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Biomedical subjects

Q Li

Publications and source records attributed to Q Li.

At least 19 recordsLinked to original sources
PubMed2007

Murine dendritic cells modified with CXCL10 gene and tumour cell lysate mediate potent antitumour immune responses in mice.

The aim of our present study was to estimate the effect of a therapeutic vaccine against tumour based on dendritic cells (DC) vaccine modified with tumour cell lysate and chemokine CXCL10 gene. In this study, mouse bone marrow DC were pulsed with tumour cell (RM-1) lysate and then transfected with a plasmid vector expressing CXCL10 cDNA by DOTAP liposome. The protective and therapeutic effects of the DC vaccine in RM-1 tumour model were assessed (divided into CXCL10/Lysate-DC, CXCL10/DC, pcDNA/Lysate-DC, Lysate-DC, pcDNA-DC, DC and PBS). The DC transfected with CXCL10 gene were capable of synthesizing and secreting CXCL10 chemokine. The highest CTL activity against RM-1 cells was induced in mice immunized with DC vaccine that was modified with RM-1 lysate and CXCL10 gene (CXCL10/Lysate-DC) when compared with its counterpart in mice. The CXCL10/Lysate-DC immunized mice also exhibited resistance to tumour challenge most effectively. In the RM-1 tumour model, immunization of CXCL10/Lysate-DC inhibited the tumour growth most significantly when compared with other groups and the survival time of the mice treated with CXCL10/Lysate-DC was greatly extended. These findings provide a potential strategy to improve the efficacy of DC-based tumour vaccine.

Animals↗
PubMed2007

Antimicrobial resistance of Listeria spp. recovered from processed bison.

AIMS: The current study examined the antimicrobial susceptibility of 86 Listeria spp. isolated from processed bison carcasses. MATERIALS AND METHODS: Susceptibility to 25 antimicrobial agents was determined using E-test and National Antimicrobial Resistance Monitoring System (NARMS) panels. Most Listeria isolates (88-98%) exhibited resistance to bacitracin, oxacillin, cefotaxime, and fosfomycin. Resistance to tetracycline (18.6%) was also common. Of the 16 tetracycline-resistant Listeria isolates, 15 carried tetM and 2 contained integrase of Tn1545 transposons. Rifampicin and trimethoprim-sulfamethoxazole were the most active antimicrobial agents against Listeria spp., with a MIC(90) of 0.38 microg ml(-1). Ampicillin, erythromycin, penicillin, gentamicin, and tobramycin also exhibited good activity against Listeria spp., with MIC(90) not exceeding 1 microg ml(-1). Differences in resistance among Listeria spp. was displayed, as Listeria innocua strains were more resistant than other Listeria species. CONCLUSIONS: The study showed that Listeria monocytogenes strains from bison were susceptible to the antibiotics most commonly used to treat human listeriosis. However, the presence of antimicrobial resistance in L. innocua indicates the potential for transfer of resistance and a conjugative transposon to L. monocytogenes. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of our study will provide useful information for the development of public health policy in the use of antimicrobials in food animal production.

Animals↗
PubMed2006

Bismuth telluride (Bi2Te3) nanowires: synthesis by cyclic electrodeposition/stripping, thinning by electrooxidation, and electrical power generation.

Nanowires composed of the thermoelectric material Bi2Te3 were synthesized on highly oriented pyrolytic graphite (HOPG) electrodes using the electrochemical step edge decoration (ESED) method. Nanowire synthesis was initiated by applying a voltage pulse of -0.75 V versus SCE for 5 ms to an HOPG electrode in an aqueous solution containing both Bi3+ and TeO22-, thereby producing nuclei at the step edges. Bi2Te3 was electrodeposited onto these nuclei using a cyclic electrodeposition-stripping scheme that involved the electrodeposition of bismuth-rich Bi2Te3 on a negative-going voltammetric scan (to -0.05 V) and the subsequent anodic stripping of excess bismuth from these nanowires during a positive-going scan (to +0.35 V). When this cycle was repeated 10-50 times, Bi2Te3 nanowires in the 100-300-nm-diameter range were obtained. These nanowires were narrowly dispersed in diameter (RSDdia = 10-20%), were more than 100 microm in length, and were organized into parallel arrays containing hundreds of wires. Smaller nanowires, with diameters down to 30 nm, were obtained by electrooxidizing 150-nm-diameter Bi2Te3 nanowires at +0.37 V under conditions of kinetic control. This oxidation process unexpectedly improved the uniformity of Bi2Te3 nanowires, and X-ray photoelectron spectroscopy (XPS) shows that these nanowires retain a Bi2Te3 core but also have a thin surface layer composed of Bi and Te oxides. The ability of Bi2Te3 nanowires to generate electrical power was assessed by transferring ensembles of these nanowires onto cyanoacrylate-coated glass surfaces and evaporating 4-point nickel contacts. A dimensionless figure of merit, ZT, ranging from 0 to 0.85 was measured for fresh samples that were less than 1 day old. XPS reveals that Bi2Te3 nanowires are oxidized within a week to Bi2O3 and TeO2. These oxides may interfere with the application by evaporation of electrical contacts to these nanowires.

