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Yan M, Lu R, Jia X, Meng F, Zhao X. [Different serum lipid adjustment drugs for the treatment of hyperlipidemic fatty liver]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9:355-7. [PMID: 11782305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To research the effect of different serum lipid adjustment drugs, Simvastatin and Fenofibrate, on hyperlipidemic fatty liver. METHODS The rat models of hyperlipidemic fatty liver induced by high fat diet were treated with Fenofibrate and Simvastatin respectively to investigate the change of the liver index, liver function, the serum and liver lipid, MDA, and pathologic histology. RESULTS The liver index and the content of triglyceride (TC1.80 +/-0.20/2.10+/-0.33), total cholesterol (TG 0.76+/-0.18/1.09+/-0.31), MDA both in the serum and the liver in the model group were significantly higher than those in control group. Slight or moderate hepatic steatosis was observed in model group. Fenofibrate decreased serum triglyceride, total cholesterol, and MDA both in serum and liver significantly, but increased the ALT, ALP, liver index, liver lipids, and finally leading to severe hepatic steatosis. Simvastatin lowered the level of lipid and MDA both in serum and liver, and liver histology was improved nearly to normal. Moreover, little side effect on the liver was observed. CONCLUSIONS Simvastatin can be applied for prevention and treatment of hyperlipidemic fatty liver safely and effectively, while Fenofibrate can not.
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Lu R, Pitha PM. Monocyte differentiation to macrophage requires interferon regulatory factor 7. J Biol Chem 2001; 276:45491-6. [PMID: 11585813 DOI: 10.1074/jbc.c100421200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interferon regulatory factors are a growing family of transcription factor that have been implicated in cellular events such as cell-growth regulation, antiviral defense, and development of the immune system. Interferon regulatory factor 7 (IRF-7) is expressed predominantly in lymphoid tissues and has been studied extensively in the context of viral infection and the induction of interferon and cytokine gene expression. In this paper, the involvement of IRF-7 in monocyte differentiation was examined in U937, HL60, and human primary macrophages. We report the induction of IRF-7 expression by 12-O-tetradecanoylphorbol-13-acetate in U937 and HL60 cells and demonstrate that this induction is essential for the monocyte differentiation to macrophages. We show that the monocyte differentiation is inhibited in cells expressing a dominant negative IRF-7 mutant, as evidenced by decreased expression of two macrophage-differentiation markers, CD11b and CD11c, and impaired phagocytic activity. In addition, we demonstrate that overexpression of IRF-7 is sufficient to trigger monocyte differentiation and to induce cell cycle arrest. The identification of IRF-7 as a key regulator in monocyte differentiation suggests a novel function of IRF-7 in innate immunity.
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Peng J, Lu R, Ye F, Deng HW, Li YJ. Induction of alpha-calcitonin gene-related peptide mRNA expression in rat dorsal root ganglia by heat stress involves the heme oxygenase-1/carbon monoxide pathway. Neuropeptides 2001; 35:297-302. [PMID: 12030815 DOI: 10.1054/npep.2001.0880] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
SD rats were pretreated with whole body hyperthermia (rectal 42 degrees C) for 15 min. The level of calcitonin gene-related peptide (CGRP) in plasma, and alpha- and beta-CGRP mRNA as well as heme oxygenease-1 and heme oxygenase-2 mRNA in dorsal root ganglia were determined by radioimmunoassay and semi-quantitative reverse-transcription polymerase chain reaction, respectively. Heat stress induced only the expression of alpha-CGRP or heme oxygenease-1 but not beta-CGRP or heme oxygenase-2 mRNA, and the release of CGRP and induction of alpha-CGRP mRNA expression were abolished by pretreatment with Zinc protoporphyrin IX, the heme oxygenase inhibitor, or methylene blue, the inhibitor of soluble guanylate cyclase. These results indicate that induction of alpha-CGRP mRNA expression in rat DRG by heat stress involves the heme oxygenase-1/carbon monoxide pathway.
