[Valproic acid activates autophagy in multiple myeloma cell lines RPMI8226 and U266]

目的

探讨丙戊酸钠对多发性骨髓瘤（MM）细胞株RPMI8226和U266细胞自噬的影响。

方法

丙戊酸钠处理RPMI8226和U266细胞，吖啶橙染色后采用荧光显微镜观察细胞自噬形态学变化，MTT法检测细胞增殖抑制的变化，流式细胞术检测细胞凋亡，实时定量PCR（RT-PCR）和Western Blot法检测细胞自噬相关因子LC3、Beclin1的变化。

结果

荧光显微镜观察到RPMI8226及U266细胞存在基础水平的自噬现象，丙戊酸钠作用后能够诱导细胞自噬增多；MTT法检测结果显示丙戊酸钠对细胞增殖抑制具有时间及浓度依赖性，作用24 h后半数抑制浓度分别为（12.03±0.23）mmol/L和（10.16±0.37) mmol/L。8 mmol/L丙戊酸钠作用24 h后，RPMI8226、U266细胞LC3 mRNA表达水平（22.45±0.07、0.06±0.02）、Beclin1 mRNA表达水平（283.09±17.3、1.53±0.01）与空白对照组（1.00± 0.00、1.00±0.00）比较，差异均有统计学意义（P值均<0.05）。随着丙戊酸钠浓度增加和作用时间延长，LC3、Beclin1蛋白表达水平逐渐增加，LC3Ⅰ向LC3Ⅱ的转化率逐渐升高。

结论

RPMI8226和U266细胞中存在基础水平的自噬现象，丙戊酸钠对MM细胞的自噬有激活作用，这可能是丙戊酸钠治疗MM的机制之一。

Association of CD36 expression and polymorphism with serum biochemical indices in Cherry Valley duck

Cluster of differentiation 36 (CD36) plays a crucial role in lipid sensing, innate immunity, atherogenesis, and glycolipid metabolism. This aims of this study were to delineate the CD36 mRNA expression profile in 16 duck tissues using relative quantitative real-time PCR and to screen single nucleotide polymorphisms (SNPs) in the duck CD36 gene by PCR-single strand conformation polymorphism and DNA direct sequencing. In addition, this study investigated CD36 gene expression, genetic variation, and their effect on serum biochemical indices in duck. The results showed that CD36 mRNA was expressed in all tissues, and was highly specific to the pituitary and large intestine, and to subcutaneous and abdominal fat. Furthermore, three genotypes of the SNP g.476593 T > C in exon 9 of the duck CD36 gene were identified: MM, MN, and NN. The dominant genotype and allele were MM and M, with frequencies of 0.453 and 0.643, respectively. The genotype distributions deviated from Hardy-Weinberg equilibrium (P < 0.05) and achieved moderate levels of polymorphism in ducks. Correlation results showed that CD36 mRNA was significantly negatively correlated with triglycerides (P < 0.05), and significantly positively correlated with total protein, globulin, low-density lipoprotein cholesterol, and total cholesterol (P < 0.01). All serum biochemical indices measured, with the exception of triglycerides, in birds with the NN genotype were significantly higher than those in birds with the MM genotype. These findings demonstrated that CD36 might be an important genetic marker for the selection of lipid metabolism and meat quality traits in ducks.

Detection of Piwi-interacting RNAs based on sequence features

Piwi-interacting RNAs (piRNAs) are a class of small non-coding RNAs. Distinguishing piRNAs from other non-coding RNAs is important because of their important role in the physiological regulation of spermatogenesis, genome protection from transposons, and regulation of mRNAs and long non-coding RNAs. Few computational studies have addressed piRNAs detection, and both effectiveness and efficiency of piRNA detection tools require improvement. In this study, a piRNA detection method based on sequence features and a support vector machine was developed. Four types of features are proposed: weighted k-mer, weighted k-mer with wildcards, position-specific base, and piRNA length. The piRNA sequences from human, mouse, rat, and drosophila were respectively used in this experiment. Compared to existing algorithms, the proposed method provides a better balance between precision and sensitivity (both are approximately 90%), and although these values were slightly slower than those obtained using the piRNA annotation approach, the proposed method was four-fold faster than piRPred and 229-fold faster than piRNA predictor.

