Effect of cadmium in the gonads of mussel (Mytilus coruscus): an ionomics and proteomics study.

The mussel Mytilus coruscus is an important and very popular seafood in China and widespread along the eastern coast of China. In this study, we investigated the molecular response of mussel gonads to cadmium accumulation at two concentrations (80 and 200 µg/L) for 30 days using ionomics and proteomics techniques. The shrinkage of the cells and moderate hemocytic infiltration were observed in the Cd-treated groups. The strontium, selenium (Se), and zinc contents were significantly altered, and the relationships between iron, copper, Se, manganese, calcium, sodium, and magnesium were also significantly altered. Label-free quantitative proteomics analysis revealed a total of 227 differentially expressed proteins. These proteins were associated with multiple biological processes, including the tricarboxylic acid cycle, structural reorganization of cells, biosynthesis of amino acids, inflammatory response of cells, and tumorigenesis. Nonetheless, our ionomics and proteomics analysis revealed that mussels could partly alleviate the adverse effects of Cd by altering the metal contents and correlations between minerals, thereby enhancing the biosynthesis of some amino acids and activity of antioxidant enzymes. Overall, this study provides an insight into the mechanism underlying Cd toxicity in mussel gonads from a metal and protein perspective.

Prediction of Surgical Approach in Mitral Valve Disease by XGBoost Algorithm Based on Echocardiographic Features.

In this study, we aimed to develop a prediction model to assist surgeons in choosing an appropriate surgical approach for mitral valve disease patients. We retrospectively analyzed a total of 143 patients who underwent surgery for mitral valve disease. The XGBoost algorithm was used to establish a predictive model to decide a surgical approach (mitral valve repair or replacement) based on the echocardiographic features of the mitral valve apparatus, such as leaflets, the annulus, and sub-valvular structures. The results showed that the accuracy of the predictive model was 81.09% in predicting the appropriate surgical approach based on the patient's preoperative echocardiography. The result of the predictive model was superior to the traditional complexity score (81.09% vs. 75%). Additionally, the predictive model showed that the three main factors affecting the choice of surgical approach were leaflet restriction, calcification of the leaflet, and perforation or cleft of the leaflet. We developed a novel predictive model using the XGBoost algorithm based on echocardiographic features to assist surgeons in choosing an appropriate surgical approach for patients with mitral valve disease.

Structural Characterization and In Vitro Antioxidant Activity of Metallothionein from Oratosquilla oratoria.

We report here the purification of a novel metal-binding protein from Oratosquilla oratoria (O. oratoria MT-1) by gel and ion-exchange chromatography. SDS-PAGE and MALDI-TOF analyses demonstrated that isolated O. oratoria MT-1 was of high purity with a molecular weight of 12.4 kDa. The fluorescence response to SBD-F derivatives revealed that O. oratoria MT-1 contained a large number of sulfhydryl groups, which is a general property of metallothioneins. Zn and Cu metal stoichiometries for O. oratoria MT-1 were 3.97:1 and 0.55:1, respectively. The proportion of cysteine (Cys) residues in the amino acid composition was 32.69%, and aromatic amino acids were absent. The peptide sequence coverage with Macrobrachium rosenbergii calmodulin (accession AOA3S8FSK5) was 60%. Infrared spectroscopy of O. oratoria MT-1 revealed two obvious peaks at absorption frequencies for the amide I band and the amide II band. CD spectra revealed that the secondary structure was mainly composed of random coil (57.6%) and ß-sheet (39.9%). An evaluation of in vitro antioxidant activity revealed that isolated O. oratoria MT-1 has strong reducing activities, exhibiting scavenging rates for DPPH and OH of 77.8% and 75.8%, respectively (IC50 values 0.57 mg/mL and 1.1 mg/mL). O. oratoria MT-1 may be used as a functional additive in cosmetics, health foods, and medical products, as well as a reference material for quantitative analysis of metallothionein in such products.

Metals in Ten Commercial Demersal Fish from the East China Sea: Contribution to Aquatic Products Nutrition and Toxic Risk Assessment.

Metal accumulation in the marine environment can increase the metal content of fish living in it. For this reason, it is essential to evaluate the nutrition from fish consumption and assess metal toxicity risk. Ten species of demersal fish, which are part of the daily diet of coastal residents, were sampled using trammel net in the East China Sea. Levels of the microelements, the constant elements, and the toxic elements of muscle tissue were analyzed. Spiny red gurnard had the highest concentrations of calcium, copper, and iron, whereas pufferfish and threadfin porgy were good sources of zinc and magnesium. The levels of lead, cadmium, and inorganic arsenic in all samples were below the limit values according to Chinese national standards. Although some concerns were raised about the concentration of mercury (Hg) in threadfin porgy, silver croaker, and fivespot flounder, molar ratios (selenium, Se:Hg) and the Se health benefit values (HBVSe) indicated that they were safe for human consumption. Additionally, the estimated weekly intake and % weekly contribution of 10 fish species with different elements were provided, giving a reference for the people's healthy consumption.

