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Volume ， Issue 2 ， 2002
- Abstract：<正>Objective: To explore the correlation between structure domains and functions of chemokine receptor CXCR4. Methods: After the establishment of wild type chemokine.receptor CXCR4 and CXCR2 expressing cell lines, 5 CXCR4/CXCR2 chimeras, 2 CXCR4 mutants were stably expressed on CHO cell line. Binding activities of all variants with the ligand, recombinant human SDF-1β, signal transduction ability after stimulation and their function as coreceptor for HIV-1 were studied with ligand-binding assay, Cytosensor/ microphysiometry and cell-cell reporter gene fusion assay. Results: Among all 7 changed CXCR4 receptors, 3 chimeras （2444a, 4442, 4122）, and 1 mutant （CXCR4-Tr） bond with SDF-1β in varying degrees, of which only 2444a totally and CXCR4-Tr partially maintain signaling. All changed receptors except for 4222 could act as coreceptors for HIV-1 （LAI） in varying degrees. Conclusion: Several structure domains of CXCR4 are involved in the binding with SDF-1β, among which, N-terminal extracellular domain has h0|43|0Updated：2026-03-12
- Abstract：<正>Objective: To study the effects of the fixed-point mutant on growth cycle and ultrastructure of the Calmodulin fixed-point mutant yeast. Methods: Growth cycle and ultrastructure of the Calmodulin fixed-point mutant yeast were studied by using cytometry and scan electron microscope. Results: After culture at 30’C for 36 h, the content of aneuploidy of the temperature-sensitive recombinant yeast monoploid B（F92+） and E（F89+FH1 + ） strains were 63. 87% and 63. 55%, respectively. These were significantly different from control OP<0. 01) ; The content of the non-temperature-sensitive recombinant yeast monoploid A（F89+） and C（F141+） strains were 100. 00% and 99. 97% , respectively, which were not significantly different from control value （P>0. 05）. Observed by scan electron microscope, the control group, A and C strain’s buds were spherical or oval and those bud-necks were fairly shorter; the B and E strain’s buds were slender, some cell were abnormal and some buds might show spherical or oval. Conclusion: DN0|9|0Updated：2026-03-12
- Abstract：<正>Objective: To explore the spatial distribution of oncomelenia snails in Jiangning County. Methods: Cluster analysis and the Spatial Scan Statistics were performed based on the density of alive-snails in habitats and its rate infected by the 5. japonicum. Results : Although areas of snail habitats and density of the alive-snails in marshland in 2000 are higher significantly than that in mountain areas in Jiangning County, the numbers of habitats in mountain are more than that in marshland and they distributed sporadically. The snail habitats were classified into 4 in marshlands and 3 classes in mountain areas respectively in cluster analysis. Although they are mainly the one with low density of alive and infected snails, we should alert that there are also some habitats with high snail density and infection rate, which is important for the transmission of schis-tosomia. The analysis of Spatial Scan Statistics detected 2 significant spatial aggregations for alive-snail in marshland and 4 in mountain areas0|20|5Updated：2026-03-12
- Abstract：<正>Objective: To study the influence of transfecting antisense expression vector of the first subtype of the monocarboxylate transporter （MCT1） gene into lung cancer cells on pHi regulation, lactate transportation and cell growth. Methods: MCT1 antisense gene recombinant vector was introduced into human lung cancer cell line A549 by electroporation. The transfected A549 cells resistant to G418 were selected. Positive clones were examined by using PCR. The changes of intracellular pH and lactate were examined with spec-trophotometric method. Cell growth was studied with cell growth curve. Results: Intracellular pH and lactate were remarkably decreased in the cells transfected pLXSN-MCT1 in comparison with A549 cells without transfection （P<0. 001）. The growth of A549 cells transfected pLXSN-MCTl was also inhibited remarkably. Conclusion: MCT1 gene may play an important role in pHi regulation, lactate transportation and cell growth in tumor cells.0|6|0Updated：2026-03-12
