Resveratrol induces apoptotic cell death in rat H4IIE hepatoma cells but necrosis in C6 glioma cells

Resveratrol (trans-3,5,4',-trihydroxystilbene) is assumed to possess cancer-preventive and cancer-therapeutic properties. The aim of this project was to analyze cellular effects of resveratrol in metabolically active H4IIE rat hepatoma cells in comparison to metabolically poorly active C6 rat glioma cells. Resveratrol is rapidly taken up by both cell types and acts as a potent intracellular antioxidant. On the other hand, resveratrol in higher concentrations is relatively toxic to both cell lines as measured by the neutral red accumulation assay. In H4IIE cells, resveratrol concentrations rapidly decline to very low levels during the first hours of incubation due to formation of resveratrol glucuronides. The first resveratrol effect found at 3h after the start of resveratrol treatment was the induction of mild DNA damage as detected by the comet assay. Cell death was caused via induction of apoptosis as detected by caspase activation, oligonucleosomal DNA fragmentation and formation of apoptotic nuclei. Following DNA damage, resveratrol led to an activation of caspases 2 and 8/10 at 6h and consequently of caspase 3 at 12h, but failed to activate caspase 9. In contrast to H4IIE cells, resveratrol is not metabolised in C6 glioma cells and accumulates to concentrations which are assumed to drive the cell into necrosis. This suggests that the mode of cell death caused by resveratrol and the usefulness of resveratrol for cancer prevention and treatment critically depends on the metabolic capacity of the tumor cell to be eradicated.

[Six-minute-walking-test with and without oxygen in patients with COPD: comparison of walking distance and oxygen saturation in varying forms of application]

BACKGROUND

Patients afflicted with COPD and respiratory Failure often experience a decrease of oxygen saturation (SaO (2)) under physical strain. The aim of our study was to find out which changes occur in walking distance and SaO (2) under the application of Oxygen (O (2)) 2 l/min continous flow, under demand (D) and under normal air (RL) when performing the Six-Minute-Walking-Test (6MWT) and further, in which way do the 10 patients of the shortest walking distance group (group I) differ from the eo patients with the longest walking distance (group II) concerning the starter 6 MWT (under CF).

METHOD AND PATIENTS

27 patients undertook a 6MWT three days in a row with CF, D and (RL), 6 minutes before (phase I), during (phase II) and after (phase III) the 6MWT oxygen was applied in CF (day I), D (day II) and RL (day III), the mean oxygen saturation in each phase was measured and the change (DeltaSaO (2)) during and after the 6MWT was calculated. Additionally we measured the DeltaSaO (2) between start and middle, as well as between middle and end of each phase. In close proximity to the tests FEV (1) and pO (2) was determined.

RESULTS

In the total of all test persons there was no significant difference in the walking distance tetween the 3 forms of application. There was, however, a highly significant decrease of the oxygen saturation. The decrease in the two forms of oxygen application did not differ significantly. The decrease of SaO (2) under strain and the consecutive rise under rest occurred within the first 3 minutes of each phase. Patients of group II were often able to increase their walking distance under RL, whereas patients of group I decreased their walking distance further. In group II FEV (1) abs. was significantly higher, but FEV (1) % debit and pO (2) did not differ significantly between both groups.

CONCLUSIONS

Patients with a long walking distance showed a marked learning effect even under RL, they presented a higher FEV (1), but not an increased pO (2). The phase of resaturation after the end of strain is short. Oxygen application through a demand valve with a flow rate of 2 l/min is not inferior to a continuous flow. In more than half of all patients the SaO (2) fell below 90 % under both forms of oxygen application, in conclusion the flow rate should be increased in these cases.