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Sun T, Echelard Y, Lu R, Yuk DI, Kaing S, Stiles CD, Rowitch DH. Olig bHLH proteins interact with homeodomain proteins to regulate cell fate acquisition in progenitors of the ventral neural tube. Curr Biol 2001; 11:1413-20. [PMID: 11566099 DOI: 10.1016/s0960-9822(01)00441-9] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Organizing signals such as Sonic hedgehog are thought to specify neuronal subtype identity by regulating the expression of homeodomain proteins in progenitors of the embryonic neural tube. One of these, Nkx2.2, is necessary and sufficient for the development of V3 interneurons. RESULTS We report that Olig genes, encoding basic helix-loop-helix (bHLH) proteins, are expressed in a subset of Nkx2.2 progenitors before the establishment of interneurons and oligodendroglial precursors. Gain-of-function analysis in transgenic mouse embryos indicates that Olig genes specifically inhibit the establishment of Sim1-expressing V3 interneurons. Moreover, coexpression of Olig2 with Nkx2.2 in the chick neural tube generated cells expressing Sox10, a marker of oligodendroglial precursors. Colocalization of Olig and Nkx2.2 proteins at the dorsal extent of the Nkx2.2 expression domain is consistent with regulatory interactions that define the potential of progenitor cells in the border region. CONCLUSIONS Interactions between homeodomain and Olig bHLH proteins evidently regulate neural cell fate acquisition and diversification in the ventral neural tube. In particular, interactions between Olig and Nkx2.2 proteins inhibit V3 interneuron development and promote the formation of alternate cell types, including those expressing Sox10.
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Xiao L, Lu R, Hu CP, Deng HW, Li YJ. Delayed cardioprotection by intestinal preconditioning is mediated by calcitonin gene-related peptide. Eur J Pharmacol 2001; 427:131-5. [PMID: 11557265 DOI: 10.1016/s0014-2999(01)01231-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Previous studies have shown that nitric oxide and calcitonin gene-related peptide (CGRP) are involved in mediation of the delayed cardioprotection of ischemic or pharmacological preconditioning, and nitric oxide can evoke the release of CGRP. In the present study, we examined the role of CGRP in nitric oxide-mediated delayed cardioprotection by brief intestinal ischemia in rats. The serum concentration of creatine kinase and infarct size were measured after 45-min coronary artery occlusion and 180-min reperfusion. Ischemic preconditioning was induced by six cycles of 4-min ischemia and 4-min reperfusion of the small intestine. Pretreatment with intestinal ischemic preconditioning for 24, 48, or 72 h significantly reduced infarct size and creatine kinase release, and the effects of ischemic preconditioning were completely abolished by L-nitroarginine methyl ester (L-NAME, 10 mg/kg, i.p.), an inhibitor of nitric oxide synthase, or by pretreatment with capsaicin (50 mg/kg, s.c.), which selectively depletes transmitters in capsaicin-sensitive sensory nerves. Intestinal preconditioning caused a significant increase in plasma concentrations of CGRP, and the effect was also abolished by L-NAME or capsaicin. These results suggest that the delayed cardioprotection afforded by intestinal ischemic preconditioning is mediated by endogenous CGRP via the nitric oxide pathway.
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Nakajima N, Lu R, Engelman A. Human immunodeficiency virus type 1 replication in the absence of integrase-mediated dna recombination: definition of permissive and nonpermissive T-cell lines. J Virol 2001; 75:7944-55. [PMID: 11483739 PMCID: PMC115038 DOI: 10.1128/jvi.75.17.7944-7955.2001] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Functional retroviral integrase protein is thought to be essential for productive viral replication. Yet, previous studies differed on the extent to which integrase mutant viruses expressed human immunodeficiency virus type 1 (HIV-1) genes from unintegrated DNA. Although one reason for this difference was that class II integrase mutations pleiotropically affected the viral life cycle, another reason apparently depended on the identity of the infected cell. Here, we analyzed integrase mutant viral infectivities in a variety of cell types. Single-round infectivity of class I integration-specific mutant HIV-1 ranged from <0.03 to 0.3% of that of the wild type (WT) across four different T-cell lines. Based on this approximately 10-fold influence of cell type on mutant gene expression, we examined class I and class II mutant replication kinetics in seven different cell lines and two primary cell types. Unexpectedly, some cell lines supported productive class I mutant viral replication under conditions that restricted class II mutant growth. Cells were defined as permissive, semipermissive, or nonpermissive based on their ability to support the continual passage of class I integration-defective HIV-1. Mutant infectivity in semipermissive and permissive cells as quantified by 50% tissue culture infectious doses, however, was only 0.0006 to 0.005% of that of WT. Since the frequencies of mutant DNA recombination in these lines ranged from 0.023 to <0.093% of the WT, we conclude that productive replication in the absence of integrase function most likely required the illegitimate integration of HIV-1 into host chromosomes by cellular DNA recombination enzymes.
