1.The establishment of a modified method to evaluate angiogenesis of rat rings in serum free medium
Chinese Journal of Marine Drugs 1994;0(01):-
The establishment of a modified method to evaluate angiogenesis of rat rings in serum-free medium was investigated in this paper. The aorta rings of Wistar rats were embedded in fibrinogen gel in 48 well plates, and cultured in an optimized serum free medium MCDB131. Results indicated that new capillaries spouted on 4th day, and entered into growth phase from 6th day, and peaked on 13th day and remained unchanged thereafter.
2.Determination of poly-mannugluronic acid in urine by electrophoresis
Wei XIA ; Gang DENG ; Meiyu GENG ;
Chinese Journal of Marine Drugs 1994;0(01):-
Objective To establish a cellulose acetate membrane electrophoretic method for separating the exogenous sulfated poly mannuguluronicate(911) from glycosaminoglycans.Methods 911 both in urine and ultrafiltrated urine were extracted with cetylpyridinium chloride (CPC), and then separated by two step electrophoretic method with two different buffer solutions. Results The results indicated that 911 was thoroughly separated from endogenous CSC and DS with its average recovery in urine approximately at 70%. Furthermore, the lowest sensitivity for determination of 911 in aquatic solution was 100 ?g?L -1 , whereas that in urine 250 ?g?L -1 and in ultrafiltrated urine 500 ?g?L -1 . And most importantly 911 in rat's urine was detectable after it's oral administration at dose of 200mg?kg -1 . Conclusions It is the first time for us to conduct the existence of 911 in urine by two step electrophoretic method with two different buffer solutions, suggestive of the feasibility to determine 911 in urine even following it's oral administration.
3.The relationships between senile plaques, neurofibrillary tangles and sulfated polysaccharides
Jinfeng HU ; Meiyu GENG ; Juntian ZHANG ;
Chinese Pharmacological Bulletin 1987;0(01):-
Two aberrant structures, extracellular senile plaques (SP) and intracellular neurofibrillary tangles (NFTs) are the characteristic neuropathological hallmarks of Alzheimers disease (AD). Amyloid ? protein (A?) and hyperphosphorylated tau protein are the major components of SP and NFTs respectively. A large body of evidence has highlighted the pivotal role of sulfated polysaccharides in the amyloidogenesis and formation of NFTs. The underlying mechanisms of the involvement of sulfated polysaccharides in the development of AD were reported to contribute to their high affinity for both A? and tau protein. Sulfated polysaccharides not only promoted the ? secretase cleavage of APP and the increased production of A? and induced the aggregation and deposition of A?, but also facilitated the phosphylation of tau and promoted tau polymerization into fibrils and tangle formation. On the other hand, the neurotrophic effects exerted by sulfated polysaccharides were also demonstrated. These notions were probably due to the inhibition of the formation of A? fibrils or to the counteraction of the abnormal phosphorylation of tau by promoting the protein phosphatase2B activity, which has been speculated to be attributed to the variation in either structural backbone or degree of sulfation or position of sulfation. Putting together, the appropriate structural modification of sulfated polysaccharides may be effective as therapeutic agents for AD.
4.Investigation progress on receptors of saccharides
Benchun MIAO ; Jing LI ; Meiyu GENG
Chinese Pharmacological Bulletin 2003;0(07):-
More and more interest has been put on the investigations of saccharides recent years. Saccharides have a vast number of bioactivities and the immunomodulating effect of saccharides is one of the important mechanisms via which saccharides exert their bioactivities. Saccharides exert their bioactivities mainly by interacting with all kinds of saccharide receptors on cells, followed by a series of signal transduction process. In the present paper, numerous saccharide receptors and the characters of the mutual interaction between saccharides and their receptors are summarized.
5.Integrin and tumor metastasis
Xuelian TANG ; Jing LI ; Meiyu GENG
Chinese Pharmacological Bulletin 2003;0(10):-
Integrin is an important cellular adhesion molecule,which mediates many biologic actions such as cell-cell adhesion or cell-extracellular matrix adhesion.The relationship between integrin and tumor metastasis,as well as the important role of integrin during tumor progress,is reviewed in this article,which gives us the theoretical base for new pathways of cancer treatment.
