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Using a solid-phase radioimmunoassay, serum IgE level was determined in 46 normal subjects, 53 patients with bronchial asthma, 44 patients with chronic bronchitis and / or emphysema, and 19 patients with restrictive lung disease. Sputum IgE was measured simultaneously in 51 of the subjects. The range of serum IgE concentration in the normal subjects was wide. It varied between 15 and 750 ng/ml with a mean of 135 ng. Asthmatic patients had significantly higher levels of serum IgE with a mean of 579 ng/ml, but only 30% fell outside the normal 95% confidence limits. Patients with chronic bronchitis, emphysema and restrictive lung diseases had normal IgE levels. There was a significant correlation between serum and sputum IgE levels. 相似文献
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The possibility that a growth-related proteinase may act by degrading a negative growth regulatory protein has been investigated. Proteinase inhibitors which inhibit the enzyme also enhance the accumulation of the growth regulator by human fibroblasts. The negative growth regulator shows a similar specificity of inhibition of cellular growth to inhibitors of the growth-related proteinase. 相似文献
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Robert J. Cook James Tse Walter N. Piper 《Archives of biochemistry and biophysics》1982,216(2):593-599
δ-Aminolevulinic acid synthetase (EC 2.3.1.37) has been detected in homogenates of rat ovaries. Optimal substrate and coenzyme concentrations, and parameters for assay of ovarian δ-aminolevulinic acid synthetase have been determined. Subcellular fractionation studies have shown that enzyme activity is predominantly localized in the mitochondrial fraction. Fasting, which is known to increase enzyme activity in the adrenal and to have no effect on activity in the testis, had no effect on enzyme activity in the ovary. Administration of the hepatic inducer allylisopropylacetamide or the hormone progesterone failed to alter activity of the ovarian enzyme. The activity of the enzyme was significantly increased during the diestrus-1 phase of the estrus cycle, during pregnancy, and by human chorionic gonadotropin at 24 and 48 h, suggesting that ovarian δ-aminolevulinic acid synthetase and the synthesis of heme may be under hormonal control. 相似文献
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Yiying Cai Hui Leck Tze Peng Lim Jocelyn Teo Winnie Lee Li Yang Hsu Tse Hsien Koh Thuan Tong Tan Thean-Yen Tan Andrea Lay-Hoon Kwa 《PloS one》2015,10(10)
Background
Current in vitro combination testing methods involve enumeration by bacterial plating, which is labor-intensive and time-consuming. Measurement of bioluminescence, released when bacterial adenosine triphosphate binds to firefly luciferin-luciferase, has been proposed as a surrogate for bacterial counts. We developed an ATP bioluminescent combination testing assay with a rapid turnaround time of 24h to determine effective antibiotic combinations.Methods
100 strains of carbapenem-resistant (CR) GNB [30 Acinetobacter baumannii (AB), 30 Pseudomonas aeruginosa (PA) and 40 Klebsiella pneumoniae (KP)] were used. Bacterial suspensions (105 CFU/ml) were added to 96-well plates containing clinically achievable concentrations of multiple single and two-antibiotic combinations. At 24h, the luminescence intensity of each well was measured. Receiver operator characteristic curves were plotted to determine optimal luminescence threshold (TRLU) to discriminate between inhibitory/non-inhibitory combinations when compared to viable plating. The unweighted accuracy (UA) [(sensitivity + specificity)/2] of TRLU values was determined. External validation was further done using 50 additional CR-GNB.Results
Predictive accuracies of TRLU were high for when all antibiotic combinations and species were collectively analyzed (TRLU = 0.81, UA = 89%). When individual thresholds for each species were determined, UA remained high. Predictive accuracy was highest for KP (TRLU = 0.81, UA = 91%), and lowest for AB (TRLU = 0.83, UA = 87%). Upon external validation, high overall accuracy (91%) was observed. The assay distinguished inhibitory/non-inhibitory combinations with UA of 80%, 94% and 93% for AB, PA and KP respectively.Conclusion
We developed an assay that is robust at identifying useful combinations with a rapid turn-around time of 24h, and may be employed to guide the timely selection of effective antibiotic combinations. 相似文献10.