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Kim PM, Allen C, Wagener BM, Shen Z, Nickoloff JA. Overexpression of human RAD51 and RAD52 reduces double-strand break-induced homologous recombination in mammalian cells. Nucleic Acids Res 2001; 29:4352-60. [PMID: 11691922 PMCID: PMC60192 DOI: 10.1093/nar/29.21.4352] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Double-strand breaks (DSBs) can be repaired by homologous recombination (HR) in mammalian cells, often resulting in gene conversion. RAD51 functions with RAD52 and other proteins to effect strand exchange during HR, forming heteroduplex DNA (hDNA) that is resolved by mismatch repair to yield a gene conversion tract. In mammalian cells RAD51 and RAD52 overexpression increase the frequency of spontaneous HR, and one study indicated that overexpression of mouse RAD51 enhances DSB-induced HR in Chinese hamster ovary (CHO) cells. We tested the effects of transient and stable overexpression of human RAD51 and/or human RAD52 on DSB-induced HR in CHO cells and in human cells. DSBs were targeted to chromosomal recombination substrates with I-SceI nuclease. In all cases, excess RAD51 and/or RAD52 reduced DSB-induced HR, contrasting with prior studies. These distinct results may reflect differences in recombination substrate structures or different levels of overexpression. Excess RAD51/RAD52 did not increase conversion tract lengths, nor were product spectra otherwise altered, indicating that excess HR proteins can have dominant negative effects on HR initiation, but do not affect later steps such as hDNA formation, mismatch repair or the resolution of intermediates.
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327
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Newburg DS, Shen Z, Warren CD. Quantitative analysis of human milk oligosaccharides by capillary electrophoresis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 478:381-2. [PMID: 11065092 DOI: 10.1007/0-306-46830-1_37] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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328
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Shen Z, Wu M, Elson P, Kennedy AW, Belinson J, Casey G, Xu Y. Fatty acid composition of lysophosphatidic acid and lysophosphatidylinositol in plasma from patients with ovarian cancer and other gynecological diseases. Gynecol Oncol 2001; 83:25-30. [PMID: 11585410 DOI: 10.1006/gyno.2001.6357] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE We previously reported that plasma levels of total lysophosphatidic acid (LPA) represented a potential biomarker for ovarian cancer and other gynecological cancers [1]. However, total LPA is composed of different LPA species with distinct fatty acid chains. The major objective of the current study, therefore, was to determine whether one or more specific fatty acid LPA species was associated with disease or disease staging. If this was determined, these species could be useful in further improving the sensitivity and/or specificity of this biomarker for the diagnosis and/or prognosis of the disease. Because lysophosphatidylinositol (LPI) co-migrates with LPA, this study represents the analysis of combined molecular species from both lysolipid classes. METHODS The patient population, sample collection, and analyses have been reported previously [1]. Lipids were hydrolyzed from the LPA band on thin-layer chromatography plates. The following individual fatty acid species were analyzed by gas chromatography: palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), arachidonic acid (20:4), and docosahexaenoic acid (22:6). The LPA/LPI fatty acid composition levels were analyzed and compared with disease status. RESULTS Distinct plasma LPA/LPI fatty acid chain species were not associated with ovarian or other gynecological cancers, compared to patients with benign gynecological disease or healthy controls. However, an increased presence of unsaturated fatty acids in plasma LPA/LPI was found in patients with late-stage or recurrent ovarian cancer and possibly with other gynecological cancers. CONCLUSIONS Analysis of individual fatty acid species present in plasma LPA/LPI do not appear to enhance the sensitivity or specificity of total LPA/LPI as a marker for gynecological cancer detection. However, our results suggest that increased LPA/LPI species with unsaturated fatty acid chains may be associated with late-stage or recurrent ovarian cancer.