Genetic analysis of floral organ size in broccoli × cabbage via a mixed inheritance model of a major gene plus polygene

Broccoli and cabbage are important vegetable crops that produce hybrid seeds after insect pollination; the size of floral organs is crucial for this process. To investigate the genetic characteristics of floral organ sizes (corolla width, petal length and width, and lengths of stamen, anther, style, and stigma) and to improve the flower size and breeding efficiency of broccoli, we used multi-generation analysis of a major gene plus polygene model. Six populations obtained from a broccoli inbred line 93219 (small floral organs) and cabbage inbred line 195 (large floral organs) were used for the analysis. Corolla and petal width and stamen and anther length were controlled by the additive-dominance-epistasis polygene model. The heritability of these traits in BC1, BC2, and F2 generations was high (72.80-93.76%). Petal and stigma length were governed by the two major genes of additive-dominance-epistasis effects plus additive-dominance polygene model; the major gene heritability in the F2 generation were 79.17 and 65.77%, respectively. Style length was controlled by one major gene of additive-dominance effects plus additive-dominance-epistasis polygene model; the major gene heritability in BC1, BC2, and F2 were 40.60, 10.35, and 38.44%, respectively; the polygene heritability varied from 41.85 to 68.44%. Our results provide important genetic information for breeding, which could guide improvement of flower-related traits and lay the foundation for quantitative trait loci mapping of the flower-size traits in Brassica.

[Protective effect of compound bismuth and magnesium granules on aspirin-induced gastric mucosal injury in rats]

OBJECTIVE

To investigate the protective effect of compound bismuth and magnesium granules on aspirin-induced gastric mucosal injury in rats and its possible mechanism.

METHODS

Acute gastric mucosal injury model was developed with intraperitoneal injection of aspirin in Wistar rats. The rats were divided into normal control group, injury group, sucralfate protection group, compound bismuth and magnesium granules protection group and its herbal components protection group(each group 12 rats). In the protection groups, drugs as mentioned above were administered by gavage before treated with intraperitoneal injection of aspirin. To evaluate the extent of gastric mucosal injury and the protective effect of drugs, gastric mucosal lesion index, gastric mucosal blood flow, content of gastric mucosal hexosamine, prostaglandins (PG), nitric oxide(NO), tumor necrosis factor (TNF), and interleukin (IL) -1, 2, 8 were measured in each group, and histological changes were observed by gross as well as under microscope and electron microscope.

RESULTS

Contents of hexosamine, NO, and PG in all the protection groups were significantly higher than those in the injury group (all P<0.01), and content of NO in the compound bismuth and magnesium granules group was significantly higher than that in the sucralfate group ((11.29±0.51) vs(10.80±0.36)nmol/ml, P<0.05). The gastric mucosal lesion index, contents of TNF, and IL-1, 2, 8 were significantly lower in all the protection groups than in the injury group (all P<0.01), and contents of IL-2 and IL-8 in the compound bismuth and magnesium granules group were significantly lower than those in the sucralfate group ((328.17±6.56) vs(340.23±8.05)pg/ml, P<0.01; (170.82±7.31) vs(179.31±7.80)pg/ml, P<0.05). Tissue injury and inflammatory reaction in all the protection groups were obviously mitigated compared with the injury group.

CONCLUSION

Compound bismuth and magnesium granules and its herbal components may have significant protective effect on aspirin-induced gastric mucosal injury.

Association of CRTC2 gene polymorphisms with growth and meat quality traits of Qinchuan cattle

Growth and meat quality traits play important roles in the evaluation of cattle productivity and are influenced by genetic and environmental factors. CRTC2 is a recently discovered gene related to obesity that may influence fat deposition. The aim of the current study was to detect polymorphisms of bovine CRTC2 and explore their relationships to growth and meat quality in Qinchuan cattle. Three single nucleotide polymorphisms (SNPs); g.3001 C>T; g.3034 G>A; and g.3467 T>C, were identified from sequencing results of 422 Qinchuan cattle. The genotypic distributions of both g.3034 G>A and g.3467 T>C mutations were in agreement with Hardy-Weinberg equilibrium, (P < 0.05), while the T3001C mutation was not (P > 0.05), based on χ(2) test analysis. The SNPs g.3001 C>T and g.3034 G>A are missense mutations (Ser/Phe and Ser/Thr respectively). Additionally, SNPs g.3034 G>A and g.3467 T>C showed a medium polymorphism level (0.25 < PIC< 0.50), whereas g.3001 C>T showed a low polymorphism level (PIC < 0.25). These three SNPs were significantly associated with several growth and meat quality traits in the Qinchuan cattle population (P < 0.05 or P < 0.01). Collectively, these results demonstrate that CRTC2 is involved in the regulation of cattle growth and meat quality, and suggest that CRTC2 is a potential candidate gene for marker-assisted selection in future breeding development programs for Qinchuan cattle.

