Effects of different salinity reduction intervals on osmoregulation, anti-oxidation and apoptosis of Eriocheir sinensis megalopa.

Eriocheir sinensis megalopa has a special life history of migrating from seawater to freshwater. In order to investigate how the megalopa adapt themselves to the freshwater environment, we designed an experiment to reduce the salinity of water from 30 ppt to 0 at rates of 30 ppt, 15 ppt, 10 ppt, and 5 ppt per 24 h to evaluate the effects of different degrees of hyposaline stress on the osmotic regulation ability and antioxidant system of the megalopa. Experimental results related to osmotic pressure regulation show that the gill tissue of megalopa in the treatment group of 30 ppt/24 h rapid reduction of salinity was damaged, while in the treatment group of 5 ppt/24 h it was intact. At the same time, the experiment also found that in each treatment group with different salinity reduction rates, compared with the control salinity, the NKA activity of megalopa increased significantly after the salinity was reduced to 20 ppt (p < 0.05). In addition, two genes involved in chloride ion transmembrane absorption have different expression patterns in the treatment groups with different salinity reduction rates. Among them, Clcn2 was significantly highly expressed only in the rapid salinity reduction intervals of 30 ppt/24 h and 15 ppt/24 h (p < 0.05). Slc26a6 was significantly highly expressed only in the slow salinity reduction intervals of 10 ppt/24 h and 5 ppt/24 h (p < 0.05). On the other hand, the results of antioxidant and apoptosis related experiments showed that in all treatment groups with different rates of salinity reduction, the activities of T-AOC, GSH-PX, and CAT basically increased significantly after salinity reduction compared to the control salinity. Moreover, the activities of T-AOC and CAT were significantly higher in the 10 ppt/24 h and 5 ppt/24 h treatment groups than in the 30 ppt/24 h and 15 ppt/24 h treatment groups. Finally, the experimental results related to apoptosis showed that the expression trends of Capase3 and Bax-2 were basically the same in the treatment groups with different salinity reduction rates, and their expressions were significantly higher in the 10 ppt/24 h and 5 ppt/24 h treatment groups than in the 30 ppt/24 h and 15 ppt/24 h treatment groups. In summary, the present study found that megalopa had strong hyposaline tolerance and were able to regulate osmolality at different rates of salinity reduction, but the antioxidant capacity differed significantly between treatment groups, with rapid salinity reduction leading to oxidative damage in the anterior gills and reduced antioxidant enzyme activity and apoptosis levels.

Correction to: Chlorinated and brominated organic pollutants in shellfish from the Yellow Sea and East China Sea.

The article Chlorinated and brominated organic pollutants in shellfish from the Yellow Sea and East China Sea, written by Ge Yin, Lillemor Asplund, Yanling Qiu, Yihui Zhou, Hua Wang, Zongli Yao, Jianbin Jiang and Åke Bergman.

Analysis of Morphological Characteristics and Origins of Idiopathic Premature Ventricular Contractions Under a 12-Lead Electrocardiogram in Children with Structurally Normal Hearts.

Up to 40% of healthy children have premature ventricular complexes or contractions (PVCs) detected with 24-hour Holter monitoring. We aimed to investigate the morphological characteristics and origins of idiopathic PVCs under a 12-lead electrocardiogram in children with structurally normal hearts. All asymptomatic monomorphic PVC patients with structurally normal hearts under 18 years of age were included in this retrospective study. Characteristics of PVCs in lead V1 under a 12-lead electrocardiogram were classified as left bundle branch block (PVC-LBBB) or right bundle branch block (PVC-RBBB). According to limb leads, PVC-LBBB or PVC-RBBB was divided into: PVCs-LBBB type I; PVCs-LBBB type II; PVCs-RBBB type I; PVCs-RBBB type II; and PVCs-RBBB type III. Out of 178 PVC patients, 94 cases of PVCs-LBBB (PVCs-LBBB type I = 60; PVCs-LBBB type II = 34) and 84 cases of PVCs-RBBB (PVCs-RBBB type I = 3; PVCs-RBBB type II = 55; PVCs-RBBB type III = 26) were identified. The frequency of PVCs-LBBB type I increased with age and the frequency of PVCs-RBBB type II and III decreased with age. Among the children monitor tested, from 1 years old to 18 years old, PVCs originating from the left or right ventricular outflow tract gradually increased with age, while PVCs originating from the branch sources decreased with age.

