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11.
We studied the effects of OKY-046 on types II, III and IV allergic reactions, as classified by Coombs and Gell. In Type II, OKY-046 at 30-100 mg/kg intraduodenally (i.d.) and at 1-30 mg/kg intravenously (i.v.) inhibited the bronchoconstriction in a dose-dependent manner after Forssman antigen injection. Aspirin (3 mg/kg, i.v.) also suppressed it. OKY-046 (30-100 mg/kg, i.d.) suppressed the increase of TXB2 level in the plasma in a dose-dependent manner. However, there was no effect of OKY-046 and aspirin on the decrease in complement activity (CH50), platelets and leukocytes. Additionally, OKY-046 (300 mg/kg, p.o.) prolonged the survival time following Forssman antigen injection. However, the immune hemolysis reaction was not prevented by OKY-046 (10(-6)-10(-3) M). FUT-175 protected against the Forssman shock at 1 mg/kg, i.v. and the in vitro immune hemolysis reaction at 10(-5) M. In Type III, OKY-046 (300 mg/kg, p.o.) significantly suppressed the direct passive Arthus reaction and immune complex nephritis in rats. There was no effect of OKY-046 on the delayed-type hypersensitive response to picryl chloride in mice. We think that OKY-046 should be a beneficial drug for the treatment of types II and III allergic reactions.  相似文献   
12.
Two cases of a cavernous angioma with an encapsulated intracerebral hematoma are presented. In both instances, computed tomography scan showed a ringlike appearance with a nodular lesion. Cerebral angiograms of the two cases, however, were normal. The preoperative diagnosis for both cases was a brain neoplasm. The diagnostic problems that this type of vascular malformation presents and its role in the development of the encapsulated hematoma are discussed.  相似文献   
13.
Effects of microwave-induced whole-body hyperthermia (WBH) on the mouse kidney were examined histologically for acute and late effects up to 150 days after WBH treatment at 43.5 degrees C (rectal temperature) for 20 min or 42 degrees C for 40 min. As a whole the damage could be divided into two types. One was the damage to distorted epithelial cells in the subcapsular region. This lesion was common in most animals, possibly caused by direct hyperthermic effect of microwave. The other was general renal atrophy accompanied with aqueous or protein-rich cysts due to a chain of physiological reactions of the whole body to WBH. The first reaction was characterized by general stasis of the blood stream in all parts of the kidney, which resulted in acute ischemia of some tissues. This was seen immediately by dilatation of the renal and interlobular veins as well as the bundles of capillaries in the medulla region. The subsequent event was rather specific cell necrosis of distal and collecting tubular epithelium as compared to proximal tubules. The cell destruction induced cell proliferation of the proximal tubular epithelia after two days. Later on, in accord with the recovery of the blood circulation, the proliferated cells were carried away into the lumen, these processes then resulting in obstruction of tubules through formation of protein casts in the lumen. The block incidentally led to the destruction of nephrons. The degenerated area sometimes consisted of aqueous or protein-rich cysts of various sizes after 7 to 30 days. Thereafter these cysts degenerated, decreasing in both number and size. Thus irreversible atrophy of the kidney developed after WBH.  相似文献   
14.
Two cases underwent a modified Fontan operation with simultaneous superior vena cava-right pulmonary artery end-to-side anastomosis, which we called "bidirectional Glenn shunt". This anastomosis seems to be so effective for reduction of right arterial volume loading, and could proved life-saving in the case with the acute obstruction at the site of the right atriopulmonary artery anastomosis immediately after surgery.  相似文献   
15.
The administration of extracellular, hemoglobin-based oxygen carriers often elicits an acute increase in blood pressure by vasoconstriction. This side effect is now recognized to be due to the depletion of nitric oxide (endothelial-derived relaxing factor) by the extravasuated hemoglobins. We have recently found that the administration of a recombinant human serum albumin (rHSA)-based oxygen carrier involving synthetic tetraphenyporphinatoiron(II) derivative (FeP) (rHSA-FeP) does not induce such hypertensive action, because of its low permeability through the vascular endothelium. The heart rate responses after the rHSA-FeP injection were also negligibly small. Visualization of the intestinal microcirculatory changes clearly revealed the widths of the venule and arteriole to be fairly constant. The entirely synthetic rHSA-FeP becomes a promising material as a new type of red blood cell substitute.  相似文献   
16.
Recombinant human serum albumin including 2-[8-[N-(2-methylimidazolyl)]octanoyloxymethyl]-5,10,15,20-tetrakis(alpha,alpha,alpha,alpha-o-pivaloylamino)phenylporphinatoiron(II) (albumin-heme; rHSA-FeP) is a synthetic hemoprotein that has sufficient capability to reversibly bind and release O(2) under physiological conditions (pH 7.3, 37 degrees C) similar to hemoglobin and myoglobin. In order to use this albumin-based O(2) carrier as a new class of red blood cell substitutes, its compatibility with blood cell components carefully was investigated in vitro. After the addition of the rHSA-FeP solution into whole blood at 10, 20, and 44 vol %, the FeP concentration in the plasma phase remained constant for 6 h at 37 degrees C in each group, and no significant time dependence was observed in the numbers of red blood cells, white blood cells, or platelets. The microscopic observations clearly showed that the shapes of the red blood cells had not been deformed during the measurement period. With respect to the blood coagulation parameters (prothrombin time and activated partial thromboplastin time), the coexistence of rHSA-FeP had only a negligibly small influence. Also the blood compatibility under dynamic flow conditions was evaluated using a microchannel array flow analyzer. All these results suggest that the albumin-heme has no effect on the morphology of blood cell components in vitro.  相似文献   
17.
