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111.
First generation Leishmania vaccines consisting of whole killed parasites with or without adjuvants have reached phase 3 trial and failed to show enough efficacy mainly due to the lack of an appropriate adjuvant. In this study, the nuclease-resistant phosphorothioate CpG oligodeoxynucleotides (PS CpG) or nuclease-sensitive phosphodiester CpG ODNs (PO CpG) were used as adjuvants to enhance immunogenicity and rate of protection against leishmaniasis. Due to the susceptibility of PO CpG to nuclease degradation, an efficient liposomal delivery system was developed to protect them from degradation. 1, 2-dioleoyl-3-trimethylammonium-propane (DOTAP) as a cationic lipid was used because of its unique adjuvanticity and electrostatic interaction with negatively charged CpG ODNs. To evaluate the role of liposomal formulation in protection rate and enhanced immune response, BALB/c mice were immunized subcutaneously with liposomal soluble Leishmania antigens (SLA) co-incorporated with PO CpG (Lip-SLA-PO CpG), Lip-SLA-PS CpG, SLA+PO CpG, SLA+PS CpG, SLA or buffer. As criteria for protection, footpad swelling at the site of challenge, parasite loads, the levels of IFN-γ and IL-4, and the IgG subtypes were evaluated. The groups of mice receiving Lip-SLA-PO CpG or Lip-SLA-PS CpG showed a high protection rate compared with the control groups. In addition, there was no significant difference in immune response generation between mice immunized with PS CpG and the group receiving PO CpG when incorporated into the liposomes. The results suggested that liposomal form of PO CpG might be used instead of PS CpG in future vaccine formulations as an efficient adjuvant.  相似文献   
112.

Background

The study was aimed to show the effect of molecular mechanism of Aqueous Garlic Extract (AGE) on expression of IFNγ and iNOS genes in Leishmania major.

Methods

Leishmania major promastigotes (MRHO/IR/75/ER) were added to the in-vitro cultured J774 cell line, the cells were incubated for 72 hours. Various concentrations of garlic extract (9.25, 18.5, 37, 74, 148 mg/ml) were added to the infected cells. MTT assay was applied for cellular proliferation. After 72 hours of incubation, supernatants were collected and total RNA was extracted from the infected cells. The express of IFNγ and iNOS genes were studied by RT-PCR method.

Results

The colorimetric MTT assay after 3 days of incubation showed cytotoxic effect of garlic extract with an IC50 of 37 mg/ml. In addition, IFNγ and iNOS genes expression by RT-PCR indicated that garlic extract lead to over expression of these genes in J774 cell line infected with L. major.

Conclusion

Garlic extract exerts cytotoxic effect on infected J774 cell line. In addition, the hypothesis that garlic can improve cellular immunity with raising the expression of IFNγ and of iNOS genes confirmed.  相似文献   
113.

Background

Osteoporosis is the most common metabolic bone disease in the world and it is rapidly increasing in Iran. In this study the relationship between educational levels and osteoporosis was investigated among Iranian postmenopausal women.

Method and subjects

Seven hundred and six women aged 50-75 years old were randomly recruited from urban (n = 440) and rural (n = 266) areas in Guilan. Osteoporosis was diagnosed by quantitative ultrasound technique and dual X-ray absorptiometry. Serum 25(OH) D3, body weight and height were measured in all subjects. Other data including age, educational level, menopause age, medications and history of illness were also collected.

Results

We found that the prevalence of osteoporosis was significantly greater among women with low educational level than women with high educational status (18.0% vs 3.8% P < 0.0001). However, women with low educational level had higher mean serum level of vitamin D than women with high educational level. Osteoporosis was significantly more prevalent among women living in rural areas than women living in urban areas (19.1% v.s 13.3%, P < 0.0001).

Conclusion

This study showed that educational level is associated with bone health in this population of postmenopausal women with significantly higher osteoporosis found in lower social groups. Therefore, we suggest that women with low social level should be carefully evaluated for signs of osteoporosis during routine physical examinations.  相似文献   
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报道了用GC/MS方法及衍生化技术研究6甲氧基正丁苯酞(MBP)在大鼠肝微粒体中的代谢转化结果。6甲氧基正丁苯酞在苯巴比妥(PB)诱导的大鼠肝微粒体中主要转化为3羟基、γ羟基取代物,6羟基正丁苯酞与一个环氧化代谢产物  相似文献   
117.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg ̄(-1)·min ̄(-1)静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10,T1/2,Vd,Cl分别为0.0087min ̄(-1),78.03min,40.55ml·kg ̄(-1)和0.421ml·kg ̄(-1)·min ̄(-1);Ke0和Ce(50)分别为0.0048min ̄(-1)和2.01μg·ml ̄(-1).  相似文献   
118.
大鼠用6-甲氧基正丁苯酞(MBP)灌胃,收集0~24h尿液,经酶水解、提取浓缩、衍生化处理后用GC/MS分析。在大鼠0~24h尿液中,6-甲氧基正丁苯酞原药含量很低,主要以代谢物形式存在,依次为C-6脱甲基产物、C3-Cα环氧化物、γ-羟化物、β-羟化物以及两个次级代谢产物。6-甲氧基正丁苯酞体内代谢结果与其在肝微粒体中代谢结果基本一致。  相似文献   
119.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg-1·min-1静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10, T1/2,Vd,Cl分别为0.0087min-1,78.03min,40.55ml·kg-1和0.421ml·kg-1·min-1;KeOCe(50)分别为0.0048min-1和2.01μg·ml-1.  相似文献   
120.
干燥综合征神经系统病变的临床及病理分析   总被引:1,自引:0,他引:1  
目的探讨原发性干燥综合征(Sjogren综合征;pSS)神经系统病变的临床及组织病理特征。方法对18例并发神经系统损伤的pSS患者的临床及病理资料进行回顾性分析。结果周围神经系统病变pSS(PNS-pSS)表现为对称性感觉运动性周围神经病、多发性单神经病、感觉性周围神经病、颅神经损伤。中枢神经系统病变pSS(CNS-pSS)表现为多发性硬化、缓慢进展的认知障碍和共济障碍、脑炎。头颅MRI显示脑白质多发异常信号、脑白质、脑干及小脑多发异常信号、脑脓肿。唇黏膜活检示部分腺体萎缩,腺泡及间质内可见淋巴、单核吞噬细胞浸润。腓肠神经活检既有典型血管炎改变也有非血管炎性改变。脑活检可见白质脱髓鞘及小静脉周围炎性细胞浸润以及典型血管炎改变。结论Sjogren综合征导致的神经系统损伤呈多样性,且常先于Sjogren综合征的诊断之前出现。了解其神经系统损伤的临床表现、影像学特点及组织病理改变对认识本病具有重要的临床意义。  相似文献   
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