Association of novel polymorphisms of forkhead box L2 and growth differentiation factor-9 genes with egg production traits in local Chinese Dagu hens

Transcription factor forkhead box L2 (FOXL2) and growth differentiation factor-9 (GDF9) genes have critical roles in the regulation of hen ovarian development. In the present study, these genes were explored as possible molecular markers associated with BW, hen-housed egg production, and egg weight in Chinese Dagu hens. Samples were analyzed using the PCR-single strand conformation polymorphism (PCR-SSCP) technique followed by sequencing analysis, and two novel single nucleotide polymorphisms (SNPs) were identified within these candidate genes. Among them, an A/G transition at base position 238 in the coding region of the FOXL2 gene and a G/T transversion at base position 1609 in exon 2 of the GDF9 gene were found to be polymorphic and named SNPs A238G and G1609T, respectively. The SNP A238G (FOXL2) leads to a nonsynonymous substitution (isoleucine77-to-valine), and when the 360 Dagu hen samples were divided into genotypes AA and AB, allele A was found to be present at a higher frequency. Furthermore, the AA genotype correlated with significantly higher hen-housed egg production at 30, 43, 57, and 66 wk of age and with a higher egg weight at 43 wk (P<0.05). For the SNP G1609T (GDF9), the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher hen-housed egg production and a higher egg weight (P<0.05). Moreover, four haplotypes were reconstructed based on these two SNPs, with the AATC haplotype found to be correlated with the highest hen-housed egg production at 30 to 66 wk of age and with higher egg weights at 43 wk (P<0.05). Collectively, the two SNPs identified in this study might be used as possible genetic molecular markers to aid in the improvement of egg production traits in chicken breeding.

New insights into implication of the SLIT/ROBO pathway in the prehierarchical follicle development of hen ovary

The SLIT/Roundabout (ROBO) pathway is involved in follicle development of mammalian ovary, and 2 secreted hormones activin A and inhibin A have potential roles in modulation of the SLIT/ROBO system, but the related actions remain poorly understood in bird. The aims of the present study were to examine the spatial and temporal expression of the SLIT ligand genes (SLIT1, SLIT2, and SLIT3) and their receptor ROBO1, ROBO2, ROBO3, and ROBO4 genes in various-sized prehierarchical follicles during hen ovary development and the effects of activin A and inhibin A on the expression of these genes in the cultured hen follicles. Our result demonstrated that the transcripts of the 3 SLIT genes were highly expressed in the developing follicles and expression patterns of the SLIT transcripts were different from those of ROBO genes detected by real-time quantitative reverse transcriptase PCR. Both SLIT and ROBO transcripts were predominantly expressed in oocytes and granulosa cells from the prehierarchichal follicles examined by in situ hybridization. The localization for SLIT and ROBO proteins was revealed by immunohistochemistry similar to the spatial distribution of their transcript. In cultured follicles (4 to 8 mm in diameter), the expression levels of SLIT and ROBO members are hormonally regulated by activin A (10 ng/mL) and/or inhibin A (20 ng/mL) after treatment for 24 h. However, the expression of only SLIT2, SLIT3, and ROBO3 mRNA presented a directly opposite response to activin A and inhibin A hormones. These results indicate that SLIT/ROBO pathway is implicated in the prehierarchical follicular development of the hen ovary by an intrafollicular autocrine and/or paracrine action, and is influenced by activin A and inhibin A hormones.

Riga-Fede disease in a child

Riga-Fede disease (RFD) was initially described as a benign ulceration of the lingual frenum or tongue of infants, most commonly resulting from repetitive trauma by natal teeth. However, similar clinical manifestations can also be found in children with repetitive tongue-thrusting habits or certain neurological disorders. This report describes an unusual case of RFD in a 6-year-old Chinese boy. The lesion appeared as an ulcer on the anterior ventral surface of the child's tongue, and was caused by a repetitive tongue-thrusting habit. After eliminating the source of repetitive trauma and starting concurrent use of therapeutic drugs for 1 week, the lesion healed completely.

