20（S）-原人参二醇对人胚肾293细胞生长的抑制作用

目的：研究20（S）-原人参二醇（PPD）对人胚肾293细胞（HEK-293细胞）生长抑制作用。方法：采用台盼蓝染色和噻唑蓝（MTT）法观察PPD对HEK-293细胞增殖的抑制作用,同时通过Hoechst33258染色和DNA Ladder方法测定PPD对HEK-293细胞凋亡影响。结果：PPD可明显降低HEK-293细胞存活率和细胞活性,半数抑制浓度（IC50）为21.8μmol/L。PPD处理后HEK-293细胞核出现典型的凋亡形态学的改变,琼脂糖电泳呈现明显的DNALadder条带。结论：PPD对HEK-293细胞生长有明显的抑制作用并有剂量依赖关系。     

石嘴山市辖区中小学PPD试验结果状况调查

目的了解我市城市区中小学1~9年级人群的结核菌素(PPD)试验反应情况。方法选取我市辖区小学和初中的学生为检查对象,采用成都生物制品研究所生产的卡介菌纯蛋白衍生物(BCG-PPD),用1m l注射器吸取本品0.1m l(5 IU)于前臂掌侧中外1/3处皮内注射。结果不同年级组阳性率差别有统计学意义,阳性率随年龄增大而降低;性别间阳性率无显著差别;不同年级之间强阳性差异有统计学意义,强阳性率随年龄增长而上升。结论我市辖区中小学生结核菌感染率处于相对较低水平,强阳性率随年龄增大而上升,阳性率男女之间无明显差别。     

结核分枝杆菌潜伏感染早期两种检测方法的比较分析

目的比较结核分枝杆菌（Mycobacterium tuberculosis,MTB）特异性IFN-γ酶联免疫斑点法（Elispot）和结核菌素皮试（TB—PPD皮试）在MTB潜伏感染早期诊断的优异。方法采用自主研制的Elispot试剂盒（简称Elispot）对100例健康志愿者进行检测,并和TB—PPD皮试进行平行比较。结果100例健康志愿者中有50例TB—PPD皮试阳性（占50％）,Elispot检测阳性20例（占20％）。两种方法检测结果差异有统计学意义（x^2=20．45,P〈0．005）。结论MTB特异性IFN-γ Elispot试剂盒在健康人群中检测阳性率比传统的TB-PPD皮试要低,Elispot检测体外IFN-γ 应答反应在诊断MTB潜伏感染的价值优于TB—PPD皮试,在MTB潜伏感染早期诊断有较好的发展前景。     

Immunological and cytotoxicological characterization of tuberculin purified protein derivative (PPD) conjugated to single-walled carbon nanotubes

Tuberculosis (TB) represents one of the leading killers among all infectious disease. Protection against TB depends on the activation of T-helper type I (Th1) immune response. Carbon nanotubes (CNTs) have attracted considerable attention because of their potential applications as new nanovehicle. In the current study, tuberculin purified protein derivative (PPD) was conjugated to carboxylated single-walled carbon nanotubes (SWCNTs). Cytotoxicity of the carboxylated SWCNT and SWCNT-PPD conjugate was analyzed with MTT assay and by reactive oxygen species (ROS) and nitric oxide (NO) generation. Male BALB/c mice were immunized with BCG, PPD, SWCNT-PPD conjugate and PPD in complete Freund's adjuvant (CFA). Induction of cellular immune response was analyzed by measuring the levels of Th1 cytokines (IFN-γ and IL-12) and Th2 cytokines (IL-10 and IL-5). Immunization with non-conjugated PPD or PPD in Freund's adjuvant induced a Th2 cytokine response while immunization with BCG resulted to a mixed Th1/Th2 cytokine response. In contrast, PPD in conjugation with SWCNT generated preferentially a Th1-type cytokine response in the absence of potential cytotoxic effects.     

Investigation of the immunogenicity of p-phenylenediamine and Bandrowski's base in the mouse

p-Phenylenediamine (PPD) exposure is associated with T-cell mediated contact dermatitis. T-cells from allergic patients proliferate following exposure to PPD and the oxido-conjugation product Bandrowski's base (BB). Both compounds are classified as sensitizers in the local lymph node assay; however, because of their instability the nature of the antigenic determinant remains ill-defined. The aim of this study was to explore the immunogenic potential of PPD and BB in mice. Spleen cell proliferation and cytokine secretion was measured ex vivo following antigen recall with soluble PPD or BB and either irradiated or glutaraldehyde fixed, antigen pulsed dendritic cells from syngeneic mice. Glutathione was added to certain incubations. LC–MS analysis and solvent extraction were used to monitor the fate of [¹⁴C]BB in culture and the extent of BB binding, respectively. Spleen cells from BB exposed, but not PPD- or vehicle-exposed, mice proliferated when stimulated with BB. Proliferating cells secreted high levels of IFN-γ, GM-CSF and IL-2. Stimulation with PPD instigated low levels of proliferation. Irradiated, but not fixed, dendritic cells pulsed with BB stimulated proliferation signifying a classical hapten mechanism involving irreversible BB binding to protein and processing. BB bound preferentially to serum protein when incubated together with cells and serum. Degradation of BB in the presence of glutathione was associated with a stronger stimulation of specific T-cells at higher BB concentrations. These data demonstrate that BB is a potent immunogen in the mouse.     

