[Hesperetin attenuates angiotensin II-induced collagen expression in cardiac fibroblasts in vitro]

OBJECTIVE

To explore the effect of hesperetin (HES) on collagen expression in cardiac fibroblasts in vitro induced by angiotensin II (AngII).

METHODS

Cell growth was determined by trypan blue staining, reactive oxygen species (ROS) generation by microplate reader, the expressions of collagen I,III and matrix metalloproteinase 1 (MMP-1) by real-time polymerase chain reaction (PCR) and cell proliferation by cell counting kit-8.

RESULTS

HES and AngII+HES had no effect on cellular activity. AngII significantly increased ROS generation (1.70 ± 0.12 vs 1, P < 0.01), gene expression of collagen I,III both increased (1.31 ± 0.08 vs 1, 1.40 ± 0.09 vs 1, both P < 0.01) while MMP-1 decreased (0.68 ± 0.03 vs 1, P < 0.01). Ang II also induced the proliferation of fibroblasts (1.91 ± 0.18 vs 1, P < 0.01). While HES (25, 50, 100 µmol/L) or NAC (1 mmol/L) reversed these effects during co-treating with AngII, ROS decreased versus the Ang II group(1.37 ± 0.05, 1.16 ± 0.08, 1.07 ± 0.07, 1.12 ± 0.07 vs 1.70 ± 0.12, all P < 0.01) , gene expression of collagenI,III also decreased (1.22 ± 0.08 and 1.27 ± 0.07, 1.14 ± 0.07 and 1.00 ± 0.06, 1.02 ± 0.06 and 0.99 ± 0.05, 1.08 ± 0.07 and 1.09 ± 0.06 vs 1.31 ± 0.08 and 1.40 ± 0.09, all P < 0.01), MMP-1 increased (0.76 ± 0.05, 0.88 ± 0.07, 1.01 ± 0.08, 0.96 ± 0.07 vs 0.68 ± 0.03, P < 0.01) versus the Ang II group. Cell proliferation was also inhibited (1.42 ± 0.07, 1.38 ± 0.03, 1.07 ± 0.15, 1.16 ± 0.11 vs 1.91 ± 0.18, all P < 0.01). NAC had the same effect with HES.

CONCLUSION

HES inhibits the synthesis of collagen and the Ang II-induced proliferation of fibroblast through suppressing the ROS generation.

Disruption of tumor necrosis factor receptor associated factor 5 exacerbates pressure overload cardiac hypertrophy and fibrosis

The cytoplasmic signaling protein tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5), which was identified as a signal transducer for members of the TNF receptor super-family, has been implicated in several biological functions in T/B lymphocytes and the innate immune response against viral infection. However, the role of TRAF5 in cardiac hypertrophy has not been reported. In the present study, we investigated the effect of TRAF5 on the development of pathological cardiac hypertrophy induced by transthoracic aorta constriction (TAC) and further explored the underlying molecular mechanisms. Cardiac hypertrophy and function were evaluated with echocardiography, hemodynamic measurements, pathological and molecular analyses. For the first time, we found that TRAF5 deficiency substantially aggravated cardiac hypertrophy, cardiac dysfunction and fibrosis in response to pressure overload after 4 weeks of TAC compared to wild-type (WT) mice. Moreover, the mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK)-extracellular signal-regulated kinases 1/2 (ERK1/2) signaling pathway was more activated in TRAF5-deficient mice than WT mice. In conclusion, our results suggest that as an intrinsic cardioprotective factor, TRAF5 plays a crucial role in the development of cardiac hypertrophy through the negative regulation of the MEK-ERK1/2 pathway. J. Cell. Biochem. 115: 349-358, 2014. © 2013 Wiley Periodicals, Inc.

Analysis of age of onset, pre-existing infections, and features of magnetic resonance imaging results in patients with acute myelitis

The clinical features and potential risk factors of acute myelitis (AM) were investigated. The medical records of patients with AM admitted to our department between January 2004 and December 2011 were collected and retrospectively analyzed. The diagnosis of AM was in line with the diagnostic criteria of the Transverse Myelitus Consortium Working Group. The age of onset, clinical, and imaging features of these patients were analyzed. A total of 64 patients satisfying the inclusion criteria were enrolled in the study, including 39 males and 25 females. The patients ranged in age from 1 to 80 years, with a mean age of 34 years. Twenty-three patients had symptoms of pre-existing infections. The correlation between spinal cord lesions and spinal lesions was statistically significant (P<0.05). Cervical spinal cord inflammation was the most common. Prodromal infections were more commonly observed in thoracic spinal cord myelitis than in cervical spinal cord myelitis (P<0.05). AM appears to be more likely to occur in male minors. Lesions of the spinal column were partially implicated with the occurrence of myelitis, which suggests that such lesions might be a predisposing factor. Compared to AM of the cervical cord, pre-existing infections appear to be of greater significance for the occurrence of myelitis of the thoracic cord.