Effect of phosphatidylserine on memory in patients and rats with Alzheimer's disease

The aim of this study was to investigate the effect of phosphatidylserine (PS) on memory of patients and rats with Alzheimer's disease (AD). In total, 57 AD patients were recruited from our hospital, and were divided into two groups: 25 in the control group and 32 in the observation group. Next, 300 mg/d of PS was given to the rats in the observation group for 12 continuous weeks based on the control group. AD rats were divided into three groups: control group, PS 30 mg/kg group, and PS 15 mg/kg group. Learning memory ability and free radical levels in the brain were detected after treatment. In AD patients, vocabulary and picture matching scores in the two treatment groups increased after treatment (P < 0.05). Moreover, the scores in the treated group were significantly greater than the control group (P < 0.05). In AD rats, PS treatment reduced the escape latent period of AD rats, increased SOD and OH(-), and decreased acetylcholinesterase levels (P < 0.05). Compared with PS 15 mg/kg, PS 30 mg/kg group was significantly more efficacious (P < 0.05). Compared with the AD model group, hippocampal cells showed normal arrangement, karyopyknosis decreased, and the pathological changes in the two PS groups were considerable. In conclusion, PS decreased cholinesterase, improved memory, and improved hippocampal inflammation injury in AD brains by increasing SOD and OH(-) levels.

Molecular variation of Sporisorium scitamineum in Mainland China revealed by internal transcribed spacers

Sugarcane smut caused by the fungus Sporisorium scitamineum is a worldwide disease and also one of the most prevalent diseases in sugarcane production in mainland China. To study molecular variation in S. scitamineum, 23 S. scitamineum isolates from the 6 primary sugar-cane production areas in mainland, China (Guangxi, Yunnan, Guangdong, Hainan, Fujian, and Jiangxi Provinces), were assessed using internal transcribed spacer (ITS) methods. The results of ITS sequence analysis showed that the organisms can be defined at the genus level, including Ustilago and Sporisorium, and can also differentiate between closely related species. This method was not suitable for phylogenetic relationship analysis of different S. scitamineum isolates and could not provide support regarding their race ascription at the molecular level. The results of the present study will be useful for studies examining the molecular diversity of S. scitamineum and for establishing a genetic foundation for their pathogenicity differentiation and new race detection. In addition, our results can provide useful information for the pathogen selection principle in sugarcane smut resistance breeding and variety distribution.

Identification of smut-responsive genes in sugarcane using cDNA-SRAP

Sugarcane smut, caused by the fungus Sporisorium scitamineum, is one of the main diseases that affect sugarcane worldwide. In the present study, the cDNA-SRAP technique was used to identify genes that are likely to be involved in the response of sugarcane to S. scitamineum infection. In total, 21 bands with significant differential expression during cDNA-SRAP analysis were cloned and sequenced. Real-time qPCR confirmation demonstrated that expression of 19 of these 21 differential bands was consistent with the expression observed during cDNA-SRAP analysis, with a deduced false positive rate of 9.5%. Sequence alignment indicated that 18 of 19 differentially expressed genes showed homologies from 19% to 100% to certain genes in GenBank, including the following genes: topoisomerase (EU048780), ethylene insensitive (EU048778), and tetraspanin (EU048770). A real-time qPCR assay showed that during 0-72 h after pathogen infection, expression of the topoisomerase and the ethylene insensitive genes was upregulated, whereas expression of the tetraspanin gene was downregulated, identical to the expression patterns observed under salicylic acid treatment. Therefore, all three genes are thought to play a role during S. scitamineum challenge, but with different functions. To our knowledge, this is the first report on the application of cDNA-SRAP in differential gene expression analysis of sugarcane during a sugarcane-S. scitamineum interaction. The results obtained also contribute to a better understanding of the molecular mechanisms associated with sugarcane-S. scitamineum interactions.

Monolayer PtSe₂, a New Semiconducting Transition-Metal-Dichalcogenide, Epitaxially Grown by Direct Selenization of Pt

Single-layer transition-metal dichalcogenides (TMDs) receive significant attention due to their intriguing physical properties for both fundamental research and potential applications in electronics, optoelectronics, spintronics, catalysis, and so on. Here, we demonstrate the epitaxial growth of high-quality single-crystal, monolayer platinum diselenide (PtSe2), a new member of the layered TMDs family, by a single step of direct selenization of a Pt(111) substrate. A combination of atomic-resolution experimental characterizations and first-principle theoretic calculations reveals the atomic structure of the monolayer PtSe2/Pt(111). Angle-resolved photoemission spectroscopy measurements confirm for the first time the semiconducting electronic structure of monolayer PtSe2 (in contrast to its semimetallic bulk counterpart). The photocatalytic activity of monolayer PtSe2 film is evaluated by a methylene-blue photodegradation experiment, demonstrating its practical application as a promising photocatalyst. Moreover, circular polarization calculations predict that monolayer PtSe2 has also potential applications in valleytronics.

