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Gao L, Pan J, Wu S, Xie C, Zhong M, Chen X, Jin Y, Wu G, Cai J, Xu G. PO-077: Cetuximab Plus Radiotherapy for Chinese Patients with Locally Advanced Head and Neck Cancer. Radiother Oncol 2013. [DOI: 10.1016/s0167-8140(15)34696-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Meng F, Sun G, Zhong M, Yu Y, Brewer MA. Anticancer efficacy of cisplatin and trichostatin A or 5-aza-2'-deoxycytidine on ovarian cancer. Br J Cancer 2013; 108:579-86. [PMID: 23370212 PMCID: PMC3593556 DOI: 10.1038/bjc.2013.10] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND To evaluate the anticancer efficacy of the combination of epigenetic modifiers and cisplatin in human ovarian cancer. METHODS The effect of trichostatin A (TSA) and 5-aza-2'-deoxycytidine alone or in combination with low-dose cisplatin was evaluated on human ovarian cancer cell lines in vitro. We measured drug interaction by MTS assay, migration by transwell assay, expression of epithelial to mesenchymal transition (EMT) markers (Twist, Snail, Slug, E-cadherin, and N-cadherin), pluripotency markers (Oct4, Sox2, and Nanog), and epigenetic markers (DNMT3A, LSD1 and H3K4me2, H3K4me3, H3K9me2, and H3K9me3) by western blot, and the impact on and characteristics of spheroid growth when exposed to these drugs. Mouse xenografts were used to evaluate the anticancer effect of sequential drug treatment. RESULTS Combination treatment had greater efficacy than single drugs and significantly suppressed cell viability, migration, and spheroid formation and growth. Sequential treatment of cisplatin (1 mg kg(-1)) followed by TSA (0.3 mg kg(-1)) significantly suppressed tumorigenicity of HEY xenografts through inhibition of EMT and decreased pluripotency of ovarian cancer cells. CONCLUSION Epigenetic modifiers potentiate the anticancer efficacy of low-dose cisplatin in ovarian cancer through regulation of EMT and pluripotency, and may provide a promising treatment for ovarian cancer patients.
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Sun G, Zhang X, Xu X, Yang J, Zhong M, Yuan J. A new triterpene From Uncaria macrophylla and its antitumor activity. Molecules 2012; 17:1883-9. [PMID: 22334066 PMCID: PMC6268741 DOI: 10.3390/molecules17021883] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 02/03/2012] [Accepted: 02/07/2012] [Indexed: 11/21/2022] Open
Abstract
On our ongoing investigation, a new oleanolic triterpene, 3β,6β,19α-trihydroxy-12-oleanen-28-oic acid (1) was obtained from the chloroform-soluble portion of the 90% alcohol-water extract of the stem bark of Uncaria macrophylla. Its structure was elucidated by extensive spectroscopic methods, including 1D and 2D (1H-1H COSY, HSQC and HMBC) NMR and HR-ESI-MS. The cytotoxicities of the compound was evaluated against two cancer cell lines of MCF-7 and HepG2 by the MTT method, and the compound exhibited weak activities with the IC50 values of 78.2 µg/mL and 73.9 µg/mL.
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Sun G, Zhang X, Xu X, Yang J, Zhong M, Yuan J. A new triterpene from the plant of uncaria macrophylla. Molecules 2012; 17:504-10. [PMID: 22222909 PMCID: PMC6268033 DOI: 10.3390/molecules17010504] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Revised: 12/29/2011] [Accepted: 12/30/2011] [Indexed: 11/16/2022] Open
Abstract
Our ongoing investigations on the stem bark of Uncaria macrophylla afforded a new ursolic triterpene, 3β,6β,19α-trihydroxy-urs-12-en-28-oic acid-24-carboxylic acid methyl ester (1), named uncariursanic acid, and three known ursolic triterpenes including 3β,6β,19α-trihydroxy-23-oxo-urs-12-en-28-oic acid (2), 3β,6β,19α-trihydroxy-urs-12-en-28-oic acid (3) and ursolic acid (4). Their structures were elucidated by extensive spectral methods, including 1D and 2D NMR and HR-ESI-MS. The cytotoxicities of the four compounds were evaluated against two cancer cell lines (MCF-7 and HepG2) by the MTT method, and only compound 4 exhibited potent activity.
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Fan R, Zhong M, Wang S, Zhang Y, Andrew A, Karagas M, Chen H, Amos CI, Xiong M, Moore JH. Entropy-based information gain approaches to detect and to characterize gene-gene and gene-environment interactions/correlations of complex diseases. Genet Epidemiol 2011; 35:706-21. [PMID: 22009792 PMCID: PMC3384547 DOI: 10.1002/gepi.20621] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
For complex diseases, the relationship between genotypes, environment factors, and phenotype is usually complex and nonlinear. Our understanding of the genetic architecture of diseases has considerably increased over the last years. However, both conceptually and methodologically, detecting gene-gene and gene-environment interactions remains a challenge, despite the existence of a number of efficient methods. One method that offers great promises but has not yet been widely applied to genomic data is the entropy-based approach of information theory. In this article, we first develop entropy-based test statistics to identify two-way and higher order gene-gene and gene-environment interactions. We then apply these methods to a bladder cancer data set and thereby test their power and identify strengths and weaknesses. For two-way interactions, we propose an information gain (IG) approach based on mutual information. For three-ways and higher order interactions, an interaction IG approach is used. In both cases, we develop one-dimensional test statistics to analyze sparse data. Compared to the naive chi-square test, the test statistics we develop have similar or higher power and is robust. Applying it to the bladder cancer data set allowed to investigate the complex interactions between DNA repair gene single nucleotide polymorphisms, smoking status, and bladder cancer susceptibility. Although not yet widely applied, entropy-based approaches appear as a useful tool for detecting gene-gene and gene-environment interactions. The test statistics we develop add to a growing body methodologies that will gradually shed light on the complex architecture of common diseases.
