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Background: The pathogenesis of multiple sclerosis (MS) is mediated primarily by T cells, but most studies of MS and its animal model, experimental autoimmune encephalomyelitis (EAE), have focused on CD4 T cells. The aims of the current study were to determine the pathological interrelationship between CD4 and CD8 autoreactive T cells in MS/EAE., Methods: Female C57BL/6 mice (n = 20) were induced by myelin oligodendrocyte glycoprotein (MOG)35-55 peptide. At 14 days after immunization, T cells were isolated from the spleen and purified as CD4 and CD8 T cells by using CD4 and CD8 isolation kits, and then the purity was determined by flow cytometric analysis. These cells were stimulated by MOG35-55 peptide and applied to proliferation assays. The interferon-gamma (IFN-γ) and interleukin (IL)-4 secretion of supernatant of cultured CD4 and CD8 T cells were measured by enzyme-linked immunosorbent assays (ELISA). For adoptive transfer, recipient mice were injected with MOG35-55-specific CD8 or CD4 T cells. EAE clinical course was measured by EAE score at 0-5 scale and spinal cord was examined by staining with hematoxylin and eosin and Luxol fast blue staining., Results: CD8CD3 and CD4CD3 cells were 86% and 94% pure of total CD3 cells after CD8/CD4 bead enrichment, respectively. These cells were stimulated by MOG35-55 peptide and applied to proliferation assays. Although the CD8 T cells had a generally lower response to MOG35-55 than CD4 T cells, the response of CD8 T cells was not always dependent on CD4. CD8 T cell secreted less IFN-γ and IL-4 compared with CD4 T cells. EAE was induced in wildtype B6 naïve mice by adoptive transfer of MOG35-55-specific T cells from B6 active-induced EAE (aEAE) mice. A similar EAE score and slight inflammation and demyelination were found in naive B6 mice after transferring of CD8 T cells from immunized B6 mice compared with transfer of CD4 T cells., Conclusion: Our data suggest that CD8 autoreactive T cells in EAE have a lower encephalitogenic function but are unique and independent on pathogenic of EAE rather than their CD4 counterparts.

Background: Hypertrophic scar is one of the most common complications and often causes the disfigurement or deformity in burn or trauma patients. Therapeutic methods on hypertrophic scar treatment have limitations due to the poor understanding of mechanisms of hypertrophic scar formation. To throw light on the molecular mechanism of hypertrophic scar formation will definitely improve the outcome of the treatment. This study aimed to illustrate the negative role of eukaryotic initiation factor 6 (eIF6) in the process of human hypertrophic scar formation, and provide a possible indicator of hypertrophic scar treatment and a potential target molecule for hypertrophic scar., Methods: In the present study, we investigated the protein expression of eIF6 in the human hypertrophic scar of different periods by immunohistochemistry and Western blot analysis., Results: In the hypertrophic scar tissue, eIF6 expression was significantly decreased and absent in the basal layer of epidermis in the early period, and increased slowly and began to appear in the basal layer of epidermis by the scar formation time., Conclusions: This study confirmed that eIF6 expression was significantly related to the development of hypertrophic scar, and the eIF6 may be a target molecule for hypertrophic scar control or could be an indicator of the outcomes for other treatment modalities.

Background: While the incidence of paroxysmal nocturnal hemoglobinuria (PNH) is relatively high in Northern China, the exact mechanism of the disease remains unknown. Immunoregulatory cytokine polymorphisms can directly regulate the expression levels of cytokines, which play a crucial role in many diseases. The purpose of this study was to study cytokine gene single nucleotide polymorphisms (SNPs) and the correlated cytokine expression levels in relationship to the PNH pathogenesis., Methods: Peripheral blood samples were collected from 30 PNH patients and 40 healthy donors; all of the samples were collected from the Han people of Northern China. Eight SNP loci in five cytokine genes, including tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), transforming growth factor-beta (TGF-β), interleukin-6 (IL-6), and IL-10, and aplastic anemia (AA) were assessed. TNF-a, TGF-b, IFN-g, IL-6, and IL-10 were analyzed by sequence-specific primer polymerase chain reaction (PCR-SSP). The plasma protein levels of TNF-a, TGF-b, and IFN-g were assessed by an ELISA., Results: The PNH patients had a lower frequency of the TC/GG genotype of the TGF-b gene (P < 0.01) and a higher frequency of the C allele in the TGF-b gene (+10) compared to the controls (P < 0.05). The predominant genotype of the +874 locus of the IFN-g gene was TA in the PNH patients, while that in the predominant genotype was AA in the control group and was statistically significant (P < 0.001). The frequency of the T allele in the IFN-g gene was dramatically higher in the PNH patients than in the controls (P < 0.05). The PNH patients had a reduced frequency of the GC and CC genotypes, as well as the C allele at locus -174 of the IL-6 gene compared to the controls (P < 0.01). In addition, the plasma concentrations of TNF-a, TGF-b, and IFN-g were significantly higher in the PNH group compared to the control group (P < 0.01)., Conclusions: Expression levels of the TNF-a, TGF-b, and IFN-g cytokines play an important role in PNH. The GC and CC genotypes, as well as the C allele of the IL-6 gene may protect the Han people of Northern China against PNH. Additionally, the TC/GG genotype of the TGF-b gene may be the protective allele. In contrast, the TA genotype and the T allele for the IFN-g gene, as well as the C allele of TGF-b may be susceptible to PNH. However, SNPs in the TNF-a and IL-10 genes did not correlate with PNH development. Alternatively, the increased plasma concentrations of TNF-a, TGF-b, and IFN-g in PNH patients may also be related to PNH development.