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Zhang W, Yu H, Wang X, Wang Q, Lu R, Wang HQ, Shao JJ. [Analysis of the nucleotide sequence for C and NS5 regions and the genotype of HCV isolate in Shandong Province]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 2001; 15:219-21. [PMID: 11986688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To study the genotype of HCV epidemic strains in Shandong Province. METHODS HCV fragments of C(432 bp) and NS5(319 bp) regions were amplified by RT nested PCR. The fragments were cloned to T vector and sequenced by dideoxynucleotide chain termination reaction. RESULTS Three of all 4 strains in C region were 1b genotype, and 1 was 2a. All of 10 strains of NS5 region were 1b genotype. No other genotype was found in this region. The homology of nucleotide sequence was over 90% compared with that of more than 50 strains in Gen Bank. CONCLUSIONS The major genotype of HCV epidemic strains in Shandong Province is 1b. The 2a genotype is also found in this area.
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Yang SM, Fang DC, Luo YH, Lu R, Battle PD, Liu WW. Alterations of telomerase activity and terminal restriction fragment in gastric cancer and its premalignant lesions. J Gastroenterol Hepatol 2001; 16:876-82. [PMID: 11555101 DOI: 10.1046/j.1440-1746.2001.02540.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
AIMS In order to explore the role of alterations of telomerase activity and terminal restriction fragment (TRF) length in the development and progression of gastric cancer. METHODS Telomerase activity was detected in 176 specimens of gastric mucosa obtained through an operation or endoscopical biopsy by using the telomeric repeat amplification protocol (TRAP) assay. Meanwhile, the mean length of TRF was measured with the use of a Southern blot in part of those samples. RESULTS Telomerase activity was detected in 14 of 57 (24.6%) chronic atrophy gastritis patients, six of 18 (33.3%) intestinal metaplasia patients, three of eight (37.5%) dysplasia patients and 60 of 65 (92.3%) gastric cancer patients, respectively. Normal gastric mucosa revealed no telomerase activity. No association was found between telomerase activity and any clinicopathological parameters. The mean TRF length was decreased gradually with age in normal mucosa and in gastric cancer tissue. Regression analysis demonstrated that the reduction rate in these tissues was 41 +/- 12 base pairs/year. Among 35 gastric cancers, TRF length was shown to be shorter in 20 cases (57.1%), similar in 12 cases (34.3%) and elongated in three cases (7.6%), compared to the corresponding adjacent tissues. The mean TRF length tended to decrease as the mucosa underwent chronic atrophy gastritis, intestinal metaplasia, dysplasia and into gastric cancer. The mean TRF length in gastric cancer was not statistically correlated with clinicopathological parameters and telomerase activity. CONCLUSIONS Our results suggest that telomerase is expressed during the early stage of gastric carcinogenesis, and that the clinical significance of TRF length appears to be limited in gastric cancer.
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Sun Z, Lu R, Xu J, Zhang Z, Li S. [Studies on cloning and expression of hepatitis B virus x gene]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9 Suppl:6-8. [PMID: 11509125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To express and purify the x gene of hepatitis B virus (HBV), and then the purity of the protein could specifically be analysed by the human antibodies against HBV x antigen (protein). METHODS HBV x gene was amplified from the complete genome by PCR, and cloned in the pGEX-2T fused expression vector. After transforming the plasmid into E.coli, the recombinant with HBx gene was obtained. The fusion protein was generated with E.coli fused expression system and purified with affinity chromatography. RESULTS The HBx protein could be applied to detecting specific antibody of hepatitis B virus patients. CONCLUSIONS The purity of the HBx protein can specifically be recognized by the human antibodies against HBV x antigen.