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Meng F, Sun G, Zhong M, Yu Y, Brewer M. Epigenetic regulation and tumorigenicity of ovarian cancer cells. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e15546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Heestand GM, Pipas JM, Valone F, McMullen AD, Gadea P, Williams D, Zhong M, Neff T, Fisher GA, Koong A. A phase I trial of the monoclonal antibody FG-3019 to connective tissue growth factor (CTGF) in locally advanced or metastatic pancreatic cancer. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.4_suppl.269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
269 Background: CTGF is highly expressed in pancreatic tumors and is thought to mediate local desmoplasia. FG-3019 is a fully human monoclonal antibody against CTGF. Studies using FG-3019 in murine xenograft models have shown reduced tumor growth and metastasis. Methods: This open-label, dose escalation study assessed the safety and pharmacokinetics of FG-3019 (3, 10, 15, and 25 mg/kg q14D). FG-3019 was initiated on D1 to assess single-agent toxicity. Standard gemcitabine and erlotinib were added on D15. Chemotherapy-naive patients with locally advanced or metastatic adenocarcinoma were eligible. Seventeen subjects (median age 66 yrs) were enrolled: n=4, 3, and 10 at 3, 10, and 15 mg/kg respectively. Enrollment is ongoing in the 25 mg/kg cohort. Seven subjects were female; four were stage 3, and 13 were stage 4. Results: No safety signals were detected with single-agent FG-3019. After beginning chemotherapy, four subjects experienced seven SAEs, which were deemed unrelated to FG-3019 including three deaths: sepsis, suicide, and disease progression. Nine subjects experienced grade 3 AEs, all of which were expected in patients with pancreatic cancer. There were no grade 4 hematologic abnormalities. AEs related to gemcitabine (hematologic, abnormal LFTs) and erlotinib (rash) occurred at a rate and severity consistent with the prescribing information (preliminary data). Steady-state Cmax (median 428, range 236-455 μg/mL), and T1/2 (median 6.6, range 6.3-6.7 days) at the 10 mg/kg dose level were comparable to PK data from subjects in non-oncological trials who received FG-3019 at the same dose level. One subject had a partial response by RECIST criteria for 9.7+ months. Another subject had a minor response for 7.7 months. Three of five subjects with PET scans at baseline and D15 experienced stable to reduced PET activity before starting chemotherapy. The median TTP across all cohorts was 3.7 months (95% CI 1.9-6.2), and the median OS was 9.4 months (95% CI 1.9-10.6). Conclusions: FG-3019 is well tolerated and dose escalation continues. Reduced PET activity after treatment with single-agent FG-3019 may indicate a biological effect of the agent. [Table: see text]
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Zhong M, Carney DH, Jo H, Boyan BD, Schwartz Z. Inorganic phosphate induces mammalian growth plate chondrocyte apoptosis in a mitochondrial pathway involving nitric oxide and JNK MAP kinase. Calcif Tissue Int 2011; 88:96-108. [PMID: 21104071 DOI: 10.1007/s00223-010-9433-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Accepted: 09/02/2010] [Indexed: 10/18/2022]
Abstract
Chondrocytes in the hypertrophic zone of the growth plate undergo apoptosis during endochondral bone development via mechanisms that involve inorganic phosphate (Pi) and nitric oxide (NO). Recent evidence suggests that Pi-dependent NO production plays a role in apoptosis of cells in the resting zone as well. This study examined the mechanism by which Pi induces NO production and the signaling pathways by which NO mediates its effects on apoptosis in these cells. Pi decreased the number of viable cells based on MTT activity; the number of TUNEL-positive cells and the level of DNA fragmentation were increased, indicating an increase in apoptosis. Blocking NO production using the NO synthase (NOS) inhibitor L: -NAME or cells from eNOS(-/-) mice blocked Pi-induced chondrocyte apoptosis, indicating that NO production is necessary. NO donors NOC-18 and SNOG both induced chondrocyte apoptosis. SNOG also upregulated p53 expression, the Bax/Bcl-2 expression ratio, and cytochrome c release from mitochondria, as well as caspase-3 activity, indicating that NO induces apoptosis via a mitochondrial pathway. Inhibition of JNK, but not of p38 or ERK1/2, MAP kinase was able to block NO-induced apoptosis, indicating that JNK is necessary in this pathway. Pi elevates NO production via eNOS in resting zone chondrocytes, which leads to a mitochondrial apoptosis pathway dependent on JNK.
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Zhong M, Carney DH, Boyan BD, Schwartz Z. 17β-Estradiol regulates rat growth plate chondrocyte apoptosis through a mitochondrial pathway not involving nitric oxide or MAPKs. Endocrinology 2011; 152:82-92. [PMID: 21068162 DOI: 10.1210/en.2010-0509] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estrogens cause growth plate closure in both males and females, by decreasing proliferation and inducing apoptosis of postproliferative growth plate chondrocytes. In vitro studies using 17β-estradiol (E(2)) conjugated to bovine serum albumin (E(2)-BSA) show that rat costochondral growth plate resting zone chondrocytes also respond to E(2). Moreover, they are regulated by E(2)-BSA via a protein kinase C and ERK MAPK signaling pathway that is functional only in female cells. To better understand how E(2) regulates apoptosis of growth plate chondrocytes, rat resting zone chondrocytes cells were treated with E(2) or E(2)-BSA. E(2) caused apoptosis in male and female resting zone and growth zone chondrocytes in a dose-dependent manner, based on elevated DNA fragmentation, terminal deoxynucleotidyl transferase dUTP nick end labeling staining and caspase-3 activation. E(2) also up-regulated p53 and Bax protein (Bcl-2-associated X protein) levels and induced release of cytochrome C from the mitochondria, indicating a mitochondrial apoptotic pathway. The apoptotic effect of E(2) did not involve elevated nitric oxide production or MAPKs. It was reduced by ICI 182780, which is an estrogen receptor (ER) antagonist and blocked by antibodies to Erα36, a membrane-associated ER. E(2)-BSA reduced cell viability and increased caspase-3 activity; ICI 182780 had no effect, but anti-ERα36 antibodies blocked the effect. The results indicate that estrogen is able to directly affect the cell population kinetics of growth plate chondrocytes by regulating apoptosis, as well as proliferation and differentiation in both resting zone and growth zone cells. They also have provided further information about the physiological functions of estrogen on longitudinal bone growth.
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Guo YD, Cai JF, Li X, Xiong F, Su RN, Chen FL, Liu QL, Wang XH, Chang YF, Zhong M, Wang X, Wen JF. Identification of the forensically important sarcophagid flies Boerttcherisca peregrina, Parasarcophaga albiceps and Parasarcophaga dux (Diptera: Sarcophagidae) based on COII gene in China. Trop Biomed 2010; 27:451-460. [PMID: 21399586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Accurate species identication is a crucial step in forensic entomology, as the insect collected on a corpse can provide useful information for estimation of postmortem interval (PMI). The utility of the forensically important Sarcophagidae (Diptera) for crime scene investigation has been severely restricted, as morphological identification is difficult, especially the identification of females and larvae. In this study, a method for using mitochondrial DNA (mtDNA) sequence data and phylogenetic analysis was performed to distinguish the three Chinese sarcophagid species: Boerttcherisca peregrina (Robineau-Desvoidy, 1830) Parasarcophaga albiceps (Meigen, 1826) and Parasarcophaga dux (Thompson, 1869) (Diptera: Sarcophagidae). DNA was extracted and analyzed by a 189 bp fragment of cytochrome coxidase subunit II (COII) gene. The monophyletic branches of the phylogenetic tree reveal that this marker is suitable for discrimination between these species, providing high support for separation on congeneric species. Therefore, the molecular method applied to the sarcophagid species identification is feasible.
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Hurst-Kennedy J, Zhong M, Gupta V, Boyan BD, Schwartz Z. 24R,25-Dihydroxyvitamin D3, lysophosphatidic acid, and p53: a signaling axis in the inhibition of phosphate-induced chondrocyte apoptosis. J Steroid Biochem Mol Biol 2010; 122:264-71. [PMID: 20594980 DOI: 10.1016/j.jsbmb.2010.05.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 05/23/2010] [Accepted: 05/27/2010] [Indexed: 11/20/2022]
Abstract
Maintenance of the pool of chondrocytes in the resting zone of the growth plate in the presence of the physiological apoptogen inorganic phosphate (Pi) is crucial for skeletal development. Costochondral resting zone chondrocytes are regulated by the vitamin D metabolite 24R,25-dihydroxyvitamin D3 [24R,25(OH)(2)D(3)], with increased production of sulfated glycosaminoglycan-rich extracellular matrix, and reduced matrix metalloproteinase activity. The effects of 24R,25(OH)(2)D(3) are mediated by activation of phospholipase D (PLD), resulting in increased production of lysophosphatidic acid (LPA) and LPA-mediated proliferation, maturation, inhibition of Pi-induced apoptosis, and reduction of p53. However, the exact mechanism by which 24R,25(OH)(2)D(3) and LPA exert their effects is not fully understood. It was found that both 24R,25(OH)(2)D(3) and LPA attenuate Pi-induced caspase-3 activity. The actions of 24R,25(OH)(2)D(3) and LPA were dependent upon G(αi), LPA receptor(s) 1 and/or 3, PLD, phospholipase C (PLC), and intracellular calcium, phosphoinositide 3-kinase (PI(3)K) signaling, and nuclear export. 24R,25(OH)(2)D(3) decreased both p53 abundance and p53-medaited transcription and inhibited Pi-induced cytochrome c translocation. Moreover, LPA induced increased mdm2 phosphorylation, a negative regulator of p53. Taken together, these data show that 24R,25(OH)(2)D(3) inhibits Pi-induced apoptosis through Ca(2+), PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation, resulting in decreased cytochrome c translocation and caspase-3 activity.