Alloys↗
PubMed2006

Amyloid-beta vaccination, but not nitro-nonsteroidal anti-inflammatory drug treatment, increases vascular amyloid and microhemorrhage while both reduce parenchymal amyloid.

Vaccination with Abeta(1-42) and treatment with NCX-2216, a novel nitric oxide releasing flurbiprofen derivative, have each been shown separately to reduce amyloid deposition in transgenic mice and have been suggested as potential therapies for Alzheimer's disease. In the current study we treated doubly transgenic amyloid precursor protein and presenilin-1 (APP+PS1) mice with Abeta(1-42) vaccination, NCX-2216 or both drugs simultaneously for 9 months. We found that all treatments reduced amyloid deposition, both compact and diffuse, to the same extent while only vaccinated animals, with or without nonsteroidal anti-inflammatory drug (NSAID) treatment, showed increased microglial activation associated with the remaining amyloid deposits. We also found that active Abeta vaccination resulted in significantly increased cerebral amyloid angiopathy and associated microhemorrhages, while NCX-2216 did not, in spite of similar reductions in parenchymal amyloid. Co-administration of NCX-2216 did not attenuate this effect of the vaccine. This is the first report showing that active immunization can result in increased vascular amyloid and microhemorrhage, as has been observed with passive immunization. Co-administration of an NSAID agent with Abeta vaccination does not substantially modify the effects of Abeta immunotherapy. The difference between these treatments with respect to vascular amyloid development may reflect the clearance-promoting actions of the vaccine as opposed to the production-modifying effects proposed for flurbiprofen.

Alzheimer Disease↗
PubMed2006

Modelling of fracture behaviour in biomaterials.

One of the most frequent causes of degradation and failure of quasi-brittle biomaterials is fracture. Mechanical breakdown, even when not catastrophic, is of particular importance in the area of biomaterials, as there are many clinical situations where it opens the path for biologically mediated failures. Over the past few decades the materials/biomaterials community has developed a number of numerical models, but only with limited incorporation of brittle failure phenomena. This article investigates the ability of a non-linear elastic fracture mechanics (NLEFM) model to reliably predict failure of biomaterials with a specific focus on the clinical settings of restorative dentistry. The approach enables one to predict fracture initiation and propagation in a complex biomechanical status based on the intrinsic material properties of the components. In this paper, we consider five examples illustrating the versatility of the present approach, which range from the failure of natural biomaterials, namely dentine and enamel, to a restored tooth, a three unit all ceramic bridge structure and contact-induced damage in the restorative layered materials systems. It is anticipated that this approach will have ramifications not only to model fracture events but also for the design and optimisation of the mechanical properties of biomaterials for specific clinically determined requirements.

Biocompatible Materials↗
PubMed2006

Charge order, metallic behavior, and superconductivity in La2-xBaxCuO4 with x=1/8.

The ab-plane optical properties of a cleaved single crystal of La2-xBaxCuO4 for x=1/8 (Tc approximately =2.4 K) have been measured over a wide frequency and temperature range. The low-frequency conductivity is Drude-like and shows a metallic response with decreasing temperature. However, below approximately =60 K, corresponding to the onset of charge-stripe order, there is a rapid loss of spectral weight below about 40 meV. The behavior is quite different from that typically associated with the pseudogap in the normal state of the cuprates. Instead, the gapping of the normal-state single-particle excitations looks surprisingly similar to that observed in superconducting La2-xSrxCuO4, including the presence of a residual Drude peak with reduced weight.

Journal Article↗
PubMed2006

Cloning and molecular characterization of three novel LMW-i glutenin subunit genes from cultivated einkorn (Triticum monococcum L.).