Copolymeric polythioesters by lipase-catalyzed thioesterification and transthioesterification of α,ω-alkanedithiols

Linear copolymeric polythioesters [PTE; poly(alpha,omega-alkanedioic acid-co-alpha,omega-alkanedithiols)] were formed in good yield (approximately 69%) by thioesterification of 1,12-dodecanedioic acid with 1,6-hexanedithiol and 1,8-octanedithiol, respectively, catalyzed by immobilized lipase from Rhizomucor miehei (Lipozyme RM IM) in vacuo without a solvent. Similarly, transthioesterification (thiolysis) of diethyl 1,12-dodecanedioate with 1,6-hexanedithiol led to the formation of approximately 66% PTE. Poly (1,12-dodecanedioic acid-co-1,6-hexanedithiol) and poly (1,12-dodecanedioic acid-co-1,8-octanedithiol) were extracted from the reaction mixture using methyl-t-butylether, precipitated at -20 degrees C and the precipitates extracted with boiling i-hexane to yield two fractions of PTE. The i-hexane-insoluble fraction of poly (1,12-dodecanedioic acid-co-1,6-hexanedithiol) shows an average molecular mass (Mw) of 1,212 Da, corresponding to a molecular weight range of up to 13,200 Da and a degree of polymerization of up to 38 monomer units. The i-hexane-insoluble fraction of poly (1,12-dodecanedioic acid-co-1,8-octanedithiol) shows a Mw of 2,360 Da, corresponding to a molecular weight range of up to 19,500 Da and a maximum degree of polymerization of up to 52 monomer units. The low-molecular weight (<800 Da) reaction products of thioesterification of 1,12-dodecanedioic acid with 1,6-hexanedithiol, elucidated by gas chromatography-mass spectroscopy, show the following intermediates: (1) 9,20-dioxo-1,8-dithiacycloeicosane; (2) 17,28-dioxo-1,8,9,16-tetrathiacyclooctacosane; (3) 1,12-dodecanedioic acid methyl(O)ester 6'-S-mercaptohexyl thio(S)ester; and (4) oligomeric linear thioester, formed by thioesterification of two molecules of 1,12-dodecanedioic acid with one molecule of 1,6-hexanedithiol.

Biosynthesis of storage lipids in plant cell and embryo cultures

The biosynthesis of storage lipids in plant cell and embryo cultures is discussed in the light of their significance in the breeding of agriculturally important oil seed crops. After a short introduction to the biosynthesis of storage lipids, i.e. triacylglycerols and wax esters, this review covers the occurrence and biosynthesis of storage lipids in plant cell and embryo cultures. Plant cells in culture generally contain low levels of both unusual fatty acids and triacylglycerols indicating that these cells are quite different from cells of oil storage tissues. There are a few exceptions to this rule which demonstrate that induction of genes involved in the expression of fatty acid modification and triacylglycerol assembly is possible in plant cell cultures. Such biosynthetically active plant cells may be of particular interest in future studies of storage lipid assembly. Both somatic and gametophytic embryos of oil plants exhibit high capacities for storage lipid biosynthesis and accumulation in vitro compared to cultured plant cells. Above all, the microspore-derived embryo system is recommended to both plant breeders and plant biochemists for the selection and multiplication of plants of superior quality.

Characterization of the nuclear import of human MutLalpha

DNA mismatch repair (MMR) is essential for the maintenance of replication fidelity. Its major task is to recognize mismatches as well as insertion/deletion loops of newly synthesized DNA strands. Although different players of human MMR have been identified, the regulation of essential steps of MMR is poorly understood. Because MMR is initiated in the nucleus, nuclear import might be a mechanism to regulate MMR. Nuclear targeting is accomplished by conserved signal sequences called nuclear localization signals (NLS), which represent clusters of positively charged amino acids (aa). hMLH1 contains two clusters of positively charged amino acids, which are candidate NLS sequences (aa 469-472 and 496-499), while hPMS2 contains one (aa 574-580). To study the effect of these clusters on nuclear import, NLS mutants of hMLH1 and hPMS2 were generated and expressed in 293T cells. The subcellular localization of the mutant constructs was monitored by confocal laser microscopy. We demonstrated that missense mutations of two signal sequences, one in hMLH1 and one in hPMS2, lead to impaired nuclear import, which was especially prominent for mutants of the hMLH1 residues K471 and R472; and hPMS2 residues K577 and R578.