- Abstract：Objective: To study the angiogenesis effects of adenovirus-mediated gene transfer of VEGF-B on chronic ischemic myocardium. Methods: Domestic pigs underwent thoracotomy and placement of an ameroid constrictor on the circumflex coronary artery. Four weeks later, Ad. VEGF-B, Ad. LacZ or PBS were administrated directly into the myocardium at 10 sites in the circumflex distribution （109 PFU or 100 μl） according to groups. Echocardiography and ex vivo coronary angiography were performed. The injection sites around myocardium were harvested and subjected to histological analysis and immunochemical staining. Results: E-chocardiography assessment 4 weeks after vector administration demonstrated significant improvement of regional wall systolic function. Collateral vessel development assessed by angiography was also significantly greater in Ad. VEGF-B animals than that in control animals. Vascular density analysis revealed a mean of 43±5 neovessels per high-power field in Ad. VEGF-B group versus 19±4 and 17±6 in0|21|0Updated：2026-03-12
- Abstract：<正>Objective: To observe the effects of different gravitational environments on release of prostaglandin E2 in rat calvarial osteoblasts induced by fluid shear stress （FSS） so that to investigate the influence of different gravity on mechanotransduction in osteoblasts. Methods: Osteoblasts were isolated from neonatal rat calvariae and then were set to three groups. Each was cultured in one gravitational environment; 1G terrestrial gravitational environment （control）, simulated weightlessness achieved by using clinostat and 3G gravitational environment achieved by using centrifuge for 60 h, then osteoblasts were treated with 0. 5 Pa or 1. 5 Pa FSS in a flow chamber for 1 h. The release of PGE2 in osteoblasts was determined. Results: In 1G gravitational environment, the release of PGE2 was significantly increased along with the sustaining of FSS treatments （P<0. 01）, but there was no remarkable difference between the responses to 0. 5 Pa FSS and 1. 5 Pa FSS （P>0. 05）. While in simulated weightlessness environ0|6|0Updated：2026-03-12
- Abstract：<正>Objective: To study the genotoxicity and antitumor activity of a Chinese medicinal herb, Triptery-gium Hypoglaucum （Level） Hutch （THH）. Methods: The genotoxicity and antitumor activity of THH were investigated in human promyelocytic leukemia cells on the mutation of hypoxanthine-guanine phosphoribosyl transferase （HPRT） gene by using single cell clone culture, two-way screening counting, multiplex PCR amplification and gel electrophoresis. Results: The results showed that different mutant spectra existed between the spontaneous mutation and induced mutation by THH. Only 7. 7% （1/13） of spontaneous mutants showed deletion mutations, whereas the induced mutants included 46. 6% （27/58） deletions. Mapping of all intra-genic deletion breakpoints showed a random distribution in all 9 exons, but toward the 3’-end of the HPRT gene. Deletion of exon 1 only appeared when whole gene was deleted. Deletions of exon 7/8 and 9 often showed linkage deletions （71. 4%）. Conclusion: THH can induce the mutation, mainly dele0|15|0Updated：2026-03-12
- Abstract：<正>Objective: To study the relationship of the mutation of HBV preS/S gene in HBsAg carrying pregnant women and intrauterine transmission. Methods: Polymerase chain reaction （PCR） was used to amplify HBV preS/S gene from sera of 8 HBsAg carrying pregnant women, 4 women’s neonates infected with HBV, and the other’s neonates non-infected with. The PCR products were cloned and 5 clones were chosen from every woman for DNA sequencing. Results: Heterogeneity of HBV preS/S gene in HBsAg carrying pregnant women having intrauterine transmission was much higher than that from having not intrauterine transmission, and the divergence rate of nucleotide sequences also higher strikingly. Conclusion: High heterogeneity of HBV preS/S gene of HBsAg positive pregnant women may be relative to high rate of intrauterine transmis-0|13|0Updated：2026-03-12
- Abstract：<正>Objective: To know some genetical characterizations of Coxiella burnetii Chinese isolates by comparing the coml gene sequence. Methods: com1 gene sequences of Chinese isolates were amplified, se-quenced, and analyzed by comparing our result and the previous published data. Results: Three different com1 sequences were identified in 7 Chinese isolates. Sequence comparison indicated that the isolates harboring the QpRS plasmid could be defined as a new group and, in addition, the isolates carrying the same plas-mid type showed similar com1 gene sequence. Conclusion: Study suggests that the classification of the group based on the coml gene sequence is highly associated with the plasmid type of the isolates and, however, little related to disease forms and geographical origins of the isolates.0|12|0Updated：2026-03-12
