Four tumour active trinuclear complexes: DH4Cl: [{trans-PtCl(NH3)2}2m-{trans-Pd( NH3)2(H2N(CH2)4NH2)2]Cl4, DH5Cl: [{trans-PtCl(NH3)2}2m-{trans-Pd( NH3)2(H2N(CH2)5NH2)2]Cl4, DH6Cl: [{trans-PtCl(NH3)2}2m-{trans-Pd( NH3)2(H2N(CH2)6NH2)2]Cl4, DH7Cl: [{trans-PtCl(NH3)2}2m-{trans-Pd(NH3)2-( H2N(CH2)7NH2)2]Cl4 and one dinuclear complex DHD: [{trans-PtCl(NH3)2}�-{ H2N(CH2)6NH2}{trans-PdCl(NH3)2]Cl(NO3), have been prepared and characterised based on elemental analyses, IR, Raman, mass and 1 H NMR spectral measurements. For the trinuclear complexes, the synthesis has been carried out using a step-up method branching out from the central palladium unit. A purity of about 95% has been obtained by repeated dissolution and precipitation. The activity against human cancer cell lines including ovary cell lines: A2780, A2780 cisR , A2780 ZD0473R , non small lung cell line: NCI-H640 and melanoma: Me-10538 have been determined based on MMT assay. Cell uptakes, DNA-binding have been determined for ovary cell lines: A2780, A2780 cisR . The nature of interaction with pBR322 plasmid DNA and ssDNA has been studied for trinuclear complexes DH4Cl, DH5Cl, DH6Cl and DH7Cl and the dinuclear complex DHD. Interaction of DH6Cl with adenine and guanine has also been studied by HPLC. The compounds are found to exhibit significant anticancer activity against cancer cell lines especially ovarian cancer cell lines: A2780, A2780 cisR and A2780 ZD0473R . DH6Cl in which the linking diamine has six carbon atoms is found to be the most active compound. As the number of carbon atoms in thelinking diamine is changed from the optimum value of six, the activity is found to decrease, illustrating the structure-activity relationship. The increase in uptake of the trinuclear complexes in A2780 cell line with the increase in size of the linking diamine coupled with the low molar conductivity values found for the solutions of the compounds suggest that the compounds would remain in solution as undissociated �molecules� and hence could cross the cell membrane by passive diffusion. Much lower resistance factors for the all the multinuclear compounds including DHD as applied to A2780 cisR cell line, as compared to that for cisplatin, suggest that the compounds are able to overcome multiple mechanisms of resistance operating in the cell line. All of the multinuclear complexes are expected to form long-range interstrand GG adducts with DNA, causing irreversible global changes in the DNA conformation but unlike cisplatin do not cause sufficient DNA bending to be recognized by HMG 1 protein. Increasing prevention of BamH1 digestion with the increase in concentration of the multinuclear compounds also provide support to the idea that the compounds because of the formation of a plethora of interstrand GG adducts are able to cause irreversible changes in DNA conformation. The results of the study show that indeed new trinuclear tumour active compounds can be found by replacing the central platinum unit in BBR3464 with other suitable metal units.

The South Burnett region of Queensland is Australia's most important rainfed peanut (Arachis hypogea L.) production area. It also produces a considerable amount of cereal and grain legume crops. The cropping soils of the region are red, acid to neutral, clay loams that are classified as Ferrosols (Australian Soil Classification). Over 50 years of cropping on these soils has resulted in severe depletion of nutrient reserves, particularly potassium (K). In addition, the remaining K is predominantly confined to the surface 10 or 15cm of the soil profile, a feature commonly refered to as nutrient stratification. Dry periods during the summer cropping season are common due to the highly variable, summer-dominant rainfall pattern of the South Burnett. As topsoil dries out, crops forage for moisture and nutrients from lower in the soil profile where K reserves are smaller. It is therefore suspected that the combination of dry periods and stratified K reserves have resulted in an increasing incidence of K deficiency symptoms in summer crops. To investigate these issues, K relations of Ferrosols of the South Burnett were studied using soils from two representative sites. The pools of soil K that are important to crop growth in Ferrosols, and their interaction was examined through fractionation of soil K pools, and determination of quantity/intensity relationships, charge characteristics and clay mineralogy, and a leaching column study. A rapid K uptake period was identified for peanut and the effect of profile distribution and soil moisture during this period on K accessibility was studied in a divided column experiment. Finally, on-farm trials were used to evaluate commercial-scale options for improving K distribution in field profiles. It was found that the immediately available exchangeable K pool in these soils was the most important source of soil K, and was poorly buffered by slowly available non-exchangeable K. However the leaching column study revealed that K was preferentially adsorbed onto soil cation exchange sites, displacing calcium (Ca) and magnesium (Mg) ions, and therefore was not susceptible to vertical movement within the soil profile. These observations helped to explain the development of stratified K profiles in these soil types. Peanut (cv. Streeton) was found to take up most of its K requirement between 25-70 days after planting. The divided column study showed that profile distribution, and topsoil iv moisture content during this rapid K uptake period, were able to affect the ability of peanut plants to access K. Plants that grew in low K soil, or where soil was dry at the site of K supply, had reduced access to K. However, improving access to K did not result in improved growth, but rather in a significant reduction in dry matter (DM) production, apparently due to interference in the availability of other nutrients, possibly phosphorus (P), magnesium (Mg) or boron (B). Field studies showed that application of K and profile inversion improved K uptake and DM production of various crop species. However, in most instances improved K uptake and DM production was not reflected in increased yield. It was suggested that a combination of agronomic factors, seasonal conditions and crop type prevented the expression of yield responses to improved K nutrition and these influences need to be understood. The findings of this project have important consequences for nutrition of crops grown on Ferrosols in the South Burnett region. Surface applied K cannot be expected to increase exchangeable K in the subsoil unless it is incorporated to depth. Similarly, band applied K will remain close to the site of application as a result of only limited vertical or lateral movement. This may affect the ability of roots to access band applied K. The ability of surface applied K to displace Ca and Mg from soil exchange sites may have negative implications for the Ca nutrition of developing peanut pods. On the other hand, it could present an opportunity for the movement of Ca into deeper soil layers to address the amelioration of acid subsoils. The unexplained negative responses to potassium chloride application and apparent effect on P, Mg or B nutrition need to be investigated.

Diss. (sammanfattning) Stockholm : Karolinska institutet 2005. / I publ. felaktigt ISBN: 91-7140-442-4. Härtill 6 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 5 uppsatser.

Diss. (sammanfattning). Umeå : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Diss. (sammanfattning). Umeå : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Linköping : Univ., 2003. / Härtill 4 uppsatser.