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Wang D, Zhao Y, Zhang Y, Zhang T, Shang X, Wang J, Liu Y, Kong Q, Sun B, Mu L, Liu X, Wang G, Li H. Hypothermia protects against oxygen-glucose deprivation-induced neuronal injury by down-regulating the reverse transport of glutamate by astrocytes as mediated by neurons. Neuroscience 2013; 237:130-8. [PMID: 23402854 DOI: 10.1016/j.neuroscience.2013.01.056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 01/25/2013] [Accepted: 01/27/2013] [Indexed: 11/29/2022]
Abstract
Glutamate is the major mediator of excitotoxic neuronal death following cerebral ischemia. Under severe ischemic conditions, glutamate transporters can functionally reverse to release glutamate, thereby inducing further neuronal injury. Hypothermia has been shown to protect neurons from brain ischemia. However, the mechanism(s) involved remain unclear. Therefore, the aim of this study was to investigate the mechanism(s) mediating glutamate release during brain ischemia-reperfusion injury under hypothermic conditions. Neuron/astrocyte co-cultures were exposed to oxygen-glucose deprivation (OGD) at various temperatures for 2h, and cell viability was assayed 12h after reoxygenation. PI and MAP-2 staining demonstrated that hypothermia significantly decreased neuronal injury. Furthermore, [(3)H]-glutamate uptake assays showed that hypothermia protected rat primary cortical cultures against OGD reoxygenation-induced injury. Protein levels of the astrocytic glutamate transporter, GLT-1, which is primarily responsible for the clearance of extracellular glutamate, were also found to be reduced in a temperature-dependent manner. In contrast, expression of GLT-1 in astrocyte-enriched cultures was found to significantly increase following the addition of neuron-conditioned medium maintained at 37 °C, and to a lesser extent with neuron-conditioned medium at 33 °C. In conclusion, the neuroprotective effects of hypothermia against brain ischemia-reperfusion injury involve down-regulation of astrocytic GLT-1, which mediates the reverse transport of glutamate. Moreover, this process may be regulated by molecules secreted by stressed neurons.
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Satoh D, Kawata S, Takahashi K, Izumiyama T, Barada D, Ma Y, Kong Q, Wang P, Wang W, Li Y, Sheng Z, Klimo O, Limpouch J, Andreev A. Laser-plasma booster for ion post acceleration. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20135917013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Kawata S, Takahashi K, Satoh D, Barada D, Ma Y, Kong Q, Wang P, Wang W, Li Y, Sheng Z, Klimo O, Limpouch J, Andreev A. Efficient ion generation in laser-foil interaction. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20135917012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Yang F, Wu W, Yan Y, Pang Y, Kong Q. Treatment with a neutralising anti-murine interleukin-17 antibody after the onset of coxsackievirus B3-induced viral myocarditis reduces myocardium inflammation. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Yang F, Wu WF, Yan YL, Pang Y, Kong Q. Expression of IL-23/Th17 Pathway in a Murine Model of Coxsackie Virus B3-Induced Viral Myocarditis. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Shen L, Xiao M, Kong F, Brown M, Sun J, Kong Q, Cha J, Xiang H, Xu H, Jin H, Wei L, Ni X. Detection of Laribacter hongkongensis using species-specific duplex PCR assays targeting the 16S rRNA gene and the 16S-23S rRNA intergenic spacer region (ISR). J Appl Microbiol 2011; 111:625-30. [PMID: 21689224 DOI: 10.1111/j.1365-2672.2011.05083.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS For the rapid detection of Laribacter hongkongensis, which is associated with human community-acquired gastroenteritis and traveller's diarrhoea, we developed a duplex species-specific PCR assay. METHODS AND RESULTS Full-length of the 16S-23S rRNA intergenic spacer region (ISR) sequences of 52 L. hongkongensis isolates were obtained by PCR-based sequencing. Two species-specific primer pairs targeting 16S rRNA gene and ISR were designed for duplex PCR detection of L. hongkongensis. The L. hongkongensis species-specific duplex PCR assay showed 100% specificity, and the minimum detectable level was 2.1 × 10(-2) ng μl(-1) genomic DNA which corresponds to 5000 CFU ml(-1). CONCLUSIONS The high specificity and sensitivity of the assay make it suitable for rapid detection of L. hongkongensis. SIGNIFICANCE AND IMPACT OF THE STUDY This species-specific duplex PCR method provides a rapid, simple, and reliable alternative to conventional methods to identify L. hongkongensis and may have applications in both clinical and environmental microbiology.