- Abstract：<正>Objective: To study the kinetics and distribution of smooth muscle cell （SMC） proliferation, phe-notypic modulation, and various extracellular matrix （ECM） components accumulation during vein graft remodeling. Methods: Normal vein and vein graft in carotid arteries were examined on d 4, d 7, d 14, d 60 and d180 after bypass grafting with immunohistochemical markers of cellular proliferation （proliferating cell nuclear antigen, PCNA）, cytoskeletal protein production （a-actin SMC）, myosin heavy chain (MHO iso-forms, ECM proteins, and histochemistry （hematoxylin eosin and Elastica-van Gieson stain）. Results: Normal veins demonstrated an extremely low level of cellular proliferation and expressed as adult phenotype SM-Cs in media. After bypass grafting, medial SMCs in the graft appeared to be damaged and began to proliferate on d 4, and subsequently migrated and formed the neointima on d 7. Thereafter, the neointima thickened throughout the 180-day period of the experiment, although the neointimal SMC prolif0|16|0Updated：2026-03-12
- Abstract：<正>Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography （CT） during splenoportography （CTSP）. Methods: Thirty patients refferred for CTSP were included in the study. Attenuation was measured at different time after contrast medium injection, and time-attenuation curves were created. Enhancement characteristics were evaluated, and the parenchyma-to-tumor difference of attenuation were compared. Results: CTSP led to high parenchymal enhancement. The highest enhancement value in the left lobe was （218. 0±53. 2） Hu and （246. 0±60. 2） Hu in the right lobe. The difference between the right and left lobes was statistically significant （P<0. 05）; The parenchyma-to-tumor difference of （65. 3±25. 6） Hu was observed during scanning after injection. Conclusion: The high levels of liver parenchymal enhancement and parenchyma-to-lesion contrast can be achieved within the scanning time with CTSP.0|6|0Updated：2026-03-12
- Abstract：Objective: To study the relationship between Chlamydia pneumoniae （C. pneumoniae） infection and asthma exacerbation. Methods: A prospective study of C. pneumoniae infection was conducted in 75 patients with asthma and 63 patients with respiratory tract infection, and 100 blood donors served as controls. The presence of infection was convinced by the polymerase chain reaction and direct immunofluorescence assay for C. pneumoniae DNA from throat swab specimens and micro-immunofluorescence testing for C. pneu-moniae-specific IgG, IgM and IgA antibodies. Results: Prevalence of specific IgG in asthma patients （81. 3%） was higher than that of the blood donors （68. 0%, P<0. 05） and was not significantly different from respiratory tract infection patients （68. 0%, P>0. 05）. The acute C. pneumoniae infection rate of symptomatic asthma patients （59. 4%） was markedly higher than that of respiratory tract infection patients （34. 9% , P<0. 05）. The average titer of C. pneumoniae IgG instead of IgA in asthma patients (48.0|11|0Updated：2026-03-12
- Abstract：<正>Objective: To describe the characteristic appearance of cavernous hemangioma of the liver （CHL） presented in carbon dioxide digital subtraction angiography （CO2-DSA） and to evaluate the significance of CO2-DSA in the diagnosis of CHL. Methods: Both CO2-DSA and iodinated contrast DSA （IC-DSA） were performed in all 16 patients with CHL, and the angiographic manifestations in the same patients were compared. The image quality was rated by three experienced angiographers, and the complications were also assessed. Results: There was good correlation between angiographers on image quality （R = 0. 73）. Diagnostic images were obtained with both CO2-DSA and IC-DSA in all CHL patients. No difference was noted between IC-DSA and CO2-DSA in visualizing the proper hepatic arteries and its branches （P>0. 05）. CO2-DSA produced better images that clearly described the tumor size, shape and margination than those by IC-DSA （P< 0. 05）, but both demonstrated characteristic appearances of early opacification and persistent0|12|0Updated：2026-03-12
