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971.
Mazur G Wróbel T Dziegiel P Jeleń M Kuliczkowski K Zabel M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2004,42(4):241-243
Angiogenesis is important in development, maintenance and progression of haematological malignancies. Some clinical observations have indicated that in non-Hodgkin's lymphoma (nHL) tumour microvessel density (MVD) may correlate with tumour staging and outcome. The aim of the study was to examine relationship between MVD as a parameter of tumour angiogenesis measured by expression of CD34 and the grade of nHL histological malignancy as determined by REAL classification. 40 lymph node samples of patients with newly diagnosed nHL (17 women, 23 men; aged 48-70 yrs, median age 64 yrs; stage III and IV) and treated at the Department of Haematology, Wroc?aw Medical University in 1999-2002 were fixed in 10% buffered formalin and embedded in paraffin. In all the studied cases, sections were incubated with antibodies against CD34. The slides were stained with hematoxylin and eosin and evaluated histopathologically. Patients were divided into two groups according to histological malignancy: indolent nHL (19 patients) and aggressive nHL (21 patients). Mean MVD measured by expression of CD34 in aggressive and indolent nHL groups amounted to 19.45 +/- 11.24 vessels/0.375 mm2 and 21.7 +/- 12.4 vessels/0.375 mm2, respectively. Statistical analysis of microvessel staining demonstrated no correlation between tumour MVD and grade of histological malignancy in lymph nodes of nHL patients. Nevertheless, angiogenesis observed in nHL provides rationale for use of angiogenesis inhibitors in lymphoma therapy. 相似文献
972.
Dorota?Sanocka Maciej?KurpiszEmail author 《Reproductive biology and endocrinology : RB&E》2004,2(1):12
There is a dynamic interplay between pro- and anti-oxidant substances in human ejaculate. Excessive reactive oxygen species
(ROS) generation can overwhelm protective mechanism and initiate changes in lipid and/or protein layers of sperm plasma membranes.
Additionally, changes in DNA can be induced. The essential steps of lipid peroxidation have been listed as well as antioxidant
substances of semen. A variety of detection techniques of lipid peroxidation have been summarized together with the lipid
components of sperm membranes that can be subjected to stress. It is unsolved, a threshold for ROS levels that may induce
functional sperm ability or may lead to male infertility. 相似文献
973.
Cierpucha M Solecka J Frelek J Szczukiewicz P Chmielewski M 《Bioorganic & medicinal chemistry》2004,12(2):405-416
The [2+2]cycloaddition of chlorosulfonyl isocyanate to simple vinyl ethers derived from the 2-O-sulfonylated (R) and (S) 1-phenyl-1,2-ethanediol leads to 4-alkoxy-azetidin-2-ones with a moderate stereoselectivity. The cycloaddition to analogous (Z)-propenyl ethers proceeds stereospecifically with the retention of the olefin configuration. The intramolecular alkylation of beta-lactam nitrogen atom furnished all possible stereoisomers of 3-phenyl- and 6-methyl-3-phenyl-clavams. The biological and chiroptical activity of synthesized clavams was investigated. The (3R,5R)-diastereomer 30 showed higher inhibition of bacterial enzymes than other related compounds. 相似文献
974.
Adamczyk M Fino JR Mattingly PG Moore JA Pan Y 《Bioorganic & medicinal chemistry letters》2004,14(9):2313-2317
N(10)-Trifluoroacetylpteroic acid was conjugated to chemiluminescent N-sulfonylacridinium-9-carboxamide labels at the N(10) or 9-position carboxamide. Upon binding to folate binding protein the light output of the N(10) derivative (9) was quenched up to 62% upon triggering with basic peroxide, while the 9-position carboxamide conjugate (7) was quenched only 12%. The utility of this effect was demonstrated in a model homogeneous chemiluminescent assay for folic acid. 相似文献
975.
Skoracki M 《Systematic parasitology》2005,60(2):155-158
Neoperisterophila regiusi n. g., n. sp. is described from the quills of Cicinnurus regius (L.) (Passeriformes: Paradisaeidae) from New Guinea. This new genus belongs to the Peristerophila generic group. It differs from other four genera of this group, Peristerophila Kethley, 1970, PsittaciphilusFain et al., 2000, Castosyringophilus Bochkov & Perez, 2002 and Terratosyringophilus Bochkov & Perez, 2002 by the absence of the propodosomal and hysterosomal shields in the females. 相似文献
976.
