601
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Qian X, Lin Y, Sun M. [Change of angiotensin system activity and the effects of corticosteroid on it in asthmatic guinea pigs]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2000; 22:577-9. [PMID: 12903409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To investigate the role of angiotensin system(ATs) and effect of corticosteroid on ATs activity at the onset of asthma. METHODS After establishing asthmatic model of guinea pig by intraperitoneal injection with ovalbumin to sensitize and inhalation with the same sensitizer 3 weeks later to induce asthma attack, the levels of angiotensin(AT) I and AT II and the activity of angiotensin converting enzyme(ACE) were measured respectively in extractive fluid of chopped lung tissue, bronchial alveolar lavage fluid (BALF) and plasma (ACE activity in serum) in three groups of experimental guinea pigs including asthmatic group, control group and corticosteroid group. RESULTS In the chopped lung tissue and BALF, the AT I, AT II levels and the ACE activity in the asthmatic group were significantly higher than that in the control group(P < 0.01), however, they did not differ significantly each other in plasma in three groups(P > 0.05). In corticosteroid group, the levels of AT I, AT II and ACE activity were significantly decreased in the BALF compared with that in the asthmatic group(P < 0.01). CONCLUSION The results suggest that the lung tissue may have a local angiotensin system that may be activated and play a role in asthma attack, and the inhibition of ATs activity may be one of the mechanisms in the effects of inhaled corticosteroid on prevention and control of asthma.
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602
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Tang H, Ma Y, Li C, Du R, Le G, Zhuang J, Liu Y, Sun M, Dai C. [Construction of plasmids expressing hepatitis E virus antigen fragments and their combinations]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2000; 22:562-5. [PMID: 12903405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE Several different regions of the HEV antigen were expressed in Escherichia coli and their immunological characteristics were simply evaluated. METHODS Three coding sequences of immunodominant antigenic regions in structural protein of the hepatitis E virus (ORF2.1: 6287-6403nt, ORF2.2: 6743-7126nt, ORF3: full length of ORF3) were amplified by RT-PCR from the fecal supernatants of macaques experimentally infected with HEV. These three fragments were inserted into the pThioHisC expression vector separately or fused in line by (Gly)n short arms. After identified by DNA sequence analysis, these six recombinant plasmids were transformed into Escherichia coli, and immunology characteristics of expressed antigen fragments were evaluated by Western blotting. RESULTS All six genes were successfully expressed in Escherichia coli. Western blotting assay showed that the recombinant proteins specifically reacted with the serum antibody from hepatitis E patient in various degrees. CONCLUSION Artificial antigen based on strung epitopes provides a promising strategy for detection and prevention of HEV infection.
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603
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Sun M, Lee J, Yu L, Geller AI. Modest increases in the titers of helper virus-free herpes simplex virus 1 (HSV-1) vectors by packaging in a cell line with inducible expression of HSV-1 VP16 or by treatment with N,N'-hexamethylene-bis-acetamide. Acta Virol 2000; 44:365-9. [PMID: 11332280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
A recently developed helper virus-free HSV-1 vector system has potential for both gene therapy and physiological studies, but relatively low vector titers have complicated use of this system. In this report, we explored improving the vector titers by isolating a Vero cell line that uses the tetracycline-regulated promoter system to induce HSV-1 VP16 at the beginning of the packaging procedure. We isolated the required cell line and demonstrated that it supports enhanced expression from a HSV-1 immediate early (IE) promoter. However, use of this cell line in helper virus-free vector packaging results in only a modest, approximately 2-fold increase in the vector titers. Additionally, treating the packaging cells with N,N'-hexamethylene-bis-acetamide (HMBA), which is known to induce HSV-1 IE promoters, also supports only modest increases in the vector titers. These results suggest that the lack of VP16 is not the rate limiting factor in the packaging procedure.
