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Krishnamurthy VMR, Terry C, Greene T, Sharma M, Zitterkoph J, Baird B, Wei G, Cheung A, Beddhu S. 152 Ergocalciferol (ERGO) Therapy in Calcidiol-Deficient Hemodialysis (HD) Patients on Therapeutic Doses of Paricalcitol. Am J Kidney Dis 2011. [DOI: 10.1053/j.ajkd.2011.02.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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77
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Dadi N, Wei G, Unruh M, Greene T, Baird B, Beddhu S. 74 Sleep Apnea (SA) is an Effect Modifier of Associations of Diabetes Mellitus (DM) on Albuminuria and Cardiovascular Disease (CVD): NHANES. Am J Kidney Dis 2011. [DOI: 10.1053/j.ajkd.2011.02.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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78
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Raukas M, Wei G, Bergenek K, Kelso J, Zink N, Zheng Y, Hannah M, Stough M, Wirth R, Linkov A, Jermann F, Eisert D. Luminescent ceramics for LED conversion. ACTA ACUST UNITED AC 2011. [DOI: 10.1117/12.875487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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79
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Yupeng W, Ming X, Wei G. e0027 Growth differentiation factor 15 induce the proliferation of cardiac fibroblasts in a dose dependent manner. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.27] [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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80
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Ying X, Yuan Z, Shuwang L, Wei G. e0558 Effects of right ventricular apical pacing on cardiopulmonary function in patients with normal heart functions. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.558] [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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81
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Wei G, Xue-Feng L, Yan Y, Ying-Yuan W, Ling-Li D, Li-Ping Z, Wen-Hua X, Jian-Hua Z. Equine influenza viruses isolated during outbreaks in China in 2007 and 2008. Vet Rec 2010; 167:382-3. [PMID: 20817902 DOI: 10.1136/vr.c3805] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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82
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Wang Y, Yao M, Zhou C, Dong D, Jiang Y, Wei G, Cui X. Erythropoietin promotes spinal cord-derived neural progenitor cell proliferation by regulating cell cycle. Neuroscience 2010; 167:750-7. [PMID: 20167254 DOI: 10.1016/j.neuroscience.2010.02.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 02/04/2010] [Accepted: 02/04/2010] [Indexed: 02/02/2023]
Abstract
Erythropoietin (EPO) regulates the proliferation and differentiation of erythroid cells by binding to its specific transmembrane receptor (EPOR). The presence of EPO and its receptor in the CNS suggests a different function for EPO other than erythropoiesis. The purpose of the present study was to examine EPOR expression and the role of EPO in the proliferation of neonatal spinal cord-derived neural progenitor cells. The effect of EPO on cell cycle progression was also examined, as well as the signaling cascades involved in this process. Our results showed that EPOR was present in the neural progenitor cells and EPO significantly enhanced their proliferation. Cell cycle analysis of EPO-treated neural progenitor cells indicated a reduced percentage of cells in G0/G1 phase, whereas the cell proliferation index (S phase plus G2/M phase) was increased. EPO also increased the proportion of 5-bromo-2-deoxyuridine (BrdU)-positive cells. With respect to the cell cycle signaling, we examined the cyclin-dependent kinases D1, D2 and E, and cyclin-dependent kinase inhibitors, p21cip1, p27kip1 and p57kip2. No significant differences were observed in the expression of these transcripts after EPO administration. Interestingly, the anti-apoptotic factors, mcl-1 and bcl-2 were significantly increased twofold. Moreover, these specific effects of EPO were eliminated by incubation of the progenitor cells with anti-EPO neutralizing antibody. Those observations suggested that EPO may play a role in normal spinal cord development by regulating cell proliferation and apoptosis.
