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Pistell PJ, Zhu M, Ingram DK. Acquisition of conditioned taste aversion is impaired in the amyloid precursor protein/presenilin 1 mouse model of Alzheimer's disease. Neuroscience 2008; 152:594-600. [PMID: 18304749 DOI: 10.1016/j.neuroscience.2008.01.025] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 01/16/2008] [Accepted: 01/21/2008] [Indexed: 11/25/2022]
Abstract
Research into the underlying mechanisms of cognitive dysfunction in Alzheimer's disease (AD) has relied traditionally on tasks such as the water maze which evaluate spatial learning and memory. Since non-spatial forms of memory are also disrupted by AD, it is critical to establish other paradigms capable of investigating these deficits. Utilizing a non-spatial learning task, acquisition of conditioned taste aversion (CTA) was evaluated in a mouse model of AD. This line of transgenic mice encode a mutated allele of the human amyloid precursor protein (APP) and presenilin 1 (PS1) genes and exhibit extensive amyloid plaque deposition in the brain by 6-7 mo of age. Compared with wild-type mice, 10-17 month old APP/PS1 mice failed to acquire CTA to saccharin. Mice that only possessed one of the two mutations were able to acquire CTA to the saccharin. In 2-5 month old APP/PS1 mice acquisition of CTA was disrupted despite the lack of extensive plaque deposition. However, further analysis indicated a potential gender difference in both the CTA deficit and onset of plaque deposition with females showing greater conditioned aversion.
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Zhu M, Chen M, Lichtler AC, O'Keefe RJ, Chen D. Tamoxifen-inducible Cre-recombination in articular chondrocytes of adult Col2a1-CreER(T2) transgenic mice. Osteoarthritis Cartilage 2008; 16:129-30. [PMID: 17888690 PMCID: PMC2271067 DOI: 10.1016/j.joca.2007.08.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 08/04/2007] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the specificity and efficiency of the tamoxifen (TM)-induced Cre-recombination in articular chondrocytes of adult Col2a1-CreER(T2) transgenic mice. METHODS Col2a1-CreER(T2) transgenic mice were bred with Rosa26 reporter mice. Two-week-old Col2a1-CreER(T2);R26R mice were administered TM for 5 days and were sacrificed 1 and 6 months after TM induction. X-Gal staining was performed. RESULTS Efficient Cre-recombination is achieved in adult articular chondrocytes 1 and 6 months after TM induction. CONCLUSION Our findings demonstrate that the Col2a1-CreER(T2) transgenic mouse model is a valuable tool to target genes specifically expressed in articular chondrocytes in a temporally controlled manner in adult mice.
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Li W, Dai S, An J, Li P, Chen X, Xiong R, Liu P, Wang H, Zhao Y, Zhu M, Liu X, Zhu P, Chen JF, Zhou Y. Chronic but not acute treatment with caffeine attenuates traumatic brain injury in the mouse cortical impact model. Neuroscience 2007; 151:1198-207. [PMID: 18207647 DOI: 10.1016/j.neuroscience.2007.11.020] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 10/23/2007] [Accepted: 11/30/2007] [Indexed: 11/28/2022]
Abstract
Caffeine, the most consumed psychoactive drug and non-specific adenosine receptor antagonist, has recently been shown to exert a neuroprotective effect against brain injury in animal models of Parkinson's disease (PD) and stroke. However, the effects of caffeine on traumatic brain injury (TBI) are not known. In this study, we investigated the effects of acute and chronic caffeine treatment on brain injury in a cortical-impact model of TBI in mice. Following TBI, neurological deficits, cerebral edema, as well as inflammatory cell infiltration were all significantly attenuated in mice pretreated chronically (for 3 weeks) with caffeine in drinking water compared with the mice pretreated with saline. Furthermore, we found that chronic caffeine treatment attenuated glutamate release and inflammatory cytokine production, effects that were correlated with an upregulation of brain A1 receptor mRNA. By contrast, acute treatment with caffeine (i.p. injection, 30 min before TBI) was not effective in protecting against TBI-induced brain injury. These results suggest that chronic (but not acute) caffeine treatment attenuates brain injury, possibly by A1 receptor-mediated suppression of glutamate release and inhibition of excessive inflammatory cytokine production. These results highlight the potential benefit of chronic caffeine intake for preventing TBI and provide a rationale for the epidemiological investigation of the potential association between TBI and human caffeine intake.