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Wei W, Liu SY, Zeng FF, Yao SP, Zhang HT, Wan G, Zhong M, Yang Z, Wang BY. Type 2 diabetes and impaired glucose tolerance in North-China-based rural community adults. Public Health 2010; 124:593-601. [DOI: 10.1016/j.puhe.2010.05.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 05/08/2010] [Accepted: 05/26/2010] [Indexed: 10/19/2022]
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Li X, Cai JF, Guo YD, Wu KL, Wang JF, Liu QL, Wang XH, Chang YF, Yang L, Lan LM, Zhong M, Wang X, Song C, Liu Y, Li JB, Dai ZH. The availability of 16S rRNA for the identification of forensically important flies (Diptera: Muscidae) in China. Trop Biomed 2010; 27:155-166. [PMID: 20962711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Many species of Muscidae are cosmopolitan synanthropic insects. It is frequently found on dead bodies after death, so an accurate identification of each species is necessary for the correct estimation of the postmortem interval (PMI). Identification species of Muscidae is traditionally performed through their morphological features. However, the morphological similarity of Muscidae in the level of species usually poses a challenge for forensic entomologists. Therefore a molecular method used 16S rRNA sequence on mitochondrial DNA was established for species identification. In this study, a 289 base pair region of mitochondrial DNA (mtDNA) coding for 16S rRNA was investigated for identification of the following forensically important species of Muscidae. The specimens were from four genera, including 18 Musca domestica (Linnaeus, 1758), 2 Ophyra spinigera (Stein, 1910), 2 Ophyra chalcogaster (Wiedemann, 1824), 1 Morellia hortorum (Fallén, 1817), and 1 Fannia canicularis (Linnaeus, 1761). 16S rDNA region allowed the identification of these species of Muscidae, indicating the possibility of separation congeneric species with molecular method.
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Hu Z, Jin X, Kang Y, Liu C, Zhou Y, Wu X, Liu J, Zhong M, Luo C, Deng L, Deng Y, Xie X, Zhang Z, Zhou Y, Liao X. Angiotensin-converting enzyme insertion/deletion polymorphism associated with acute respiratory distress syndrome among caucasians. J Int Med Res 2010; 38:415-22. [PMID: 20515555 DOI: 10.1177/147323001003800204] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Studies investigating the association between angiotensin-converting enzyme (ACE) insertion/deletion polymorphisms and the risk of acute respiratory distress syndrome (ARDS) report conflicting results. The objective of the present study was to summarize quantitatively the evidence for such a relationship. Two investigators independently searched the MEDLINE (January 1966 - October 2009) and EMBASE (January 1980 - October 2009) databases. This meta-analysis included six case-control studies, which included 514 ARDS cases and 2619 controls. The combined results based on all studies showed that patients with ARDS had a significantly higher frequency of the ACE deletion/deletion (DD) genotype (odds ratio [OR] 1.56; 95% confidence interval [CI] 1.22, 2.00) than controls. When stratifying for race, no significant differences in genotype distribution were found except that Caucasian patients with ARDS had a significantly higher frequency of the DD genotype (OR 1.65; 95% CI 1.27, 2.13) than controls. This meta-analysis suggests that ACE insertion/deletion polymorphisms may be associated with ARDS among Caucasians.
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Zhong M, Zhang X, Wang Y, Zhang C, Chen G, Hu P, Li M, Zhu B, Zhang W, Zhang Y. An interesting case of rifampicin-dependent/-enhanced multidrug-resistant tuberculosis. Int J Tuberc Lung Dis 2010; 14:40-44. [PMID: 20003693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023] Open
Abstract
We report a case of rifampicin (RMP) dependent/enhanced multidrug-resistant (MDR-TB) from a patient who had been treated with the World Health Organization optional thrice-weekly treatment and document the clinical and bacteriological features. RMP-enhanced tubercle bacilli that grew poorly without RMP but grew better in its presence were isolated from the patient with treatment failure. The bacteria grown without RMP consisted of mixed morphologies of short rod-shaped acid-fast bacteria and poorly stained coccoid bacteria, but stained normally as acid-fast rods when grown in the presence of RMP. The isolated RMP-enhanced bacteria harbored the common S531L mutation and a novel mutation F584S in the rpoB gene. Treatment containing RMP or replacement of RMP with more powerful rifapentine paradoxically aggravated the disease, but its removal led to successful cure of the patient. This study highlights the potential dangers of continued treatment of MDR-TB with rifamycins that can occur due to delayed or absent drug susceptibility results and calls for timely detection of RMP-dependent/-enhanced bacteria in treatment failure patients by including RMP in culture media and removal of RMP from treatment regimen upon detection.
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Wu G, Xie YL, Chen H, Zhong M, Liu RH, Shi BC, Li QJ, Wang XF, Wu T, Yan YJ, Ying JJ, Chen XH. Superconductivity at 56 K in samarium-doped SrFeAsF. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:142203. [PMID: 21825317 DOI: 10.1088/0953-8984/21/14/142203] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We synthesized the samples Sr(1-x)Sm(x)FFeAs with a ZrCuSiAs-type structure. These samples were characterized by resistivity and susceptibility. It is found that substitution of rare earth metal for alkaline earth metal in this system suppresses the anomaly in resistivity and induces superconductivity. Superconductivity at 56 K in nominal composition Sr(0.5)Sm(0.5)FFeAs is realized, indicating that the superconducting transition temperatures in the iron arsenide fluorides can reach as high as that in oxypnictides with the same structure.
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Bi XP, Tan HW, Xing SS, Zhong M, Zhang Y, Zhang W. Felodipine downregulates serum interleukin-18 levels in rats with fructose-induced metabolic syndrome. J Endocrinol Invest 2009; 32:303-7. [PMID: 19636195 DOI: 10.1007/bf03345716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Human studies suggest that calcium-channel blockers have cardiovascular protection besides reducing blood pressure, and interleukin-18 (IL-18) levels which are elevated in obese population are associated with metabolic syndrome (MetS). The purpose of this research was to study the change of serum IL-18 levels and the effect of felodipine on it in high-fructose diet-fed rats. METHODS In this research, 30 Wistar male rats were randomized into 3 groups. A control group (no.=12) was fed with normal feeds, and high-fructose diet was given to a fructose group and a flodioine group (no.=9 in each group). All animals were fed for a period of 32 weeks, during which body weight and systolic blood pressure (BP) were measured once every 4 weeks. Felodipine (5 mg/kg/d) was then administered by gavage daily for 6 weeks to the felodipine group. Before and after treatment with felodipine, fasting plasma lipid, blood glucose, plasma insulin, and serum IL-18 were detected. RESULTS Body weight, systolic BP, triglycerides, fasting insulin, and the R-value of homeostasis model (HOMA-R) were significantly increased in high-fructose rats (p<0.01). Serum IL-18 levels were elevated and had significant positive correlation with HOMA-R in rats with fructose-induced MetS (p<0.01). We also found that felodipine may decrease HOMA-R and serum IL-18 levels besides reducing blood pressure (p<0.05, p<0.01). CONCLUSION IL-18 plays an important role in the development of MetS, while felodipine exerts an anti-inflammatory effect on rats with fructose-induced MetS by downregulating serum IL-18 levels.
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Bento JL, Palmer ND, Zhong M, Roh B, Lewis JP, Wing MR, Pandya H, Freedman BI, Langefeld CD, Rich SS, Bowden DW, Mychaleckyj JC. Heterogeneity in gene loci associated with type 2 diabetes on human chromosome 20q13.1. Genomics 2008; 92:226-34. [PMID: 18602983 DOI: 10.1016/j.ygeno.2008.06.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 04/11/2008] [Accepted: 06/04/2008] [Indexed: 11/26/2022]
Abstract
Human chromosome 20q12-q13.1 has been linked to type 2 diabetes mellitus (T2DM) in multiple studies. We screened a 5.795-Mb region for diabetes-related susceptibility genes in a Caucasian cohort of 310 controls and 300 cases with T2DM and end-stage renal disease (ESRD), testing 390 SNPs for association with T2DM-ESRD. The most significant SNPs were found in the perigenic regions: HNF4A (hepatocyte nuclear factor 4alpha), SLC12A5 (potassium-chloride cotransporter member 5), CDH22 (cadherin-like 22), ELMO2 (engulfment and cell motility 2), SLC13A3 (sodium-dependent dicarboxylate transporter member 3), and PREX1 (phosphatidylinositol 3,4,5-triphosphate-dependent RAC exchanger 1). Haplotype analysis found six haplotype blocks globally associated with disease (p<0.05). We replicated the PREX1 SNP association in an independent case-control T2DM population and inferred replication of CDH22, ELMO2, SLC13A3, SLC12A5, and PREX1 using in silico perigenic analysis of two T2DM Genome-Wide Association Study data sets. We found substantial heterogeneity between study results.
