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Li XX, Yang XG, Lu YQ, Lu SS, Zhang M, Yao HI, Meng LJ, Lu KH. Protective effects of melatonin against oxidative stress in flow cytometry-sorted buffalo sperm. Reprod Domest Anim 2011; 47:299-307. [PMID: 21790800 DOI: 10.1111/j.1439-0531.2011.01858.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Previous reports of the ability of melatonin to scavenge a variety of toxic oxygen and nitrogen-based reactants suggest that melatonin could be an effective antioxidant for protecting sperm. In this study, flow cytometry and laser tweezers Raman spectroscopy were used to evaluate the effect of melatonin on buffalo sperm quality to optimize sperm sex-sorting procedures. In fresh sperm incubated in the presence or absence of melatonin (10(-4) m) for 1, 24, 48 h or 72 h at 27°C, the mitochondrial activity was significantly higher than in a non-melatonin control (p < 0.05). Also, during the flow-sorting process, sperm in melatonin-supplemented groups had higher (p < 0.05) mitochondrial activity than the control. The intensity of Raman spectra from sperm frozen in media supplemented with melatonin was significantly weaker than that for non-melatonin-treated groups, except for a band at 1302 per cm. Thus, melatonin helps to protect buffalo sperm from reactive oxygen species induced by staining, sorting and freezing and increases semen quality after the freezing-thawing processes. Furthermore, the results indicate the high potential of the laser tweezers Raman spectroscopy technique for rapid, effective and non-invasive assessment of the quality of sperm cells.
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Zhang M, Westerly DC, Mackie TR. Introducing an on-line adaptive procedure for prostate image guided intensity modulate proton therapy. Phys Med Biol 2011; 56:4947-65. [PMID: 21772078 DOI: 10.1088/0031-9155/56/15/019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
With on-line image guidance (IG), prostate shifts relative to the bony anatomy can be corrected by realigning the patient with respect to the treatment fields. In image guided intensity modulated proton therapy (IG-IMPT), because the proton range is more sensitive to the material it travels through, the realignment may introduce large dose variations. This effect is studied in this work and an on-line adaptive procedure is proposed to restore the planned dose to the target. A 2D anthropomorphic phantom was constructed from a real prostate patient's CT image. Two-field laterally opposing spot 3D-modulation and 24-field full arc distal edge tracking (DET) plans were generated with a prescription of 70 Gy to the planning target volume. For the simulated delivery, we considered two types of procedures: the non-adaptive procedure and the on-line adaptive procedure. In the non-adaptive procedure, only patient realignment to match the prostate location in the planning CT was performed. In the on-line adaptive procedure, on top of the patient realignment, the kinetic energy for each individual proton pencil beam was re-determined from the on-line CT image acquired after the realignment and subsequently used for delivery. Dose distributions were re-calculated for individual fractions for different plans and different delivery procedures. The results show, without adaptive, that both the 3D-modulation and the DET plans experienced delivered dose degradation by having large cold or hot spots in the prostate. The DET plan had worse dose degradation than the 3D-modulation plan. The adaptive procedure effectively restored the planned dose distribution in the DET plan, with delivered prostate D(98%), D(50%) and D(2%) values less than 1% from the prescription. In the 3D-modulation plan, in certain cases the adaptive procedure was not effective to reduce the delivered dose degradation and yield similar results as the non-adaptive procedure. In conclusion, based on this 2D phantom study, by updating the proton pencil beam energy from the on-line image after realignment, this on-line adaptive procedure is necessary and effective for the DET-based IG-IMPT. Without dose re-calculation and re-optimization, it could be easily incorporated into the clinical workflow.