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Fraser JK, Wulur I, Alfonso Z, Zhu M, Wheeler ES. Differences in stem and progenitor cell yield in different subcutaneous adipose tissue depots. Cytotherapy 2007; 9:459-67. [PMID: 17786607 DOI: 10.1080/14653240701358460] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Human adipose tissue has been shown to contain multipotent cells with properties similar to mesenchymal stromal cells. While there have been many studies of the biology of these cells, no study has yet evaluated issues associated with tissue harvest. METHODS Adipose tissue was obtained from the subcutaneous space of the abdomen and hips of 10 donors using both syringe and pump-assisted liposuction. Tissue was digested with collagenase and then assayed for the presence of different stem and progenitor cell types using clonogenic culture assays, including fibroblast colony-forming unit (CFU-F) and alkaline phosphatase-positive colony-forming unit (CFU-AP). Paired analysis of samples obtained from the same individual was used to compare harvest method and site. RESULTS Syringe suction provided significantly greater recovery of adipocytes and a non-significant trend towards improved recovery of cells in the adipocyte-depleted fraction. There was considerable donor-to-donor variation in stem cell recovery. However, paired analysis of tissue obtained from different subcutaneous sites in the same donor showed that tissue harvested from the hip yielded 2.3-fold more CFU-F/unit volume and a 7-fold higher frequency of CFU-AP than that obtained from the abdomen. These differences were statistically significant. DISCUSSION Harvest site influences the stem and progenitor cell content of subcutaneous adipose tissue.
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Nair D, Tan SY, Gan HW, Lim SF, Tan J, Zhu M, Gao H, Chua NH, Peh WL, Mak KH. The use of ambulatory tonometric radial arterial wave capture to measure ambulatory blood pressure: the validation of a novel wrist-bound device in adults. J Hum Hypertens 2007; 22:220-2. [PMID: 17992251 DOI: 10.1038/sj.jhh.1002306] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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306
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Sahoo N, Zhu X, Zhu M, Amos R, Kudchadker R, Johnson J, Arjomandy B, Lii M, Wu R, Gillin M. Analysis of the Accuracy of a Monitor Unit Calculation Procedure for Passively Scattered Proton Therapy Beams. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.2057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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307
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Lin A, Yan WH, Xu HH, Zhu M, Zhou MY. Analysis of the HFE gene (C282Y, H63D and S65C) mutations in a general Chinese Han population. ACTA ACUST UNITED AC 2007; 70:252-5. [PMID: 17661915 DOI: 10.1111/j.1399-0039.2007.00877.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hereditary hemochromatosis (HH) is one of the most common autosomal recessive genetic disorders of iron metabolism in white populations, which leads to inappropriately high iron absorption. C282Y, H63D, and S65C are three major missense mutations of the hemochromatosis gene (HFE). In the present study, C282Y, H63D, and S65C mutations in 395 normal Chinese Han populations from Zhejiang province were investigated. No C282Y, S65C mutations, and H63D homozygote was observed, while the genotype frequency of H63D heterozygote was 4.6% and the allelic frequency 2.3% in this population. This was the first report to analyze the prevalence of C282Y, H63D, and S65C mutations in the HFE gene in a Chinese Han population. Low incidence of the HFE gene mutations could be a reason for the rarity of HH in the Chinese Han population studied.
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308
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Wang K, Hu S, Jiang X, Zhu M, Jin B. Liver transplantation for patient with variant hepatic artery arising from right renal artery: a case report. Transplant Proc 2007; 39:1716-7. [PMID: 17580230 DOI: 10.1016/j.transproceed.2006.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2006] [Accepted: 11/01/2006] [Indexed: 11/21/2022]
Abstract
Abnormalities of recipient or donor vascular structures are common and associated with reconstructive difficulties in liver transplantation. A patient with a variant hepatic artery arising from right renal artery underwent modified piggyback liver transplantation in our center. The donor hepatic artery was anastomosed end-to-side to the recipient's middle colic artery. Graft function has remained excellent more than 1 year postoperatively.