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Zhao B, Zhong M, Jin K. Neurogenesis and neurodegenerative diseases in human. Panminerva Med 2008; 50:55-64. [PMID: 18427388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Acute and chronic neurodegenerative diseases are the most common neurological disorders in human and affect millions of individuals worldwide. While the specific clinical presentation varies among such diseases, their common feature is neural cell death. Yet, despite major advances in the understanding of neural cell death, effective treatment for these diseases remains one of the foremost challenges for medicine today. The transplantation of embryonic cells into the diseased brain in human has emerged out a mere theory and is possible as a practical application. This advancement, however, has raised important ethical, technical and immunological concerns. Studies have documented that neurogenesis occurs in the adult brain and that endogenous neural stem/progenitor cells (NSCs) respond to neurodegenerative diseases, suggesting that it might be possible for dead or injured neural cells to be replaced by endogenous NSCs. In this regard it is especially interesting to know the biological behaviors of endogenous NSCs in response to neurodegenerative diseases. Understanding the mechanisms underlying these changes could lead to the development of new strategies for treating neurological diseases using endogenous NSC pool.
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Zhong M, Wike L, Ryaby J, Carney D, Boyan B, Schwartz Z. Thrombin peptide TP508 prevents nitric oxide mediated apoptosis in chondrocytes in the endochondral developmental pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1783:12-22. [DOI: 10.1016/j.bbamcr.2007.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 10/12/2007] [Accepted: 10/16/2007] [Indexed: 11/25/2022]
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McMillan J, Fatehi-Sedeh S, Sylvia VL, Bingham V, Zhong M, Boyan BD, Schwartz Z. Sex-specific regulation of growth plate chondrocytes by estrogen is via multiple MAP kinase signaling pathways. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:381-92. [PMID: 16713447 DOI: 10.1016/j.bbamcr.2006.02.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2005] [Revised: 02/07/2006] [Accepted: 02/27/2006] [Indexed: 10/24/2022]
Abstract
Both male and female rat growth plate cartilage cells possess estrogen receptors (ERs), but 17beta-estradiol (E(2)) activates protein kinase C (PKC) and PKC-dependent biological responses to E(2) only in cells from female animals. PKC signaling can elicit genomic responses via mitogen activated protein kinase (MAPK) and E(2) has been shown to activate ERK MAPK in many cells, suggesting that MAPK may play a role in growth plate chondrocytes as well. We tested if E(2) increases MAPK activity and if so, whether the response is limited to female cells, if it is PKC-dependent, and if the mechanism involves traditional ER pathways. We also determined the contribution of MAPK to the biological response of growth plate chondrocytes and assessed the relative contributions of ERK, p38 and JNK MAPKs. Female rat costochondral cartilage cells were treated with E(2) and MAPK-specific activity determined in cell layer lysates. The mechanism of MAPK activation was determined by treating the cells with E(2) conjugated to bovine serum albumin (E(2)-BSA) to assess if membrane receptors were involved; stereospecificity was determined using 17alpha-estradiol; PKC and phospholipase C (PLC) dependence was determined using specific inhibitors; and the ER agonist diethylstilbestrol, the ER antagonist ICI 182780, and tamoxifen were used to assess the role of traditional ER pathways. E(2) regulation of ERK1/2 MAPK was assessed and the relative roles of ERK1/2, p38 and JNK MAPKs determined using specific inhibitors. E(2) caused a rapid dose-dependent activation of MAPK that was greatest in cells treated for 9 min with 10(-9) M hormone; activity remained elevated for 3 h. E(2)'s effect on MAPK was stereospecific and comparable to that of E(2)-BSA. It was insensitive to DES and ICI 182780, dependent on PKC and PLC, blocked by tamoxifen and it did not require gene transcription or translation. E(2) had no effect on ERK1 or ERK2 mRNA or protein but it caused a rapid phosphorylation of ERK1/2 at 9 min. Inhibition of ERK1/2 and p38 MAPK reduced the stimulatory effects of E(2) on alkaline phosphatase activity and [(35)S]-sulfate incorporation. These results suggest that E(2) regulates MAPK through a sex-specific membrane-mediated mechanism that does not involve cytosolic ERs in a traditional sense and that ERK1/2 and p38 mediate the downstream biological effects of the hormone.
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Xu XM, Zhou YQ, Luo GX, Liao C, Zhou M, Chen PY, Lu JP, Jia SQ, Xiao GF, Shen X, Li J, Chen HP, Xia YY, Wen YX, Mo QH, Li WD, Li YY, Zhuo LW, Wang ZQ, Chen YJ, Qin CH, Zhong M. The prevalence and spectrum of alpha and beta thalassaemia in Guangdong Province: implications for the future health burden and population screening. J Clin Pathol 2004; 57:517-22. [PMID: 15113860 PMCID: PMC1770296 DOI: 10.1136/jcp.2003.014456] [Citation(s) in RCA: 270] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/28/2003] [Indexed: 11/04/2022]
Abstract
AIM Thalassaemia is a good candidate disease for control by preventive genetic programmes in developing countries. Accurate population frequency data are needed for planning the control of thalassaemia in the high risk Guangdong Province of southern China. METHODS In total, 13397 consecutive samples from five geographical areas of Guangdong Province were analysed for both haematological and molecular parameters. RESULTS There was a high prevalence of carriers of alpha thalassaemia (8.53%), beta thalassaemia (2.54%), and both alpha and beta thalassaemia (0.26%). Overall, 11.07% of the population in this area were heterozygous carriers of alpha and beta thalassaemia. The mutation spectrum of alpha and beta thalassaemia and its constitution were fully described in this area. This study reports the true prevalence of silent alpha thalassaemia in the southern China population for the first time. In addition, two novel mutations that give rise to alpha thalassaemia, one deletion resulting in beta thalassaemia, and a rare deletion (--(THAI) allele) previously unreported in mainland China were detected. The frequency of the most common mutation, the Southeast Asian type of deletion (--(SEA), accounting for 48.54% of all alpha thalassaemias) was similar to the total of two alpha(+) thalassaemia deletions (-alpha(3.7) and -alpha(4.2), accounting for 47.49% of alpha thalassaemia). CONCLUSION Both alpha and beta thalassaemia are widely distributed in Guangdong Province of China. The knowledge gained in this study will enable the projected number of pregnancies at risk to be estimated and a screening strategy for control of thalassaemia to be designed in this area.
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Jian Z, Chen F, Xie Q, Liu W, Zhong M. [Expression of WT1 gene mRNA in leukemia]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2002; 24:341-2. [PMID: 12080641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
UNLABELLED WT1 gene expression was determined in acute leukemic patients by RT-PCR. RESULTS 19 patients were found to have positive results among 28 patients, the positive rate is 67.9%, and in 16 ANLL patients, 11 cases got positive results, in 12 ALL patients, 8 cases got positive results. It suggested that WT1 was highly expressed in acute leukemia. It is a new and significant detective marker for monitoring the effect of chemotherapy, predicting the prognosis and in the research of minimal residual disease (MRD).
