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Volume ， Issue 1 ， 1999
- Abstract：Objective. DNA modification fixed as mutations in the cells may be an essential factor in the initiation step of chemical carcinogenesis. In order to explore the mechanism of gene mutation and cell transformation induced by glycidyl methacrylate （GMA）, the current test studied the characteristics of GMA DNA adducts formation in vitro. Methods. In vitro test, dAMP, dCMP, dGMP, dTMP and calf thymus DNA were allowed to react with GMA （Glycidyl Methacrylate）. After the reaction, the mixtures were detected by UV and subjected to reversed phase HPLC on ultrasphere ODS reversed phase column, the reaction products were eluted with a linear gradients of methanol （solvent A） and 10mmol/L ammonium formate, pH5 0 （solvent B）. The synthesized adducts were then characterized by UV spectroscopy in acid （pH1 0）, neutral （pH7 2）, alkaline （pH11 0） and by mass spectroscopy. Results. The results showed that GMA could bind with dAMP, dCMP, dGMP and calf thymus DNA by covalent bond, and the binding sites were specific （N 6 of adenine, N 3 of cytosine）. Meanwhile, a main GMA DNA adduct in the reaction of GMA with calf thymus DNA was confirmed as N 3 methacrylate 2 hydroxypropy1 dCMP. Conclusions. GMA can react with DNA and /or deoxynucleotide monophosphate and generate some adducts such as N 6 methacrylate 2 hydroxypropyl dAMP and N 3 methacrylate 2 hydroxypropyl dCMP, ets. Formation of GMA DNA adducts is an important molecular event in gene mutation and cell transformation induced by GMA.4|16|1Updated：2024-04-10
- Abstract：Ｂｉｎｓｗａｎｇｅｒ′ｓｄｉｓｅａｓｅ（ＢＤ），ａｆｏｒｍｏｆｖａｓｃｕｌａｒｄｅ－ｍｅｎｔｉａ，ｉｓｃｈａｒａｃｔｅｒｉｚｅｄｐａｔｈｏｌｏｇｉｃａｌｙｂｙｄｉｆｕｓｅｄｅ－ｍｙｅｌｉｎａｔｉｏｎａｎｄｍｕｌｔｉｐｌｅｓｍａｌｉｎｆａｒｃｔｓｉｎｔ...4|5|0Updated：2024-04-10
- Abstract：ＣａｓｅＮｏ．Ａｇｅ／ｓｅｘＨｉｓｔｏｌｏｇｙＤｅｇｒｅｅｏｆｄｉｆｅｒｅｎｔｉａｔｉｏｎＣｌｉｎｉｃａｌｓｔａｇｅＴｕｍｏｒｓｉｚｅ（ｃｍ）Ｋａｒｙｏｔｙｐｅ３５３／ＦＡｄｅｎｏｃａｒｃｉｎｏｍａＭｏｄｅｒａｔｅＴ３Ｎ２Ｍ０２×４×１３９＜２ｎ＞，...4|24|0Updated：2024-04-10
- Abstract：Gene therapy is one of several approaches that are being tested in the search for an effective anti HIV treatment. In this strategy, a “resistant” gene would be introduced into target cells, rendering them resistance to the infection of HIV. The HIV 1 Tat protein transactivate HIV 1 gene expression at the transcriptional level by interacting with its response element（TAR） in the long terminal repeat（LTR）. Previously, we have shown that antisense polyTAR Core RNAs can inhibit the transactivation of HIV 1 Tat protein in transiently transfected Jurkat cells. To determine whether this antisense polyTAR Core RNAs could inhibit HIV 1 replication in CD 4+ T cells, we transfected the antisense polyTAR Core gene to MT4 cells and challenged them with HIV 1 SF33 strain. Levels of HIV 1 p24gag antigen were reduced more than 4 fold in cultures of the transduced MT4/LR cells infected with HIV 1SF33 strain. In contrast, cultures of nontransduced MT4 cells and control LX vector transduced MT4/LX cells infected with the same viruses had high levels of HIV 1 p24gag. Our work showed that antisense polyTAR Core RNAs were able to inhibit HIV 1 replication in CD 4+ T cells, and could be used as resistance gene in further studying for gene therapy against HIV 1.4|12|0Updated：2024-04-10
- Abstract：ＣａｔｈｅｐｓｉｎＤ（ＣＤ），ａｗｉｄｅｌｙｅｘｐｒｅｓｓｅｄａｓｐａｒｔｙｌｌｙｓｏｓｏｍａｌａｃｉｄｉｃｐｒｏｔｅａｓｅ，ｈａｓｂｅｅｎｒｅｐｏｒｔｅｄｔｏｐｌａｙａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｔｕｍｏｒｉｎｖａｓｉｏｎａｎｄｍｅｔａｓｔａｓ...4|6|0Updated：2024-04-10