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Whary MT, Cline J, King A, Ge Z, Shen Z, Sheppard B, Fox JG. Long-term colonization levels of Helicobacter hepaticus in the cecum of hepatitis-prone A/JCr mice are significantly lower than those in hepatitis-resistant C57BL/6 mice. Comp Med 2001; 51:413-7. [PMID: 11924800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Helicobacter hepaticus infection causes hepatitis in A/JCr mice but mild or no disease in C57BL/6 mice. Colonization of H. hepaticus in the cecum of experimentally infected A/JCr and C57BL/6 mice was quantified by use of real-time polymerase chain reaction (PCR) analysis with primers for the H. hepaticus cdtB gene and mouse 18srRNA. Eight-week-old mice were experimentally (n = 48) or sham (n = 24) infected with H. hepaticus, then were necropsied 6 months after infection. Liver specimens from experimentally infected mice had negative results of PCR analysis for H. hepaticus; thus, real-time quantification was not attempted. Quantitative PCR analysis of H. hepaticus in cecal specimens indicated that C57BL/6 mice were colonized to a greater extent than were A/JCr mice (P < 0.006). Appreciable typhlitis was not observed, but was consistent with that of previous reports; A/JCr mice developed more severe parenchymal necrosis, portal inflammation, and phlebitis in the liver (P < 0.0001), with mild disease observed in infected C57BL/6 mice. Thus, hepatitis in A/JCr mice caused by H. hepaticus infection is associated with significantly lower colonization levels of H. hepaticus in the cecum, compared with those of hepatitis-resistant C57BL/6 mice. Host responses of A/JCr mice that limit cecal colonization with H. hepaticus may have important roles in the pathogenesis of hepatic lesions.
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330
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Yu H, Shi Y, Zhang Y, Yang S, Shen Z. [Introduction of Vitreoscilla hemoglobin gene in a recombinant E. coli for PHB production]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2001; 41:548-52. [PMID: 12552801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Vitreoscilla hemoglobin gene (vgb) was introduced into the recombinant Escherichia coli VG1(pTU14) for production of poly-beta-hydroxybutyrate (PHB), in order to enhance the oxygen uptake of strain from molecular level and to solve the problem of oxygen limitation in process of fermentation. The carbon monoxide difference spectra analysis of Vitreoscilla hemoglobin (VHb) showed that vgb could be successfully expressed in VG1 (pTU14), and this expression was under the regulation of dissolved oxygen (DO). The higher amounts of VHb could be got correspond to the lower level of DO. Because of the introduction of vgb, cell growth and PHB accumulation of VG1 (pTU14) were all strongly promoted during the process of batch culture.
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331
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Shen Z, Zhuang Z, Huang H, Zhang J. [Effect of Ce3+ on reactive oxygen species in cells]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2001; 30:275-7. [PMID: 12561591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The effect of Ce3+ on the content of (reactive oxygen species ROS) in hepatocytes and V79 cells was studied with microfluorometry. The results showed that Ce3+ could enhance the concentration of ROS in hepatocytes in high dose and reduce the concentration of ROS in low dose. These results suggested that Ce3+ might decrease the damage of lipid peroxidation and DNA in low dose and might increase the damage of lipid peroxidaion and DNA in high dose.