Background: The mortality and disability associated with progressing ischemic stroke are much higher than general ischemic stroke. This study was conducted to determine the risk factors for progressing ischemic stroke in the Han population of northeast China., Methods: A total of 2511 patients with ischemic stroke within 24 hours admitted to Department of Neurology, First Affiliated Hospital of Harbin Medical University were studied, from November 2007 to May 2009. All of the patients were classified into the progressing or non-progressing group according to the scores of the Scandinavian Neurological Stroke Scale. Fifteen putative risk factors were evaluated. The influence of risk factors for progressing ischemic stroke was analyzed with the simple Logistic analysis, the multiple Logistic analysis, and the stepwise Logistic regression model. All the statistical analysis was performed by SAS 9.1., Results: Totally 359 (14.3%) patients met the criteria for progressing ischemic stroke. The Logistic analysis showed that age, family stroke history, smoking history, hypertension on admission, a drop in blood pressure after admission to the hospital, high serum glucose on admission, and fever were related to progressing ischemic stroke in the Han population of northeast China., Conclusion: People of the ischemic stroke with these factors are more likely to develop progressing ischemic stroke.

Background: An increasing incidence of disease caused by nontuberculous mycobacteria (NTM) is being reported. The purpose of this study was to determine the isolation rates of NTM from various clinical specimens, and their antimicrobial susceptibility patterns, over a 4-year period in Shanghai., Methods: All NTM isolated between 2005 and 2008 at Shanghai Pulmonary Hospital, a key laboratory of mycobacteria tuberculosis in Shanghai, China, were identified with conventional biochemical tests and 16S rRNA gene sequencing. Antimicrobial susceptibility for all NTM was determined using the BACTEC MGIT 960 system., Results: A total of 21,221 specimens were cultured, of which 4868 (22.94%) grew acid fast bacilli (AFB), and 248 (5.09%) of the AFB were NTM. The prevalence rate of NTM was determined as 4.26%, 4.70%, 4.96% and 6.38% among mycobacteria culture positive samples in years 2005, 2006, 2007 and 2008 respectively. These data indicated that the prevalence rate has continuously increased. Sixteen different species of NTM were identified, the most commonly encountered NTM in Shanghai were M. chelonae (26.7%), followed by M. fortuitum (15.4%), M. kansasii (14.2%), M. avium-intracellulare complex (13.1%) and M. terrae (6.9%). The rare species identified were M. marinum, M. gastri, M. triviale, M. ulcerans, M. smegmatis, M. phlci, M. gordonae, M. szulgai, M. simiae, M. scrofulaceum and M. xenopi. The five most commonly identified NTM species showed high drug resistance to general anti-tuberculosis drugs, particularly, M. chelonae and M. fortuitum appear to be multi-drug resistance., Conclusions: The prevalence of NTM in Shanghai showed a tendency to increase over the course of the study. The five most commonly isolated NTM species showed high drug resistance to first line anti-tuberculosis drugs.

Background: No-reflow phenomenon during percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) is a predictive factor of continuous myocardial ischemia, ventricular remodeling and cardiac dysfunction, which is closely associated with a worse prognosis. This study aimed to evaluate intracoronary nitroprusside in the prevention of the no-reflow phenomenon in AMI., Methods: Ninety-two consecutive patients with AMI, who underwent primary PCI within 12 hours of onset, were randomly assigned to 2 groups: intracoronary administration of nitroprusside (group A, n = 46), intracoronary administration of nitroglycerin (group B, n = 46). The angiographic results were observed. The real-time myocardial contrast echocardiography (RT-MCE), including contrast score index (CSI), wall motion score index (WMSI), transmural contrast defect length (CDL) and serious WM abnormal length (WML) were recorded at 24 hours and 1 week post-PCI. High sensitivity C-reactive protein (Hs-CRP) was examined by immune rate nephelometry. N-terminal prohormone brain natriuretic peptide (NT-proBNP) was tested with enzyme-linked immunosorbent assay. Patients were followed up for six months. Major adverse cardiac events (MACE) were recorded., Results: The incidence of final TIMI-3 flow in group A was much higher than that in Group B (P < 0.05), final corrected TIMI frame count (cTFC) in group A decreased significantly than that in group B (P < 0.01). The CSI, CDL/LV length, WMSI and WL/LV length in group A were significantly lower than that in group B (P < 0.01). Levels of Hs-CRP and NT-proBNP at 1 week post-PCI decreased significantly in group A than that in group B (P < 0.01). Patients were followed up for 6 months and the incidence of MACE in group A was significantly lower than that in group B (P < 0.05)., Conclusion: Intracoronary nitroprusside can improve myocardial microcirculation, leading to the decrease of the incidence of no-reflow phenomenon and better prognosis.