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Meng LQ, Tang JW, Wang Y, Zhao JR, Shang MY, Zhang M, Liu SY, Qu L, Cai SQ, Li XM. Astragaloside IV synergizes with ferulic acid to inhibit renal tubulointerstitial fibrosis in rats with obstructive nephropathy. Br J Pharmacol 2011; 162:1805-18. [PMID: 21232035 PMCID: PMC3081123 DOI: 10.1111/j.1476-5381.2011.01206.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE The combination of Chinese herbs, Astragali Radix and Angelicae Sinensis Radix, could alleviate renal interstitial fibrosis. Astragaloside IV (AS-IV) and ferulic acid (FA) are the two major active constituents in this combination. In this study, we employed rats with unilateral ureteral obstruction to determine whether AS-IV and FA have the same renoprotective effects and investigated the mechanisms of this action. EXPERIMENTAL APPROACH Renal pathological changes were evaluated after treatment with AS-IV, FA or AS-IV + FA (AF) for 10 days. Meanwhile, the expression of transforming growth factor β1 (TGF-β1), fibronectin, α-smooth muscle actin (α-SMA), phosphorylation of c-Jun NH2-terminal kinase (p-JNK) and nitric oxide (NO) production in kidney were determined. The expressions of fibronectin, α-SMA, mitogen-activated protein kinases [JNK, extracellular signal-regulated kinases (ERK), P38] in TGF-β1-treated NRK-49F cells or interleukin-1-treated HK-2 cells after AS-IV, FA or AF were assessed. KEY RESULTS AF alleviated the infiltration of mononuclear cells, tubular atrophy and interstitial fibrosis; reduced the expression of fibronectin, α-SMA, TGF-β1 and p-JNK; and dramatically increased the production of NO in obstructed kidneys. Neither AS-IV nor FA alone improved renal damage, but both increased NO production. AF inhibited α-SMA and fibronectin expression in NRK-49F or HK-2 cells. Furthermore, AF significantly inhibited IL-1β-induced JNK phosphorylation, without affecting ERK or P38 phosphorylation. Neither AS-IV nor FA alone had any effect on the cells. CONCLUSIONS AND IMPLICATIONS AS-IV synergizes with FA to alleviate renal tubulointerstitial fibrosis; this was associated with inhibition of tubular epithelial–mesenchymal transdifferentiation (EMT) and fibroblast activation, as well as an increase in NO production in the kidney.
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Cao X, Zhang W, Ma S, Zhang M, Wang J, Ye T. Enhanced antitumor effects of tumor antigen-pulsed dendritic cells by their transfection with GM-CSF gene. ACTA ACUST UNITED AC 2011; 40:539-45. [PMID: 20229307 DOI: 10.1007/bf03183594] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/1996] [Indexed: 12/27/2022]
Abstract
To investigate the biological characterization and antitumor activities of GM-CSF gene-transfected dendritic cells, the splenic dendritic cells were infected with GM-CSF recombinant replication-deficient adenovirusesin vitro. Their enhanced expression of B7 was demonstrated by FACS analysis, and more potent stimulatory activity was confirmed by allogeneic MLR. Immunization of dendritic cells pulsed with irradiated B16 melanoma cells induced significant CTL and enabled host to resist the challenge of wild-type B16 cells. When they were transfected with GM-CSF gene subsequently, the induced CTL activity was higher, and the produced protection against B16 cell challenge and therapeutic effect on the mice with preestablished pulmonary metastases more effective. These data suggest that the dendritic cells pulsed with tumor antigen then transfected with GM-CSF gene can be used as an effective vaccine in tumor immunotherapy.
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Zhang M, Mo X, Levinson L, Goyal S, Yue N. SU-E-T-691: On the Use of Multiple Beam Angles to Minimize the Impact of High Density Fiducial Markers in the Prostate Proton Radiotherapy. Med Phys 2011. [DOI: 10.1118/1.3612653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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1381
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Pang E, Delic N, Hong A, Zhang M, Rose B, Lyons J. O48. Radiation-induced cell death of keratinocytes is enhanced by HPV16 oncoprotein E6∗I: A possible mechanism for the improved clinical outcome of HPV positive oropharyngeal squamous cell carcinoma patients. Oral Oncol 2011. [DOI: 10.1016/j.oraloncology.2011.06.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hong A, Rose B, Lee S, Jones D, Martin A, Zhang M. P54. Human papillomavirus, smoking and outcomes in tonsillar squamous cell carcinoma. Oral Oncol 2011. [DOI: 10.1016/j.oraloncology.2011.06.297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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1383