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Lu R, Hu CP, Deng HW, Li YJ. Calcitonin gene-related peptide-mediated ischemic preconditioning in the rat heart: influence of age. REGULATORY PEPTIDES 2001; 99:183-9. [PMID: 11384781 DOI: 10.1016/s0167-0115(01)00253-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In the present study, we examined whether age-related reduction of ischemic preconditioning is related to calcitonin gene-related peptide (CGRP) release in the rat heart. Thirty minutes of global ischemia and 40 min of reperfusion caused a significant decrease of cardiac function and a marked increase of creatine kinase (CK) release at 2, 6 and 20 months of age. Ischemic preconditioning and pretreatment with CGRP for 5 min significantly improved cardiac function and reduced CK release during reperfusion at 2 and 6 months of age but not at 20 months of age. The content of CGRP in the coronary effluent during ischemic preconditioning was significantly increased in the first cycle at 2, 6 months of age but not at 20 months of age. These results suggest that the protection afforded by ischemic preconditioning is decreased in aging hearts, and the age-related change may be related to reduction of the release and effect of CGRP in the rat heart.
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111
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Di Pierro M, Lu R, Uzzau S, Wang W, Margaretten K, Pazzani C, Maimone F, Fasano A. Zonula occludens toxin structure-function analysis. Identification of the fragment biologically active on tight junctions and of the zonulin receptor binding domain. J Biol Chem 2001; 276:19160-5. [PMID: 11278543 DOI: 10.1074/jbc.m009674200] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Zonula occludens toxin (Zot) is an enterotoxin elaborated by Vibrio cholerae that increases intestinal permeability by interacting with a mammalian cell receptor with subsequent activation of intracellular signaling leading to the disassembly of the intercellular tight junctions. Zot localizes in the bacterial outer membrane of V. cholerae with subsequent cleavage and secretion of a carboxyl-terminal fragment in the host intestinal milieu. To identify the Zot domain(s) directly involved in the protein permeating effect, several zot gene deletion mutants were constructed and tested for their biological activity in the Ussing chamber assay and their ability to bind to the target receptor on intestinal epithelial cell cultures. The Zot biologically active domain was localized toward the carboxyl terminus of the protein and coincided with the predicted cleavage product generated by V. cholerae. This domain shared a putative receptor-binding motif with zonulin, the Zot mammalian analogue involved in tight junction modulation. Amino acid comparison between the Zot active fragment and zonulin, combined with site-directed mutagenesis experiments, confirmed the presence of an octapeptide receptor-binding domain toward the amino terminus of the processed Zot.
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Lu R, Hu CP, Peng J, Deng HW, Li YJ. Role of calcitonin gene-related peptide in ischaemic preconditioning in diabetic rat hearts. Clin Exp Pharmacol Physiol 2001; 28:392-6. [PMID: 11380512 DOI: 10.1046/j.1440-1681.2001.03467.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. It has been suggested that calcitonin gene-related peptide (CGRP) is involved in the protection provided by ischaemic preconditioning in rat hearts and that ischaemic preconditioning is absent in diabetic rat hearts. 2. In the present study, we tested the relationship between sensory nerve function and ischaemic preconditioning in diabetic rats. 3. In 4- and 8-week diabetic rats and age-matched non- diabetic controls, 30 min global ischaemia and 40 min reperfusion caused a significant decrease in cardiac function and a marked increase in creatine kinase (CK) release. Ischaemic preconditioning, by three cycles of 5 min ischaemia and 5 min reperfusion, improved the recovery of cardiac function and decreased CK release during reperfusion in 4-week diabetic rat hearts. However, the cardioprotection afforded by ischaemic preconditioning was lost in 8-week diabetic rat hearts. Pretreatment with CGRP for 5 min also significantly improved the recovery of cardiac function and decreased CK release in rats subjected to 4 or 8 weeks of diabetes. 4. The content of CGRP in the coronary effluent during ischaemic preconditioning was significantly increased in 4-week diabetic rat hearts (P < 0.05). However, only a slight increase in the release of CGRP was shown in 8-week diabetic rat hearts (P > 0.05). 5. In summary, the present results suggest that the protection afforded by ischaemic preconditioning is attenuated in diabetic rats and that the change may be related to the reduction in CGRP release in diabetic rat hearts.