Never in mitosis gene A related kinase-6 attenuates pressure overload-induced activation of the protein kinase B pathway and cardiac hypertrophy

Cardiac hypertrophy appears to be a specialized form of cellular growth that involves the proliferation control and cell cycle regulation. NIMA (never in mitosis, gene A)-related kinase-6 (Nek6) is a cell cycle regulatory gene that could induce centriole duplication, and control cell proliferation and survival. However, the exact effect of Nek6 on cardiac hypertrophy has not yet been reported. In the present study, the loss- and gain-of-function experiments were performed in Nek6 gene-deficient (Nek6^−/−) mice and Nek6 overexpressing H9c2 cells to clarify whether Nek6 which promotes the cell cycle also mediates cardiac hypertrophy. Cardiac hypertrophy was induced by transthoracic aorta constriction (TAC) and then evaluated by echocardiography, pathological and molecular analyses in vivo. We got novel findings that the absence of Nek6 promoted cardiac hypertrophy, fibrosis and cardiac dysfunction, which were accompanied by a significant activation of the protein kinase B (Akt) signaling in an experimental model of TAC. Consistent with this, the overexpression of Nek6 prevented hypertrophy in H9c2 cells induced by angiotonin II and inhibited Akt signaling in vitro. In conclusion, our results demonstrate that the cell cycle regulatory gene Nek6 is also a critical signaling molecule that helps prevent cardiac hypertrophy and inhibits the Akt signaling pathway.

Hesperetin attenuates mitochondria-dependent apoptosis in lipopolysaccharide-induced H9C2 cardiomyocytes

Apoptosis is closely associated with the occurrence and development of cardiovascular diseases and is considered as one of the crucial pathological processes of cardiomyopathy, sepsis, ischemia/reperfusion injury, myocardial infarction and heart failure. Hesperetin (HES), a flavanone glycoside found in citrus fruit peels, has been known to exhibit several key biological and pharmacological properties. Previous studies have demonstrated the anti-inflammatory, anti-oxidant and anti-tumor functions of HES. However, with regards to the pro- or anti-apoptotic functions of HES, there are several disagreements within the literature. To examine whether HES has protective effects in cardiac apoptosis, the present study examined the role of HES in lipopolysaccharide (LPS)-stimulated H9C2 cardiomyocytes, aiming to clarify the possible mechanisms underlying its effects. In the present study, HES reduced the percentage of viable apoptotic (VA) cells in a flow cytometry analysis. It had an anti-apoptosis function in LPS-stimulated H9C2 cells. To clarify whether HES alleviated LPS-stimulated apoptosis through the mitochondria-dependent intrinsic apoptotic pathway, certain indicators of this pathway were detected, including members of the caspase family. The data revealed that HES attenuated the activation of capase-3 and caspase-9. These results indicated HES has a mitochondria-dependent anti-apoptosis effect in LPS-stimulated H9C2 cells. To explore the possible mechanisms, the protein expression levels of certain markers in the possible signaling pathway were detected, including JNK and Bcl-2 family. As a result, HES downregulated the protein expression of Bax, upregulated the expression of Bcl-2 and attenuated the phosphorylation level of JNK. Therefore, the anti-apoptosis effects of HES were possibly mediated by the JNK/Bax signaling pathway. In conclusion, HES has a mitochondria-dependent anti-apoptosis effect in LPS-induced H9C2 cells via the JNK/Bax signaling pathway.

Evaluation of bamboo genetic diversity using morphological and SRAP analyses

Bamboo is an important member of the giant grass subfamily Bambusoideae of Poaceae. In this study, 13 bamboo accessions belonging to 5 different genera were subjected to morphological evaluation and sequence-related amplified polymorphism (SRAP) analysis. Unweighted pair-group method of arithmetic averages (UPGMA) cluster analysis was used to construct a dendrogram and to estimate the genetic distances among accessions. On the basis of morphological characteristics, the 13 accessions were distinctly classified into 2 major clusters; 3 varieties, PPYX, PGNK, and PLYY were grouped as cluster A, and 10 accessions were categorized under cluster B. Similarity coefficients ranging from 0.23 to 0.96 indicated abundant genetic variation among bamboo varieties. Approximately 38 SRAP primer combinations generated 186 bands, with 150 bands (80.65%) showing polymorphisms among the 13 accessions. Based on SRAP analysis, 13 bamboo accessions were grouped into 3 major clusters. Five species comprised Cluster I (PASL, PLYY, PTSC, SCNK, and BMAK), which belongs to genus Phyllostachys. Cluster II consisted of 5 varieties, PASL, PLYY, PTSC, SCNK, and BMAK; Cluster III included 3 varieties, PGNK, PLSY, and BMRS. Comparison of the results generated by morphological and SRAP analyses showed that the classification based on SRAP markers was more concordant to the taxonomic results of Gamble than that performed using morphological characters, thus suggesting that SRAP analysis is more efficient in evaluating genetic diversity in bamboos compared to morphological analysis. The SRAP technique serves as an alternative method in assessing genetic diversity within bamboo collections.