Background: We hypothesize that increased atrial oxidative stress and inflammation may play an important role in atrial nerve sprouting and heterogeneous sympathetic hyperinnervation during atrial fibrillation (AF). To test the hypothesis, we examined whether the antioxidant and anti-inflammatory treatment with probucol attenuates atrial autonomic remodeling in a canine model of AF produced by prolonged rapid right atrial pacing., Methods: Twenty-one dogs were divided into a sham-operated group, a control group and a probucol group. Dogs in the control group and probucol group underwent right atrial pacing at 400 beats per minute for 6 weeks, and those in the probucol group received probucol 1 week before rapid atrial pacing until pacing stopped. After 6-week rapid atrial pacing, general properties including left atrial structure and function, atrial hemodynamics and the inducibility and duration of AF were measured in all the groups. Atrial oxidative stress markers and serum C-reactive protein (CRP) concentration were estimated. The degree of nerve sprouting and sympathetic innervation at the right atrial anterior wall (RAAW) and the left atrial anterior wall (LAAW) were quantified by immunohistochemistry, atrial norepinephrine contents were also detected. Atrial beta-nerve growth factor (beta-NGF) mRNA and protein expression at the RAAW and LAAW were assessed by real-time quantitative RT-PCR and Western blotting respectively., Results: Atrial tachypacing induced significant nerve sprouting and heterogeneous sympathetic hyperinnervation, and the magnitude of nerve sprouting and hyperinnervation was higher in the RAAW than in the LAAW. Atrial beta-NGF mRNA and protein levels were significantly increased at the RAAW and LAAW, and the upregulation of beta-NGF expression was greater at the RAAW than at the LAAW in the control group. The beta-NGF protein level was positively correlated with the density of sympathetic nerves in all groups. Probucol decreased the increase of CRP concentration and attenuated atrial oxidative stress caused by atrial tachypacing. In addition, probucol could effectively inhibit atrial beta-NGF upregulation, significantly attenuate atrial nerve sprouting and heterogeneous sympathetic hyperinnervation, and dramatically reduce the inducibility and duration of AF., Conclusions: The atrial over-expression of beta-NGF possibly caused by increased oxidative stress and inflammation may be the main mechanism underlying atrial autonomic remodeling during AF. Probucol attenuates atrial autonomic remodeling possibly by its antioxidant and anti-inflammatory actions.

Background: Renin-angiotensin-aldosterone system has been demonstrated to be associated with both congestive heart failure (CHF) and atrial fibrillation (AF). This study investigated the effects of spironolactone, a kind of aldosterone antagonist, on atrial electrical remodeling and fibrosis in CHF dogs induced by chronic rapid ventricular pacing., Methods: Twenty one dogs were randomly divided into sham-operated group, control group, and spironolactone group. In control group and spironolactone group, dogs were ventricular paced at 220 beats per minute for 6 weeks. Additionally, spironolactone at 15 mg x kg(-1) x d(-1) was given to dogs 1 week before rapid ventricular pacing until pacing stopped. Transthoracic and transoesophageal echocardiographic examinations were performed to detect structural and functional changes of the atrium. Swan2 Ganz floating catheters were used to measure hemadynamics variances. Atrial effective refractory period (AERP), AERP dispersion (AERPd), intra- and inter-atrium conduction time (CT) and intra-atrium conduction velocity (CV) were determined. The inducibility and duration of AF were also measured in all groups. Finally, atrial fibrosis was quantified with Masson staining., Results: AERP did not change significantly after dogs were ventricular paced for 6 weeks. However, AERPd, intra- and inter-atrium CT increased significantly, and CV decreased apparently, which was negatively correlated to the atrial fibrosis (r = -0.74, P < 0.05). Simultaneously, left atriums were enlarged and cardiac hemadynamics worsened in pacing dogs. Although spironolactone could not affect cardiac hemadynamics effectively, it can obviously improve left atrial ejection fraction (P < 0.05). Spironolactone treatment did not alter AERP duration, but this medicine dramatically decreased AERPd (P < 0.05), shortened intra- and inter-atrium conduction time (P < 0.05), and increased atrium CV. Moreover, spironolactone decreased the inducibility and duration of AF (P < 0.05), as well as atrial fibrosis (P < 0.01) induced by chronic rapid ventricular pacing., Conclusion: Spironolactone contributes to AF prevention in congestive heart failure dogs induced by chronic rapid ventricular pacing, which is related to atrial fibrosis reduction and independent of hemadynamics.