Chlorinated and brominated organic pollutants in shellfish from the Yellow Sea and East China Sea.

The global contamination with persistent organic pollutants (POPs), or compounds with similar characteristics, is well known. Still there are data gaps for POP concentrations from many areas in the world. The aim of the present study is to assess several legacies POPs and also hexabromocyclododecane (HBCDD) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in shellfish from three locations in the Yellow Sea and East China Sea. The sources of the contaminants are discussed. Pooled samples were treated by liquid-liquid extraction and acid and column cleanup prior to analysis by gas chromatogram equipped with electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). The by far most abundant environmental contaminant originates from dichlorodiphenyltrichloroethane (DDT), independent of species analyzed or sampling site. The results indicate ongoing or at least recent discharges of DDT. The second highest concentrations were reported for HBCDD (21-40 ng/g fat) in the shellfish, independent of sampling sites. The two natural products, 6-MeO-BDE-47 and 2'-MeO-BDE-68, were also present in the shellfish (1.3-22 and 1-14 ng/g fat, respectively). The polychlorinated biphenyl (PCB) congener CB-153 (0.8-6.5 ng/g fat), hexachlorobenzene (HCB) (1.1-3.6 ng/g fat), and ß-hexachlorocyclohexane (ß-HCH) (2.3-4.9 ng/g fat) were all higher than the concentrations of other HCH isomers, ß-endosulfan, PBDE congeners, and mirex. Apart from the DDTs and HBCDDs, it is evident that the pollution of shellfish was similar to, or lower than, the contamination of shellfish in other parts of the world.

Carvedilol has stronger anti-inflammation and anti-virus effects than metoprolol in murine model with coxsackievirus B3-induced viral myocarditis.

AIMS: This study aims to compare the effects of carvedilol and metoprolol in alleviating viral myocarditis (VMC) induced by coxsackievirus B3 (CVB3) in mice. METHODS: A total of 116 Balb/c mice were included in this study. Ninety-six mice were inoculated intraperitoneally with CVB3 to induce VMC. The CVB3 inoculated mice were evenly divided into myocarditis group (n=32), carvedilol group (n=32) and metoprolol group (n=32). Twenty mice (control group) were inoculated intraperitoneally with normal saline. Hematoxylin and eosin staining and histopathologic scoring were used to investigate the effects of carvedilol and metoprolol on myocardial histopathologic changes on days 3 and 5. In addition, serum cTn-I levels, cytokine levels and virus titers were determined using chemiluminescence immunoassay, enzyme-linked immunosorbent assay and plaque assay, respectively, on days 3 and 5. Finally, the levels of phosphorylated p38MAPK were studied using immunohistochemical staining and Western blotting on day 5. RESULTS: Carvedilol had a stronger effect than metoprolol in reducing the pathological scores of VMC induced by CVB3. Both carvedilol and metoprolol reduced the levels of cTn-I, but the effect of carvedilol was stronger. Carvedilol and metoprolol decreased the levels of myocardial pro-inflammatory cytokines and increased the expression of anti-inflammatory cytokine, with the effects of carvedilol being stronger than those of metoprolol. Carvedilol had a stronger effect in reducing myocardial virus concentration compared with metoprolol. Carvedilol was stronger than metoprolol in decreasing the levels of myocardial phosphorylated p38MAPK. CONCLUSIONS: In conclusion, carvedilol was more potent than metoprolol in ameliorating myocardial lesions in VMC, probably due to its stronger modulation of the balance between pro- and anti-inflammatory cytokines by inhibiting the activation of p38MAPK pathway through ß1- and ß2-adrenoreceptors.

[Effects of carvedilol on cardiomyocyte apoptosis in autoimmune myocarditis in mice].