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604
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Sun M, Sakakibara H, Ashida H, Danno G, Kanazawa K. Dietary antioxidants fail in protection against oxidative genetic damage in in vitro evaluation. Biosci Biotechnol Biochem 2000; 64:2395-401. [PMID: 11193407 DOI: 10.1271/bbb.64.2395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Carcinogenesis is believed to be induced through the oxidative damage of DNA, and antioxidants are expected to suppress it. So, the polyphenolic antioxidants in daily foods were investigated to see whether they protect against genetic damage by active oxygen. In the evaluation, we used a bioassay and a chemical determination, a Salmonella mutagenicity test for mutation by a N-hydroxyl radical from one of the dietary carcinogens 3-amino-1-methyl-5H-pyrido[4,3-b]indole and the formation of 8-hydroxyl (8-OHdG) from 2'-deoxyguanosine (2'-dG) in a Fenton OH-radical generating system. Thirty-one antioxidants including flavonoids were compared in terms of radical-trapping activity with bacterial DNA and 2'-dG. Antioxidants inhibited the mutation but the IC50 values were in the mM order. Against 8-OHdG formation, only alpha-tocopherol had a suppressive effect with an IC50 of 1.5 microM. Thus, except alpha-tocopherol, the dietary antioxidants did not scavenge the biological radicals faster than bacterial DNA and intact 2'-dG, indicating that they failed to prevent oxidative gene damage and probably carcinogenesis.
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605
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Kharbanda M, Than S, Chitnis V, Sun M, Chavan S, Bakshi S, Pahwa S. Patterns of CD8 T cell clonal dominance in response to change in antiretroviral therapy in HIV-infected children. AIDS 2000; 14:2229-38. [PMID: 11089610 DOI: 10.1097/00002030-200010200-00003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To examine the influence of change in antiretroviral therapy (ART) on patterns of CD8 T cell clonal dominance in HIV-infected children. DESIGN Seventeen HIV-infected children with plasma virus loads between 3.1 and 5.7 log10 were investigated before and after changes in ART. METHODS CDR3 spectratyping was performed in 22 T cell receptor (TCR) Vbeta subfamilies by multiplex polymerase chain reaction (PCR) in purified peripheral blood CD8 T cells in conjunction with CD4 cell counts, plasma HIV-RNA copies and lymphoproliferative assays (LPA). RESULTS CD8 T cell clonal dominance in two or more Vbeta families was present in eight out of 17 children. After a change in therapy, 13 patients (76%) acquired new clones whereas three patients (17.6%) showed a loss in CD8 cell clones. An increase in the numbers of dominant clones correlated with an increase in percentage CD4 cell counts (P < 0.001) and with improved LPA responses to tetanus (P < 0.05) and alloantigens (P < 0.01). CD4 cell increase was associated with an initial mean gain of 3.1+/-2.1 CD8 cell clones, independent of a virological response. A loss of CD8 cell clones or failure to achieve CD4 T cell increase was associated with failure to achieve virological suppression. CONCLUSION Children with chronic HIV infection manifest CD8 T cell clonal dominance, which appears to be dependent upon the adequacy of the CD4 cells. With optimization of therapy, a gain in clonal dominance is the predominant response, except in situations of failure to contain viral replication.
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606
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Sun M, Goldin E, Stahl S, Falardeau JL, Kennedy JC, Acierno JS, Bove C, Kaneski CR, Nagle J, Bromley MC, Colman M, Schiffmann R, Slaugenhaupt SA. Mucolipidosis type IV is caused by mutations in a gene encoding a novel transient receptor potential channel. Hum Mol Genet 2000; 9:2471-8. [PMID: 11030752 DOI: 10.1093/hmg/9.17.2471] [Citation(s) in RCA: 321] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Mucolipidosis type IV (MLIV) is a developmental neurodegenerative disorder characterized by severe neurologic and ophthalmologic abnormalities. The MLIV gene, ML4 (MCOLN1), has recently been localized to chromosome 19p13.2-13.3 by genetic linkage. Here we report the cloning of a novel transient receptor potential cation channel gene and show that this gene is mutated in patients with the disorder. ML4 encodes a protein, which we propose to call mucolipin, which has six predicted transmembrane domains and is a member of the polycystin II subfamily of the Drosophila transient receptor potential gene family. The role of a potential receptor-stimulated cation channel defect in the pathogenesis of mucolipidosis IV is discussed.