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Ni X, Sun J, Kong Q, Kong F, Brown M, Shen L, Cha J, Xiang H, Xu H, Jin H. Isolation of Laribacter hongkongensis from Little Egrets (Egretta garzetta) in Hangzhou, China. Lett Appl Microbiol 2011; 52:465-7. [DOI: 10.1111/j.1472-765x.2011.03024.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yang F, Wu W, Yan Y, Kong Q, Pang Y. e0220 The involvement of IL-23/Th17 pathway in murin model of coxsackie virus B3-induced viral myocarditis. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Yang F, Wu W, Yan Y, Kong Q, Pang Y. e0216 The expression and role of interleukin-23 in mice virus myocarditis. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Chen Y, Kong Q. Nuclear translocation of telomerase reverse transcriptase: a critical process in chemical induced hepatocellular carcinogenesis. Neoplasma 2010; 57:222-7. [PMID: 20353272 DOI: 10.4149/neo_2010_03_222] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Telomerase, a ribonuclearprotein complex, functions not only in cancer development but also in apoptosis, and senescence. As a catalytic subunit of telomerase, telomerase reverse transcriptase (TERT) has been confirmed to regulate telomerase activity in a rate-limiting manner. Although a lot of work has been done, the dynamic state of TERT protein and the relationship with telomerase have not been delineated systematically in cancer development. The purpose of this study was to do such an exploration. To investigate the role of TERT in the in vivo carcinogenesis, we performed immunofluorescence and Western blot analysis, respectively, to detect the alteration of TERT status as well as telomeric repeat amplification protocol (TRAP) assay to detect telomerase activity in diethyl nitrosoamine (DENA) induced rat hepatocellular carcinoma (HCC). The course of cancer development was divided into three main stages, which were inflammation ( <12 weeks), hepatocirrhosis (15 weeks), and hepatocarcinoma (18-21 weeks). In normal liver and its early inflammatory stage, concomitant with a weak positive TERT signal, which was detected exclusively in the cytoplasm, telomerase activity was very low at this stage. However, in late hepatocirrhosis and particularly cancer stage, high levels of TERT expression (P = 0.044 and P = 0.001, respectively) and telomerase activity (P = 0.02 and P = 0.01, respectively) were observed following TERT nuclear translocation. Our data suggest that TERT protein might regulate telomerase activity. TERT translocation from cytoplasm to the nucleus might be a turning point in cancer development. Therefore, TERT translocation might be more useful than TERT expression level and telomerase activity in predicting the progression of HCC.
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Kong Q, Qin C. Analysis of Current Laboratory Animal Science Policies and Administration in China. ILAR J 2010; 51:e1-e11. [DOI: 10.1093/ilar.51.1.e1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Chen Y, Kong Q. Evaluation of centrosome abnormalities and p53 inactivation in chemical induced hepatocellular carcinogenesis. Neoplasma 2009; 56:169-76. [PMID: 19239333 DOI: 10.4149/neo_2009_02_169] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
UNLABELLED Abnormal centrosome frequently found in human cancer is a major cause of mitotic defects and chromosome instability in cancer cells. Centrosome duplication is controlled in a cell cycle-specific manner, whereas cancer cells with dysregulation of centrosome duplication can survive and reenter the cell cycle through defective cell cycle checkpoint systems. Although numerous studies showed that centrosome amplification can be readily induced by loss or mutational inactivation of p53, however, the role of centrosomally localized p53 in the regulation of centrosome duplication had been enigma. To investigate the role of centrosome and p53 in the in vivo carcinogenesis, we performed immunofluorescence and Western blot analysis, respectively, to detect the alteration of centrosome and p53 status as well as immunohistochemical assay to detect cell proliferation in diethyl nitrosoamine (DENA) induced rat hepatocellular carcinoma (HCC). The frequencies of the centrosome abnormalities in HCC lesions were significantly higher than that of in their preneoplasitc counterparts as well as cell proliferation expression profile. Intriguingly, there was no correlation between centrosome abnormalities and cell proliferation. As for p53, the level of p53 increased in inflammation lesion, but decreased in hepatocirrhosis lesion, even undetectable in HCC lesion. These findings may imply that in inflammatory lesions aberration centrosome occurred irrespective of p53 background. However, the significantly increased percentage of cells with abnormal centrosome in hepatocirrhosis, particularly in HCC lesion concomitant with p53 inactivation and increased cell proliferation rate might synergistically contribute to carcinogenesis. Taken together, centrosome abnormalities were an early event prior to p53 inactivation in the time course of carcinogenesis, suggesting that p53 inactivation may not be the cause of centrosome aberration and centrosome may be a susceptible organelle responding to cellular insults. KEYWORDS centrosome, p53, hepatocellular carcinoma, cell proliferation.
