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It is important to evaluate the proliferation of bone marrow cells in several disease conditions and during treatment of patients with for example cytokines. Labelling with bromodeoxyuridine (BrdUrd), immunocytochemical staining with anti-BrdUrd antibody and analysis by flow cytometry provides a reliable and reproducible technique for estimation of the fraction of cells that incorporated BrdUrd into DNA during S-phase. We have compared immediate BrdUrd labelling of unseparated bone marrow cells with the previously used labelling in the laboratory after routine separation of the mononuclear cells. Bone marrow aspirates from seven lymphoma patients without bone marrow involvement were studied with these two methods. We found higher BrdUrd labelling indices (LI) in the mononuclear cells, when cells were labelled immediately. A large variation in LI was found between patients. Our results suggest that ex vivo BrdUrd labelling of bone marrow cells should be performed immediately after aspiration and before separation, because these data are closer to values reported from in vivo labelling with BrdUrd.

(RS)-2-Amino-3-(4-butyl-3-hydroxyisoxazol-5-yl)propionic acid (Bu-HIBO, 6) has previously been shown to be an agonist at (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors and an inhibitor of CaCl2-dependent [3H]-(S)-glutamic acid binding (J. Med. Chem. 1992, 35, 3512-3519). To elucidate the pharmacological significance of this latter binding affinity, which is also shown by quisqualic acid (3) but not by AMPA, we have now resolved Bu-HIBO via diastereomeric salt formation using the diprotected Bu-HIBO derivative 11 and the enantiomers of 1-phenylethylamine (PEA). The absolute stereochemistry of (S)-Bu-HIBO (7) (ee = 99.0%) and (R)-Bu-HIBO (8) (ee > 99.6%) were established by an X-ray crystallographic analysis of compound 15, a salt of (R)-PEA, and diprotected 8. Circular dichroism spectra of 7 and 8 were recorded. Whereas 7 (IC50 = 0.64 microM) and 8 (IC50 = 0.57 microM) were equipotent as inhibitors of CaCl2-dependent [3H]-(S)-glutamic acid binding, neither enantiomer showed significant affinity for the synaptosomal (S)-glutamic acid uptake system(s). AMPA receptor affinity (IC50 = 0.48 microM) and agonism (EC50 = 17 microM) were shown to reside exclusively in the S-enantiomer, 7. Compounds 7 and 8 did not interact detectably with kainic acid or N-methyl-D-aspartic acid (NMDA) receptor sites. Neither 7 nor 8 affected the function of the metabotropic (S)-glutamic acid receptors mGlu2 and mGlu4a, expressed in CHO cells. Compound 8 was shown also to be inactive at mGlu1 alpha, whereas 7 was determined to be a moderately potent antagonist at mGlu1 alpha (Ki = 110 microM) and mGlu5a (Ki = 97 microM). Using the rat cortical wedge preparation, the AMPA receptor agonist effect of 7 was markedly potentiated by coadministration of 8 at 21 degrees C, but not at 2-4 degrees C. These observations together indicate that the potentiation of the AMPA receptor agonism of 7 by 8 is not mediated by metabotropic (S)-glutamate receptors but rather by th

A general strategy for performing energy minimization of proteins using the SYBYL molecular modelling program has been developed. The influence of several variables including energy minimization procedure, solvation, dielectric function and dielectric constant have been investigated in order to develop a general method, which is capable of producing high quality protein structures. Avian pancreatic polypeptide (APP) and bovine pancreatic phospholipase A2 (BP PLA2) were selected for the calculations, because high quality X-ray structures exist and because all classes of secondary structure are represented in the structures. The energy minimized structures were evaluated relative to the corresponding X-ray structures. The overall similarity was checked by calculating RMS distances for all atom positions. Backbone conformation was checked by Ramachandran plots and secondary structure elements evaluated by the length on hydrogen bonds. The dimensions of active site in BP PLA2 is very dependent on electrostatic interactions, due to the presence of the positively charged calcium ion. Thus, the distances between calcium and the calcium-coordinating groups were used as a quality index for this protein. Energy minimized structures of the trimeric PLA2 from Indian cobra (N.n.n. PLA2) were used for assessing the impact of protein-protein interactions. Based on the above mentioned criteria, it could be concluded that using the following conditions: Dielectric constant epsilon = 4 or 20; a distance dependent dielectric function and stepwise energy minimization, it is possible to reproduce X-ray structures very accurately without including explicit solvent molecules.

