Dietary magnesium intake and risk of metabolic syndrome: a meta-analysis

AIMS

To estimate quantitatively the association between dietary magnesium intake and risk of metabolic syndrome by combining the relevant published articles using meta-analysis.

METHODS

We reviewed the relevant literature in PubMed and EMBASE published up until August 2013 and obtained additional information through Google or a hand search of the references in relevant articles. A random-effects or fixed-effects model, as appropriate, was used to pool the effect sizes on metabolic syndrome comparing individuals with the highest dietary magnesium intake with those having the lowest intake. The dose-response relationship was assessed for every 100-mg/day increment in magnesium intake and risk of metabolic syndrome.

RESULT

Six cross-sectional studies, including a total of 24 473 individuals and 6311 cases of metabolic syndrome, were identified as eligible for the meta-analysis. A weighted inverse association was found between dietary magnesium intake and the risk of metabolic syndrome (odds ratio 0.69, 95% CI 0.59, 0.81) comparing the highest with the lowest group. For every 100-mg/day increment in magnesium intake, the overall risk of having metabolic syndrome was lowered by 17% (odds ratio 0.83, 95% CI 0. 77, 0.89).

CONCLUSION

Findings from the present meta-analysis suggest that dietary magnesium intake is inversely associated with the prevalence of metabolic syndrome. Further studies, in particular well-designed longitudinal cohort studies and randomized placebo-controlled clinical trials, are warranted to provide solid evidence and to establish causal inference.

Clinical outcome for patients with dedifferentiated chondrosarcoma: a report of 9 cases at a single institute

Background

Dedifferentiated chondrosarcomas consist of two distinguishable components: low-grade chondrosarcoma components and high-grade dedifferentiated components.

Materials and methods

Nine cases (4 males, 5 females) of dedifferentiated chondrosarcoma were treated in our institute. The average age was 58.6 (range, 37–86) years. The tumor location was the long bone in 7 cases (femur, n=5; humerus, n=1; tibia, n=1) and the pelvic bone in 2 cases. The average time from appearance of symptoms to treatment was 9.4 (range, 1–40) months.

Results and discussion

On plain radiographs, matrix mineralization was seen in all 9 cases (100%). Bone destruction was observed in 5 of 9 cases (56%), while pathological fracture was seen in one femur case (11%). Lung metastasis was observed in all cases (initially in 5 cases; during the treatment course in 4 cases). Surgery was performed in 8 cases, with local recurrence occurring in 2 of those cases (time to recurrence, 2 and 10 months). Chemotherapy was administered in 4 cases, but did not result in significant improvement. All 9 cases died of lung metastases, with a median survival time of 10 (range, 3.4-18.8) months. The presence of initial metastasis at diagnosis was a significant unfavorable prognostic factor.

Conclusion

The prognosis of dedifferentiated chondrosarcoma is dismal. With the lack of convincing evidence of the benefit of chemotherapy, complete surgical excision is the initial recommended treatment.

Postoperative DAV-IFN-β therapy does not improve survival rates of stage II and stage III melanoma patients significantly

BACKGROUND

DAV-interferon (IFN)-β therapy is a combination chemotherapy of dacarbazine (DTIC), nimustine (ACNU) and vincristine (VCR) with local subcutaneous injection of IFN-β that is widely employed as postoperative adjuvant chemotherapy to treat malignant melanoma in Japan. However, the efficacy of DAV-IFN-β therapy has not been confirmed by randomized controlled trials and the benefit of DAV-IFN-β therapy has not been established yet. This study evaluated the contribution of DAV-IFN-β therapy to improve survival of postoperative patients with cutaneous melanoma. Methods Patients with stage II or III cutaneous melanoma seen at Nagoya University Hospital from January 1998 to December 2009 were eligible for this study. Disease-free survival rates and melanoma-specific survival rates were evaluated. A propensity score was calculated to control for the effects of variables related to decisions regarding the application of DAV-IFN-β therapy.

RESULTS

Eighty-two stage II and 60 stage III melanoma patients were included. In the post-matched stage II patients (17 matched pairs), the mean (± SE) disease-free survival rates were 39.9 ± 13.7% for DAV-IFN-β therapy and 73.1 ± 11.7% for non-use (hazard ratio for recurrence, 2.06; 95% CI, 0.63-6.69; P = 0.23), and the melanoma-specific survival rates were 66.2 ± 20.0% for DAV-IFN-β therapy and 86.2 ± 9.1% for non-use (hazard ratio for death, 1.09; 95% CI, 0.17-6.82; P = 0.93). In the post-matched stage III patients (nine matched pairs), the disease-free survival rates were 29.6 ± 16.4% for DAV-IFN-β therapy and 33.3 ± 15.7% for non-use (0.69; 95% CI, 0.22-2.17; P = 0.53), and the melanoma-specific survival rates were 55.6 ± 16.6% for DAV-IFN-β therapy and 44.4 ± 16.6% for non-use (0.67; 95% CI, 0.18-2.50; P = 0.55).

