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991.
992.
Differential effects of interleukin-1 alpha and interleukin-1 beta on human peripheral blood eosinophils 总被引:1,自引:0,他引:1
Interleukin-1 (IL-1) plays a major role in the response to infection, inflammation, and immunological challenge. Eosinophils participate in the host response to parasitic infection and allergic and hypersensitivity diseases. The role of IL-1 in these disease states has not been extensively explored. We have reported that purified human monocyte derived IL-1 (mIL-1), a mixture of the two IL-1 forms but predominantly consisting of IL-1 beta, modulates eosinophil oxidative metabolism and enzyme secretion. Although the two major species of IL-1 (IL-1 alpha and IL-1 beta) have identical specific activities on T cells, we now report the selective effects of human recombinant IL-1 (hrIL-1) alpha and hrIL-1 beta on eosinophil function. Whereas hrIL-1 beta caused a significant increase in arylsulfatase secretion (235.4 +/- 29% of resting secretion, P less than or equal to .01) and beta- glucuronidase secretion (135.8 +/- 9.6% of resting secretion, P less than or equal to .02) similar to our experience with mIL-1, hrIL-1 alpha had no effect on enzyme secretion. However, a mixture of hrIL-1 alpha and hrIL-1 beta reproduced the ability of mIL-1 to inhibit the oxidative response to suboptimal doses of phorbol myristate acetate (PMA). When eosinophils were separated into subpopulations by density gradients, we found that eosinophil responses to IL-1 differed among the populations. These results suggest that eosinophil subpopulations respond selectively to each form of IL-1. 相似文献
993.
994.
Recent studies have examined the synergistic effects of granulocyte- macrophage colony-stimulating factor (GM-CSF) and hematopoietin-1 (now identified as Interleukin-1, IL-1) on bone marrow colony formation. In the present report, human peripheral blood mononuclear cells (MNCs) were stimulated in vitro with recombinant human GM-CSF (rGM-CSF) and production of IL-1 alpha, IL-1 beta, and tumor necrosis factor (TNF) was measured by specific radioimmunoassays. In the MNCs of 20 individuals, rGM-CSF's ability to induce the three cytokines was variable. Nearly all donors responded to low-dose rGM-CSF (0.02 to 2 ng/mL) with production of TNF, whereas some individuals did not produce IL-1 alpha or IL-1 beta. The MNCs from some subjects stimulated with high-dose rGM-CSF (10 to 80 ng/mL) produced as much cytokine as in response to 10 ng/mL endotoxin. Localization (ie, extracellular or cell- associated cytokine) was specific for the cytokine rather than the stimulus. Indomethacin increased the amount of cytokine produced in response to rGM-CSF for IL-1 beta and TNF but not for IL-1 alpha. In addition, interferon-gamma (INF-gamma) upregulated the amount of TNF induced by rGM-CSF in all donors examined, with variable effect on IL-1 alpha and IL-1 beta. Suboptimal levels of endotoxin incubated with rGM- CSF did not alter the amount of IL-1 produced as compared with cells stimulated with rGM-CSF alone, whereas TNF production showed either no change or a slight decrease in production. These data suggest that GM- CSF may play an important role in the host defense response by stimulating production of these cytokines. 相似文献
995.
Measurement of vitamin B12-binding proteins of plasma. II. Interpretation of patterns in disease 总被引:1,自引:0,他引:1
The technique described in the preceding paper was applied to 12 abnormal sera selected for their increase in one or more B12-binding proteins. Even in the presence of large amounts of R-type binder, the ammonium sulfate technique gave a reliable separation of R binding proteins from TC II. Measurement of the TC II in abnormal sera gave results identical to those obtained by the more standard gel filtration. The R binders of four subjects with myeloproliferative disease were further separated into alpha2-R and alpha1-R. The pattern of B12 binding of polycythemia vera (PV) was an exaggeration of the normal pattern. Binding to alpha2-R was three to four times that to alpha1-R, although the total amounts bound to both were increased. In chronic myelogenous leukemia (CML), both alpha2-R and alpha1-R were also increased, but in contrast to binding in normal sera, alpha1-R predominated. In order to interpret the findings, either whole serum R or alpha1-R and alpha2-R from patients with myeloproliferative disease were subject to isoelectric focusing. Alpha2-R consisted pricipally of components isoelectric at pH 2.9, 3.0, and 3.1. These components were present in only minor amounts in normal serum and were somewhat increased in the serum of PV. These components were very much increased in the serum of CML and predominated. Alpha2-R consisted of those components isoelectric at pH 3.4,3.6, and 4.0. These components predominated in the unsaturated binding capacity of normal sera and that of PV. It was concluded that the division of plasma R binders into alpha1-R and alpha1-R by the technique described provided information useful in the study of myeloproliferative diseases. 相似文献
996.