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Fujiwara S, Takeo N, Otani Y, Parry DA, Kunimatsu M, Lu R, Sasaki M, Matsuo N, Khaleduzzaman M, Yoshioka H. Epiplakin, a novel member of the Plakin family originally identified as a 450-kDa human epidermal autoantigen. Structure and tissue localization. J Biol Chem 2001; 276:13340-7. [PMID: 11278896 DOI: 10.1074/jbc.m011386200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 450-kDa human epidermal autoantigen was originally identified as a protein that reacted with the serum from an individual with a subepidermal blistering disease. Molecular cloning of this protein has now shown that it contains 5065 amino acids and has a molecular mass of 552 kDa. As reported previously this protein, which we call epiplakin, belongs to the plakin family, but it has some very unusual features. Epiplakin has 13 domains that are homologous to the B domain in the COOH-terminal region of desmoplakin. The last five of these B domains, together with their associated linker regions, are particularly strongly conserved. However, epiplakin lacks a coiled-coil rod domain and an amino-terminal domain, both of which are found in all other known members of the plakin family. Furthermore, no dimerization motif was found in the sequence. Thus, it is likely that epiplakin exists in vivo as a single-chain structure. Epitope mapping experiments showed that the original patient's serum recognized a sequence unique to epiplakin, which was not found in plectin. Immunofluorescence staining revealed the presence of epiplakin in whole sheets of epidermis and esophagus, in glandular cells of eccrine sweat and parotid glands and in mucous epithelial cells in the stomach and colon.
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Qiu Z, Guo P, Wang J, Lu R, Qiu H, Li X, Zhu J. [Single particle source apportionment of atmospheric aerosol based on proton microprobe]. HUAN JING KE XUE= HUANJING KEXUE 2001; 22:51-4. [PMID: 11432067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
A proton microprobe with high resolution and high sensitivity was applied to analyze atmospheric aerosol in the people's park in Shanghai urban for single particle source apportionment. The results showed that the sum of the average contribution rates from the sources of soil dust, building construction dust, vehicle exhaust and metallurgical industry, which are the main pollution sources of atmospheric aerosol in Shanghai urban and surpasses 80%. Besides, about 13% of the particles could not be identified. On the basis of cluster analysis of these particles, they are preliminary known belonging to two different individual sub-pollution sources and a new unidentified pollution source.
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Abstract
BACKGROUND Glutamine has been shown to be an important dietary component for the maintenance of gut integrity. Although considered a nonessential amino acid in normal circumstances, glutamine may become conditionally essential for the bowel during episodes of severe illness and malnutrition. In this study, we employed an animal model simulating mechanical intestinal obstruction to explore the beneficial effects of glutamine on the intestine in response to obstruction-induced injury. MATERIALS AND METHODS Rats were on three feeding regimens-standard diet and water (control group), diet and water containing 2% glutamine (glutamine group), or diet and water containing 2% arginine (arginine group)-for 3 days prior to surgical preparation of intestinal obstruction. The bowel distension, fluid accumulation, and histological alterations in the intestinal mucosa were measured 40 h after ileal ligation. RESULTS After 3 days of drinking water intervention, the plasma glutamine levels in the glutamine group (677 +/- 12 microM) were higher than those in the control (451 +/- 27 microM) and arginine (379 +/- 25 microM) groups. The distension ratio measured 40 h after ileal ligation was significantly lower in the glutamine group (30.9 +/- 4.2%) than in the control and arginine groups (45.9 +/- 1.7 and 46.1 +/- 3.4%, respectively). Also, glutamine markedly decreased the fluid accumulation in the obstructed bowel segment (control group, 178.41 +/- 18.60 mg/cm; glutamine group, 104.97 +/- 13.17 mg/cm; arginine group, 141.4 +/- 12.85 mg/cm). Furthermore, the obstruction-induced mucosal injury was substantially improved in glutamine-fed rats. CONCLUSIONS Our findings indicate that glutamine can significantly reduce the degree of those physiological derangements induced by mechanical intestinal obstruction.
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Wang ZF, Peng ZY, Huang LJ, Lu R, Tian GY. [Physico-chemical properties and biological activities of a glycoconjugate SPPA-1 from Spirulina platensis]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2001; 36:112-5. [PMID: 12579876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To isolate polysaccharide from Spirulina platensis and determine its sugar position, molecular weight and biological activities. METHODS Sephadex G-75 and CM-Sephadex C-50 were used. The sugar position was analyzed by gas chromatography, the molecular weight was determined by GPC. The homogeneity of this glycoconjugate was determined by HPLC and CE. IR and NMR spectra were used to determine the glycosidic linkage. RESULTS SPPA-1 was a homogeneous glycoconjugate, its carbohydrate chain was composed of alpha-glucopyranan, carbohydrate content is 91.70%, Nitrogen content was 0.96%, the molecular weight was 69.00 x 10(4), SPPA-1 could eliminate O2-. radicals. CONCLUSION SPPA-1 was an antioxidative glycoconjugate from Spirulina platensis.