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309
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Lin A, Yan WH, Xu HH, Tang LJ, Chen XF, Zhu M, Zhou MY. 14 bp deletion polymorphism in the HLA-G gene is a risk factor for idiopathic dilated cardiomyopathy in a Chinese Han population. ACTA ACUST UNITED AC 2007; 70:427-31. [PMID: 17854427 DOI: 10.1111/j.1399-0039.2007.00926.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Human leukocyte antigen (HLA) has been reported to be associated with the pathogenesis of autoimmune-associated idiopathic dilated cardiomyopathy (IDC). However, the HLA-G in this context is limited. In the current study, a total of 117 IDC patients and age and sex matched 401 unrelated healthy controls in a Chinese Han population were HLA-G genotyped for the 14 bp insertion and deletion polymorphism. IDC patients showed markedly increased frequencies of -14 bp/-14 bp genotype [Pc = 0.00049, odds ratio (OR) = 2.17] and -14 bp alleles (Pc = 4.1 x 10(-5), OR = 1.97) when compared with healthy controls. Whereas the frequencies of +14 bp/+14 bp genotype (Pc = 0.0036, OR = 0.35) and +14 bp alleles (Pc = 4.1 x 10(-5), OR = 0.51) were significantly lower in IDC. These data, for the first time, indicated that 14 bp insertion/deletion polymorphism in HLA-G gene could be a genetic risk factor for the susceptibility to IDC.
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310
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Lin A, Yan WH, Xu HH, Gan MF, Cai JF, Zhu M, Zhou MY. HLA-G expression in human ovarian carcinoma counteracts NK cell function. Ann Oncol 2007; 18:1804-9. [PMID: 17846022 DOI: 10.1093/annonc/mdm356] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Human leukocyte antigen-G (HLA-G) is an important immunotolerant which could be a part of the strategies applied by malignant cells applied to avoid host immunosurveillance. Aberrant expression of HLA-G has been found in ovarian carcinoma. The aim of this study was to evaluate the HLA-G expression in ovarian cancer tissues and to explore its function in vitro. MATERIALS AND METHODS HLA-G expression in 33 primary ovarian carcinoma tissues was analyzed using immunohistochemistry with the anti-HLA-G monoclonal antibody (mAb) 4H84. Furthermore, the function of HLA-G in NK cell cytotoxicity was determined in vitro by cloning and expression of HLA-G on the ovarian carcinoma cell OVCAR-3. RESULTS HLA-G expression was detected in 22/33 (66.7%) primary tumor tissues, but was absent in normal ovarian tissues (P<0.01). Cytotoxicity studies showed that HLA-G expression dramatically inhibits cell lyses by NK-92 cells (P<0.01), which could be restored by the anti-HLA-G conformational mAb 87G (P<0.01). CONCLUSION HLA-G was expressed in a significant number of primary ovarian carcinoma tissues, and HLA-G expression in OVCAR-3 could directly inhibit NK-92 cell lysis. Taken together, our results indicated that expression of HLA-G plays an important role in evasion of ovarian cancer cells from host immunosurveillance.
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311
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Tan HH, Tan AWH, Barkham T, Yan XY, Zhu M. Community-based study of acne vulgaris in adolescents in Singapore. Br J Dermatol 2007; 157:547-51. [PMID: 17655737 DOI: 10.1111/j.1365-2133.2007.08087.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND There are few studies on the prevalence of acne vulgaris among Asian teenagers. OBJECTIVES To determine the epidemiology of acne in teenagers in Singapore. METHODS A community-based cross-sectional study in 1045 adolescents aged 13-19 years. RESULTS Of these respondents, 88% identified themselves as having acne. Eight hundred and six of these respondents were examined by a dermatologist, and 51.4% were classified as having mild acne, 40% moderate acne and 8.6% severe acne. Isolation of Propionibacterium acnes was attempted in 262 subjects. Cultures were positive in 174 subjects, giving an isolation rate of 66.4%. Antibiotic-resistant strains of P. acnes were detected in 26 isolates (14.9%). Eleven of these 26 subjects (42%) had previously been treated or were presently on antibiotic treatment for acne, but the other 58% of students who had antibiotic-resistant strains of P. acnes did not give a history of prior antibiotic therapy. Teenagers expressed psychological distress over acne, and believed that hormonal factors, diet and hygiene were important factors in causing acne. CONCLUSIONS There is a need for accessible, accurate education on acne and its appropriate treatment.
