Trace elements are chemical elements in minute quantities, which are known to accumulate in the bone. Cortical and trabecular bones consist of bone structural units (BSUs) such as osteons and bone packets of different mineral content and are separated by cement lines. Previous studies investigating trace elements in bone lacked resolution and therefore very little is known about the local concentration of zinc (Zn), strontium (Sr) and lead (Pb) in BSUs of human bone. We used synchrotron radiation induced micro X-ray fluorescence analysis (SR μ-XRF) in combination with quantitative backscattered electron imaging (qBEI) to determine the distribution and accumulation of Zn, Sr, and Pb in human bone tissue.Fourteen human bone samples (10 femoral necks and 4 femoral heads) from individuals with osteoporotic femoral neck fractures as well as from healthy individuals were analyzed. Fluorescence intensity maps were matched with BE images and correlated with calcium (Ca) content. We found that Zn and Pb had significantly increased levels in the cement lines of all samples compared to the surrounding mineralized bone matrix. Pb and Sr levels were found to be correlated with the degree of mineralization. Interestingly, Zn intensities had no correlation with Ca levels. We have shown for the first time that there is a differential accumulation of the trace elements Zn, Pb and Sr in BSUs of human bone indicating different mechanisms of accumulation.
Extensive surgical resection of supratentorial gliomas increases survival. However, some reports suggest that the perioperative morbidity and mortality outweigh the potential benefit of the procedure. We examined prospectively morbidity and mortality in 104 consecutive patients who underwent surgery for supratentorial glioma, as well as other factors that might affect the short-term outcome. To determine if our experience was unusual, we compared these results with those obtained from another academic neurosurgical center by a review of the records of 109 patients also treated surgically for supratentorial glioma. Mortality was 3.3% and the medical plus neurologic morbidity was 31.7%. Functionally significant neurologic worsening occurred in 42 (19.7%) patients. Complications were more frequent in patients with moderate or severe preoperative disabilities than those with mild or no preoperative disability. Patients with complete resection had fewer acute neurologic complications, and no greater risk of being neurologically impaired at 1 week, than patients with biopsy or less extensive procedures. Morbidity and mortality correlated with location: deep-midline lesions had a higher overall rate of perioperative complications (p = 0.032) and mortality (p = 0.019) and bilateral lesions a higher rate of hemorrhage (p = 0.017) and hydrocephalus (p = 0.010). Older patients (greater than 55 years) and those receiving high daily dose of preoperative dexamethasone (greater than or equal to 24 mg) had a significantly higher risk of surgical mortality. Reoperation for recurrent tumor carried no greater risk of mortality, neurologic deterioration, and infection than a first operation.(ABSTRACT TRUNCATED AT 250 WORDS)
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