonstrate a new method for long-term (e.g. beyond spheroid formation at day 2, and with media exchange) 3D cell culture that should be able to assist in cancer spheroid studies as well as embryogenesis and patient-derived disease modeling with iPSC EBs.

bFGF Protects Pre-oligodendrocytes from Oxygen/Glucose Deprivation Injury to Ameliorate Demyelination

One of the pathological hallmarks of periventricular white matter injury is the vulnerability of pre-oligodendrocytes (preOLs) to hypoxia-ischemia (HI). There is increasing evidence that basic fibroblast growth factor (bFGF) is an important signaling molecule for neurogenesis and neuroprotection in the central nervous system. However, it is unknown whether bFGF protects preOLs from oxygen/glucose deprivation (OGD) damage in vitro and promotes remyelination in HI-induced rats. In this present study, bFGF exerted a protective effect on myelin by increasing the myelin thickness, the number of myelinated axons, and myelin basic protein expression in the HI-induced demyelinated neonatal rat corpus callosum. In vitro, bFGF ameliorated the impaired mitochondria and cell processes induced by OGD to promote the survival of isolated O4-positive preOLs. Additionally, the expression of fibroblast growth factor receptor 3 (FGFR3) was dramatically up-regulated in the preOLs after bFGF administration in vivo and in vitro. Thus, bFGF-stimulated remyelination in HI-induced rats by protecting the preOLs from hypoxic injury, and the mechanism involved may be mediated by FGFR3.

The role of femoral neck anteversion in the development of osteoarthritis in dysplastic hips

There have been several studies examining the association between the morphological characteristics seen in acetabular dysplasia and the incidence of the osteoarthritis (OA). However, most studies focus mainly on acetabular morphological analysis, and few studies have scrutinised the effect of femoral morphology. In this study we enrolled 36 patients with bilateral acetabular dysplasia and early or mid-stage OA in one hip and no OA in the contralateral hip. CT scans were performed from the iliac crest to 2 cm inferior to the tibial tuberosity, and the morphological characteristics of both acetabulum and femur were studied. In addition, 200 hips in 100 healthy volunteer Chinese adults formed a control group. The results showed that the dysplastic group with OA had a significantly larger femoral neck anteversion and a significantly shorter abductor lever arm than both the dysplastic group without OA and the controls. Femoral neck anteversion had a significant negative correlation with the length of the abductor lever arm and we conclude that it may contribute to the development of OA in dysplastic hips.

An alternatively spliced heat shock transcription factor, OsHSFA2dI, functions in the heat stress-induced unfolded protein response in rice

As sessile organisms, plants have evolved a wide range of defence pathways to cope with environmental stress such as heat shock. However, the molecular mechanism of these defence pathways remains unclear in rice. In this study, we found that OsHSFA2d, a heat shock transcriptional factor, encodes two main splice variant proteins, OsHSFA2dI and OsHSFA2dII in rice. Under normal conditions, OsHSFA2dII is the dominant but transcriptionally inactive spliced form. However, when the plant suffers heat stress, OsHSFA2d is alternatively spliced into a transcriptionally active form, OsHSFA2dI, which participates in the heat stress response (HSR). Further study found that this alternative splicing was induced by heat shock rather than photoperiod. We found that OsHSFA2dI is localised to the nucleus, whereas OsHSFA2dII is localised to the nucleus and cytoplasm. Moreover, expression of the unfolded protein response (UNFOLDED PROTEIN RESPONSE) sensors, OsIRE1, OsbZIP39/OsbZIP60 and the UNFOLDED PROTEIN RESPONSE marker OsBiP1, was up-regulated. Interestingly, OsbZIP50 was also alternatively spliced under heat stress, indicating that UNFOLDED PROTEIN RESPONSE signalling pathways were activated by heat stress to re-establish cellular protein homeostasis. We further demonstrated that OsHSFA2dI participated in the unfolded protein response by regulating expression of OsBiP1.

Alcohol consumption and hip fracture risk

SUMMARY

The present meta-analysis shows that a nonlinear association between alcohol consumption and the risk of hip fracture was observed. Light alcohol consumption was inversely significantly associated with hip fracture risk, whereas heavy alcohol consumption was associated with an elevated hip fracture risk.

INTRODUCTION

Previous studies examining the association between alcohol consumption and the risk of hip fracture have reported conflicting findings. Therefore, we conducted a meta-analysis of prospective cohort studies to assess the association between alcohol consumption and the risk of hip fracture.

METHODS

PubMed and EMBASE were searched for prospective cohort studies on the relationship between alcohol consumption and the risk of hip fractures. Relative risks (RR) with 95% confidence intervals (CI) were derived using random-effects models throughout the whole analysis.