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Liao M, Zhang L, Yang G, Zhu M, Wang D, Wei Q, Zou G, Chen D. Development of silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) genetic maps using microsatellite and AFLP markers and a pseudo-testcross strategy. Anim Genet 2007; 38:364-70. [PMID: 17614988 DOI: 10.1111/j.1365-2052.2007.01617.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) are two of the four most important pond-cultured fish species inhabiting the major river basins of China. In the present study, genetic maps of silver carp and bighead carp were constructed using microsatellite and AFLP markers and a two-way pseudo-testcross strategy. To create the maps, 60 individuals were obtained from a cross of a single bighead carp (female) and a single silver carp (male). The silver carp map consisted of 271 markers (48 microsatellites and 223 AFLPs) that were assembled into 27 linkage groups, of which 22 contained at least four markers. The total length of the silver carp map was 952.2 cM, covering 82.8% of the estimated genome size. The bighead carp map consisted of 153 markers (27 microsatellites and 126 AFLPs) which were organized into 30 linkage groups, of which 19 contained at least four markers. The total length of the bighead carp map was 852.0 cM, covering 70.5% of the estimated genome size. Eighteen microsatellite markers were common to both maps. These maps will contribute to discovery of genes and genetic regions controlling traits in the two species of carp.
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Razis E, Selviaridis P, Fletcher J, Labropoulos S, Caprioli R, Karkavelas G, Zhu M, Kalebic T, Norris J, Fountzilas G. Biochemical evidence of tumor response and measurable levels of the drug in glioblastoma tissue from patients treated with imatinib. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.2023] [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
2023 Background: Glioblastoma multiforme (GBM) carries a grave prognosis. There are phase I-II studies indicating that imatinib is active in GBM in pre-treated patients. To better understand the molecular basis of imatinib’s activity in this disease we performed a pharmacodynamic neoadjuvant study with imatinib in GBM. Methods: Patients underwent CT guided biopsy of their brain tumors. If diagnosed with GBM they were immediately treated with 7 days of imatinib 400mg po BID followed by either definitive surgery or, if that was not feasible, followed by re-biopsy. Corticosteroid dose was stable during this period and valproic acid was the only anti-epileptic drug allowed in order to avoid pharmacokinetic interaction with imatinib. Treatment after recovery was as per usual institutional policy. Pre and post treatment tissue specimens were analyzed by immunohistochemistry, proteomic technology and molecular biological methods. Pharmacokinetic studies were also performed. Results: Twenty patients were enrolled in 2 institutions with a median age of 64, of which 14 were male and 6 female. PS was 0 in 2, 1 in 9 and 2 in 9. Seventeen patients had pure GBM, 2 had mixed GBM with astrocytoma and one had anaplastic astrocytoma. Eighteen patients had stable disease on pre and post treatment MRI, one had progressed and one was not evaluable. Median survival was 6.2 months (1.1–18mo). Intact imatinib was quantified in the post treatment tissue specimens and correlations were made with serum imatinib levels per patient. No correlation was seen. Tissue specimens were analyzed by in situ MALDI mass spectroscopy and differential protein expression profiles were detected, when pre and post treatment specimens were compared. The identification of candidate proteins is ongoing. In 11 patients with evaluable, high-quality, matched pre and post imatinib biopsies, 4 had biochemical evidence of tumor response (decreased AKT or MAPK, or increased p27). In addition, 2 patients showed high-level EGFR activation, and one patient had high-level PDGFR activation. Conclusions: Treatment of GBM patients with imatinib results in measurable levels of the drug in the tumor. Potential indicators of biochemical response in a subset of patients were identified. No significant financial relationships to disclose.