We compared the effect of 560 mg. estramustine phosphate daily to placebo as a supplement to standard palliative therapy in patients with progressive disease after bilateral orchiectomy as first line therapy for metastatic prostate cancer.

A molecular dynamics (MD)-based conformational analysis has been performed on a number of cycloalkanes in order to demonstrate the reliability and generality of MD as a tool for conformational analysis. MD simulations on cyclohexane and a series of methyl-substituted cyclohexanes were performed at temperatures between 400 and 1200 K. Depending on the simulation temperature, different types of interconversions (twist-boat-twist-boat, twist-boat-chair and chair-chair) could be observed, and the MD simulations demonstrated the expected correlation between simulation temperature and ring inversion barriers. A series of methyl-substituted 1,3-dioxanes were investigated at 1000 K, and the number of chair-chair interconversions could be quantitatively correlated to the experimentally determined ring inversion barrier. Similarly, the distribution of sampled minimum-energy conformations correlated with the energy-derived Boltzmann distribution. The macrocyclic ring system cyclododecane was subjected to an MD simulation at 1000 K and 71 different conformations could be sampled. These conformations were compared with the results of previously reported conformational analyses using stochastic search methods, and the MD method provided 19 out of the 20 most stable conformations found in the MM2 force field. Finally, the general performance of the MD method for conformational analysis is discussed.

Interleukin 4 (Il-4) is an immunoregulatory cytokine which induces T-cell proliferation and differentiation into a Th2 phenotype, and is of particular importance for the induction of IgE synthesis. In the present study, the capability of human peripheral blood eosinophils from allergic and non-allergic donors to produce Il-4 was examined. Using reverse transcribed polymerase chain reaction (RT-PCR), it was shown that highly purified eosinophils from allergic patients express mRNA for Il-4. Resting eosinophils also gave specific immunoreactivity with anti-Il-4 antibodies, consistent with translation of Il-4 mRNA. Light and electron microscopic immunocytochemistry revealed that Il-4 was prestored in the eosinophilic granules. These results were confirmed by Il-4 specific ELISA which showed that Il-4 production could be upregulated in the eosinophils and released from the eosinophils following stimulation with the calcium ionophore A23187. These data indicate that eosinophils may be an important source of Il-4 at sites of allergic inflammation. Thus, eosinophils may act as immunomodulatory cells enhancing the allergic response through formation of Th2-cells and inducing the isotype switching to IgE in human B-cells.

A procedure has been developed for measuring the steady state rate of permeation of commercial solvents through living human skin. To get the most consistent results, it was necessary with some solvents to normalize the solvent permeation rate of a given skin sample with its [3H]water permeation rate. For other solvents this was not necessary, so the un-normalized data were used. High [3H]water permeation rate also was used as a criterion for "defective" skin samples that gave erroneous permeability rates, especially for solvents having slow permeability. The linearity of the steady state data was characterized by calculation of the "percent error of the slope." The following permeability rates (g/m2h) of single solvents were measured: dimethyl sulfoxide (DMSO), 176; N-methyl-2-pyrrolidone, 171; dimethyl acetamide, 107; methyl ethyl ketone, 53; methylene chloride, 24; [3H]water, 14.8; ethanol, 11.3; butyl acetate, 1.6; gamma-butyrolactone, 1.1; toluene, 0.8; propylene carbonate, 0.7; and sulfolane, 0.2. The effect of [3H]water saturation on the shape of the presteady state portion of the permeation curve was determined and found to be very dependent on the solvent. The permeability of mixtures of DMSO and octyl acetate were measured. No octyl acetate was detected and the permeability of DMSO was proportional to its mole fraction in the mixture. The effect of two hours of solvent exposure on the viability of skin (based on DNA synthesis) was measured and found to be very dependent on the solvent.