Optimum peripheral drug deposition in patients with cystic fibrosis

In order to identify the optimum particle size and breathing pattern for high peripheral deposition of inhaled drugs in patients with cystic fibrosis, regional deposition in these patients was studied systematically as a function of particle size, inhalation volume and flow rate. Regional deposition was assessed using the single-breath regional deposition technique in which the concentration profile of inhaled and exhaled non-radioactive, monodisperse test particles is analyzed. Using this technique particle deposition within the functional dead space volume and peripherally can be assessed. Regional deposition was measured in 12 patients with cystic fibrosis using 2, 3, 4, and 5.5 microm particles, inhalation volumes of 500, 1000, 1500, and 2000 cm(3), and inhalation flow rates of 100, 250, 500, and 750 cm(3)/sec. Peripheral deposition was highest when 2-3-microm particles were inhaled with air-flow rates of 250-500 cm(3)/sec. With these parameters peripheral deposition increased with increasing inhalation volume and reached values of about 60% of the total drug inhaled. It has been shown that high peripheral drug deposition can be achieved in patients with CF when inhalations are performed using an optimized combination of particle size and breathing pattern.

Characterization of a population of small macrophages in induced sputum of patients with chronic obstructive pulmonary disease and healthy volunteers

The inflammatory process in chronic obstructive pulmonary disease (COPD) is active mainly in the airways, but little is known about the properties of the inflammatory cells in this compartment. We have studied leucocytes in induced sputum of COPD patients compared to controls in order to uncover what types of macrophages might be involved in the disease. Sputum induction was performed by inhalation of nebulized sodium chloride solution. Leucocytes were isolated and stained with specific monoclonal antibodies for analysis in flow cytometry. Flow cytometry analysis revealed that a major portion of CD14+ macrophages in COPD has lower forward scatter, i.e. they are small macrophages. While in control donors these small macrophages accounted for 6.9% of all macrophages, the percentage of these cells in COPD was 45.7%. CD14 and HLA-DR expression was high on these small sputum macrophages while the large sputum macrophages expressed only low levels of these surface molecules, both in control donors and COPD patients. Small sputum macrophages of both control donors and COPD patients showed higher levels of constitutive tumour necrosis factor (TNF) compared to the large macrophages. TNF was inducible by lipopolysaccharide (LPS) preferentially in the small sputum macrophages in the control donors but there was no further induction in COPD patients. These data show that the small sputum macrophages are a major macrophage population in COPD and that these cells exhibit features of highly active inflammatory cells and may therefore be instrumental in airway inflammation in COPD.

[The ovarian hyperstimulation syndrome -- a rare differential diagnosis of a unilateral pleural effusion]

This case presentation describes a 29 year-old female who developed a severe ovarian hyperstimulation syndrome (OHSS) with ascites and a right-sided pleural effusion following in-vitro-fertilisation. A total of 4,2 l of pleural fluid was removed during 3 thoracocenteses. The symptoms as well as the fluid production ceased after 2 weeks. The OHSS is altogether a rare, but potentially life-threatening complication of in-vitro-fertilisation. Due to the well-characterized clinical setting in which the syndrome appears, there are only few differential diagnoses to consider. OHSS is likely to originate from altered capillary permeability, but its pathogenesis is not yet fully understood. Clinical symptoms usually resolve within 2 weeks of supportive therapy. In case of persistency, however, especially pulmonary embolism and infectious causes of pleural fluid production have to be excluded.

[Xenon - noble gas with organprotective properties]

Besides it's anaesthetic properties, xenon may induce biological effects that may protect various organs from ischaemia-reperfusion injury. Xenon is an antagonist of the NMDA-receptor and reduces the neuronal injury mediated via these receptors. In contrast to other NMDA-receptor antagonists, xenon has no neurotoxic side effects. Xenon also protects the heart in ischaemia-reperfusion situations. Xenon reduces the post-ischaemic reperfusion injury and offers cardioprotection by inducing pharmacological preconditioning. These organ protective properties of xenon might be useful in special clinical situations.

Mono-thioesters and di-thioesters by lipase-catalyzed reactions of alpha,omega-alkanedithiols with palmitic acid or its methyl ester

1- S-Mono-palmitoyl-hexanedithiol and 1- S-mono-palmitoyl-octanedithiol were prepared in high yield (80-90%) by solvent-free lipase-catalyzed thioesterification of palmitic acid with the corresponding alpha,omega-alkanedithiols in vacuo. Similarly, 1,6-di- S-palmitoyl-hexanedithiol and 1,8-di- S-palmitoyl-octanedithiol were prepared in moderate yield (50-60%) by solvent-free lipase-catalyzed thioesterification of palmitic acid with 1- S-Mono-palmitoyl-hexanedithiol and 1- S-mono-palmitoyl-octanedithiol, respectively. An immobilized lipase preparation from Rhizomucor miehei (Lipozyme RM IM) was more effective than a lipase B preparation from Candida antarctica (Novozym 435) or a lipase preparation from Thermomyces lanuginosus (Lipozyme TL IM). Lipase-catalyzed transthioesterifications of methyl palmitate with alpha,omega-alkanedithiols using the same enzymes were less effective than thioesterification for the preparation of the corresponding 1- S-mono-palmitoyl thioesters.

