Detection of radiolabelled bone marrow cells bearing surface ace immunoglobulins by combined autoradiography and immunoperoxidase

A method is described for the simultaneous detection of radiolabelled bone marrow cells bearing surface immunoglobulins by combined autoradiography and immunoperoxidase. Bone marrow cells from normal CBA mice prelabelled in vivo with ¹²⁵IUDR or exposed in vitro to [³H]thymidine were incubated with rabbit anti-mouse immunoglobulins under capping conditions, washed, cytocentrifuged and treated with methanol and hydrogen peroxide to destroy endogenous peroxidase. Cells were then covered with peroxidase-conjugated goat anti-rabbit immunoglobulins, washed, treated with diaminobenzidine a and hydrogen peroxide and finally covered with autoradiographic stripping film and exposed for different times. Peroxidase-positive cells were typically capped and those radiolabelled had autoradiographic silver grains overlying the nucleus.     

肺组织β-AR和GRK2与重症急性胰腺炎肺损伤的关系以及甲强龙的影响

目的：探讨重症急性胰腺炎（SAP）致急性肺损伤（ALI）大鼠肺组织β-AR和G蛋白偶联受体激酶2（GRK2）的变化规律以及甲强龙的影响。方法：SD大鼠36只，随机分为3组，每组12只。对照组，仅做十二指肠翻动；模型组，胰胆管逆行注射5%牛磺胆酸钠（1 mL/kg），建立SAP模型；干预组，建立SAP模型后1 h给予甲强龙（30 mg/kg）。于6 h和12 h分别处死大鼠6只取肺组织，放射配基结合实验测量肺组织β-AR最大结合容量B_max和平衡解离常数K_d，免疫荧光法检测肺组织GRK2表达。结果：模型组和干预组胰腺组织损伤评分显著高于对照组，模型制备成功；模型组和干预组肺组织损伤评分显著高于对照组，发生SAP肺损伤；模型组β-AR B_max显著低于对照组和干预组，K_d显著高于对照组和干预组；模型组GRK2的表达显著高于对照组和干预组。结论：SD大鼠肺组织有丰富的GRK2表达，SAP肺损伤大鼠肺组织GRK2表达显著增加，这可能是β-AR下调的重要机制。     

中国庚型肝炎病毒河南株非结构基因（NS）3区cDNA的克隆 …

目的 为了研究中国庚型肝炎病毒（ＨＧＶ）非结构（ＮＳ３）区基因结构特征。方法 利用逆转录－半巢式－聚合酶链反应从河南１份ＨＧＶ ＲＮＡ阳性血清获得覆盖ＨＢＶ ＮＳ３全长ｃＤＮＡ的４个片段，并克隆到ｐｃＤＮＡⅡ载体中，采用Ｓａｎｇｅｒ双脱氧末端终止法测定全部ｃＤＮＡ序列。结果 发现克隆到的包括ＨＢＶ ＮＳ３区在内的ｃＤＮＡ序列和度为２１３７个核苷酸，编码７１１个氨基酸。与国内外已测定的５株全序列的相     

Acquired α2 macroglobulin on the surface of human lymphoblastoid cells

The molecular nature of the membrane antigen that is acquired from FCS-containing media by human lymphoblastoid cells has been investigated. The presence of bovine α₂, macroglobulin on the surface of Namalva cells was demonstrated by radioimmunoassay using specific antisera. Alternatively, cell-bound bovine α₂,M could be detected by the more sensitive heterophile rosette assay described previously. Namalva cells grown in NHS-containing media acquired bovine α₂ M upon subsequent incubation with the purified protein in a dose- and time-dependent way. Acquisition of α₂ M was demonstrated using both viable and formaldehyde-fixed cells. Purified fetuin, which carries a heterophile epitope shared with bovine α₂ M as well as with other glycoproteins, failed to bind with the membrane of Namalva cells. The possible role of acquired α₂ macroglobulin on cells has been discussed.     

Association analysis of a polymorphism in the G‐protein stimulatory α subunit in patients with major depression*

Growing evidence suggests that G‐proteins may be involved in pathogenesis and treatment of affective disorders. Several studies have reported altered levels and/or activities of stimulatory G‐proteins in depression. The aim of this study was to investigate whether a polymorphism in the stimulatory α subunit of G‐proteins (T/C point mutation in exon 5; ATT → ATC at codon 131) is associated with major depression or response to antidepressant treatment. Therefore, we performed a case‐control association study with 212 depressive patients and 137 healthy, unrelated controls. There was no evidence for an association between the investigated polymorphism in the Gα_s gene and major depression, as well as to treatment response. The results of our study are in concordance with recently published findings which do not support the hypothesis that the gene for the stimulatory α subunit of G‐proteins is a major susceptibility factor in the pathophysiology of major depression. © 2002 Wiley‐Liss, Inc.     