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Adams RP, Zhong M, Fei Y. Preservation of DNA in plant specimens: inactivation and re-activation of Dnases in field specimens. Mol Ecol 2002. [DOI: 10.1046/j.1365-294x.1999.84600.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ding S, Zhong M, Jeinsch T, Tang B. LMI-BASED INTEGRATION OF ROBUST H∞-CONTROL AND RFD FOR LTI SYSTEMS. ACTA ACUST UNITED AC 2002. [DOI: 10.3182/20020721-6-es-1901.00758] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kim MK, Banevicius MA, Zhong M, Shi X, Hu M, Nightingale CH, Nicolau DP. Clearance of quinupristin-dalfopristin (Synercid) and their main metabolites during continuous veno-venous hemofiltration (CVVH) with or without dialysis. Int J Artif Organs 2002; 25:33-9. [PMID: 11853069 DOI: 10.1177/039139880202500106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Quinupristin-dalfopristin (Q/D) is often utilized in critically ill patients, some of whom require CVVH. This study was undertaken to determine the clearance of O/D and their main active metabolites (RPR 100391, RP 69012, RP 12536) via CVVH in the swine model. METHODS Q/D 7.5 mg/kg was intravenously administered over 0.5 h to 12 swine after induction of acute renal failure by ligation of the renal arteries. At 0.5 h post injection, the CVVH procedure was initiated and continued for 8 hours at the following pump rates: (1)100 mL/min, (2)180 rnL/min, and (3)100 mL/min with dialysis (flow rate: 1 L/h). Blood and ultrafiltrate samples were collected at 1 h intervals and assessed by a validated HPLC method. RESULTS Plasma analysis suggests rapid metabolism to the main active metabolites which are appreciably cleared as demonstrated by high clearance and sieving coefficient estimates. Mean clearance estimates for RP 69012, RP 100391, and RP 12536 are 729, 777, and 578 mL/h in the 100 mL/min CVVH group, 772, 785, 685 mL/min in the 180 mL/min CVVH group, and 753, 791, 616 mL/min in the 100 mL/min CVVH group with 1 L/h dialysis, respectively. CONCLUSION These data reveal that Q/D is rapidly metabolized and the metabolites are cleared to a large extent via CVVH. Due to the considerable contribution of the metabolites to overall in vivo activities, additional studies are required to fully quantify their removal before final dosage modifications for patients undergoing CVVH can be recommended.
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Joseph T, Wooden R, Bryant A, Zhong M, Lu Z, Foster DA. Transformation of cells overexpressing a tyrosine kinase by phospholipase D1 and D2. Biochem Biophys Res Commun 2001; 289:1019-24. [PMID: 11741292 DOI: 10.1006/bbrc.2001.6118] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipase D (PLD) activity is elevated in response to most mitogenic signals. Two mammalian PLD genes (PLD1 and PLD2) have been cloned and their gene products have been characterized. PLD1 is a downstream target of the Ras/RalA GTPase cascade implicated in mitogenic and oncogenic signaling. Consistent with a role in mitogenic signaling, elevated expression of PLD1 transforms cells overexpressing the epidermal growth factor (EGF) receptor (EGFR). However, PLD2 colocalizes with the EGFR in caveolin-enriched light membrane microdomains. We therefore investigated whether PLD2 could also contribute to the transformation of cells overexpressing a tyrosine kinase. We report here that elevated expression of PLD2 transforms rat fibroblasts overexpressing either the EGFR or c-Src. Since overexpression of a tyrosine kinase is a common genetic alteration in several human cancers, these data suggest that elevation of either PLD1 or PLD2 may contribute to the progression to a malignant phenotype in cells with elevated tyrosine kinase activity.
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Xu XR, Huang J, Xu ZG, Qian BZ, Zhu ZD, Yan Q, Cai T, Zhang X, Xiao HS, Qu J, Liu F, Huang QH, Cheng ZH, Li NG, Du JJ, Hu W, Shen KT, Lu G, Fu G, Zhong M, Xu SH, Gu WY, Huang W, Zhao XT, Hu GX, Gu JR, Chen Z, Han ZG. Insight into hepatocellular carcinogenesis at transcriptome level by comparing gene expression profiles of hepatocellular carcinoma with those of corresponding noncancerous liver. Proc Natl Acad Sci U S A 2001; 98:15089-94. [PMID: 11752456 PMCID: PMC64988 DOI: 10.1073/pnas.241522398] [Citation(s) in RCA: 272] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Human hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. In this work, we report on a comprehensive characterization of gene expression profiles of hepatitis B virus-positive HCC through the generation of a large set of 5'-read expressed sequence tag (EST) clusters (11,065 in total) from HCC and noncancerous liver samples, which then were applied to a cDNA microarray system containing 12,393 genes/ESTs and to comparison with a public database. The commercial cDNA microarray, which contains 1,176 known genes related to oncogenesis, was used also for profiling gene expression. Integrated data from the above approaches identified 2,253 genes/ESTs as candidates with differential expression. A number of genes related to oncogenesis and hepatic function/differentiation were selected for further semiquantitative reverse transcriptase-PCR analysis in 29 paired HCC/noncancerous liver samples. Many genes involved in cell cycle regulation such as cyclins, cyclin-dependent kinases, and cell cycle negative regulators were deregulated in most patients with HCC. Aberrant expression of the Wnt-beta-catenin pathway and enzymes for DNA replication also could contribute to the pathogenesis of HCC. The alteration of transcription levels was noted in a large number of genes implicated in metabolism, whereas a profile change of others might represent a status of dedifferentiation of the malignant hepatocytes, both considered as potential markers of diagnostic value. Notably, the altered transcriptome profiles in HCC could be correlated to a number of chromosome regions with amplification or loss of heterozygosity, providing one of the underlying causes of the transcription anomaly of HCC.
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Collman JP, Zhong M, Costanzo S, Zhang C. New imidazole-based tripodal ligands as Cu(B) site mimics of cytochrome C oxidase. J Org Chem 2001; 66:8252-6. [PMID: 11722236 DOI: 10.1021/jo010737m] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Collman JP, Zhong M, Zhang C, Costanzo S. Catalytic activities of Cu(II) complexes with nitrogen-chelating bidentate ligands in the coupling of imidazoles with arylboronic acids. J Org Chem 2001; 66:7892-7. [PMID: 11701055 DOI: 10.1021/jo010615u] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zhong M, Zheng W, Wu J. [Microsurgical treatment of 86 cases of intracranial aneurysms]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2001; 39:664-6. [PMID: 11769596] [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 summarize the microsurgical experience in the treatment of intracranial aneurysms. METHOD The clinical materials, surgical modes and prognosis of 86 cases of clipped intracranial aneurysms were retrospectively reviewed. RESULTS Of the 86 cases, 69 recovered, 10 were moderately disabled, 2 severely disabled, and 5 died. CONCLUSIONS To avoid rerupture, aneurysms should be treated as soon as possible when the diagnosis was established. Proper management of rupture of aneurysms during operation is the key of success. Multiple aneurysms are better to be clipped in one stage. "de novo" aneurysms could be detected early by long-term angiography.
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Zhong M, Zhang Y, Zhang W. [Molecular mechanism underlying calcium handling in diastolic heart failure]. ZHONGHUA YI XUE ZA ZHI 2001; 81:669-72. [PMID: 11798946] [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 molecular mechanism underlying calcium handling in diastolic heart failure (DHF) from mRNA level and protein expression, including L-type calcium channel, sarcoplasmic reticulum (SR) Ca(2+)-ATPase, phospholamban, ryanodine receptor, calsequestrin. METHODS DHF was produced in rabbits by abdominal aortic coarctation. The mRNA amounts of these calcium-handling genes were measured by RT-PCR, while the protein levels of SR Ca(2+)-ATPase and phospholamban were analyzed by Western blot analysis. RESULTS The content of calcium was significantly increased in myocardium of rabbits with DHF than in the myocardium of sham-operated rabbits. The SR Ca(2+)-ATPase activity of DHF rabbits was significantly reduced compared with that in sham-operated rabbits (21.1 micromol.mg(-1).h(-1) +/- 5.7 micromol.mg(-1).h(-1) vs 10.5 micromol.mg(-1).h(-1) +/- 2.8 micromol.mg(-1).h(-1), P < 0.01). RT-PCR analyses showed that the steady-state level of mRNA encoding the L-type calcium channel and SR Ca2+-ATPase was decreased significantly in rabbits with DHF compared with that in the sham-operated rabbits (micromol.mg(-1).h(-1)): 0.75 +/- 0.11 vs 1.20 +/- 0.33; 0.76 +/- 0.12 vs 1.24 +/- 0.38, P < 0.05). The SR Ca(2+)-ATPase mRNA level correlated negatively well with left ventricular relaxation time constant and left ventricular end-diastolic pressure (r = -0.81, -0.64, respectively, P < 0.05 approximately 0.01); the mRNA level of L-type calcium channel correlated negatively with left ventricular end-diastolic pressure (r = -0.74, P < 0.05). The mRNA level of ryanodine receptor correlated negatively with the left ventricular relaxation time constant too (r = -0.71, P < 0.05). Protein level of SR Ca(2+)-ATPase was significantly lower in rabbits with DHF than in the sham-operated rabbits (0.76 +/- 0.6 vs 1.02 +/- 0.09, P < 0.05), whereas the protein level of phospholamban was unchanged. CONCLUSION The L-type calcium channel and SR Ca(2+)-ATPase were down regulated in DHF. These changes may be a contributory factor for DHF.
