Xinhua Qu

Magnesium and the Risk of Cardiovascular Events: A Meta-Analysis of Prospective Cohort Studies

Background Prospective studies that have examined the association between dietary magnesium intake and serum magnesium concentrations and the risk of cardiovascular disease (CVD) events have reported conflicting findings. We undertook a meta-analysis to evaluate the association between dietary magnesium intake and serum magnesium concentrations and the risk of total CVD events. Methodology/Principal Findings We performed systematic searches on MEDLINE, EMBASE, and OVID up to February 1, 2012 without limits. Categorical, linear, and nonlinear, dose-response, heterogeneity, publication bias, subgroup, and meta-regression analysis were performed. The analysis included 532,979 participants from 19 studies (11 studies on dietary magnesium intake, 6 studies on serum magnesium concentrations, and 2 studies on both) with 19,926 CVD events. The pooled relative risks of total CVD events for the highest vs. lowest category of dietary magnesium intake and serum magnesium concentrations were 0.85 (95% confidence interval 0.78 to 0.92) and 0.77 (0.66 to 0.87), respectively. In linear dose-response analysis, only serum magnesium concentrations ranging from 1.44 to 1.8 mEq/L were significantly associated with total CVD events risk (0.91, 0.85 to 0.97) per 0.1 mEq/L (Pnonlinearity = 0.465). However, significant inverse associations emerged in nonlinear models for dietary magnesium intake (Pnonlinearity = 0.024). The greatest risk reduction occurred when intake increased from 150 to 400 mg/d. There was no evidence of publication bias. Conclusions/Significance There is a statistically significant nonlinear inverse association between dietary magnesium intake and total CVD events risk. Serum magnesium concentrations are linearly and inversely associated with the risk of total CVD events.

A meta-analysis of 18FDG-PET–CT, 18FDG-PET, MRI and bone scintigraphy for diagnosis of bone metastases in patients with lung cancer

BACKGROUND AND PURPOSE Lung cancer is the most common cause of cancer related death among both men and women worldwide. The skeleton is the most common site of cancer metastasis. Early detection is crucial for prognosis. To evaluate and compare the capability for bone metastasis assessment of [(18)F] fluoro-2-d-glucose positron emission tomography with computed tomography ((18)FDG-PET-CT), [(18)F] fluoro-2-d-glucose positron emission tomography ((18)FDG-PET), magnetic resonance imaging (MRI) and bone scintigraphy (BS) in lung cancer patients, a meta-analysis is preformed. METHODS We searched MEDLINE, OVID, EMBASE and the Cochrane Library for studies evaluating diagnosis validity of (18)FDG-PET-CT, (18)FDG-PET, MRI and BS between January 1990 and August 2010. Meta-analysis methods were used to pool sensitivity, specificity, diagnostic odd ratios (DORs) and to construct a summary receiver-operating characteristic curve (SROC). RESULTS A total of 17 articles (9 (18)FDG-PET-CT studies, 9 (18)FDG-PET studies, 6 MRI studies and 16 BS studies) that included 2940 patients who fulfilled all of the inclusion criteria were considered for inclusion in the analysis. The pooled sensitivity for the detection of bone metastasis in lung cancer using (18)FDG-PET-CT, (18)FDG-PET, MRI and BS were 0.92 (95% CI, 0.88-0.95), 0.87 (95% CI, 0.81-0.92), 0.77 (95% CI, 0.65-0.87) and 0.86 (95% CI, 0.82-0.89), respectively. The pooled specificity for the detection of bone metastasis from lung cancer using (18)FDG-PET-CT, (18)FDG-PET, MRI and BS were 0.98 (95% CI, 0.97-0.98), 0.94 (95% CI, 0.92-0.96), 0.92 (95% CI, 0.88-0.95), 0.88 (95% CI, 0.86-0.89), respectively. The pooled DORs estimates for (18)FDG-PET-CT 449.17 were significantly higher than for (18)FDG-PET (118.25, P<0.001), MRI (38.27, P<0.001) and BS (63.37, P<0.001). The pooled sensitivity of BS was not correlated with the prevalence of bone metastasis. CONCLUSION The results showed that both (18)FDG-PET-CT and (18)FDG-PET were better imaging methods for diagnosing bone metastasis from lung cancer than MRI and BS. (18)FDG-PET-CT has higher diagnostic value (sensitivity, specificity and DORs) for diagnosing bone metastasis from lung cancer than any other imaging methods.