- Abstract：The acid soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash out materials from rats, rabbits, pigs, and humans manifested strong bactericidal activity against E.coli in vitro. The ultrafiltrate of the human material, which contained two major peptides with apparent molecular masses of 6 7 kD and 8 5 kD, respectively, showed potent bactericidal activity against E. coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus sanguis.Three antibacterial polypeptides （PiBPs） were purified from the porcine material. The molecular masses of PiBP 5, PiBP 11 and PiBP 25 were 5773.3 Da, 11127.8 Da and 25073 Da, respectively. PiBP 5 was unusually rich in glycine, serine and threonine residues（20 0, 16 3 and 10 4 mo1%, respectively）, and N terminal amino acid sequencing revealed that PiBP 5 was homologous （83 3% identity in an 18 residue overlay） to the “tail” of human cytokeratin 7. Although the amino acid compositions of PiBP 11 and PiBP 25 were established, both had blocked N termini and primary sequence data were not obtained. These results provided evidence indicating that the presence of peptides in the bladder mucosa could enable it to kill adherent bacteria.6|7|1Updated：2024-04-10
- Abstract：The role of bivalent cations and choline in ATP induced apoptosis via P2Z purinoceptor was investigated in human leukemic lymphocytes. In vitro exposure of leukemic lymphocytes with P2Z receptors to 1 mmol/L ATP or 0 1 mmol/L benzoylbenzoic ATP（BzATP） for 8 h in the presence of choline, 1 mmol/L Mg 2+ or other bivalent cations, and ATP induced DNA breaks, associated with apoptosis were quantified by TdT assay. We observed that （1） Extracellular Mg 2+ or Ca 2+ stimulated ATP induced DNA fragmentation in a dose dependent manner, and the compatible evidence was provided by the inhibition of ATP induced DNA fragmentation in the present of EGTA or EDTA; （2） ATP induced DNA fragmentation was completely inhibited by 1 mmol/L Zn 2+ ;（3）ATP induced DNA breaks were not affected by Ba 2+ , Sr 2+ , Co 2+ when they were substituted for extracellular Mg 2+ or Ca 2+ ;（4）Choline, an inhibitor of phospholipase D（PLD） stimulated by ATP through P2Z receptor in human lymphocytes, was also a partial inhibitor of ATP induced DNA fragmentation, and the results were confirmed by flow cytometric analysis （FCA）; （5）ATP induced DNA fragmentation was completely obliterated when the temperature was lower than 10℃. These results suggest that the endonuclease and PLD may be involved in ATP induced apoptosis in human lymphocytes via P2Z receptor.4|11|0Updated：2024-04-10
- Abstract：A cosmid construct μLCRAγψβδβ were induced into mouse erythroleukemia cell lines 585 that expresses murine adult globin only and MEL GM 979 that expresses both murine embryonic and adult globins.Similar patterns of human globin gene expression were displayed in the two MEL cell lines transfected with the construct.Inducible expression of the Aγ and β gene was observed during induced cell differentiation.However,the expression level of the Aγ globin gene is much higher than that of the β globin gene in either uninduced or induced MEL transformants.No γ to β switching happened in the stable MEL transformants following a continuous culture.The much more effective enhance of the μLCR on the Aγ globin gene than that on the β globin gene is resulted probably from the fact that the distance between the LCR and the β globin gene is much longer than that between the LCR and the Aγ globin gene in the construct,in comparison with other constructs containing HS2 or μLCR linked to both of γ and β globin genes in different order.Two suggestions can be derived from these results:1) A competition between the γ and β globin gene for interaction with the LCR may indeed present,but only an enough long distance difference between the LCR to the γ and to the β gene can effectively influence the competition;2) Unlike transgenic mice,MEL cells are incapable of reconstructing the regulatory information involved in developmental control when it is provided by a fragment of the β globin gene cluster with limited length.4|11|1Updated：2024-04-10
- Abstract：S 3 1 is a simplified synthetic analogue of the active principle of Salvia miltiorrhioza. Electron spin resonance spectrometry using 5,5′ dimethyl 1 pyrroline N oxide as a scavenger of free radicals indicated that 200 μg/ml of S 3 1 scavenged 1,1 diphenyl 2 picrylhydrazyl radicals completely. 25μg/ml of this compound quenched 100% of superoxide anion and a concentration of 250 μg/ml of S 3 1 quenched 63% of hydroxyl radicals. It was also shown that 3 56 mg/ml of S 3 1 could inhibit lipid peroxidation in microsome fraction from rat liver induced by FeSO 4 and cysteine. These results show that S 3 1 is an effective antioxidant by scavenging free radicals.4|8|0Updated：2024-04-10