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Zhong M, Wen S, Zhou F. [Transfusion transmitted virus infection in mother-to-infant transmission]. ZHONGHUA FU CHAN KE ZA ZHI 2001; 36:328-9. [PMID: 11783126] [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 investigate the perinatal infection of transfusion transmitted virus (TTV) in the mother-to-infant transmission and molecular evidence. METHODS TTV was examined in serum from 104 mothers and umbilical blood of their infants by a semi-nested polymerase chain reaction technique. TTV nucleotide sequences isolated from two sets of mother/infant pairs were analyzed. RESULTS The TTV detection rate was 13.46% (15/104), and it was 4.81% (5/104) in the umbilical blood of their newborns. Homology analysis was done by sequencing between positions 1,915 and 2,185 of the published TTV genome, Analysis of TTV sequences from the 2 pairs of mother and infant both infected confirmed a genetic link between the virus of the infected mother and their infected infants. CONCLUSIONS There is a possibility of vertical maternal-fetal transmission of TTV.
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Zhao Y, Zhong M, Liu Z, Xu X. [Rapid detection of the common alpha-thalassemia-2 determinants by PCR assay]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2001; 18:216-8. [PMID: 11402454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE Most frequent molecular lesions of alpha-thalassemia-2 determinants are deletions of one alpha-globin gene. Satisfactory PCR methodologies for detecting the deletions are required for molecular diagnosis and genetic screening since there was no internal control in most published PCR-based strategies. The purpose of this study is to develop a reliable PCR protocol specific for the two common alpha-thalassemia-2 determinants with internal control. METHODS The multiple repeat elements and the high GC-content of the alpha-globin locus impose severe limitations on designing suitable primers and optimizing stable conditions for PCR. In this study, two multiplex PCR systems were successfully set up. One was designed to detect the rightward deletion (-alpha(3.7)/) with two pairs of primers including one newly optimized pair for amplification of the internal standard to indicate the success of failure of PCR amplification. The other, to the leftward deletion(-alpha(4.2)/) with three primers, which were designed according to the newly sequenced data of the -alpha(4.2) and HbQ-alpha(4.2) deletions in this lab(Genbank Accession No. AF221717). In the PCR system, one is used as a common upstream primer and the other two are used as specific downstream primers for typing the normal allele and the deletion one, respectively. RESULTS Easily interpretable, unambiguous amplifications were observed by using the multiplex PCR systems for the detection of the two common alpha-thalassemia-2 determinants. The three or four primers were run in the same tube under the same condition and both of these two systems could be used at the same thermal cycle parameters. For typing the rightward deletion, a mutant-specific amplification of 1.7 kb and a 1140 bp amplified band as a normal and system control were produced. For typing the leftward deletion, two PCR-amplified bands, a 956 bp fragment specific for a -alpha(4.2) gene and a 1140 bp one for a normal allele were found. CONCLUSION Two sets of PCR systems with internal controls for detecting the most common two alpha-thalassemia-2 determinants have been established and may be suitable for molecular diagnosis and population screening.
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Zhong M, Tai A, Yamamoto I. IgE production is involved in butyrate-enhanced NK cell activity in vivo. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 2001; 16:76-81. [PMID: 12901494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
It has been demonstrated that patients with asthma have a large number of NK cells and show a stronger NK activity. These results indicate that NK cell activity may be related to total IgE level in serum in healthy subjects. Previously, we have found that sodium butyrate (NaBu) markedly enhanced the IL-4-induced IgE production in the LPS-stimulated murine splenocytes in vitro, and inductive rat IgE production in vivo, and enhanced the NK cell activity ex vivo. We hypothesized that the IgE production might be involved in butyrate-enhanced NK cell activity in vivo. Mice were intraperitoneally treated/immunized with NaBu or/and Ascaris suum extract (ASC), and the spleen NK cell activity was evaluated. Furthermore, the effect of serum (NAS) on IL-2- or IFN-gamma-induced spleen NK cell activity was determined. The spleen NK cell activity and IL-2- or IFN-gamma-induced spleen NK cell activity of mice treated/immunized with NaBu or/and ASC were stronger than those of untreated/unimmunized mice. Although IL-4 blocked IL-2 (100 U/ml)- or IFN-gamma (100 U/ml)-induced increase in NK cell activity, these NK cell activities in mice treated/immunized with NaBu/ASC were not inhibited. IgE production showed a tendency to rise in NaBu-treated mice serum, and a synergistic effect was observed with treatment of NaBu and ASC. Moreover, the NAS significantly increased IL-2(25 U/ml)-or IFN-gamma(25 U/ml)-induced NK cell activity, and its effect was inhibited by anti-mouse IgE mAb. These data show that IgE plays an important role in NAS-enhanced IL-2/IFN-gamma-induced NK cell activity, and IL-4 does not inhibit IgE and IL-2/IFN-gamma-induced NK cell activity in mice.
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Zhong M, Jost-Brinkmann PG, Zellmann M, Zellmann S, Radlanski RJ. Clinical evaluation of a new technique for interdental enamel reduction. J Orofac Orthop 2001; 61:432-9. [PMID: 11126018 DOI: 10.1007/pl00001911] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In orthodontics, reduction of tooth-size by grinding interproximal surfaces (stripping) of teeth is a common procedure. In order to achieve perfectly smooth surfaces, clinicians have carefully tested various methods and progressively improved this therapeutic procedure. In this in-vivo study we used scanning electron microscopy (SEM) to evaluate the morphologic effect of a 3-step technique using an oscillating perforated diamond-coated disc for enamel reduction and 2 Sof-Lex XT discs for polishing. This technique was applied in 32 patients with an average age of 15.5 years. A total of 296 interproximal surfaces was treated and replicas were produced for scanning electron microscopy evaluation. The scanning electron microscopy investigations demonstrated that more than 90% of the reproximated surfaces were very well or well polished, resulting in polished enamel surfaces smoother than untreated enamel. This technique proved to be clinically expedient as it finished each interproximal surface within about 2.2 minutes. At the same time, it was demonstrated to be safe and comfortable for the patient, eliminating the need for lip or cheek protectors and making injuries unlikely.
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Zhao P, Zhong M, Song X, Lu Y, Wang D, Gu Z, Chen L. [Expression of heparanase gene and the metastatic activity of lung cancer]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2001; 4:88-90. [PMID: 21044460 DOI: 10.3779/j.issn.1009-3419.2001.02.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND To investigate the relationship between the expression of heparanase gene and the metastatic activity of lung cancer. METHODS Using the primers of heparanase gene, the expression of heparanase gene was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in two giant cell lung cancer cell lines with different metastatic activity and 56 primary tumor tissues of lung cancer and normal lung tissues. RESULTS Both cell lines and 80% (20/25) of primary tumor tissues of lung cancer with lymph node metastasis showed positive expression of heparanase gene, whereas 6.5% (2/31) primary tumor tissues of lung cancer without lymph node metastasis was positive and the normal lung tissues were all negative. The positive rate for expression of heparanase gene was significantly higher in the tumor tissues with lymph node metastasis than that without lymph node metastasis (P<0.001), higher in squamous cell carcinoma (47.2%, 17/36) than that in adenocarcinoma (20%, 4/20)(P<0.05), and remarkably higher in the poorly differentiated tumors (65%, 13/20) than that in the well-mediate differentiated tumors (22.2%, 8/36)(P<0.01). CONCLUSIONS The preliminary results suggest that the expression of heparanase gene may be one of the reliable markers for the metastastic activity gained by the lung cancer cells and could be used clinically in predicting the prognosis of patients.