OBJECTIVE: To observe the effects of carvedilol on the expression of Bcl-2, Bax and Fas in autoimmune myocarditis (AM). METHODS: A total of 60 inbred male BALB/C mice 4 - 5 weeks of age were divided at random into 3 groups as follows: AM group (n = 20), carvedilol group (n = 20) and control group (n = 20). The mice were sacrificed after gathering blood specimens by taking out the eyeballs and hearts tissue. The histological and ultrastructural changes were observed under light microscope and electron microscope. The concentrations of cardiac troponin I (cTn I) were detected by chemiluminescence immunoassay (CLIA). Immunohistochemistry (IHC) was performed to analyze the contents of Bcl-2, Bax and Fas, TUNEL to detect the apoptotic index in myocardial cells. RESULTS: There were large number of lymphocyte and monocyte infiltrates under light microscope and karyopyknosis and chromatin gathered along the nuclear membrane under electron microscope in AM group. There were no inflammations and chromatin gathering in group C. Compared with control group, the Bcl-2, Bax and Fas protein expression significantly elevated in AM group (23.48 ± 2.24 vs. 6.64 ± 1.60, 26.15 ± 2.02 vs. 5.09 ± 0.85, 21.22 ± 3.62 vs. 5.86 ± 1.37, P < 0.01). The histopathologic scores (2.60 ± 0.31 vs. 2.02 ± 0.26, P < 0.05) and karyopyknosis of carvedilol group decreased as compared with AM group. The Bcl-2, Bax and Fas protein expression (17.13 ± 1.94 vs. 23.48 ± 2.24, 17.66 ± 2.62 vs. 26.15 ± 2.02, 16.79 ± 2.83 vs. 21.22 ± 3.62, P < 0.05), AI [(16.61 ± 4.67)% vs. (24.51 ± 4.70)%, P < 0.05] and contents of cTnI [(1.878 ± 0.48) ng/ml vs. (1.102 ± 0.23) ng/ml, P < 0.05] also decreased in carvedilol group compared with AM group. CONCLUSION: Carvedilol could protect against AM by alleviating cardiomyocyte apoptosis.

[Expression of cystathionine-γ-lyase/hydrogen sulfide pathway in CVB3-induced myocarditis in mice].

OBJECTIVE: Previous studies have shown that hydrogen sulfide (H2S) plays key roles in a number of biological processes, including vasorelaxation, inflammation, apoptosis, ischemia/reperfusion and oxidative stress, which are involved in the pathogenesis of myocarditis. This study aimed to examine the expression of cystathionine-γ-lyase(CSE)/H2S pathway in mice with viral myocarditis. METHODS: Six-week-old inbred male mice were randomly assigned to control (n=25) and myocarditis group (n=30). The myocarditis and the control groups were inoculated intraperitoneally with 0.1 mL 10-5.69TCID50/mL CVB3 or vehicle (PBS) alone respectively. Ten mice were sacrificed 4 and 10 days after injection. Blood and heart specimens were harvested for measuring the content of serum H2S and the H2S production rates in cardiac tissues. Heart sections were stained with hematoxylin and eosin. Immunohistochemisty was used to detect the CSE protein expression in the heart. RESULTS: In the myocarditis group, the serum H2S content and H2S production rates in cardiac tissues were significantly higher than those in the control group 4 and 10 days after injection (P<0.05). The expression of CSE protein in the heart in the myocarditis group was also significantly higher than that in the control group (P<0.05). CONCLUSIONS: CSE and its downstream production H2S increase in mice with acute viral myocarditis. The increased expression of CSE/H2S pathway might be involved in the pathogenesis of viral myocarditis.

The dual role of the cystathionine gamma-lyase/hydrogen sulfide pathway in CVB3-induced myocarditis in mice.

The present study found that serum H2S level, H2S production rate, CSE mRNA and CSE protein levels were increased in CVB3-induced myocarditis. dl-proparglygylcine (PAG), an irreversible CSE inhibitor, decreased the infected myocardium titers on postinfection day 4, while NaHS, a H2S donor, alleviated myocardial injury and necrosis, inflammatory cell infiltration and interstitial edema on postinfection day 10. These data reveal that the CSE/H2S pathway is upregulated in the heart in a murine model of CVB3-induced myocarditis and that inhibition of endogenous H2S is beneficial to treatment early in the disease while administration of exogenous H2S is protective to infected myocardium during the later stage.