| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Cinco, R M, et al.
(författare)
-
Orientation of calcium in the Mn4Ca cluster of the oxygen-evolving complex determined using polarized strontium EXAFS of photosystem II membranes
- 2004
-
Ingår i: Biochemistry. - Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Melvin Calvin Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. : AMER CHEMICAL SOC. - 0006-2960 .- 1520-4995. ; 43:42, s. 13271-13282
-
Tidskriftsartikel (refereegranskat)abstract
- The oxygen-evolving complex of photosystem II (PS II) in green plants and algae contains a cluster of four Mn atoms in the active site, which catalyzes the photoinduced oxidation of water to dioxygen. Along with Mn, calcium and chloride ions are necessary cofactors for proper functioning of the complex. The current Study using polarized Sr EXAFS on oriented Sr-reactivated samples shows that Fourier peak II, which fits best to Mn at 3.5 Angstrom rather than lighter atoms (C, N, O, or Cl), is dichroic, with a larger magnitude at 10degrees (angle between the PS II membrane normal and the X-ray electric field vector) and a smaller magnitude at 80degrees. Analysis of the dichroism of the Sr EXAFS yields a lower and upper limit of 0degrees and 23degrees for the average angle between the Sr-Mn vectors and the membrane normal and an isotropic coordination number (number of Mn neighbors to Sr) of 1 or 2 for these layered PS II samples. The results confirm the contention that Ca (Sr) is proximal to the Mn cluster and lead to refined working models of the heteronuclear Mn4Ca cluster of the oxygen-evolving complex in PS II.
|
|
| 8. |
- Teo, Koon K., et al.
(författare)
-
Effects of telmisartan, irbesartan, valsartan, candesartan, and losartan on cancers in 15 trials enrolling 138 769 individuals The ARB Trialists Collaboration
- 2011
-
Ingår i: Journal of Hypertension. - 0263-6352 .- 1473-5598. ; 29:4, s. 623-635
-
Forskningsöversikt (refereegranskat)abstract
- Background Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARBs) reduce cardiovascular disease (CVD) events, but a recent meta-analysis of selected studies suggested that ARBs may increase cancer risks.Objective Candesartan, irbesartan, telmisartan, valsartan, and losartan were assessed for incident cancers in 15 large parallel long-term multicenter double-blind clinical trials of these agents involving 138 769 participants.Patients and methods Individuals at high CVD risk were randomized to telmisartan (three trials, n=51 878), irbesartan (three trials, n=14 859), valsartan (four trials, n=44 264), candesartan (four trials, n=18 566), and losartan (one trial, n=9193) and followed for 23-60 months. Incident cancer cases were compared in patients randomized to ARBs versus controls. In five trials (n=42 403), the ARBs were compared to ACEi and in 11 trials (n=63 313) to controls without ACEi. In addition, in seven trials (n=47 020), the effect of ARBs with ACEi was compared to ACEi alone and in two trials ARBs with ACEi versus ARB alone (n=25 712).Results Overall, there was no excess of cancer incidence with ARB therapy compared to controls in the 15 trials [ 4549 (6.16%) cases of 73 808 allocated to ARB versus 3856 (6.31%) of 61 106 assigned to non-ARB controls; odds ratio (OR) 1.00, 95% confidence interval (CI) 0.95-1.04] overall or when individual ARBs were examined. ORs comparing combination therapy with ARB along with ACEi versus ACEi was 1.01 (95% CI 0.94-1.10), combination versus ARB alone 1.02 (95% CI 0.91-1.13), ARB alone versus ACEi alone 1.06 (95% CI 0.97-1.16) and ARB versus placebo/control without ACEi 0.97 (95% CI 0.91-1.04). There was no excess of lung, prostate or breast cancer, or overall cancer deaths associated with ARB treatment.Conclusion There was no significant increase in the overall or site-specific cancer risk from ARBs compared to controls.
|
|
| 9. |
|
|
| 10. |
|
|