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Shen Z, Feng Y, Dewhirst FE, Fox JG. Coinfection of enteric Helicobacter spp. and Campylobacter spp. in cats. J Clin Microbiol 2001; 39:2166-72. [PMID: 11376052 PMCID: PMC88106 DOI: 10.1128/jcm.39.6.2166-2172.2001] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
During a 6-year period, 64 of 227 commercially reared cats had microaerobic bacteria isolated from their feces. All the isolates were initially identified as Campylobacter-like organisms based on biochemical and phenotypic characteristics. DNA extractions from 51 of these isolates were subjected to PCR using primers specific for Helicobacter spp. and Campylobacter spp. Of the isolates, 92% (47 of 51 isolates) were positive for Campylobacter spp., 41% (21 of 51 isolates) were positive for Helicobacter spp., 33% (17 of 51 isolates) were positive for both genera, 59% (30 of 51 isolates) were positive only for Campylobacter spp., and 8% (4 of 51) were positive only for Helicobacter spp. Sixteen of the 47 Campylobacter-positive cultures were positive for more than one Campylobacter spp. Based on a species-specific PCR assay, 83% of the isolates were identified as Campylobacter helveticus, 47% of the isolates were identified as Campylobacter upsaliensis, and 6% of the isolates were classified as Campylobacter jejuni. The 1.2-kb PCR products of the 16S rRNA genes of 19 Helicobacter species isolates were subjected to restriction fragment length polymorphism (RFLP) analysis. Of the five different RFLP patterns obtained, two clustered with Helicobacter ("Flexispira") taxon 8, one clustered with Helicobacter bilis, one clustered with Helicobacter canis, and the remaining pattern was closely related to a novel Helicobacter sp. strain isolated from a woodchuck. The sequence data for the 16S rRNA genes of 10 Helicobacter spp. validated the RFLP-based identification of these isolates. This study demonstrated that biochemical and phenotypic characteristics of microaerobic organisms in cat feces were insufficient to characterize mixed Helicobacter and Campylobacter infections. Molecular structure-based diagnostics using genus- and species-specific PCR, RFLP analysis, and 16S rRNA sequence analysis enabled the identification of multiple microaerobic species in individual animals. The clinical relevance of enteric Helicobacter and Campylobacter coinfection in cats will require further studies.
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333
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Shen Z, Shen H. [Determination of nickel in artificial cream by flame atomic absorption spectrometry]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2001; 21:567-568. [PMID: 12945297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper describes a new method for the determination of nickel in artificial cream by flame atomic absorption spectrometry. Compared with the others, the process of sample treatment by HNO3-H2SO4 is simple, and the operation is easy. The results show that the method offers good precision and accuracy. The relative standard deviation is 3.04% and the rate of recovery is 97.7%.
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334
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Cui J, Shen K, Shen Z, Jiang F, Shen F. [Relationship of vitamin D receptor polymorphism with breast cancer]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2001; 18:286-8. [PMID: 11484168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To detect the association between vitamin D receptor polymorphism and breast cancer. METHODS Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method was used. Two restriction fragment length polymorphisms in the 3'region of vitamin D receptor (VDR) gene, Taq I and Apa I, were tested for association with breast cancer risk in 86 females with breast cancer and 134 healthy female controls. RESULTS Allele frequencies of the 3'Taq I polymorphism showed a significant association (P=0.0004, OR:5.39,CI:1.81-17.20). The further study of genotype found the association of Tt, tt with breast cancer. The haplotype analysis of Apa I and Taq I showed a linkage disequilibrium between t-allele and A-allele. The frequency of tA haplotype was higher in breast cancer patients than in controls (P=0.001), indicating that tA haplotype is associated with breast cancer. The alleles and haplotype of the two loci had not any difference among the clinical subgroups. CONCLUSION There is association between vitamin D receptor polymorphism and breast cancer.
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335
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Shen Z, Shang Y, Zhu W. [The prevalence of renal artery stenosis in patients with coronary artery disease]. ZHONGHUA NEI KE ZA ZHI 2001; 40:521-4. [PMID: 11718051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
OBJECTIVE To understand the prevalence of renal artery stenosis(RAS) in patients with coronary artery disease(CAD) and the relations among coronary artery disease, renal artery stenosis, hypertension and renal insufficiency. METHODS 280 patients with coronary artery disease or suspected coronary disease were carried out renal artery angiography after coronary angiography over 1 year period. RESULTS Of the total patient cohort, 43(15.3%) had significant RAS (> or = 50%), 3(1.0%) were obstructed and 14 (5.0%) were bilateral. 36 (19.1%) were diagnosed as having significant RAS among 188 CAD patients. 7 patients with significant RAS were found among 92 patients without significant coronary artery stenosis, all of them were found in the group of 22 patients with mild coronary artery atheroscloresis. The prevalence of significant RAS was 19.6% and 7.9% as referred to with or without hypertension, P < 0.05. 10 patients (55.6%) had significant RAS in 18 patients with mild renal insufficiency as compared to 33 patients (12.6%) had significant RAS in 262 patients with normal renal function, P < 0.05. In the subgroup of CAD, the prevalence of significant RAS were 15.3%, 17.1%, 25.4% in single vessel disease, two vessel disease and triple vessel disease patients, P < 0.05. 35 patients (81.4%) had hypertension among these 43 patients with RAS with 24 (56.0%) patient's blood pressure difficult to control. CONCLUSIONS RAS is a frequent finding in patients with CAD, especially in triple vessel disease patients. Hypertension is closely related to RAS, it should be the risk factor of RAS, and can be the clinical manifestation of RAS. CAD patients with renal insufficiency but without history of chronic glomerulonephritis may indicate RAS.
