Impact of severity, duration, and etiology of hyperthyroidism on bone turnover markers and bone mineral density in men

<p>Abstract</p> <p>Background</p> <p>Hyperthyroidism is accompanied by osteoporosis with higher incidence of fracture rates. The present work aimed to study bone status in hyperthyroidism and to elucidate the impact of severity, duration, and etiology of hyperthyroidism on biochemical markers of bone turnover and bone mineral density (BMD).</p> <p>Methods</p> <p>Fifty-two male patients with hyperthyroidism, 31 with Graves' disease (GD) and 21 with toxic multinodular goiter (TNG), with an age ranging from 23 to 65 years were included, together with 25 healthy euthyroid men with matched age as a control group. In addition to full clinical examination, patients and controls were subjected to measurement of BMD using dual-energy X-ray absorptiometery scanning of the lower half of the left radius. Also, some biochemical markers of bone turnover were done for all patients and controls.</p> <p>Results</p> <p>Biochemical markers of bone turnover: included serum bone specific alkaline phosphatase, osteocalcin, carboxy terminal telopeptide of type l collagen also, urinary deoxypyridinoline cross-links (DXP), urinary DXP/urinary creatinine ratio and urinary calcium/urinary creatinine ratio were significantly higher in patients with GD and TNG compared to controls (P < 0.01). However, there was non-significant difference in these parameters between GD and TNG patients (P > 0.05). BMD was significantly lower in GD and TNG compared to controls, but the Z-score of BMD at the lower half of the left radius in patients with GD (-1.7 ± 0.5 SD) was not significantly different from those with TNG (-1.6 ± 0.6 SD) (>0.05). There was significant positive correlation between free T3 and free T4 with biochemical markers of bone turnover, but negative correlation between TSH and those biochemical markers of bone turnover. The duration of the thyrotoxic state positively correlated with the assessed bone turnover markers, but it is negatively correlated with the Z-score of BMD in the studied hyperthyroid patients (r = -0.68, P < 0.0001).</p> <p>Conclusion</p> <p>Men with hyperthyroidism have significant bone loss with higher biochemical markers of bone turnover. The severity and the duration of the thyrotoxic state are directly related to the derangement of biochemical markers of bone turnover and bone loss.</p

Comparative performance of DG mixes and SMA mixes with waste crumb rubber as aggregate replacement

This research paper presents a comparative study on the performance of asphalt mixes containing waste crumb rubber as an aggregate replacement. Two different mixes namely Dense Graded (DG) and Stone Matrix Asphalt (SMA) with different ratios of waste crumb rubber WCR (0.5%, 1.0%, 1.5%, and 2.0% by weight of aggregate) were produced. The performance tests including, Marshall stability, Marshall Quotient (MQ), tensile strength, tensile strength ratio, and deformation strength in Kim test were carried out on DG and SMA asphalt mixtures. The analyses of test results show that the performance of DG-mixtures is better than SMA-mixtures in term of Marshall stability, and Marshall Quotient and lower indirect tensile strength, and Deformation Strength than SMA mixes. The moisture susceptibility and temperature susceptibility can be reduced by the inclusion of waste crumb rubber in the DG asphalt mixture. A waste crumb rubber content of 0–1.0% by weight of aggregate is recommended for the aggregate replacement of the performance of asphalt concrete mixtures similar to that investigated in this study

World Cup 2010 Traffic simulation long-term aging of polypropylene asphalt paving mixtures

Paper presented at the 26th Annual Southern African Transport Conference 9 - 12 July 2007 "The challenges of implementing policy?", CSIR International Convention Centre, Pretoria, South Africa. ABSTRACT: This study investigated the influence of accelerated weathering (aging) on the engineering properties of modified asphalt mixtures with pyrolysis polypropylene (PP). The accelerated weathering was done at a temperature of 85 °C and over two periods of time, namely between two and four days. Marshall specimens were compacted with a mechanical compactor at a temperature of 135 to 142 °C. Five pyrolysis polypropylene mixtures, including the control, which had an optimum asphalt content, were investigated. The asphalt concrete was of a dense-graded aggregate type of surface course conforming to the gradation limits of ASTM highway commission specifications. The results showed that variations in age change the physical properties of modified mixtures.This paper was transferred from the original CD ROM created for this conference. The material on the CD ROM was published using Adobe Acrobat technology. The original CD ROM was produced by Document Transformation Technologies Postal Address: PO Box 560 Irene 0062 South Africa. Tel.: +27 12 667 2074 Fax: +27 12 667 2766 E-mail: [email protected] URL: http://www.doctech.co.z