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607
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Johnson MS, Figueroa-Colon R, Herd SL, Fields DA, Sun M, Hunter GR, Goran MI. Aerobic fitness, not energy expenditure, influences subsequent increase in adiposity in black and white children. Pediatrics 2000; 106:E50. [PMID: 11015545 DOI: 10.1542/peds.106.4.e50] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Low levels of energy expenditure and aerobic fitness have been hypothesized to be risk factors for obesity. Longitudinal studies to determine whether energy expenditure influences weight gain in whites have provided conflicting results. To date, no studies have examined this relationship in blacks or whether aerobic fitness influences weight gain in white or black children. METHODS One hundred fifteen children, 72 white (55 girls and 17 boys) and 43 black (24 girls and 19 boys) were recruited for this study. Aerobic fitness, resting, total, and activity-related energy expenditure and body composition were measured at baseline. The children returned annually for 3 to 5 repeated measures of body composition. The influence of the initial measures of energy expenditure and fitness on the subsequent rate of increase in adiposity was examined, adjusting for initial body composition, age, ethnicity, gender, and Tanner stage. Because 20 children did not attain maximum oxygen consumption, the sample size for the combined analysis was 95. RESULTS Initial fat mass was the main predictor of increasing adiposity in this cohort of children, with greater initial fat predicting a higher rate of increase of adiposity. There was also a significant negative relationship between aerobic fitness and the rate of increasing adiposity (F(1,82) = 3.92). With every increase of.1 L/minute of fitness, there was a decrease of.081 kg fat per kg of lean mass gained. None of the measures of energy expenditure significantly predicted increasing adiposity in white or black children. CONCLUSIONS Initial fat mass was the dominant factor influencing increasing adiposity; however, aerobic fitness was also a significant independent predictor of increasing adiposity in this cohort of children. Resting, total, or activity-related energy expenditure did not predict increasing adiposity. It seems that aerobic fitness may be more important than absolute energy expenditure in the development of obesity in white or black children. energy expenditure, fitness, longitudinal, obesity.
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608
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Abstract
A soman-hydrolyzing enzyme (somanase) was purified from human liver. The human somanase is capable of hydrolyzing pinacolyl methylphosphonofluoridate (soman), diisopropylphosphorofluoridate (DFP), and ethyl-N-dimethyl phosphoramidocyanidate (Tabun) with P-F or P-CN bonding, but not ethyl (S-2-diisopropylaminoethyl) methylphosphonothiolate (VX) and diethyl-p-nitro-phosphenylphosphate (paraoxon) with P-S or P-O bonding. The somanase has been purified 1570-fold with a specific activity of 41.4 mumol/min/mg protein. Its molecular weight is around 58 kDa determined by SDS-PAGE. The somanase could be stimulated by the divalent cations Mn+2, Mg+2, and Co+2, where CO+2 activation is the highest. The requirement of disulfide bonds for the enzyme activity was demonstrated by the inhibition effect of DTT.
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609
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Sun M, Liu Z, Yu Z. [Characterization of the insecticidal crystal protein genes of Bacillus thuringiensis YBT-1520]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2000; 40:365-71. [PMID: 12548956] [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 insecticidal crystal protein genes of highly toxic Bacillus thuringiensis YBT-1520 were analyzed. Southern hybridization and PCR analysis indicated that this strain bears cry1Aa, cry1Ab, cry1Ac and cry2 genes. The copy number of three cry1A genes is different and cry1Ac gene (here named cry218) is the highest. The restriction location of three genes is different from that in typical strains, such as HD-1 and HD-73 strains. 4190 bp nucleotide sequence of cry218 gene was determined and this gene was named cry1Ac10 in the recently published gene nomenclature.
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610
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Akgül T, Sun M, Sclabassi RJ, Cetin AE. Characterization of sleep spindles using higher order statistics and spectra. IEEE Trans Biomed Eng 2000; 47:997-1009. [PMID: 10943047 DOI: 10.1109/10.855926] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This work characterizes the dynamics of sleep spindles, observed in electroencephalogram (EEG) recorded from humans during sleep, using both time and frequency domain methods which depend on higher order statistics and spectra. The time domain method combines the use of second- and third-order correlations to reveal information on the stationarity of periodic spindle rhythms to detect transitions between multiple activities. The frequency domain method, based on normalized spectrum and bispectrum, describes frequency interactions associated with nonlinearities occurring in the observed EEG.
