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71.
Bone response to a single bout of exercise can be observed with biochemical markers of bone formation and resorption. The purpose of this study was to examine the response of bone biochemical markers to a single bout of exhaustive high-impact exercise. 15 physically active young subjects volunteered to participate. The subjects performed continuous bilateral jumping with the ankle plantarflexors at 65 % of maximal ground reaction force (GRF) until exhaustion. Loading was characterized by analyzing the GRF recorded for the duration of the exercise. Venous blood samples were taken at baseline, immediately after, 2h and on day 1 and day 2 after the exercise. Procollagen type I amino terminal propeptide (P1NP, marker of bone formation) and carboxyterminal crosslinked telopeptide (CTx, marker of bone resorption) were analyzed from the blood samples. CTx increased significantly (32 %, p = 0.015) two days after the exercise and there was a tendensy towards increase seen in P1NP (p = 0.053) one day after the exercise. A significant positive correlation (r = 0.49 to 0.69, p ≤ 0.038) was observed between change in P1NP from baseline to day 1 and exercise variables (maximal slope of acceleration, body weight (BW) adjusted maximal GRF, BW adjusted GRF exercise intensity and osteogenic index). Based on the two biochemical bone turnover markers, it can be concluded that bone turnover is increased in response to a very strenuous single bout of exhaustive high-impact exercise.

Key points

  • Studies on bone acute biochemical response to loading have yielded unequivocal results.
  • There is a paucity of research on the biochemical bone response to high impact exercise.
  • An increase in bone turnover was observed one to two days post exercise.
Key words: Bone biochemical marker, jumping, bone turnover, osteogenic index  相似文献   
72.

Background

Overall therapeutic outcomes of advanced non-small-cell lung cancer (NSCLC) are poor. The dendritic cell (DC) immunotherapy has been developed as a new strategy for the treatment of lung cancer. The purpose of this study was to evaluate the feasibility, safety and immunologic responses in use in mature, antigen-pulsed autologous DC vaccine in NSCLC patients.

Methods

Five HLA-A2 patients with inoperable stage III or IV NSCLC were selected to receive two doses of 5 × 107 DC cells administered subcutaneous and intravenously two times at two week intervals. The immunologic response, safety and tolerability to the vaccine were evaluated by the lymphoproliferation assay and clinical and laboratorial evolution, respectively.

Results

The dose of the vaccine has shown to be safe and well tolerated. The lymphoproliferation assay showed an improvement in the specific immune response after the immunization, with a significant response after the second dose (p = 0.005). This response was not long lasting and a tendency to reduction two weeks after the second dose of the vaccine was observed. Two patients had a survival almost twice greater than the expected average and were the only ones that expressed HER-2 and CEA together.

Conclusion

Despite the small sample size, the results on the immune response, safety and tolerability, combined with the results of other studies, are encouraging to the conduction of a large clinical trial with multiples doses in patients with early lung cancer who underwent surgical treatment.

Trial Registration

Current Controlled Trials: ISRCTN45563569  相似文献   
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Genetic diversity in malaria vaccine antigens may compromise malaria vaccine efficacy, so it is important to understand this diversity and the processes that generate it. By applying new high-throughput genotyping methods to a large sample of infections from Mali (N = 1369), seven new 19-kDa merozoite surface protein 1 (MSP-1(19)) haplotypes were identified. Herein we report the sequences of these new haplotypes and discuss their possible origins. Although they are present in < 1% of the samples examined, the existence of these rare haplotypes reveals a greater degree of diversity at this locus than previously reported and highlights the potential for Plasmodium to evolve under selective pressure from the immune system and from such interventions as vaccines and drugs.  相似文献   
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OBJECTIVE: To evaluate splanchnic tissue perfusion, assessed by gastric tonometry, in patients with subarachnoid hemorrhage (SAH) and to study the effect of treatment, either surgical or endovascular, and the severity of initial SAH on splanchnic tissue perfusion. DESIGN: Prospective observational substudy, part of a randomised controlled trial of early treatment of ruptured intracranial aneurysms. SETTING: Intensive care unit (ICU) of a university hospital. PATIENTS: A consecutive sample of 26 patients [13 surgical (7/6 Hunt & Hess Grade I-II/H & H Gr IV-V) and 13 endovascular (3/10 H & H Gr I-II/H & H Gr IV-V)] out of 56 SAH patients randomly assigned to either endovascular or surgical treatment during the substudy period between 1 May 1995 and 31 August 1996. All patients were treated within 72 h after SAH. MEASUREMENTS AND RESULTS: After treatment of a ruptured aneurysm, hemodynamics and gastric intramucosal pCO2 were measured during the first 4 h and between 6 h and 12 h after aneurysm treatment. In the whole sample, neither the gastric intramucosal-arterial pCO2 difference (pCO2 gap) (1.5+/-1.9 kPa and 1.7+/-1.2 kPa, NS) nor gastric intramucosal pH (7.28+/-0.12 and 7.29+/-0.08, NS) changed during the study. There were no differences in pCO2 gap or gastric intramucosal pH between treatment groups or Hunt & Hess grade groups during the study period. CONCLUSIONS: Splanchnic tissue perfusion may be insufficient even though there is no systemic hemodynamic disturbance in patients after SAH. Neither the therapeutic treatment nor pre-treatment Hunt & Hess grade is associated with a specific pattern of pCO2 gap.  相似文献   
79.
Branched-chain amino acids (BCAA) stimulate muscle and liver protein synthesis in vitro. The significance of this action in catabolic conditions in vivo remains controversial. The effects of a high supply of BCAA in total parenteral nutrition (TPN) on nitrogen balance and liver protein synthesis were studied in a postoperative rat model. After standard operative trauma TPN was commenced with one of two isocaloric programs (I: 20.1% BCAA and II: 50% BCAA) and continued for 48 hr. The relative rate of liver protein synthesis, measured after TPN in vitro by perfusion with 14C-leucine, was similar in both groups (I: 53.4 +/- 17.3 and II: 49.0 +/- 27.3 arbitrary units of synthesis rate, mean +/- SD). The cumulative nitrogen balance was positive with both regimens and was not improved by the high supply of BCAA (I: 2.02 +/- 0.81 and II: 1.87 +/- 0.63 gN/kg/48 hr mean +/- SD). We conclude that after moderate surgical trauma TPN with a high supply of BCAA offers no advantage over conventional TPN.  相似文献   
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