胶体金标法快速检测鼠疫F1抗体的现场应用

目的了解胶体金标快速检测试剂盒检测鼠疫FI抗体的现场应用。方法按鼠疫快速诊断盒(胶体金标法)的使用说明进行,并与间接血凝微量法(IHA)进行比较。结果检测了来自云南家鼠鼠疫流行区和非流行区血清共335份,检出腺鼠疫病人血清阳性32份,与IHA法结果一致。结论胶体金标鼠疫FI抗体快诊盒诊断鼠疫简便、快速、特异、敏感,便于现场鼠疫监测应用。     

Epicutaneous antigen exposure primes for experimental eosinophilic esophagitis in mice

BACKGROUND & AIMS: Eosinophilic esophagitis (EE) is frequently associated with atopic disease, including dermatitis and asthma. Data are emerging that atopic skin may provide an early entry point for antigen sensitization. We aimed to test the hypothesis that epicutaneous exposure to antigen primes for subsequent respiratory antigen-induced EE. METHODS: Wild-type and genetically engineered mice were subjected to epicutaneous antigen sensitization and the development of experimental EE, and immune responses were examined. RESULTS: We show that exposure to antigen via the epicutaneous route primes for marked eosinophilic inflammation in the esophagus triggered by a single airway antigen challenge. The development of experimental EE is associated with significant skin eosinophilia, accelerated bone marrow eosinophilopoiesis, blood eosinophilia, and large increases in serum antigen-specific immunoglobulin G1/immunoglobulin E using ovalbumin or Aspergillus fumigatus as the epicutaneous antigen. Mechanistic analysis with gene-targeted mice showed that interleukin-5 was required for esophageal eosinophilia and that interleukin-4, interleukin-13, and STAT6 contributed to a lesser extent. CONCLUSIONS: These findings provide the first evidence that epicutaneous exposure to allergens potently primes for EE via a Th2-dependent mechanism.     

Patterns of immunoglobulin G responses to egg and peanut allergens are distinct: ovalbumin-specific immunoglobulin responses are ubiquitous, but peanut-specific immunoglobulin responses are up-regulated in peanut allergy

BACKGROUND: The clinical significance of food-specific IgG subclasses in food allergy and tolerance remains unclear. Specific IgG titres are often reported in non-standardized units, which do not allow comparisons between studies or allergens. OBJECTIVE: To quantify, in absolute units, ovalbumin (OVA)- and peanut-specific IgG levels in children with peanut or egg allergy (active or resolved) and in non-allergic controls. Methods Children aged 1-15 years were recruited. Peanut allergy was diagnosed by convincing history and a 95% predictive level of specific IgE; egg allergy or resolution was confirmed by oral challenge. Serum IgG, IgG1 and IgG4 levels (microg/mL) to OVA and peanut extract were quantified by ELISA. RESULTS: OVA- and peanut-specific IgG was detected in all subjects. In non-allergic controls (n=18), OVA-specific IgG levels were significantly higher than peanut-specific IgG (median microg/mL IgG=15.9 vs. 2.2, IgG1=1.3 vs. 0.6, IgG4=7.9 vs. 0.7; P<0.01). There were no differences in OVA-specific IgG, IgG1 and IgG4 between egg-allergic (n=40), egg-resolved (n=22) and control (n=18) subjects. In contrast, peanut-specific IgG (median microg/mL IgG=17.0, IgG1=3.3, IgG4=5.2) were significantly higher in peanut-allergic subjects (n=59) compared with controls and with non-peanut-sensitized but egg-allergic subjects (n=26). Overall, the range of IgG4 was greater than IgG1, and IgG4 was the dominant subclass in >60% of all subjects. CONCLUSION: OVA-specific IgG levels of egg-allergic, egg-resolved or control groups are not distinguishable. Higher peanut-specific IgG levels are associated with clinical allergy, but the range of IgG titres of the allergic and control groups overlapped. Hence, OVA and peanut-specific IgG measurements do not appear to be of diagnostic value. Strong IgG responses to OVA may be a normal physiological response to a protein frequently ingested from infancy, whereas up-regulated IgG responses in peanut allergy may be indicative of a dysregulated immune response to peanut allergens.     