Metformin promotes autophagy and apoptosis in esophageal squamous cell carcinoma by downregulating Stat3 signaling

The antidiabetic drug metformin exerts chemopreventive and antineoplastic effects in many types of malignancies. However, the mechanisms responsible for metformin actions appear diverse and may differ in different types of cancer. Understanding the molecular and cellular mechanisms specific for different cancers is important to optimize strategy for metformin treatment in different cancer types. Here, we investigate the in vitro and in vivo effects of metformin on esophageal squamous cell carcinoma (ESCC) cells. Metformin selectively inhibited cell growth in ESCC tumor cells but not immortalized noncancerous esophageal epithelial cells. In addition to apoptosis, metformin triggered autophagy. Pharmacological or genetic inhibition of autophagy sensitized ESCC cells to metformin-induced apoptotic cell death. Mechanistically, signal transducer and activator of transcription 3 (Stat3) and its downstream target Bcl-2 was inactivated by metformin treatment. Accordingly, small interfering RNA (siRNA)-mediated Stat3 knockdown enhanced metformin-induced autophagy and apoptosis, and concomitantly enhanced the inhibitory effect of metformin on cell viability. Similarly, the Bcl-2 proto-oncogene, an inhibitor of both apoptosis and autophagy, was repressed by metformin. Ectopic expression of Bcl-2 protected cells from metformin-mediated autophagy and apoptosis. In vivo, metformin downregulated Stat3 activity and Bcl-2 expression, induced apoptosis and autophagy, and inhibited tumor growth. Together, inactivation of Stat3-Bcl-2 pathway contributes to metformin-induced growth inhibition of ESCC by facilitating crosstalk between apoptosis and autophagy.

Effect of the IkBα mutant gene delivery to mesenchymal stem cells on rat chronic pancreatitis

This study aimed to investigate the effect of inhibitors of the NF-kΒ alpha mutant gene (IkBaM) delivery to mensenchymal stem cells (MSCs) on rat chronic pancreatitis (CP). A total of 120 Sprague-Dawley rats were randomly divided into 6 groups of 20: Group A was injected with sterile saline solution, Group B was injected with allogenic MSCs, Group C1 was injected with allogenic IkBαM-MSCs cultured in vitro 4 h before CP modeling, Group C2 was injected with allogenic IkBαM-MSCs cultured in vitro during CP modeling, Group C3 was cultured with allogenic IkBαM-MSCs cultured in vitro 4 h after CP modeling, and Group D was injected with rAAV2-MSCs. Cytokine levels of ICAM-1, CTGF, IL-1, IL-6, IL-8, TNF-α, TIMP-1, TIMP-2, IL-10, FN, MMP-1, MMP-2, MMP-3, and MMP-9 were examined. The results indicated that allogenic IκBαM-MSCs could reduce pro-inflammatory cytokine levels and increase anti-inflammatory cytokine levels in CP. The allogenic IkBαM-MSCs reduced the activation and promoted the apoptosis of pancreatic stellate cells in the rat model of CP. IkBαM-MSCs influenced the proliferation and apoptosis of pancreatic stellate cells by regulating the activation of the PPAR, MAPK, mTOR, TGF-β, NOD-like receptor, Notch, WNT, TGF-β1-SMAD-2/3, and P53 signal transduction pathways.

Attenuation of donor-reactive T cells allows effective control of allograft rejection using regulatory T cell therapy

Regulatory T cells (Tregs) are essential for the establishment and maintenance of immune tolerance, suggesting a potential therapeutic role for Tregs in transplantation. However, Treg administration alone is insufficient in inducing long-term allograft survival in normal hosts, likely due to the high frequency of alloreactive T cells. We hypothesized that a targeted reduction of alloreactive T effector cells would allow a therapeutic window for Treg efficacy. Here we show that preconditioning recipient mice with donor-specific transfusion followed by cyclophosphamide treatment deleted 70-80% donor-reactive T cells, but failed to prolong islet allograft survival. However, infusion of either 5 × 10(6) Tregs with direct donor reactivity or 25 × 10(6) polyclonal Tregs led to indefinite survival of BALB/c islets in more than 70% of preconditioned C57BL/6 recipients. Notably, protection of C3H islets in autoimmune nonobese diabetic mice required islet autoantigen-specific Tregs together with polyclonal Tregs. Treg therapy led to significant reduction of CD8(+) T cells and concomitant increase in endogenous Tregs among graft-infiltrating cells early after transplantation. Together, these results demonstrate that reduction of the donor-reactive T cells will be an important component of Treg-based therapies in transplantation.