[Controlled inhalation of beta2-sympaticomimetica after bronchial provocation]

The results of several studies indicate that controlling the breathing pattern (inhaled volume and flow rate) during inhalation increases the efficacy of drug delivery to the lungs. By inhaling slowly, deeply and under controlled conditions, intrapulmonary deposition of aerosol and its reproducibility can be increased. However, it has not yet been proven that such inhalations are well tolerated by patients, especially those with airway obstructions. In this study 12 patients with mild asthma underwent a bronchial provocation test. The following broncholysis was performed with controlled, slow, and deep inhalation using the AKITA-device. The patients were asked about the convenience of this inhalation using a questionnaire. In 80 % the controlled inhalation was judged as convenient, neither as too slow nor as too fast, neither as too deep nor as too shallow. Thus it turned out that controlled deep and slow inhalations are convenient even for patients with mild airway obstruction.

[Pulmonary infiltrates with blood eosinophilia in a 62-year-old patient]

A 62-year-old woman was admitted because of chronic cough and bilateral infiltrates on chest roentgenogram. Additional history revealed that the patient had been taken diclofenac emulgel during the previous 10 years for arthrosis. Diagnostic bronchoscopy showed eosinophilic alveolitis. After ruling out infectious, parasitic or systemic diseases drug-induced eosinophilic pneumonia was diagnosed due to topical diclofenac therapy and subsequent percutaneous drug absorption. No previous case of eosinophilic pneumonia to topical diclofenac was discovered in our review of the literature. The diclofenac therapy was discontinued. Oral corticosteroid therapy cleared bilateral infiltrates on CT scan within seven days. Drug reactions are the most common cause of pulmonary infiltrates with blood eosinophilia and/or eosinophilic alveolitis and should be considered as a differential diagnosis.

Peripheral deposition of alpha1-protease inhibitor using commercial inhalation devices

Patients with hereditary alpha1-proteinase inhibitor (alpha1-PI) deficiency are at risk of developing lung emphysema. To prevent the development of this disease, alpha1-PI replacement therapy via inhalation may be a more convenient and effective therapy than the intravenous administration of the drug. In order to optimise this treatment approach, lung deposition of inhaled radiolabelled alpha1-PI (Prolastin) was studied using four different commercial inhalation devices (PARI-LC Star, HaloLite, and AKITA system in combination with LC Star and Sidestream) in six patients with alpha1-PI deficiency and mild-to-severe chronic obstructive pulmonary disease. The time required to deposit 50 mg of the Prolastin (5% solution) in the lung periphery was used as a measure for the efficiency of delivery. The time was calculated from measurements of total and peripheral lung deposition of the radiolabelled alpha1-PI. This time was shortest for the AKITA system (18-24 min) and significantly higher for the PARI-LC Star (44 min) and the HaloLite (100 min). The higher efficiency of drug delivery using the AKITA system is due to the fact that this device controls breathing patterns, which are optimised for each patient individually.

[Difficulties in controlled inhalation of alpha 1-protease inhibitor]

In this paper a number of studies will be summarized which were designed to improve the inhalation of alpha 1 -protease inhibitor in patients with alpha 1-protease inhibitor deficiency. A pilot study has shown that the high inter-individual variability of drug deposition in the lungs is due to heterogeneous breathing patterns of the patients. Controlling the breathing pattern led to a significantly decreased variability. Then it was studied which particle size and breathing pattern resulted in highest peripheral lung deposition in patients with emphysema. It was found that for 3 - 4 microm particles and slow inhalation flow rate the peripheral deposition increases with increasing inhalation volume. After the development of an inhalation device which allows to perform controlled inhalations in clinical practice it was shown that this device, in combination with a breathing pattern individually normalized to the patients lung function, allows to deposit nearly 60 % of the drug into the patients lung periphery.