HB-Ⅰa冻干脂质体粒径及其分布的研究

研究了降温速率、保护剂种类与浓度、复溶溶液对HB-Ⅰa冻干脂质体粒径的影响.由逆相蒸发法制得的HB-Ⅰa脂质体大多为大单室和多室脂质体,粒径主要分布在1～10μm之间.约20K/min的降温速率对HB-Ⅰa脂质体冻干较为有利;蔗糖的保护效果较优,甘露醇次之,PVP和甘氨酸相对较差,蔗糖和甘氨酸组成的二元保护剂保护效果较蔗糖更好;缓冲溶液较纯水或蔗糖溶液的复溶效果好.     

Inflammation and arthritis: perspectives of the glycobiologist

This review focuses on the role of glycosylation during the development of joint inflammation and degeneration. Although glycoproteins and glycan-binding proteins have essential functions in bone and cartilage, and in the inflammatory process, their exact roles are still uncertain due to the vast complexity of carbohydrate structures. Glycosylated epitopes have been shown to play a role in the induction of arthritis in animal models. Currently available drugs are aimed at the protection of cartilage and bone structures but new developments in this area should take into account the tight and specific interactions between bone and cartilage. It is anticipated that new agents will help to remodel damaged joints, based on knowledge of cartilage and bone turnover and on the exact role of glycosylated molecules and cell surface receptor glycoproteins in these processes. Highly sensitive imaging techniques and well-characterized In vivo models will accelerate this development.     

Identification and localisation of glycosyl moieties of surface glycoproteins of teliospore wall of Karnal bunt (Tilletia indica) of wheat

This article aims to characterise and localise the glycosyl moieties of teliospore wall of Tilletia indica a quarantined fungal pathogens by biochemical and immunological approaches. Chemical enzyme modifier studies, followed by determination of structural configuration using phase contrast and SEM after periodate treatment, showed antigenic entities are glycoprotein in nature. Further characterisation using sodium dodecyl sulphate-polyacrylamide gel electrophroesis (SDS-PAGE) glycoprotein staining and western blotting using anti-teliospore antibodies showed two common proteins of molecular weight 28 and 40 kDa, which is also suggestive of glycoprotein nature of antigenic entities of teliospore wall. To study the binding patterns and localisation of glycosyl moieties on the teliospore walls, fluorescein isothiocyanate (FITC) labelled lectins [Wheat Germ Agglutinin (WGA) and Concanavilin A (Con A)] and anti-teliospore antibodies were used. The patterns of WGA and anti-teliospore antibodies binding with teliospore wall are almost similar and hence it is quite reasonable to suggest that immunodominant glycosyl entities of teliospore wall are acetylglucosamine in nature.     

Engineering of a recombinant trivalent single-chain variable fragment antibody directed against rabies virus glycoprotein G with improved neutralizing potency

Human and equine rabies immunoglobulins are currently available for passive immunization against rabies. However, these are hampered by the limited supply and some drawbacks. Advances in antibody engineering have led to overcome issues of clinical applications and to improve the protective efficacy. In the present study, we report the generation of a trivalent single-chain Fv (scFv50AD1-Fd), that recognizes the rabies virus glycoprotein, genetically fused to the trimerization domain of the bacteriophage T4 fibritin, termed ‘foldon’ (Fd). scFv50AD1-Fd was expressed as soluble recombinant protein in bacterial periplasmic space and purified through affinity chromatography. The molecular integrity and stability were analyzed by polyacrylamide gradient-gel electrophoresis, size-exclusion chromatography and incubation in human sera. The antigen-binding properties of the trimeric scFv were analyzed by direct and competitive-ELISA. Its apparent affinity constant was estimated at 1.4 ± 0.25 × 10⁹ M⁻¹ and was 75-fold higher than its monovalent scFv (1.9 ± 0.68 × 10⁷ M⁻¹). The scFv50AD1-Fd neutralized rabies virus in a standard in vitro and in vivo neutralization assay. We showed a high neutralization activity up to 75-fold compared with monovalent format and the WHO standard serum. The gain in avidity resulting from multivalency along with an improved biological activity makes the trivalent scFv50AD1-Fd construct an important reagent for rabies protection. The antibody engineering approach presented here may serve as a strategy for designing a new generation of anti-rabies for passive immunotherapy.     