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Ding X, Bues M, Zhu M, Gaza R, Smith A. SU-FF-T-291: Measurement of the Mechanical Isocenter of a Proton Gantry. Med Phys 2007. [DOI: 10.1118/1.2760953] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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315
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Wang T, Fu F, Han B, Yu X, Zhu M, Zhang L. Effect of hydroxysafflor yellow a combined with nitroglycerin on acute myocardial infarction. J Mol Cell Cardiol 2007. [DOI: 10.1016/j.yjmcc.2007.03.653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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316
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Rajesh H, Yong YY, Zhu M, Chia D, Yu SL. Growth hormone deficiency and supplementation at in-vitro fertilisation. Singapore Med J 2007; 48:514-8. [PMID: 17538748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
INTRODUCTION This study aims to evaluate the differences in oocyte stimulation, endometrial thickness, fertilisation rate and embryo quality at in-vitro fertilisation (IVF) in patients with documented growth hormone (GH) deficiency, after GH supplementation. METHODS This was a retrospective analysis of 20 cases of patients who were pregnant and had GH supplementation during IVF at the Singapore General Hospital between 1993 and 2003. All these patients had previously failed IVF due to poor stimulation, poor egg quality, poor fertilisation at intracytoplasmic sperm injection (ICSI) or failed implantation, and they had documented GH deficiency. These initial cycles were compared with their subsequent IVF cycles with GH supplementation. A non-parametric test was used for statistical analysis. RESULTS Embryo quality, determined by scoring the embryos on Day two using morphology, improved significantly after supplementation of GH (p-value is less than 0.001, median embryo score increased from 10.7 to 16). There was also a statistically significant increase in the fertilisation rate for those patients who had ICSI. There was no statistical difference in the number of oocytes retrieved or in the mean endometrial thickness with GH. CONCLUSION This study implies that GH supplementation may improve embryo quality in selected patients with GH deficiency. Its role in improving fertilisation rate at ICSI merits further research and evaluation.
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Zhu Z, Zhu M, Li H. Wound healing and application of rhEGF in 29 burn cases with TBSA over 90% included ¢ó degree over 50%. Burns 2007. [DOI: 10.1016/j.burns.2006.10.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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318
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Zhu Z, Zhu M, Li W. Preventing donor of split skin scarring with epidermal grafting in people of Asia. Burns 2007. [DOI: 10.1016/j.burns.2006.10.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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319
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Zhu M, Chen G, Chen D, Qi HG, Xia ZX, Wang SS, Huang YB, Zhang WJ, Chen ZK, Chen S. Induction of Accommodation Model by Combined RNA Interference Targeting 1,3-Galactosyltransferase Gene and Low-Dose GS-IB4 Lectin In Vitro. Transplant Proc 2006; 38:3193-5. [PMID: 17175219 DOI: 10.1016/j.transproceed.2006.10.135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVE This study sought to mimic the interaction of xenograft endothelial cells and human serum in vitro after successfully silencing the expression of porcine alpha1,3-galactosyltransferase (alpha1,3GT) gene by RNA interference (RNAi), and to investigate the possibility of inducing accommodation in vitro by stimulation of alpha-Gal-specific binding lectin, Griffonia simplicifolia isolectin B4 (GS-IB4) and RNAi. MATERIALS AND METHODS Various alpha-Gal expression patterns on a pig endothelial cell immortalized line (PED) was achieved by serial doses of small interfering RNA (siRNA) targeting porcinc alpha1,3GT gene. alpha1,3GT-siRNA transfected PEDs were exposed to increasing doses of GS-IB4 lectin (0.5, 2, and 8 microg/mL) for 4 hours before incubation with normal human serum (NHS). Accommodation phenomenon of PEDs in NHS was observed by 51Cr release and antibody/complement binding assays. RESULTS With combined RNAi and low-dose GS-IB4 stimulation, PEDs remarkably inhibited complement-mediated cytotoxicity, which showed a better protective effect than using RNAi alone. At a concentration of 2 mug/mL, GS-IB4 exhibited the maximum protective effect. The expression of E-selectin on alpha1,3GT-siRNA transfected PEDs did not differ from that on parental PEDs with heat-inactivated NHS (HINHS) stimulation. Combined with GS-IB4 stimulation, however, it inhibited expression of E-selectin, which was GS-IB4 dose dependent, resulting in mean fluorescence intensity values of 98.5, 42.0, and 36.3 at 0.5, 2, and 8 microg/mL. The mRNA expression of the protective gene HO-1 was significantly up-regulated after treatment with RNAi and low-dose of GS-IB4. CONCLUSIONS Combined RNAi and low-dose GS-IB4 induced pig endothelial cell accommodation in vitro. The level of alpha-Gal expression played an important role in the induction of accommodation.