Identifying patients with chronic hepatitis B at high risk of type 2 diabetes mellitus: a cross-sectional study with pair-matched controls

BACKGROUND

The presence of diabetes mellitus (DM) is associated with increased liver morbidity and mortality risk in patients with chronic hepatitis B (CHB). Aim of this study was to identify factors associated with type 2 diabetes mellitus (T2DM) in CHB patients.

METHODS

A cross-sectional study with pair-matched controls was conducted in Nantong Third People's Hospital, Nantong University, China. From January 2008 to December 2012, a total of 1783 CHB patients were screened for study subjects, among whom 207 patients with T2DM were enrolled as cases and 207 sex- and age-matched non-DM patients as controls. Demographic, anthropometric, lifestyle, clinical, and laboratory data were obtained from each subject.

RESULTS

In the univariate model, thirteen variables showed marked differences between the DM group and non-DM group. Patients with longer duration of CHB (≥15 years) and alcoholic steatosis showed the highest likelihood of T2DM (odds ratio = 5.39 and 4.95; 95% confidence intervals 2.76-10.53 and 1.65-14.91). In the multivariate adjusted analysis, three CHB-related factors, namely high viral load, long duration of illness, and presence of cirrhosis, contributed to substantially increase the likelihood of T2DM, in addition to the other five risk factors including family history of DM, low education level, elevated triglycerides (TG), gamma-glutamyl transferase (GGT) levels, and presence of alcoholic steatosis.

CONCLUSIONS

Our findings suggest that high viral load, long duration of CHB, presence of cirrhosis, alcoholic steatosis and several other factors may be potential risk factors for development of T2DM in CHB patients. It is of vital importance to monitor glucose in high-risk CHB patients and aggressively intervene on modifiable risk factors.

Pathological hypertrophy reverses β2-adrenergic receptor-induced angiogenesis in mouse heart

β-adrenergic activation and angiogenesis are pivotal for myocardial function but the link between both events remains unclear. The aim of this study was to explore the cardiac angiogenesis profile in a mouse model with cardiomyocyte-restricted overexpression of β₂-adrenoceptors (β₂-TG), and the effect of cardiac pressure overload. β₂-TG mice had heightened cardiac angiogenesis, which was essential for maintenance of the hypercontractile phenotype seen in this model. Relative to controls, cardiomyocytes of β₂-TGs showed upregulated expression of vascular endothelial growth factor (VEGF), heightened phosphorylation of cAMP-responsive-element-binding protein (CREB), and increased recruitment of phospho-CREB, CREB-binding protein (CBP), and p300 to the VEGF promoter. However, when hearts were subjected to pressure overload by transverse aortic constriction (TAC), angiogenic signaling in β₂-TGs was inhibited within 1 week after TAC. β₂-TG hearts, but not controls, exposed to pressure overload for 1–2 weeks showed significant increases from baseline in phosphorylation of Ca²⁺/calmodulin-dependent kinase II (CaMKIIδ) and protein expression of p53, reduction in CREB phosphorylation, and reduced abundance of phospho-CREB, p300 and CBP recruited to the CREB-responsive element (CRE) site of VEGF promoter. These changes were associated with reduction in both VEGF expression and capillary density. While non-TG mice with TAC developed compensatory hypertrophy, (₂-TGs exhibited exaggerated hypertrophic growth at week-1 post-TAC, followed by LV dilatation and reduced fractional shortening measured by serial echocardiography. In conclusion, angiogenesis was enhanced by the cardiomyocyte (₂AR/CREB/VEGF signaling pathway. Pressure overload rapidly inhibited this signaling, likely as a consequence of activated CaMKII and p53, leading to impaired angiogenesis and functional decompensation.

Rapid Solidification and Magnetic Properties of (Fe,Co)-(Fe,Co)17Gd2 Pseudo-Binary Eutectic Alloys

The (Fe,Co)-(Fe,Co)17Gd2 pseudo-binary eutectic system has been determined by investigating phase compositions on the analysis of DSC, EDS and XRD. The rapid solidification of Gd7.3Fe30.56Co62.14, Gd9Fe30Co61 and Gd9.63Fe29.79Co60.58 ternary alloys is realized by single roller techniques. With a rising cooling rate, the equiaxed zone near the roller surface expands inwards. For Gd7.3Fe30.56Co62.14 hypoeutectic alloy ribbons, the feathery irregular eutectic zone shrinks and the grains (Fe,Co) near the free surface are refined. (Fe,Co) equiaxed dendrites plus the radial, irregular eutectic ultimately fill in the ribbon at the maximum cooling rate. For Gd9Fe30Co61 near-eutectic alloy ribbons, the growth direction of irregular eutectics near the free surface becomes more and more perpendicular to the surface, and finally the whole ribbons are occupied by the fine, irregular eutectic. The dendritic spacing of the (Fe,Co)17Gd2 phase which grows from the roller surface to the free surface in Gd9.63Fe29.79Co60.58 alloy ribbons becomes smaller. The grain size of the (Fe,Co)17Gd2 dendrite and the fraction of (Fe,Co) soft phase in alloy ribbons, which determine coercivity in the pseudo-binary eutectic system, vary with the increase of the cooling rate. Of the three alloys, the Gd9Fe30Co61 alloy has the best hard magnetic properties at Vr = 20 m/s; the maximum coercivity Hc is 431.34 Oe.

