An Investigation on the Effects of Dietary Vitamin E on Juvenile Sea Urchin (Strongylocentrotus intermedius): Growth, Intestinal Microbiota, Immune Response, and Related Gene Expression.

A 90 d feeding experiment was conducted to investigate the effects of vitamin E (VE) on growth, intestinal microbiota, immune response, and related gene expression of juvenile sea urchin (Strongylocentrotus intermedius). Six dry feeds were made to contain graded levels of VE (78, 105, 152, 235, 302, and 390 mg/kg); these were named E78, E105, E152, E235, E302, and E390, respectively. Dry feed E50 and fresh kelp (HD) were used as the control diets. There were six replicates of cages in each dietary group, and each cage held 20 sea urchins with an initial body weight of approximately 1.50 g. Results exhibited that weight gain rate and gonadosomatic index (GSI) of the sea urchins were not significantly affected by dietary VE ranging from 78 to 390 mg/kg. Sea urchins in the dry feed groups showed poorer growth performance, but significantly higher GSI than those in the fresh kelp groups. The pepsin and lipase activities were not significantly promoted by low or moderate VE, but were inhibited by a high level of VE (302-390 mg/kg), while amylase and cellulase activities were significantly increased by low or moderate VE, with the highest values observed in the E105 and E235 groups, respectively. VE addition at a low dosage (105-152 mg/kg) showed inhibitory effects on immune and antioxidant enzyme activities and expression of inflammation-related genes, but showed no beneficial effects at moderate or high dosage (235-390 mg/kg), while a moderate or relatively higher level of VE (235-302 mg/kg) significantly increased the expression of several immune-related genes. The relative abundance of Proteobacteria, Actinobacteria, Ruegeria, and Maliponia in the intestine of the sea urchins increased with the increase in VE in the dry feeds. On the contrary, the relative abundance of the Firmicutes, Bacteroidetes, Escherichia-Shigella, Bacteroides, and Clostridium sensu stricto 1 gradually decreased as VE content increased. These results indicated that a moderate level of VE (172.5-262.4) can achieve ideal digestive enzyme activities and growth performance, but a relatively higher level of VE (235-302 mg/kg) was beneficial for maintaining the immune and antioxidant capacity of juvenile S. intermedius by regulating the expression of inflammation- and immune-related genes and abundance of some bacteria to a healthy state.

Effects of Supplementary Kelp Feeding on the Growth, Gonad Yield, and Nutritional and Organoleptic Quality of Subadult Sea Urchin (Strongylocentrotus intermedius) with Soya Lecithin Intake History.

A 23-week feeding experiment was conducted to investigate the effects of supplementary kelp feeding on the growth, gonad development, and nutritional and sensory properties of sea urchin (Strongylocentrotus intermedius) with soya lecithin (SL) intake history. The feeding experiment was divided into experimental phase I and phase II. During phase I, 48 subadult sea urchins (initial weight: 6.28 ± 0.07 g) were fed one of the feeds with different levels of SL (0%, 1.6%, 3.2%) or kelp (Saccharina japonica) for 12 weeks. Then, all sea urchins were fed kelp for the next 11 weeks during the phase II. Each diet was randomly allocated to six cages of sea urchins. The results of phase I showed that weight gain rate (WGR), gonadosomatic index (GSI), gonad sensory properties (color and texture), and essential amino acid (EAA) contents were not significantly affected by SL level in the feed groups. High level (3.2%) of SL suppressed gonad development of S. intermedius with retarded gametogenesis in the 3.2% SL group (stage Ⅱ) compared to those fed 0% and 1.6% SL groups (stage Ⅲ). Sea urchins fed dry feeds exhibited significantly lower WGR and values of color (redness and yellowness) and texture (hardness and gumminess) but higher contents of EAA in the gonads than those fed kelp. The n-3/n-6 polyunsaturated fatty acid (PUFA) and eicosapentaenoic acid (EPA) of gonads in the groups fed with dry feeds showed no significant differences, but were significantly lower than that of kelp group. At the end of phase II, the gonad yellowness and EPA content of gonads in all dry feed groups were significantly increased by supplementary kelp feeding, with a higher increase observed in S. intermedius with SL intake history, while arachidonic acid (ARA) content was significantly improved by supplementary kelp feeding in S. intermedius with SL intake history. Gonad texture was improved to some extent by supplementary kelp feeding. These results indicated that S. intermedius fed dry feeds showed significantly higher GSI and EAA but poorer organoleptic quality and lower n-3/n-6 PUFA and EPA than those fed kelp. Kelp supplementary feeding improved the fatty acid value and organoleptic quality of gonads, especially for the sea urchins with SL intake history.

Identification of the Best Anthropometric Index for Predicting the 10-Year Cardiovascular Disease in Southwest China: A Large Single-Center, Cross-Sectional Study.

INTRODUCTION: This population-based cross-sectional study aimed to identify the best predictor of the 10-year cardiovascular (CV) high risk among old and new anthropometric indices. METHODS: We investigated 76,915 adults older than 18 years of age living in southwest China. Ten obesity indices were calculated. The 10-year cardiovascular disease (CVD) risk was estimated using the Framingham risk score. Receiver operating characteristic curve analysis was performed to assess the ability of the anthropometric index to predict the 10-year high risk of CVD events. RESULTS: The waist-to-hip ratio (WHR) had the highest area under the curve (AUC) value (0.711; sensitivity: 62.22%, specificity: 42.73%) in men, while the body fat index (BAI) had the lowest AUC value (0.624, sensitivity: 49.07%, specificity: 54.84%). The waist-to-height ratio (WHtR) and the body roundness index (BRI) showed the highest AUC value (0.751, sensitivity: 39.24%, 39.83%, specificity: 75.68%, 68.59%) in women, while the BAI showed the lowest AUC value (0.671, sensitivity: 53.15%, specificity: 57.14%). CONCLUSIONS: The WHR was the best anthropometric measure for assessing the 10-year high risk of CVD in men, while the WHtR and BRI were the best measures for women. In men, the WHR should be < 0.88, and in women, the WHtR should be < 0.502 or the BRI should be < 3.41.