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Chen Y, Deng W, Zhu H, Li J, Xu Y, Dai X, Jia C, Kong Q, Huang L, Liu Y, Ma C, Xiao C, Liu Y, Li Q, Bezard E, Qin C. The pathologic features of neurocutaneous melanosis in a cynomolgus macaque. Vet Pathol 2009; 46:773-5. [PMID: 19276048 DOI: 10.1354/vp.08-vp-0243-q-bc] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Neurocutaneous melanosis (NCM) is a rare phakomatosis characterized by proliferation of melanin-producing cells in both the skin and the brain. In this study, we describe the clinical and pathologic features of NCM in a 4.5-year-old female cynomolgus macaque. Histopathologically, skin lesions showed foci of nests and cords of pigmented cells in the dermis similar to blue nevi in humans. In the brain, focal pigmented cell infiltration was observed in the connective tissue under the leptomeninges and in the brain parenchyma. The pigmented cell was moderately reactive with a pan-melanoma antibody (melanoma(pan)) in the skin. In the brain, the pigmented cell was moderately to strongly positive for melanoma(pan) in subleptomeningeal areas and in the cerebral cortex. Melanosomes were observed in pigmented cells in the brain by electron microscopic examination. Based on the histologic, immunohistochemical, and electron microscopic results, the diagnosis of NCM was made. This case is possibly the first report of the condition in animals.
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Wang Q, Sun B, Wang D, Ji Y, Kong Q, Wang G, Wang J, Zhao W, Jin L, Li H. Murine bone marrow mesenchymal stem cells cause mature dendritic cells to promote T-cell tolerance. Scand J Immunol 2008; 68:607-15. [PMID: 18959624 DOI: 10.1111/j.1365-3083.2008.02180.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Bone mesenchymal stem cells (BMSC) are attractive not only in regenerative medicine, but also for the treatment of autoimmune diseases and graft-versus-host disease. BMSC also play a role in enabling alloantigen tolerance. An in-depth mechanistic understanding of this phenomenon of tolerance could lead to novel cell-based therapies for autoimmune disease. We demonstrate here that co-culture of mature dendritic cells (DC) with BMSC in a transwell system (BMSC-DC) downregulated expression of the maturation marker, CD83 and CD80/86 co-stimulatory molecules on DC, while increasing their endocytic activity. This resulted in defective antigen presentation and co-stimulatory capacity of mature DC. Functionally, BMSC-DC have impaired T-cell stimulatory activity in a mixed lymphocyte reaction and orchestrate a shift from predominantly pro-inflammatory T-helper (Th)-1 to anti-inflammatory Th2 cells. While the expression of MHC II, CD80 and CD86 were upregulated on BMSC co-cultured with DC, these BMSC lacked the ability to stimulate T-cell proliferation. Taken together, these data suggest that the interaction between BMSC and DC modulates the immunoregulatory function of these cells in a coordinated manner, effectively skewing the immune response towards T-cell tolerance.