Purification and structure analysis of zinc-binding protein from Mizuhopecten yessoensis.

Zn-binding protein was obtained after purification from scallops (Mizuhopecten yessoensis) using gel permeation and ion-exchange chromatography. Amino acid determination showed that the cysteine of the zinc-binding protein accounted for one-third of the total amino acids, which is a typical feature of metallothionein (MT). The spectra of Fourier Transform Infrared Spectroscopy (FTIR) and Circular Dichroism (CD) were analyzed to predict the secondary structure information of zinc-binding protein: the α-helix was 46.55%, the ß-sheets was 27.07%, the random coil was 16.48%, and the ß-turns was 9.89%. Using a commercial kit to measure its antioxidant activity in vitro, the result showed that it had good scavenging ability to 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (·OH), and reducing the ability to ferrous iron ions. With the process provided by this study, zinc-binding protein can be prepared in large quantities, which is the basis for its future commercialization. PRACTICAL APPLICATIONS: According to the extraction and purification process established in this study, a large amount of zinc-bound MT from the viscera of scallops can be obtained. And the zinc-bound MT had good antioxidant activity. In addition, the yield of each purification step has been calculated. The zinc-bound MTs from scallop' viscera can be prepared in large quantities by directly using the process in this manuscript or by equal magnification of this process. In the future, large-scale production can be considered to increase the economic value of scallops' viscera.

Purification, secondary structure and antioxidant activity of metallothionein zinc-binding proteins from Arca subcrenata.

Zinc-binding proteins named MT-M-I and MT-M-II were obtained after purification from metal-exposed hairy clams (Arca subcrenata) using gel permeation and ion-exchange chromatography. MT-M-I and MT-M-II were resolved by ion-exchange chromatography, and they were found to have similar molecular weights. MT-M-I and MT-M-II can bind 6 and 7 equivalents of Zn2+ in vitro, and they showed unusual migration behaviors in Tricine sodium dodecyl sulfate polyacrylamide gel electrophoresis (Tricine-SDS-PAGE). Such migration behaviors may be due to themetal thiolate clusters in these proteins. In terms of amino acid composition, the proportion of cysteine in MT-M-I and MT-M-II was approximately 30%, and glycine accounted for approximately 15%, where as aromatic amino acids were absent. Considering the performance in Tricine-SDS-PAGE and the amino acid compositions, MT-M-I and MT-M-II conform to the molecular characteristics of the metallothionein proteins. The structures were explored using circular dichroism (CD) and Fourier-transform infrared spectroscopy (FTIR). Also determined the antioxidant activities in terms of DPPH radical scavenging ability, hydroxyl radical (·OH) scavenging ability, and ferric-reducing/antioxidant power. The antioxidant activities of MT-M-I were found to be stronger than those of MT-M-II.

miR-183 and miR-141 in lesion tissues are potential risk factors for poor prognosis in patients with infected abdominal aortic aneurysm.

The expression levels of micro ribonucleic acid-183 (miR-183) and miR-141 in the lesion tissues of infected abdominal aortic aneurysm (IAAA) and their relationship with prognosis were investigated. Thirty-six patients with IAAA admitted and who underwent vascular surgery in People's Hospital of Shenzhen from June 2003 to June 2013 were selected. Reverse transcription polymerase chain reaction (RT-PCR) was utilized to detect the expression levels of miR-183 and miR-141 in lesion tissues and adjacent tissues 1 cm away from the aneurysm in 36 patients with IAAA. The relationship between the expression levels of miR-183 and miR-141 as well as the clinicopathological features of patients with IAAA were analyzed, and the factors influencing the prognosis of IAAA were analyzed by univariate and multiva-riate analysis. The expression levels of miR-183 and miR-141 were significantly downregulated in the lesions of patients with IAAA, and miR-183 and miR-141 levels in the lesion tissues of the IAAA patients were significantly lower than those in the adjacent tissues (P<0.05). The expression levels of miR-183 and miR-141 were not related to sex, age, history of hypertension, and alcoholism (P>0.05), but they were related to smoking history or aneurysm size (P<0.05). The overall survival rate of patients with IAAA was 41.6% (15/36). The multivariate analysis found that aneurysm size, low expression of miR-183, and low expression of miR-141 were independent factors affecting the prognosis of patients with IAAA. In conclusion, the expression levels of miR-183 and miR-141 in the lesion tissues of IAAA are low, and the lower the expression level is, the worse the prognosis gets. miR-183 and miR-141 can be used as predictors of prognosis in patients with IAAA.

