Early lifetime zinc supplementation protects zinc-deficient diet-induced alterations

Preclinical and clinical data indicate the involvement of zinc in the pathophysiology and therapy of depression. A relationship between zinc-deficiency and depression symptoms was recently proposed. The present study investigated alterations in spontaneous locomotor activity and zinc concentrations in the serum, hippocampus and frontal cortex; these alterations were induced by subjecting rats to a zinc-deficient diet, prior subjected after birth to zinc-supplemented diet. Body weight was significantly reduced in animals subjected to the four-week zinc-deficient diet compared to those subjected to the zinc-adequate diet. The two-week zinc-deficient diet induced a significant increase in locomotor activity in all measured time periods (5, 30 and 60 min by 44-62%). The four-week zinc-deficient diet did not affect locomotor activity, while the six-week zinc-deficient diet resulted in a 45% increase in the 5 min time period. Serum zinc concentrations were significantly reduced (by 29%) in animals subjected to the four-week zinc-deficient diet but not in those subjected to the two- or six-week zinc-deficient diets. The zinc-deficient diet did not influence the zinc concentration in the examined brain regions regardless of the length. These results indicate that post-birth supplementation with zinc may protect zinc-deficient diet-induced rapid alterations in zinc homeostasis.     

恶性淋巴瘤危险因素病例对照研究

[目的]探讨恶性淋巴瘤发病的危险因素。[方法]采用1：2配比病例对照研究的方法，对南通市及其周围地区48例经细胞学或病理学确诊的恶性淋巴瘤患者及96例对照进行问卷调查，相关资料采用条件Logistic回归分析。[结果]三废污染（OR=3.07,90%CI1.23-7.67)、有机溶剂（OR=3.88,90%CI1.18-13.97)、避孕药（OR=2.26,90%CI1.15-6.60)、家族肿瘤史（OR=17.30,90%CI4.42-57.66)和饮酒（OR=0.66,90%CI 0.43-1.00)与恶性淋巴瘤的发病有关。[结论]三废污染、有机溶剂、避孕药和家族肿瘤史可能是恶性淋巴瘤的危险因素，而少量饮酒可以降低恶性淋巴瘤的发病危险性。     

Extracellular calcium increases bisphosphonate-induced growth inhibition of breast cancer cells

Introduction

Bisphosphonates have become standard therapy for the treatment of skeletal complications related to breast cancer. Although their therapeutic effects mainly result from an inhibition of osteoclastic bone resorption, in vitro data indicate that they also act directly on breast cancer cells, inhibiting proliferation and inducing apoptosis.

Methods

The present study examined the effects of calcium (from 0.6 to 2.0 mmol/l) on the antitumour activity of the bisphosphonate ibandronate (1 to 1,000 nmol/l) on MDA-MB-231 and MCF-7 breast cancer cells. Cell culture densities were determined using crystal violet staining assay. Apoptotic cell death was assessed by annexin V-phycoerythrin and 7-amino-actinomycin double staining.

Results

At low calcium concentration, 30 μmol/l ibandronate had no effect on MDA-MB-231 cells growth and only slightly inhibited MCF-7 cells growth. Higher calcium levels significantly increased growth inhibition as well as cell apoptosis induced by ibandronate. We observed similar effects with zoledronic acid. Of note, enhancement of ibandronate-induced growth inhibition was also observed in other breast cancer cell lines (T-47D, ZR-75, Hs-578T and BT-549 cells). The growth inhibitory effect of ibandronate in the presence of high concentrations of calcium was partly suppressed by the calcium chelator EGTA (ethylene glycol tetra-acetic acid). In addition, in the presence of calcium at high concentrations, cells accumulated more [¹⁴C]ibandronate than at low calcium concentrations. We obtained further evidence of enhancement of cellular ibandronate accumulation by calcium by demonstrating that high calcium levels increased the inhibition of protein prenylation induced by the bisphosphonate.

Conclusion

Altogether, our data suggest that extracellular calcium, probably through its binding to ibandronate, markedly increased its cellular accumulation and its inhibitory activity on breast tumour cells. Thus, calcium released during the process of tumour-induced osteolysis might enhance the antitumour effects of bisphosphonates and contribute to their therapeutic efficacy.     

Conceptualization of differing levels of educational attainment: what are the characteristics of nurses and midwives who have undertaken diploma and degree educational programmes?

This paper looks at the differences in the characteristics of registered nurses and midwives who have achieved differing levels of educational attainment. A review of the pertinent literature demonstrates that there is little published material on this topic and therefore, proposals are put forward with regard to a conceptual model to frame outcome characteristics. The model is seen as being appropriate when trying to identify the different characteristics of nurses and midwives educated to diploma, degree, postgraduate diploma, masters and doctoral level. The model is subsequently applied to identifying core outcomes and composite statements of nurses and midwives who have undertaken diploma or degree programmes. Initial work examining the validity and reliability of the core outcomes and composite statements with regard to degree preparation is described. Areas for further research are also identified.