Utility of the ratio of food-specific IgE/total IgE in predicting symptomatic food allergy in children

BACKGROUND: Double-blind, placebo-controlled food challenges are time-consuming, expensive and not without risk to patients. Therefore, an in vitro test that could accurately diagnose food allergy would be of great value. OBJECTIVE: To evaluate the utility of the ratio of specific immunoglobulin E (IgE)/total IgE compared with specific IgE (sIgE) alone in predicting symptomatic food allergy. METHODS: We retrospectively analysed 992 controlled oral food challenges performed in 501 children (median age 13 months). The ratio of sIgE/total IgE was calculated and tested for correlation with the outcome of food challenges. Receiver operator characteristics (ROC)-curves were performed; predicted probabilities and predictive decision points were calculated. RESULTS: A significant correlation was found between the ratio and the outcome of food challenges for cow's milk (CM), hen's egg (HE), and wheat, but not for soy. The ROC and predicted probability curves as well as sensitivity and specificity of the decision points of the ratio were similar to those of sIgE levels for CM, HE and wheat. CONCLUSION: In view of the greater effort needed to determine the ratio, without benefit compared with the sIgE alone, the calculation of the ratio of sIgE/total IgE for diagnosing symptomatic food allergy offers no advantage for CM, HE, wheat or soy. For the majority of cases controlled oral food challenges still remain the method of choice.     

A graded dose assessment of the efficacy of beclomethasone dipropionate aerosol for severe chronic asthma.

In a 26-wk double-blind controlled study of 34 patients whose asthma had been poorly controlled despite oral steroids, valuable clinical and pulmonary function improvement was derived by adding beclomethasone aerosol to the prednisone regimen. The amount of improvement correlated linearly with beclomethasone dosage over the range 200 to 1,600 microng/day. These patients required relatively high dosage. Success in achieving asymptomatic status was only 26% with the conventional 400 microng/day and 60% at 1,600 microng/day. Oropharyngeal candidiasis was also dose-related but did not prohibit the use of high-dosage beclomethasone. Respiratory infections, physical signs, blood glucose, and electrolytes were unaffected by the drug. A dose-related suppression of cortisol secretion was demonstrated, but about 1/4 of the group had normal plasma cortisol even at 1,600 microng/day plus the oral prednisone. An individualized risk-benefit assessment seems a better basis for choosing an optimal beclomethasone regimen for each patient than adherence to a conventionalized fixed dosage of 400 microng/day. This requires definition of: (1) a specific goal of treatment in the individual patient and the beclomethasone dosage required to achieve it; (2) the adrenocortical functional response of that particular patient to the desired dose of beclomethasone; and (3) the presence and degree of any dose-limiting constraints such as preexisting complications of steroid use.     

Improved method for the isolation of purified mouse peritoneal macrophages

Mouse peritoneal macrophages were cultured for 45 min in medium supplemented with fetal calf serum (FCS) in petri dishes coated overnight with heat-inactivated FCS. After removal of non-adherent cells by washing, adherent cells were detached by a brief incubation in the presence of sub-toxic levels of ethylenediamine tetraacetate (EDTA). Overall peritoneal macrophage recoveries of 90% can be routinely achieved with this method, and full cell viability is maintained.     

Summation of fibre potentials and the e.m.g.-force relationship during the voluntary movement of a forearm

A linear mathematical model of the electromyogram (e.m.g.) has been developed for the biceps muscle. The number of motor units (and therefore muscle fibres) contributing to the resultant e.m.g. at any stage of movement has been found from the force analysis of elbow flexion. The depths of various motor units and the phase difference between the recruitment of any two motor units have been formulated using a spiral spread of recruitment sequence. The attenuation of individual motor-unit action potentials due to varying depths has been taken into consideration, and due regard has been taken of the length-tension diagram of a muscle while performing the force analysis. Attention has been focused on the flexion of the elbow joint, in which a method of finding the individual contribution of the biceps and brachialis muscles has been developed and applied. The results predicted by the model have been verified by experiments. The model can also be extended to the e.m.g. of other fast skeletal muscles. The conditions and limitations for such generalisations have been stated and discussed.     

The effect of beta adrenergic blockade on bronchial sensitivity to acetyl-beta-methacholine in normal and allergic rhinitis subjects.

The effect of propranolol inhalation on sensitivity to methacholine inhalation was studied in normal and allergic rhinitis subjects to determine whether beta adrenergic blockade alters sensitivity to mediators in nonasthmatic atopic individuals. A partial beta adrenergic blockade is suggested as being instrumental in asthma. Hay fever patients studied showed similar effects and also developed asthma for the first time.