The role of polyamine architecture on the pharmacological activity of open lactone camptothecin-polyamine conjugates

A series of camptothecin open-ring lactone tripartate conjugates were synthesized, in which polyamine side chains with different architecture (ethane-1,2-diamine, spermidine, homospermidine, spermine, and 4,8,13,17-tetraza-icosane-1,20-diamine) are linked to the 21-carboxylic function through an amidic bond, while the 17-CH(2)OH is acetylated. The rationale for the synthesis of these compounds was to explore the influence of the polyamine architecture on the activity of these CPT conjugates into cells, since the positively charged ammonium cations would favor interaction through electrostatic binding to the negatively charged DNA backbone. Topoisomerase I-mediated DNA cleavage assay was used to investigate the ability of these compounds to stimulate the DNA damage. The cleavage pattern was found to be similar to that of SN38 for all the new CPTs. The CPT tripartates were tested for growth inhibition ability against the human non-small-cell lung cancer carcinoma NCI-H460 cell line. Although these compounds were less potent than topotecan, SN38, and CPT after 1 h of treatment, the antiproliferative effects greatly increased after 72 h of exposure. The growth inhibition potency during long-term exposure is correlated with the number of charges of the 21-amide substituent. Both cleavage assay and in vitro effects support the interpretation that the compounds may have inhibitory activity also in the open-ring form. The architecture of the polyamine moiety is important for antiproliferative activity, and a balance between the hydrophilic and lipophilic properties of the polyamine is critical for CPT potency.     

Absorption and fluorescence spectra of ring-substituted indole-3-acetic acids

The absorption and fluorescence spectra of indole-3-acetic acid (1), a plant growth regulator (auxin) and experimental cancer therapeutic, 29 ring-substituted derivatives and the 7-aza analogue (1H-pyrrolo[2,3b]pyridine-3-acetic acid) are compared. Two to four absorbance maxima in the 260-310-nm range are interpreted as overlapping vibronic lines of the 1La<--1A and 1Lb<--1A transitions. Two further maxima in the 200-230-nm region are assigned to the 1Ba<--1A and 1Bb<--1A transitions. 4- and 7-Fluoroindole-3-acetic acid exhibit blue shifts with respect to 1, most other derivatives show red shifts. All indole-3-acetic acids studied, with the exception of chloro-, bromo- and 4- or 7-fluoro-derivatives, fluoresce at 345-370 nm when excited at 275-280 nm. 7-Azaindole-3-acetic acid emits at 411 nm. The fluorescence quantum yield of 6-fluoroindole-3-acetic acid significantly exceeds that of 1 (0.3); the other derivatives have lower quantum yields. The plant-growth promoting activity of the ring-substituted indole-3-acetic acids studied correlates with the position of the 1Bb<--1A transition band.     

Metatarsal metastasis from transitional cell cancer of the urinary bladder

Urinary bladder cancers can be grouped into three general categories: superficial, invasive and metastatic. Approximately 90% of malignant tumors of the urinary bladder are of epithelial origin and the majority of them are transitional cell carcinomas (TCC). Metastatic spread of urinary bladder cancers usually includes regional lymph nodes, the lung, the liver and the bones. The presence of metastasis tends to correlate with muscular wall invasion as often demonstrated at the initial diagnosis; consequently clinical bladder cancer represents a late phase of the disease. Although skeletal metastases of bladder cancers are rather common, they have been rarely described to occur in distal bones. For that reason, we report metatarsal metastasis from transitional cell cancer of the urinary bladder in a 59-year-old woman.     