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336
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Lu YH, Fun HK, Chantrapromma S, Razak IA, Shen Z, Zuo JL, You XZ. A mixed-valence manganese(III)-manganese(IV) di-mu-oxo complex, [(cyclam)MnO]2(ClO4)2(NO3). Acta Crystallogr C 2001; 57:911-3. [PMID: 11498610 DOI: 10.1107/s0108270101008617] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2001] [Accepted: 05/25/2001] [Indexed: 11/10/2022] Open
Abstract
The title dinuclear di-mu-oxo-bis[(1,4,8,11-tetraazacyclotetradecane-kappa(4)N)manganese(III,IV)] diperchlorate nitrate complex, [Mn(2)O(2)(C(10)H(24)N(4))(2)](ClO(4))(2)(NO(3)) or [(cyclam)MnO](2)(ClO(4))(2)(NO(3)), was self-assembled by the reaction of Mn(2+) with 1,4,8,11-tetraazacyclotetradecane in aqueous media. The structure of this compound consists of a centrosymmetric binuclear [(cyclam)MnO](3+) unit, two perchlorate anions and one nitrate anion. While the low-temperature electron paramagnetic resonance spectra show a typical 16-line signal for a di-mu-oxo Mn(III)/Mn(IV) dimer, the magnetic susceptibility studies also confirm a characteristic antiferromagnetic coupling between the electronic spins of the Mn(IV) and Mn(III) ions.
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337
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Dong Y, Shen H, Shen Z, Lin J. [Determination of trace as in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2001; 21:563-564. [PMID: 12945295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A new method has been developed for the determination of trace metal As in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization. The method is convenient to determine element in water. The results show that the method has good precision and accuracy. The detection limit is 2 ng.L-1 for As. The relative standard deviation is 5.4%-6.1%, and the rates of recovery is 87.5%-115%. This method has been applied to the determination of health-giving drink with satisfactory results.
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338
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Shen Z, Warren CD, Newburg DS. Resolution of structural isomers of sialylated oligosaccharides by capillary electrophoresis. J Chromatogr A 2001; 921:315-21. [PMID: 11471815 DOI: 10.1016/s0021-9673(01)00872-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The resolution of structural isomers in mixtures of oligosaccharides is often challenging. Capillary electrophoresis was employed to separate three sets of structural isomers of sialylated oligosaccharides found in human milk and bovine colostrum. Different running buffers were necessary to achieve optimal baseline resolution. To resolve 3'- and 6'-sialyllactoses, 0.2 M aqueous sodium phosphate containing 40% methanol as an organic modifier was used as a running buffer. To resolve 3'- and 6'-sialyllactosamines, 0.4 M aqueous sodium phosphate without organic modifier was used. Baseline resolution of sialyllacto-N-tetraose-a and -b and sialyllacto-N-neotetraose-c was achieved with a 0.4 M Tris-HCl buffer containing 250 mM sodium dodecyl sulfate and 10% methanol as the organic modifier. Thus, each of these sets of structural isomers of sialylated oligosaccharides required a unique running buffer with respect to buffer type, concentration, pH, presence of organic modifiers, and surfactants. Similar electrophoresis conditions may be useful for resolving and analyzing other structural isomers of acidic oligosaccharides by capillary electrophoresis.