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83
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Wei G, Doré S. Importance of normothermia control in investigating delayed neuronal injury in a mouse global ischemia model. J Neurosci Methods 2009; 185:230-5. [PMID: 19815029 DOI: 10.1016/j.jneumeth.2009.09.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 09/28/2009] [Accepted: 09/28/2009] [Indexed: 01/08/2023]
Abstract
This study aims to establish a mouse global cerebral ischemia model in which the physiological parameter measurements and neuronal injury evaluations are conducted in the same group of animals and to identify the effect of post-ischemic core temperature (CT) on the outcome of neuronal injury. Global ischemia was induced by 12-min bilateral common carotid artery occlusion followed by 7 days of reperfusion in C57BL/6 mice. Immediately after occlusion, mice were randomly assigned to be kept in environments of different temperatures [25 degrees C (room temperature, group 1), 33-34 degrees C for 2h (group 2), and 33-34 degrees C for 24h (group 3)] before being returned to their home cages. We found that in group 1, CT declined to approximately 32 degrees C after ischemia and then recovered at 24h post-ischemia; in group 2, CT remained at the pre-ischemia level during the first 2h, declined after the mice were returned to room temperature, and recovered at 24h post-ischemia; and in group 3, CT remained constant at the pre-ischemia level throughout the reperfusion period. The number of surviving neurons in a sector of the hippocampal CA1 region was significantly lower in all ischemic groups than in the sham controls, but the number was significantly higher in group 1 than that in groups 2 or 3 (P<0.05). We observed that CT declines initially but recovers spontaneously at 24h post-ischemia. Early post-ischemic hypothermia impacts the delayed neuronal injury, suggesting that tight temperature control immediately following ischemia is important to obtain the most reproducible neuronal damage in mouse models of cerebral global ischemia.
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84
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Dong D, Song L, Wei G. Optimization of HVAC Control to Improve Comfort and Energy Performance in a School. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/01998590809509375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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85
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Wei G, Xin J, Yang D, Liu X, Tai Y, Zhang H, Liang F, Zhang G. A New Modular Stent Graft to Reconstruct Aortic Arch. Eur J Vasc Endovasc Surg 2009; 37:560-5. [DOI: 10.1016/j.ejvs.2009.01.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Accepted: 01/24/2009] [Indexed: 10/21/2022]
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86
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Wu D, Hu R, Wei G. [Survey and treatment of clonorchiasis in Fushan city]. ZHONGGUO JI SHENG CHONG XUE YU JI SHENG CHONG BING ZA ZHI = CHINESE JOURNAL OF PARASITOLOGY & PARASITIC DISEASES 2009; 17:316. [PMID: 12563871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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87
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Liu N, Yu J, Li M, Huo Z, Ma L, Shi F, Wei G, Yang G. Assessment of Bone Metastasis: Initial Experience with 18F-FDG PET/CT and Comparison between 18F-FDG PET and Bone Scan. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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88
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Shi F, Yu J, Shi X, Kong L, Wei G, Li M, Li W. A Comparative Study on Radiology and Pathology Target Volume in Primary Liver Cancer. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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89
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Wei G, Kibler KK, Koehler RC, Maruyama T, Narumiya S, Doré S. Prostacyclin receptor deletion aggravates hippocampal neuronal loss after bilateral common carotid artery occlusion in mouse. Neuroscience 2008; 156:1111-7. [PMID: 18790018 DOI: 10.1016/j.neuroscience.2008.07.073] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 07/11/2008] [Accepted: 07/18/2008] [Indexed: 11/20/2022]
Abstract
Transient global cerebral ischemia causes delayed neuronal death in the hippocampal CA1 region. It also induces an increase in cyclooxygenase 2 (COX-2), which generates several metabolites of arachidonic acid, known as prostanoids, including prostacyclin (PGI(2)). To determine the role of the PGI(2) receptor (IP) in post-ischemic delayed cell death, wild-type and IP knockout (IP(-/-)) C57Bl/6 mice were subjected to 12-min bilateral common carotid artery occlusion or sham surgery, followed by 7 days of reperfusion. In the sham-operated mice, no statistical difference in CA1 hippocampal neuronal density was observed between the wild-type (2836+/-18/mm(2)) and IP(-/-) (2793+/-43/mm(2)) mice. Interestingly, in animals subjected to ischemia, surviving neuronal density in wild-type mice decreased to 50.5+/-7.9% and that of IP(-/-) mice decreased to 23.0+/-4.5% of their respective sham-operated controls (P<0.05). The results establish a role for the IP receptor in protecting pyramidal hippocampal neurons after this global ischemic model and suggest that IP receptor agonists could be developed to prevent delayed pyramidal neuronal cell death.