In 245 patients with previously untreated advanced carcinoma of the prostate, serum concentrations of testosterone have been measured before androgen deprivation therapy, and patients were divided in quartiles according to their serum concentration. Pretreatment level of serum testosterone was confirmed as having significant prognostic value on progression-free, overall, and cancer-specific survival, and the hazard ratios of lower quartiles compared to the upper quartile for these endpoints were 2.3, 2.1, and 2.0, respectively. However, correlations with symptomatology and other pretreatment parameters suggest that low serum testosterone merely is a consequence of the advanced malignancy rather than a causative factor in the pathogenesis of prostatic cancer.

Bromodeoxyuridine (BrdUrd) labelled and unlabelled mitotic cells, respectively, can be discriminated from interphase cells using a new method, based on immunocytochemical staining of BrdUrd and flow cytometric four-parameter analysis of DNA content, BrdUrd incorporation, and forward and orthogonal light scatter. The method was optimized using the human leukemia cell lines HL-60 and K-562. Samples of 10(5) ethanol-fixed cells were treated with pepsin/HCl and stained as a nuclear suspension with anti-BrdUrd antibody, FITC-conjugated secondary antibody, and propidium iodide. Labelled mitoses could be discriminated from unlabelled mitoses, and from labelled and unlabelled G2 cells, by their intermediate log FITC fluorescence intensity. In addition, mitoses and G2 nuclei differed in forward and orthogonal light scattering, but had equal intensity of propidium iodide fluorescence. This method for discrimination of labelled mitoses was also tested on cultured normal adult human keratinocytes labelled with iododeoxyuridine (IdUrd). In keratinocytes, where the cell structure was preserved after pepsin/HCl, IdUrd labelled mitotic cells were similarly discriminated in the log FITC/propidium iodide fluorescence distribution. This interpretation was supported by experiments using mitotic arrest, fluorescence activated cell sorting and microscopy, and comparison with an alternative flow cytometric method for discrimination of mitoses.

Udgivelsesdato: 1994-Nov-1, We investigated the influence of cellular heterogeneity on the response to low-dose BCNU chemotherapy of an artificially mixed human small-cell lung cancer (SCLC) xenograft in nude mice containing a BCNU-sensitive and dominating sub-population and a BCNU-resistant and undetectable (dominated) sub-population. The cell lines differed in DNA content, making them distinguishable by DNA flow cytometry (FCM). After 3 weeks of tumor growth, the mice were stratified according to tumor size and randomized to 2 different low-dose treatments with BCNU or no treatment. After a further 3 to 4 weeks, a high-dose treatment (LD10) was given to both groups of treated tumors. Changes in the relative proportions of and cell lines in the tumors were measured by FCM on fine-needle tumor aspirates. At the time of low-dose treatment, all the tumors were totally dominated by the sensitive cells. A temporary response was seen after low-dose treatment. After the high-dose treatment, a similar short response was seen. In the non-treated group, the sensitive cells continued to dominate. At the time of tumor regrowth after the low-dose treatment, most of the tumors continued to be dominated by the sensitive population. At the time of progression after the response to the high-dose treatment, the resistant cell line was the predominant population. If compared with a single high-dose BCNU treatment, the response of tumors treated with a low dose was superior, indicating that the presence of a dominating and slower growing sub-population influenced the outcome of the treatment.

The present overview of advanced prostate cancer required the identification of randomized clinical trials studying the question of maximal androgen blockade versus the classic castration therapy. The heterogeneity of the trials concerned the type of castration (surgical or chemical) and the type of antiandrogen (flutamide, Anandron, or cyproterone acetate) added to castration. This paper reviews the different types of heterogeneity that might exist among trials that are involved in the overview: study design, randomization procedure, treatment evaluation, statistical evaluation, and data maturity. In order to overcome these various types of heterogeneity and to compare like with like, the treatment comparison should be stratified a posteriori by question (i.e., type of castration or type of anti-androgen studied) and by study. In this way, one may draw valid conclusions. Of course, those trials with a larger number of patients and a longer follow-up will contribute more to the overview's results.

In a multicenter trial conducted by the Danish Prostatic Cancer Group, 264 patients with advanced prostate cancer were randomized either to undergo bilateral orchiectomy or to receive combination treatment with goserelin acetate and flutamide. This report is an update of that study, covering a median follow-up for survival of 57 months. Of 262 patients who were evaluated, 208 have died. As noted in earlier analyses of this study, no differences in time to progression and cause-specific and overall survival could be identified between the two treatment groups. In conclusion, the combination of goserelin and flutamide was not clinically superior to bilateral orchiectomy in the treatment of advanced prostate cancer.