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611
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Sun M, Sclabassi RJ. The forward EEG solutions can be computed using artificial neural networks. IEEE Trans Biomed Eng 2000; 47:1044-50. [PMID: 10943052 DOI: 10.1109/10.855931] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Study of electroencenphalography (EEG) is the one of the most utilized methods in both basic brain research and clinical diagnosis of neurological disorders. Recent technological advances in computer and electronic systems have allowed the EEG to be recorded from large electrode arrays. Modeling the brain waves using a head volume conductor model provides an effective method to localize functional generators within the brain. However, the forward solutions to this model, which represent theoretical potentials in response to current sources within the volume conductor, are difficult to compute because of time-consuming numerical procedures utilized in either the boundary element method (BEM) or the finite element method (FEM). This paper presents a novel computational approach using an artificial neural network (ANN) to map two vectors of forward solutions. These two vectors correspond to different head models but with respect to the same current source. The input vector to the ANN is based on the spherical head model, which can be computed efficiently but involves large errors. The output vector from the ANN is based on the spheroidal model, which is more precise, but difficult to compute directly using the traditional means. Our experiments indicate that this ANN approach provides a remarkable improvement over the BEM and FEM methods: 1) the mean-square error of computation was only approximately 0.3% compared to the exact solution; 2) the online computation was extremely efficient, requiring only 168 floating point operations per channel to compute the forward solution, and 10.2 K-bytes of storage to represent the entire ANN. Using this approach it is possible to perform real-time EEG modeling accurately on personal computers.
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612
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Liao Z, Qi Z, Sun M, Yang D, Yun J. [The influences of human apolipoprotein E mutants on the learning and memory of cerebral cortex in transgenic mice]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2000; 22:348-51. [PMID: 12903448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To study the influences of the mutants of human apolipoprotein E on the function of cerebral cortex. METHODS The Southern blot hybridization and ELISA techniques were used for identification of integration and expression of human apoE4 and apoE7 genes at the mice chromosome and in the serum of F1 transgenic mice. Then the active avoidance response test was performed to determine the alteration of learning and short term and long term memory of the transgenic mice. The serum total cholesterol (TC) and triglyceride (TG) were determined simultaneously with enzymatic procedure. RESULTS (1) In F1 transgenic mice the human apoE genes integrated at the chromosome and expressed in their serum stably. (2) In apoE4 mice the learning and short term memorizing abilities were decreased, and in apoE7 mice the short term memorizing abilities were decreased as well. In addition, the TC and TG increased statistically. CONCLUSIONS The overexpression of human apoE4 and apoE7 genes in transgenic mice could damage the function of cerebral cortex. It denoted that the mutations of apoE might correlate the pathogenesis of Alzheimer's disease.
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613
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Sun M, Wang Y, Fan G. [Effects of activating blood circulation to remove blood stasis on barrier action of gastric wall in chronic atrophic gastritis]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 2000; 20:554. [PMID: 11789216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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614
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Sun M, Sakakibara H, Ashida H, Danno G, Kanazawa K. Cytochrome P4501A1-inhibitory action of antimutagenic anthraquinones in medicinal plants and the structure-activity relationship. Biosci Biotechnol Biochem 2000; 64:1373-8. [PMID: 10945253 DOI: 10.1271/bbb.64.1373] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have earlier found that flavones and flavonols in vegetables specifically inhibited one of the carcinogenesis-related enzymes, cytochrome P450 (CYP) 1A1, and subsequently suppressed the mutagenicity of food-derived carcinogens. In this study, we explored other candidates for the enzyme inhibitor in Chinese medicinal plants. Some of them were antimutagenic toward 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2). For example, Rheum officinale contained large amounts of anthraquinones as the active compounds, 3.4 mg of emodin, 2.1 mg of chrysophanol and 1.8 mg of rhein in 10 g of dry matter. Anthraquinones showed similar IC50 values for antimutagenicity against Trp-P-2 to those for inhibition of the N-hydroxylation activity of CYP1A1 toward Trp-P-2, indicating that the antimutagenicity was attributable to CYP inhibition. The structure-activity relationships were then examined with 14 commercial chemicals, and it was found that the interaction with an enzyme required three rings and an oxygen group in the side ring. This characteristic is similar to that of flavones and flavonols.