Smoking, Radiotherapy, Diabetes and Osteoporosis as Risk Factors for Dental Implant Failure: A Meta-Analysis

Background There are conflicting reports as to the association between smoking, radiotherapy, diabetes and osteoporosis and the risk of dental implant failure. We undertook a meta-analysis to evaluate the association between smoking, radiotherapy, diabetes and osteoporosis and the risk of dental implant failure. Methods A comprehensive research on MEDLINE and EMBASE, up to January 2013, was conducted to identify potential studies. References of relevant studies were also searched. Screening, data extraction and quality assessment were conducted independently and in duplicate. A random-effects meta-analysis was used to pool estimates of relative risks (RRs) with 95% confidence intervals (CIs). Results A total of 51 studies were identified in this meta-analysis, with more than 40,000 dental implants placed under risk-threatening conditions. The pooled RRs showed a direct association between smoking (n = 33; RR = 1.92; 95% CI, 1.67–2.21) and radiotherapy (n = 16; RR = 2.28; 95% CI, 1.49–3.51) and the risk of dental implant failure, whereas no inverse impact of diabetes (n = 5; RR = 0.90; 95% CI, 0.62–1.32) on the risk of dental implant failure was found. The influence of osteoporosis on the risk of dental implant failure was direct but not significant (n = 4; RR = 1.09; 95% CI, 0.79–1.52). The subgroup analysis indicated no influence of study design, geographical location, length of follow-up, sample size, or mean age of recruited patients. Conclusions Smoking and radiotherapy were associated with an increased risk of dental implant failure. The relationship between diabetes and osteoporosis and the risk of implant failure warrant further study.

The effect of metallic magnesium degradation products on osteoclast-induced osteolysis and attenuation of NF-κB and NFATc1 signaling.

Wear particle-induced aseptic prosthetic loosening is one of the most common reasons for total joint arthroplasty (TJA). Extensive bone destruction (osteolysis) by osteoclasts plays an important role in wear particle-induced peri-implant loosening. Thus, strategies for inhibiting osteoclast function may have therapeutic benefit for prosthetic loosening. Here, we mimicked the process of magnesium (Mg) degradation in vivo and obtained Mg leach liquor (MLL) by immersing pure Mg in culture medium. For the first time, we demonstrated that MLL suppresses osteoclast formation, polarization, and osteoclast bone resorption in vitro. An in vivo assay demonstrated that MLL attenuates wear particle-induced osteolysis. Furthermore, we found that MLL significantly inhibits nuclear factor-κB (NF-κB) activation by retarding inhibitor-κB degradation and subsequent NF-κB nuclear translocation. We also found that MLL attenuates the expression of NFATc1 at both the protein and mRNA levels. These results demonstrate that MLL has anti-osteoclast activity in vitro and prevents wear particle-induced osteolysis in vivo. Collectively, our study suggests that metallic magnesium, one of the orthopedic implants with superior properties, has significant potential for the treatment of osteolysis-related diseases caused by excessive osteoclast formation and function.

Iron deficiency anaemia can be improved after eradication of Helicobacter pylori

Background Recent guidelines on iron deficiency anaemia (IDA) have confirmed the aetiological role of Helicobacter pylori (H pylori), but the relationship still remains controversial. Methods Starting in May 2009, searches of the following databases were undertaken: Medline (1966 to April 2009), Embase (1980 to April 2009), the Cochrane library (1800 to June 2008), Cochrane Central Register of Controlled Trials, Premedline, Healthstar, CBMdisc and the Chinese National Knowledge Infrastructure Database (January 1970 to April 2009). Changes in haemoglobin (Hb) concentrations and serum ferritin (SF) concentrations were recorded for intervention and control groups. The meta-analysis used random effect models and subgroup analyses were performed to explain heterogeneity. Results Eight studies met the inclusion criteria. All studies were performed in Asia, an area with a high incidence of IDA and H pylori. The pooled analysis of eight studies showed that H pylori eradication therapy can improve IDA, since changes in Hb and SF concentrations in the intervention groups were higher than in controls. The weighted mean difference (WMD) of Hb was 12.88 g/l (95% CI 6.03 to 19.74 g/l, p<0.00001); the WMD of SF was 10.05 μg/l (95% CI 5.48 to 14.63 μg/l, p<0.00001). Conclusions H pylori eradication therapy combined with iron administration is more effective than iron administration alone for the treatment of IDA. Eradication therapy has different effects on adults and children. Bismuth based triple therapy has a better response in terms of increased Hb and SF concentrations than proton pump inhibitor (PPI) based triple therapy.

Andrographolide suppresses RANKL-induced osteoclastogenesis in vitro and prevents inflammatory bone loss in vivo.

Osteoclasts play a pivotal role in diseases such as osteoporosis, rheumatoid arthritis and tumour bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast‐related diseases. Here, we examined changes in osteoclastogenesis and LPS‐induced osteolysis in response to andrographolide (AP), a diterpenoid lactone isolated from the traditional Chinese and Indian medicinal plant Andrographis paniculata.