The human ST2 gene can be specifically induced by growth stimulation in fibroblastic cells, and can also be induced by antigen stimulation in Th2 cells. The gene encodes a soluble secreted protein, ST2, and a transmembrane protein, ST2L, which are closely related to the interleukin-1 receptor. To gain insight into the biological roles of the ST2 gene, three monoclonal antibodies (MAbs) against human ST2 gene products were obtained. To obtain these antibodies, immunization was carried out using two different immunogens: purified soluble human ST2 protein (hST2), and COS7 cells, which express the extracellular portion of human ST2L. 2A5 and FB9 MAbs were derived from the immunization with soluble hST2, and HB12 was derived from the COS7 cell immunization. All three antibodies were shown to detect native forms of the human ST2 gene products by immunoprecipitation, flow cytometry, and enzyme-linked immunosorbent assay (ELISA). In the competitive ELISA using biotinylated and nonlabelled MAbs, neither FB9 nor HB12 affected the binding of 2A5 to ST2 gene products. Based on this result, we constructed a sandwich ELISA system using 2A5 and FB9 to measure the concentration of soluble hST2 in sera. The ELISA, combined with the flow cytometry using these antibodies, will be a useful tool for elucidating the functions of human ST2 gene products in individuals.  相似文献   
18.
S Shinka  T Komatsu  Y Dohi    T Amano 《Immunology》1979,37(1):83-90
The cellular basis of the mechanism of immunological tolerance to human gamma-globulin (H gamma G) induced in foetal and neonatal mice by materno-foetal or materno-neonatal transfer after a single injection of tolerogen (deaggregated H gamma G) into the mothers was investigated using a cell transfer system and assays of passive haemagglutinating antibodies and plaque-forming cells to H gamma G. The results demonstrated that B cells are mainly involved in the tolerance induced on the fourteenth day of gestation, whereas inactivation of T cells may account for the tolerance induced on the eighteenth day of gestation and in the neonatal stage. Treatment of the mothers with tolerogen and then anti-H gamma G serum reduced the tolerance induced on the fourteenth day of gestation, but did not affect that induced on the eighteenth day of gestation and in the neonatal stage. Cell transfer experiments showed that B-cell tolerance induced on the fourteenth day of gestation was prevented by passive antibody, while T-cell tolerance induced on the eighteenth day of gestation and in the neonatal stage was not affected by passive antibody. Assay of the anti-DNP antibody response after immunization with DNP10-H gamma G showed that treatment of mice with the tolerogen on the eighteenth day of gestation, but not the fourteenth day of gestation, inactivated H gamma G-reactive helper cells. The significance of these results is discussed in relation to the results of the cell transfer experiments described as above.  相似文献   
19.
Summary Murine monoclonal antibodies against the fusion (F) and hemagglutininneuraminidase (HN) proteins of Sendai virus (SV) were prepared and studied on their antiviral activities, particularly on the neutralization of infectivity. On the analysis with solid phase competitive ELISA, 26 anti-HN antibodies were divided into at least four groups (HN-I, -II, -III and -IV). Antigenic sites recognized by the HN-I, -II, and -III group antibodies topographically separate from each other. Sites recognized by the HN-IV group antibodies overlaps partially with ones recognized by the HN-I, HN-II and -III group antibodies. The antibodies belonging to the HN-III group highly neutralize the infectivity of SV and weakly or not at all inhibit the hemagglutination (HA). In contrast, the HN-IV group antibodies strongly inhibit HA, but weakly neutralize the infectivity. Adsorption of SV to chicken red blood cells or L cells is inhibited by the HN-IV antibodies, but scarcely by the HN-III antibodies. On the other hand, incubation with HN-III antibodies of HeLa cells that have been preadsorbed with SV at 4° C, followed by culture at 37° C, causes inhibition of infection, but the HN-IV antibodies do not effectively interfere with such infection.The competitive ELISA showed that 17 anti-F antibodies were divided into two groups (F-I and -II). Two antigenic sites recognized by the antibodies, however, seem to be near to each other because a certain competition is observed between the antibodies of both groups. Two of the seven antibodies belonging to the F-II group inhibit the hemolysis activity and also neutralize the infectivity of SV, but the other five F-II antibodies do not. One of the anti-F antibodies has a low HI activity, and, in competition tests, competes with one of the anti-HN antibodies (HN-IV).With 2 Figures  相似文献   
20.
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