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141.
Characterization of the human placental membrane receptor for human 125I-IgG is described. The receptor bound specifically both monomers and aggregates of human IgG. Human colostral IgA, bovine, sheep, pig, and horse IgG were not bound. No effect of pH in the range 6.6–7.4, ionic strength in the range 0.1–0.5, and temperature between 4 and 45°C on the binding was found. A water-soluble fraction containing the active receptor (glycoprotein fraction-PGP) was obtained from the placental membranes using lithium diiodosalicylate. The solubilized receptor interacted with IgG better at 4°C than at 20°C or 37°C. The results on replacement of monomeric IgG by aggregated IgG, and vice versa, suggest that both monomers and aggregates of human IgG, were bound to the same receptor sites. The apparent association constant for monomeric human IgG was 0.86 ± 0.2 × 107 mole?1, and 2.0 ± 0.16 × 1015 IgG molecules were bound per l mg of the membrane protein. Formaldehyde (0.1%), 2-mercaptoethanol (50 mM), and periodate (4 mM) showed no effect on the binding properties of the membrane-bound and on the solubilized receptor, as well. Higher concentrations of periodate (10 mM or 20 mM) decreased the binding of IgG to membranes but showed no effect on the water-soluble receptor. Both the membrane-bound and the solubilized receptor were sensitive to papain. Pronose abolished the receptor activity after prolonged proteolysis only. Neuraminidase did not affect the activity of the receptor. The decrease of the binding activity of the membrane-bound receptor by trypsin and phospholipase C was due to a release of a material containing an active receptor. No effect of trypsin or phospholipase C on the activity of solubilized receptor was observed. The results obtained suggest a protein character of the placental Fc receptor. After electrophoresis of 125I-labeled solubilized receptor in polyacrylamide gel in the presence of SDS, 2 major protein peaks with molecular weights of 74,000 and 104,000 and 3 minor peaks with molecular weights of 56,000, 144,000, and 163,000 were found.  相似文献   
142.
Objective and Design: The myeloperoxidase system of neutrophils generates chlorinating and brominating oxidants in vivo. The major haloamines of the system are taurine chloramine (TauCl) and taurine bromamine (TauBr). It has been demonstrated in vitro that TauCl exerts both antiinflammatory and anti-bacterial properties. Much less is known about TauBr. The present study was conducted to compare bactericidal and immunoregulatory capacity of TauBr with that of the major chlorinating oxidants: HOCl and TauCl. Moreover, the effect of nitrites and H2O2 on TauBr activity was investigated.Materials: TauBr was prepared by reaction of HOBr with taurine. The reaction was monitored by UV absorption spectra.Methods: Bactericidal activity of TauBr, TauCl and HOCl was tested by incubation of E. coli with the compounds and determined by the pour-plate method. To test the anti-inflammatory activity the compounds were incubated with LPS and IFN- stimulated murine peritoneal macrophages. The production of following mediators was measured: nitrites by Griess reaction; TNF-, IL-6, IL-10, IL-12p40 using capture ELISA. In some experiments the compounds were incubated with either nitrites or H2O2.Results: In our experimental set-up TauBr and HOCl exerted strong bactericidal effects on E. coli (MBC = 110 M and 8 M, respectively), while TauCl (< 1000 M) did not kill test bacteria. However, both, TauBr and TauCl, at noncytotoxic concentrations (< 300 M) inhibited the cytokine and nitric oxide production by macrophages. H2O2 completely abolished the biological activities of TauBr but not those of TauCl. Nitrites did not affect any activity of TauBr or TauCl while they diminished the HOCl mediated bacterial killing.Conclusion: TauBr, despite very low concentration of Br in body fluids, may support TauCl and HOCl in the regulation of inflammatory response and in killing of bacteria by neutrophils. However, TauBr activity in vivo will depend on the presence of H2O2 and possible other mediators of inflammation which can compete with target molecules for TauBr.Received 16 August 2004; returned for revision 16 September 2004; accepted by A. Falus 13 October 2004  相似文献   
143.
We studied pulmonary haemodynamics and nocturnal desaturation in 17 patients with an overlap syndrome (OS), all males, mean age 51.4 +/- 8.3 years, mean BMI 37 +/- 4.2 kg/m2. Diagnosis of COPD was based on pts history, clinical examination, lung function tests and chest radiography. Spirometry showed: FVC 2.7 +/- 0.7 L (59 +/- 16% N), FEV1 1.5 +/- 0.7 L (43 +/- 16% N), FEV1% FVC 54 +/- 13%, Raw 0.58 +/- 0.4 kP.s/L, RV 3.3 +/- 1.2 L (144 +/- 51% N), TLC 6.6 +/- 1.3 L (100 +/- 14% N) and RV% TLC (49.5 +/- 12.1%. Arterial blood gas values were: PaO2 56.9 +/- 9.5 mmHg, PaCO2 46.9 +/- 9.8 mmHg, pH 7.37 +/- 0.05. Mean apnoea/hypopnoea index (AHI) was 63.9 +/- 18.9. Pulmonary haemodynamics at rest (Swan Ganz thermodilution catheter) were: mean pulmonary artery pressure (PAP-SP) 24.2 +/- 7.4 mmHg, mean pulmonary wedge pressure (PW-SP) was 9.1 +/- 7.3 mmHg, cardiac output (CO-SP) was 5.6 +/- 2.3 L/min. and pulmonary vascular resistance (PVR) was 229 +/- 97 dyn.sec.cm-5. During exercise (40 Watts, 7 mins, in 8 pts) PAP rose from 19 +/- 6 mmHg to 41.2 +/- 15.1 mmHg, PW rose from 7.4 +/- 7.2 mmHg to 11 +/- 10.2 mmHg, CO rose from 5.8 +/- 2.7 L/min to 12.7 +/- 2.4 L/min. Overnight pulse oximetry showed: mean oxygen saturation (SaO2 mean) 80.2 +/- 8.5%, minimal saturation (SaO2 min) was 50.7 +/- 19.7%. Time spent in desaturation SaO2 < 90% (T 90) was 76.9 +/- 25.7%. We conclude that pts with OS have resting pulmonary hypertension and elevated PVR. During low grade exercise the rise in PAP was highly abnormal. Statistical analysis showed no correlations between nocturnal SaO2 and diurnal pulmonary haemodynamics data.  相似文献   
144.