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Jia R, Tai F, An S, Broders H, Ding X, Kong Q, Zhao L, Zhang H. Effects of neonatal oxytocin treatment on aggression and neural activities in mandarin voles. Physiol Behav 2008; 95:56-62. [DOI: 10.1016/j.physbeh.2008.04.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Revised: 04/04/2008] [Accepted: 04/09/2008] [Indexed: 11/25/2022]
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Nielsen M, Christensen M, Haldrup K, Harrit N, Feidenhans'l R, Kong Q, Cammarata M, Manuela L, Wulff M. Time-resolved X-ray scattering of an electronically excited state in metal complexes in solution. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308095494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Kong Q, Zhang X, Mo F, Li S, Ma M. Effect of particle size of lucerne hay on chewing
activity, digestion and energy balance of Chinese
Holstein heifers. JOURNAL OF ANIMAL AND FEED SCIENCES 2007. [DOI: 10.22358/jafs/74509/2007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Wang W, Wang PX, Ho YK, Kong Q, Gu Y, Wang SJ. Vacuum electron acceleration and bunch compression by a flat-top laser beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:093103. [PMID: 17902943 DOI: 10.1063/1.2780816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The field intensity distribution and phase velocity characteristics of a flat-top laser beam are analyzed and discussed. The dynamics of electron acceleration in this kind of beam are investigated using three-dimensional test particle simulations. Compared with the standard (i.e., TEM(00) mode) Gaussian beam, a flat-top laser beam has a stronger longitudinal electric field and a larger diffraction angle. These characteristics make it easier for electrons to be trapped and accelerated by the beam. With a flat-top shape, the laser beam is also applicable to the acceleration of low energy electron and bunch compression.
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Zhang A, Kong Q, Cao L, Chen X. Effect of FPS1 deletion on the fermentation properties of Saccharomyces cerevisiae. Lett Appl Microbiol 2007; 44:212-7. [PMID: 17257263 DOI: 10.1111/j.1472-765x.2006.02041.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS To investigate the effect of FPS1 deletion on the fermentation properties of Saccharomyces cerevisiae and to evaluate whether FPS1 deletion would result in higher ethanol yield. METHODS AND RESULTS FPS1 of S. cerevisiae was knocked out using the one-step gene replacement method. The fermentation properties of the fps1Delta mutant under microaerobic conditions were investigated and compared with that of the wild type. Consumption of glucose, yield of ethanol, yield of glycerol, acetic acid and pyruvic acid were monitored. Compared with the wild type, the ethanol yield of the fps1Delta mutant was improved by 10 +/- 2% and glycerol yield decreased by 18.8 +/- 2%. Meanwhile, acetic acid yield decreased by 5.4 +/- 1%, and pyruvic acid yield decreased by 58.6 +/- 1%. CONCLUSIONS FPS1 deletion of S. cerevisiae resulted in reduced glycerol yield and higher ethanol yield. SIGNIFICANCE AND IMPACT OF THE STUDY The cost of carbon source in ethanol fermentation is an important factor in determining ethanol production. Approximately 5% carbon source is converted into glycerol in ethanol fermentation. Eliminating formation of glycerol through FPS1 deletion can be used to increase ethanol yield of S. cerevisiae without increasing the overall cost of carbon source.
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Kong Q, He GQ, Chen F, Ruan H. Studies on a kinetic model for butyric acid bioproduction by Clostridium butyricum. Lett Appl Microbiol 2006; 43:71-7. [PMID: 16834724 DOI: 10.1111/j.1472-765x.2006.01902.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AIMS This paper discusses the establishment of a kinetic model for cell growth, butyric acid production and substrate consumption of Clostridium butyricum ZJUCB in batch cultivation. METHODS AND RESULTS Mathematic simulations were proposed by the logistic equation for the cell growth, the Luedeking-Piret equation for butyric acid production and the Luedeking-Piret-like equation for glucose consumption. CONCLUSION We compared the performance of our model against that obtained by the empirically experimental design. The experiment-validated model was found suitable for studying butyric acid fermentation kinetics in a complex dynamic behaviour of C. butyricum, especially for its singular growth phenomenon. SIGNIFICANCE AND IMPACT OF THE STUDY The model parameters are estimated from the data fitting and evaluated for simulation of the time courses of the concentrations of cell biomass, butyric acid and glucose and the model appears to fit the experimental data well. The results may be useful for butyric acid production by microbial fermentation.