Korzeniewska M Kołomecki K Stepień H Naze M Stepień T Kuzdak K 《Endokrynologia Polska》2005,56(1):39-44
INTRODUCTION: The growth and persistence of solid tumors and their metastases is connected with angiogenesis. This process is determined by activity of pro- and antyangiogenic factors. VEGF is the one of the most important factors having a stimulant effect on angiogenesis. Soluble forms of VEGF receptors are inhibitors of angiogenesis. The soluble forms of VEGF receptors containing extra cellular part of receptor, which binds ligand, seem to be real inhibitors of VEGF. THE AIM OF THE STUDY: Evaluation the value of serum VEGF and soluble forms of VEGF receptors concentration as a marker of malignancy in patients with hormonal inactive adrenal tumors. MATERIAL AND METHODS: Twenty seven patients (18 female, 9 male; mean age 48+/-4.3 years) with adrenocortical carcinoma (N=8), adrenal metastases (N=4) and adrenocortical adenoma (N=15) were included in this study. Age- and gender-matched control samples were acquired from healthy volunteers (N=10). Serum VEGF and sVEGFR levels were determinated by means of ELISA assay. Statistical analysis was performed using the Student-t test, the Pearson's test and the series test. RESULTS: In healthy controls mean VEGF level was 197.2 pg/ml, sVEGFR-1 43.5 pg/ml and sVEGFR-2 8976.3 pg/ml. Patients with adrenocortical carcinoma had the levels of VEGF (1263.8 pg/ml) significantly higher and of sVEGFR-2 (5893.7 pg/ml) significantly lower in comparison to control group (p<0.05). On the other hand the mean VEGF (334.2 pg/ml) concentration in patients with benign adrenocortical adenoma wasn't significant different than in control group (p>0.05) but mean sVEGFR-1 (21.7 pg/ml) and sVEGFR-2 (7106.4 pg/ml) concentrations were significantly lower than in the control (p<0.05). In metastases group mean VEGF (485.9 pg/ml) level was higher and sVEGFR-2 (5455.2 pg/ml) was lower than in control group (p<0.05). CONCLUSION: These data suggest that determination of VEGF and sVEGFR concentration in the serum of patients with hormonal inactive adrenal tumors may be applied as an additional marker of malignancy. 相似文献
977.
The pH-driven opening and closure of beta-lactoglobulin EF loop, acting as a lid and closing the internal cavity of the protein, has been studied by molecular dynamics (MD) simulations and free energy calculations based on molecular mechanics/Poisson-Boltzmann (PB) solvent-accessible surface area (MM/PBSA) methodology. The forms above and below the transition pH differ presumably only in the protonation state of residue Glu89. MM/PBSA calculations are able to reproduce qualitatively the thermodynamics of the transition. The analysis of MD simulations using a combination of MM/PBSA methodology and the colony energy approach is able to highlight the driving forces implied in the transition. The analysis suggests that global rearrangements take place before the equilibrium local conformation is reached. This conclusion may bear general relevance to conformational transitions in all lipocalins and proteins in general. 相似文献
978.
Free energy differences of binding of adenosine triphosphate (ATP) and guanine triphosphate (GTP) to the protein kinase CK2 (casein kinase 2) were calculated, using molecular dynamics (MD) simulations and the thermodynamic cycle approach. Good agreement with experimental data was obtained. Simulations confirm observations based on crystallographic data that specifically interacting water molecules in the binding site region of CK2 kinase play a key role in its ability to use ATP or GTP as equally efficient phosphate donors. We point out that to obtain quantitatively reasonable results, it was necessary to modify original X-ray data by assuming the presence of an additional water molecule in the CK2 binding site structure with GTP. 相似文献
979.
Oligomerization of human cystatin C (HCC) leads to amyloid deposits in brain arteries, and this process is greatly accelerated with a naturally occurring L68Q variant. The crystal structures of N-truncated and full-length HCC (cubic form) showed dimer formation via three-dimensional (3D) domain swapping, and this observation has led to the suggestion that an analogous domain-swapping mechanism, but propagated in an open-ended fashion, could be the basis of HCC fibril formation. Here we report that full-length HCC, when crystallized in a new, tetragonal form, dimerizes by swapping the same secondary structure elements but with a very different overall structure generated by the flexibility of the hinge linking the moveable elements. The beta-strands of the beta-cores of the two folding units of the present dimer are roughly parallel, while they formed an angle of about 100 degrees in the previous two structures. The dimers pack around a crystallographic dyad by extending their molecular beta-sheets in an intermolecular context. At the other edge of the molecular beta-sheet, side-chain-side-chain hydrogen bonds propagate the beta-structure in the same direction. In consequence, a supramolecular crystal structure is generated, with all the beta-strands of the domain-swapped dimers being perpendicular to one crystallographic direction. This observation is relevant to amyloid aggregation of HCC, as X-ray diffraction studies of amyloid fibrils show them to have ordered, repeating structure, consistent with the so-called cross-beta structure, in which extended polypeptide chains are perpendicular to the fiber axis and form infinite beta-sheets that are parallel to this axis. 相似文献
980.
Batch and continuous mode degradation of monochloroacetic acid used as a sole carbon and energy source in the concentration range of 0.9–48.4 mM by pure culture of Xanthobacter autotrophicusGJ10 was investigated. The substrate was completely degraded in each flask in batch system. Partial substrate inhibition occurred at the concentrations exceeding 25.4mM. Temporary accumulation of glycolic acid in the medium indicated that dehalogenation was undergoing faster than further utilization of glycolate. Three different carbon substrates were used for inoculum preparation – 1,2-dichloroethane, tri-sodium citrate and a nutrient broth. The fastest growth on monochloroacetate occurred for 1,2- dichloroethane-grown inoculum. The assays of haloacid dehalogenase in crude extract indicated that the bacteria grown on 1,2-dichloroethane possessed higher level of the enzyme. The response of the GJ10 culture towards spikes of 20mM monochloroacetate was tested in 2.5-l continuously stirred tank fermentor. The substrate was readily utilized within 7–8h. Continuous degradation of monochloroacetate in the fermentor was demonstrated for monochloroacetate concentration of 20mM and dilution rate 0.016 h–1. Quantitative agreement between the amount of monochloroacetate introduced and chloride released was found. The results demonstrated that the strain X. autotrophicus GJ10 might be suitable for biodegradation of monochloroacetate contaminated media. 相似文献