Identification of a cooperative mechanism involving interleukin-13 and eotaxin-2 in experimental allergic lung inflammation

Pulmonary eosinophilia, a hallmark pathologic feature of allergic lung disease, is regulated by interleukin-13 (IL-13) as well as the eotaxin chemokines, but the specific role of these cytokines and their cooperative interaction are only partially understood. First, we elucidated the essential role of IL-13 in the induction of the eotaxins by comparing IL-13 gene-targeted mice with wild type control mice by using an ovalbumin-induced model of allergic airway inflammation. Notably, ovalbumin-induced expressions of eotaxin-1 and eotaxin-2 mRNA in the lungs were almost completely dependent upon IL-13. Second, in order to address the specific role of eotaxin-2 in IL-13-induced pulmonary eosinophilia, we generated eotaxin-2 gene-deficient mice by homologous recombination. Notably, in contrast to observations made in eotaxin-1-deficient mice, eotaxin-2-deficient mice had normal base-line eosinophil levels in the hematopoietic tissues and gastrointestinal tract. However, following intratracheal IL-13 administration, eotaxin-2-deficient mice showed a profound reduction in airway eosinophilia compared with wild type mice. Most interestingly, the level of peribronchial lung tissue eosinophils in IL-13-treated eotaxin-2-deficient mice was indistinguishable from wild type mice. Furthermore, IL-13 lung transgenic mice genetically engineered to be deficient in eotaxin-2 had a marked reduction of luminal eosinophils. Mechanistic analysis identified IL13-induced eotaxin-2 expression by macrophages in a distinct lung compartment (luminal inflammatory cells) compared with eotaxin-1, which was expressed solely in the tissue. Taken together, these results demonstrate a cooperative mechanism between IL-13 and eotaxin-2. In particular, IL-13 mediates allergen-induced eotaxin-2 expression, and eotaxin-2 mediates IL-13-induced airway eosinophilia.     

Effects of doxorubicin and its aglycone metabolite on calcium sequestration by rabbit heart, liver, and kidney mitochondria

Previous investigators have shown that following doxorubicin treatment heart mitochondria appear swollen and contain intramitochondrial dense inclusion bodies identified as calcium phosphate. In vitro studies have shown that similar morphological changes occur in mitochondria previously loaded with excess calcium. The present studies were performed to determine the effects of doxorubicin and its aglycone metabolite on ⁴⁵Ca²⁺ uptake by mitochondria isolated from the heart, liver, and kidney of the rabbit. Doxorubicin (100 μM) significantly inhibited the initial rate of ⁴⁵Ca²⁺ accumulated by mitochondria isolated from the three tissues. In contrast, the aglycone metabolite (100 μM) induced the reverse effect. In preloaded mitochondria the aglycone stimulated the release of calcium while doxorubicin was without effect. Mitochondria from the heart were significantly more sensitive to the effects of these anthracyclines than were mitochondria from the other two tissues. If these in vitro effects also occur in vitro, then the aglycone metabolite would be a more likely candidate in explaining the morphological changes in heart mitochondria previously described.     

Synovial chondromatosis of the pisotriquetral joint with secondary osteoarthritis: case report

There are only a few reported cases of synovial chondromatosis affecting pisotriquetral joint (PT). Osteoarthritis of the PT is also rare and can be as disabling as osteoarthritis of any other joint. We report this to be the unique case of synovial chondromatosis of the PT joint with secondary osteoarthritis.     

Fungal community structure under goat willows (Salix caprea L.) growing at metal polluted site: the potential of screening in a model phytostabilisation study

Goat willow (Salix caprea L.) was selected in a previous vegetation screening study as a potential candidate for the later-stage phytostabilisation efforts at a heavily metal polluted site in Slovenia. The aims of this study were to identify the fungi colonising roots of S. caprea along the gradient of vegetation succession and to estimate their colonisation levels in relation to metal pollution in order to reveal its mycorrhizal status at the site. Additionally the metal accumulation capacity of S. caprea and photosynthetic pigments were analysed as indications of its fitness at four differentially polluted plots. Despite high concentrations of leaf accumulated Cd, no significant differences in photosynthetic pigment concentrations were observed. The roots were colonised by arbuscular mycorrhizal (AM) fungi, ectomycorrhizal (EM) fungi, and dark septate endophytes (DSE), with EM as the dominant type on all the plots. Molecular characterisation showed poor correlation of the root EM community with the above-ground sporocarp diversity. Members of Sordariaceae were the most frequent colonisers with an average colonisation of 21% of all root tips, followed by Thelephoraceae with 10%. DSE colonisation increased with increasing Pb concentrations and decreasing organic matter (OM).