Three novel low molecular weight (LMW) glutenin subunits from cultivated einkorn (Triticum monococcum L., A(m)A(m), 2n = 2x = 14) were characterized by SDS-PAGE and molecular weights determined by MALDI-TOF-MS. Their coding genes were amplified and cloned with designed AS-PCR primers, revealing three complete gene sequences. All comprised upstream, open reading frame (ORF), downstream and no introns were present. The deduced amino acid sequences showed that all three genes, named as LMW-M1, LMW-M3 and LMW-M5, respectively, belonged to the LMW-i type subunits with the predicted molecular weight between 38.5206 and 38.7028 kDa. They showed high similarity with other LMW-i type genes from hexaploid bread wheats, but also displayed unique features. Particularly, LMW-M5 subunit contained an extra cysteine residue in the C-terminus except for eight conserved cysteines, which resulted from a single-nucleotide polymorphism (SNP) of the T-C transition, namely arginine --> cysteine substitution at position 242 from the N-terminal end. This is the first report that the LMW-i subunit contained nine cysteines residues that could result in a more highly cross-linked and more elastic glutenin suggesting that LMW-M5 gene may associates with good quality properties. In addition, a total of 25 SNPs and one insertions/deletions (InDels) were detected among three LMW-i genes, which could result in significant functional changes in polymer formation of gluten. It is anticipated that these SNPs could be used as reliable genetic markers during wheat quality improvement. The phylogenetic analysis indicated that LMW-i type genes apparently differed from LMW-m and LMW-s type genes and diverged early from the primitive LMW-GS gene family, at about 12.92 million years ago (MYA) while the differentiation of A(m) and A genomes was estimated at 3.98 MYA.

Amino Acid Sequence↗
PubMed2006

N type Ca2+ channels and RIM scaffold protein covary at the presynaptic transmitter release face but are components of independent protein complexes.

Fast neurotransmitter release at presynaptic terminals occurs at specialized transmitter release sites where docked secretory vesicles are triggered to fuse with the membrane by the influx of Ca2+ ions that enter through local N type (CaV2.2) calcium channels. Thus, neurosecretion involves two key processes: the docking of vesicles at the transmitter release site, a process that involves the scaffold protein RIM (Rab3A interacting molecule) and its binding partner Munc-13, and the subsequent gating of vesicle fusion by activation of the Ca2+ channels. It is not known, however, whether the vesicle fusion complex with its attached Ca2+ channels and the vesicle docking complex are parts of a single multifunctional entity. The Ca2+ channel itself and RIM were used as markers for these two elements to address this question. We carried out immunostaining at the giant calyx-type synapse of the chick ciliary ganglion to localize the proteins at a native, undisturbed presynaptic nerve terminal. Quantitative immunostaining (intensity correlation analysis/intensity correlation quotient method) was used to test the relationship between these two proteins at the nerve terminal transmitter release face. The staining intensities for CaV2.2 and RIM covary strongly, consistent with the expectation that they are both components of the transmitter release sites. We then used immunoprecipitation to test if these proteins are also parts of a common molecular complex. However, precipitation of CaV2.2 failed to capture either RIM or Munc-13, a RIM binding partner. These findings indicate that although the vesicle fusion and the vesicle docking mechanisms coexist at the transmitter release face they are not parts of a common stable complex.

Animals↗
PubMed2006

Formation of C=C and Si-Cl adstructures by insertion reactions of cis-dichloroethylene and perchloroethylene on Si(100)2 x 1.

The room-temperature adsorption and thermal evolution of cis-dichloroethylene (DCE) and perchloroethylene (PCE) on Si(100)2 x 1 have been studied by X-ray photoelectron spectroscopy and temperature programmed desorption (TPD) mass spectrometry. Unlike ethylene that is found to adsorb on Si(100)2 x 1 through a [2+2] cycloaddition reaction, cis-DCE and PCE appear to dechlorinate upon adsorption on the 2 x 1 surface through an insertion reaction preserving the C=C bond. Our C 1s XPS spectra are consistent with the existence of mono-sigma-bonded and di-sigma bonded dechlorinated adstructures for both cis-DCE and PCE. The presence of the XPS C 1s feature at 283.9 eV, characteristic of the (=C<(Si)(Si)) component, supports the formation of a unique tetra-sigma-bonded C(2) dimer (i.e., by full dechlorination) for PCE, which is found to be stable to 800 K. In marked contrast to PCE for which no organic desorption fragments are observed, m/z 26 TPD features at 590 and 750 K have been observed for cis-DCE. These features could be attributed to the formation of acetylene resulting from Cl beta-elimination of 2-chlorovinyl adspecies and to direct desorption of vinylene, respectively. Further annealing the cis-DCE and PCE samples to above 800 K produces SiC and/or carbon clusters. The TPD data also show HCl evolution over 810-850 K for both cis-DCE and PCE, the latter of which also exhibits an additional SiCl(2) evolution above 850 K. The present work illustrates that the insertion mechanism could be quite common in the surface chemistry of chlorinated ethylenes on the 2 x 1 surface.