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90
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Gao L, Qian S, Zeng L, Wang R, Wei G, Fan J, Zheng S. An animal model of human cytomegalovirus infection. Transplant Proc 2008; 39:3438-43. [PMID: 18089401 DOI: 10.1016/j.transproceed.2007.06.077] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 03/31/2007] [Accepted: 06/21/2007] [Indexed: 11/16/2022]
Abstract
To develop a rat model that allowed in vivo progressive human cytomegalovirus (HCMV) infection, allogeneic liver transplantation was performed across a rat combination of Dark Agouti (DA) to Brown Norway (BN). AD169, a well-characterized laboratory strain of HCMV, was used to establish a rat model of HCMV infection by injection of 0.4 mL (30.0 logTCID50) supernate into the rat peritoneum. Histological and blood specimens were obtained from animals sacrificed at predetermined timepoints. We performed immunohistochemical staining in liver, heart, kidney, spleen, and lung for HCMV immediate-early antigen (IE), lower matrix protein (pp65) detection in peripheral blood leukocytes, and HCMV early antigen (EA) and late antigen (LA). We compared survival rates. Our results showed positive HCMV IE and pp65 antigenemia detected in peripheral blood leukocytes in transplanted recipients from day 1 to day 30. Positive HCMV EA and LA staining cells were only detected in sections 10 days after liver transplantation, namely, in hepatocytes, mononuclear cells, bile duct epithelial cells, and endothelial cells. Successful HCMV replication was due to the combination of liver transplantation and cyclosporine (CsA) immunosuppression. Survival analysis showed no significant differences between the HCMV-infected group and HCMV-uninfected group. This new rat model of HCMV infection may be helpful to understand immune system modulation of HCMV infection.
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91
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Mahowald AP, Wei G. Sex determination of germ cells in Drosophila. CIBA FOUNDATION SYMPOSIUM 2007; 182:193-202; discussion 202-9. [PMID: 7835150 DOI: 10.1002/9780470514573.ch11] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Many lines of evidence indicate that in Drosophila the mechanism for establishing the sex of the female germline is different from that acting in somatic cells. In the soma Sxl has an embryonic determinative role and is required throughout the life of female flies; in germ cells its expression begins only in the larval ovary. Both the mechanism for activating Sxl and the genes controlled by Sxl are different in the germline. A number of genes have been identified that are essential either for survival (e.g. ovo, otu) or differentiation (snf, Sxl, fl(2)d, bgcn) of female germ cells. ovo is required during embryogenesis for survival of pole cells. Genetic interactions with dominant alleles of ovo and/or Sxl indicate that otu, Sxl, snf and fl(2)d act in the same pathway as does ovo. bgcn differs in that neither ovo nor SxlD mutations affect the bgcn phenotype even though XX bgcn germ cells enter the male pathway. bgcn causes sterility in both sexes. Although the germline defect is cell autonomous in mosaic gonads, bgcn is also required in the somatic tissue for maintaining oogenesis of wild-type germ cells. Several dominant suppressors of bgcn have been identified and some have properties similar to Suppressors of variegation, suggesting that chromatin structure is critical for proper germ cell sex determination.