Pretreatment of furfural industrial wastewater by Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate processes: a comparative study

The Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate (PDS) processes have been applied for the treatment of actual furfural industrial wastewater in this paper. Through the comparative study of the three processes, a suitable pretreatment technology for actual furfural wastewater treatment was obtained, and the mechanism and dynamics process of this technology is discussed. The experimental results show that Fenton technology has a good and stable effect without adjusting pH of furfural wastewater. At optimal conditions, which were 40 mmol/L H₂O₂ initial concentration and 10 mmol/L Fe²⁺ initial concentration, the chemical oxygen demand (COD) removal rate can reach 81.2% after 90 min reaction at 80 °C temperature. The PDS process also has a good performance. The COD removal rate could attain 80.3% when Na₂S₂O₈ initial concentration was 4.2 mmol/L, Fe²⁺ initial concentration was 0.1 mol/L, the temperature remained at 70 °C, and pH value remained at 2.0. The electro-Fenton process was not competent to deal with the high-temperature furfural industrial wastewater and only 10.2% COD was degraded at 80 °C temperature in the optimal conditions (2.25 mA/cm² current density, 4 mg/L Na₂SO₄, 0.3 m³/h aeration rate). For the Fenton, electro-Fenton and PDS processes in pretreatment of furfural wastewater, their kinetic processes follow the pseudo first order kinetics law. The pretreatment pathways of furfural wastewater degradation are also investigated in this study. The results show that furfural and furan formic acid in furfural wastewater were preferentially degraded by Fenton technology. Furfural can be degraded into low-toxicity or nontoxic compounds by Fenton pretreatment technology, which could make furfural wastewater harmless and even reusable.

Clinical grade manufacturing of human alloantigen-reactive regulatory T cells for use in transplantation

Regulatory T cell (Treg) therapy has the potential to induce transplantation tolerance so that immunosuppression and associated morbidity can be minimized. Alloantigen-reactive Tregs (arTregs) are more effective at preventing graft rejection than polyclonally expanded Tregs (PolyTregs) in murine models. We have developed a manufacturing process to expand human arTregs in short-term cultures using good manufacturing practice-compliant reagents. This process uses CD40L-activated allogeneic B cells to selectively expand arTregs followed by polyclonal restimulation to increase yield. Tregs expanded 100- to 1600-fold were highly alloantigen reactive and expressed the phenotype of stable Tregs. The alloantigen-expanded Tregs had a diverse TCR repertoire. They were more potent than PolyTregs in vitro and more effective at controlling allograft injuries in vivo in a humanized mouse model.

The nature and origin of nucleus-like intracellular inclusions in Paleoproterozoic eukaryote microfossils

The well-known debate on the nature and origin of intracellular inclusions (ICIs) in silicified microfossils from the early Neoproterozoic Bitter Springs Formation has recently been revived by reports of possible fossilized nuclei in phosphatized animal embryo-like fossils from the Ediacaran Doushantuo Formation of South China. The revisitation of this discussion prompted a critical and comprehensive investigation of ICIs in some of the oldest indisputable eukaryote microfossils-the ornamented acritarchs Dictyosphaera delicata and Shuiyousphaeridium macroreticulatum from the Paleoproterozoic Ruyang Group of North China-using a suite of characterization approaches: scanning electron microscopy (SEM), transmission electron microscopy (TEM), and focused ion beam scanning electron microscopy (FIB-SEM). Although the Ruyang acritarchs must have had nuclei when alive, our data suggest that their ICIs represent neither fossilized nuclei nor taphonomically condensed cytoplasm. We instead propose that these ICIs likely represent biologically contracted and consolidated eukaryotic protoplasts (the combination of the nucleus, surrounding cytoplasm, and plasma membrane). As opposed to degradational contraction of prokaryotic cells within a mucoidal sheath-a model proposed to explain the Bitter Springs ICIs-our model implies that protoplast condensation in the Ruyang acritarchs was an in vivo biologically programmed response to adverse conditions in preparation for encystment. While the discovery of bona fide nuclei in Paleoproterozoic acritarchs would be a substantial landmark in our understanding of eukaryote evolution, the various processes (such as degradational and biological condensation of protoplasts) capable of producing nuclei-mimicking structures require that interpretation of ICIs as fossilized nuclei be based on comprehensive investigations.

Large adipocytes function as antigen-presenting cells to activate CD4(+) T cells via upregulating MHCII in obesity

BACKGROUND/OBJECTIVES

Although obesity is associated with low-grade inflammation and metabolic disorders, clinical studies suggested some obese people were metabolically healthy with smaller adipocyte size compared with metabolically abnormal obese (MAO). This indicated adipocyte size may be an important predictor underlay the distinction between MAO and metabolically healthy obese. As recent study has shown that adipocytes expressed class II major histocompatibility complex (MHCII), which functioned as APCs during obesity. However, the relationship between adipocyte hypertrophy and MHCII expression was not involved. Here we hypothesize that hypertrophic adipocytes could be associated with upregulating MHCII to influence adipose tissue metabolism.

METHODS

Adipocytes were sorted by fluorescence-activated cell sorting (FACS) according to the cell size from MAO mice. The activation of MHCII, T cells and related signaling molecules were examined by FACS, ELISA and western blotting. 3T3-L1 cell line and primary adipocytes were used to examine the effect of free fatty acids (FFA) on adipocytes enlargement and MHCII expression.