Journal Article↗
PubMed2006

RNAi-based screening of the human kinome identifies Akt-cooperating kinases: a new approach to designing efficacious multitargeted kinase inhibitors.

Tumors comprise genetically heterogeneous cell populations, whose growth and survival depend on multiple signaling pathways. This has spurred the development of multitargeted therapies, including small molecules that can inhibit multiple kinases. A major challenge in designing such molecules is to determine which kinases to inhibit in each cancer to maximize efficacy and therapeutic index. We describe an approach to this problem implementing RNA interference technology. In order to identify Akt-cooperating kinases, we screened a library of kinase-directed small interfering RNAs (siRNAs) for enhanced cancer cell killing in the presence of Akt inhibitor A-443654. siRNAs targeting casein kinase I gamma 3 (CSNK1G3) or the inositol polyphosphate multikinase (IPMK) significantly enhanced A-443654-mediated cell killing, and caused decreases in Akt Ser-473 and ribosomal protein S6 phosphorylation. Small molecules targeting CSNK1G3 and/or IPMK in addition to Akt may thus exhibit increased efficacy and have the potential for improved therapeutic index.

Antineoplastic Agents↗
PubMed2006

Adrenoceptor blockade alters plasma gelatinase activity in patients with heart failure and MMP-9 promoter activity in a human cell line (ECV304).

This study assessed the effects of short-term adrenoceptor blockade on plasma matrix metalloproteinase (MMP) activity in patients with heart failure, and the ability of adrenoceptor stimulation to modulate matrix metalloproteinase-9 (MMP-9) promoter activity in vitro. Patients with heart failure received standard therapy or standard therapy plus carvedilol. Plasma MMP activity was determined by zymography and tissue inhibitor (TIMP-1) expression was measured by immunoblotting. MMP-9 promoter activity was assessed in transfected ECV304 cells following exposure to isoprenaline or phenylephrine in the absence or presence of either propranolol or prazosin. In patients with heart failure, carvedilol attenuated the increase in proMMP-9 activity observed at 4 and 12 weeks in non-beta-blocker-treated patients (44.0 +/- 4.9 AU versus 60.8 +/- 6.7 AU; P < 0.05). Although TIMP-1 expression was unaltered, the MMP-9:TIMP-1 ratio was lower in those receiving carvedilol at 4 and 12 weeks (0.54 +/- 0.07 versus 1.04 +/- 0.17; P < 0.05). Isoprenaline transiently increased MMP-9 promoter activity after 4 h exposure (80.6 +/- 14.8-fold; P < 0.001) before returning to baseline. The response to isoprenaline was prevented by propranolol (P < 0.01). Phenylephrine caused a biphasic increase in MMP-9 promoter activity, with the greatest increase occurring at 24 h (23 +/- 3.7-fold) compared to baseline. This response was unaffected by co-incubation with prazosin. In conclusion, treatment with a mixed alpha1/beta-adrenoceptor antagonist attenuates MMP activity and tips the degradative balance to a less degradative phenotype in heart failure patients. Furthermore, adrenoceptor stimulation increases MMP-9 promoter activity, which is inhibited by beta- but not alpha-adrenoceptor blockade. Therefore, mixed adrenoceptor blockade may reduce remodeling in heart failure as a direct consequence of a beta-adrenoceptor-mediated reduction in MMP-9 transcription.

Adrenergic alpha-Antagonists↗
PubMed2006

Long splice variant N type calcium channels are clustered at presynaptic transmitter release sites without modular adaptor proteins.