Background: Experimental autoimmune myocarditis (EAM) in rats is a T-cell-mediated disorder. The initiation and maintenance of autoimmune responses in EAM depend on the maturation state of dendritic cells. IL-10 is a pleiotrophic immunomodulatory cytokine that functions at different levels of the immune response, so it has emerged as a promising therapeutic factor for the treatment of autoimmune/inflammatory diseases. This study was designed to test the hypothesis that IL-10 gene modified bone marrow-derived immature dendritic cells (iDCs) ameliorate EAM and to explore the underlying mechanisms., Methods: EAM was induced using the methods of cardiac myosin immunization on day 0 and day 7. Immature and mature bone marrow-derived dendritic cells (BMDCs) were generated without or with the stimulation by lipopolysaccharide (LPS) and the phenotype was analyzed by flow cytometry. Some of the iDCs were transfected by pcDNA3-IL-10 plasmid. 2 x 10(6)/per rat mature DC (mDC), immature DC (iDC), pcDNA3 transfected iDC, pcDNA3-IL-10 transfected iDC or phosphate buffered saline (PBS) were injected intravenously for treatment 5 days after the first immunization. On day 21, HE staining was performed to detect the myocardial inflammation and T lymphocyte proliferation assay was used to determine the effects of IL-10 gene transfected iDC on autoreactive T cell proliferation. Expression of IkappaB, the inhibitor of NF-kappaB pathway, was determined by Western blot., Results: BMDCs generated in a medium supplemented with granulocyte-macrophage-colony-stimulating factor (GM-CSF) were relatively immature, as determined by flow cytometry. However, stimulation with LPS induced these cells to become mature (m) DCs with higher levels of surface major histocompatibility complex (MHC)-II and costimulatory molecules. Intravenous administration of iDCs, especially pcDNA3-IL-10 transfected iDC, ameliorated the histopathological severity of the myosin induced-EAM, and the effect was lost after the DCs underwent maturation induced by in vitro exposure to LPS. IL-10 gene modified iDC inhibited the antigen specific T cell responses towards cardiac myosin. IkappaB protein was up-regulated significantly in the IL-10 gene modified iDC group., Conclusions: IL-10 gene modified iDC induced antigen-specific tolerance in EAM. The underlying mechanisms may be related to costimulatory molecules down-regulation and NF-kappaB pathway inhibition.

Background: Atrial electrical remodeling (AER) contributes to the maintainance of atrial fibrillation (AF). This study was to compare the effects of Losartan with those of Diltiazem on tachycardia-induced acute AER in rabbits., Methods: Twenty-one rabbits paced with maximal atrial capture rate for 3 hours in the right atrium (RA) were randomly divided into saline group, Diltiazem group and Losartan group. After autonomic blockage, we measured atrial effective refractory period (AERP), AERP rate adapting feature, AERP dispersion and RA conduction time at basic cycle lengths (BCLs) of 200 ms and 150 ms at baseline, 0.5 hour, 1 hour, 2 and 3 hours after rapid atrial pacing., Results: In the saline group, there was a prompt decrease in AERP as a result of rapid atrial pacing, and AERP200 and AERP150 were shortened sharply within 0.5 hour of pacing (30.2 +/- 10.5 ms and 24.1 +/- 9.1 ms, respectively). The AERP did not change dramatically in the Diltiazem and Losartan groups. In the saline group, the value of (AERP200-AERP150)/50 ms in high RA was 0.17 +/- 0.08 at baseline and became significantly smaller at 0.5 hour (0.08 +/- 0.06), 1 hour (0.09 +/- 0.06), 2 hours (0.08 +/- 0.04) and 3 hours (0.09 +/- 0.05) (all P < 0.05), suggesting a reduction of rate adaptation of AERP. The value of (AERP200-AERP150)/50 ms in high RA did not change during the 3 hours of pacing in both Diltiazem and Losartan groups. In the saline group, AERP dispersion increased significantly at 2 and 3 hours (P < 0.05). However, Diltiazem could not prevent the increase of AERP dispersion at 3 hours (P < 0.05). During Losartan infusion, the AERP dispersion was no longer increased after rapid atrial pacing. There was no significant difference in RA conduction time among the three groups., Conclusion: Like calcium antagonist Diltiazem, Losartan could prevent AERP shortening and preserve rate adaptation of AERP after rapid atrial pacing. Losartan is more effective than Diltiazem in inhibiting the increase of AERP dispersion.