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339
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Wang H, Shen Z. [Experimental research of laser-induced collaterals in retinal vein occlusion]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2001; 37:298-301. [PMID: 11864443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To evaluate the feasibility and safety of establishing chorioretinal venous anastomosis in rabbit eyes with a model of branch retinal vein occlusion METHODS By using laser photocoagulation, a chorioretinal venous anastomosis was created in rabbit eyes in which a branch retinal vein occlusion had previously been established photochemically. A similar attempt to create an anastomosis was made in the control eyes in which no branch vein occlusion was present. RESULTS In the 21 eyes with the model of branch retinal vein occlusion, a chorioretinal venous anastomosis formed in 4 eyes within 3 to 5 weeks. In the control eyes, an anastomosis in one eye presented by 5 weeks, during follow-up of 2 to 5 months. The hemorrhage in choroid, retina and vitreous associated with laser photocoagulation were absorbed within 3 weeks, and no other severe complications were found. CONCLUSIONS Chorioretinal venous anastomosis can be created by using laser photocoagulation. This technique is relatively safe. However, to improve the rate of successfully creating an anastomosis, more research work needs to be performed.
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340
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Shen Z, Tan Y, Wu J, Jiang S. [The difference of intracellular cytokines produced by different lymphocyte subsets of cord blood and adult peripheral blood]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2001; 22:288-91. [PMID: 11877085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To explore the difference of intracellular cytokines between cord blood and adult peripheral blood and elucidate its significance for GVHD. METHOD Different lymphocyte subsets were categorized in cord and adult peripheral blood by monoclonal antibodies with 3 color fluorescence using flow cytometry. The IL-2, TNF-alpha and IFN-gamma produced by various lymphocyte subsets were compared between the two groups. RESULT (1) In cord blood, dominant T cells were CD(4)(+)CD(45RA)(+), while the major T cells were both CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+) in adult peripheral blood. (2) The quantities of IL-2, TNF-alpha and IFN-gamma produced by cord blood lymphocytes were lower than that of adult peripheral blood lymphocytes. Moreover, the majority of cells that produced cytokines in the cord blood were CD(4)(+)CD(45RA)(+), but in adult peripheral blood were mainly CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+). CONCLUSION As compared with adult peripheral blood, the cord blood not only possessed different proportion of lymphocyte subsets, but also significant low level of cytokines. The differences of various lymphocyte subset proportions and lower level of cytokines in cord blood probably related to the lower incidence of GVHD in cord blood stem cell transplantation.
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341
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Li Y, Wang R, Wang X, Shen Z. [Effect of rice canopy structural changes on bidirectional reflectance]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2001; 12:401-4. [PMID: 11758423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The study of vegetation bidirectional reflectance is useful for remote sensing data interpretation. Vegetation canopies information such as leaf area index, mean leaf inclination, mean plant height, and coverage, can be inverted from vegetation bidirectional reflectance. This paper discussed the dynamics of vegetation canopies reflectance with vegetation canopy structures by measuring rice canopy structure and bidirectional reflectance at 26, 35, 41, 49, 62, 67 and 86 days after transplanting. It is concluded that the sensitivity of vegetation canopies to directional reflectance variations varied with canopy structures, and hence, through bidirectional reflectance, more information about canopy structure can be know.