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Lu R, Serrero G. Mediation of estrogen mitogenic effect in human breast cancer MCF-7 cells by PC-cell-derived growth factor (PCDGF/granulin precursor). Proc Natl Acad Sci U S A 2001; 98:142-7. [PMID: 11134521 PMCID: PMC14558 DOI: 10.1073/pnas.98.1.142] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PC-cell-derived growth factor (PCDGF) is an 88-kDa glycoprotein corresponding to the granulin precursor. We have reported that PCDGF was expressed in human breast cancer cells. In estrogen-receptor positive cells, 17-beta-estradiol (E(2)) transcriptionally stimulated PCDGF expression in a dose- and time-dependent fashion. We demonstrate here that PCDGF mediates the mitogenic effect of E(2) in MCF-7 cells. PCDGF substituted for E(2) to stimulate DNA synthesis. The E(2) mitogenic effect was inhibited in a dose-dependent fashion by anti-PCDGF neutralizing antibody. Inhibition of PCDGF expression by antisense transfection also inhibited the E(2) mitogenic effect. In contrast, overexpression of PCDGF in MCF-7 cells resulted in cells that were able to proliferate in the absence of estrogen and were tamoxifen resistant. The PCDGF signaling pathway was examined. Like E(2), PCDGF stimulated mitogen-activated protein kinase activity. PCDGF could substitute for E(2) in stimulating cyclin D1 expression. The cyclin D1 stimulation by E(2) was 50% inhibited by anti-PCDGF antibody. In contrast, PCDGF did not stimulate c-myc expression, another molecular target of E(2). We conclude that autocrine PCDGF mediates the E(2) mitogenic effect via stimulation of cyclin D1. These studies provide information on estrogen action and identify an autocrine molecular target in human breast cancer cells.
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Uzzau S, Lu R, Wang W, Fiore C, Fasano A. Purification and preliminary characterization of the zonula occludens toxin receptor from human (CaCo2) and murine (IEC6) intestinal cell lines. FEMS Microbiol Lett 2001; 194:1-5. [PMID: 11150657 DOI: 10.1111/j.1574-6968.2001.tb09437.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
In the present study, we report the preliminary characterization of the epithelial cell receptor for Vibrio cholerae zonula occludens toxin (Zot). Zot receptor was purified by ligand-affinity chromatography. Analysis of affinity-purified preparations by polyacrylamide gel electrophoresis revealed a protein of ca. 66 kDa. Partial N-terminal sequence obtained from purified murine and human Zot receptor revealed homology between the two proteins and with human alpha-1-chimaerin. Zot protein domain(s) involved in receptor binding were also analyzed by constructing several in frame deletion derivatives of a recombinant fusion Zot protein tagged with maltose binding protein. Our results suggest that Zot binding to its cellular membrane receptor requires a sequence that spans between amino acids 118 and 299.
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Qiu J, Ogus S, Lu R, Chehab FF. Transgenic mice overexpressing leptin accumulate adipose mass at an older, but not younger, age. Endocrinology 2001; 142:348-58. [PMID: 11145598 DOI: 10.1210/endo.142.1.7909] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sensitivity to leptin is associated with a normal regulation of the adipose mass, whereas decreased leptin sensitivity results in elevated adipose tissue stores. To address whether the effects of chronic hyperleptinemia are sustained with age, we generated transgenic mice that overexpress leptin under the control of the fat specific aP2 promoter/enhancer. At 6-9 weeks of age, transgenic mice overexpressed 5-fold more human leptin than endogenous mouse levels and had consistently low body weights, with reduced brown and white fat depots characterized by adipocytes either devoid of or containing minute lipid droplets. However, at 33-37 weeks, despite continuous secretion of human leptin, the transgenic mice showed a rebound effect characterized by an increase in body weight, accumulation of adipose mass, and lipid-filled adipocytes. Thus, this mouse model exhibits a two-stage phenotype, with respect to fat accumulation. In addition, plasma glucose, triglycerides, and cholesterol levels were markedly depressed in young, but not older, transgenic mice. A detrimental consequence of early hyperleptinemia was a failure of the transgenic mice to acclimatize to the cold, as a result of depleted fat stores within their brown adipocytes. Cold exposure was tolerated after a 2-week high-fat diet or at an older age when fat depots had naturally accumulated. Treatment of the older transgenic mice with large doses of leptin stimulated weight loss, demonstrating that the leptin pathway still responds to pharmacological levels of leptin. Overall, these studies show that moderate hyperleptinemia in normal mice results in a sensitivity of the adipose mass to leptin at a younger (but not older) age. The mechanisms that lead to the accumulation of fat at an older age remain largely unknown, and this hyperleptinemic mouse model will allow the uncovering of at least some of these mechanisms.