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Zhong M, Lu Z, Abbas T, Hornia A, Chatakondu K, Barile N, Kaplan P, Foster DA. Novel tumor-promoting property of tamoxifen. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 2001; 12:187-92. [PMID: 11331247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The tumor-promoting phorbol ester TPA (12-O-tetradecanoylphorbol-13-acetate) cooperates with c-Src overexpression to transform rat fibroblasts. TPA transforms c-Src-overexpressing cells by depleting the delta isoform of protein kinase C (PKCdelta). Tamoxifen, which has both estrogen-mimetic and estrogen-antagonist properties, has been widely used to improve the prognosis of breast cancer patients. However, with extended use, there is an increased risk for endometrial and other cancers that can be observed within 10 years of treatment. We report here that tamoxifen, similar to TPA, cooperates with c-Src overexpression to transform 3Y1 rat fibroblasts. Tamoxifen induced both DNA synthesis and anchorage-independent cell proliferation in c-Src-overexpressing, but not in parental, 3Y1 rat fibroblasts. Tamoxifen also induced an association between c-Src and PKCdelta that resulted in the tyrosine phosphorylation and down-regulation of PKCdelta. These phenotypes were not induced by estrogen, indicating that the effect of tamoxifen was in addition to any estrogen-mimetic effects. Thus, in addition to the hyperplasia-inducing capability of an estrogen-mimetic, tamoxifen has an additional tumor-promoting capability similar to that of TPA. The dual tumor-promoting capability of both estrogen- and TPA-mimetic properties for tamoxifen may contribute to the increased incidence of endometrial cancers observed in the relatively short exposure period of <10 years.
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Bian K, Harari Y, Zhong M, Lai M, Castro G, Weisbrodt N, Murad F. Down-regulation of inducible nitric-oxide synthase (NOS-2) during parasite-induced gut inflammation: a path to identify a selective NOS-2 inhibitor. Mol Pharmacol 2001; 59:939-47. [PMID: 11259640 DOI: 10.1124/mol.59.4.939] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nitric oxide (NO) possesses potent anti-inflammatory properties; however, an over-production of NO will promote inflammation and induce cell and tissue dysfunction. Thus, the ability to precisely regulate NO production could prove beneficial in controlling damage. In this study, advantage was taken of the well characterized inflammatory response caused by an intestinal parasite, Trichinella spiralis, to study the relationship between intestinal inflammation and the regulation of nitric oxide synthase-type 2 (NOS-2) expression. Our study revealed that a specific gut inflammatory reaction results in inhibition of NOS-2 expression. Characteristics of this inhibition are: 1) local jejunal inflammation induced by T. spiralis systemically inhibits NOS-2 gene transcription, protein expression, and enzyme activity; 2) the inhibition blunts endotoxin-stimulated NOS-2 expression; 3) the inhibition does not extend to the expression of other isoforms of NOS, to paxillin, a housekeeper protein, or to cyclooxygenase-2, another protein induced by proinflammatory cytokines; 4) the inhibition is unlikely related to the formation of specific anti-parasite antibodies; and 5) the inhibition may involve substances other than stress-induced corticosteroids. Elucidation of such potent endogenous NOS-2 down-regulatory mechanisms could lead to the development of new strategies for the therapy of inflammatory conditions characterized by the overproduction of NO.
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Jia Z, Ramstad T, Zhong M. Medium-throughput pKa screening of pharmaceuticals by pressure-assisted capillary electrophoresis. Electrophoresis 2001; 22:1112-8. [PMID: 11358135 DOI: 10.1002/1522-2683()22:6<1112::aid-elps1112>3.0.co;2-1] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A fast screening method for the determination of the dissociation constants (pKa) of acidic, basic, and multivalent compounds was developed by using pressure-assisted capillary electrophoresis (PACE). External air pressure was applied to shorten the analysis time. The separation efficiency decreases as air pressure increases. However, it was found that air pressure does not affect the measurement of electrophoretic mobility and pKa significantly when it is less than 2 psi. The method was evaluated in terms of accuracy, precision, and ruggedness by using a set of 48 compounds with literature pKa values ranging from 2 to 10. The difference between the measured pKa values and literature values is less than 0.2 units. The throughput is approximately 20 compounds per day with a 12-point measurement ranging from pH 2.5 to 11. It was demonstrated that this method is applicable for pKa screening of pharmaceuticals with diverse chemical structures.
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143
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Xuan D, Zhong M, Mattoes H, Bui KQ, McNabb J, Nicolau DP, Quintiliani R, Nightingale CH. Streptococcus pneumoniae response to repeated moxifloxacin or levofloxacin exposure in a rabbit tissue cage model. Antimicrob Agents Chemother 2001; 45:794-9. [PMID: 11181363 PMCID: PMC90376 DOI: 10.1128/aac.45.3.794-799.2001] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The role of moxifloxacin and levofloxacin pharmacokinetics (PK) in antimicrobial efficacy and in the selection of fluoroquinolone-resistant Streptococcus pneumoniae strains was investigated using the rabbit tissue cage abscess model. A rabbit tissue cage was created by insertion of sterile Wiffle balls in the dorsal cervical area. Animals orally received a range of moxifloxacin or levofloxacin doses that simulate human PK for 7 days 48 h after the Wiffle balls were inoculated with fluoroquinolone-sensitive S. pneumoniae (10(7) CFU). Abscess fluid was collected on a daily basis over 14 days to measure bacterial density and MICs. Moxifloxacin regimens produced a range of area under the concentration-time curve (AUC)/MIC ratios ranging from 9.2 to 444 and peak/MIC ratios ranging from 1.3 to 102. Levofloxacin doses produced AUC/MIC ratios of 5.1 to 85.5 and peak/MIC ratio of 0.9 to 14.8. Moxifloxacin at 6.5, 26, and 42 mg/kg reduced the bacterial log CFU per milliliter in abscess fluid (percentage of that in a sterile animal) by 4.2 +/- 2.2 (20%), 5.8 +/- 0.4 (100%), and 5.4 +/- 0.4 (100%), respectively, over the dosing period. Levofloxacin at 5.5, 22, and 32 mg/kg reduced the log CFU per milliliter in abscess fluid (percentage of that in a sterile animal) by 2.8 +/- 0.7 (20%), 5.1 +/- 1.3 (80%), and 4.6 +/- 1.3 (60%), respectively. Moxifloxacin has a greater bactericidal rate as determined by regression of log CFU versus time data. The AUC/MIC and peak/MIC ratios correlated with the efficacy of both drugs (P < 0.05). Resistance to either drug did not develop with any of the doses as assessed by a change in the MIC. In conclusion, data derived from this study show that moxifloxacin and levofloxacin exhibit rapid bactericidal activity against S. pneumoniae in vivo, and moxifloxacin exhibits enhanced bactericidal activity compared to levofloxacin, with AUC/MIC and peak/MIC ratios correlated with antimicrobial efficacy for both drugs. The development of fluoroquinolone-resistant S. pneumoniae was not observed with either drug in this model.