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615
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Sun M, Zhou HY, Deng HZ. [Study of the risk factors of blood pressure in children]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 25:238-40. [PMID: 12212152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The blood pressure of 495 normal children aged nine to fourteen years were measured. The body height, weight, blood lipid profile, fasting blood glucosum(FBS) were also measured. The children's family history of hypertension and their dietary status and physical exercise status were investigated. The results showed that the older the child, the higher the blood pressure. On single factor analysis, systolic blood pressure (SBP) was positively correlated with age, family history of hypertension, intake of whole lipid milk, body height, weight, BMI, blood TC, LDL-C and FBS, whereas it was negatively correlated with the time of physical exercises and blood HDL-C/TC. Diastolic blood pressure(DBP) was positively correlated with age, body height, weight, IBM, FBS, blood TC and LDL-C, whereas it was negatively correlated with blood HDL-C/TC. Multifactor regression analysis showed that weight, age, blood TC and FBS had significant effects on SBP, while weight, age, blood TC and LDL-C had significant effect on DBP. Therefore, avoiding obesity, improving dietary status, taking more physical exercises and suitably lowering blood lipid and FBS should be carried out in children.
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616
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Wu L, Sun M, Yu Z. [A new resolution vector with cry1Ac10 gene based on Bacillus thuringiensis transposon Tn4430]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2000; 40:264-9. [PMID: 12548990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
A new resolution vector with cry1Ac10 gene based on TnpI-mediated site-specific recombination system of Bacillus thuringiensis(Bt) transposon Tn4430 was developed. The gene cry1Ac10, encoding a protoxin against plutella xylostella larvae, and the gene ori1030, from a plasmid of wide type Bacillus thuringiensis, were inserted into two copy sets of RES sites, named pBMB801. When pBMB801 was introduced into crystal negative Bt host BMB171, antibiotic resistance genes and other non-Bt DNA can be selectively eliminated. This recombinant plasmid was found very stable without antibiotic selection. The resulting strain only contained Bt DNA and is free of antibiotic resistance genes. This strategy should facilitate regulatory approval for its development as a commercial biopesticide.
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617
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Huang J, Sun M. Fluorescein PAGE analysis of microsatellite-primed PCR: a fast and efficient approach for genomic fingerprinting. Biotechniques 2000; 28:1068, 1070, 1072. [PMID: 10868269 DOI: 10.2144/00286bm03] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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618
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Yuan ZQ, Sun M, Feldman RI, Wang G, Ma X, Jiang C, Coppola D, Nicosia SV, Cheng JQ. Frequent activation of AKT2 and induction of apoptosis by inhibition of phosphoinositide-3-OH kinase/Akt pathway in human ovarian cancer. Oncogene 2000; 19:2324-30. [PMID: 10822383 DOI: 10.1038/sj.onc.1203598] [Citation(s) in RCA: 284] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We previously demonstrated that AKT2, a member of protein kinase B family, is activated by a number of growth factors via Ras and PI 3-kinase signaling pathways. Here, we report the frequent activation of AKT2 in human primary ovarian cancer and induction of apoptosis by inhibition of phosphoinositide-3-OH kinase (PI 3-kinase)/Akt pathway. In vitro AKT2 kinase assay analyses in 91 ovarian cancer specimens revealed elevated levels of AKT2 activity (>3-fold) in 33 cases (36.3%). The majority of tumors displaying activated AKT2 were high grade and stages III and IV. Immunostaining and Western blot analyses using a phospho-ser-473 Akt antibody that detects the activated form of AKT2 (AKT2 phosphorylated at serine-474) confirmed the frequent activation of AKT2 in ovarian cancer specimens. Phosphorylated AKT2 in tumor specimens localized to the cell membrane and cytoplasm but not the nucleus. To address the mechanism of AKT2 activation, we measured in vitro PI 3-kinase activity in 43 ovarian cancer specimens, including the 33 cases displaying elevated AKT2 activation. High levels of PI 3-kinase activity were observed in 20 cases, 15 of which also exhibited AKT2 activation. The remaining five cases displayed elevated AKT1 activation. Among the cases with elevated AKT2, but not PI 3-kinase activity (18 cases), three showed down-regulation of PTEN protein expression. Inhibition of PI 3-kinase/AKT2 by wortmannin or LY294002 induces apoptosis in ovarian cancer cells exhibiting activation of the PI 3-kinase/AKT2 pathway. These findings demonstrate for the first time that activation of AKT2 is a common occurrence in human ovarian cancer and that PI 3-kinase/Akt pathway may be an important target for ovarian cancer intervention.