经心内膜右房线形消融治疗心房颤动的安全性评价 总被引:1,自引:0,他引:1
为探讨经心内膜右房线形消融治疗心房颤动(简称房颤)的安全性,12只犬以乙酰胆碱静脉滴注和(或)电刺激建立房颤模型,观察射频导管消融前、后实验犬的病理生理变化。结果显示:①与消融前相比,消融后窦性心率(150.82±36.71bpmvs163.67±30.99bpm)、窦性P波时限(73.64±16.80msvs69.58±12.14ms)、PR间期(120.73±26.29msvs114.02±19.21ms)、校正窦房结恢复时间(76.25±18.87msvs72.50±11.90ms)、右房压力(0.49±0.06kPavs0.46±0.08kPa)以及血浆心钠素(0.48±0.11ng/mlvs0.50±0.07ng/ml)变化均无显著性差异(P均>0.05)。血清磷酸肌酸激酶于消融后即刻明显升高(525.95±426.49U/Lvs115.27±28.70U/L,P<0.01),但术后14日与消融前相比已无显著性差异(114.02±23.35U/Lvs115.27±28.70U/L,P>0.05)。②4只犬发生并发症,其中1只损伤窦房结,2只发现心脏巨大附壁血栓,另1只术后出现一过性房性早搏、短阵房? 相似文献
997.
An arginine to cysteine amino acid substitution at a critical thrombin cleavage site in a dysfunctional factor VIII molecule 总被引:8,自引:2,他引:8
We have analyzed the factor VIII (FVIII) protein and the nucleotide sequence around two thrombin cleavage sites, at arginine 372 in the FVIII heavy chain and arginine 1689 in the FVIII light chain in a naturally occurring dysfunctional FVIII variant, FVIII Okayama. The patient was a 42-year-old hemophiliac with a FVIII coagulant activity of 0.03 U/mL and a FVIII antigen level of 0.8 U/mL. The patient's FVIII was not thrombin activatable to levels seen in normal plasma. Immunoblotting of partially purified FVIII Okayama and normal FVIII showed that thrombin cleavage of the 92 kilodalton (Kd) heavy chain was impaired in the mutant protein. The patient's genomic DNA was amplified using the polymerase chain reaction with two sets of synthetic oligonucleotide primers spanning amino acid residues 319 to 400 and 1630 to 1720. Sequence analysis of the amplified DNA fragments revealed a cytosine to thymine transition, converting an arginine to a cysteine codon at residue 372. No abnormality was found in the FVIII light chain region analyzed. The patient's hemophilic brother and carrier mother revealed the same mutation. We conclude that the pathogenesis of hemophilia A in this patient is probably due to an arginine to cysteine substitution at a thrombin cleavage site in the FVIII heavy chain. 相似文献
998.
Genetically determined polymorphism of the circulating human breast cancer-associated DF3 antigen 总被引:1,自引:0,他引:1
The murine monoclonal antibody (MAb) DF3 was prepared against a human breast carcinoma. Previous studies have demonstrated that DF3 antigen levels are elevated in plasma of patients with breast cancer. Furthermore, MAb DF3 reacts with circulating glycoproteins of different molecular weights ranging from approximately 300 to 450 kd. The present study demonstrates that plasma DF3 antigen is comprised of at least four moieties with slow (S), intermediate (I), rapid (R) and very rapid (VR) electrophoretic mobilities. The electrophoretic mobility patterns for circulating DF3 antigen differ among individuals. Moreover, DF3 antigen is detectable in urine, and the electrophoretic mobility of the urinary moieties is similar, but not identical, to that in the plasma. Studies in family members suggest that the electrophoretic heterogeneity of plasma DF3 antigen is determined by codominant expression of multiple alleles at a single locus. This locus may code for the core protein of DF3 antigen. These findings thus identify a genetically determined polymorphism of a circulating tumor-associated glycoprotein. 相似文献
999.
Primary sclerosing cholangitis (PSC) is a chronic, cholestatic liver condition characterized by progressive fibrosis and destruction
of the intra-and extrahepatic biliary tree. PSC has a clear association with inflammatory bowel disease and is often progressive,
leading to cirrhosis and end-stage liver failure. For many patients, liver transplantation offers the only hope of long-term
survival. No effective medical treatment exists, and therapy is often aimed at treating complications of the disorder, including
dominant biliary strictures, which may cause symptomatic jaundice, cholangitis, and pruritus. Studies on endoscopic therapy
(eg, biliary dilation and/or stent insertion) have shown favorable results, although most studies have been small, retrospective,
and uncontrolled. Up to 20% of patients with PSC develop cholangiocarcinoma; however, distinguishing between cholangiocarcinoma
and benign strictures can be difficult. Ideally, randomized trials are required to determine the safest and most effective
endoscopic management for symptomatic dominant strictures. 相似文献
1000.