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Yao Y, Sun S, Kong Q, Tong E. 7beta-hydroxycholesterol reduces the extent of reactive gliosis caused by iron deposition in the hippocampus but does not attenuate the iron-induced seizures in rats. Neuroscience 2006; 138:1097-103. [PMID: 16442740 DOI: 10.1016/j.neuroscience.2005.12.011] [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: 08/11/2005] [Revised: 11/28/2005] [Accepted: 12/07/2005] [Indexed: 11/22/2022]
Abstract
7beta-Hydroxycholesterol has been previously demonstrated to inhibit astrocytosis in injured cortex or spinal cord of rats. In this study, we explored the inhibitory effects of the liposome containing 7beta-hydroxycholesterol on the reactive astrocytosis caused by the injection of iron into the hippocampus of rats and furthermore evaluated the involvement of reactive astrocytosis in iron-induced epilepsy. Injection of ferric chloride solution unilaterally into the hippocampus of rats induced spontaneous spiking activity ipsilaterally then developed into bilateral hippocampi and generalized convulsive seizures within the first week post-operation, and spontaneous epileptiform activity and generalized seizures lasted as long as 2 weeks post-operation, whereas none of the rats injected with sodium chloride solution unilaterally into the hippocampus developed generalized seizures. With immunohistochemistry and Western blot analyses, apparent reactive astrocytosis in bilateral hippocampi was detected using antibody against glial fibrillary acidic protein 14 days after the injection of ferric chloride solution, but no significant differences were found in the amount of synaptophysin protein, a presynaptic vesicle protein, as compared with the rats injected with sodium chloride solution. Infusion of liposome suspension containing 7beta-hydroxycholesterol into the same site immediately after the injection of ferric chloride solution reduced the extent of the reactive astrocytosis by 50%-55% of the amount of glial fibrillary acidic protein in the hippocampi of both hemispheres, and non-significantly elevated the amount of synaptophysin protein in both sides of hippocampus. However, these effects did not significantly modify the seizure latency and the incidence of generalized seizures in the rats. These findings demonstrate the effects of 7beta-hydroxycholesterol on the inhibition of reactive astrocytosis caused by iron deposition in the hippocampus of rats, and suggest that the reactive astrocytosis may not play a causal role in the development of iron-induced seizures.
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Weisman GA, Wang M, Kong Q, Chorna NE, Neary JT, Sun GY, González FA, Seye CI, Erb L. Molecular determinants of P2Y2 nucleotide receptor function: implications for proliferative and inflammatory pathways in astrocytes. Mol Neurobiol 2006; 31:169-83. [PMID: 15953819 DOI: 10.1385/mn:31:1-3:169] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Accepted: 11/15/2004] [Indexed: 01/05/2023]
Abstract
In the mammalian nervous system, P2 nucleotide receptors mediate neurotransmission, release of proinflammatory cytokines, and reactive astrogliosis. Extracellular nucleotides activate multiple P2 receptors in neurons and glial cells, including G protein-coupled P2Y receptors and P2X receptors, which are ligand-gated ion channels. In glial cells, the P2Y2 receptor subtype, distinguished by its ability to be equipotently activated by ATP and UTP, is coupled to pro-inflammatory signaling pathways. In situ hybridization studies with rodent brain slices indicate that P2Y2 receptors are expressed primarily in the hippocampus and cerebellum. Astrocytes express several P2 receptor subtypes, including P2Y2 receptors whose activation stimulates cell proliferation and migration. P2Y2 receptors, via an RGD (Arg-Gly-Asp) motif in their first extracellular loop, bind to alphavbeta3/beta5 integrins, whereupon P2Y2 receptor activation stimulates integrin signaling pathways that regulate cytoskeletal reorganization and cell motility. The C-terminus of the P2Y2 receptor contains two Src-homology-3 (SH3)-binding domains that upon receptor activation, promote association with Src and transactivation of growth factor receptors. Together, our results indicate that P2Y2 receptors complex with both integrins and growth factor receptors to activate multiple signaling pathways. Thus, P2Y2 receptors present novel targets to control reactive astrogliosis in neurodegenerative diseases.
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Wulff M, Bratos S, Plech A, Vuilleumier R, Mirloup F, Lorenc M, Kong Q, Ihee H. Recombination of photodissociated iodine: A time-resolved x-ray-diffraction study. J Chem Phys 2006; 124:034501. [PMID: 16438591 DOI: 10.1063/1.2149852] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A time-resolved x-ray-diffraction experiment is presented that aims to study the recombination of laser-dissociated iodine molecules dissolved in CCl4. This process is monitored over an extended time interval from pico- to microseconds. The variations of atom-atom distances are probed with a milliangstrom resolution. A recent theory of time-resolved x-ray diffraction is used to analyze the experimental data; it employs the correlation function approach of statistical mechanics. The most striking outcome of this study is the experimental determination of time-dependent I-I atom-atom distribution functions. The structure of the CCl4 solvent changes simultaneously; the solvent thus appears as a reaction partner rather than an inert medium hosting it. Thermal expansion of the system is nonuniform in time, an effect due to the presence of the acoustic horizon. One concludes that a time-resolved x-ray diffraction permits real-time visualization of solvent and solute motions during a chemical reaction.