Acute and subacute myelopathy

Myelopathy is a term referring to any pathologic process affecting the spinal cord, and encompasses a broad spectrum of etiologies. The first step is to categorize myelopathy, according to the time to reach maximum deficit. Myelopathies are commonly classified as acute, subacute or chronic, for which the etiologies are totally different. Myelopathy is considered acute when the symptoms progress to their nadir in maximum 21 days after onset. Due to heterogeneity in pathogenesis, and the overlap in the clinical and imaging presentation among etiologies, acute myelopathy is considered as a diagnostic dilemma. A simple and efficient algorithm for timely identification of the underlying cause is thus useful. In this review, we provide a simplified approach for the differential diagnosis among all causes of acute myelopathies, and describe the principal clinical and imaging features of the main etiologies in adults, including recently characterized antibody-mediated myelitis, and its mimics.     

通阳中药葱白提取物抑制低压低氧诱导促凝血反应的机制研究

目的研究通阳中药葱白提取物(AYMOE)对低压低氧诱导的血小板激活和促凝状态的影响。方法将42只成年雄性SD大鼠随机分为对照组(暴露于常压常氧环境)、低压低氧组(Hyp组,暴露于低压低氧环境)、Hyp+AYMOE-100组(暴露于低压低氧环境并口服AYMOE 100 mg/kg)、Hyp+AYMOE-200组(暴露于低压低氧环境并口服AYMOE 200 mg/kg)、Hyp+AYMOE-300组(暴露于低压低氧环境并口服AYMOE 300 mg/kg)、Hyp+anti-CD42c组(暴露于低压低氧环境并尾静脉注射antiCD42c 5 mg/kg)、Hyp+AYMOE-200+rh Lyn组[暴露于低压低氧环境并口服AYMOE 200 mg/kg联合尾静脉注射重组人酪氨酸蛋白激酶Lyn(rh Lyn) 4.8 mg/kg],每组6只。低压低氧暴露7 d后,ELISA检测各组大鼠血清血栓素A2(TXA2)以及血小板激活因子(PAF)含量,检测大鼠血小板的凝集率,HE染色观察大鼠肺组织病理变化,Western blot检测GPIb-Ⅸ-Ⅴ、Lyn、磷酸化的Lyn(p-Lyn)的表达。结果与对照组比较,暴露于低压低氧的各组大鼠血清TXA2、PAF水平及血小板凝集率升高,GPIb-Ⅸ-Ⅴ、Lyn、p-Lyn蛋白表达上调(P <0.05)。与Hyp组相比,Hyp+AYMOE-100组、Hyp+AYMOE-200组、Hyp+AYMOE-300组的血小板凝集率、血清TXA2、PAF的水平降低,差异均有统计学意义(P <0.05),其中以Hyp+AYMOE-200组抑制效果最明显(P <0.05)。与对照组比较,Hyp组大鼠因低氧而发生血管堵塞,肺静脉血管腔空间狭小;与Hyp组相比,Hyp+AYMOE-200组大鼠肺静脉血管栓塞明显缓解。与Hyp组相比,Hyp+anti-CD42c组和Hyp+AYMOE-200组GPIb-Ⅸ-Ⅴ、Lyn、p-Lyn蛋白表达下调,差异均有统计学意义(P <0.05)。与Hyp+AYMOE-200组比较,Hyp+AYMOE-200+rh Lyn组血小板凝集率、血清TXA2和PAF水平均较高,Lyn和p-Lyn蛋白表达均增加,差异均有统计学意义(P <0.05)。结论 AYMOE可通过抑制GPIb-Ⅸ-Ⅴ和Lyn减少低压低氧诱导的血小板激活并改善促凝状态。     

Oncolytic Virus Therapy with HSV-1 for Hematological Malignancies

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Herpesvirus entry mediator (HVEM) attenuates signals mediated by the lymphotoxin β receptor (LTβR) in human cells stimulated by the shared ligand LIGHT

Signals mediated by members of the tumor necrosis factor receptor superfamily modulate a network of diverse processes including initiation of inflammatory responses and altering cell fate between pathways favoring survival and death. Although such pathways have been well-described for the TNF-α receptor, less is known about signaling induced by the TNF superfamily member LIGHT and how it is differentially altered by expression of its two receptors LTβR and HVEM in the same cell. We used cell lines with different relative expression of HVEM and LTβR to show that LIGHT-induced signals mediated by these receptors were associated with altered TRAF2 stability and RelA nuclear translocation. Production of the inflammatory chemokine CXCL10 was primarily mediated by LTβR. Higher expression of HVEM was associated with cell survival, while unopposed LTβR signaling favored pathways leading to apoptosis. Importantly, restoring HVEM expression in cells with low endogenous expression recapitulated the phenotype of cells with higher endogenous expression. Together, our data provide evidence that relative expression of HVEM and LTβR modulates canonical NF-κB and pro-apoptotic signals stimulated by LIGHT.