- Abstract：Objective.The present study investigated the role of endogenous carbon monoxide（CO）in the pathogenesis of neointimal formation induced by balloon injury in rat. Method.Endothelial denudation of the left common carotid artery of rat was carried out by three passages of a Fogarty 2F balloon catheter.DNA,collagen and elastin contents of each intima media were estimated;and heme oxygenase（HO）activity and CO production in vascular smooth muscle cell（VSMC）were measured after administration of HO inhibitor. Result.Our data showed that neointima occurred in the rat on day 7 and day 21 after balloon injury,and at the same time HO activity and CO production in VSMC were markedly increased Administration of HO inhibitor,zinc deuteroporphyrin 2,4 bisglycol（ZnDPBG）,could effectively inhibit HO activity and CO production,significantly enhance neointimal formation（aortic intima/media ratio were 21 4±1 8% vs 17 6±2 0%,P<0 05 on day 7;and 30 5±2 4% vs 23 0±2 2%,P<0 01 on day 21,respectively,compared with balloon alone group）. Conclusion.We concluded that 1)inhibition of CO production may enhance neointimal formation induced by endothelial denudation,implying endogenous CO play an protective role in response to vascular injury,and 2)induction of HO activity may be applied clinically for preventing restenosis after angioplasty.4|13|0Updated：2024-04-10
- Abstract：Objective. To ascertain the relationship between the Ala54Thr variation of FABP2 gene and general as well as regional adipose tissue depots. Subjects. 165 subjects, in which 86 were subjects with normal glucose tolerance （NGT） [age 54 45±9 80, male/female 1 05,body mass index （BMI）26 48±4 01] and 79 were subjects with non insulin dependent diabetes mellitus （NIDDM）（age 55 86±10 00,male/female 1 08,BMI 26 75±3 30）. Design and measurements. An association study of FABP2 Ala54Thr variation detected by PCR/HhaI digestion with general and regional adipose tissue depots determined by BMI and magnetic resonance imaging [abdominal subcutaneous and visceral adipose tissue area （SA and VA） and femoral subcutaneous adipose tissue area （FA）]. Results. The geneotype and allele frequencies of FABP2 Ala54Thr variation in Chinese were quite close to the frequencies in American Caucasians and Pima Indians reported in the literature. Significant difference in genotype frequency distribution was observed between FA subgroups comparisons （FA≥75cm 2 versus FA<75cm 2 ）in NIDDM subjects （X 2 =11 460,P=0 003）,with significantly increased in Thr54 carrier[Thr54（+）]genotype frequency and Thr54 allele frequency in NIDDM subject with FA<75cm 2 （odd ratio for genotype was 4 62,X 2 =10 112,P=0 001;and for allele=2 36,X 2 =5 379,P=0 020）.The FA in NIDDM Thr54（+）subgroup was significantly lower than that in subjects with NIDDM Thr54（ ）sugroup（61 19±21 51cm 2 versus 75 36±31 70cm 2 ,P=0 021）. Stepwise regression analysis revealed that FABP2 Thr54 genotype variation was an independent factor contributing to the variation of FA in NIDDM（P=0 003）. Conclusion. FABP2 is associated with regional adipose tissue depot.The decreased femoral subcutaneous adipose tissue depot in NIDDM subjects is related to FABP2 Thr54 variant.4|27|1Updated：2024-04-10