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342
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Shen Z, Wang W, Jia J, Ye J, Feng X, Peng A. Degradation of dye solution by an activated carbon fiber electrode electrolysis system. JOURNAL OF HAZARDOUS MATERIALS 2001; 84:107-116. [PMID: 11376888 DOI: 10.1016/s0304-3894(01)00201-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Degradation of 29 dyes by means of an activated carbon fiber (ACF) electrode electrolysis system was performed successfully. Almost all dye solutions tested were decolorized effectively in this ACF electrolysis process. Internal relationships between treatment mechanisms and chemical composition of the dye have been discussed in this paper. Generally, it is shown that higher solubility leads to greater degradation in the process. Dyes with many -SO3-, COO-, -SO2NH2, -OH, hydrophilic groups, and azo linkages are susceptible to reduction. However, dyes with many -C=O, -NH-and aromatic groups, and hydrophobic groups, tend to be adsorbed. For dyes with -SO3-, COOH and -OH groups, if their molecules linearly spread in solution and have a significant tendency to form colloids by hydrogenous bonding, they also tend to be adsorbed and flocculated. Typical dynamic electrolysis of dye Acid Red B, Vat Blue BO and Disperse Red E-4B shows how the two major mechanisms, degradation and adsorption, act differently during treatment. Reduction occurs evenly during treatment. During the dominant adsorption process, after certain amount of iron is generated, colloid precipitation occurs and TOC and color are rapidly removed.
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Wang H, Shen Z, Yao Z, Luo Y, Zhang Y, Zhang C. [Surgical treatment and reconstruction for the patients with advanced-stage tonsillar cancer]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:261-2. [PMID: 12541776 DOI: pmid/12541776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To investigate the operative approach and reconstruction for the patients with advanced-stage tonsillar cancer. METHOD 7 cases with advanced-stage tonsillar cancer were operated from Dec. 1994 to May 1999. Among them, 5 cases were operated through combined neck-mandible-oral cavity approach (CNMOCA) and with immediate reconstruction. Forearm free skin (FFS) flaps were applied in 3 cases. Pectoralis major myocutaneous (PMM) flaps were applied in 2 cases. 2 other cases were operated separately through approach of oral cavity or lateral pharynx. 6 cases were operated with radical neck dissection. RESULT 5 cases who were operated through CNMOCA or with reconstruction were followed up from 1 year to 5 years and 3 months. They had not recurrence of tumor and complication. All had function recovery of speech. Swallowing or appearance is satisfactory in the 3 cases with FFS flaps. 2 Other cases died as recurrence of tumor in 1 year and 2 years and 10 months post-operation. CONCLUSION CNMOCA is able to provide a good exposure method to remove the extensive tumors completely for the patients with advanced stage tonsillar cancer. It is necessary to reconstruct immediately for the patients.
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Erdmann M, Rubner O, Shen Z, Engel V. Time-resolved photoelectron spectroscopy of Fe(CO)5 multiple fragmentation: theoretical considerations. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00482-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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345
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Zhang Q, Shen Z, Nagai T. Prolonged hypoglycemic effect of insulin-loaded polybutylcyanoacrylate nanoparticles after pulmonary administration to normal rats. Int J Pharm 2001; 218:75-80. [PMID: 11337151 DOI: 10.1016/s0378-5173(01)00614-7] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Insulin-loaded polybutylcyanoacrylate nanoparticles were prepared by emulsion polymerization. The mean diameter of the nanoparticles was 254.7 nm with a polydispersity of 0.064. The associating ratio of insulin to the nanoparticles reached 79.1%. Studies on in vitro release kinetics showed that release profiles can be modeled using a biexponential function and the burst effect was obvious. After various doses of insulin-loaded nanoparticles were intratracheally given to normal rats, significant decrease of glucose level was achieved at each dose group from 5 to 20 IU kg-1. The minimum blood glucose concentration reached 46.9%, 30.4% and 13.6% of the initial level after pulmonary delivery of 5, 10 and 20 IU kg-1 insulin-loaded nanoparticles to normal rats, respectively. The time to reach the minimum blood glucose level (Tmin) was 4, 4 and 8 h for three doses, respectively. The duration of glucose level below 80% of insulin-loaded nanoparticles was much longer than that of insulin solution at every dose. Relative pharmacological bioavailability of insulin-loaded nanoparticles by pulmonary administration was 57.2% over the same formulation by subcutaneous administration.