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Wang J, Xiao Y, Lu Y, Kang Z, Zhang M, Liu Y, Liang J, Zhang M, Li T. Pharmacokinetics of antofloxacin hydrochloride in healthy male subjects after multiple intravenous dose administration. Xenobiotica 2011; 41:561-6. [PMID: 21446836 DOI: 10.3109/00498254.2011.565820] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The purpose of the study was to evaluate pharmacokinetic characteristics of antofloxacin hydrochloride, a new fluoroquinolone antibiotic, during a multiple, intravenous dosing regimen. Twelve healthy, Chinese male volunteer subjects were each given 300 mg of antofloxacin by intravenous infusion once daily for 7 days. Blood and urine samples were taken at designated time points for analysis of antofloxacin concentration by high-performance liquid chromatography (HPLC). Safety and tolerability were assessed by evaluation of subject complaints, vital signs, electrocardiograms, electroencephalograms, clinical chemistry parameters, haematology and urinalysis and prothrombin time. The serum steady concentration of antofloxacin was obtained in 96 h after the administration of a daily intravenous dose of 300 mg of the drug. In the present study, the following pharmacokinetic parameters after 7 days of treatment with antofloxacin were determined to be: C(max) 3.81 ± 0.66 mg/L, C(min) 0.85 ± 0.19 mg/L, AUC(0-24) 60.51 ± 8.30 mg/L·h, C(av) 2.52 ± 0.35 mg/L, PTF 87.45 ± 3.37%, t(1/2)β 20.34 ± 1.88 h. The C(max) and AUC(0-24) after 7-day treatment were both higher than after the first dose (by 43% and 110%, respectively). The cumulative urinary elimination of antofloxacin within 96 h after the last dose was about 56%. During the study, there were neither subject complaints nor significant adverse clinical findings. Antofloxacin, administered intravenously as a single, daily 300 mg dose for 7 days, demonstrated favourable pharmacokinetic characteristics and tolerability. The results of this study indicate that antofloxacin hydrochloride is suitable for further clinical study.
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Zhang M, Matsuo K, Yamashita Y, Takahashi T. Leiomyomatous hamartoma of the midline maxillary gingival presenting as a congenital epulis: a case report with an immunohistochemical study. Int J Oral Maxillofac Surg 2011; 40:1322-6. [PMID: 21696920 DOI: 10.1016/j.ijom.2011.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 04/04/2011] [Accepted: 05/10/2011] [Indexed: 11/24/2022]
Abstract
An otherwise-healthy 2-year-old Japanese female presented with a polyp-like lesion on the palatal surface at the incisive papilla. The appearance of the lesion was similar to that of a congenital epulis. The histological findings showed proliferating mesenchymal components that contained mainly smooth muscle admixed with collagen fibres, nerve fibres, small vessels and mucous salivary glands. The immunohistochemical staining findings for α-smooth-muscle actin, desmin and S-100 protein were all positive. The histological diagnosis was therefore leiomyomatous hamartoma, based on clinical microscopic observations.
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Gao EJ, Liu SH, Sun TD, Lin L, Wang RS, Zhang YX, Su M, Zhang M. Synthesis and characterization of a novel coordination polymer {[Mn(L)(Phen)2] · 2H2O} n 1. RUSS J COORD CHEM+ 2011. [DOI: 10.1134/s1070328411050046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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1386
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Chen T, Levinson L, Zhang M, Goyal S, Haffty B, Yue N. SU-E-T-238: OnedosePlus MOSFET Dosimeter Performance in Tangential Field in Vivo Dosimtery. Med Phys 2011. [DOI: 10.1118/1.3612188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Zhang M, O’Donoghue M, Ito T, Hiramatsu K, Boost M. Prevalence of antiseptic-resistance genes in Staphylococcus aureus and coagulase-negative staphylococci colonising nurses and the general population in Hong Kong. J Hosp Infect 2011; 78:113-7. [DOI: 10.1016/j.jhin.2011.02.018] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 02/25/2011] [Indexed: 11/26/2022]
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1388
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Mo X, Westerly D, Zhang M, Mackie T. TH-C-BRB-07: Treatment Planning with Multiple Spot Sizes to Improve Delivery Efficiency in Intensity Modulated Proton Therapy. Med Phys 2011. [DOI: 10.1118/1.3613512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Palermo A, Palmer R, So K, Zhang M, Richards B, Shah S, Finn P, Oba-Shinjo S, Pescatori M, Marie S, McVie-Wylie A, Mattaliano R, Pomponio R, Madden S, Klinger K. Transcriptional Response to GAA Deficiency in Mice and Humans. Clin Ther 2011. [DOI: 10.1016/j.clinthera.2011.05.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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1390
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Gopalan PK, Baz MA, Zajac-Kaye M, Cao C, Gordillo-Villegas A, Zhang M, Lu L, Kaye FJ. Increased risk of neuroendocrine (NE) carcinoma in single-lung transplant survivors. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e21131] [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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1391