RESULTS

MAO mice had a significant increase in adipocytes size and FFA concentration. The large adipocytes from both obese and non-obese mice expressed higher levels of MHCII than small adipocytes. Importantly, large adipocytes from obese mice stimulated CD4(+) T cells to secrete more interferon (IFN)-γ. Furthermore, the activation of the JNK-STAT1 pathway was involved in upregulation of MHCII in large adipocytes. In vitro FFA treatment promoted adipocyte hypertrophy and expression of MHCII-associated genes.

CONCLUSIONS

This study demonstrates that large adipocytes highly express MHCII and function as APC to stimulate IFN-γ-expressing CD4(+) T cells, in which FFA may have important roles before IFN-γ elevated. These findings suggest that adipocyte hypertrophy, rather than overall obesity, is the major contributor to adipose tissue inflammation and insulin resistance.

Lentiviral-mediated p38 MAPK RNAi attenuates aldosterone-induced myocyte apoptosis

Aldosterone-induced myocyte apoptosis is an important component of cardiovascular disease. While the p38 mitogen-activated protein kinase (p38 MAPK) pathway has been shown to be crucial in myocyte apoptosis, whether aldosterone induces myocyte apoptosis through this pathway remains unclear. In the present study, three individual strands of p38 MAPK short hairpin RNA (ShRNA), delivered by lentiviral vectors (PGLV), were constructed and used to explore the role of p38 MAPK pathway activation in aldosterone-mediated myocyte apoptosis in cultured myocytes and normotensive rats. Aldosterone stimulation increased myocyte apoptosis, caspase-3 expression levels and p38 MAPK mRNA and protein expression levels in vitro and in vivo. PGLV-ShRNA3 transduction decreased aldosterone-mediated myocyte apoptosis and p38 MAPK mRNA and protein expression levels in vitro (all P<0.01). PGLV-ShRNA3 transduction significantly decreased aldosterone-mediated myocyte apoptosis, p38 MAPK mRNA and protein expression levels in normotensive rats (P<0.01, P<0.01 and P<0.05, respectively). Results from the present study suggest that aldosterone directly induces myocyte apoptosis through the p38 MAPK pathway and the gene silencing of p38 MAPK may protect cardiac myocytes from aldosterone-mediated apoptosis.

Changes in and shortcomings of drug stockpiling, vaccine development and related policies during outbreaks of avian influenza A H5N1, H1N1, and H7N9 among humans

The purpose of this paper is to provide a reference for the future stockpiling of drugs and developing vaccines for treatment of emerging infectious diseases by summarizing the status of drug stockpiling, vaccine development, and related policies during three major outbreaks of avian influenza among humans (H5N1 in 2003, H1N1 in 2009, and H7N9 in 2013). Documents regarding drug stockpiling and vaccine development during three influenza outbreaks have been reviewed. Results indicated that the response to pandemic influenza outbreaks has improved markedly in terms of stockpiles of antivirals and vaccine development. These improvements also suggest advances in related policy planning. These trends also foreshadow better prospects for prevention and control of emerging infectious diseases. However, the rationality of drug stockpiling and international cooperation still needs to be enhanced.

Serum level of soluble fibrinogen-like protein 2 in renal allograft recipients with acute rejection: a preliminary study

BACKGROUND

Soluble fibrinogen-like protein 2 (sfgl2), which is mainly secreted by T cells, is a novel effector of regulatory T cells with immunosuppressive functions. The aim of this study was to investigate serum levels of sfgl2 among renal allograft recipients.

METHODS

From November 2010 to August 2011 we retrospectively divided 47 renal allograft recipients into an acute rejection (n = 19) versus a stable group (n = 28) according to allograft biopsy results, using the Banff 2007 classification. The acute rejection group was subdivided into grade I (n = 8) versus grade II T-cell-mediated (n = 6) or antibody-mediated rejection episodes (n = 5). Peripheral blood samples were collected at the time of biopsy. Fourteen healthy volunteers were included as normal group controls. Serum levels of sfgl2 were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Serum levels of sfgl2 were increased among renal allograft recipients suffering from biopsy-proven acute rejection episodes (61.91 ± 45.68 ng/mL), versus those with stable allografts (38.59 ± 19.92 ng/mL, P < .05) or healthy volunteers (29.10 ± 18.08 ng/mL, P < .05). The sfgl2 level was significantly higher among patients with antibody-mediated (118.48 ± 55.54 ng/mL) than T-cell-mediated acute rejection episodes (41.71 ± 16.44 ng/mL, P < .01). Serum sfgl2 levels were remarkably elevated in patients with grade II (51.87 ± 19.13 ng/mL) versus grade I T-cell-mediated rejection (34.10 ± 9.26 ng/mL, P < .05).

CONCLUSIONS

Serum sfgl2 levels were increased among renal allograft recipients with acute rejection episodes to an extent dependent upon the pathological type and severity of the response.

IL-33 attenuates anoxia/reoxygenation-induced cardiomyocyte apoptosis by inhibition of PKCβ/JNK pathway

BACKGROUND

Interleukin-33 (IL-33) is a new member of the IL-1 cytokine family. The objectives of present study are to assess whether IL-33 can protect cardiomyocytes from anoxia/reoxygenation (A/R)-induced injury and the mechanism involved in the protection.