Genome-wide identification and expression analysis of the CPP-like gene family in soybean

Cysteine-rich polycomb-like protein (CPP-like) genes are a group of transcription factors with highly conserved cysteine-rich domains and are widely distributed in animals and plants, but do not present in yeast. Previous studies have shown that members of this family play important roles in the development of reproductive tissue and in the control of cell division in plants. In this study, whole genome identification of soybean CPP transcription factors was performed using bioinformatic methods. The results showed that there were 20 CPP transcription factors in the soybean genome, which encoded for 28 distinct CPP proteins. These transcription factors were distributed on 16 of 20 chromosomes. Phylogenetic relationship analysis showed that expression of CPP gene family members occurred before the differentiation of monocotyledons and dicotyledons. RNA-Seq analysis showed that 5 genes were highly expressed in all tissues, including Glyma10g39080, Glyma01g44670, Glyma101g66920, Glyma02g01540, and Glyma20g28740. One gene (Glyma14g14750) was specifically expressed in young leaves, while 2 genes (Glyma02g01540 and Glyma10g01580) were highly expressed in root nodules. Quantitative reverse transcriptase-polymerase chain reaction analysis revealed that the expression levels of most genes increased in the roots under high temperature stress. Our findings indicate that these genes are not only involved in growth and development, but also in the responses to high temperature stress in soybean roots.

Serial changes of mean platelet volume in relation to Killip Class in patients with acute myocardial infarction and primary percutaneous coronary intervention

INTRODUCTION

Mean platelet volume (MPV) is related to the reactivity of platelets. Among survivors of acute myocardial infarction (MI), greater MPV is known to be associated with impaired reperfusion and higher mortality. The aims of the study is to investigate the dynamic changes of MPV and the relation between MPV and cardiac function in patients with acute MI and received primary percutaneous coronary intervention (PCI).

MATERIALS AND METHODS

This retrospective cohort study included patients presented during January 2008 to March 2011 to Peking University Third Hospital with ST-segment elevation MI. All patients received successful PCI. MPV was measured serially, using a Sysmex XE2100 haematology analyser, from admission to day-7 after MI.

RESULTS

In 375 patients, MPV was at its highest value (10.2±1.0 fL) and correlated well with platelet distribution width (PDW, r=0.833, p<0.0001) at the admission, and then reduced by 16% within the 24 hours, together with marked weakening of its correlation with PDW. Patients with poorer ventricular function, estimated by high Killip Class (≥2, n=96), had higher MPV values at all-time points. By logistic regression model and after adjusting for related confounders, high MPV remained as an independent predictor of Killip Class ≥2 (OR 1.873, CI 95% 1.373-2.673, p=0.001). Clopidogrel pre-usage resulted in significant MPV reduction on admission.

CONCLUSIONS

MPV undergoes rapid and dynamic changes during the acute phase of MI, and was higher in patients with high Killip Class, suggesting a predictive value of MPV in ventricular dysfunction and clinical outcome of acute phase of MI.

[Activation of transcription factor NF-κB in a rat model of cardiac fibrosis induced by β-adrenoceptor stimulation]

OBJECTIVE

To establish a model of cardiac fibrosis induced by isoproterenol (ISO), the non-selective β adrenoceptor agonist, injected subcutaneously for 7 days in rats, and to observe changes of transcription factor NF-κB in the model.

METHODS

Male SD rats weighing 280-320 g were injected with ISO (0.25 mg/kg/d) subcutaneously for 7 days to induce cardiac fibrosis. The collagen volume fraction was determined by quantitative morphometry of picrosirius red stained left ventricular sections. Collagen types I/III and IL-6 mRNA expressions were analyzed by real time PCR. The pathological changes of the heart were investigated by Hematoxylin and Eosin staining. NF-κB was localized by immunohistochemistry (IHC) and phosphorylated NF-κB levels were assessed by Western blot analysis.

RESULTS

Compared with the controls, ISO significantly elevated the sirius red stained area and collagen volume fraction (12.01±1.644 vs. 0.95±0.067, P<0.001). Similarly, ISO increased the mRNA expressions of collagen Iand collagen III of the heart compared with the controls (10.51±0.47 vs. 0.98±0.02,P<0.001 for collagen I; 9.58±1.33 vs. 1.02±0.02, P<0.001 for collagen III). The number of nuclei was increased and nuclear accumulation was presented in myocardial tissue induced by ISO. The mRNA expression of IL-6 increased in ISO group (1.64±0.18 vs. 1.04±0.07, P<0.01). ISO induced NF-κB nuclear translocation, accompanied by an increase in phosphorylation of NF-κB (10.83±2.05 vs. 1.05±0.27, P<0.001).

CONCLUSION

We conclude that the model of cardiac fibrosis can be successfully induced by ISO injected subcutaneously for 7 days in rats and the activation of nuclear factor NF-κB increased by β-adrenoceptor stimulation.

[Establishment of a FVB/N mouse model of cardiac hypertrophy by isoprenaline]

OBJECTIVE

To investigate the condition of isoprenaline (ISO)-induced cardiac hypertrophy in the FVB/N mouse.

METHODS

ISO (30 mg/kg/d) was administered either by daily subcutaneous injection, or by continuous infusion via an implanted osmotic minipump. The mice in each mode of administration were randomly divided into two groups. For subcutaneous injection: the mice received ISO or saline through daily subcutaneous injection for 2 weeks. The mice for minipump: the mice received continuous infusion of ISO via an implanted osmotic minipump for 2 weeks, or received sham operation as the control to mimipump. The ratio of heart weight to tibia length (HW/TI), the diastolic left ventricular posterior wall thickness (dLVPW) were used to indicate cardiac hypertrophy. Interstitial fibrosis was examined with picrosirius red staining.

RESULTS

ISO (30 mg/kg/d) administered by daily subcutaneous injection did not lead to cardiac hypertrophy or fibrosis in the FVB/N mice, and 50% of the mice died before the end point. The mice receiving ISO via minipumps showed significant increase in HW/TI [(10.60±0.40 ) mg/mm vs. (7.93±0.19) mg/mm,P<0.001] and dLVPW [(0.87±0.03) mm vs. (0.68±0.06)mm,P=0.0116]. ISO administered via minipumps did not induce cardiac fibrosis. All the mice in this group survived to the end point.

CONCLUSION

ISO (30 mg/kg/d) administered by continuous infusion via a minipump for 2 weeks can lead to significant cardiac hypertrophy.

Magnetic bead and gold nanoparticle probes based immunoassay for β-casein detection in bovine milk samples

In this work, a double-probe based immunoassay was developed for rapid and sensitive determination of β-casein in bovine milk samples. In the method, magnetic beads (MBs), employed as supports for the immobilization of anti-β-casein polyclonal antibody (PAb), were used as the capture probe. Colloidal gold nanoparticles (AuNPs), employed as a bridge for loading anti-β-casein monoclonal antibody (McAb) and horseradish peroxidase (HRP), were used as the amplification probe. The presence of β-casein causes the sandwich structures of MBs-PAb-β-casein-McAb-AuNPs through the interaction between β-casein and the anti-β-casein antibodies. The HRP, used as an enzymatic-amplified tracer, can catalytically oxidize the substrate 3,3',5,5'-tetramethylbenzidine (TMB), generating optical signals that are proportional to the quantity of β-casein. The linear range of the immunoassay was from 6.5 to 1520ngmL(-1). The limit of detection (LOD) was 4.8ngmL(-1) which was 700 times lower than that of MBs-antibody-HRP based immunoassay and 6-7 times lower than that from the microplate-antibody-HRP based assay. The recoveries of β-casein from bovine milk samples were from 95.0% to 104.3% that had a good correlation coefficient (R(2)=0.9956) with those obtained by an official standard Kjeldahl method. For higher sensitivity, simple sample pretreatment and shorter time requirement of the antigen-antibody reaction, the developed immunoassay demonstrated the viability for detection of β-casein in bovine milk samples.

Artificial liver support system improves short- and long-term outcomes of patients with HBV-associated acute-on-chronic liver failure: a single-center experience

For patients with acute-on-chronic liver failure (ACLF), artificial liver support system (ALSS) may help prolong lifespan and function as a bridge to liver transplantation (LT), but data on its long-term benefit are lacking. We conducted this prospective, controlled study to determine the efficacy of ALSS and the predictors of mortality in patients with hepatitis B virus (HBV)-associated ACLF.From January 2003 to December 2007, a total of 234 patients with HBV-associated ACLF not eligible for LT were enrolled in our study. They were allocated to receive either plasma exchange centered ALSS plus standard medical therapy (SMT) (ALSS group, n=104) or SMT alone (control group, n=130). All the patients were followed-up for at least 5 years, or until death.At 90 days, the survival rate of ALSS group was higher than that of the control group (62/104 [60%] vs 61/130 [47%], respectively; P<0.05). Median survival was 879 days in the ALSS group (43% survival at 5 years) and 649 days in the control group (31% survival at 5 years, log-rank P<0.05). ALSS was found to be associated with favorable outcome of these patients by both univariate and multivariate analysis. Multivariate Cox regression analysis also revealed that lower serum sodium levels, higher grades of encephalopathy, presence of cirrhosis, hepatorenal syndrome, and higher model for end-stage liver disease scores were independent predictors for both 90-day and 5-year mortality due to ACLF.Our findings suggest that ALSS is safe and may improve the short- and long-term prognosis of patients with HBV-associated ACLF.

Isolation, molecular cloning, and characterization of a novel porcine lymphotoxin beta receptor gene

The lymphotoxin beta receptor (LTβR) is a member of the tumor necrosis factor family of receptors (TNFR). It plays a role in regulating lymphoid organogenesis and homeostasis of the immune system. In the present study, the full coding region of a putative LTβR gene of Sus scrofa was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned for the first time (accession Nos. JX457347 and AFU74012). In addition, analysis of the tissue expression profile was carried out via RT-PCR. The full-length coding region of porcine LTβR had 1266 nucleotides (molecular weight, 45.61 kDa; pI, 5.71) and encoded 421 amino acids. Bioinformatic prediction indicates that LTβR belongs to the TNFR superfamily and contains a TNFR domain. The sequence homology analysis revealed that the amino acid sequences of S. scrofa LTβR had 82.9, 82.4, 81.3, 80.5, 78.7, 74.6, and 73.0% identity with those of Equus caballus, Canis lupus, Ailuropoda melanoleuca, Oryctolagus cuniculus, Bos taurus, Mus musculus, and Homo sapiens, respectively. The phylogenetic tree based on the amino acid sequences of LTβR from 8 species revealed that S. scrofa was more closely related to E. caballus, C. lupus, and A. melanoleuca. RT-PCR analysis showed that the porcine LTβR gene was differentially expressed (e.g., high, moderate, low, or nonexistent) in various tissues (e.g., prostate, pituitary, brainstem, and esophagus, respectively). This may be related to differences in the regulation of LTβR in the different tissues.

Echocardiographic assessment of β-adrenoceptor stimulation-induced heart failure with reduced heart rate in mice

1. Chronic injection with the β-adrenoceptor (β-AR) agonist isoproterenol (ISO) has been commonly used as an animal model of β-AR-induced cardiac remodelling and heart failure. This ISO-treated model usually exhibits significantly decreased conscious heart rate (HR). However, the HR in treatment groups is usually adjusted to the same levels by anaesthesia to assess cardiac geometry and function. In the present study, we report a method of echocardiographic assessment that represents the true cardiac geometry and function under conditions of ISO withdrawal. 2. Briefly, C57BL/6 mice were treated with 5 mg/kg per day ISO for 12 weeks. Cardiac geometry and function were assessed by high-resolution echocardiography in vehicle (saline) - and ISO-treated mice that were either conscious or anaesthetized using different concentrations of isoflurane. 3. The cardiac β-AR response was decreased in ISO-treated mice, as evidenced by markedly decreased conscious HR. Vehicle- and ISO-treated mice did not differ in terms of cardiac geometry or function when HR was adjusted to the same level (400 b.p.m.) in both treatment groups, but cardiac geometry and function did differ when a low (1%) rather than high (1.5% or 2%) isoflurane concentration was used to adjust HR. Furthermore, 3 day ISO withdrawal eliminated the difference in conscious HR between the two groups. In addition, the groups differed in cardiac geometry and function regardless of the isoflurane concentration used. 4. In conclusion, using isoflurane to decrease the HR of treated groups to the same level may mask left ventricular dysfunction in ISO-treated mice. Withdrawal of ISO eliminated the difference in basal HR between the ISO-treated and control groups on echocardiography, allowing a more accurate assessment of cardiac pathological and functional changes.