Solid phase preparations of 99mTc labeled radiopharmaceuticals

For the preparation of most ^99mTc radiopharmaceuticals, SnCl₂ has remained the agent of choice for reduction of Tc⁷⁺ to lower valency states, which facilitates its chelation by compounds of diagnostic importance. We have developed a simple technique in which SnCl₂ lyophilized in a glass vial, either alone or on a solid matrix of polymeric microspheres (beads), was used. Tin‐113 (t_1/2 – 115 d) was used as a tracer, which facilitated quantitative assessment of loss or release of tin in the reaction mixtures. The feasibility and efficacy of this technique were examined for preparations of four ^99mTc‐ labeled peptides, in which SnCl₂ was used as a reducing agent for radiolabeling, a procedure well established in our laboratory. Labeling efficiencies for all four peptides using SnCl₂ on solid phase was greater than 95%, as compared to less than 90% (P=0.05) for SnCl₂ lyophilized without the solid matrix. Colloid formation was less than 3% in either case. The stability of SnCl₂ was greater than six months for solid matrix, and less for that without the microspheres. The ¹¹³Sn measured as a daughter product ^113mIn indicated that release of SnCl₂ from microspheres in reaction mixture was 85±3%, as compared to 80±5% lyophilized alone. The recovery of ^99mTc in solution from microspheres was 95–100%. The large size of the microspheres used (649 μm) eliminated the risk of drawing them through a needle in a syringe used for injection of a preparation. Copyright © 2002 John Wiley & Sons, Ltd.     

T cell proliferation and cytokine responses to ovalbumin and ovomucoid detected in children with and without egg allergy

BACKGROUND: The specific T cell responses in egg allergy and resolution have not been fully elucidated. OBJECTIVE: To characterize egg allergen-specific T cells of children with active and resolved egg allergy, in comparison with non-allergic controls. METHOD: We studied children with active (n=35) or resolved (n=20) egg allergy determined by oral challenge, and non-allergic controls (n=15). Peripheral blood mononuclear cells were labelled with carboxyfluorescein succinimidyl ester (CFSE) and stimulated with ovalbumin (OVA), ovomucoid (OM) or tetanus toxoid. Flow cytometry was used to detect divided CD3+ CFSE(lo) cells that expressed intra-cytoplasmic IL-4 or IFN-gamma. The cell division index (CDI) was calculated as a measure of allergen-specific proliferation. Peanut-specific T cells of a subgroup of children who also had peanut allergy were also studied. RESULTS: OVA-specific T cells were found in subjects with active (87%) or resolved (75%) egg allergy and in controls (67%), with a trend towards increased T cell proliferation in allergy. OM-induced weaker T cell responses than OVA, stimulating fewer responders (46% allergic, 50% resolved, 60% controls) and 10-fold less proliferation [CDI(OVA) 2.0 (median), 25.6 (maximum) vs. CDI(OM) 0.2 (median), 15.1 (maximum); P<0.01]. Both egg allergens induced significant IL-4+ (median 10%, range 1.4-58%) and IFN-gamma+ (median 28%, range 4.5-63%) cells in responders, including non-allergics. There were no significant differences in IFN-gamma+ or IL-4+ cells or in IFN-gamma/IL-4 ratios between groups. Peanut-specific T cell proliferation was significantly higher in peanut allergy [CDI(CPE) 16.5 (median), 24.8 (maximum)] compared with controls [CDI(CPE) 2.1 (median), 16.1 (maximum)] but cytokine profiles were not different. Tetanus-specific T cells were seen in 90% of the subjects, with no significant inter-group differences in responses. CONCLUSION: Egg allergen-specific T cells are readily detected in all groups and not restricted to egg allergy. In contrast, peanut-specific proliferation was significantly higher in peanut allergy. This suggests that T cell responses in peanut and egg allergy may differ. We did not find T helper type 2-deviated cytokine responses in egg or peanut allergy.     