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Su H, Lu R, Kan YW. Adeno-associated viral vector-mediated vascular endothelial growth factor gene transfer induces neovascular formation in ischemic heart. Proc Natl Acad Sci U S A 2000; 97:13801-6. [PMID: 11095751 PMCID: PMC17656 DOI: 10.1073/pnas.250488097] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) plays important roles in physiological and pathological angiogenesis. Recent studies have demonstrated that direct injection of VEGF protein, plasmid DNA, or an adenoviral vector encoding the VEGF gene into ischemic myocardium or limb can induce collateral blood vessel formation and improve perfusion of the ischemic areas. However, these approaches have limitations ranging from a short-lasting effect to angioma formation. In this study, we investigated the feasibility of using adeno-associated viral (AAV) vectors to deliver VEGF genes to mouse myocardium. A cytomegalovirus promoter was used to drive genes for a human VEGF isoform, VEGF(165), and LacZ. A mouse myocardial ischemic model was generated by ligation of the anterior descending coronary artery. Approximately 10(11) copies of the AAV-VEGF vector mixed with 10(10) copies of AAV-LacZ were injected to one site of normal myocardium and a total of 10(11) copies of AAV-VEGF were injected to multiple sites of myocardium around the ischemic region. LacZ gene expression was observed up to 3 months after the vector inoculation. After AAV-VEGF inoculation, neoangiogenesis was observed in the ischemic heart model but not in normal heart tissue. An inflammatory-cell infiltration was not observed in the AAV-VEGF- and AAV-LacZ-inoculated hearts, and angioma-like structure was not observed. These results indicated that injection of the AAV vector directly to myocardium could mediate efficient gene transfer and transgene expression and that VEGF gene delivered by AAV vector can induce angiogenesis in ischemic myocardium.
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Yuan Y, Qin Q, Lu R. [Design and implementation of a landscape analysis system based on remote sensing data]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2000; 11:927-30. [PMID: 11767574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Because of the functions of Geographic Information System(GIS) being not satisfied to the requirements of landscape analysis, a landscape analysis system was designed with Visual C++ and demonstrated with remote sensing data. This system adopted the method f picking-up patch boundary pixel set, improved the patch searching speed, and supplied some landscape analysis functions, such as the calculation of the distance between patches, and the boundary length of neighboring patch, which are not provided by current GIS. It was used to analyzed the landscape of suburbs in northwest Beijing, and the shortcomings of current GIS applied in landscape analysis were overcome.
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Li N, Lu R, Tang Y, Yuan Z, Han T, Zhang S. [CT guided percutaneous fine needle aspiration for early diagnosis of pancreatic infection after acute necrotizing pancreatitis]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2000; 38:895-6. [PMID: 11832189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To assess CT-guided percutaneous fine needle aspiration (FNA) for early diagnosis of pancreatic infection after acute necrotizing pancreatitis. METHODS CT-guided percutaneous FNA was employed to diagnose pancreatic infection after acute necrotizing pancreatitis in 14 patients. The aspirates were smeared, cultured and subjected polymerase to chain reaction (PCR) for detecting bacteria. RESULTS Ten patients were diagnosed as having pancreatic infection and 4 non-pancreatic infection. FNA was totally performed for 15 times: left retroperitoneal route for 12 times, left and right retroperitoneal route for one time, and transperitoneal route for two times. The sensitivity of smear, PCR, culture to diagnose pancreatic infection was 7/10, 9/10, 10/10, respectively. Their specificity was 4/4, and the time for obtaining the results was 30 minutes, 4 hours, 3 days respectively. CONCLUSIONS Retroperitoneal approach can be used for most patients with acute necrotizing pancreatitis when performing CT guided-percutaneous FNA. PCR of aspirates is a rapid and accurate method to diagnose pancreatic infection.