Preventive effect of hesperidin modulates inflammatory responses and antioxidant status following acute myocardial infarction through the expression of PPAR­Î³ and Bcl­2 in model mice.

Hesperetin is the main pharmacological ingredient of fruit of the citrus family, rutaceae. It is a flavanone, which has potent antioxidation and anti­inflammatory activities. The present study investigated the preventive effect of hesperidin in the modulation of acute myocardial infarction (AMI)­induced inflammatory responses and antioxidant status in a mouse model. The levels of creatine kinase­MB, tumor necrosis factor (TNF­α), interleukin (IL)­1ß, IL­6, monocyte chemoattractant protein 1 (MCP­1), intercellular adhesion molecule 1 (ICAM­1), malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and caspase­3/9 were measured using ELISA kits. Western blot analysis analyzed p53 and B­cell lymphoma 2 (Bcl­2)­associated X protein/Bcl­2, and induced the expression of peroxisome proliferator­activated receptor­Î³ (PPAR­Î³). Hesperidin markedly decreased the myocardial infarction area, heart weight/body weight ratio and activity of creatine kinase­MB in AMI mice. Hesperidin treatment caused a significant decrease in the levels of TNF­α, IL­1ß, IL­6, MCP­1, ICAM­1, MDA, CAT, SOD and caspase­3/9 in mice with AMI. Hesperidin also significantly suppressed the protein expression levels of p53 and Bax/Bcl­2, and induced the expression of peroxisome proliferator­activated receptor­Î³ (PPAR­Î³) in mice with AMI. The preventive effect of hesperidin modulated the inflammatory response and antioxidant status following AMI through downregulation of the expression of PPAR­Î³ and Bcl­2 in the model mice.

Hibiscus chlorotic ringspot virus coat protein inhibits trans-acting small interfering RNA biogenesis in Arabidopsis.

Many plant and animal viruses have evolved suppressor proteins to block host RNA silencing at various stages of the RNA silencing pathways. Hibiscus chlorotic ringspot virus (HCRSV) coat protein (CP) is capable of suppressing the transiently expressed sense-RNA-induced post-transcriptional gene silencing (PTGS) in Nicotiana benthamiana. Here, constitutively expressed HCRSV CP from transgenic Arabidopsis was found to be able to rescue expression of the silenced GUS transgene. The HCRSV CP-transgenic Arabidopsis (line CP6) displayed several developmental abnormalities: elongated, downward curled leaves and a lack of coordination between stamen and carpel, resulting in reduced seed set. These abnormalities are similar to those observed in mutations of the genes of Arabidopsis RNA-dependent polymerase 6 (rdr6), suppressor of gene silencing 3 (sgs3), ZIPPY (zip) and dicer-like 4 (dcl4). The accumulation of microRNA (miRNA) miR173 remained stable; however, the downstream trans-acting small interfering RNA (ta-siRNA) siR255 was greatly reduced. Real-time PCR analysis showed that expression of the ta-siRNA-targeted At4g29770, At5g18040, PPR and ARF3 genes increased significantly, especially in the inflorescences. Genetic crossing of CP6 with an amplicon-silenced line (containing a potato virus X-green fluorescent protein transgene under the control of the 35S cauliflower mosaic virus promoter) suggested that HCRSV CP probably interfered with gene silencing at a step after RDR6. The reduced accumulation of ta-siRNA might result from the interference of HCRSV CP with Dicer-like protein(s), responsible for the generation of dsRNA in ta-siRNA biogenesis.

Host-induced avirulence of hibiscus chlorotic ringspot virus mutants correlates with reduced gene-silencing suppression activity.

Post-transcriptional gene silencing (PTGS) and virus-encoded gene-silencing suppressors are defence and counterdefence strategies developed by host and pathogens during evolution. Using a green fluorescence protein-based transient suppression system, the coat protein (CP) of Hibiscus chlorotic ringspot virus (HCRSV) was identified as a strong gene-silencing suppressor. CP suppressed sense RNA-induced but not dsRNA-induced local and systemic PTGS. This is different from another virus in the genus Carmovirus, Turnip crinkle virus (TCV), the CP of which strongly suppresses dsRNA-induced PTGS. HCRSV CP domain deletion mutants lost their suppression function, indicating that the complete CP is essential for suppression of PTGS. When CP was expressed from a Potato virus X (PVX) vector, it was able to enhance the symptom severity and to increase the accumulation of PVX RNA. Here, it is proposed that HCRSV CP suppresses PTGS at the initiation step, which is different from TCV CP. In addition, a previous study demonstrated that CP mutants resulting from serial passage of HCRSV in its local lesion host also showed a significantly reduced suppression function, indicating that host-induced mutations that lead to avirulence of HCRSV in kenaf correlate with its reduced ability to suppress PTGS.