METHODS

Cardiomyocytes derived from either wild type or JNK1(-/-) mice were challenged with an A/R with or without IL-33. Myocyte apoptosis was assessed by measuring caspase 3 activity, fragmented DNA and TUNEL staining. In addition, cardiomyocyte oxidative stress was assessed by measuring DHR123 oxidation; PKCβII and JNK phosphorylation were assessed with Western blot.

RESULTS

Challenge of cardiomyocytes with an A/R resulted in cardiomyocyte oxidative stress, PKCβII and JNK phosphorylation, and myocyte apoptosis. Treatment of the cardiomyocytes with IL-33 attenuated the A/R-induced myocyte oxidative stress, prevented PKCβII and JNK phosphorylation and attenuated the A/R-induced myocyte apoptosis. The protective effect of the IL-33 did not show in cardiac myocytes with siRNA specific to PKCβII or myocytes deficient in JNK1. Inhibition of PKCβII prevented the A/R-induced JNK phosphorylation, but inhibition of JNK1 showed no effect on A/R-induced PKCβII phosphorylation.

CONCLUSIONS

Our results indicate that IL-33 prevents the A/R-induced myocyte apoptosis through inhibition of PKCβ/JNK pathway.

High-resolution capillary isoelectric focusing-electrospray ionization mass spectrometry for hemoglobin variants analysis

On-line capillary isoelectric focusing (CIEF)-electrospray ionization mass spectrometry (ESIMS) as a two-dimensional separation system is employed for high-resolution analysis of hemoglobin variants A, C, S, and F. The effects of moving ionic boundary inside the CIEF capillary and MS scan rate on the separation resolution and mass detection of hemoglobin variants are investigated. The formation of a moving ionic boundary due to the replacement of background electrolyte counterions with sheath liquid counterions can be minimized by combining cathodic mobilization with a gravity-induced hydrodynamic flow. Hemoglobin variants F and A, with a pI difference of 0.05 pH unit, are almost baseline resolved and identified in CIEF-ESIMS. The concentration detection limit for each hemoglobin variant is in the range of 10(-)(8) M, comparable to that obtained in two-dimensional gel electrophoresis using silver staining. Initial preconcentration during the focusing step and the use of single-ion monitoring scan mode are responsible for improving detection limits.

Decreased risk of graft failure with maternal liver transplantation in patients with biliary atresia

The presence of maternal cells in offspring may promote tolerance to noninherited maternal antigens (NIMAs). Children with biliary atresia (BA) have increased maternal cells in their livers, which may impact tolerance. We hypothesized that patients with BA would have improved outcomes when receiving a maternal liver. We reviewed all pediatric liver transplants recorded in the SRTR database from 1996 to 2010 and compared BA and non-BA recipients of maternal livers with recipients of paternal livers for the incidences of graft failure and retransplantation. Rejection episodes after parental liver transplantation were examined for patients transplanted at our institution. BA patients receiving a maternal graft had lower rates of graft failure compared to those receiving a paternal graft (3.7% vs. 10.5%, p = 0.02) and, consequently, fewer episodes of retransplantation (2.7% vs. 7.5%, p = 0.04). These differences were not seen among non-BA patients or among BA patients who received female deceased donor grafts. In patients transplanted at our institution, paternal liver transplantation was associated with an increased incidence of refractory rejection compared to maternal liver transplantation only in BA. Our data support the concept that maternal cells in BA recipients promote tolerance to NIMAs and may be important in counseling BA patients who require liver transplantation.

The increase in sympathetic nerve density in the atrium facilitates atrial fibrillation in patients with rheumatic heart disease

BACKGROUND

Atrial fibrillation (Af) is frequently observed in patients with rheumatic heart disease (RHD). The hyperactivity of autonomic nervous system is known to contribute to the occurrence of Af in RHD patients. This study investigated the association between the autonomic density and the risk of Af in RHD patients.

METHODS

Seventy-five patients were enrolled: (1) RHD patients with Af (N = 25, Group 1); (2) RHD patients without Af (N = 25, Group 2); (3) congenital heart disease patients without Af (N = 25, Group 3). The baseline characteristics and the blood concentrations of renin, C-reaction protein and angiotensin II were collected from all patients. The tissues were obtained from the right atrial appendage during the open-heart surgery and then stained using immunohistochemical methods with autonomic antibodies.

RESULTS

The sympathetic nerve density was significantly higher in RHD patients with Af than RHD patients without Af and congenital heart disease patients, both endocardially and epicardially. The parasympathetic nerve density did not show significant difference among the three groups. The left atrial diameter was larger in RHD patients with Af than the other two groups. The blood concentrations of renin and angiotensin II were higher in RHD patients with Af than the other two groups. The erythrocyte sedimentation rate and blood concentrations of C-reaction protein did not show significant change among the three groups.

