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Subramaniam Puvaneswary Hanumantha Rao Balaji Raghavendran Nurul Syuhada Ibrahim Malliga Raman Murali Azhar Mahmood Merican T. Kamarul 《International journal of medical sciences》2013,10(12):1608-1614
The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system. 相似文献
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HbA1c values are heavily relied on to assess glycemic control. Hemoglobin variants may interfere with measurements of HbA1c resulting in falsely low values. We present the first report of a rare variant of Hb in a patient with type 2 diabetes, which lead to a falsely low HbA1c. 相似文献
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Semiquinone radical intermediate in catecholic estrogen-mediated cytotoxicity and mutagenesis: chemoprevention strategies with antioxidants
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Samuni AM Chuang EY Krishna MC Stein W DeGraff W Russo A Mitchell JB 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(9):5390-5395
Modulation of the cytotoxicity and mutagenicity of 4-hydroxyestradiol (4-OHE(2)), an oxidative metabolite of estrogen, by antioxidants was assessed in human MCF7 cells and TK-6 lymphoblast cells. The cytotoxicity of the catecholic estrogens was potentiated by depletion of intracellular glutathione and was independent of oxygen concentration. Agents such as the nitroxide Tempol can facilitate the oxidation of the semiquinone to the Q and enhanced 4-OHE(2) cytotoxicity. Conversely, reducing agents such as ascorbate, cysteine, and 1,4-dihydroxytetramethylpiperidine (THP) protected against cytotoxicity and decreased mutation induction, presumably by reducing the semiquinone to the hydroquinone. Our results support the proposition that oxidation of the semiquinone to the corresponding Q is crucial in eliciting the deleterious effects of catecholic estrogens. Furthermore, because the deleterious effects of 4-OHE(2) were abrogated by dietary and synthetic antioxidants, our results would support the chemopreventive use of diets rich in reducing substances (vitamins and added synthetic antioxidants) as a means of decreasing the risks associated with estrogen exposure and developing of breast cancer. 相似文献
55.
Doraiswamy PM Khan ZM Donahue RM Richard NE 《The journals of gerontology. Series A, Biological sciences and medical sciences》2002,57(2):M134-M137
BACKGROUND: Although recurrent major depression in elderly individuals is a disabling condition, only a few studies have systematically examined the magnitude and specificity of quality-of-life (QOL) impairments in such patients in comparison with matched controls or the elderly population. METHODS: We examined the variations in QOL scores of 100 elderly (age range 60-88 years) patients with moderate to severe recurrent major depression and compared them with published elderly population norms. Disease-specific Quality of Life in Depression Scale (QLDS) and generic Medical Outcomes Short Form-36 Health Survey (SF-36) QOL ratings obtained at baseline were analyzed. RESULTS: Compared with published elderly population norms, depressed subjects showed significant QOL impairments in five of eight baseline SF-36 items (p <.01). Women rated their QOL as worse than men on physical functioning and role physical (p <.01) and showed similar trends on all other QOL items. Compared with younger subjects, subjects aged older than 70 years reported lower QOL on the summary physical component (p <.01) and a trend for higher QOL on the summary mental component (p <.05) of the SF-36. Depression symptom ratings were correlated with some QOL measures, but accounted for less than 10% of the variance. CONCLUSIONS: Despite limitations, such as a cross-sectional design and indirect comparisons with norms generated from another study, our findings confirm the disabling nature of recurrent late-life depression and the importance of targeting both depressive symptoms and broader QOL outcomes in intervention trials. 相似文献
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This is an overview of radiological imaging of the hand highlighting the various imaging modalities used in the work-up and diagnosis of a range of orthopaedic and rheumatological disorders. The biomechanics and anatomy of the human hand is extremely complex, and a good understanding is required to diagnose pathology. In this article we explain the anatomy and highlight pathology of the hand from a radiological perspective with respect to plain film, CT, ultrasound and MR imaging. Trauma of the hand is extremely common and radiology plays an important role in the diagnosis of treatable injuries including fractures, dislocations and ligament tears. Plain radiography and CT are excellent at evaluating bony injury (e.g. Rolondo or Bennett's fracture) whereas ultrasound and MR are better at evaluating soft tissue injury (e.g. Stener lesion). The hands are a common location for degenerate and inflammatory arthropathies which all have hallmark radiological features. Radiology also plays an important role in the diagnosis and work-up of bone lesions in the hand including enchondromas, osteoid osteomas and chondrosarcomas. 相似文献
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Pressman GS Figueredo VM Romero-Corral A Murali G Kotler MN 《The American journal of cardiology》2012,109(7):1055-1059
Obstructive apneas produce high negative intrathoracic pressure that imposes an afterload burden on the left ventricle. Such episodes might produce structural changes in the left ventricle over time. Doppler echocardiograms were obtained within 2 months of attended polysomnography. Patients were grouped according to apnea-hypopnea index (AHI): mild/no obstructive sleep apnea (OSA; AHI <15) and moderate/severe OSA (AHI ≥15). Mitral valve tenting height and area, left ventricular (LV) long and short axes, and LV end-diastolic volume were measured in addition to tissue Doppler parameters. Comparisons of measurements at baseline and follow-up between and within groups were obtained; correlations between absolute changes (Δ) in echocardiographic parameters were also performed. After a mean follow-up of 240 days mitral valve tenting height increased significantly (1.17 ± 0.12 to 1.28 ± 0.17 cm, p = 0.001) in moderate/severe OSA as did tenting area (2.30 ± 0.41 to 2.66 ± 0.60 cm(2), p = 0.0002); Δtenting height correlated with ΔLV end-diastolic volume (rho 0.43, p = 0.01) and Δtenting area (rho 0.35, p = 0.04). In patients with mild/no OSA there was no significant change in tenting height; there was a borderline significant increase in tenting area (2.20 ± 0.44 to 2.31 ± 0.43 cm(2), p = 0.05). Septal tissue Doppler early diastolic wave decreased (8.04 ± 2.49 to 7.10 ± 1.83 cm/s, p = 0.005) in subjects with moderate/severe OSA but not in in those with mild/no OSA. In conclusion, in patients with moderate/severe OSA, mitral valve tenting height and tenting area increase significantly over time. This appears to be related, at least in part, to changes in LV geometry. 相似文献