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991.
JF Taylor A Eggen A Aleyasin SM Armitage W Barendse JE Beever MD Bishop RA Brenneman BM Burns SK Davis K Elo B Harlizius SM Kappes JW Keele SJ Kemp BW Kirkpatrick HA Lewin RZ Ma RA McGraw D Pomp RT Stone Y Sugimoto AJ Teale D Vaiman MC Zanotti 《Canadian Metallurgical Quarterly》1998,29(3):228-235
Allergic bronchopulmonary aspergillosis (ABPA), occurring primarily in patients with asthma or cystic fibrosis (CF), is a hypersensitivity reaction to Aspergillus fumigatus (Af), and is characterized by increased serum IgE levels and peripheral blood and pulmonary eosinophilia. We evaluated the IgE and cytokine profile in ABPA through enzyme-linked immunosorbent assay (ELISA), and evaluated eosinophil activity with the eosinophil peroxidase (EPO) assay. IgE and cytokines were measured in supernatants from cultures of peripheral blood mononuclear cells (PBMC) from three subject groups: ABPA patients, patients with asthma, and healthy individuals. All cultures for the three subject groups were studied in the presence and absence of two purified Af antigens (the 35-kD antigen and heat shock protein 1). We found that increased in vitro levels of IgE in unstimulated PBMC culture supernatants correlated significantly with serum IgE concentrations in ABPA patients. We measured a decrease in IgE levels of up to 75% of baseline values in supernatants from PBMC cultured with Af antigens. Interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) concentrations in cultures with Af were increased in ABPA, whereas concentrations of IL-4 did not differ in the three subject groups. An inverse relation was noted between the changes in IgE and IFN-gamma measured in 4 of 5 ABPA patients. The PBMC supernatants also promoted EPO activity in purified eosinophils from ABPA patients, and to a lesser extent in purified eosinophils from healthy subjects. These results show that the 35-kD antigen and HSP1 from Af downregulate IgE in vitro but are capable of inducing eosinophilia in ABPA. Further studies could result in the characterization of epitopes leading to these disparate effects. An identification of the IgE-down-regulating epitopes in Af antigens might have therapeutic significance. 相似文献
992.
We studied the effect of gastrin-17 on lower esophageal sphincter (LES) characteristics in man. Nine healthy volunteers participated in two experiments performed in random order during continuous infusion of saline (control) or gastrin-17 (15 pmol/kg/hr). LES pressure (LESP) and transient lower esophageal sphincter relaxations (TLESR), as most the important reflux mechanism, were measured with intraesophageal sleeve manometry combined with pH metry. Infusion of gastrin-17 resulted in plasma gastrin levels comparable to those reached after a mixed meal. During continuous gastrin infusion, LESP decreased significantly (P < 0.05) compared to control. The rate and duration of TLESR was not influenced by gastrin-17. Gastroesophageal reflux and the number of TLESR associated with reflux were significantly (P < 0.05) increased during gastrin infusion. These results suggest that in humans gastrin at physiological postprandial plasma concentrations decreases LESP, does not influence TLESR, but increases the percentage of TLESR associated with reflux. 相似文献
993.
Ambient light controls the development and physiology of plants. The Arabidopsis thaliana photoreceptor phytochrome B (PHYB) regulates developmental light responses at both seedling and adult stages. To identify genes that mediate control of development by light, we screened for suppressors of the long hypocotyl phenotype caused by a phyB mutation. Genetic analyses show that the shy (short hypocotyl) mutations we have isolated fall in several loci. Phenotypes of the mutants suggest that some of the genes identified have functions in control of light responses. Other loci specifically affect cell elongation or expansion. 相似文献
994.
S Lee SY Chong JW Lee SC Kim YH Min JS Hahn YW Ko 《Canadian Metallurgical Quarterly》1997,20(10):883-888
Acute graft-versus-host disease (aGVHD) remains a major barrier to a wider application of allogeneic bone marrow transplantation (BMT). Although this complication is mainly dependent on donor-derived T lymphocytes, very little information is available concerning the mechanism of lethality. In this study, we investigated both the expression of Fas/Fas-ligand (FasL) and lymphocyte subset reconstitution in patients who underwent HLA-matched related allogeneic BMT (n = 16) and normal donors (n = 10), and several distinct features were observed. First, the reconstitutions of CD3+ and CD56+ cells were different between the aGVHD+ and aGVHD- group. In particular, the percentage of CD3-CD56+ cells was significantly decreased in patients with aGVHD (P < 0.01). Second, the expansion of CD8+ (P = 0.01) and CD8+ CD28- T cells (P = 0.03) was a characteristic finding in patients with aGVHD. Finally, we found that the percentages of Fas+CD8+, Fas+HLA-DR+ and FasL+ CD8+ cells were significantly increased. Fas antigen was highly coexpressed on most of the lymphocyte subsets, especially on CD8+ cells (P < 0.01), and also, significantly higher coexpression of FasL on CD8+ cells was found in patients with aGVHD (P < 0.01). In summary, an increase in the percentage of CD8+ cells which express Fas and its ligand in patients with aGVHD after BMT points to a possible role for the Fas/FasL pathway in the effector phase of aGVHD. 相似文献
995.