6.The medical and pharmaceutical applications of low density protein biochips
Yong ZHOU ; Meiyu GENG ; Guanhua DU
Chinese Pharmacological Bulletin 1986;0(04):-
Protein biochips industry has been making significant progress recently. It played a role in the discovery-oriented proteomics, but now the research emphasis turns to the study of important functional proteins. The emergence of the low density protein biochip technique facilitated this study conversion. This technology has advantages of low cross-reaction, high signal intensity and good precision. This paper reviewed various medical and pharmaceutical applications of the low density protein biochips in disease diagnostics and monitoring, drug discovery and testing, as well as molecular interaction and signaling pathways.
7.Glycosylations and cancer cell cycle
Yunxue ZHAO ; Jing LI ; Meiyu GENG
Chinese Pharmacological Bulletin 2003;0(08):-
It is well known that oligosaccharides in glycoproteins and glycolipids play crucial roles in a variety of cellular functions, such as proliferation, differentiation, and intercellular communications. The oligosaccharides of cell are increasingly being recognized as one of the most prominent biochemical alterations associated with malignant transformation and tumorigenesis. Glycosylations in different cell cycle and cell growth periods are significantly distinct, and these differences affect the cell cycle progression. In the past decades, along with the advances in genomics and proteomics, the functional significance of cancer-associated changes in glycosylation has been revealed. Eukaryotic organisms depend on an intricate and evolutionary conserved cell cycle to control cell devision. Mistakes in cell cycle process lead to cancer. This review highlights the relations between cell cycle and glycosylation changes in cancer cells.
8.The role of protein kinase C in cancer and the progress of inhibitors targeting protein kinase C
Li LI ; Jing LI ; Meiyu GENG
Chinese Pharmacological Bulletin 1986;0(06):-
Protein Kinase C(PKC) plays a key role in carcinogenesis and metastasis,therefore,PKC is the potential molecular target to develop the treatments of cancer.Currently several PKC inhibitors have entered the clinical research stage,at the same time they also bring new challenges to research and development of anti-cancer drugs targeting PKC.The article will review the recent role of PKC in cancer and the progress of inhibitors targeting PKC.
9.DNA topoisomerase and antitumor
Xiaomei MO ; Jing LI ; Meiyu GENG
Chinese Pharmacological Bulletin 1987;0(01):-
DNA topoisomerase is a basic enzyme in eucaryon and prokaryotic cells, which distributes in cell nucleus generally. DNA topoisomerase plays important roles in the process of duplication, transcription, translation, recombination and chromosome monomer isolation to control, keep and modify the DNA topology. It is reported that DNA topoisomerase has a high expression level, which related with the mechanism of many antitumor drugs.
10.The relationship between sulfated polysaccharides and atherosclerosis
Jinfeng HU ; Meiyu GENG ; Juntian ZHANG
Chinese Pharmacological Bulletin 1987;0(02):-
The atherogensis was involved in a complex pathological process. Injury to endothelial cells of blood vessels was confirmed to be the initial stage of this process. Migration to subendothelial layer and accumulation and proliferation of smooth muscle cells were attributed to various cytokines and adhesive molecules secreted by activated endothelial cells, subsequently resulting in aggregation of lymphocytes, platelets, monocytes and macrophages in the intima of artery. These cellular components ultimatedly led to the formation of a mature atherosclerotic plaque. It's quite acknowledged that a better understanding of the atherogenic events might promise us the development of new chemical entities of anti-atherosclerotic therapies. A large body of evidence has demonstrated that sulfated polysaccharides played a critical role in the development of atheroscle- rosis. The underlying mechanisms of the antiatherosclerotic activity of sulfated polysaccharides were reported to contribute to protecting against endothelial cells injury, inhibiting migration and proliferation of vascular smooth muscle cells, and reducing the adhesion of inflammatory Cells, platelets and lymphocytes. And also, the prevention of complement activation by sulfated polysaccharides could not be excluded. On the other hand, the promoting effects of sulfated polysaccharides atherosclerosis was also reported. It's therefore concluded that the relationships between atherioscierosis and sulfated polysaccharides remained to be further elucidated.