- Abstract：A sero epidemiological survey on 1 833 healthy residents was carried out in 6 villages of a leprosy high endemic area in Wenshan and Guangnan counties, Yunnan Province. The part of the residents with initially antibody positive as well as the part of residents with initially antibody negative have been followed up for 3 consecutive years by serology and clinical examination for studying kinetic changes of antibody to M.leprae and its relation with clinical disease. The results showed that the rates of subclinical infection of leprosy in a high endemic area are different from village to village, and the risk of developing clinical disease does not associate with subclinical infection rate. It correlates with the number of cured accumulative leprosy cases and active cases within the village. The authors consider that in leprosy high endemic villages, especially those cropped up new multi bacillary leprosy cases frequently in recent years, it may be helpful to use serology to detect early leprosy cases.4|5|1Updated：2024-04-10
- Abstract：The present study identified the properties of porins in the outer membrane in Pseudomonas aeruginosa,and showed the role of outer membrane in determining imipenem diffusion in Pseudomonas aeruginosa The molecular weight of the major outer membrane protein was analyzed by SDS PAGE The purification of the porins in Pseudomonas aeruginosa was achieved by DEAE ion exchange HPLC The purified outer membrane proteins were reconstituted with phosphatidylcholine and dicetylphosphate into membrane vesicles, and were tested by the liposomes swelling method for the diffusion of imipenem The permeability assay showed that OprC （70 kD）, OprD 2 （46kD）, and OprE（43 kD） were the channel forming proteins But only OprD 2 was thought to be the likely route of imipenem diffusion4|4|1Updated：2024-04-10
- Abstract：Objective To study the performance of free nerve graft with vascular implantation Material and method Three groups of rats were used A 10 mm nerve defect was made in the sciatic nerve It was repaired respectively with vascularised nerve graft（VNG）, free nerve graft with vascular implantation（NGV） or free nerve graft（NG） Before 30 days the revascularisation of the nerve graft was assessed;at 2 to 3 month regeneration of nerve was evaluated Histochemical staining, vascular morphology and electrophysiological examination were undertaken Result and conclusion The number of regenerated blood vessels in VNG and NGV was significantly increased than that in NG before 30 days The ratio of regenerated nerve fiber area and conduction velocity in the first two groups were much better than those in NG at 2 to 3 months4|31|0Updated：2024-04-10
- Abstract：Purpose. This paper studies the tumour necrosis factor （TNF） levels in aqueous humor after traumatic cataract extraction and posterior chamber （PC） intraocular lens （IOL） implantation in rabbits,and discusses the effect of TNF on postoperative anterior ocular inflammation. Methods. Twenty seven pigmented rabbits were divided into three groups: for the first group, the IOL were placed in the capsular bag after traumatic cataract extraction; for the second, the Extracapsular cataract extraction without IOL implantation; and for the third, the control group without surgical intervention. On the 1st, 3rd, 7th and 14th day postoperatively, aqueous humor samples were obtained. A modified double antibodies indirect sandwich ELISA was used to detected for the presence of TNF. The data were studied by means of analysis of variance in SAS software. Result. The TNF level was increased in aqueous humor and reached its maximum on the 1st postoperative days after traumatic cataract extraction and PC IOLs implantation, and the TNF levels are significantly higher （P<0 05） on the 1st, 3rd, 7th and 14th day postoperatively in traumatic cataract extraction and PC IOL implanted group than that in the non surgical intervention group and extracapsular cataract extraction group. Conclusions. The increase of TNF levels had a close relationship with presence of the IOL itself which induces the secretion of TNF. This suggested that TNF as the principal mediators of immunological and inflammatory responses, so that may play critical role in anterior ocular inflammative response after traumatic cataract extraction and IOL implantation.4|11|3Updated：2024-04-10
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