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Sfar S El Heni J Laporte F Braham H Jawed A Amor S Sfar MT Kerkeni A 《Experimental gerontology》2012,47(3):243-249
Micronutrients as well as essential fatty acids are indispensable for the correct functioning of the organism. The risk of disturbance in the associated nutrition and metabolism is expected to increase during ageing. In addition, it seems that trace elements are involved in the fatty acids metabolism. The aim of the present study was then to assess age-related changes in trace elements status and in plasma essential fatty acids composition with an emphasis on the desaturase activity estimation. Two hundred healthy Tunisian subjects (30-85 years old) were recruited and separated into two subgroups: elderly (65-85 years old) and middle-aged (30-60 years old). The findings revealed that plasma zinc and calcium concentrations significantly decreased according to age. The prevalence of zinc deficiency was therefore shown to increase in old age (over 60% of elderly subjects were deficient or at risk of deficiency). No age-related changes were obtained for copper or magnesium status. The Δ6 desaturase, involved in the EFAs conversion, was shown to decrease according to age and to be associated with the plasma zinc level. Since elderly subjects were at risk of nutritional imbalance, it would be interesting to set optimal dietary proportion. This will help to prevent age-associated alterations and diseases for a better and healthy ageing. 相似文献
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Kaya H Peressini B Jawed I Martincic D Elaimy AL Lamoreaux WT Fairbanks RK Weeks KA Lee CM 《International journal of hematology》2012,95(1):64-70
With the availability of novel agents, the overall survival (OS) in patients diagnosed with multiple myeloma (MM) has improved
over the last decade. Data on 40,294 MM patients in the years from 1973 to 2003 were obtained from the Surveillance, Epidemiology,
and End Results Program (SEER) of the US National Cancer Institute. Statistical analyses evaluating gender, race, age, and
year of diagnosis were performed using univariate and multivariate Cox regression models for the OS endpoint. The mean patient
age at diagnosis was 68.3 years. Mean survival was 30 months (median = 19 months). Asian/Pacific Islander race was associated
with an improved OS, HR 0.90 (CI 0.86–0.95, P < 0.001). American Indian/Alaska Native race was associated with a decreased OS, HR 1.18 (CI 1.01–1.38, P = 0.040). Multivariate analysis did not reveal statistically significant differences in OS between patients in the white
and black race (P = 0.709). Younger age (age <65, and 65–75) was associated with improved OS when compared with patients >75 years of age (all
P < 0.001). Recent treatment decades (1983–1992 and 1993–2003) were associated with improved OS on multivariate analysis with
HR 0.88 (CI 0.88–0.89, P < 0.001) and HR 0.83 (CI 0.81–0.85, P < 0.001), respectively. As the largest population analysis to date, this study reveals a statistically significant improvement
in OS for patients who were treated in more recent decades, even before the availability of novel agents. Patients who were
<65 years of age and Asian/Pacific Islander race groups exhibited superior levels of OS, whereas American Indian/Alaska Native
groups had decreased OS. 相似文献
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Jeske W Litinas E Khan H Hoppensteadt D Fareed J 《Clinical and applied thrombosis/hemostasis》2012,18(3):294-298
Pharmacodynamic behavior of branded and biosimilar enoxaparin was compared in a crossover study in primates. Blood samples collected at baseline and at 1, 4, 6, and 28 hours post-subcutaneous administration of Lovenox or Fibrinox were evaluated using clot-based and amidolytic assays. Anti-Xa levels following Fibrinox and Lovenox administration were not different. Anti-IIa levels were significantly higher in Lovenox-treated animals 1 to 6 hours post-administration. Higher drug levels were measured by Heptest in Fibrinox-treated animals from 4 to 6 hours. Pharmacokinetic differences were not observed using anti-Xa or Heptest assays. The area under the curve (anti-IIa) following Lovenox treatment was significantly larger than following Fibrinox treatment. When drug levels (anti-IIa) were plotted against anti-Xa or Heptest drug levels, a hysteretic relationship which was distinct for Fibrinox- and Lovenox-treated primates was observed suggesting a lack of bioequivalence for the low-molecular-weight heparin tested. In vivo behavior is an important consideration for defining pharmacoequivalence of complex biologic drugs. 相似文献
48.
Lima MA de Farias EH Gray A Sadeghi N Gesteira TF Cavalheiro RP Hoppensteadt D Fareed J Sassaki GL Nader HB 《Clinical and applied thrombosis/hemostasis》2012,18(4):379-386
Generic active pharmaceutical ingredients (APIs) have been commonly used in Brazil, since 1999, but most of them are synthetic and small molecules. Recently, a large number of generic enoxaparins were introduced into the market raising concerns related to product-to-product interchangeability, efficiency, and drug counterfeiting. These drugs are produced from biological sources and their production involves complex procedures and purification processes. The present article evaluates several generic enoxaparins, structurally and pharmacologically, and compares them with the branded products. Structural analysis showed that the generic products are, indeed, quite similar to the branded products, however, this similarity cannot be extended to their pharmacological activities. The results showed that generic products must go through extensive structural, pharmacological, and clinical evaluation in order to assess their quality, efficacy and, ultimately, avoid drug counterfeiting before clinical use. Variation was also observed between the branded products, showing that such drugs must be at constant surveillance. 相似文献
49.
De La Pe?a A Fareed J Thethi I Morales-Vidal S Schneck MJ Shafer D 《Clinical and applied thrombosis/hemostasis》2012,18(3):324-326
Chronic immune thrombocytopenia (ITP) carries a poor prognosis in the elderly patients. Increasing evidence proposes that a subgroup of patients with chronic ITP may be more susceptible to ischemic stroke. An 84-year-old Caucasian man with multiple ischemic stroke risk factors presented with acute onset of slurred speech, confusion, and unsteady gait. Physical examination and neurologic imaging were consistent with a new left thalamic infarct. Platelet counts ranged between 40 000 × 10(9)/L and 65 000 × 10(9) /L. Antiplatelet therapy for his newly acquired stroke was not initiated considering his low platelet counts and for mildly symptomatic thrombocytopenia, and the patient was discharged home. Both hematologic and neurologic guidelines for the management of chronic ITP and stroke have contradictory goals. Although anticoagulation is mandated in acute stroke, ITP causes low platelet counts that increase bleeding complications. 相似文献
50.
Thethi I Bansal V Khan H Hoppensteadt D Fareed J 《Clinical and applied thrombosis/hemostasis》2012,18(5):534-537
Patients with end-stage renal disease (ESRD) are known to have an elevation of a variety of abnormal thrombotic and inflammatory markers associated with high cardiovascular mortality. Vascular endothelial growth factor (VEGF) is also dysregulated in ESRD but not much is known about the serum levels of VEGF in patients with ESRD. Published reports suggest that elevated levels of VEGF may be protective to the kidney during periods of acute injury and may maintain local glomerular function. Impaired production of VEGF may lead to proteinuria, hypertension, and thrombotic microangiopathy. However, its role in chronic kidney disease or ESRD remains undefined. In our study, we analyzed blood samples of 52 patients with ESRD on stable hemodialysis regimen and measured predialysis serum levels of VEGF and compared these with blood samples obtained from 50 healthy volunteers in order to study differences between baseline levels of VEGF and also attempted to determine its role in ESRD-related cardiovascular mortality. 相似文献