Investigations on the reactions of diethylzinc ( 1 ) with resorcinol ( 2 ) and phloroglucinol ( 8 ) were carried out for different mole ratios of the reactants. It was found that the reaction of 1 with 2 at a mole ratio of 1:1 is a two step process. In the first step 1 reacts very rapidly with half of applied 2 yielding di(ethylzinc) resorcinolate ( 6 ), which then reacts slowly with the remaining amount of 2 . It was found that zinc 3-ethylzincoxyphenolate resorcinolate ( 5 ) formed in the second step is an active catalyst of the copolymerization reaction of carbon dioxide with propylene oxide. The reaction of 1 with 8 shows a similar course.  相似文献   
145.
Under optimal saturating conditions at SRBC/lymphocyte ratio 100:1 26 +/- 1.2% of human peripheral blood lymphocytes isolated from defibrinated blood form rosettes without incubation, 48 +/- 1.8% after 1-hour, 68 +/- 1.7% after 2 hours incubation at 4 degrees C. According to this, human peripheral T lymphocytes may be subdivided into at least three fractions on the basis of their affinity to SRBC. We called these fractions AFRC (no incubation), C1 RFC (1-hour incubation in cold after removing ARFC fraction) and C2RFC (2-hour incubation in cold after removing ARFC and C1RFC fractions). All the three fractions may be separated by repeated rosetting followed by Ficoll-Uropoculine gradient centrifugation. The purity and viability of T lymphocytes yielded from particular fractions was high. Effective yield of lymphocytes varied between the particular fractions ranging between 100% (for AFRC) and 30% (for C2RFC).  相似文献   
146.
Association of psoriasis vulgaris with HLA-C is not equally strong in different human populations. It has not yet been studied in Polish patients at DNA level, but only by serology that is inadequate for HLA-C. Therefore, we examined the distribution of HLA-C alleles by means of low resolution PCR-SSP in 102 Polish psoriatics and 123 healthy controls. We have found significantly higher representation of HLA-Cw*06 (odds ratio, 18.73; P(cor)<0.001) and significantly lower representation of HLA-Cw*07 (odds ratio, 0.41; P(cor)<0.038) in patients than in controls. Association of HLA-Cw*06 with psoriasis was even stronger in early age at onset (0-20 years) group: odds ratio, 77.71; P(cor)<0.001. Therefore, our population seems to belong to those with strong association of psoriasis with HLA-Cw*06.  相似文献   
147.
148.
We examined 72 female Wistar rats which were divided into 6 groups. The animals were administered sodium nitrate (V), vitamin E or both compounds at the same time. In order to estimate the interference of nitrates in the presence of vitamin E with the metabolism of rat's liver, we determined the composition and the amount of glycosoaminoglycans (GAGs). It was stated that the total amount of GAGs increased in livers of all rats. Basing on all fractions of the examined GAGs it was determined that the most significant differences between individual groups appeared in the amount of heparane sulphate (HS). The results obtained confirmed the fact of the changes taking place in the picture of liver GAGs in the process of ageing of the examined animals. The results obtained, however, allowed to state the normalising influence of vitamin E on the quantitative composition of GAGs of rats which drank nitrates.  相似文献   
149.
150.
The clinical implications of increased cytokine levels after major surgery remain unclear. In this study, systemic concentration of a spectrum of cytokines, including interleukins IL-6, IL-8, IL-10, IL-1ra, and soluble tumor necrosis factor receptor-I (sTNF-RI) was examined in patients with and without postoperative septic complications following colorectal surgery. Although there were no significant changes in IL-1, TNF-, and IL-8 serum levels during the observation period, there was a significant rise in IL-6, IL-1ra, and sTNF-RI concentrations in the entire group of patients between postoperative day 1 and 14. There were no differences between the group without and with local complications when IL-6, IL-1ra, and IL-10 were examined. The serum levels of sTNF-RI, IL-1ra, and IL-6 were found to be sensitive indicators of the pro- and anti-inflammatory response to the surgical trauma, but only sTNF-RI turned out to be a sensitive early marker of local septic postoperative complications in patients with colorectal carcinoma.  相似文献   
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