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92
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Wei G, Bergquist A, Broomé U, Lindgren S, Wallerstedt S, Almer S, Sangfelt P, Danielsson A, Sandberg-Gertzén H, Lööf L, Prytz H, Björnsson E. Acute liver failure in Sweden: etiology and outcome. J Intern Med 2007; 262:393-401. [PMID: 17697161 DOI: 10.1111/j.1365-2796.2007.01818.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To determine the causes and outcome of all patients with acute liver failure (ALF) in Sweden 1994-2003 and study the diagnostic accuracy of King's College Hospital (KCH) criteria and the model for end-stage liver disease (MELD) score with transplant-free deaths as a positive outcome. RESEARCH DESIGN AND METHODS Adult patients in Sweden with international normalized ratio (INR) of >or=1.5 due to severe liver injury with and without encephalopathy at admission between 1994-2003 were included. RESULTS A total of 279 patients were identified. The most common cause of ALF were acetaminophen toxicity in 42% and other drugs in 15%. In 31 cases (11%) no definite etiology could be established. The KCH criteria had a positive-predictive value (PPV) of 67%, negative-predictive value (NPV) of 84% in the acetaminophen group. Positive-predictive value and negative-predictive value of KCH criteria in the nonacetaminophen group were 54% and 63% respectively. MELD score>30 had a positive-predictive value of 21%, negative-predictive value of 94% in the acetaminophen group. The corresponding figures for the nonacetaminophen group were 64% and 76% respectively. CONCLUSIONS Acetaminophen toxicity was the most common cause in unselected patients with ALF in Sweden. KCH criteria had a high NPV in the acetaminophen group, and in combination with MELD score<30 predicts a good prognosis in acetaminophen patients without transplantation.
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93
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Li K, Guan W, Wei G, Liu B, Xu J, Zhao L, Zhang Y. Phylogenetic analysis of intestinal bacteria in the Chinese mitten crab (Eriocheir sinensis). J Appl Microbiol 2007; 103:675-82. [PMID: 17714401 DOI: 10.1111/j.1365-2672.2007.03295.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS To identify the dominant intestinal bacteria in the Chinese mitten crab, and to investigate the differences in the intestinal bacteria between pond-raised and wild crabs. METHODS AND RESULTS The diversity of intestinal bacteria in the Chinese mitten crabs was investigated by denaturing gradient gel electrophoresis (DGGE) fingerprinting, 16S rRNA gene clone library analysis and real-time quantitative PCR. The principal component analysis of DGGE profiles indicated that substantial intersubject variations existed in intestinal bacteria in pond-raised crab. The sequencing of 16S rRNA genes revealed that 90-95% of the phylotypes in the clone libraries were affiliated with Proteobacteria and Bacteroidetes. Some genera were identified as unique in wild crabs and in pond-raised crabs, whereas Bacteroidetes was found to be common in all sampled crab groups. Real-time quantitative PCR indicated that the abundance of Bacteroides and the total bacterial load were approximately four-to-10 times higher in pond-raised crabs than in wild crabs. A significant portion of the phylotypes shared low similarity with previously sequenced organisms, indicating that the bacteria in the gut of Chinese mitten crabs are yet to be described. CONCLUSIONS The intestinal bacteria of pond-raised crabs showed higher intersubject variation, total diversity and abundance than that observed in wild crabs. The high proportion of the clones of Proteobacteria and Bacteroidetes in the clone library is an indication that these bacteria may be the dominant population in the gut of the Chinese mitten crab. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrated obvious differences in the intestinal bacterial composition of pond-raised crabs and wild crabs. This knowledge will increase our understanding of the effects of aquaculture operations on bacterial community composition in the crab gut and provide necessary data for the development of probiotic products for crab cultivation.
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94
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Yan L, Na W, Shan K, Xiao-Wei M, Wei G, Shu-Cheng C. p16(CDKN2) gene polymorphism: association with histologic subtypes of epithelial ovarian cancer in China. Int J Gynecol Cancer 2007; 18:30-5. [PMID: 17466040 DOI: 10.1111/j.1525-1438.2007.00953.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
p16 is an important tumor suppressor gene, which is inactivated in many kinds of tumors. The common variants of p16 may be associated with the risk of certain tumors development. We analyzed the frequency of two adjacent polymorphisms in p16 exon 3 (540C-->G and 580C-->T) and their haplotype in blood samples from epithelial ovarian cancer (EOC) patients and healthy controls using polymerase chain reaction-restriction fragment length polymorphism. The results showed that the genotype frequency of p16 580C-->T polymorphism was significantly different among histologic subtypes of EOC (P= 0.02). T allele carriers significantly reduced the risk of serous EOC; the adjusted odds ratio was 0.40 (95% CI = 0.19-0.84). There are neither association between p16 540C-->G polymorphism and EOC development, progression, nor association between the haplotypes of two single nucleotide polymorphisms and the tumor development. Our results suggested that the p16 580C-->T polymorphism might affect the individual susceptibility to specific subtypes of EOC. Different types of ovarian cancer might adopt distinct carcinogenetic pathways. However, this result may be further validated in a larger sample of patients.
