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91.
Andrea Dueregger Isabel Heidegger Philipp Ofer Bernhard Perktold Reinhold Ramoner Helmut Klocker Iris E. Eder 《Nutrients》2014,6(10):4491-4519
Prostate cancer (PCa), the most commonly diagnosed cancer and second leading cause of male cancer death in Western societies, is typically androgen-dependent, a characteristic that underlies the rationale of androgen deprivation therapy (ADT). Approximately 90% of patients initially respond to ADT strategies, however many experience side effects including hot flashes, cardiotoxicity, metabolic and musculoskeletal alterations. This review summarizes pre-clinical and clinical studies investigating the ability of dietary supplements to alleviate adverse effects arising from ADT. In particular, we focus on herbal compounds, phytoestrogens, selenium (Se), fatty acids (FA), calcium, and Vitamins D and E. Indeed, there is some evidence that calcium and Vitamin D can prevent the development of osteoporosis during ADT. On the other hand, caution should be taken with the antioxidants Se and Vitamin E until the basis underlying their respective association with type 2 diabetes mellitus and PCa tumor development has been clarified. However, many other promising supplements have not yet been subjected large-scale clinical trials making it difficult to assess their efficacy. Given the demographic trend of increased PCa diagnoses and dependence on ADT as a major therapeutic strategy, further studies are required to objectively evaluate these supplements as adjuvant for PCa patients receiving ADT. 相似文献
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Electron paramagnetic resonance studies of photosynthetic electron transport: Photoreduction of ferredoxin and membrane-bound iron-sulfur centers 下载免费PDF全文
Daniel I. Arnon Harry Y. Tsujimoto Tetsuo Hiyama 《Proceedings of the National Academy of Sciences of the United States of America》1977,74(9):3826-3830
Electron paramagnetic resonance spectrometry was used to investigate, at physiological temperatures, light-induced electron transport from membrane-bound iron-sulfur components (bound ferredoxin) to soluble ferredoxin and NADP(+) in membrane fragments (from the blue-green alga, Nostoc muscorum) that had high rates of electron transport from water to NADP(+) and from an artificial electron donor, reduced dichlorophenolindophenol (DCIPH(2)) to NADP(+). Illumination at 20 degrees resulted in the photoreduction of membrane-bound iron-sulfur centers A and B. Photoreduction by water gave electron paramagnetic resonance signals of both centers A and B; photoreduction by DCIPH(2) was found to generate a strong electron paramagnetic signal of only center B.When water was the reductant, the addition and photoreduction of soluble ferredoxin generated additional signals characteristics of soluble ferredoxin without causing a decrease in the amplitude of the signals due to centers A and B. The further addition of NADP(+) (and its photoreduction) greatly diminished signals due to the bound iron-sulfur centers and to soluble ferredoxin. An outflow of electrons from center B to soluble ferredoxin and NADP(+) was particularly pronounced when DCIPH(2) was the reductant. These observations provide the first evidence for a light-induced electron transport between membrane-bound iron-sulfur centers and ferredoxin-NADP(+). The relationship of these observations to current concepts of photosynthetic electron transport is discussed. 相似文献
96.
Anti-influenza response achieved by immunization with a synthetic conjugate. 总被引:13,自引:12,他引:13 下载免费PDF全文
G M Müller M Shapira R Arnon 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(2):569-573
The peptide corresponding to sequence 91--108 of the hemagglutinin of type A H3N2 influenza virus has been synthesized by the solid-phase peptide synthesis method and covalently attached to several macromolecular carriers. The conjugate with tetanus toxoid was used for immunization of rabbits and mice. The immunoglobulin fraction of the rabbit antiserum showed the presence and antipeptide antibodies by both agar gel diffusion and radioimmunoassay. In the latter assay, the antibodies showed marked crossreactivity with the intact virus of the A/Texas/77 strain. The antibodies were also capable of inhibiting the hemagglutination of chicken erythrocytes by the virus; the highest hemagglutination inhibition titer (1:32) was achieved with a serum-resistant strain of A/Texas/77. When the in vitro virus plaque formation assay was used with monolayers of Madin--Darby canine kidney (MDCK) cells, the number of plaques was reduced on interaction with the immunoglobulin fraction of the antiserum, which was effective up to a dilution of 1:32. Preliminary results indicate that C3H/DiSn mice immunized with the peptide--tetanus toxoid conjugate are partially protected against a further challenge with A/Texas mouse-adapted influenza virus. The results are thus indicative of the efficacy of the synthetic material in eliciting anti-influenza immune response. 相似文献
97.