CONCLUSION

This study provided direct evidence of the increase in sympathetic nerve density in atrium in patients with RHD. This phenomenon may be associated with the development of Af in RHD patients.

Exacerbated pulmonary arterial hypertension and right ventricular hypertrophy in animals with loss of function of extracellular superoxide dismutase

Studies have demonstrated that increased oxidative stress contributes to the pathogenesis and the development of pulmonary artery hypertension (PAH). Extracellular superoxide dismutase (SOD3) is essential for removing extracellular superoxide anions, and it is highly expressed in lung tissue. However, it is not clear whether endogenous SOD3 can influence the development of PAH. Here we examined the effect of SOD3 knockout on hypoxia-induced PAH in mice and a loss-of-function SOD3 gene mutation (SOD3(E124D)) on monocrotaline (40 mg/kg)-induced PAH in rats. SOD3 knockout significantly exacerbated 2 weeks of hypoxia-induced right ventricular (RV) pressure and RV hypertrophy, whereas RV pressure in SOD3 knockout mice under normoxic conditions is similar to wild-type controls. In untreated control rats at age of 8 weeks, there was no significant difference between wild-type and SOD3(E124D) rats in RV pressure and the ratio of RV weight:left ventricular weight (0.25±0.02 in wild-type rats versus 0.25±0.01 in SOD3(E124D) rats). However, monocrotaline caused significantly greater increases of RV pressure in SOD3(E124D) rats (48.6±1.8 mm Hg in wild-type versus 57.5±3.1 mm Hg in SOD3(E124D) rats), of the ratio of RV weight:left ventricular weight (0.41±0.01 versus 0.50±0.09; P<0.05), and of the percentage of fully muscularized small arterioles in SOD3(E124D) rats (55.2±2.3% versus 69.9±2.6%; P<0.05). Together, these findings indicate that the endogenous SOD3 has no role in the development of PAH under control conditions but plays an important role in protecting the lung from the development of PAH under stress conditions.

Production of Y‐Ba‐Cu‐0 Superconducting Thin Films by an Aerosol Chemical Vapor Deposition Process

Thin film production by aerosol deposition is a simple, non‐vacuum method, which under certain conditions of the process parameters, can be considered as a chemical vapor deposition (CVD) process. In this paper we describe the formation of superconducting thin films by aerosol deposition in the CVD regime by using metal‐organic precursors. The best results were obtained with the metal β‐diketonates of Y, Ba and Cu dissolved in butylacetate. This solution was nebulized and sprayed on a heated Si‐substrate with a Zr02‐buffer layer at a temperature of 450 C. After deposition a final heat treatment at a temperature of 800 C was applied. The resulting superconducting film has a Tc>2ero of 75 K.

Slow cardiac myosin regulatory light chain 2 (MYL2) was down-expressed in chronic heart failure patients

BACKGROUND

Genetic studies have shown that many slow cardiac myosin regulatory light chain 2 (MYL2) gene mutations can cause hypertrophic cardiomyopathy, which is one of the most common causes of heart failure (HF). But until now there has been no pathological or histological evidence that MYL2 may be associated with HF development. Recent microarray studies indicated that myosin heavy chain expression changed in the pathological process of HF. Because MYL2 is a regulatory component of myosin heavy polypeptide, the role of MYL2 protein in HF needs to be studied.

HYPOTHESIS

The level of expression of MYL2 may change in the heart tissue of patients with chronic HF.

METHODS

We collected 28 human right auricle samples, 16 from chronic HF patients and 12 from healthy control subjects. Immunohistochemistry was carried out to observe the tissue-expression pattern of the MYL2 protein and Western blot methods were performed to quantify the relative MYL2 expression level.

RESULTS

In chronic HF patients, the MYL2 protein level decreased significantly compared with normal controls (t test P < 0.05). Among the 16 HF patients, MYL2 expression in the severe HF group (New York Heart Association [NYHA] class III or IV) was even lower than that of the moderate HF group (NYHA class II) (t test P < 0.05).

CONCLUSIONS

MYL2 was down-expressed in HF tissues, and our findings suggested that MYL2 may play a role in the development and progression of chronic HF.

WITHDRAWN: Inhibition of NADPH oxidase up-regulates connexin 43 and ameliorates electrical remodeling in rabbits with heart failure

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.biomag.2010.08.001. The duplicate article has therefore been withdrawn.

The feasibility of using magnetic nanoparticles modified as gene vector

OBJECTIVE

To evaluate the feasibility of using magnetic nanoparticles (MNPs) as gene vector and the effect of magnetic field on efficiency of transfection.

METHODS

Magnetic nanoparticles were prepared by controlling some chemical reaction parameters through a partially reduction precipitation method with ferric chloride aqueous solution as precursor material. The surface of particles was modified by polyethyleneimine (PEI) agents. The appearance, the size distribution, structure and phase constitute of MNPs were characterized by Transmission electron microscope (TEM), X-ray diffraction (XRD); the potential of absorbing DNA of MNPs was analysed by electrophoresis. Transfection was determined by delivering reporter gene, PGL2-control encoding luciferase, to different cell lines using MNPs-PLL as vector. The effect of magnetic field on the efficiency of transfection was determined using Nd-Fe-B permanent magnet.