CONCLUSIONS

DAV-IFN-β therapy brought no significant improvement in either disease-free survival rates or melanoma-specific survival rates of patients with stage II or III cutaneous melanoma. A randomized controlled trial would be required to further evaluate the efficacy of DAV-IFN-β therapy as an adjuvant chemotherapy.

Use of quantitative intra-operative electrodiagnosis during partial ulnar nerve transfer to restore elbow flexion

The transfer of part of the ulnar nerve to the musculocutaneous nerve, first described by Oberlin, can restore flexion of the elbow following brachial plexus injury. In this study we evaluated the additional benefits and effectiveness of quantitative electrodiagnosis to select a donor fascicle. Eight patients who had undergone transfer of a simple fascicle of the ulnar nerve to the motor branch of the musculocutaneous nerve were evaluated. In two early patients electrodiagnosis had not been used. In the remaining six patients, however, all fascicles of the ulnar nerve were separated and electrodiagnosis was performed after stimulation with a commercially available electromyographic system. In these procedures, recording electrodes were placed in flexor carpi ulnaris and the first dorsal interosseous. A single fascicle in the flexor carpi ulnaris in which a high amplitude had been recorded was selected as a donor and transferred to the musculocutaneous nerve. In the two patients who had not undergone electrodiagnosis, the recovery of biceps proved insufficient for normal use. Conversely, in the six patients in whom quantitative electrodiagnosis was used, elbow flexion recovered to an M4 level.

Quantitative intra-operative electrodiagnosis is an effective method of selecting a favourable donor fascicle during the Oberlin procedure. Moreover, fascicles showing a high-amplitude in reading flexor carpi ulnaris are donor nerves that can restore normal elbow flexion without intrinsic loss.

Potential bioavailability of phosphorus in citrus orchard soil to Microcystis aeruginosa

Algal blooms in eutrophic water bodies are controlled by inputs of phosphorus (P) as the growth-limiting nutrient. Runoff particulate P associated with soil from fields often predominates among P fractions. Here, an algal bioassay to investigate the potential bioavailability of particulate P in soil collected from a citrus orchard was conducted. Microcystis aeruginosa was cultured in medium containing soil as the sole source of P. The P in the soil was not notably solubilized after autoclaving. Analyses of chlorophyll-a, suspended solids, particulate organic carbon, and particulate organic nitrogen showed that M. aeruginosa could utilize some of the P present in the soil, perhaps that in particulate form, but this form of P was not sufficient to maintain optimum growth.

Induction of antibacterial activity in larvae of the blowfly Lucilia sericata by an infected environment

Maggot debridement therapy (MDT) is a method for the treatment of intractable, infected and necrotic wounds. In MDT, sterile larvae of Lucilia sericata Meigen (Diptera: Calliphoridae) are applied to infected wounds, where they exert antibacterial effects. Once the larvae are placed in the wound, they are no longer germ-free. This study analysed the influence of infected environments on larval antibacterial activities. Sterile larvae were mixed in a test tube containing a bacterial suspension of Staphylococcus aureus or Pseudomonas aeruginosa, transferred to liver puree agar, and incubated at 25 °C for set periods. To collect the larval extracts, the incubated larvae were transferred to a test tube containing phosphate buffered saline (PBS), cut into multiple pieces with scissors, and centrifuged. The supernatant was used to test antibacterial activities. The results showed that infected larvae had better antibacterial capacities than sterile larvae. Antibacterial activities were induced by pretreatment with a single bacterial species, S. aureus or P. aeruginosa, within 24 h and 12 h, respectively, and disappeared after 36 h. The activities were effective against S. aureus, but not against P. aeruginosa. This natural infection model is very similar to the clinical wound context in MDT and will be a powerful tool with which to study the antibacterial activities of L. sericata larvae in MDT.

Regulation of cellular immunity prevents Helicobacter pylori-induced atherosclerosis

Helicobacter pylori (H. pylori) is a predominant pathogen that causes not only gastroduodenal diseases but also extra-alimentary tract diseases. In this study, we demonstrated that H. pylori infection promoted atherogenesis in heterozygous apoe(+/ --) ldlr(+/--) mice. The male mice were fed with high fat diet from the age of 6 weeks. At the age of 16 weeks, development of atherosclerotic lesions was observed in the H. pylori-infected mice, and it seemed to be associated with an elevation of Th1-immune response against H. pylori origin-heat shock protein 60 (Hp-HSP60) and an increment of transendothelial migration of T cells. Subcutaneous immunisation with Hp-HSP60 or H. pylori eradication with antibiotics significantly reduced the progression of atherosclerosis, accompanied by a decline of Th1 differentiation and reduction of their chemotaxis beyond the endothelium. Thus, oral infection with H. pylori accelerates atherosclerosis in mice and the active immunisation with Hp-HSP60 or the eradication of H. pylori with antibiotics can moderate/prevent cellular immunity, resulting in a reduction of atherosclerosis.