WF Carroll TC Berger FE Borrelli PJ Garrity RA Jacobs JW Lewis RL McCreedy DR Tuhovak AF Weston 《Canadian Metallurgical Quarterly》1998,37(9-12):1957-1972
Under the auspices of its Dioxin Characterization Program, members of The Vinyl Institute (VI), have analyzed for potential polychlorinated dibenzodioxin/furan (PCDD/F) concentrations in polyvinylchloride (PVC) resins, treated wastewater effluent and ethylene dichloride (EDC) product at EDC, vinyl chloride monomer (VCM) and PVC manufacturing facilities in the U.S. and Canada. No 2,3,7,8-tetrachlorodibenzodioxin (TCDD) was detected in any sample analyzed under the program to date. Trace concentrations (low pg/g) of PCDD/F were detected in only a few samples of PVC resins and EDC product. Treated wastewater contained low ppq concentrations of PCDD/F. All concentrations are expressed as Toxic Equivalents (TEQ). Extrapolation of these data shows that the contribution of EDC/VCM/PVC manufacturing via these media constitutes substantially less than 1 percent of the estimated annual U.S. dioxin releases to the environment. 相似文献
996.
997.
PURPOSE: To determine the two-phase (hepatic arterial phase [HAP] and portal venous phase [PVP]) spiral computed tomographic (CT) findings of a nontumorous arterioportal shunt in the cirrhotic liver that can mimic a hypervascular tumor. MATERIALS AND METHODS: For 14 months, 803 patients with known or suspected hepatocellular carcinoma were referred for initial or repeated transcatheter arterial chemoembolization (TACE). Twenty-nine hyperattenuating lesions on HAP CT images obtained in 25 patients (23 men, two women; age range, 39-70 years) were regarded as nontumorous arterioportal shunts and were included in this study. The diagnosis of nontumorous arterioportal shunt was established by four radiologists who reviewed the two-phase spiral CT images and hepatic angiograms. RESULTS: The longest dimension of the lesion was 1.0-7.9 cm (mean dimension, 2.9 cm). The morphology at HAP CT was wedge-shaped in 25 (86%), geographic (ie, focal area with irregular outline) in two (7%), and nodular in two (7%) lesions. All lesions were homogeneous in attenuation. Hyperattenuating linear branching structures that represented early opacification of portal veins were demonstrated during the HAP in nine (31%) lesions. PVP CT images showed these lesions as isoattenuating (n = 20 [69%]) or slightly hyperattenuating (n = 9 [31%]). Iodized oil CT images showed faint or no accumulation of iodized oil in all lesions. CONCLUSION: In cirrhotic liver, nontumorous arterioportal shunts can be a cause of pseudolesions that mimic hypervascular tumors at two-phase spiral CT. Lesions that have the typical wedge-shaped and homogeneous appearance with or without internal linear branching structures during the HAP and that are isoattenuating or slightly hyperattenuating during the PVP can suggest this unusual condition. 相似文献
998.
999.
Various factors influencing the plasma protein binding of YH-439 to 4% human serum albumin (HSA) were evaluated using the equilibrium dialysis method at the initial YH-439 concentration of 2 micrograms mL-1. It took approximately 12 h of incubation to reach an equilibrium between 4% HSA and isotonic phosphate buffer of pH 7.4 containing 3% of dextran ('the buffer') using a Spectra/Por 2 membrane (molecular weight cut-off, 12,000-14,000) in a water bath shaker kept at 37 degrees C and at a rate of 50 oscillations min-1. YH-439 was fairly stable both in 4% HSA and in the 'buffer' for up to 24 h incubation. The binding of YH-439 to 4% HSA was constant (97.4 +/- 0.55%) at YH-439 concentrations ranging from 0.5 to 10 micrograms mL-1. However, the extent of binding was dependent on HSA concentrations: the values were 90.7, 94.7, 96.7, 97.0, 97.0, 97.1, and 97.5% at HSA concentrations of 0.5, 1, 2, 3, 4, 5, and 6%, respectively. The plasma protein binding decreased with increasing incubation temperature: the binding values were 98.2, 97.6, 97.2, and 96.8% when incubated at 10, 21, 26, and 37 degrees C, respectively. The binding of YH-439 was also influenced by the chloride concentration in the buffer: the binding values were 94.5, 97.0, and 96.8% for the chloride concentrations of 0, 0.249, and 0.546%, respectively. The binding of YH-439 was also dependent on the buffer pH: the percentages of free fraction were 6.0, 4.1, 3.8, 2.8, 2.7 and 2.8% for the buffer pHs of 5.0, 6.0, 6.5, 7.0, 7.4, and 8.0, respectively. The free fraction of YH-439 was slightly increased by the addition of heparin (up to 40 U mL-1), sodium azide (NaN3, up to 0.5%), and its metabolites. The protein binding of YH-439 was influenced neither by AAG, acetylsalicylic acid, or sulphisoxazole, nor by the addition of citrate or EDTA. The free fractions of YH-439 in rabbit (4.2%) and dog (4.7%) plasma seemed to be higher than in rats (2.9%) and humans (3.1%). 相似文献
1000.