| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Abd-el-Gawa, G, et al.
(författare)
-
Vitamin B12 and folate after 5-12 years of continent ileal urostomy (Kock reservoir) in children and adolescents.
- 2002
-
Ingår i: European urology. - : Elsevier BV. - 0302-2838. ; 41:2, s. 199-205
-
Tidskriftsartikel (refereegranskat)abstract
- To assess B12 and folate deficiency after continent urinary diversion via a Kock continent urinary reservoir in children and adolescents.Ten boys and 10 girls (10.8-18 years old at surgery) were operated with a Kock reservoir and followed for 5-12 years (mean 8.5). The follow-up period was divided into early (3 months-5 years, EFU) and late (5-12 years, LFU) follow-up. Patients were investigated for haemoglobin, serum iron, total iron binding capacity (TIBC), serum Vitamin B12, serum and blood folate, methylmalonic acid (MMA), homocystine and glomerular filtration rate.Two patients developed subnormal B12 values (median 107.5 pmol/l), one at the EFU, and the other at LFW. The B12 value decreased during the LFU compared to the EFU in nine patients, but it was still within the normal range. Two patients with renal impairment had elevated MMA with normal B12 values. Five patients had high values of homocystine with folate deficiency and/or B12 deficiency and renal impairment. Plasma folate mean value was normal during the whole follow-up. Blood folate was below normal in five patients at the EFU. Two of these five patients, in addition to three patients, had low values at the LFU. Three of four patients with remaining short terminal ileum (20-45 cm) had normal B12 values at both the EFU & LFU and one had low values at the LFU. Six patients had subnormal GFR at the LFU.To a similar degree as in adults, Vitamin B12, folate and iron deficiency can occur in children and adolescents after continent urinary diversion using an ileal segment. Therefore, Vitamin B12 and folate should be monitored regularly in these patients. Serum MMA and homocystine may offer increased detection of Vitamin B12 deficiency, especially in the patients with normal renal function. Vitamin B12 deficiency is neither correlated with the time elapsed since surgery, nor with the ileum length. Patients are usually asymptomatic, so patients with true B12 deficiency should be identified and placed on life-long Vitamin B12 therapy. An adequate synthetic folic acid as supplements or fortified food is recommended for patients with folate deficiency.
|
|
| 5. |
- Abrahamsson, Malin L. A.
(författare)
-
Electron Transfer in Ruthenium-Manganese Complexes for Artificial Photosynthesis : Studies in Solution and on Electrode Surfaces
- 2001
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In today’s society there is an increasing need for energy, an increase which for the most part is supplied by the use of fossil fuels. Fossil fuel resources are limited and their use has harmful effects on the environment, therefore the development of technologies that produce clean energy sources is very appealing. Natural photosynthesis is capable of converting solar energy into chemical energy through a series of efficient energy and electron transfer reactions with water as the only electron source. Thus, constructing an artificial system that uses the same principles to convert sunlight into electricity or storable fuels like hydrogen is one of the major forces driving artificial photosynthesis research.This thesis describes supramolecular complexes with the intention of mimicking the electron transfer reactions of the donor side in Photosystem II, where a manganese cluster together with a tyrosine catalyses the oxidation of water. All complexes are based on Ru(II)-trisbipyridine as a photosensitizer that is covalently linked to electron donors like tyrosine or manganese. Photochemical reactions are studied with time-resolved transient absorption and emission measurements. Electrochemical techniques are used to study the electrochemical behavior, and different photoelectrochemical techniques are used to investigate the complexes adsorbed onto titanium dioxide surfaces. In all complexes, intramolecular electron transfer occurs from the linked donor to photo-oxidized Ru(III). It is also observed that coordinated Mn(II) quenches the excited state of Ru(II), a reaction that is found to be distance dependent. However, by modifying one of the complexes, its excited state properties can be tuned in a way that decreases the quenching and keeps the electron transfer properties. The obtained results are of significance for the development of multinuclear Ru-Mn complexes that are capable of multi-electron transfer.
|
|
| 6. |
- Abrahamsson, M. L. A., et al.