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MESH Headings
- 3' Untranslated Regions/genetics
- Adenocarcinoma, Mucinous/genetics
- Adenocarcinoma, Mucinous/metabolism
- Adenocarcinoma, Mucinous/pathology
- Adult
- Aged
- Carcinoma, Endometrioid/genetics
- Carcinoma, Endometrioid/metabolism
- Carcinoma, Endometrioid/pathology
- Case-Control Studies
- China
- Cyclin-Dependent Kinase Inhibitor p16/genetics
- Cystadenocarcinoma, Serous/genetics
- Cystadenocarcinoma, Serous/metabolism
- Cystadenocarcinoma, Serous/pathology
- Disease Progression
- Female
- Genetic Predisposition to Disease
- Genotype
- Haplotypes/genetics
- Humans
- Middle Aged
- Ovarian Neoplasms/genetics
- Ovarian Neoplasms/metabolism
- Ovarian Neoplasms/pathology
- Polymerase Chain Reaction
- Polymorphism, Single Nucleotide/genetics
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95
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Fountaine RJ, Nishizawa Y, Wei G, Dogolo L, Calcagni A, Gardner MJ. Clinical pharmacology of lasofoxifene in Japanese and white postmenopausal women. J Clin Pharmacol 2006; 46:693-9. [PMID: 16707415 DOI: 10.1177/0091270006288213] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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96
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Wei G. Nerve Agent Antidote Kits Enable Nurses to Treat More Mass-casualty Patients Than Multidose Vials. Acad Emerg Med 2006. [DOI: 10.1197/j.aem.2006.03.447] [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]
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97
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Liu Z, Li Z, Zhou H, Wei G, Song Y, Wang L. Immobilization and condensation of DNA with 3-aminopropyltriethoxysilane studied by atomic force microscopy. J Microsc 2005; 218:233-9. [PMID: 15958016 DOI: 10.1111/j.1365-2818.2005.01482.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We used different methods to modify a mica surface with 3-aminopropyltriethoxysilane (APTES), and then used it as substrate to immobilize DNA for atomic force microscopy (AFM) observation. The evaporation method and solution modifying method were investigated and evaluated. The solution modifying method was found to be relatively simple and effective. Using an APTES solution-modified mica surface, DNA immobilization appeared more reproducible and it could be imaged in liquid. The mixed solution of APTES and DNA was dropped directly onto the mica surface for AFM imaging. We found that DNA can condense in APTES water solutions. Toroids, rods and intermediate structures of condensation were captured by AFM.
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98
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Nie W, Wei G, Du G, Li Y, Chen J. Enhanced intracellular glutathione synthesis and excretion capability of Candida utilis by using a low pH-stress strategy. Lett Appl Microbiol 2005; 40:378-84. [PMID: 15836743 DOI: 10.1111/j.1472-765x.2005.01687.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To study the effect of low pH stress on glutathione (GSH) synthesis and excretion capability of GSH fermentation production in Candida utilis. METHODS AND RESULTS When C. utilis WSH 02-08 was cultivated in a glucose-ammonium sulfate medium without pH control, GSH leakage occurred when the pH of the medium decreased to 1.5. However, analysis of the cell viability indicated that the cells were not lysed. To further study the effect of low pH stress on GSH production, pH-controlled batch cultures were conducted, where the pH was switched from 5.5 to 1.2 at 24 h and maintained at 1.2 for 6 h. Nearly all intracellular GSH was leaked into the medium and the cell viability decreased dramatically, conceiving a long-term exposure of strain WSH 02-08 at low pH environment led to a complete cell lysis. A critical point (treated at pH 1.2 for 3 h) was experimentally determined, where most cells were alive but suffering a low pH stress. Low pH-stressed C. utilis cells displayed an increased intracellular GSH synthesis and export capability, which protected the cells against short-term low pH treatment. CONCLUSIONS Using this knowledge, a low pH-stress strategy was developed and applied in fed-batch production of GSH and 197.3 mg l-1 of GSH was secreted into the medium. The GSH-specific production yield could be increased from 2.11 to 2.67% (w/w), and the total GSH concentration could reach 737.1 mg l-1 and increased by 24.9%. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report of GSH secretion of C. utilis at low pH. This study demonstrated the importance of the physiology-based fermentation strategy in the production of useful metabolites.
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99
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Wei G, Hough CJ, Li Y, Sarvey JM. Characterization of extracellular accumulation of Zn2+ during ischemia and reperfusion of hippocampus slices in rat. Neuroscience 2004; 125:867-77. [PMID: 15120848 DOI: 10.1016/j.neuroscience.2004.03.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2004] [Indexed: 11/20/2022]
Abstract
The mammalian CNS contains an abundance of chelatable zinc that is sequestered in the vesicles of glutamatergic presynaptic terminals and co-released with glutamate. Considerable Zn(2+) is also released during cerebral ischemia and reperfusion (I/R) although the mechanism of this release has not been elucidated. We report here the real time observation of increase of the concentration of extracellular Zn(2+) ([Zn(2+)](o)), accompanied by a rapid increase of intracellular free Zn(2+)concentration, in the areas of dentate gyrus (DG), CA1 and CA3 in acute rat hippocampus slices during ischemia simulated by deprivation of oxygen and glucose (OGD) followed by reperfusion with normal artificial cerebrospinal fluid. A brief period of OGD caused a sustained increase of [Zn(2+)](o). Subsequent reperfusion with oxygenated medium containing glucose resulted in a further increase of [Zn(2+)](o). Longer periods of OGD caused greater increases of [Zn(2+)](o,) and subsequent reperfusion caused still further increases of [Zn(2+)](o,) regardless of OGD duration. The Zn(2+) chelator CaEDTA (10 mM) significantly reduced the increase of [Zn(2+)] induced by OGD and reperfusion. Significant regional differences of [Zn(2+)](o) over the areas of the DG, CA1 and CA3 were not observed during I/R. Neither sodium channel blockade by tetrodotoxin (2 microM), perfusion with nominally calcium-free medium nor anatomical disassociation of the DG, CA1 and CA3 regions from one another by lesioning affected the increase of [Zn(2+)](o). The non-specific nitric oxide synthase (NOS) inhibitor, Nomega-nitro-l-arginine methyl ester (1 mM), however, blocked the increase of [Zn(2+)](o) during ischemia and reperfusion. The data indicate the important role of NO in causing the release of Zn(2+) during I/R and suggest that NOS inhibitors may be used to reduce Zn(2+)-induced neuronal injury.
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100
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Qu Z, Wei G, Zhang L, Wu J, Zhang J. [Effect of neurotropin on brain edema induced by permanent focal cerebral ischemia in rats and collateral ventricular injection of carrageenan in mice]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2002; 33:98-101. [PMID: 11938957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Neurotropin, an inhibitor of the kallikrein-kinin system, has been used as an analgesic and anti-allergic drug in the clinic. The aims of this study are to evaluate the effect of neurotropin on brain edema induced by permanent focal cerebral ischemia in rats and collateral ventricular injection of carrageenan in mice and its mechanism. Drugs were given i.v. 15 minutes after middle cerebral artery occlusion in rats and immediately after carrageenan injection in mice. Brain water content was determined by wet/dry weight ratio. Results showed that neurotropin could reduce the brain edema induced by permanent focal cerebral ischemia in rats and collateral ventricular injection of carrageenan in mice at doses of 3.0, 6.0, 30.0 and 30.0 NU.kg-1 body weight. It also suggests that neurotropin reduced ischemic brain edema via inhibiting the kallikrein-kinin system.
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