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Kwek SS, Derry J, Tyner AL, Shen Z, Gudkov AV. Functional analysis and intracellular localization of p53 modified by SUMO-1. Oncogene 2001; 20:2587-99. [PMID: 11420669 DOI: 10.1038/sj.onc.1204362] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2000] [Revised: 02/02/2001] [Accepted: 02/12/2001] [Indexed: 02/02/2023]
Abstract
p53 tumor suppressor is a subject of several post-translational modifications, including phosphorylation, ubiquitination and acetylation, which regulate p53 function. A new covalent modification of p53 at lysine 386 by SUMO-1 was recently identified. To elucidate the function of sumoylated p53, we compared the properties of wild type p53 and sumoylation-deficient p53 mutant, K386R. No differences were found between wild type p53 and K386R mutant of p53 in transactivation or growth suppression assays. Moreover, overexpression of SUMO-1 has no effect on p53-regulated transcription. Biochemical fractionation showed that sumoylated p53 is localized in the nucleus and is tightly bound to chromatin structures. p53 and SUMO-1 co-localized in PML nuclear bodies in 293 cells and the nucleoli in MCF7 and HT1080 cells. However, sumoylation-deficient p53 mutant showed a similar pattern of intranuclear localization, suggesting that SUMO-1 does not target p53 to subnuclear structures. These data indicate that SUMO-1 modification of p53 at lysine 386 may not be essential for p53's cellular localization, transcriptional activation, or growth regulation.
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Shen Z, Zhu W, Huang C, Zeng Y, Han D. [The mechanism of percutaneous transluminal balloon angioplasty as assessed by intracoronary ultrasound]. ZHONGHUA NEI KE ZA ZHI 2001; 40:303-5. [PMID: 11798590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To elucidate the mechanism of coronary balloon angioplasty intracoronary ultrasound imaging. METHOD Intracoronary ultrasound imaging was performed in 68 coronary arteries of 52 patients. Ultrasound images obtained at the treatment site before and after balloon angioplasty were analyzed quantitatively for cross-sectional lumen area, area enclosed by internal elastic lamina (IELA) and plaque area. Qualitative analysis included assessment of presence of dissection, plaque composition and plaque topography. RESULTS The internal elastic lamina area was significantly enlarged after balloon angioplasty [(6.67 +/- 1.45) mm(2) vs (8.14 +/- 1.13) mm(2), P < 0.05]. The difference between IELA before and after balloon angioplasty DeltaIELA was different among different plaques (fatty plaque 1.84 mm(2), fibrous plaque 1.52 mm(2), calcified plaque 0.40 mm(2), mixed plaque 1.23 mm(2)). 85% of the lesions had dissection in some degree after PTCA. Severe dissections occurred mostly in calcified lesions. CONCLUSION The improvement in lumen dimensions after coronary balloon angioplasty is a result of both vessel stretch, as demonstrated by a larger internal elastic lamina area at the treated site, and dissection. Calcified lesions will have less vessel stretch and severer dissection after balloon angioplasty.
