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951.
Prevalence of basidiospore allergy in the Pacific Northwest 总被引:3,自引:0,他引:3
Jay D. Sprenger MD Leonard C. Altman MD Carol E. O''Neil PhD Garrison H. Ayers MD Brian T. Butcher PhD Samuel B. Lehrer PhD 《The Journal of allergy and clinical immunology》1988,82(6):1076-1080
Mold spore-induced respiratory allergy has been incompletely studied, and only a limited number of Fungi Imperfecti are well established as aeroallergens. Basidiomycetes, a complex and common group of fungi, which include mushrooms, rusts, smuts, brackets, and puffballs, have not been well studied. Although basidiospores can be present in high atmospheric concentrations, little is known of their aeroallergen potential. To examine this question, we performed skin prick and RASTs in 33 adult residents of Washington State using a panel of 15 common inhalant allergents that included four Fungi Imperfecti and 15 basidiospore extracts. Thirty-one of 33 (94%) subjects had positive immediate reactions to two or more common inhalants. Nine of 33 (27%) subjects responded to at least one Fungi Imperfecti; reactions were most common to Aspergillus sp. (21%), and least common to Penicillium sp., which were positive in 6%. Positive responses to basidiospore extracts were observed in 10 of 33 (30%) subjects. The prevalence of basidiospore reactivity was similar to that of Fungi Imperfecti, ranging from 18% for Scleroderma sp. to 6% for four different spore extracts. These results demonstrate that a significant number of subjects with respiratory allergies have skin test reactivity to basidiospore extracts, suggesting that these spores could be important aeroallergens in the Pacific Northwest. 相似文献
952.
Protein kinase C-activating phorbol esters augment expression of T cell receptor genes 总被引:2,自引:0,他引:2
D J Noonan N Isakov A N Theofilopoulos F J Dixon A Altman 《European journal of immunology》1987,17(6):803-807
Tumor-promoting phorbol esters (PE) can modulate cellular functions and cell surface determinant expression in a variety of cell types, including T lymphocytes, presumably by activating the enzyme, protein kinase C (PKC). To examine whether PKC might be involved in regulating the expression of genes encoding the antigen-specific T cell receptor (TCR), we cultured the murine thymoma line, EL4, in the presence of 12-O-tetradecanoylphorbol 13-acetate (TPA) and analyzed the expression of TCR alpha or beta-chain genes by Northern blots. TPA stimulation of an interleukin 2 (IL 2)-producing variant, EL4+, induced a 3-4-fold increase in TCR beta, but not alpha, chain mRNA. Maximal increase was obtained with 3 ng/ml TPA and 12 h of stimulation. This effect appeared related to PKC activation because other tumor-promoting PE known to be PKC activators, but not inactive PE, induced the same increase. TPA stimulation of EL4+ cells also induced de novo expression of the IL 2 gene and subsequent secretion of this lymphokine. However, the increased expression of the TCR beta-chain gene and the induction of the IL 2 gene were not linked since expression of TCR beta-chain mRNA was increased to a similar degree in EL4+ and IL 2-nonproducing EL4- sublines, and cyclosporin A selectively blocked TPA-induced IL 2-gene expression in EL4+ cells without affecting the increase in TCR beta-chain mRNA. These findings suggest that PKC activation, an event that supposedly occurs after antigen-mediated triggering of the TCR, can regulate the expression of at least some of the genes encoding this receptor. 相似文献
953.
S P Orr J M Claiborn B Altman D F Forgue J B de Jong R K Pitman L R Herz 《Journal of consulting and clinical psychology》1990,58(3):329-335
Three groups of Vietnam combat veterans, posttraumatic stress disorder (PTSD, n = 25), anxious (n = 7), and healthy (n = 18), completed a battery of psychometric tests. Measurement of psychophysiologic responses to imagery of individualized combat experiences followed the psychometrics. The PTSD Ss differed significantly from the healthy Ss on almost all measures but showed fewer differences from the anxious Ss. The typical PTSD S was characterized as anxious, depressed, prone to dissociation, and external in locus of control. Correlations with the physiologic responses supported the validity of psychometric scales specifically designed to measure PTSD but cast doubt on the interpretation of traditional measures of overreporting or dissimulation in this disorder. 相似文献
954.
The paper extends a mathematical model for point-source electrical stimulation of a nerve. In the original model, it was assumed
that all the axons in the nerve have the same diameter. In this paper the model is extended to represent a nerve with an arbitrary
distribution of axon diameters. It is shown that the assumption of identical axons is justified for a typical human nerve
if the ‘representative’ axon diameter is taken as the area-weighted average of the diameter distribution. 相似文献
955.
956.
Phorbol ester synergizes with Ca2+ ionophore in activation of protein kinase C (PKC)alpha and PKC beta isoenzymes in human T cells and in induction of related cellular functions.
