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21.
The relationship between malignancy and histamine metabolism in the liver and the small intestine has been examined in sarcoma-bearing Wistar rats two weeks after subcutaneous implantation of a transplantable methylcholanthrene sarcoma Sa1828 and on the 3, 7 and 14th days after tumour extirpation. Two weeks after tumour implantation, the histamine level was increased by 100% and 50% in the liver and the small intestine, respectively. On the 3rd day after extirpation of the tumour the level of histamine had returned to the control values and remained unchanged during the next 10 days. Neither of the histamine catabolizing enzymes, diamine oxidase with a putrescine as a substrate or histamine methyltransferase were influenced by the existing tumour or by its extirpation except on the 14th day where a high increase in diamine oxidase activity was found. Some changes in the distribution of histamine metabolites suggest an involvement of an oxidative pathway of histamine catabolism as well as the aldehyde catabolizing enzymes in tumour development. 相似文献
22.
Zielonka TM Marchel A Pogorzelski R Górska K Safianowska A Byśkiniewicz K Chazan R 《Pneumonologia i alergologia polska》2004,72(9-10):429-432
The authors describe the case of survival for the period of 10 years after brain metastasis surgery and removal of the left lung upper lobe due to adeno-squamous cells carcinoma. Surgery did not generate any complications. Within 8 years after the surgery the radiological examination showed infiltrations resembling changes typical for tuberculosis. Microbiological analysis showed a culture of Mycobacterium kansasi leading to diagnosis of mycobacteriosis. Hence the antituberculous treatment was extended to 12 months to be interrupted due to liver damage. Two years later the patient experienced incident of haemoptysis. Detailed examination and assessment of the respiratory tract condition revealed COPD without features of renewal of the neoplastic process or infection by Mycobacterium tuberculosis or mycobacterium other than tuberculosis. This case demonstrates that aggressive surgical approaches to lung cancer with solitary cerebral metastasis significantly improve patient survival and justifies its widespread use. 相似文献
23.
Howard M Sellors JW Jang D Robinson NJ Fearon M Kaczorowski J Chernesky M 《Journal of clinical microbiology》2003,41(1):84-89
This study estimated the regional and age- and gender-specific seroprevalences of herpes simplex virus type 1 (HSV-1) and HSV-2 in Ontario, Canada. Stored serum specimens from subjects aged 15 to 44 years, including men (n = 979), women not under prenatal care (n = 638), and women under prenatal care (n = 701) submitted for routine viral serology were randomly selected according to regional population size from public health laboratories. HSV-1 and HSV-2 testing was done with the MRL enzyme immunoassay (EIA) (Focus Technologies), and HSV-2 was also tested by the Gull/Meridian EIA. Specimens discordant for HSV-2 antibodies between the two EIAs were resolved by a recombinant immunoblot assay (Focus Technologies). The overall age- and gender-standardized seroprevalences of HSV-1 and HSV-2 were 51.1% (95% confidence interval [CI], 50.1 to 52.1) and 9.1% (95% CI, 8.6 to 9.7), respectively. The seroprevalence of HSV-1 antibodies increased from 26.9 to 54.7% in men between 15 to 16 and 40 to 44 years of age, from 32.0 to 88.7% in women not under prenatal care, and from 55.2 to 69.2% in women under prenatal care. The seroprevalence of HSV-2 increased from 3.8 to 21.3% in men between 15 to 16 and 40 to 44 years of age, from 0 to 18.9% in women not under prenatal care, and from 3.4 to 23.1% in women under prenatal care. HSV-2 results were discordant for 3.3% (76 of 2,318) of specimens. Both types of HSV antibodies appeared to be acquired earlier among women under prenatal care than among men and women not under prenatal care. Antibodies were more prevalent among people in northern Ontario (72.9% of subjects [range, 68.4 to 77.4%] for HSV-1 and 13.7% of subjects [95% CI, 10.2 to 17.2%] for HSV-2) than elsewhere. 相似文献
24.