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Zhao W, Wang H, Wang X, Wu F, Guo W, Qu B, Shen Z, Wang Z. Effects of All-Trans-Retinoic Acid and Arsenic Trioxide on the Hemostatic Disturbance Associated with Acute Promyelocytic Leukemia. Thromb Res 2001; 102:197-204. [PMID: 11369412 DOI: 10.1016/s0049-3848(01)00233-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To study the in vivo effect of all-trans-retinoic acid (ATRA) and arsenic trioxide (As(2)O(3)) on the expression of tissue factor (TF) and the other hemostatic disturbance, a series of parameters were measured either in bone marrow blasts or plasma from acute promyelocytic leukemia (APL) patients. The plasma parameters were measured by ELISA or chromogenic studies. The TF transcription was assessed using reverse transcription-polymerase chain reaction (RT-PCR) technique. The results indicated that the blast cell procoagulant activity (PCA), TF antigen of APL cell lysate, as well as the transcription of APL TF mRNA elevated at diagnosis, were reduced after ATRA or As(2)O(3) therapy. The plasma level of P-selectin, TF, thrombin-antithrombin complex (TAT), soluble fibrinmonomer complex, thrombomodulin (TM), tissue factor pathway inhibitor (TFPI), plasmin-antiplasmin complex, tissue plasminogen activator (t-PA) activity, urokinase plasminogen activator (u-PA) and its receptor (u-PAR), and D-dimer (D-D) significantly increased. Fibrinogen (Fg), antigen level of protein C (PC), plasminogen (PLG) activity, alpha(2)-plasminogen inhibitor activity (alpha(2)-PI), and plasminogen activator inhibitor (PAI) activity were decreased at diagnosis. The protein C activity (PC:A) and protein S (PS) remained unchanged. All the parameters were restored to normal ranges after complete remission (CR) except elevation of TF and TAT in both groups, as well as PC:A, PS, and t-PA in the ATRA group. In conclusion, there existed activation of platelets and consumption of anticoagulants as well as activation of coagulation and fibrinolytic system before treatment. Both ATRA and As(2)O(3) therapy downregulated the expression of TF mRNA, decreased the PCA and TF level in APL cells, significantly inhibited coagulation activation, corrected secondary hyperfibrinolysis and the other hemostatic abnormalities, and thus greatly improved the bleeding symptom in early stage of the treatment.
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Shen Z, Boustani I, Erdmann M, Engel V. Characterization of nuclear wave packets prepared by chirped femtosecond pulses using time-resolved photoelectron spectroscopy. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00362-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Li L, Shen Z, Wang H, Fu S, Cheng G. Investigation of infection risk and the value of urine endotoxin during extracorporeal shock wave lithotripsy. Chin Med J (Engl) 2001; 114:510-3. [PMID: 11780415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To clarify the infection risks and the value of endotoxin determination in urine during extracorporeal shock wave lithotripsy (ESWL). METHODS According to the distribution and complications of upper urinary calculi, 164 patients were divided into five groups. Group A consisted of 48 patients with 1 to 4 renal calculi, which were or less than 2 cm in diameter. Group B was composed of 24 patients with renal calculus larger than 2 cm in diameter or one to multiple renal calculi. Group C was composed of 22 patients with 1 to 3 renal calculi accompanied by 1 to 2 ureteric calculi. Group D consisted of 51 patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter, respectively. Group E included 19 patients with complicated renal calculus, such as casting and staghorn renal calculus. Urine and blood samples of these patients were obtained before and after ESWL, respectively. Their urine samples were proven sterile prior to treatment. All samples were cultured for bacteria and investigated for endotoxin concentration by the limulus lysate test. RESULTS No significant difference in serum endotoxin was noted before and after ESWL. Blood bacterial cultures were all negative in all patients after ESWL, similar to those before ESWL. Significant increases in urine endotoxin after ESWL compared with that before ESWL in patients of Groups B, C and E were observed, respectively (P < 0.05). There was no significant difference in urine endotoxin after ESWL compared with that before ESWL in patients of Groups A and D. The positive incidences of urine bacterial culture were significantly increased (P < 0.05) in Groups B and C and very significantly increased (P < 0.01) in Group E compared with those in Groups A and D. CONCLUSIONS Urinary infection risk following ESWL was lower in patients with one to several renal calculi, which were less than 2 cm in diameter and did not interfere obviously with the urine flow or in patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter. The risk was higher in those with complicated calculi, such as casting, staghorn renal calculus, renal calculus larger than 2 cm in diameter or renal calculi accompanied by ureteric calculi. For patients with higher infection risk after ESWL, prophylactic antibiotics are necessary even if bacteriuria is not present before ESWL. Endotoxin determination in urine is a reliable, sensitive and simple method for the diagnosis of bacterial infection in patients undergoing ESWL.
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