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Wang XW, Li J, Guo T, Zhen B, Kong Q, Yi B, Li Z, Song N, Jin M, Xiao W, Zhu X, Gu C, Yin J, Wei W, Yao W, Liu C, Li J, Ou G, Wang M, Fang T, Wang G, Qiu Y, Wu H, Chao F, Li J. Concentration and detection of SARS coronavirus in sewage from Xiao Tang Shan Hospital and the 309th Hospital of the Chinese People's Liberation Army. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2005; 52:213-221. [PMID: 16312970 DOI: 10.2166/wst.2005.0266] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A worldwide outbreak of severe acute respiratory syndrome (SARS) had been reported. Over 8439 SARS cases and 812 SARS-related deaths were reported to the World Health Organization from 32 countries around the world up to 5 July 2003. The mechanism of transmission of SARS-CoV has been limited only to close contacts with patients. Attention was focused on possible transmission by the sewage system because laboratory studies showed that patients excreted coronavirus RNA in their stools in Amoy Gardens in Hong Kong. To explore whether the stool of SARS patients or the sewage containing the stool of patients would transmit SARS-CoV or not, we used a style of electropositive filter media particle to concentrate the SARS-CoV from the sewage of two hospitals receiving SARS patients in Beijing, as well as cell culture, semi-nested RT-PCR and sequencing of genes to detect and identify the viruses from sewage. There was no live SARS-CoV detected in the sewage in these assays. The nucleic acid of SARS-CoV was found in the sewage before disinfection from both hospitals by PCR. After disinfection, SARS-CoV RNA could be detected from some samples from the 309th Hospital of the Chinese People's Liberation Army, but not from Xiao Tang Shan Hospital after disinfection. In this study, we found that the virus can survive for 14 days in sewage at 4 degrees C, 2 days at 20 degrees C, and its RNA can be detected for 8 days though the virus had been inactivated. In conclusion, this study demonstrates that the RNA of SARS-CoV could be detected from the concentrates of sewage of both hospitals receiving SARS patients before disinfection and occasionally after disinfection though there was no live SARS-CoV; thus much attention should be paid to the treatment of stools of patients and the sewage of hospitals receiving SARS patients.
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He GQ, Kong Q, Ding LX. Response surface methodology for optimizing the fermentation medium of Clostridium butyricum. Lett Appl Microbiol 2004; 39:363-8. [PMID: 15355540 DOI: 10.1111/j.1472-765x.2004.01595.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS Strains of Clostridium butyricum have been increasingly used as probiotics for both animals and humans. The aim of this study was to develop a growth medium for cultivating C. butyricum ZJUCB using a statistical methodology. METHODS AND RESULTS Response surface methodology (RSM) was used to evaluate the effects of variables, namely the concentrations of the glucose, pectin, soyabean cake extract, casein, corn steep flour, ammonium sulphate, sodium bicarbonate and the medium initial pH. A fractional factorial design was applied to study the main factors that affected the growth of a probiotic strain of C. butyricum currently preserved in our lab and the central composite experimental design was adopted to derive a statistical model for optimizing the composition of the fermentation medium. The experimental results showed that the optimum fermentation medium for the growth of C. butyricum was composed of 2% glucose (w/v), 0.5% pectin (w/v), 0.2% casein (w/v), 3.98% soyabean cake extract, 0.1% (NH4)2SO4 (w/v), 0.124% NaHCO3 (w/v), 0.37% corn steep flour (w/v), 0.02% MnSO4 H2O (w/v), 0.02% MgSO4 7H2O (w/v) and 0.002% CaCl2 (w/v) at pH 7.5. CONCLUSIONS After incubating 24 h in the optimum fermentation medium, the populations of the viable organisms were estimated to be 10(9) CFU ml(-1). In the present study, we report the optimization of a growth medium that produced increased yields using statistical approach. SIGNIFICANCE AND IMPACT OF THE STUDY The use of bacteria as a probiotic is showing increasing potential. The development of a growth medium that has a high yield is an obvious need, and the approach to optimizing a growth medium is innovative.
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