An inhibition enzyme-linked immunosorbent assay for the detection of antibody to Rift Valley fever virus in humans, domestic and wild ruminants 总被引:2,自引:0,他引:2
This paper describes the development and validation of an inhibition ELISA based on gamma-irradiated tissue culture-derived antigen for the detection of antibody to Rift Valley fever virus (RVFV) in humans, domestic and wild ruminants. Validation data sets derived from field-collected sera in Africa (humans=1367, cattle=649, goats=806, sheep=493, buffalo=258, camels=156) were categorized according to the results of a virus neutralisation test. In addition, individual sera from 93 laboratory workers immunized with inactivated RVF vaccine, 136 serial bleeds from eight sheep experimentally infected with wild-type of RVFV, and 200 serial bleeds from 10 sheep vaccinated with the live-attenuated strain of the virus, were used to study the kinetics of RVFV antibody production under controlled conditions. At cut-off values selected at 95% accuracy level by the two-graph receiver operating characteristic analysis the ELISA sensitivity ranged from 99.47% (humans) to 100% (sheep, buffalo, camels). The specificity ranged from 99.29% (sheep) to 100% (camels). Compared to virus neutralisation and haemagglutination-inhibition tests, the ELISA was more sensitive in detection of the earliest immunological responses in experimentally infected and vaccinated sheep. Our results demonstrate that the ELISA format reported here can be used as a safe, robust and highly accurate diagnostic tool in disease-surveillance and control programmes, import/export veterinary certification, and for monitoring of the immune response in vaccinees. 相似文献
25.
Maciej Bero Janusz Kasperczyk Zbigniew J. Jedlinski 《Macromolecular chemistry and physics.》1990,191(10):2287-2296
Racemic lactide was polymerized with various initiators containing Zn and Al, and the structures of the obtained polymers were determined by means of 13C NMR spectroscopy. The extent of transesterification reactions was calculated on the basis of the analysis of the methine carbon signal in the polymer 13C NMR spectra. Three groups of initiators can be distinguished in view of their influence on transesterification: ZnCl2 exhibits the strongest transesterification activity, ZnEt2 and ZnEt2/Al(OiPr)3 are among those of medium activity, and Al(acac)3 does not show transesterification activity at all. 相似文献
26.
Placenta from an extrauterine abdominal pregnancy was examined after a 37-week healthy infant gestation. The placenta, with its fetal surface down and maternal surface up, protruded from the pelvic area to peritoneal cavity in the wall of the amniotic sac containing fetus. The placenta was implanted under the thin subperitoneal layer of maternal tissue completely covered by peritoneal serosa and was formed by several small lobes connected by intramembranous placental vessels. Insertion of the trivascular umbilical cord was velamentous. Partially remodeled arteries infiltrated by intermediate trophoblast and frequent veins directly communicating with the placental intervillous space were identified in the subperitoneal maternal tissue. The term "placenta accreta" is appropriate in this case because villi in the basal plate implanted directly in the maternal subserosal connective tissue without intervening decidua. 相似文献
27.
Moryś J Berdel B Kowiański P Majak K Tarnawski M Wisniewski HM 《Neuroscience letters》1999,259(2):91-94
Two-laser and two-color approaches were used to observe the colocalization of the calcium-binding proteins, calbindin D28k and parvalbumin, and the retrograde tracer, Fluoro-Gold (FG) in the basolateral amygdala of the rat. The study was performed on five adult rats into which FG was injected to the frontal association cortex. Then, the localization of the retrogradely labeled neurons in the basolateral amygdala was compared with the localization of the neurons labeled by calcium-binding proteins. The present study showed that most of the retrogradely labeled neurons in the posterior part of the basolateral amygdala are also calbindin-positive. Even though a lot of parvalbumin-positive endings were present at the surface of the retrogradely labeled cells, we did not observe the colocalization of the parvalbumin and projective neurons. 相似文献
28.
Małgorzata Niezgódka Joanna Mikulska Maciej Ugorski Janusz Boratyński Józef Lisowski 《Molecular immunology》1981,18(3):163-172
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
29.
J. Marcinkiewicz M. Mak M. Bobek R. Biedroń A. Białecka M. Koprowski E. Kontny W. Maśliński 《Inflammation research》2005,54(1):42-49
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
30.
R Fiedorowicz J Moniuszko-Jakoniuk K Wi?niewski 《Archivum immunologiae et therapiae experimentalis》1983,31(5):739-748
The influence of different doses of bradykinin (2.5 micrograms, 5 micrograms/kg i.v.) and dopamine (0.5 micrograms - a small dose and 25 micrograms, 250 micrograms/kg i.v. - a big dose) administered into the rat femoral artery on the blood pressure was estimated. Dopamine evoked hypotension (the small dose) or hypertension (the big dose). Bradykinin evoked dose-dependent decrease of the blood pressure. Bradykinin (2.5 micrograms/kg i.v.) administered in the 45th sec of the dopamine action enhanced the hypertensive effect and decreased the hypotensive effect of dopamine. Dopamine administered in the big dose after phentolamine and propranolol evoked hypotension. This effect was stronger after administration of dopamine (25 micrograms/kg i.v.). The hypotensive action of bradykinin persisted in spite of phentolamine and propranolol application but this peptide did not change the hypotensive effect of dopamine under these conditions. The authors discuss hypothetical mechanism of action of the observed influence of bradykinin on the effect of dopamine in the circulatory system. 相似文献