酶联免疫斑点法检测结核性胸水T淋巴细胞分泌IFN-γ的免疫功能

目的:研究结核性胸膜炎患者胸水T淋巴细胞(TLC)特异性分泌γ-干扰素(IFN-γ)的免疫反应,为结核性胸水的诊断提供依据。方法:应用淋巴细胞分离技术分离13例结核性胸水和11例恶性胸水TLC,体外利用PPD抗原刺激,用酶联免疫斑点法(ELISPOT)检测两组胸水TLC分泌IFN-γ的免疫反应。每例患者院内常规做PPD试验。结果:结核性胸水TLC分泌IFN-γ的免疫反应阳性率为84.62%(11/13例),明显高于恶性胸水组18.18%(2/11例),两者之间差异有显著性(P<0.01)。ELISPOT和PPD试验的敏感性分别为84.62%,46.15%,两者之间有明显差异性(P<0.01)。而ELISPOT和PPD试验的特异性分别为81.82%,90.91%,两者之间差异不明显。结论:ELISPOT检测结核性胸膜炎的敏感性和特异性均较高,有助于临床上对结核性胸水的鉴别诊断。     

Allergic contact dermatitis from hair dye and development of lichen simplex chronicus

Those who dye their hair frequently manifest allergic contact dermatitis (ACD) from p-phenylenediamine (PPD)-containing hair dye. PPD is known to be the most frequent sensitizer in hair dye, but there has been no documentation of this sensitizer having a role in chronic dermatologic conditions. Our department experienced a case of a 62-year-old woman with lichen simplex chronicus (LSC), who complained of aggravation after hair dyeing and made such an association. We conducted a prospective and retrospective study to further evaluate the clinical associations between the two. In our prospective study, patch testing was performed in selected patients who regularly carried out hair dyeing and also had clinical manifestations of LSC. Also a retrospective examination was conducted in cases where patch testing had been performed with PPD in the past for suspected ACD and further selected cases with concurrent LSC and/or other neurodermatitis. 11 and 14 patients in our prospective and retrospective study, respectively, presented with both LSC and positive findings to PPD. 5 (45.5%) and 4 (28.6%) patients in our prospective and retrospective study showed clinical relevance from clinical improvement after stopping use and rechallenge. We report several cases of patients diagnosed as having LSC and/or prurigo nodularis who showed clinical improvement after discontinuing the use of hair dye. The suggestion can therefore be made that hair dye could be a possible aetiologic agent causing LSC in those using hair dyes.     

Epidemiological data on consumer allergy to p‐phenylenediamine

Many women and men now dye their hair. p‐Phenylenediamine (PPD) is a frequent and important component of permanent hair dye products; exposure to it may cause allergic contact sensitization, acute dermatitis, and severe facial oedema. To increase our understanding of PPD allergy, we reviewed published literature containing PPD patch test data from dermatitis patients and individuals in the general population. This was performed to estimate the median prevalence and the weighted average of PPD sensitization and thereby assess the burden of PPD‐containing hair care products on health. Literature was examined using PubMed–MEDLINE, Biosis, and Science Citation Index. The median prevalence among dermatitis patients was 4.3% in Asia, 4% in Europe, and 6.2% in North America. A widespread increase in the prevalence of PPD sensitization was observed among Asian dermatitis patients. In Europe, a decrease in the 1970s was replaced by a plateau with steady, high prevalences ranging between 2% and 6%. The prevalence remained high in North America, although a decreasing tendency was observed. Contact allergy to PPD is an important health issue for both women and men. More stringent regulation and enforcement are required as public health measures to reduce the burden of disease that exposure to PPD has brought to populations.     

Knowledge and Awareness of Tuberculosis Among Pre-University Students in Trinidad

The purpose of the study was to determine the level of knowledge and attitudes among pre-university students in Trinidad and Tobago on the pre-disposing factors and prevention of tuberculosis and the management of persons with the disease. More than 90% (542 of 600) of participating students from nine secondary schools duly completed the self-administered questionnaires. Two-thirds of the students were girls (336) and the rest were boys (206). The ages of the participants ranged from 16–19 years and more than 82% of them belonged to the 17–18 year old age group. The least represented was the 19 year olds. The study showed that although 92.8% had heard of tuberculosis, overall knowledge about the disease was generally poor. The majority of students (77.5%) believed the disease could be prevented, but 10.3% knew of the BCG vaccine and only 11.1% knew about the Mantoux skin test. The study also demonstrated the need for renewed efforts in health education for the public, clarifying areas of misunderstandings about important and common diseases like tuberculosis, in developing countries.     

胸水抗 PPD-IgG 和 PCR 联合检测诊断结核性胸膜炎

目的　探讨结核性胸膜炎的检测方法 ,提高阳性检出率。方法　将已确诊的 82例结核性胸膜炎患者分别进行抗PPD IgG、PCR检测及两种方法联合检测。结果　两种方法单独应用检出率分别为 70 .5 %、5 9 .8% ;联合检测的检出率为 80 .5 %。结论　胸水抗PPD IgG和PCR联合检测能够提高对结核性胸膜炎的阳性检出率