RESULTS

Eighteen prospective cohort studies were included with 3,730,424 participants and 26,168 hip fracture cases. Compared with non-drinkers, the pooled RR of hip fractures for alcohol consumption was 1.03 (95% CI, 0.91-1.15), with high heterogeneity between studies (P<0.001, I2=72.6%). A nonlinear relationship between alcohol consumption and the risk of hip fracture was identified (P nonlinearity=0.003). Compared with non-drinkers, the pooled RRs of hip fractures were 0.88 (95% CI, 0.83-0.89) for light alcohol consumption (0.01-12.5 g/day), 1.00 (95% CI, 0.85-1.14) for moderate alcohol consumption (12.6-49.9 g/day), and 1.71 (95% CI, 1.41-2.01) for heavy alcohol consumption (≥50 g/day).

CONCLUSIONS

There was no evidence of publication bias. In conclusion, a nonlinear association between alcohol consumption and the risk of hip fracture was observed in this meta-analysis. Further, light alcohol consumption was inversely significantly associated with hip fracture risk, whereas heavy alcohol consumption was associated with an elevated hip fracture risk.

Association between loop diuretic use and fracture risk

SUMMARY

Loop diuretic use has been shown to be associated with an increased fracture risk, but the findings have been inconsistent. The present meta-analysis suggests that loop diuretics show a significant positive association with the overall risk of total fractures and, specifically, hip fractures.

INTRODUCTION

Despite being widely used, there is limited, prospective randomized trial evidence regarding the skeletal effects of loop diuretics. Previous observational studies have reported conflicting findings regarding the association between loop diuretic use and the risk of fractures.

METHODS

This meta-analysis of observational studies assessed the association between loop diuretic use and the risk of fractures. The PubMed, EMBASE, and OVID databases were searched for prospective cohort and case-control studies. Relative risks (RR) with 95% confidence intervals (CI) were derived using random-effects models throughout the analysis.

RESULTS

Thirteen studies (4 cohort studies and 9 case-control studies) were included, involving 842,644 participants and 108,247 fracture cases. Compared with non-users, people who had taken loop diuretics had an approximately 15% higher risk of total fractures (95% CI, 1.04-1.26; p<0.01), with high heterogeneity between studies (I2=80.5%; p<0.01). The RR was 1.14 (95% CI, 1.08-1.19) for hip fractures and 0.99 (95% CI, 0.93-1.05) for lower arm or wrist fractures. The RR was 1.05 (95% CI, 1.00-1.11) in prospective cohort studies and 1.22 (95% CI, 1.00-1.44) in case-control studies. There was no evidence of publication bias.

CONCLUSION

The results suggest that loop diuretics show a significant positive association with the overall risk of total fractures and hip fractures.

Olig2 overexpression accelerates the differentiation of mouse embryonic stem cells into oligodendrocyte progenitor cells in vitro

Oligodendrocyte progenitor cells (OPCs) transplantation is receiving considerable attention in the field of regenerative medicine therapy for demyelinating diseases. Although embryonic stem cells (ESCs) have been successfully induced to differentiate into OPCs with cytokines cocktails in vitro, the regulatory roles of many key transcription factors in this process are not clear. Here, we introduced oligodendrocyte lineage transcription factor 2 (Olig2), a basic helix-loop-helix transcription factor, into mouse embryonic stem cells (mESCs) to investigate its effects on the differentiation of mESCs into OPCs. The results showed that Olig2 overexpression alone did not affect pluripotency of mESCs, but in the stimulation of differentiating cocktails, Olig2 accelerated mESCs to differentiate into OPCs, shortening the induction time span from normal 21 days to 11 days. Further study demonstrated the Olig2-mESCs derived OPCs were able to differentiate into C-type natriuretic peptid (CNP) and Myelin Basic Protein (MBP) positive mature oligodendrocytes (OLs) in vitro, suggesting these induced OPCs might be favorable for myelin regeneration in vivo.

Tumor resident mesenchymal stromal cells endow naïve stromal cells with tumor-promoting properties

Bone marrow mesenchymal stem/stromal cells (BM-MSCs) can infiltrate into tumors and subsequently evolve into tumor resident MSCs in tumor microenvironment. In this study, using a mouse lymphoma model, we showed that the lymphoma resident MSCs (L-MSCs) are able to confer tumor-promoting property to the naïve cocultured BM-MSCs. Examination of cytokines and chemokines showed that post exposure to L-MSCs, BM-MSCs acquired an expression profile that is similar to that in L-MSCs. In vivo, BM-MSCs educated by L-MSCs (BM-L-MSCs) possess a greatly enhanced ability in promoting lymphoma growth. Consistent with an elevated CCL-2 expression in BM-L-MSCs, the tumor-promoting effect of BM-L-MSCs largely depends on CCR2-mediated macrophage recruitment to tumor sites. We further showed that the transmission of tumor-promoting effect is partially mediated by soluble factors. Our findings thus revealed a novel reinforcing mechanism in the maintenance of tumor microenvironment.