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Studies described herein were designed to examine the effects of 12-O-tetradecanoyl phorbol-13-acetate (TPA), and a Ca2+ ionophore (ionomycin), singly or in combination, on the activation and expression of the Ca(2+)-dependent protein kinase C (PKC) isoenzymes (alpha, beta and gamma) at the protein and messenger RNA (mRNA) levels in T cells. These two agents induce the activation and proliferation of T lymphocytes by mimicking the action of inositol phospholipid-derived second messengers normally generated by triggering of the antigen-specific T-cell receptor (TcR)/CD3 complex. TPA-induced T-cell proliferation, expression of interleukin-2 receptor-alpha subunit (IL-2R alpha) and transferrin receptor, CD3 down-regulation and, lastly, the cytosol-to-membrane PKC translocation (determined by an enzymatic assay or by immunoblotting with a cross-reactive anti-PKC peptide antibody) were all facilitated by ionomycin. Immunoblots with isoenzyme-specific anti-PKC monoclonal antibodies demonstrated expression of immunoreactive PKC alpha, PKC beta and PKC gamma proteins that were translocated to the membrane upon TPA plus ionomycin stimulation. Resting T cells expressed abundant levels of mRNA for PKC alpha and PKC beta, but very low levels (relative to brain) of PKC gamma. TPA increased by two- to threefold the expression of PKC beta, but not of PKC alpha or PKC gamma, mRNA within 12 hr of stimulation. Ionomycin synergized with TPA in increasing the expression of PKC alpha and PKC beta mRNA. The two agents also synergized in inducing expression of additional activation/growth-associated genes, namely the c-myc protooncogene, ornithine decarboxylase (ODC) and IL-2R alpha. Ionomycin alone was inactive (or marginally active) in all of these assays. The translocation of distinct Ca(2+)-dependent PKC isoenzymes to the membrane and the up-regulation of PKC alpha and beta mRNA suggest that at least these two isoenzymes are involved in discrete steps of the pathway leading to T-cell activation and proliferation. Moreover, the combined effects of TPA and ionomycin on T-cell function and cell-surface antigen expression appear to be due, at least in part, to their synergistic activation of distinct PKC isoenzyme(s). 相似文献
957.
958.
The mechanism(s) of adverse reactions to sulfites remains unclear. To determine whether mast cell degranulation is involved in sulfite sensitivity, we performed single-blind, placebo-controlled oral aqueous challenges with potassium metabisulfite in 13 patients with histories suggestive of sulfite sensitivity. Ten patients were also skin tested with potassium metabisulfite at 10 mg/mL and all had negative reactions. Serum samples were obtained from all the patients before the challenge and for 180 minutes after the challenge. The samples were tested for the presence of neutrophil chemotactic factor of anaphylaxis, using both a 51chromium microchamber chemotaxis assay and a leukocyte polarization technique. Six of 13 patients had positive challenges as defined by a fall equal to or greater than 20% in their forced expiratory volume in one second. No significant increase in neutrophil chemotactic factor activity was detected in the postchallenge serum samples from patients who experienced positive or negative challenges. We conclude that sensitivity to aqueous metabisulfite is not associated with mast cell degranulation in metabisulfite skin test-negative patients. 相似文献
959.
Marion S. Gaide Cynthia B. Altman John S. Cameron Charles J. Kaiser Robert J. Myerburg Arthur L. Bassett 《Inflammation research》1984,15(5-6):488-493
- Histamine (10?3 M) increased the spontaneous rate similarly in isolated preparations of normal left ventricular tissue from control, i.e. normal and sham-operated, dogs (control preparations) and in preparations consisting of normaland contiguous infarcted left ventricular tissue from dogs with subacute, i.e. 24 hours after left coronary artery ligation, myocardial infarction (infarcted preparations).
- Histamine (10?3 M) markedly enhanced the irregular rhythm of infarcted preparations.
- The H1-receptor antagonist, chlorpheniramine (10?4 M), and the H2-receptor antagonist, cimetidine (10?3 M), antagonized the effects of histamine (10?3 M) on the spontaneous rate of both control and infarcted preparations.
- The H1-receptor agonist, 2-pyridyl ethylamine (PEA, 10?4 M), increased the spontaneous rate of control and infarcted preparations; these effects were antagonized by chlorpheniramine (10?4 M). The H2-receptor agonist, dimaprit, had no effect.
- Similar to histamine (10?3 M), PEA (10?4 M) enhanced the irregular rhythm of infarcted preparations; dimaprit had no effect.
- High local concentrations of histamine may occur in poorly perfused ischemic tissue. The enhancement of irregular rhythm produced by histamine, and the specific H1-receptor agonist, PEA, leads us to suggest its involvement in arrhythmias associated with subacute myocardial infarction.
960.
0 引言 肝炎后高胆红素血症 ,极易与肝炎伴发高胆红素血症相混淆 .该病是肝炎后遗症之一 ,临床上并不少见 .患者常以间歇性黄疸或隐性黄疸前来就诊 ,但并无先天性黄疸、肝炎、肝硬化及肝内外胆管结石的临床证据 ,多数既往有肝炎病史 ,肝炎已达治愈标准 ,虽增加活动量亦无复发 ,临床预后良好 .现将我院 1995 - 10 / 1999- 0 9肝炎后高胆红素血症 18例作一小结 .1 临床资料 男 12例 ,女 6例 ,年龄 2 2~ 5 8(平均 40岁 ) .门诊 11例 ,住院 7例 .其中 11例曾患急性病毒性乙型肝炎 ,1例曾患中毒性肝炎 ,1例曾患药物性肝炎 ,5例无明确肝炎病… 相似文献