RESULTS

Foreign gene could be delivered to various cell lines by MNPs-PLL and expressed with high efficiency but the transfection efficiency and time course varied in the different cell lines studied. Magnetic field could enhance the efficiency of transfection by 5-10 fold.

CONCLUSION

MNPs- PLL can be used as a novel non-viral gene vector in vitro, which offers a basis for gene delivery in vivo.

Isolation and characterization of a sea cucumber fucoidan-utilizing marine bacterium

AIMS

To isolate a fucoidan-utilizing strain from seawater for sea cucumber fucoidan degradation.

METHODS AND RESULTS

The utilization of sea cucumber fucoidan was monitored by H(2)SO(4)-phenol assay for neutral sugar. The bacterium CZ1127 was isolated from seawater and shown to have a relatively large maximum fucoidan-utilizing rate of 81.5%. CZ1127 was confirmed to belong to the family Flavobacteriaceae by 16S rDNA and physiological analyses. This strain has an ability to utilize fucoidans extracted from various sea cucumbers to different degrees. Both extracellular and intracellular enzymes of CZ1127 could degrade sea cucumber fucoidan, as confirmed by high-performance size exclusion chromatography. The M(r) of sea cucumber fucoidan could be reduced from 792.6 kDa to at least 3.7 kDa by the crude intracellular enzyme of this strain.

CONCLUSIONS

The marine bacterial strain CZ1127, which belongs to the family Flavobacteriaceae, was found to utilize various sea cucumber fucoidans and furthermore showed promise in sea cucumber fucoidan enzymatic degradation and oligosaccharide preparation.

SIGNIFICANCE AND IMPACT OF THE STUDY

The finding of a novel source can be applied in sea cucumber fucoidan enzymatic degradation. Furthermore, it is the first definite report of a bacterial strain that can utilize the fucoidans from various sea cucumbers.

Partial cancerous changes eventually developing into superficial spreading cancer over 18 months

In this report, we describe a patient presenting with the superficial spreading type of early gastric cancer (egc) accompanied by cancerous ulcers. Disease progression and treatment outcome are discussed. After symptoms persisted for more than 1 year, the patient underwent total gastrectomy with D2 lymph node dissection. The patient was diagnosed with superficial spreading cancer (ssc), accompanied by an extensive iic lesions. The progression of this patient suggests that the co-occurrence of cancerous ulcers may contribute to egc development to some extent. As is known, egc often develops into advanced gastric cancer with time. However, in our case, we observed a process during which partial cancerous changes developed into ssc over 18 months. Superficial spreading cancer should be considered an egc variant, which may have the ability to spread superficially along the stomach wall without invading the muscularis propria. But we speculate that, if gene expression changes for some reason, the malignant ssc cells may acquire the ability to grow deeply into the stomach wall. Eventually, Borrmann type iv gastric cancer may develop.

Structural studies of the N-terminus of Connexin 32 using 1H NMR spectroscopy

The amino terminus of gap junction proteins, connexins, plays a fundamental role in voltage gating and ion permeation. We have previously shown with (1)H NMR that the structure of the N-terminus of a representative connexin molecule contains a flexible turn around glycine 12 [P.E. Purnick, D.C. Benjamin, V.K. Verselis, T.A. Bargiello, T.L. Dowd, Arch. Biochem. Biophys. 381 (2000) 181-190] allowing the N-terminus to reside at the cytoplasmic entry of the channel forming a voltage-sensor. Previous functional studies or neuropathies have shown that the mutation G12Y and G12S form non-functional channels while functional channels are formed from G12P. Using 2D (1)H NMR we show that similar to G12, the structure of the G12P mutant contains a more flexible turn around residue 12, whereas the G12S and G12Y mutants contain tighter, helical turns in this region. These results suggest an unconstrained turn is required around residue 12 to position the N-terminus within the pore allowing the formation of the cytoplasmic channel vestibule, which appears to be critical for proper channel function.

Identification of tumor stem-like cells in a mouse myeloma cell line

We used colony formation assay in the soft agar media or the serum-free media, the methods of identifying BrdU-label-retaining cells and the SP cells as well as the tumorigenicity test in BALB/c mice, respectively, to analyze tumor stem like cells in the SP2/0 cell line. The results showed that a few SP2/0 cells were capable of forming colonies in the soft agar media, contained BrdU-label-immortal strand in the SP2/0 cell line. The SP2/0 cells in the serum-free media gained higher tumorigenicity in the BALB/c mice than the SP2/0 cells cultivated in the complete media did. Overall, only a few of the SP2/0 cells were found to possess the characteristics of tumor stem-like cells, such as high proliferative potency, more self-renewal and stronger tumorigenesis, or greater similarity to the tumor stem cells (TSCs) traits. The biology of tumor stem-like cells contributes to the identification of molecular targets important for future tumor therapy.