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Zeng MH, Fang CY, Wang SS, Zhu M, Xie L, Li R, Wang L, Wu XW, Chen S. A Study of Soluble HLA-G1 Protecting Porcine Endothelial Cells Against Human Natural Killer Cell-Mediated Cytotoxicity. Transplant Proc 2006; 38:3312-4. [PMID: 17175258 DOI: 10.1016/j.transproceed.2006.10.179] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Indexed: 11/25/2022]
Abstract
UNLABELLED Human natural killer (NK) cells, which can mediate direct lysis of porcine endothelial cells, play an important role in xenograft rejection. HLA-G, which is a critical molecule in maintaining maternal immune tolerance of semi-allogenic fetus, is able to protect susceptible target cells from lysis induced by NK cells. In this study, we investigated whether soluble HLA-G1 (sHLA-G1) protected porcine xenogeneic cells against human NK cell-mediated lysis. METHODS The human sHLA-G1 genomic DNA (pcDNA3-sHLA-G1) was transfected into a B lymphoblastoid cell line 721.221 (LCL721.221) by nucleofector. The sHLA-G1 expression of the transfected LCL721.221 cells was identified by RT-PCR and Dot-ELISA. The sHLA-G1 protein was purified by affinity chromatography on anti-HLA-ImAb W6/32 coupled to cyanogen-bromide-activated Sepharose 4B from culture supernates of transfectants. Various concentrations of sHLA-G(1) protein (0, 2, 4, 6, or 8 microg/mL) were added to a NK cell-mediated xenogenic cell lysis system with either NK92 cells or fresh human peripheral blood mononuclear cells (PBMCs) cocultured with the porcine endothelial cells line. A LDH release assay was used to evaluate NK cell-mediated cytotoxicity. RESULTS sHLA-G1 provided significant protection of porcine endothelial cells against human NK-mediated cytotoxicity in a dose-dependent manner. The rates of NK92 cell-mediated cytotoxicity were reduced to 83.4 +/- 5.7% (2 microg/mL), 56.6 +/- 9.3% (4 microg/mL), 39.3 +/- 10.2% (6 microg/mL), and 31.2 +/- 4.9% (8 microg/mL) versus 96.9 +/- 3.0% in the control group (P < .01). Similarly, adding 6 microg/mL sHLA-G1 reduced the mean rate of PBMC-mediated cytotoxicity (n = 4) to 5.8 +/- 1.6% from 23.9 +/- 1.3% in the control group (P < .01). CONCLUSIONS These results indicated that sHLA-G1 protected xenogeneic porcine endothelial cells against attack by human NK cells, thus providing a new approach to overcome NK-mediated immunity to xenografts.
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Yin ZZ, Xie L, Zeng MH, Li R, Huang YB, Zhu M, Chen G, Chen S. Sertoli Cells Induce Xenolymphocyte Apoptosis In Vitro. Transplant Proc 2006; 38:3309-11. [PMID: 17175257 DOI: 10.1016/j.transproceed.2006.10.126] [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] [Received: 06/14/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND Testicular Sertoli cells can protect pancreatic islet grafts from allo- and autoimmune destruction; however, the mechanisms underlying immune privilege of the testicle are not well understood, especially in xenotransplantation. The purpose of this study was to investigate whether rat Sertoli cells could induce mouse lymphocyte apoptosis in vitro. METHODS Testis was isolated from 2- to 4-week-old Sprague Dawley (SD) rats. Sertoli cells were successfully prepared by digestion with collagenase type V, trypsin, and DNase I, and then identified by electron microscope. Viability and apoptosis of cultured cells were measured by flow cytometry. We examined the apoptosis rates of Balb/c mouse lymphocytes, which were cocultured with SD rat Sertoli cells by FACS. The expression of Fas ligand (Fasl), transforming growth factor (TGF)-beta1 and clusterin on Sertoli cells were detected by immunocytochemistry. RESULTS In the cocultured system, Sertoli cells accounted for more than 93%. With our isolation method, the viability of Sertoli cells was more than 95% and the apoptosis rate was 10.87% +/- 3.87%. The lymphocyte apoptosis ratio was 15.52 +/- 0.17 (P < .01, compared with the control groups). SABC immunochemistry staining showed that the sertoli cells could express FasL, TGF-beta, and clusterin. CONCLUSIONS In our coculture in vitro, rat Sertoli cells expressed FasL and TGF-beta1 as well as induced the apoptosis of mouse lymphocytes. These results indicated that the expression of FasL and TGF-beta1 on Sertoli cells might relate to immune privilege in xenotransplantation.
