Double-blind, placebo-controlled food challenge (DBPCFC) as an office procedure: a manual

There is now enough experience with the use of double-blind, placebo-controlled, food challenge (DBPCFC) to recommend its use as an office procedure for most patients complaining of adverse reactions to foods. This manual discusses the practical methods required for the allergist to undertake DBPCFC in the office. Thorough histories supplemented by food allergen skin testing are used to design a DBPCFC that carefully attempts to reproduce the history of food-induced symptoms described by the patient. Precautions that must be taken are delineated before challenge, as is treatment that may be required if a reaction occurs. For those foods to which challenges are positive, longitudinal evaluation with repeated challenge at appropriate intervals help to determine whether or not the problem will resolve over a period of time.     

Effects of theophylline,terbutaline, and prednisone on antigen-induced bronchospasm and mediator release

Eleven subjects demonstrating clinical, skin, and inhalation sensitivity to grass or ragweed pollen underwent serial inhalation challenges, with and without orally administered theophylline, terbutaline, and prednisone. Comparisons of antigen sensitivity and mediator release were made during these challenges. All three drugs significantly reduced antigen sensitivity (PD₂₀ inhalation units increasing from 670 to ≧ 3,280). Peak plasma histamine levels after antigen challenge decreased from 11.4 ng/ml to ≦ 3.4 ng/ml during all drug administrations. Similarly, the percent increase in serum neutrophil chemotactic activity (NCA) also decreased, from 96% to ≦ 36% during drug administrations. However, even at antigen doses resulting in bronchospasm during drug administration the systemic appearance of NCA and histamine were reduced. We conclude that prednisone, theophylline, and terbutaline significantly reduce antigen-induced bronchospasm and mediator release. The occurrence of bronchospasm despite the inhibition of histamine and NCA suggests either that the local concentration of these mediators are critical or that other mediators produce the bronchospasm observed.     

IN VIVO DETOXIFICATION OF ENDOTOXIN BY THE RETICULOENDOTHELIAL SYSTEM

Evidence is presented that The normal RES extracts endotoxin from the circulation and inactivates it very rapidly. When the RES has been damaged, whether by a blockading agent, such as thorotrast, or by a reversible degree of hemorrhagic shock, it cannot extract more than a small per cent of the amount of the endotoxin the normal system can extract. Of that fraction of endotoxin which is extracted, very little is detoxified. An organ like the kidney, which does not contain a significant amount of RE tissue, does not extract more than an insignificant percentage of the injected amount, and therefore does not detoxify endotoxin. Since dephosphorylation is a process concurrent with detoxification, and does not occur in an organ which does not extract or inactivate a significant amount of injected endotoxin, it is probable that this process is an indirect index of detoxification. Within the time limits of these experiments, plasma alone does not inactivate endotoxin.     

AMP-18,一种新发现的胃黏膜保护因子

AMP-18是一种新发现的由胃腺体上皮细胞合成的小分子蛋白质,独特表达于胃黏膜,机体其他部位少见,胃癌组织中表达缺失．AMP-18 由185个氨基酸组成,除去N端信号肽(20个氨基酸)后大小约18 ku,第54-150个氨基酸组成高度保守的结构域(BRICHOS区域)承担主要的生理功能．AMP-18由胃腺体上皮细胞以胞吐的方式分泌到胃黏液中,他的合成和分泌与个体生长发育有关,并受福斯高林、吲哚美辛、地塞米松等药物的影响．目前发现 AMP-18的生理功能主要有促进胃黏膜上皮细胞的有丝分裂,促进细胞的迁徙,促胃肠黏膜损伤的修复,保持胃肠黏膜的完整等．     

Recent advances in the treatment of eosinophilic esophagitis

First described nearly 20 years ago, eosinophilic esophagitis (EoE) is an inflammatory disease of the esophagus characterized by eosinophilic infiltration of the esophageal epithelium. Over 50% of the current literature on EoE has been published in the last 3 years, signaling both a rising incidence and increased recognition of this disorder. Treatment options available for patients with EoE include dietary management and/or pharmacologic therapy. An individualized approach to treatment is preferred, with an emphasis on patient-parental preference. The objective of this article is to discuss the current and future treatment options for EoE.     

Fine needle aspiration cytology of clear cell "sugar" tumor (PEComa) of the lung: report of a case

PEComa (clear cell "sugar" tumor) of the lung is a rare benign tumor of the lung probably arising from the perivascular epithelioid cells (PECs). We report a case of pulmonary PEComa arising from the periphery of the right lobe of a 64-year-old male. To our knowledge, this is the second case in the English literature diagnosed by fine needle aspiration biopsy. In this case report, the clinical, cytologic and immunohistochemical features clear cell "sugar" tumor of the lung are discussed and compared with the previously published literature. The differential diagnosis and methods for distinguishing the various clear cells lesions in the lung are discussed.