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Zhang M, Zhao J, Tong W, Wang A, Huang G, Zhang Y. Associations between metabolic syndrome and its components and alcohol drinking. Exp Clin Endocrinol Diabetes 2011; 119:509-12. [PMID: 21553359 DOI: 10.1055/s-0031-1277138] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AIMS The relationship between alcohol drinking and metabolic syndrome (MetS) and its components are not fully confirmed, we examined relationship between alcohol drinking and MetS and its components. METHODS 2,538 Mongolian people aged 20 or more were included in this study. The data for demographic characteristics, lifestyle factors, family history of hypertension, blood pressure (BP) measurements and physical examination were obtained, and fasting plasma glucose (FPG) and lipids examined for all participants. Associations between MetS and its components and alcohol drinking were analyzed with Logistic regression. RESULTS The risks of MetS associated with alcohol drinking and various drinking volume were not significant after adjustment for other variables. Alcohol drinking was significantly and positively associated with high BP and high TG, the multivariate adjusted OR (95% CI) of high BP and high TG for drinking were 1.399(1.109, 1.764) and 2.464(1.866, 3.252), respectively, compared with no drinking. However, drinking was inversely associated with low HDL-C, the multivariate adjusted OR (95% CI) of low HDL-C was 0.597(0.479, 0.745) for alcohol drinking compared with no drinking. CONCLUSIONS Alcohol drinking was significantly and positively associated with high BP and high TG, while alcohol drinking inversely associated with low HDL-C.
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Gao EJ, Wang Y, Zhu MC, Liu L, Wen Z, Gao XN, Sun TD, Liu SH, Su M, Zhang YX, Zhang M, Zhang Y. Synthesis and crystal structure of a coordination polymer {[Cu2(L)2(Phen)2] · 8H2O} n. RUSS J COORD CHEM+ 2011. [DOI: 10.1134/s107032841104004x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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1393
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Li J, Wang YJ, Zhang M, Xu ZQ, Gao CY, Fang CQ, Yan JC, Zhou HD. Vascular risk factors promote conversion from mild cognitive impairment to Alzheimer disease. Neurology 2011; 76:1485-91. [PMID: 21490316 DOI: 10.1212/wnl.0b013e318217e7a4] [Citation(s) in RCA: 248] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Growing evidence suggests that vascular risk factors (VRF) contribute to cognitive decline. The aim of this study was to investigate the impact of VRF on the conversion from mild cognitive impairment (MCI) to Alzheimer disease (AD) dementia. METHODS A total of 837 subjects with MCI were enrolled at baseline and followed up annually for 5 years. The incidence of AD dementia was investigated. A mixed random effects regression model was used to analyze the association between VRF and the progression of MCI assessed with Mini-Mental State Examination and instrumental Activities of Daily Living. Cox proportional hazard models were used to identify the association between VRF and dementia conversion, and to examine whether treatment of VRF can prevent dementia conversion. RESULTS At the end of the follow-up, 298 subjects converted to AD dementia, while 352 remained MCI. Subjects with VRF had a faster progression in cognition and function relative to subjects without. VRF including hypertension, diabetes, cerebrovascular diseases, and hypercholesterolemia increased the risk of dementia conversion. Those subjects with MCI in whom all VRF were treated had a lower risk of dementia than those who had some VRF treated. Treatment of individual VRF including hypertension, diabetes, and hypercholesterolemia was associated with the reduced risk of AD conversion. CONCLUSION VRF increased the risk of incident AD dementia. Treatment of VRF was associated with a reduced risk of incident AD dementia. Although our findings are observational, they suggest active intervention for VRF might reduce progression in MCI to AD dementia.
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Gao EJ, Liu SH, Zhang M, Lin L, Wang RS, Sun TD, Wang Y, Wen Z. Synthesis and molecular characterization of the coordination polymer [Pb(2,2′-Bipy)(NO3)2(H2O)] n. RUSS J COORD CHEM+ 2011. [DOI: 10.1134/s1070328411030043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Wu L, Zhang M, Sun M, Jia B, Wang X. Humoural Immune Responses to a Recombinant 16-kDa–38-kDa—ESAT-6 Mycobacterial Antigen in Tuberculosis. J Int Med Res 2011; 39:514-21. [PMID: 21672355 DOI: 10.1177/147323001103900219] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The present study investigated the diagnostic value of a recombinant 38-kDa–16-kDa—early secreted antigenic target of 6 kDa (ESAT-6) Mycobacterium tuberculosis (MTB) fusion antigen in 105 patients with tuberculosis (TB), 25 non-TB pulmonary disease patients and 20 healthy individuals. Its diagnostic value was compared with the commercially available enzyme-linked immunosorbent assay kit, the TB-directly observed therapy (DOT) kit. In the controls, the rate of positive antibody response to the TB-DOT kit was significantly higher than that of the recombinant antigen. The area under the receiver operating characteristic curve was 0.751, and the optimum sensitivity and specificity for detecting antibody responses to the recombinant antigen were 65.4% and 84.8%, respectively. The recombinant 38-kDa–16-kDa—ESAT-6 MTB antigen was more effective than the TB-DOT kit in distinguishing between TB patients and controls, and may be an optimal combination of antigens to provide a useful tool for the sensitive and specific diagnosis of patients with TB.