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Peloquin CA, Maslow JN, Mikota SK, Forrest A, Dunker F, Isaza R, Peddie LR, Peddie J, Zhu M. Dose selection and pharmacokinetics of rifampin in elephants for the treatment of tuberculosis. J Vet Pharmacol Ther 2006; 29:581-5. [PMID: 17083464 DOI: 10.1111/j.1365-2885.2006.00789.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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323
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Yan WH, Lin A, Chen XJ, Dai MZ, Gan LH, Zhou MY, Zhu M, Shi WW, Liu JM. Association of the maternal 14-bp insertion polymorphism in the HLA-G gene in women with recurrent spontaneous abortions. ACTA ACUST UNITED AC 2006; 68:521-3. [PMID: 17176444 DOI: 10.1111/j.1399-0039.2006.00723.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Human leukocyte antigen (HLA)-G has been postulated as an important immunotolerant molecule in maintaining fetal-maternal relationship. Recent reports indicated that the 14-bp deletion/insertion polymorphism in exon 8 of HLA-G gene influences HLA-G mRNA stability and isoform splicing patterns, thus modulating the levels of HLA-G expression. This might play an immunomodulatory role of HLA-G during implantation and pregnancy. In the present study, 109 unrelated fertile control women and 79 women who had experienced recurrent spontaneous abortion (RSA) were genotyped for the 14-bp insertion/deletion polymorphism. No significant difference was observed in the distribution of 14-bp insertion/deletion genotype between controls and the RSA group. However, a greater number of 14-bp insertion alleles exist in the RSA group than in the controls.
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Zhang X, Yang G, Liu Y, Yu W, Pan K, Li R, Zhu M. Induction of programmed cell death in aging Prorocentrum donghaiense cells as was evidenced preliminarily by the identification of associated transcripts. ACTA BIOLOGICA HUNGARICA 2006; 57:473-83. [PMID: 17278709 DOI: 10.1556/abiol.57.2006.4.9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Prorocentrum donghaiense caused large-scale red tides off Chinese coast in recent years. Expressed sequence tag (EST) analysis was carried out for this dinoflagellate in order to identify the genes involved in its proliferation and death. A cDNA library was constructed for P. donghaiense at late exponential growth phase, and 308 groups of EST were generated, which include 36 contigs and 272 singletons. Among 22 groups showed homologies with known genes, 2 matched significantly with caspase and proliferating cell nuclear antigen. Caspase and proliferating cell nuclear antigen are 2 key proteins involved in programmed cell death. Their identification evidenced preliminarily the induction of PCD in aging P. donghaiense. The identified included also calmodulin and protein phosphatase, two proteins involved in diverse cell processes including PCD by binding to or modifying others.
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Baril P, Gangeswaran R, Mahon PC, Caulee K, Kocher HM, Harada T, Zhu M, Kalthoff H, Crnogorac-Jurcevic T, Lemoine NR. Periostin promotes invasiveness and resistance of pancreatic cancer cells to hypoxia-induced cell death: role of the beta4 integrin and the PI3k pathway. Oncogene 2006; 26:2082-94. [PMID: 17043657 DOI: 10.1038/sj.onc.1210009] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pancreatic ductal adenocarcinoma is a devastating disease, characterized by a rapid progression and poor treatment response. Using gene expression profiling of pancreatic cancer tissues, we previously identified periostin as a potential diagnostic and therapeutic target. In this study, we report the overexpression of periostin in a larger set of pancreatic cancer tissues and show that although the periostin transcript is exclusively expressed in tumour cells, the protein product is only detected in the extracellular matrix adjacent to cancer cells. Using an enzyme-linked immunosorbent assay (ELISA) assay, we show significantly increased levels of periostin in the sera of pancreatic cancer patients compared to non-cancer controls. We demonstrate that periostin promotes the invasiveness of tumour cells by increasing the motility of cells without inducing expression of proteases, and enhances the survival of tumour cells exposed to hypoxic conditions. At the molecular level, we provide evidence that the alpha(6)beta(4) integrin complex acts as the cell receptor of periostin in pancreatic cancer cells and that interaction promotes phosphorylation of focal adhesion kinase (FAK) and protein kinase B (AKT) though activation of the PI3 kinase pathway, but not the RAS/MEK/ERK pathway. These findings suggest an important role of periostin in pancreatic cancer and provide a rationale to study periostin for diagnostic and therapeutic applications.
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