(författare)
-
Ruthenium-manganese complexes for artificial photosynthesis : Factors controlling intramolecular electron transfer and excited-state quenching reactions
- 2002
-
Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 41:6, s. 1534-1544
-
Tidskriftsartikel (refereegranskat)abstract
- Continuing our work toward a system mimicking the electron-transfer steps from manganese to P-680(+) in photosystem II (PS II), we report a series of ruthenium(II)-manganese(II) complexes that display intramolecular electron transfer from manganese(II) to photooxidized ruthenium(III). The electron-transfer rate constant (k(ET)) values span a large range, 1 X 10(5)-2 x 10(7) s(-1), and we have investigated different factors that are responsible for the variation. The reorganization energies determined experimentally (lambda = 1.5-2.0 eV) are larger than expected for solvent reorganization in complexes of similar size in polar solvents (typically lambda approximate to 1.0 eV). This result indicates that the inner reorganization energy is relatively large and, consequently, that at moderate driving force values manganese complexes are not fast donors. Both the type of manganese ligand and the link between the two metals are shown to be of great importance to the electron-transfer rate. In contrast, we show that the quenching of the excited state of the ruthenium(II) moiety by manganese(II) in this series of complexes mainly depends on the distance between the metals. However, by synthetically modifying the sensitizer so that the lowest metal-to-ligand charge transfer state was localized on the nonbridging ruthenium(II) ligands, we could reduce the quenching rate constant in one complex by a factor of 700 without changing the bridging ligand. Still, the manganese(II)-ruthenium (III) electrontransfer rate constant was not reduced. Consequently, the modification resulted in a complex with very favorable properties.
|
|
| 7. |
- Abrahamsson, Per-Anders, et al.
(författare)
-
Calcitonin and calcitonin gene-related peptide in the human prostate gland
- 2000
-
Ingår i: The Prostate. - 0270-4137. ; 44:3, s. 181-186
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Calcitonin-related peptides have been found in the human prostate, and calcitonin (CT) and calcitonin gene-related peptide (CGRP) have been demonstrated in subpopulations of neuroendocrine (NE) cells. The purpose of this study was to determine the concentrations of CT and CGRP as well as the densities of NE cells in normal prostates, benign prostatic hyperplasia (BPH), and carcinoma of the prostate (CAP). METHODS: In 42 specimens of radical prostatectomy, the number of CT- and CGRP-immunoreactive NE cells in areas of normal and BPH tissue was determined, and compared with CAP tissue using immunocytochemistry. In addition, by radioimmunoassay (RIA), tissue levels of CT and CGRP were analyzed in extracts from areas of normal, BPH, and CAP tissue, as verified by adjacent histologic sections. RESULTS: A significant decrease in CT-immunoreactive NE cells was observed in hyperplastic nodules of BPH in comparison to normal tissue. These findings were in parallel with a significant reduction in tissue CT level in BPH compared to normal tissue. There was also a marked, but statistically nonsignificant, reduction in CT levels in CAP tissue. In contrast, levels of CGRP in BPH and CAP tissue did not show any significant differences compared to normal tissue. CONCLUSIONS: CT and CGRP are present in NE cells of the human prostate. Calcitonin levels are significantly reduced in BPH, in parallel with a decreased number of CT-immunoreactive NE cells, whereas no significant changes in tissue levels of CGRP were observed. The functional significance of these findings is discussed.
|
|
| 8. |
- Abrahamsson, Per-Anders, et al.
(författare)
-
Neuroendocrine Mediators in Prostate Cancer Progression
- 2002
-
Ingår i: Expanding Role of Octreotide I: Advances in Oncology. - 1 901978 13 3 ; , s. 279-279
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Recent years have seen a number of exciting developments in the evolving and expanding role of somatostatin and its analog, octreotide, in the diagnosis and treatment of cancer. It is now clear that octreotide has potential applications not just in imaging, but also in medical therapy and radiotherapy. This book contains the papers from a symposium held in September 2001 in Noordwijk in The Netherlands where all of these varied aspects of the expanding role of octreotide in clinical oncology were discussed.
|
|
| 9. |
|
|
| 10. |
- Berg, K. E., et al.
(författare)
-
Covalently linked ruthenium(II)-manganese(II) complexes : Distance dependence of quenching and electron transfer
- 2001
-
Ingår i: European Journal of Inorganic Chemistry. - 1434-1948 .- 1099-1948. ; 2001:4, s. 1019-1029
-
Tidskriftsartikel (refereegranskat)abstract
- Continuing our development of artificial models for photosystem II in green plants, a series of compounds have been prepared in which a RU(bpy)(3)(2+) photosensitizer is covalently Linked to a manganese(II) electron donor. In addition to a trispicolylamine Ligand, two other manganese Ligands, dipicolylamine and aminodiacetic acid, have been introduced in order to study Ligands that are appropriate for the construction of manganese dimers with open coordination sites for the binding of water. Coordination equilibria of the manganese ions were monitored by EPR. The interactions between the ruthenium and manganese moieties were probed by flash photolysis, cyclic voltammetry and steady-state and time-resolved emission measurements. The quenching of the Ru-II excited state by Mn-II was found to be rapid in complexes with short Ru-Mn distances. Nevertheless, each Run species could be photo-oxidized by bimolecular quenching with methylviologen, and the subsequent electron transfer from Mn-II to Ru-III could be monitored.
|
|