The presynaptic N type Ca channel (CaV2.2) is associated with the transmitter release site apparatus and plays a critical role in the gating of transmitter release. It has been suggested that a distinct CaV2.2 long C terminal splice variant is targeted to the nerve terminal and is anchored at the release face by calcium/calmodulin-dependent serine protein kinase (CASK) and Munc-18-interacting protein (MINT), two modular adaptor proteins. We used the isolated chick ciliary ganglion calyx terminal together with two new antibodies (L4569, L4570) selective for CaV2.2 long C terminal splice variant to test these hypotheses. CaV2.2 long C terminal splice variant was present at the presynaptic transmitter release sites, as identified by Rab3a-interacting molecule (RIM) co-staining and quantitative immunocytochemistry. CASK was also present at the terminal both in conjunction with, and independent of its binding partner, MINT. Immunoprecipitation of CaV2.2 long C terminal splice variant from brain lysate coprecipitated CASK, confirming that these two proteins can form a complex. However, CASK was not colocalized either with CaV2.2 long C terminal splice variant or the transmitter release site marker RIM at the calyx terminal release face. Neither was MINT colocalized with CaV2.2 long C terminal splice variant. Our results show that native CaV2.2 long C terminal splice variant is targeted to the transmitter release sites at an intact presynaptic terminal. However, the lack of enrichment of CASK at the release site combined with the failure of this protein or its partner MINT to colocalize with CaV2.2 argues against the idea that these modular adaptor proteins anchor CaV2.2 at presynaptic nerve terminals.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Relationship of p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancers with comedonecrosis as an accelerated apoptosis.

AIMS: To study the relationship between comedonecrosis formation and morphology, apoptosis, and p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancer. EXPERIMENTAL DESIGN: Early invasive breast cancers were first divided into two groups according to the presence (CN+ tumours) or absence (CN- tumours) of comedonecrosis. The histological grade, apoptosis, and expression of E-cadherin, Ki-67, p53 and Bcl-2 in the cancer-affected area, and in normal ducts from the specimen, were then examined. RESULTS: Less tubule and gland formation was seen in CN+ tumours than in CN- tumours, although the histological grade between the groups was not different. During early comedonecrosis, cells undergo apoptosis and subsequent necrosis. p53 was higher in CN+ tumours than in CN- tumours and normal ducts, whereas Bcl-2 was lower in CN+ tumours than in CN- tumours and normal ducts. Both tumours had higher Ki-67 than in normal ducts, but no difference was evident between the tumours. CN+ tumours had slightly higher E-cadherin than that in CN- tumours, but lower than that in normal ducts. The level of comedonecrosis was positively correlated with p53, but inversely correlated with Bcl-2 in all tumours, and p53 and Bcl-2 were inversely correlated with each other. Furthermore, comedonecrosis and p53 were correlated with Ki-67 in CN+ tumours, and Bcl-2 was correlated with Ki-67 in CN- tumours. CONCLUSION: Comedonecrosis may be actively regulated through an apoptotic procedure in massive cancers for their survival and progression, and the above proteins may be associated cooperatively in this process. CN+ and CN- tumours may have opposite proliferative systems under the p53-Bcl-2 pathway.

Apoptosis↗
PubMed2006

Mechanism of neuroprotective effect induced by QingKaiLing as an adjuvant drug in rabbits with E. coli bacterial meningitis.

OBJECTIVE: To explore the neuroprotective effects and underlying mechanism of QingKaiLing (QKL) as an adjuvant treatment for bacterial meningitis. METHOD: E. coli bacterial meningitis rabbits were treated with antibiotics (ampicillin) alone or in combination with QKL. The number of leukocytes and the concentration of protein in the cerebrospinal fluid (CSF) of rabbits were determined at 0, 16, and 26 hours after treatment. Brain water, sodium, potassium, and calcium contents were determined at the 26-hour time point. The level of matrix metalloproteinase-9 in the brain was also determined by Western blot. RESULT: The average number of leukocytes and the concentration of protein in CSF of the QKL adjuvant treatment group were reduced compared with the ampicillin alone group. Brain water, sodium, and calcium contents were reduced in the QKL adjuvant treatment group. The level of MMP-9 in brain tissue was also reduced in the QKL adjuvant treatment group. CONCLUSION: QKL adjuvant treatment alleviates the aggravated inflammatory reaction and partially protects brain tissue from antibiotic-induced injury. The mechanism of this neuroprotective effect of QKL may be due to decreased levels of Ca2+ and MMP-9 in the brain.

Acute Disease↗
PubMed2006

Efficacy of postoperative transarterial chemoembolization and portal vein chemotherapy for patients with hepatocellular carcinoma complicated by portal vein tumor thrombosis--a randomized study.