Rubin AE Polotsky VY Balbir A Krishnan JA Schwartz AR Smith PL Fitzgerald RS Tankersley CG Shirahata M O'Donnell CP 《American journal of respiratory and critical care medicine》2003,168(12):1520-1527
In obstructive sleep apnea, hypoxic ventilatory sensitivity may affect the degree of hypoxic stress and sleep disruption that occurs in response to upper airway obstruction. We induced (1) sleep-induced hypoxia (SIH) or (2) sleep fragmentation (SF) without hypoxia for 5 days (12-hour light/dark cycle) in two inbred mouse strains with low (A/J) and high (DBA/2J) hypoxic ventilatory sensitivities. During SIH, the time to arousal (26.4 +/- 1.1 vs. 21.3 +/- 1.5 seconds, p<0.025) and the severity of hypoxic exposure (nadir FIO2: 11.5 +/- 0.4 vs. 13.6 +/- 0.1%, p<0.002) was greater in A/J than DBA/2J mice. Furthermore, A/J mice had a greater frequency of hypoxic events (640 +/- 29 vs. 368 +/- 33 events per 24 hours, p<0.001) and total sleep time (47.5 +/- 2.8% vs. 26.5 +/- 2.4% per 24 hours, p<0.0001) during SIH than DBA/2J mice. In contrast, the event characteristics and total sleep time during SF were the same in both strains. Furthermore, in the light phase, both strains showed a longer (p<0.01) time to arousal during SIH and SF compared with the dark phase. We conclude that genetic background can influence respiratory events and sleep architecture during SIH and that the arousal threshold is subject to circadian variation. Our data imply that individuals with low hypoxic sensitivity may be at a greater risk for hypoxia-related complications of obstructive sleep apnea. 相似文献
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Kröger N Sayer HG Schwerdtfeger R Kiehl M Nagler A Renges H Zabelina T Fehse B Ayuk F Wittkowsky G Schmitz N Zander AR 《Blood》2002,100(12):3919-3924
We investigated the feasibility of unrelated stem cell transplantation in 21 patients with advanced stage II/III multiple myeloma after a reduced-intensity conditioning regimen consisting of fludarabine (150 mg/m(2)), melphalan (100-140 mg/m(2)), and antithymocyte globulin (ATG; 10 mg/kg on 3 days). The median patient age was 50 years (range, 32-61 years). All patients had received at least one prior autologous transplantation, in 9 cases as part of an autologous-allogeneic tandem protocol. No graft failure was observed. At day 40 complete donor chimerism was detected in all patients. Grade II to IV acute graft-versus-host disease (GVHD) was seen in 8 patients (38%), and severe grade III/IV GVHD was observed in 4 patients (19%). Six patients (37%) developed chronic GVHD, but only 2 patients (12%) experienced extensive chronic GVHD. The estimated probability of nonrelapse mortality at day 100 was 10% and at 1 year was 26%. After allografting, 40% of the patients achieved a complete remission, and 50% achieved a partial remission, resulting in an overall response rate of 90%. After a median follow-up of 13 months, the 2-year estimated overall and progression-free survival rates are 74% (95% CI, 54%-94%) and 53% (95% CI, 29%-87%), respectively. A shorter progression-free survival was seen in patients who already experienced relapse to prior autograft (26% versus 86%, P =.04). Dose-reduced conditioning with pretransplantation ATG followed by unrelated stem cell transplantation provides durable engraftment and donor chimerism, reduces substantially the risk of transplant-related organ toxicity, and induces high remission rates. 相似文献
100.
Arnon Blum Shlomo Laniado Hylton Miller Giora Kaplan Nurit Vardinon Israel Yust Michael Burke 《Clinical cardiology》1998,21(9):655-658
Background: Elevation of acute phase proteins [C-reactive protein (CRP) and serum amyloid type A (SAA)] has been demonstrated in unstable angina with an adverse clinical prognosis. Hypothesis: The study was undertaken to determine the effect of angioplasty on the levels of SAA and the correlation with postangioplasty restenosis. Methods: In a university-affiliated tertiary medical center, a prospective case study was undertaken in 55 patients who underwent successful percutaneous transluminal coronary angioplasty (PTCA) of a single coronary lesion for angina pectoris. Three groups of patients were clinically characterized according to Braunwald's classification of anginal syndrome: Group A: class III; Group B: class I; Group C: stable angina. Serum amyloid type A was measured by an ELISA method before PICA and after 24 h, 1, and 3 months. Patients were followed clinically for 12 months. A thallium stress perfusion scan was performed 3 months after PTCA and coronary angiography was repeated in patients with an abnormal thallium perfusion scan. Results: Serum amyloid type A levels >100 m?/ml could identify Group A patients with a high sensitivity and specificity (r = 0.85 and 0.86, respectively). Of the patients studied. 75% increased their SAA level 24 h after angioplasty. An increase of SAA by >100% was associated with an increased risk of restenosis, with a relative risk of 6.4 (p < 0.05). Conclusion: Increased levels of SAA characterize patients with unstable angina pectoris with a high specificity and sensitivity. Levels of SAA that increase > 100% 24 h after angioplasty may serve as a marker of restenosis. 相似文献