- Abstract：<正>Objective: To observe the central nervous system （CNS） complications among 1083 consecutive renal transplant （RT） recipients. Methods: Systemic analyses of the incidence, time of onset and clinical outcome of CNS complications were conducted in 1083 patients receiving cadaveric RT in Nanfang Hospital during Jan 1992 to Dec 1999. Results: Various CNS complications occurred in a total of 68 RT recipients （6. 28%, 68/1083） with a mortality of （1. 29%, 14/1083）. Of all the 1 083 recipients enrolled in this study, diffuse encephalopathy occurred in 31 cases （2. 86%）, cerebrovascular accidents in 17 （1. 56%）, seizure in 11 （1. 02%） and CNS infection in 9 （0. 83%）. Immusuppressive agents was the major cause for diffuse encephalopathy （93. 5% , 29/31）, and cerebrovascular accidents were associated with a mortality rate of 70. 5% （12/17） and CNS infection with a mortality rate of 22. 22% （2/9）. Most of the complications took place within the first month after RT, especially the first 2 weeks, but the majority of0|7|0Updated：2026-03-12
- Abstract：<正>Objective: To study the correlation of the methylation of the promoters of hMLH1 and hMSH2 with microsatellite instability （MSI） in the tissues of gastric carcinomas. Methods: A total of 68 sporadic cases of gastric carcinoma were studied. Ten specimens of normal gastric mucosa served as control. Methylation of hMLHl and hMSH2 was observed with methylation-specific PCR, and MSI analyzed with PCR-based techniques. Results: No methylation of hMLHl and hMSH2 was found in 10 specimens of normal gastric mucosa. Methylation of hMLHl was detected in 11 cases （16. 2%） of gastric cancers and MSI in at least one locus was found in 17 cases （25%） of the 68 with aid of 5 microsatellite markers, in which eight were MSI-H （≥2loci showed instability） nine MSI-L （only one locus showed instability）, and fifty-one were MSS （no instability at any marker）. The frequency of methylation was significantly high in MSI-H （87. 5%） than in MSI-L （11.1%） and MSS （5. 9%）. CP<0. 01 - 0. 001) but there was no difference of methylatio0|13|1Updated：2026-03-12
- Abstract：<正>Objective: To study the relationship between the polymorphic （CAG）n micro-satellite of human androgen receptor （hAR） gene and prostate cancer （PCa）. Methods: The number of （CAG）n repeats in 107 normal males were measured by a two-step [α-32P]-dCTP incorporated asymmetric polymeric chain reaction （PCR）, and the （CAG）n repeats of both malignant and nonmalignant prostate cells in fixed paraffin-embedded tissue （PET） specimen from 36 case of PCa were determined by sequence analysis. Results: The repeats of polymorphic （CAG） n among normal men ranged from 11 to 29, and the most frequent repeat was 22（18. 69%）, with 23（14. 02%）, 24（10. 28%） and 21（10. 28%） being less frequent. The （CAG）n repeats of malignant prostate cells equaled to that of nonmalignant adjacent prostate tissue cells from the same PET specimen in all 36 PCa, and the （CAG）n repeats in 36 PCa which ranged from 16 to 22 were shorter than that in normal males significantly （P<0. 05）, while no significant difference in （CAG）n repeats among variou0|17|0Updated：2026-03-12
- Abstract：<正>Objectives: To evaluate the barrier function of different skin layers in the process of percutaneous drug absorption. Methods: In vitro permeability via intact or stripped skin of 6 drugs （5-fluorouracil, theo-phylline, hydroquinone, barbital, isosorbide dinitrate and ketoprofen） with a wide span of lipophilicity were investigated in the patch dosage forms. Results: Characteristic parabolic relations was observed between the permeability （Kp, cm/h） of the drugs with different lipophilicity and their LogPc via either intact or stripped skin. However, due to the absence of the stratum corneum, increased Kp ratio for the tested drugs was proportional to their solubility in water other than their LogKp. When isopropyl myristate was used as absorption promoter of the drugs, the parabolic relationship no longer existed. For the intact skin, increase of Kp ratio of the drugs was enhanced resulting from IPM as drug’s LogPc decreased. On the other hand, in the case of stripped skin, this enhancement was positivel0|27|5Updated：2026-03-12
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