Meta-Analysis of Sonication Fluid Samples from Prosthetic Components for Diagnosis of Infection after Total Joint Arthroplasty

ABSTRACT This meta-analysis included 12 studies that evaluated sonication fluid cultures (SFC) for the diagnosis of prosthetic joint infection (PJI). The pooled sensitivity and specificity were 0.80 (95% confidence interval [CI], 0.74 to 0.84) and 0.95 (CI, 0.90 to 0.98), respectively. Subgroup analyses showed that a 14-day anaerobic culture may improve sensitivity, the use of centrifugation or vortexing may improve specificity, and the use of 400 to 500 ml of Ringers solution for containers may improve sensitivity and specificity. The best SFC cutoff was ≥5 CFU. In conclusion, SFC has high sensitivity and very high specificity for diagnosing PJI.

The accuracy of ultrasonography in the preoperative diagnosis of cervical lymph node metastasis in patients with papillary thyroid carcinoma: A meta-analysis

BACKGROUND Ultrasonography has been proposed to enhance preoperative assessment of cervical lymph node status in patients with papillary thyroid carcinoma (PTC). Management is most controversial for patients with a clinically negative (cN0) neck. We aimed to evaluate the diagnostic properties of ultrasonography in the detection of cervical lymph node metastasis in patients with PTC. MATERIALS AND METHODS Studies evaluating the diagnostic accuracy of Ultrasonography in the diagnosis of cervical lymph node metastasis in patients with PTC were systematically searched for in the MEDLINE, EMBASE, Cancerlit and Cochrane Library and other database from January 1995 to November 2010. Two reviewers independently abstracted data including research design, sample size, imaging technique and technical characteristics, method of image interpretation. By patient-based and region- or node-based data analyses, we determined pooled sensitivities and specificities across studies, and constructed summary receiver operating characteristic curves, and area under summary receiver operating characteristic curves were calculated. RESULTS The pooled patient-based sensitivity for ultrasonography was 0.72 (95% CI, 0.46-0.88), specificity was 0.98 (95% CI, 0.84-1.00), and the area under the curve (AUC) was 0.94 (95% CI, 0.92-0.0.96). The pooled region- or node-based sensitivity for ultrasonography was 0.63 (95% CI, 0.47-0.76), specificity was 0.93 (95% CI, 0.73-0.99), and the AUC was 0.81 (95% CI, 0.77-0.84). For lesion-based analysis, the subgroup of lateral compartment lymph node involvement was found to have the highest sensitivity (0.72, 95% CI 0.68-0.75) and specificity (0.97, 95% CI 0.93-0.99) among the studies (p<0.05). Study sensitivity was not correlated with the prevalence of cervical lymph node metastasis (patient-based: R(2)=0.0196, p=0.7915; region- or node-based: R(2)=0.3835, p=0.1381). CONCLUSIONS We conclude that preoperative ultrasonography is a good technique for the preoperative lymph node staging of PTC and is helpful for detecting metastatic cervical lymph nodes at the lateral group. High-quality prospective studies regarding ultrasonography in the evaluation of cervical lymph node status in patients with PTC are still needed to be conducted.

MicroRNAs play a role in chondrogenesis and osteoarthritis (Review)

Osteoarthritis (OA) is one of the most widespread degenerative joint diseases affecting the elderly. Research into the regulatory mechanisms underlying the pathogenesis of OA is therefore warranted, and over the past decade, there has been an increased focus on the functional role of microRNAs (miRNAs or miRs). In this systematic review, we aimed to review the evidence implicating miRNAs in the pathogenesis of chondrogenesis and OA. Systematic reviews of PubMed and Embase were performed to search for studies using strings of miRNAs, non-coding RNAs, cartilage, chondrocytes, chondrogenesis, chondrocytogenesis and OA. The identified studies were retrieved, and the references provided were searched. The selected studies were required to focus on the role of miRNAs in chondrogenesis and OA. The results of this review indicated that more than 25 miRNAs have been implicated in chondrogenesis and OA. In particular, chondrocytogenesis, chondrogenic differentiation, chondrocyte proliferation, chondrocyte hypertrophy, endochondral ossification, and proteolytic enzyme regulation are targeted or facilitated by more than 1 miRNA. To date, limited efforts have been performed to evaluate translational applications for this knowledge. Novel therapeutic strategies have been developed and are under investigation to selectively modulate miRNAs, which could potentially enable personalized OA therapy. miRNAs appear to be important modulators of chondrogenesis and OA. Their expression is frequently altered in OA, and many are functionally implicated in the pathogenesis of the disease. The translational roles and therapeutic potential of miRNAs remains to be evaluated.

PCR-Based Diagnosis of Prosthetic Joint Infection

ABSTRACT We performed a meta-analysis to evaluate use of PCR assays for diagnosis of prosthetic joint infection (PJI). The pooled sensitivity and specificity were 0.86 (95% confidence interval [CI], 0.77 to 0.92) and 0.91 (CI, 0.81 to 0.96), respectively. Subgroup analyses showed that use of tissue samples may improve sensitivity, and quantitative PCR and sonication of prostheses fluid may improve specificity. The results showed that PCR is reliable and accurate for detection of PJI.