PGA指数和透明质酸在诊断慢性乙肝肝纤维化中的价值

目的：寻找一种简便实用的诊断慢性乙型肝炎纤维化的方法。方法：以78例经肝穿刺病理证实的慢性乙型肝炎为对象，测定并比较了由PT、GGT、ApoA1组成的PGA指数和HA、LN、PⅢP、C－IV与肝内纤维化程度(S)和炎症活动度（G）的关系。结果：（1）LN、PⅢP、C－IV在轻度慢性乙肝时无明显升高，在中度慢性乙肝时明显高于正常，但与轻度慢性乙肝无差异，而PGA指数和HA不仅在轻度慢性乙肝时显著升高，而且在轻中度间差异明显.因重度慢性乙肝和活动性肝硬化时，五项指标均显著增高。（2）在G2－4期，HA、LN、PⅢP、C－IV均明显高升，但在G1期，只有PGA指数高于正常，且各期间差异显著。（3）在S1－2期，只有PGA指数、HA、C－IV明显上升，但C－IV的上升幅度远低于PGA指数和HA。（4）加以PGA＞4．5或HA＞200μg／L作为判断临界值，则两者判断肝纤维化的敏感性均＞94％，精确性＞91％，特异性＞86％，如两者结合，则分别达到98．3％、95．2％和96．4％。结论：PGA指数和HA均是反映慢性乙型肝炎患者肝内纤维化程度的良好指标，两者联合检测则可达到最大的价值效益比。     

骨髓基质干细胞修复兔关节软骨缺损的实验研究

目的研究以多聚乙醇酸(PGA)为支架的骨髓基质干细胞(BMSCs)复合物修复兔膝关节软骨缺损的情况。方法体外培养扩增的自体BMSCs种植于PGA支架并培养72h,然后将支架-细胞复合物植入兔关节软骨缺损模型。术后12周处死动物,标本行大体观察、组织学检查及Ⅱ型胶原免疫组化染色。结果BMSCs-PGA复合物植入后形成丰富的透明软骨样修复组织,新生软骨无明显退变。对照组主要为纤维组织及软骨下骨修复。结论BMSCs-PGA复合物可修复关节软骨缺损。     

Plasmodium falciparum synthetic LbL microparticle vaccine elicits protective neutralizing antibody and parasite-specific cellular immune responses

Epitopes of the circumsporozoite (CS) protein of Plasmodium falciparum, the most pathogenic species of the malaria parasite, have been shown to elicit protective immunity in experimental animals and human volunteers. The mechanisms of immunity include parasite-neutralizing antibodies that can inhibit parasite motility in the skin at the site of infection and in the bloodstream during transit to the hepatocyte host cell and also block interaction with host cell receptors on hepatocytes. In addition, specific CD4+ and CD8+ cellular mechanisms target the intracellular hepatic forms, thus preventing release of erythrocytic stage parasites from the infected hepatocyte and the ensuing blood stage cycle responsible for clinical disease. An innovative method for producing particle vaccines, layer-by-layer (LbL) fabrication of polypeptide films on solid CaCO₃ cores, was used to produce synthetic malaria vaccines containing a tri-epitope CS peptide T1BT* comprising the antibody epitope of the CS repeat region (B) and two T-cell epitopes, the highly conserved T1 epitope and the universal epitope T*. Mice immunized with microparticles loaded with T1BT* peptide developed parasite-neutralizing antibodies and malaria-specific T-cell responses including cytotoxic effector T-cells. Protection from liver stage infection following challenge with live sporozoites from infected mosquitoes correlated with neutralizing antibody levels. Although some immunized mice with low or undetectable neutralizing antibodies were also protected, depletion of T-cells prior to challenge resulted in the majority of mice remaining resistant to challenge. In addition, mice immunized with microparticles bearing only T-cell epitopes were not protected, demonstrating that cellular immunity alone was not sufficient for protective immunity. Although the microparticles without adjuvant were immunogenic and protective, a simple modification with the lipopeptide TLR2 agonist Pam₃Cys increased the potency and efficacy of the LbL vaccine candidate. This study demonstrates the potential of LbL particles as promising malaria vaccine candidates using the T1BT* epitopes from the P. falciparum CS protein.     

Lipid based nanocarriers: a translational perspective

Over the recent couple of decades, pharmaceutical field has embarked most phenomenal noteworthy achievements in the field of medications as well as drug delivery. The rise of Nanotechnology in this field has reformed the existing drug delivery for targeting, diagnostic, remedial applications and patient monitoring. The convincing usage of nanotechnology in the conveyance of medications that prompts an extension of novel lipid-based nanocarriers and non-liposomal systems has been discussed. Present review deals with the late advances and updates in lipidic nanocarriers, their formulation strategies, challenging aspects, stability profile, clinical applications alongside commercially available products and products under clinical trials. This exploration may give a complete idea viewing the lipid based nanocarriers as a promising choice for the formulation of pharmaceutical products, the challenges looked by the translational process of lipid-based nanocarriers and the combating methodologies to guarantee the headway of these nanocarriers from bench to bedside.     

The use of chitin as a new absorbable suture material—An experimental study

A comparative study of four absorbable suture materials, namely; poly-N-acetylglucosamine (Chitin), polyglycolic acid (PGA), plain catgut and chromic catgut, in terms of strength, elongation, tensile strength retention and tissue reaction, was undertaken. The straight pull strength of USP 3–0 size Chitin was over 2.6 kg, compared with PGA, which was over 3.4 kg and the catguts, which were over 2.0 kg. Chitin showed the lowest elongation among the four. The tensile strength retention (TSR) of Chitin in muscle was 45 per cent at 14 days and 7 per cent at 25 days, which was similar to that of PGA. The TSR of Chitin was maintained by 35 per cent in gastric juice, 97 per cent in bile and 100 per cent in pancreatic juice after immersion for 30 days. The corresponding values for PGA were 54 per cent, 0 per cent and 0 per cent, respectively, whereas both catguts had dissolved within 30 days. The tissue reaction of Chitin was similar to that of PGA, whereas the catguts caused more intense tissue reaction.     

PGA:一种基于最优路径的Ad Hoc网络地理路由算法

本文提出了一种基于最优路径的Ad Hoc网络的地理路由算法PGA及其改进算法H-PGA,该算法在路径的构造、路由、路由恢复各个方面都应用了最优路径路由的概念,较好地解决了地理路由算法中的凹节点问题.在网络节点数n较大的情况下,依然保持很高的报文投递率(n=400、网络度为4时,报文投递率为96%),且实际路径很接近最短路径路径.同时H-PGA路由表的大小与平方根√n成线性关系,单个节点的协议带宽消耗也为O(平方根n),这使得H-PGA可以适用于较大的应用范围.     

New detection method for uropepsinogen (PGA) using isoelectric focusing and immunoblotting techniques

Summary Uropepsinogen (PGA) was isolated and purified from human urine using a column chromatography series. The purified PGA was injected into a rabbit and a PGA-specific antibody was obtained. PGA isozymogen in human urine could be detected reproducibly by immunoblotting using this antibody after isoelectric focusing electrophoresis (IEF) on polyacrylamide gels. This technique may prove to be useful in the genetic study of PGA polymorphism.Supported in part by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan