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Zheng L, Xu J, Qiu W, Liu X, Zhao CM, Chen D, Chen Y. Cardioprotection of exogenous erythropoietin in mice with ligature-induced aortic stenosis: effects on maladaptive cardiac hypertrophy. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2010; 61:13-20. [PMID: 20228410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 01/12/2010] [Indexed: 05/28/2023]
Abstract
Pre-operative treatment with recombinant human erythropoietin may improve aortic stenosis patients' condition, including anemia and/or cardiac dysfunction, for subjecting to aortic valve replacement. In this study, we tested this hypothesis in a mouse model of aortic stenosis. Adult male mice were subjected to either aortic stenosis created by aortic ligature or sham operation. Aortic stenosis for 4 weeks caused cardiac hypertrophy, pulmonary congestion and left ventricular dysfunction. It was associated with increased levels of tumor necrosis factor-alpha in serum and myocardium, and reduced levels of interleukin-10 in myocardium but not in serum. Myocyte apoptosis rate, level of cleaved caspase 3, activity of nuclear factor-kappaB and expression of p38-MAPK pathway were also elevated. Erythropoietin treatment increased hematocrit but did not prevent the development of cardiac hypertrophy. It, however, reduced the apoptosis, prevented the increases in tumor necrosis factor-alpha, nuclear factor-kappaB activation and phosphorylation of p38, and attenuated the increases in lung weight, the decreases in LVEF and LVFS, and the increases in LVDd and LVDs. In conclusion recombinant human erythropoietin has cardioprotective effects in maladaptive cardiac hypertrophy by inhibiting nuclear factor-kappaB activation, phosphorylation of p38-MAPK pathway, and production of tumor necrosis factor-alpha, together leading to a reduced apoptosis.
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877
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Sun MZ, Guo C, Tian Y, Chen D, Greenaway FT, Liu S. Biochemical, functional and structural characterization of Akbu-LAAO: a novel snake venom L-amino acid oxidase from Agkistrodon blomhoffii ussurensis. Biochimie 2010; 92:343-9. [PMID: 20100538 DOI: 10.1016/j.biochi.2010.01.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 01/18/2010] [Indexed: 12/09/2022]
Abstract
An L-amino acid oxidase (Akbu-LAAO) was isolated from the venom of Agkistrodon blomhoffii ussurensis snake using DEAE Sephadex A-50 ion-exchange, Sephadex G-75 gel filtration, and high performance liquid chromatographies. The homogeneity and molecular mass of Akbu-LAAO were analyzed by SDS-PAGE and MALDI-TOF spectrometry. The sequences of ten peptides from Akbu-LAAO were established by HPLC-nESI-MS/MS analysis. Protein sequence alignment indicated that i) that Akbu-LAAO is a new snake venom LAAO, and ii) Akbu-LAAO shares homology with several LAAOs from the venoms of Calloselasma rhodost, Agkistrodon halys, Daboia russellii siamensis, and Trimeresurus stejnegeri. Akbu-LAAO is a homodimer with a molecular mass of approximately 124.4 kDa. It reacts optimally with its enzymatic substrate, Leu, at pH 4.7 with a K(m) of 2.1 mM. ICP-AES measurements showed that Akbu-LAAO contains four Zn(2+) per dimer that are unessential for the hydrolytic activity of the enzyme. The emission fluorescence intensity of Akbu-LAAO decreases by 61% on removal of Zn(2+) indicating that the zinc probably helps maintain the structural integrity of the enzyme. The addition of exogenous metal ions, including Mg(2+), Mn(2+), Ca(2+), Ce(3+), Nd(3+), Co(2+) and Tb(3+), increases the l-Leu hydrolytic activity of the enzyme. Akbu-LAAO shows apparent anti-aggregation effects on human and rabbit platelets. It exhibits a strong bacteriostasis effect on Staphylococcus aureus, eighteen fold that of cephalosporin C under the same conditions. Taken together, the biochemical, proteomic, structural and functional characterizations reveal that Akbu-LAAO is a novel LAAO with promise for biotechnological and medical applications.
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878
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Bedayse N, Hariharan S, Chen D. Red cell transfusion practices and the impact of phlebotomy in an adult intensive care unit in Trinidad--a prospective observational study. W INDIAN MED J 2010; 59:67-72. [PMID: 20931917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVES To determine the pattern of current red cell transfusion practices in an adult intensive care unit (ICU) in Trinidad and the impact of phlebotomy on transfusions. METHODS A prospective observational study was conducted over a six-month period to include all patients who received transfusions in the ICU of Port-of-Spain General Hospital, Trinidad. Demographic data including age, gender and weight were recorded. Clinical data recorded were the admission APACHE II scores, daily phlebotomy volumes, haemoglobin levels, transfusions and outcome during the first thirty days following ICU admission. Patients were grouped according to diagnoses and transfusion patterns. RESULTS Of 134 patients admitted, 40 (29.8%) were transfused packed red cells 18 (29%) of the requests were for single unit transfusion. The mean phlebotomy volume was 13.5 +/- 4.3 (SD) mL day. The adjusted phlebotomy volume to body weight did not correlate with the amount of transfusions. The mean haemoglobin level for triggering blood transfusion was 6.73 g dL. The mean transfusion rate was 2.9 +/- 1.8 (SD) units per patient. Ten per cent of the patients received more than 5 units. Twenty nine per cent of the units were transfused on the first day of ICU admission and 69% were transfused during the first week of LCU stay. CONCLUSIONS Transfusion practices in the study ICU pointed towards a restrictive strategy, although there were some inappropriate transfusions. The phlebotomy volumes did not contribute towards transfusion requirements.
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879
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Aceves SS, Newbury RO, Chen D, Mueller J, Dohil R, Hoffman H, Bastian JF, Broide DH. Resolution of remodeling in eosinophilic esophagitis correlates with epithelial response to topical corticosteroids. Allergy 2010; 65:109-16. [PMID: 19796194 DOI: 10.1111/j.1398-9995.2009.02142.x] [Citation(s) in RCA: 232] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Esophageal remodeling occurs in eosinophilic esophagitis (EE) patients but whether the components of remodeling in the subepithelium are reversible by administration of topical oral corticosteroids is unknown. METHODS We quantitated the degree of lamina propria remodeling in esophageal biopsies obtained before and after at least 3 months of therapy with budesonide in 16 pediatric EE subjects. In addition, we investigated whether corticosteroid therapy modulated vascular activation (expression of VCAM-1; level of interstitial edema), TGFbeta(1) activation (levels of TGFbeta(1), phosphorylated Smad2/3), and performed a pilot analysis of a polymorphism in the TGFbeta(1) promoter in relation to EE subjects who had reduced remodeling with budesonide therapy. RESULTS EE subjects were stratified based on the presence (n = 9) or absence (n = 7) of decreased epithelial eosinophilia following budesonide. Patients with residual eosinophil counts of <or=7 eosinophils per high power field in the epithelial space (responders) demonstrated significantly reduced esophageal remodeling with decreased fibrosis, TGFbeta(1) and pSmad2/3 positive cells, and decreased vascular activation in association with budesonide therapy. Responders were more likely to have a CC genotype at the -509 position in the TGFbeta(1) promoter. CONCLUSIONS Reductions in epithelial eosinophils following budesonide therapy were associated with significantly reduced esophageal remodeling.
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880
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Furnes MW, Zhao CM, Stenstrom B, Arum CJ, Tommeras K, Kulseng B, Chen D. Feeding behavior and body weight development: lessons from rats subjected to gastric bypass surgery or high-fat diet. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2009; 60 Suppl 7:25-31. [PMID: 20388943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Accepted: 12/11/2009] [Indexed: 05/29/2023]
Abstract
Weight loss treatments include diets, drugs, physical training, and surgery, namely bariatric or obesity surgery. The current standard for bariatric surgery is gastric bypass. There are common beliefs that gastric bypass induces body weight loss because of a reduced food intake and that high-fat diet induces overweight and obesity because of overnutrition. The principal aim of the studies on rats summarized herein was to better understand the physiological mechanisms by which gastric bypass achieves body weight loss and by which high-fat diet induces obesity. The results indicated that gastric bypass efficiently reduced body weight, particularly the fat compartment, which was unlikely to be caused by early satiety, reduced food intake or malabsorption, and that large meal size, but not overnutrition, was mainly responsible for high-fat diet-induced obesity. It was unclear whether gastric ghrelin, obestatin and/or amine in the A-like cells were involved in this context.
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881
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Zhang HM, Chen LL, Wang L, Xu S, Wang X, Yi LL, Chen D, Wu ZH, Zhang JY, Liao YF, Shang J. Macrophage infiltrates with high levels of Toll-like receptor 4 expression in white adipose tissues of male Chinese. Nutr Metab Cardiovasc Dis 2009; 19:736-743. [PMID: 19356913 DOI: 10.1016/j.numecd.2008.12.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 12/02/2008] [Accepted: 12/29/2008] [Indexed: 01/22/2023]
Abstract
BACKGROUND AND AIMS Macrophages and Toll-like receptor 4 (TLR4) are involved in the inflammatory process of adipogenesis. This study aimed to characterize macrophage infiltrates and the associated TLR4 expression in different locations of white adipose tissues (WAT) of male Chinese and determine their correlations to adipocyte hypertrophy and hyperplasia. METHODS AND RESULTS A total of 30 men, who were lean, overweight or with type 2 diabetes (T2D), were recruited. Their abdominal omental WAT (oWAT) and subcutaneous WAT (scWAT) were obtained. The contents of macrophages in oWAT and scWAT were quantified using anti-CD68 staining. The levels of TLR4 expression were analyzed by western blot assays and the adipocyte size was quantified, followed by linear regression analysis. Significantly higher numbers of macrophages (24.4+/-3.2 vs 6.1+/-2.9, p<0.001), associated with higher levels of TLR4 expression (0.59+/-0.19 vs 0.20+/-0.03, p<0.001), were observed in oWAT, as compared with that in scWAT. Furthermore, the levels of macrophage infiltrates and TLR4 expression in oWAT of subjects who were overweight or/and have T2D were significantly higher than that in the lean group. The average adipocyte diameters and cross-sectional areas in oWAT of subjects who were overweight were significantly greater than those in the lean group (p=0.003 and p=0.04, respectively). Importantly, the numbers of macrophage infiltrates were positively correlated to the levels of TLR4 expression, the sizes of adipocytes, the levels of body mass index and C-reactive protein, respectively. CONCLUSION Our data suggest that macrophage-related TLR4 expression and inflammation contribute to the development of adipocyte hypertrophy in male Chinese.
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882
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Wang L, Chen D, Cao J, Liu Z. Protective effect of N-acetylcysteine on experimental chronic cadmium nephrotoxicity in immature female rats. Hum Exp Toxicol 2009; 28:221-9. [PMID: 19734274 DOI: 10.1177/0960327109102365] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In the present study, female Sprague-Dawley rats received CdCl(2) (50 mg/L through drinking water) and/or N-acetylcysteine (NAC, 120 mg/kg/day, orally) to investigate the protective effect of NAC on Cd-induced renal damage. Renal toxicity was evaluated by measuring the contents of total protein, beta(2)-microglobulin, and alpha(1)-microglobulin in the urine and urinary enzyme markers of tubular necrosis, as well as levels of serum urea nitrogen and serum creatinine. Activities of antioxidant enzymes and contents of glutathione, malondialdehyde, and trace elements in the kidney were also measured. Animals that received both Cd and NAC showed a better renal function than those receiving Cd alone. In addition, NAC significantly reduced the levels of lipid peroxidation (LPO) in the kidney of cadmium-treated rats. The enzymic and nonenzymatic antioxidants levels are not restored, but their further decrease is prevented by NAC. Also NAC administration does not modify the urinary excretion of cadmium or contents of cadmium in the serum and kidney. In conclusion, NAC exerts its protective effect by decreased LPO and improving antioxidants status to prevent renal tubular damage induced by chronic Cd administration, most probably through its antioxidant properties.
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883
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Chen D, Zuo G, Li C, Hu X, Guan T, Jiang R, Li J, Lin X, Li F, Luo C, Wang H, Lei C, Long X, Wang Y, Wang J. Total saponins of Panax ginseng (TSPG) promote erythroid differentiation of human CD34+ cells via EpoR-mediated JAK2/STAT5 signaling pathway. JOURNAL OF ETHNOPHARMACOLOGY 2009; 126:215-220. [PMID: 19735711 DOI: 10.1016/j.jep.2009.08.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 08/27/2009] [Accepted: 08/30/2009] [Indexed: 05/28/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Total saponins of Panax ginseng (TSPG), main constituents extracted from Panax ginseng, a highly valued traditional Chinese medicine, have been shown to be an effective agent on hematopoiesis. OBJECTIVE To investigate the effect and mechanism underlying in which TSPG promote human CD34(+) hematopoietic stem and progenitor cells to differentiate into erythroid-lineage cells. MATERIALS AND METHODS The effect of TSPG on erythroid differentiation of purified CD34(+) cells derived from umbilical cord blood (UCB) was determined by methylcellulose assay system and colorimetry for hemoglobin content. The changes of EpoR expression in umbilical cord blood mononuclear cells (UCB-MNCs) and purified CD34(+) cells were detected with Western blotting and flow cytometry, respectively, and observed under laser scanning confocal microscope (LSCM). RT-PCR was performed to examine EpoR mRNA expression in CD34(+) cells. The effects of TSPG-pretreatment on Epo-induced JAK(2) and STAT(5) tyrosine phosphorylation were analyzed by immunoprecipitation. RESULTS The addition of TSPG (20-70 mg/L) increased the colony formation rate of BFU-E. TSPG (50 mg/L) alone used significantly increased the hemoglobin content, the addition of AG490 evidently reduced TSPG-induced elevation of hemoglobin content. TSPG increased the expression of EpoR on the surface membrane of CD34(+) cells but did not change the expression of EpoR in total UCB-MNCs. TSPG also increased the expression of EpoR mRNA in CD34(+) cells. TSPG markedly enhanced Epo-induced tyrosine phosphorylation of JAK(2) and STAT(5) in UCB-MNCs. CONCLUSION These findings suggest that TSPG may enhance the erythroid differentiation of hematopoietic stem and progenitor cells via Epo/EpoR-mediated JAK(2)/STAT(5) signaling pathway.
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884
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Liu H, Zhang H, Chen D, Kuang J, Di X. O1045 Establishment of a preeclampsia/eclampsia scoring system for evaluation of the severity and outcomes. Int J Gynaecol Obstet 2009. [DOI: 10.1016/s0020-7292(09)61418-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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885
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Wang F, Wu S, Song Y, Tang X, Marshall R, Liang M, Wu Y, Qin X, Chen D, Hu Y. Waist circumference, body mass index and waist to hip ratio for prediction of the metabolic syndrome in Chinese. Nutr Metab Cardiovasc Dis 2009; 19:542-547. [PMID: 19188050 DOI: 10.1016/j.numecd.2008.11.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 10/21/2008] [Accepted: 11/10/2008] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS To explore the ability of waist circumference (WC), body mass index (BMI) and waist to hip ratio (WHR) to predict two or more non-adipose components of the metabolic syndrome (MetS) among individuals aged 18-85 in North China. METHODS AND RESULTS This study is a cluster sample survey of 101,510 individuals, complete data are 75,788 subjects, 59,874 males and 15,914 females. Their ages were 51.9+/-12.7 years (males) and 48.7+/-11.5 years (females). Receiver operating characteristic (ROC) analysis was used to examine discrimination and find optimal cut off values of WC, BMI and WHR to predict two or more non-adipose components of MetS. The area under the ROC curve (AURC) for WC (0.694) and BMI (0.692) in females showed no difference. In males BMI (0.657) had a better discrimination than WC (0.634). WHR was weaker in both sexes. The optimal cut off value of WC in males (86.5 cm) was higher than in females (82.1cm); and that of BMI was about 24 kg/m(2) in both genders. The optimal cut off values of WC, BMI, and WHR, increased with age in both sexes. CONCLUSIONS BMI and WC are more useful than WHR for predicting two or more non-adipose components of MetS. Cut off values for WC in males, and those of BMI and WHR in both sexes are lower than that in present MetS criteria; WC in females is slightly higher. Cut off values of WC, BMI and WHR were increased with age in the Chinese.
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886
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Di X, Liu H, Chen D, Kuang J, Huang D. O220 Concurrent eclampsia and HELLP syndrome is a catastrophic event. Int J Gynaecol Obstet 2009. [DOI: 10.1016/s0020-7292(09)60592-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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887
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Jonason JH, Xiao G, Zhang M, Xing L, Chen D. Post-translational Regulation of Runx2 in Bone and Cartilage. J Dent Res 2009; 88:693-703. [PMID: 19734454 DOI: 10.1177/0022034509341629] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The Runx2 gene product is essential for mammalian bone development. In humans, Runx2 haploinsufficiency results in cleidocranial dysplasia, a skeletal disorder characterized by bone and dental abnormalities. At the molecular level, Runx2 acts as a transcription factor for genes expressed in hypertrophic chondrocytes and osteoblasts. Runx2 gene expression and protein function are regulated on multiple levels, including transcription, translation, and post-translational modification. Furthermore, Runx2 is involved in numerous protein-protein interactions, most of which either activate or repress transcription of target genes. In this review, we discuss expression of Runx2 during development as well as the post-translational regulation of Runx2 through modification by phosphorylation, ubiquitination, and acetylation.
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888
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Chen D. Congratulations. Am J Hypertens 2009. [DOI: 10.1038/ajh.2009.143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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889
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Chen D, Chen JJ, Yin Q, Guan JH, Liu YH. Role of ERK1/2 and vascular cell proliferation in cerebral vasospasm after experimental subarachnoid hemorrhage. Acta Neurochir (Wien) 2009; 151:1127-34. [PMID: 19444374 DOI: 10.1007/s00701-009-0385-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 04/17/2009] [Indexed: 11/24/2022]
Abstract
BACKGROUND Although there are still some unresolved aspects, current research has revealed that vascular cell proliferation probably plays an important part in the pathological formation process of cerebral vasospasm. Using a "two-hemorrhage" model of subarachnoid hemorrhage (SAH), this study investigated the function of ERK1/2 and vascular wall cell proliferation in pathological development of cerebral vasospasm. METHODS Fifty rabbits were randomly divided into five groups: (1) SAH day 1, (2) SAH day 3, (3) SAH day 7, (4) SAH + DMSO (dimethyl sufoxide) solution, (5) SAH + PD98059 (a mitogen-activated protein kinase inhibitor) dissolved in DMSO solution. In the SAH + PD98059/DMSO group and SAH + DMSO control group, PD98059 in DMSO (2 mmol/l) or an equal quantity of DMSO, respectively, was injected into the cisterna magna, once a day from SAH day 1 to day 3. Western protein blotting was used to detect the expression of proliferating cell nuclear antigen (PCNA) and extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in each group's basilar arteries. Light microscopy and electron microscopy were used for dynamic histological detection at each observation point of the SAH vascular wall under the effects of SAH and the mitogen-activated protein kinase inhibitor. Another 18 rabbits were randomly divided into three groups: SAH, SAH + DMSO and SAH + PD98059/DMSO; cerebral angiograpathy was conducted on SAH days 1 and 7, and the progression of angiographic vasospasm evaluated. RESULTS Compared with the control group, the extent of vasospasm after SAH increased with time. PD98059 significantly reduced angiographic and morphological vasospasm. In cerebral vasospasm, the expression of T-ERK1/2 showed no significant change. However, expression of p-ERK1/2 and PCNA began to increase significantly on day 3, and achieved a peak on day 7. PD98059 significantly inhibited the expression of p-ERK1/2 and PCNA (p < 0.05). CONCLUSIONS Cell proliferation on the vascular wall plays an important part in the pathological formation process of cerebral vasospasm. ERK1/2 phosphorylation, as an important signaling pathway, taking part in the process of vascular-wall pathological proliferation of cerebral vasospasm.
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MESH Headings
- Animals
- Basilar Artery/cytology
- Basilar Artery/enzymology
- Cell Proliferation
- Disease Models, Animal
- Enzyme Activation/physiology
- Enzyme Inhibitors/pharmacology
- Flavonoids/pharmacology
- Hypertrophy/drug therapy
- Hypertrophy/enzymology
- Hypertrophy/physiopathology
- Microscopy, Electron
- Mitogen-Activated Protein Kinase 3/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/enzymology
- Proliferating Cell Nuclear Antigen
- Rabbits
- Subarachnoid Hemorrhage/complications
- Up-Regulation/physiology
- Vasospasm, Intracranial/drug therapy
- Vasospasm, Intracranial/enzymology
- Vasospasm, Intracranial/physiopathology
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890
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Hough LE, Jung HT, Krüerke D, Heberling MS, Nakata M, Jones CD, Chen D, Link DR, Zasadzinski J, Heppke G, Rabe JP, Stocker W, Körblova E, Walba DM, Glaser MA, Clark NA. Helical Nanofilament Phases. Science 2009; 325:456-60. [DOI: 10.1126/science.1170027] [Citation(s) in RCA: 265] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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891
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Frederick K, Maurer T, Kalgutkar A, Royer L, Francone O, Winter S, Terra S, Chen D, Gao X. Pharmacokinetics, disposition and lipid-modulating activity of 5-{2-[4-(3,4-difluorophenoxy)-phenyl]-ethylsulfamoyl}-2-methyl-benzoic acid, a potent and subtype-selective peroxisome proliferator-activated receptor α agonist in preclinical species and human. Xenobiotica 2009; 39:766-81. [DOI: 10.1080/00498250903121796] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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892
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Liu XJ, Ye HX, Li WP, Dai R, Chen D, Jin M. Relationship between psychosocial factors and onset of multiple sclerosis. Eur Neurol 2009; 62:130-6. [PMID: 19571540 PMCID: PMC2790740 DOI: 10.1159/000226428] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 05/12/2009] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the influence of psychosocial variables on patients with multiple sclerosis (MS) and the relationship between these variables and the onset of MS. BACKGROUND The current evidence indicates that many types of psychosocial factors are involved in the development and relapse of MS, and it has been suggested that they could serve as predictors as well. So far, little has been reported on the effect of psychosocial factors on MS and the relationship between psychosocial factors and the onset of MS. METHODS Forty-one patients, 15 males and 26 females, average age 37.44 +/- 12.24 years (mean +/- SD), were evaluated by the Life Event Scale, Eysenck Personality Questionnaire, Social Support Revaluate Scale and Symptom Check List 90 and compared with 41 equivalent healthy control subjects, 15 males and 26 females, average age 36.38 +/- 12.84 years (mean +/- SD). Disease, demographic, psychosocial and lifestyle factors were measured at baseline. Patients with MS were first diagnosed by 3 neurologists according to the Poser (1983) MS diagnostic criteria. RESULTS Significant differences were found between the MS and the control group in their negative emotions and symptoms such as depression, anxiety, obsession, phobia, tense interpersonal relationship and somatization disorder. Significant differences were found between the two groups in the total number of negative life events, their family problems and the utilization of social support. The scores for various negative emotions in the MS group correlated positively with those for neuroticisms in personality type, and negatively with those for introverted and extroverted personality. Many kinds of negative emotions in the MS group correlated positively with the total number of life events, negative life events and family problems. Many kinds of negative emotions in the MS group correlated negatively with the utilization of social support. CONCLUSION The psychosocial factors are closely associated with MS onset and may play important roles in the development of the disease.
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893
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Abstract
Thrombin can amplify inflammation induced by other stimuli, either through ischemia (consequent upon thrombosis), indirectly through generation of downstream mediators such as activated protein C, or directly via signals through protease activated receptors (PAR). This paper will summarize recent data from our laboratory indicating that thrombin is required to initiate CCR2-dependent leukocyte recruitment and that it is the principal determinant of the outcome after vascular injury, via PAR-1 activation of a distinct subset of smooth muscle cell progenitors. In both, tissue factor (TF) initiates thrombin generation and the thrombin acts locally, exemplifying that the initiation phase can generate autocrine or paracrine signalling molecules. Thrombin is an important constituent of innate immunity, able to amplify and modify responses to invading pathogens or tissue damage. With novel anti-thrombin therapeutics and agents to target PAR, a new understanding of the importance of thrombin may allow the development of innovative anti-inflammatory strategies.
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894
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Liu C, Liu Y, Chen D, Tang Z, Pan W, Wery J, Chen Y. Establishment of human primary non-small cell lung cancer xenograft models for test of cytotoxic and targeted anticancer drugs. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.11008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
11008 Background: New oncology drug development has moved from general cytotoxic agents to molecular target-directed therapeutics. Consequently, there is a need to identify tumor types and individual patient tumors that express the target and could benefit from more selective therapies in clinical trials. Therefore, the in vivo models used in preclinical development should be“disease-oriented” and target-directed. Recently, we developed non-small cell lung cancer (NSCLC) xenograft models by transplanting human fresh tumor fragments into nude mice, which have been used for test of cytotoxic and targeted anticancer drugs. Methods: The fresh NSCLC tumors were collected from local hospitals. The tumor fragments were subcutaneously implanted into nude mice. The EGFR and K-ras mutation status of the tumors were investigated and compared with the efficacy results. The test drugs included paclitaxel, gemcitabine, and the epidermal growth factor receptor (EGFR) inhibitor erlotinib. Results: A total of 72 NSCLC samples were implanted, and 13 tumor models were established (tumor taking rate 18%) for the first passage. The tumor taking rates were higher in the second and third passages (80–100%). Paclitaxel and gemcitatbine produced tumor growth inhibition rates of 50–53% regardless of the EGFR and K-ras mutation status. While erlotinib demonstrated a significant antitumor activity only in the tumors bearing EGFR mutation with wild-type K-ras, which were consistent with their clinical findings. The tumor xenografts’ architecture, the cell and histopathological morphology from the three generations mirrored the original patient cancers. Conclusions: These results suggest that human primary tumor xenograft models provide a unique renewable source of tumor material for test of novel anticancer agents. They may predict more relevant clinical response rates and higher correlation with clinical findings than use of xenograft models established from long-term cultured cancer cell lines, especially for test of target-oriented therapeutics in new drugs development programs. No significant financial relationships to disclose.
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895
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Chen D, Ge J, Wang L, Gao Q, Ma P, Li N, Li DQ, Wang Z. A simple and evolutional approach proven to recanalise the nasolacrimal duct obstruction. Br J Ophthalmol 2009; 93:1438-43. [PMID: 19416937 PMCID: PMC2760725 DOI: 10.1136/bjo.2008.149393] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Aim: To evaluate a new approach of recanalisation of nasolacrimal duct obstruction (RC-NLDO) in the treatment of the nasolacrimal duct obstruction (NLDO) and chronic dacryocystitis. Methods: 583 patients with 641 eyes suffering from NLDO and chronic dacryocystitis were enrolled in this study. The RC-NLDO was performed in 506 eyes, with 135 eyes undergoing external dacryocystorhinostomy (EX-DCR) as controls. Patient follow-up for 54 months was evaluated by symptoms, dye disappearance test, lacrimal irrigation and digital subtraction dacryocystogram. The RC-NLDO was also performed in 12 rhesus monkeys for histopathological examination. Results: The clinical success rates were 93.1% in 506 cases of RC-NLDO and 91.11% in 135 cases of EX-DCR. The success rates for second surgery were achieved in 85.19% on RC-NLDO and 40.0% on EX-DCR. No major intra- or postoperative complications were observed in the RC-NLDO group. The mean operative duration was 12.5 min for RC-NLDO and 40.3 min for EX-DCR (p<0.001). A pathological study in rhesus monkeys demonstrated that the RC-NLDO wounded epithelium in nasolacrimal duct healed completely within 1 month without granulation tissue formation. Conclusion: The findings demonstrate that the RC-NLDO is a simple and effective approach proven to recanalise the obstructed nasolacrimal duct with a comparable success rate to EX-DCR.
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896
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Cheng Y, Tao M, Riley L, Kann L, Ye L, Tian X, Tian B, Hu J, Chen D. Protective factors relating to decreased risks of adolescent suicidal behaviour. Child Care Health Dev 2009; 35:313-22. [PMID: 19397597 DOI: 10.1111/j.1365-2214.2009.00955.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Suicide has been identified as one of the three leading causes of death in adolescents and young adults. No previous study in China has tested the association between protective factors and urban adolescents' suicidal behaviours. In this study we tested the hypothesis that suicidal behaviours would be associated with multiple protective factors. METHODS A stratified random of 9015 students from 100 junior middle schools in Beijing, Hangzhou, Wuhan and Urumqi completed the Chinese version of Global School-Based Student Health Survey. RESULTS Overall, 17.4% of students had seriously considered attempting suicide, and 8.1% had made a specific plan to attempt suicide during the 12 months preceding the survey. The students in Wuhan (18.7%) and Urumqi (20.8%) cities were significantly more likely than students in Beijing (14.4%) and Hangzhou (14.4%) to have suicidal ideation (chi2 = 45.9, P < 0.001). Female students were significantly more likely than male students to have suicidal ideation and have made suicide attempts [odds ratio (OR) = 1.4, P < 0.001]. Results indicated that the rates of suicidal ideation and suicide attempts increased with age (OR = 1.44, P < 0.001). Multivariate logistic regression models showed that suicide risk tended to decrease significantly when 'days of missed classes or school without permission were less than one', and when students thought students in their school were kind and helpful most of the time or always', 'parents or guardians checked to see if homework was done most of the time or always', 'parents or guardians understood their problems and worries most of the time or always' and 'parents or guardians really know what they are doing with their free time most of the time or always'. CONCLUSIONS Adolescent suicide behaviour should be a serious problem. Measures can be taken to prevent suicide by observing the factors significantly linked to suicidal behaviour. Steps can then be taken to identify adolescents who have serious suicidal ideation so that intervention can be taken to reduce the suicidal rate.
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897
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Bulun SE, Lin Z, Zhao H, Lu M, Amin S, Reierstad S, Chen D. Regulation of aromatase expression in breast cancer tissue. Ann N Y Acad Sci 2009; 1155:121-31. [PMID: 19250199 DOI: 10.1111/j.1749-6632.2009.03705.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Epithelial-stromal interactions play key roles for aromatase expression and estrogen production in breast cancer tissue. Upregulated aromatase expression in breast fibroblasts increases the tissue concentration of estradiol (E2), which then activates a large number of carcinogenic genes via estrogen receptor-alpha (ERalpha) in malignant epithelial cells. This clinically pertains, since aromatase inhibitors (AIs) are the most effective hormonal treatment of ERalpha-positive breast tumors. A single gene encodes aromatase, the key enzyme in estrogen biosynthesis, the inhibition of which by an AI effectively eliminates E2 production. Since alternative promoters regulated by distinct signaling pathways control aromatase expression, it is possible to target these pathways and inhibit estrogen production in a tissue-selective fashion. We and others previously found that the majority of estrogen production in breast cancer tissue was accounted for by the aberrant activation of the proximal promoter I.3/II region. PGE(2) that is secreted in large amounts by malignant breast epithelial cells is the most potent known natural inducer of this promoter region in breast adipose fibroblasts. Signaling effectors/transcriptional regulators that mediate PGE(2) action include the activator pathways p38/CREB-ATF and JNK/jun and the inhibitory factor BRCA1 in breast adipose fibroblasts. Selective inhibition of this promoter region may treat breast cancer while permitting aromatase expression via alternative promoters in the brain and bone and thus obviate the key side effects of the current AIs. The signaling pathways that mediate the regulation of the promoter I.3/II region in undifferentiated fibroblasts in malignant breast tumors are reviewed.
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898
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Cao X, Xu Y, Chen D, Qiao H. Associated evolution of a support vector machine-based classifier for pedestrian detection. Inf Sci (N Y) 2009. [DOI: 10.1016/j.ins.2008.10.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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899
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Tan RS, Carrejo MH, Chen D. An unusual case of vascular hypogonadism treated with clomiphene citrate and testosterone replacement. Andrologia 2009; 41:63-5. [PMID: 19143734 DOI: 10.1111/j.1439-0272.2008.00891.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Many male patients are discovered on screening to suffer from hypogonadism and age related hypogonadism is being increasingly recognized. However, secondary causes of hypogonadism should not be overlooked, especially in patients who may have concomitant morbidity as highlighted in this case. Our patient with vascular hypogonadism was treated with testosterone and clomiphene citrate in cycles; with a hope of improving not only androgen levels but overall pituitary function as there were co-existing endocrine pathologies of albeit primary hypothyroidism and low IGF-1 levels. Treatment with exogenous testosterone is fairly well established; but there is also increasing evidence of the effectiveness and short-term safety of clomiphene citrate in restoring not only biological levels but functional states in males as well. As such, we report an unusual case of a patient seen at our Men's Health & Andrology clinic in which both the cause of some otherwise unremarkable symptoms and the treatment, using a combination of clomiphene citrate and testosterone, were remarkable.
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900
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Chen D, Barber C, McLoughlin P, Thavaneswaran P, Jamieson GG, Maddern GJ. Systematic review of endoscopic treatments for gastro-oesophageal reflux disease. Br J Surg 2009; 96:128-36. [PMID: 19160349 DOI: 10.1002/bjs.6440] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND The aim of this review was to assess the safety and efficacy of endoscopic procedures for gastro-oesophageal reflux disease. METHODS Literature databases including Medline, Embase and PubMed were searched up to May 2006 without language restriction. Randomized controlled trials and non-randomized comparative studies with at least ten patients in each study arm, and case series studies of at least ten patients, were included. RESULTS A total of 33 studies examining seven endoscopic procedures (Stretta procedure, Bard EndoCinch, Wilson-Cook Endoscopic Suturing Device, NDO Plicator, Enteryx, Gatekeeper Reflux Repair System and Plexiglas) were included in the review. Of the three procedures that were tested against sham controls (Stretta procedure, Bard EndoCinch and Enteryx), patient outcomes in the treatment group were either as good as, or significantly better than, those of control patients in terms of heartburn symptoms, quality of life and medication usage. However, for the two procedures that were tested against laparoscopic fundoplication (Stretta) procedure and Bard EndoCinch), outcomes for patients in the endoscopic group were either as good as, or inferior to, those for the laparoscopic group. CONCLUSION At present there is insufficient evidence to determine the safety and efficacy of endoscopic procedures for gastro-oesophageal reflux disease, particularly in the long term.
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