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619
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Mao Y, Sun M, Desai SD, Liu LF. SUMO-1 conjugation to topoisomerase I: A possible repair response to topoisomerase-mediated DNA damage. Proc Natl Acad Sci U S A 2000; 97:4046-51. [PMID: 10759568 PMCID: PMC18143 DOI: 10.1073/pnas.080536597] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ubiquitin/26S proteasome-dependent degradation of topoisomerase I (TOP1) has been suggested to be a unique repair response to TOP1-mediated DNA damage. In the current study, we show that treatment of mammalian cells or yeast cells expressing human DNA TOP1 with camptothecin (CPT) induces covalent modification of the TOP1 by SUMO-1/Smt3p, a ubiquitin-like protein. This conclusion is based on the following observations: (i) Mammalian DNA TOP1 conjugates induced by CPT were cross-reactive with SUMO-1/Smt3p-specific antibodies both in yeast expressing human DNA TOP1 as well as mammalian cells. (ii) The formation of TOP1 conjugates was shown to be dependent on UBC9, the E2 enzyme for SUMO-1/Smt3p. (iii) TOP1 physically interacts with UBC9. (iv) Ubc9 mutant yeast cells expressing human DNA TOP1 was hypersensitive to CPT, suggesting that UBC9/SUMO-1 may be involved in the repair of TOP1-mediated DNA damage.
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621
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Gibb W, Sun M, Gyomorey S, Lye SJ, Challis JR. Localization of prostaglandin synthase type-1 (PGHS-1) mRNA and prostaglandin synthase type-2 (PGHS-2) mRNA in ovine myometrium and endometrium throughout gestation. J Endocrinol 2000; 165:51-8. [PMID: 10750035 DOI: 10.1677/joe.0.1650051] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Increased prostaglandin production by tissues in the sheep uterus and placenta are thought to be important for the onset of parturition. In the sheep placenta, this is most likely due to increased expression of prostaglandin synthase type-2 (PGHS-2) rather than prostaglandin synthase type-1 (PGHS-1). However, there is no information concerning expression of PGHS isoenzymes in maternal uterine tissues during pregnancy. Therefore, the purpose of the present study was to examine the expression of PGHS-1 and PGHS-2 in the sheep myometrium and endometrium during late gestation using in situ hybridization and immunohistochemistry. Using (35)S-labelled oligonucleotide probes, which give specific hybridization signals in other tissues, we localized PGHS-2 mRNA to endometrial epithelium, and apparently to other cells in both endometrium and myometrium. This artefactual signal was still present with 100-fold excess unlabelled oligonucleotide probe and with sense probes, but was resolved with the use of (33)P-oligonucleotides. Using (33)P-labelled oligonucleotide probes we could not detect either PGHS-1 or PGHS-2 mRNA in myometrium, and found expression only of PGHS-2 mRNA in endometrium. PGHS-2 mRNA localized to the endometrial epithelium and was undetectable in glandular epithelium. The level of PGHS-2 expression rose significantly between days 80 and 85 of pregnancy and term, and this corresponded to the appearance of immunoreactive PGHS-2 protein, measured by immunohistochemistry, in the endometrial epithelium. Therefore we conclude that (33)P-labelled probes are preferred for detection of mRNAs encoding PGHS-2 in ovine uterine tissues. Expression of PGHS-2 mRNA is greater than that of PGHS-1, increases during gestation, and predominates in the endometrial epithelium, consistent with the site of PGHS-2 protein localization.