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Zhang M, Liu S, Yin XM, Du ZF, Hao QY, Lei DN, Li QH, Wang TH. Fast Synthesis of Graphene Sheets with Good Thermal Stability by Microwave Irradiation. Chem Asian J 2011; 6:1151-4. [DOI: 10.1002/asia.201000776] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2010] [Indexed: 11/06/2022]
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Ferrari M, Chu IW, Desai IT, Hansford D, Mazzoni G, Huen T, Zhang M. Silicon Nanotechnology for Biofiltration and Immunoisolated Cell Xenografts. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-414-101] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractSilicon-based clean-room technology is employed for the microfabrication of a particle filter with uniform pore dimensions in the 20-40-nm range. Surface and bulk micromachining are integrated in the fabrication process, resulting in a filtering membrane with large active area, flow rate and resistance to pressure. The microfabricated membrane is especially suitable for biofluid purification, including viral elimination. The nanofilter is a technological precursor for a microfabricated, silicon-based capsule to be employed in the reaction-free xenotransplantation of cells. Results are presented below that address the issue of biocompatibility of the microfabricated capsule components and materials.
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Kumar A, Oskouian B, Fyrst H, Zhang M, Paris F, Saba JD. S1P lyase regulates DNA damage responses through a novel sphingolipid feedback mechanism. Cell Death Dis 2011; 2:e119. [PMID: 21368890 PMCID: PMC3101703 DOI: 10.1038/cddis.2011.3] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The injurious consequences of ionizing radiation (IR) to normal human cells and the acquired radioresistance of cancer cells represent limitations to cancer radiotherapy. IR induces DNA damage response pathways that orchestrate cell cycle arrest, DNA repair or apoptosis such that irradiated cells are either repaired or eliminated. Concomitantly and independent of DNA damage, IR activates acid sphingomyelinase (ASMase), which generates ceramide, thereby promoting radiation-induced apoptosis. However, ceramide can also be metabolized to sphingosine-1-phosphate (S1P), which acts paradoxically as a radioprotectant. Thus, sphingolipid metabolism represents a radiosensitivity pivot point, a notion supported by genetic evidence in IR-resistant cancer cells. S1P lyase (SPL) catalyzes the irreversible degradation of S1P in the final step of sphingolipid metabolism. We show that SPL modulates the kinetics of DNA repair, speed of recovery from G2 cell cycle arrest and the extent of apoptosis after IR. SPL acts through a novel feedback mechanism that amplifies stress-induced ceramide accumulation, and downregulation/inhibition of either SPL or ASMase prevents premature cell cycle progression and mitotic death. Further, oral administration of an SPL inhibitor to mice prolonged their survival after exposure to a lethal dose of total body IR. Our findings reveal SPL to be a regulator of ASMase, the G2 checkpoint and DNA repair and a novel target for radioprotection.
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Maiti S, Zhang M, Bernatchez C, Torikai H, Kellar D, Gibbons H, Hernandez J, Andersson H, Huls H, Lee D, Hwu P, Radvanyi L, Cooper L. Digital Multiplexed Quantification of Both T-Cell Receptor β-Chain and α-Chain Diversity in T Cells Using the Nanostring nCounter Assay System. Biol Blood Marrow Transplant 2011. [DOI: 10.1016/j.bbmt.2010.12.329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zhang M, Gao F, Cui X, Zhang Y, Sun Y, Gu J, Sun Y. Development and Validation of an Improved Method for the Quantitation of Sertraline in Human Plasma using LC-MS-MS and Its Application to Bioequivalence Studies. J Chromatogr Sci 2011; 49:89-93. [DOI: 10.1093/chrsci/49.2.89] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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