The present overview of advanced prostate cancer required the identification of randomized clinical trials studying the question of maximal androgen blockade versus the classic castration therapy. The heterogeneity of the trials concerned the type of castration (surgical or chemical) and the type of antiandrogen (flutamide, Anandron, or cyproterone acetate) added to castration. This paper reviews the different types of heterogeneity that might exist among trials that are involved in the overview: study design, randomization procedure, treatment evaluation, statistical evaluation, and data maturity. In order to overcome these various types of heterogeneity and to compare like with like, the treatment comparison should be stratified a posteriori by question (i.e., type of castration or type of anti-androgen studied) and by study. In this way, one may draw valid conclusions. Of course, those trials with a larger number of patients and a longer follow-up will contribute more to the overview's results.

Three-dimensional structures of the enzyme phospholipase A2 (PLA2) from human pancreas and from human synovial fluid were constructed by model building based on high-resolution X-ray crystallographic structures and homology considerations. The structure of the human pancreatic PLA2 was based on the X-ray structure of the highly homologous bovine pancreatic PLA2 (Type I) by amino acid substitution and modification of the C-terminal part followed by geometry relaxation. The structure of the PLA2 from human synovial fluid was constructed from the X-ray structure of PLA2 from Crotalus atrox (Type II) by modification of the calcium binding loop, amino acid substitution, and insertion of two additional amino acid residues followed by geometry relaxation. The structure of the two human PLA2's have been compared and their use as targets for rational design of enzyme inhibitors discussed.

3-Hydroxy-4-(2-hydroxyethyl)-5-methylisoxazole (1) was used as the starting material for the syntheses of the muscimol (5-aminomethyl-3-hydroxyisoxazole) analogues 9, 10 and 14, containing 2-acetoxyethyl, 2-hydroxyethyl, and 2-chloroethyl substituents, respectively, in the 4-position of the ring. These analogues were synthesized via bromination of the 5-methyl groups of the di-O-protected derivative of 1 (5) followed by a Gabriel phthalimide reaction. N-Deprotection of 4-(2-chloroethyl)-3-methoxy-5-phthalimidomethylisoxazole (12), an intermediate for the preparation of 14, followed by cyclization and O-deprotection form the last steps of a new synthesis of the clinically active bicyclic muscimol analogue, (4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridin-3-ol) (THIP) (16). Whereas treatment of 4-(2-hydroxyethyl)-3-methoxy-5-methylisoxazole (3a) with bromine or with NBS gave the bicyclic 2-isoxazoline 17a. A similar treatment of the 4-(3-hydroxypropyl) homologue (3b) of 3a did not provide the 6-membered ring analogue of 17a (17b). Whilst muscimol and THIP are very potent agonists at GABA(A) receptors, none of the muscimol analogues 9, 10 or 14 showed significant affinity for GABA(A) receptor sites in vitro.

A total of 591 patients with advanced prostatic cancer have been randomized to either orchiectomy or treatment with zoladex 3.6 mg as a depot preparation combined with flutamide 250 mg tid in two European studies, EORTC protocol 30853 and DAPROCA 86. Identical design and comparable patient characteristics in the two studies have allowed combined analysis. A small but statistically significant difference in time to objective progression or death from prostatic cancer was found in favor of the combination treatment. However, time from objective progression to death was longer in the group initially allocated to orchiectomy. Thus, no difference between treatment groups in overall survival was found. As a conclusion, the combined androgen blockade was not superior to orchiectomy in the treatment of patients with advanced prostatic cancer.

Very often not enough patients are entered and/or the follow-up is insufficient to be able to draw valid conclusions in cancer clinical trials. In this article, we discuss the possibility of pooling the data from two or more trials asking the same or similar questions in order to overcome such problems. How comparable the studies should be for combining their data, in terms of design, patient population, follow-up, and end-points, is discussed in the first part of this paper. Whether these general considerations were completely or partially fulfilled in the two prostatic studies of the EORTC and DAPROCA is the subject of the second part of this article. Problems of interpreting apparently contradictory results, like the superiority of zoladex and flutamide over orchidectomy in terms of time to progression with no clear superiority in terms of overall duration of survival, is also discussed.