尿脱氧吡啶用于绝经前子宫切除妇女骨代谢变化检测的研究

目的探讨绝经前子宫切除妇女术后骨代谢改变的最早时期。方法采用酶联免疫吸附法(ELISA法)检测60例绝经前行子宫切除妇女术后不同时期的尿脱氧吡啶(DPD)和血清骨钙素(BGP)水平,同时用全自动生化分析仪检测血清碱性磷酸酶(ALP)水平。采用单因素方差分析进行统计学处理。结果与对照组的比较,手术后2年组,≥3年组ALP,BGP水平升高(分别为P<0.05;P<0.01);DPD显著升高(均P<0.01);与手术后1年组比较,手术后2年组BGP、DPD升高,差异有统计学意义(分别为P<0.05,P<0.01),ALP变化无统计学意义(P>0.05)。手术后≥3年组ALP、BGP、DPD升高,差异有统计学意义(均为P<0.01)。结论术后2年是骨代谢改变的敏感期,应进行检测与预防,DPD是一个敏感的反映骨吸收的生化指标。     

Transverse relaxation of cells labeled with magnetic nanoparticles.

We describe the NMR relaxation properties of magnetically labeled cells. The cells are labeled with magnetic nanoparticles (SPIO, USPIO), which generate susceptibility contrast. The geometry of the labeled cells and the surrounding tissue is considered. We assume that the magnetic nanoparticles accumulate to form a magnetic core of radius RC inside the cell. The correlation time tau, which describes the motion of spins around this core, is analyzed. Using the strong collision approach, explicit expressions are derived for the transverse relaxation rate R2* for tissue containing labeled cells as a function of the core radius, the diffusion coefficient, and the concentration of the nanoparticles. The predictions of this model agree well with numerical simulations and experimental data.     

Immuno-suppressive lymphocyte factors—III. Complete purification and partial characterization of human inhibitor of DNA synthesis

Inhibitor of DNA synthesis (IDS) is an immunoregulatory T lymphocyte factor first characterized in the rat. It appears to cause the non-specific immune suppression seen in certain tolerant disease states.We have produced IDS from human peripheral blood lymphocytes, purified it to homogeneity and partiallycharacterized it. Human IDS has an isoelectric point of 3.40 and a molecular weight of 20,000. However, in the supernatants containing IDS activity, it usually exists in an aggregated tetrameric form which is also biologically active. IDS is not cytotoxic and is glycoprotein in nature. The activity depends on an intact carbohydrate moiety. Human IDS is identical to rat IDS except for a slightly higher isoelectric point. The biologic role is undetermined at present, but might be similar to that of rat IDS.     

豚鼠血液及肝、肺组织中钩端螺旋体数量变化与钩体病肺弥漫性出血的关系

作者采用同位素~(32)P标记钩端螺旋体放射性强度测定法和连续倍比稀释培养计数法,动态观察豚鼠血液、肝及肺组织中钩端螺旋体数量的变化,发现后腔静脉和肝中繁殖的钩端螺旋体数量的增加,与肺弥漫性出血的发生密切有关,并与出血的发展在时间和程度上均十分一致。表明在肝中新繁殖并经血液到肺的活钩端螺旋体本身与肺弥漫性出血有直接关系。     

Cyclic AMP and growth regulation in rat glioma cells in tissue culture

Peripheral neuropathy accompanied by decreased axonal conduction velocity is a common complication of diabetes. Skeletal muscle weakness and wasting also occur in the severe, uncontrolled form of the disease. For these reasons, it has been hypothesized that diabetes may cause denervation-like changes in skeletal muscle. In the present study, sarcolemmal membranes were characterized in control, early, and late stages of streptozotocin diabetes. After 3 weeks, axonal conduction velocities decreased 25% and muscle weight decreased 50% in diabetic rats. No significant changes were observed in Na⁺,K⁺ (Mg²⁺)-ATPase or adenylate cyclase activities during diabetes. The number of β-adrenergic receptor sites, however, increased from 0.39 pmol/mg in control sarcolemma to 0.46 and 0.58 pmol/mg after 6 and 18 days of diabetes, respectively, with no change in the affinity constant. Membrane phospholipid and polypeptide compositions were unaltered during diabetes, whereas the cholesterol content increased 23% in 18-day diabetic sarcolemma. There was also a 2.5-fold increase in glycosylation of a 72,000-molecular weight glycopeptide after 18 days of diabetes. Previous studies showed that denervation results in a decrease in sodium fluoride- and catecholamine-stimulated adenylate cyclase activities, an increase in Na⁺,K⁺ (Mg²⁺)-ATPase activity, no change in the number or affinity of β-adrenergic receptor sites, and no change in membrane glycosylation (1977. Exp. Neurol.56: 102–114). These findings demonstrate that diabetic and denervated skeletal muscle sarcolemma are distinctly different with respect to a number of their biochemical properties.