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622
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Zhao C, Maring C, Sun M, Stewart K, Stoll V, Xu Y, Gu Y, Krueger A, Herrin T, Sham H, Laver W, Madigan D, Kennedy A, Kati W, Montgomery D, Saldivar A, Kempf D, Kohlbrenner W. 58 Design, synthesis and activity of substituted pyrrolidine influenza neuraminidase inhibitors. Antiviral Res 2000. [DOI: 10.1016/s0166-3542(00)90389-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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623
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Pan R, Sun M, Zhou H, Jia Z. [Effects of lotensin and nitrendipine on plasma fibrinogen and platelet aggregation in hypertensive patients]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:87-9. [PMID: 10681808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Plasma fibrinogen and platelet aggregation were measured by turbidimetric immunoassay, turbidimetry in 47 hypertensive patients and 20 normotensive control subjects. Among the 47 hypertensives, 24 cases were received lotensin and 23 nitrendipine. The plasma fibrinogen was increased and platelet aggregation enhanced in hypertensive patients before treatment. Platelet aggregation decreased after 8 weeks of treatment with lotensin or nitrendipine respectively. Lotensin decreased plasma fibrinogen whereas nitrendipine did not. It was concluded that both lotensin and nitrendipine decreased platelet aggregation; lotensin decreased plasma fibrinogen but nitrendipine did not.
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624
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Xu H, Sun M, Zhou H. [Changes of plasma endothelin-1 in patients with congestive heart failure and the influence of metoprolol]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:467-9. [PMID: 10682563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
To investigate the alterations of plasma endothelin-1(ET-1) in patients with congestive heart failure(CHF) and the effects of metoprolol on it, plasma ET-1 and norepinephrine(NE) were measured in 43 patients using radioimmunoassay and high-performance liquid chromatography methods. Twenty-four patients were treated with metoprolol plus the routine therapy while the others were received the routine therapy only. The findings were that levels of plasma ET-1 and NE increased before the treatment, and decreased after the treatment with metoprolol for 1 month. There was no alteration of plasma ET-1 or NE in the control group.
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625
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Ma Q, Zhou H, Sun M, Wu S. [Relationship between sex hormone levels and blood lipids/immunity in perimenopausal women]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:461-4. [PMID: 10682561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
To investigate the relationship between sex hormone levels and blood lipids/immunity and to evaluate the therapeutical effects of nylestriol, 96 women without coronary heart disease(CHD) were studied during their perimenopausal period. The estimation of serum biochemical components included serum 17 beta-estradiol(E2), testosterone(T), total cholesterol(TC), triglyceride (TC), high density lipoprotein cholesterol(HDL-C), low density protein cholesterol(LDL-C), apolipoprotein A-I(ApoAI), apolipoprotein B(ApoB), lipoprotein (a)[Lp(a)], immunoglobulin G(IgG), and IgG antibody against cardiolipin(ACAIgG). Thirty-six postmenopausal volunteers were divided into two groups and randomized to treat with either 2 mg nylestriol or placebo. In postmenopausal women, serum levels of E2, E2/T, HDL, and ApoAI decreased, while those of T, TC, TG, LDL, ApoB, Lp(a), IgG, and ACAIgG increased. Serum level of E2 was positively correlated to HDL-C and negatively correlated to TC, ApoB, LDL, IgG, and ACAIgG. Serum level of T was positively correlated to LDL, IgG, and ACAIgG and negatively correlated to HDL. In the nylestriol group, as compared with the results before treatment, serum levels of TG, TC, LDL, IgG, and ACAIgG decreased and that of HDL-C increased after treatment. We conclude that estradiol is a protective factor of CHD, whereas testerone is a dangerous factor. After menopause, the imbalance of the estradiol/testosterone ratio increases the incidence of CHD. Nylestriol is an effective substitute for estradiol to prevent CHD in post menopausal women.
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