OBJECTIVES: The aim of this single, randomized study was to explore the efficacy of postoperative transarterial chemoembolization (TACE) and portal vein chemotherapy (PVC) for patients with hepatocellular carcinoma (HCC) complicated by portal vein tumor thrombosis (PVTT) and to evaluate prognostic factors. METHODS: The study cohort consisted of 112 patients with HCC and PVTT randomly divided into three groups: Group A (37 patients), operation only; Group B (35 patients), operation plus TACE; Group C (40 patients), operation plus TACE and PVC. Disease-free survival rates and prognostic factors were analyzed. RESULTS: Most of the side effects and complications were related to the operation, catheters, and local chemotherapy and included liver decompensation (15.0%), catheter obstruction (11.6%), and nausea and loss of appetite (22.1%). The disease-free survival curve was significantly different among the three groups, as estimated by the Kaplan-Meier method (both P < 0.05). Group C showed a significantly higher disease-free survival rate than Group A (P < 0.05), but no statistical differences were found between group A and group B, and group B and group C (both P > 0.05). Tumor size, tumor number, PVTT location, and treatment modalities were independent prognostic factors (P < 0.05). CONCLUSION: Postoperative TACE combined with PVC may benefit the survival of patients with HCC complicated by PVTT in the short-term (less than 60 months), but long-term efficacy is not yet certain and needs to be confirmed by further studies.

Carcinoma, Hepatocellular↗
PubMed2006

Interference of cyclosporine on glucose metabolism: potential role in chronic transplantation kidney fibrosis.

OBJECTIVES: To explore the fibrosis induction effects of cyclosporine (CsA) on renal tubular epithelial cells, as well as the potential mechanisms of CsA-mediated alterations of glucose metabolism in chronic allograft nephropathy (CAN). METHODS: The rat renal tubular epithelial cell line NRK-52E cells were cultured in medium with 50 mmol/L of D-glucose for 7, 14, or 28 days. The expression of TGF-beta1, CTGF, Smad3, and Smad7, which are involved in the fibrosis signal pathway, was detected by immunofluorescence and reverse-transcriptase polymerase chain reaction. Meanwhile, cells were cultured in various concentration of CsA in glucose-free medium for 24 hours followed by the addition of D-[3-(3)H]-glucose for 30 minutes; glucose uptake was detected by examining the radiation intensity. RESULTS: The expression of TGF-beta1, Smad3, Smad7, and CTGF of NRK-52E cells were up-regulated significantly (P < .05) after culture with 50 mmol/L glucose for 7 days compared with those in 25 mmol/L glucose. At 14 and 28 days, TGF-beta1 was slightly decreased compared with 7 days, but CTGF, Smad3, and Smad7 increased robustly (P < .05). CsA significantly stimulated glucose uptake at various concentrations, with an absorption peak at 60 minutes that decreased at 75 minutes. Furthermore, CsA may have dose-dependent effects on glucose uptake. CONCLUSION: High glucose concentrations may play an important role in the NRK-52E cell fibrosis during the CAN process due to an interference of CsA on glucose metabolism.

Animals↗
PubMed2006

Nuclear translocation of SMAD3 may enhance the TGF-beta/SMADS pathway in high glucose circumstances.

OBJECTIVES: Posttransplant diabetes mellitus is one of the most frequent complications after kidney transplantation. It is considered to be one cause of chronic allograft nephropathy. This study sought to investigate the effects of high glucose on the expression and nuclear translocation of Smad3, which is an important signal mediator involved in the fibrotic signal pathway. METHODS: The established rat renal mesangial cell line HBZY-1 was cultured in medium with various concentrations of glucose (4.5 mg/mL, 9.0 mg/mL, or 13.5 mg/mL), which was collected at 7, 14, or 21 days. The total expression of Smad3, including both inner and outer nucleus proteins was examined by Western blot analysis. The nuclear translocated Smad3, representing only the inner nucleus protein, was detected by immunofluorescence staining observed under a laser confocal scanning microscope. RESULTS: No significant difference in the total Smad3 expression was demonstrated by Western blot analysis among the three groups of HBZY-1 cells at various concentration of glucose after 7, 14, or 21 days. There was no fluorescence detected in the nucleus at day 7 by immunofluorescence staining; however, robust positive expression of Smad3 was detected at days 14 and 21. CONCLUSION: As a restricted Smads member, Smad3 protein might not be upregulated in the presence of high glucose. However, with prolonged culture time, Smad3 translocates from cytoplasm to nucleus, which may be a pivotal step in the fibrotic signal pathway.

Animals↗