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144
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Collman JP, Zhong M, Zeng L, Costanzo S. The [Cu(OH).TMEDA]2Cl2-catalyzed coupling of arylboronic acids with imidazoles in water. J Org Chem 2001; 66:1528-31. [PMID: 11312997 DOI: 10.1021/jo0016780] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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145
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Grant EM, Zhong M, Fitzgerald JF, Nicolau DP, Nightingale C, Quintiliani R. Lack of interaction between levofloxacin and oxycodone: pharmacokinetics and drug disposition. J Clin Pharmacol 2001; 41:206-9. [PMID: 11210403 DOI: 10.1177/00912700122009890] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Previous studies have demonstrated a significant reduction in the oral bioavailability of trovafloxacin and ciprofloxacin when administered concomitantly with an intravenous opiate such as morphine. This decrease in absorption results in a 36% and 50% lower AUC for trovafloxacin and ciprofloxacin, respectively, which could cause clinical failures. The authors investigated the possibility of a similar interaction between oxycodone and levofloxacin. Eight healthy volunteers were randomized in an open-label, two-way crossover study to receive oxycodone, 5 mg p.o. Q4H, and levofloxacin, 500 mg p.o. 1 hour after starting the oxycodone or levofloxacin 500 mg p.o. alone. Blood samples were drawn at 0, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 18, and 24 hours for Cmax, tmax, and AUC determinations. There was not a significant difference (p > 0.05) in AUC (48.59 +/- 8.52 vs. 49.9 +/- 9.93), Cmax (7.73 +/- 2.6 vs. 6.6 +/- 2.0), and tmax (1.1 +/- 0.6 vs. 1.6 +/- 1.1) for levofloxacin versus levofloxacin/oxycodone regimens. It was concluded that oral oxycodone and levofloxacin can be administered concomitantly without a significant decrease in AUC, Cmax, or tmax.
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146
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Basak A, Zhong M, Munzer JS, Chrétien M, Seidah NG. Implication of the proprotein convertases furin, PC5 and PC7 in the cleavage of surface glycoproteins of Hong Kong, Ebola and respiratory syncytial viruses: a comparative analysis with fluorogenic peptides. Biochem J 2001; 353:537-45. [PMID: 11171050 PMCID: PMC1221599 DOI: 10.1042/0264-6021:3530537] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Fluorogenic peptides encompassing the processing sites of envelope glycoproteins of the infectious influenza A Hong Kong virus (HKV), Ebola virus (EBOV) and respiratory syncytial virus (RSV) were tested for cleavage by soluble recombinants of the proprotein convertases furin, PC5 and PC7. Kinetic studies with these intramolecularly quenched fluorogenic peptides revealed selective cleavages at the physiological dibasic sites. The HKV peptide is cleaved by both furin and PC5 with similar efficacy; in comparison, PC7 cleaves this substrate poorly. In contrast with the basic tetrapeptide insertion within the haemagglutinin sequence of HKV, two other dipeptide insertions revealed a poorer cleavage with a similar rank order of potency. These results demonstrate that the N-terminal RERR insertion to the wild-type avian RKKR downward arrow sequence is functionally significant, and suggest that the approx. 5-fold increase in cleavage efficacy contributes to the high infectivity of the H5N1 virus subtype. With regard to RSV peptide processing, PC7 is twice as effective as PC5 and furin. The EBOV peptide was processed with similar efficiency by the three enzymes. Our observations that all of these cleavages can be effectively inhibited by a plant andrographolide derivative at 250 microM or less might aid in the design of potent convertase inhibitors as alternative antiviral therapies.
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147
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Zhang QH, Ye M, Wu XY, Ren SX, Zhao M, Zhao CJ, Fu G, Shen Y, Fan HY, Lu G, Zhong M, Xu XR, Han ZG, Zhang JW, Tao J, Huang QH, Zhou J, Hu GX, Gu J, Chen SJ, Chen Z. Cloning and functional analysis of cDNAs with open reading frames for 300 previously undefined genes expressed in CD34+ hematopoietic stem/progenitor cells. Genome Res 2000; 10:1546-60. [PMID: 11042152 PMCID: PMC310934 DOI: 10.1101/gr.140200] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2000] [Accepted: 07/19/2000] [Indexed: 11/24/2022]
Abstract
Three hundred cDNAs containing putatively entire open reading frames (ORFs) for previously undefined genes were obtained from CD34+ hematopoietic stem/progenitor cells (HSPCs), based on EST cataloging, clone sequencing, in silico cloning, and rapid amplification of cDNA ends (RACE). The cDNA sizes ranged from 360 to 3496 bp and their ORFs coded for peptides of 58-752 amino acids. Public database search indicated that 225 cDNAs exhibited sequence similarities to genes identified across a variety of species. Homology analysis led to the recognition of 50 basic structural motifs/domains among these cDNAs. Genomic exon-intron organization could be established in 243 genes by integration of cDNA data with genome sequence information. Interestingly, a new gene named as HSPC070 on 3p was found to share a sequence of 105bp in 3' UTR with RAF gene in reversed transcription orientation. Chromosomal localizations were obtained using electronic mapping for 192 genes and with radiation hybrid (RH) for 38 genes. Macroarray technique was applied to screen the gene expression patterns in five hematopoietic cell lines (NB4, HL60, U937, K562, and Jurkat) and a number of genes with differential expression were found. The resource work has provided a wide range of information useful not only for expression genomics and annotation of genomic DNA sequence, but also for further research on the function of genes involved in hematopoietic development and differentiation.
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148
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Laaksonen R, Lefebvre C, Lavigne J, Priceputu E, Bernier L, Davignon J, Mowla S, Bergeron E, Munzer J, Zhong M, Chretien M, Marcinkiewicz M, Seidah N. Inhibition of sterol regulatory element-binding protein cleavage by the prodomain of human SKI-1 protease. Atherosclerosis 2000. [DOI: 10.1016/s0021-9150(00)81302-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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149
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Song ZH, Zhong M. CB1 cannabinoid receptor-mediated cell migration. J Pharmacol Exp Ther 2000; 294:204-9. [PMID: 10871313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Recent studies have suggested that cell migratory responses are often mediated by G(i) protein-coupled receptors. Because it is known that CB1 cannabinoid receptors are coupled to pertussis toxin-sensitive G proteins, we proposed that CB1 may mediate cell migration. To test this hypothesis, modified Boyden chamber assays were used to investigate cell migration mediated by CB1 cannabinoid receptors. HU-210, WIN55212-2, and anandamide, three cannabinoid agonists with distinct chemical structures, induced migration of human embryonic kidney 293 cells stably transfected with human CB1 gene, but not 293 cells transfected with an empty expression vector. These migratory responses were concentration-dependent. The EC(50) values for HU-210, WIN55212-2, and anandamide were 0.19 +/- 0.04, 12. 2 +/- 1.4, and 39.9 +/- 3.7 nM, respectively. The maximal migration index for HU-210, WIN55212-2, and anandamide were 8.9 +/- 1.6, 9.5 +/- 1.6, and 8.8 +/- 1.3, respectively. Pretreating cells with 100 ng/ml pertussis toxin eliminated the cannabinoid agonist-induced cell migration. SR141716A, a selective antagonist for CB1, inhibited the cannabinoid agonist-induced migratory responses in a concentration-dependent manner. Checkerboard analysis demonstrated that anandamide-induced cell migrations are due to chemotaxis as well as chemokinesis. Furthermore, anandamide-induced migratory responses were inhibited, in a concentration-dependent manner, by PD098059, an inhibitor of mitogen-activated protein kinase activation, but not by 8-bromoadenosine-3',5'-cyclic monophosphate, a cell-permeable cAMP analog. These data demonstrate that cannabinoid agonists are able to induce chemotaxis and chemokinesis, and that these migratory responses are mediated by G protein-coupled, CB1 cannabinoid receptors. In addition, these data suggest that activation of mitogen-activated protein kinase plays an important role, whereas inhibition of adenylate cyclase is probably not involved in the cell migration mediated by CB1.
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Zhong M. [Study on the spectrophotometric determination of vanadium with piperonal fluorone by atomic absorption spectrophotometer]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:385-387. [PMID: 12958965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A spectrophotometric method for the determination of vanadium with piperonal fluorone (PIF) has been studied with the aid of continuous light sources and an atomic absorption spectrophotometer, and satisfactory results have been obtained in the determination of vanadium in steel.
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