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Lu R, Liu J, Zhang J, Zheng H, Yuan Z, Lin J. [The histological changes after preserved human amniotic membrane transplantation for conjunctival reconstruction of rabbits eyes]. YAN KE XUE BAO = EYE SCIENCE 2000; 16:224-7. [PMID: 12579774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
PURPOSE To investigate the histological changes after preserved human amnotic membrane transplantation of rabbit eyes. METHODS The conjunctiva of 12 New Zealand albino rabbits' right eyes were excised partly. Then the preserved human amniotic membrane were transplanted on the sclera. Eyes were enucleated at 1 week, 3 weeks, 5 weeks and 12 weeks (n = 3 for each) after surgery, and they were examined histologically with staining of HE, PAS, and transmission electronic microscopy. RESULTS At 1 week after transplantation, the human amniotic membrane firmly attached on the sclera, with the dead epithelial cells remaining on its surface. At 3 weeks, conjunctival epithelization was completed on the human amniotic membrane. Abundant PAS-positive goblet cells were recognized. The amnion began resolve. At 12 weeks, the amnion dissolved. On transmission electronic microscopy, the cell polarity is prominent. The epithelial cells contained a large number of mitochondria and endoplasmic reticulum. Microvilli were pronounced on the apical cell membrane. There are many intracellular desmosomes and hemidesmosomes. CONCLUSION Preserved human amniotic membrane is a valuable conjunctival replacement material. After transplantation, the histology of new tissue is as same as normal conjunctive.
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Lu R, Koenderink JJ, Kappers AM. Optical properties (bidirectional reflectance distribution function) of shot fabric. APPLIED OPTICS 2000; 39:5785-5795. [PMID: 18354579 DOI: 10.1364/ao.39.005785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
To study the optical properties of materials, one needs a complete set of the angular distribution functions of surface scattering from the materials. Here we present a convenient method for collecting a large set of bidirectional reflectance distribution function (BRDF) samples in the hemispherical scattering space. Material samples are wrapped around a right-circular cylinder and irradiated by a parallel light source, and the scattered radiance is collected by a digital camera. We tilted the cylinder around its center to collect the BRDF samples outside the plane of incidence. This method can be used with materials that have isotropic and anisotropic scattering properties. We demonstrate this method in a detailed investigation of shot fabrics. The warps and the fillings of shot fabrics are dyed different colors so that the fabric appears to change color at different viewing angles. These color-changing characteristics are found to be related to the physical and geometrical structure of shot fabric. Our study reveals that the color-changing property of shot fabrics is due mainly to an occlusion effect.
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Lu R, Au WC, Yeow WS, Hageman N, Pitha PM. Regulation of the promoter activity of interferon regulatory factor-7 gene. Activation by interferon snd silencing by hypermethylation. J Biol Chem 2000; 275:31805-12. [PMID: 10924517 DOI: 10.1074/jbc.m005288200] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The molecular mechanism by which virus induces expression of the early inflammatory genes has not yet been completely elucidated. Previous studies indicated that the virus-mediated transcription of type I interferon (IFN) genes required activation of two members of IFN regulatory factor (IRF) family, IRF-3 and IRF-7, where the expression of IRF-7 was found to be indispensable for the induction of IFNA genes. To determine the factors that regulate expression of IRF-7 gene, as well as its inducibility by type I IFNs, we have isolated and characterized the promoter and first intron of the human IRF-7 gene. This region shows a presence of two potential interferon-sensitive response elements (ISRE/IRF-E). However, only the ISRE present in the first intron was functional and conferred interferon inducibility in a transient transfection assay. Using a pull-down assay with an oligodeoxynucleotide corresponding to this ISRE immobilized to magnetic beads, we have demonstrated that this ISRE binds ISGF3 complex and IRF-1 from the extract of IFN-treated cells but not from the untreated cells. We have further shown that the previously observed lack of expression of IRF-7 in 2fTGH fibrosarcoma cell line, correlated with hypermethylation of the CpG island in the human IRF-7 promoter. The repression of the promoter activity was relieved by treatment with DNA methyltransferase inhibitor 5-aza-deoxycytidine. In vitro methylation of IRF-7 promoter silenced IRF-7 directed expression of luciferase gene in HeLa cells that express endogenous IRF-7 gene. Whether silencing of IRF-7 by methylation is instrumental for the process of tumorigenesis remains to be determined.
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