Clinical significance of the serum IgM and IgG to SARS-CoV-2 in coronavirus disease-2019.

OBJECTIVE: To explore the clinical value of serum IgM and IgG to SARS-CoV-2 in COVID-19. METHODS: 105 COVID-19 patients were enrolled as the disease group. 197 non-COVID-19 patients served as the control group. Magnetic chemiluminescent immunoassay (MCLIA) was used to detect the IgM and IgG. RESULTS: The peak of positive rates of SARS-CoV-2 IgM was about 1 week earlier than that of IgG. It reached to peak within 15-21 days and then began a slowly decline. The positive rates of IgG were increased with the disease course and reached the peak between 22 and 39 days. The differences in sensitivity of the three detection modes (IgM, IgG, and IgM + IgG) were statistically significant. The largest group of test cases (illness onset 15-21 days) showed that the positive rate of IgG was higher than IgM. Also, the sensitivity of IgM combined with IgG was higher than IgM or IgG. IgM and IgG were monitored dynamically for 16 patients with COVID-19, the results showed that serological transformation of IgM was carried out simultaneously with IgG in seven patients, which was earlier than IgG in four patients and later than IgG in five patients. CONCLUSION: The detection of SARS-CoV-2 IgM and IgG is very important to determine the course of COVID-19. Nucleic acid detection combined with serum antibody of SARS-CoV-2 may be the best laboratory indicator for the diagnosis of SARS-CoV-2 infection and the phrase and predication for prognosis of COVID-19.

Electrochemical competitive immunodetection of messenger RNA modified with N6-methyladenosine by using DNA-modified mesoporous PtCo nanospheres.

N6-Methyladenosine (m6A) is the most abundant RNA modification in eukaryotic messenger RNA (mRNA). A highly sensitive electrochemical immunosensor is described for the determination of m6A-RNA. The method is based on the use of antibody (anti-m6A) and PtCo mesoporous nanospheres (MPNs). The analogously modified probe of type m6A-DNA-PtCo competes with m6A-RNA for antibodies on the gold electrode as an electrical signal probe. The electrical signal, best acquired at a working potential of -0.37 V (vs. Ag/AgCl) reflects the concentration of m6A. The PtCo MPNs catalyze the reduction of H2O2, and this amplifies the current and enhances sensitivity. The detection time of the assay is <1.5 h. Under optimal conditions, response is linear in the 0.005 to 100 nM m6A RNA concentration range, and the detection limit is 2.1 pM. The results obtained by this immunoassay with human cell lines are comparable to those obtained with a commercial kit. Graphical abstractSchematic representation of a method for electrochemical determination of m6A-modified mRNA. Anti-m6A Ab: antibody against m6A; BSA: bovine serum albumin; PtCo: PtCo mesoporous nanospheres; SH-m6A-DNA: DNA modified with both m6A and thiol groups; DPV: differential pulse voltammetry.

A novel enzyme-free electrochemical biosensor for rapid detection of Pseudomonas aeruginosa based on high catalytic Cu-ZrMOF and conductive Super P.

Pseudomonas aeruginosa (P. aeruginosa) is one of the most intractable multidrug-resistant bacteria of nosocomial infections. The conventional detection methods for P. aeruginosa are time-consuming or low detection sensitivity. Here, a novel enzyme-free electrochemical biosensor was constructed to detect P. aeruginosa rapidly and sensitively. Firstly, the ZrMOF with large surface area was synthesized, which offers excellent adsorption. Further, it was connected with a specific amount of Cu2+ to synthesize Cu-ZrMOF with high catalytic activity. Then the Cu-ZrMOF@Aptamer@DNA nanocomposite was composed and served as the signal probe to catalyse the decomposition of H2O2. Moreover, high conductive Super P was introduced to increase the electron transfer for satisfactory detection sensitivity. The proposed biosensor was constructed and used to quantify P. aeruginosa with a wide linearity range of 10-106 CFU mL-1 and a low limit of detection of 2 CFU mL-1 (S/N = 3). Compared with conventional methods, the new method of present biosensor is more sensitive, and less time-consuming (only within 120 min). The analytical performance evaluation indicated that the biosensor exhibits good reproducibility and specificity. Finally, the biosensor was successfully applied to quantify P. aeruginosa in spiked urine samples. These results show that the proposed electrochemical biosensor might be a potential laboratory tool for detecting P. aeruginosa in the clinic.

Voltammetric immunoassay for Mycobacterium tuberculosis secretory protein MPT64 based on a synergistic amplification strategy using rolling circle amplification and a gold electrode modified with graphene oxide, Fe3O4 and Pt nanoparticles.

The authors describe an electrochemical immunoassay for ultrasensitive determination of the Mycobacterium tuberculosis (MTb) secretory protein MPT64 which is an antigen for early diagnosis of infection with MTb. Protein G was used to immobilize antibodies against MPT64 on a gold electrode. Graphene oxide with its large surface area was used as a carrier to anchor magnetite (Fe3O4) and platinum (Pt) nanoparticles. The nanocomposite of type GO@Fe3O4@Pt was used as a signal reporter with excellent catalytic activity and recyclability. The nanocomposite exhibits peroxidase-like activity for hydrogen peroxide, best at -0.25 V (vs. Ag/AgCl). It works over a wide range of pH values (2-10) and temperatures (25-65 °C). Further signal amplification strategy was accomplished by rolling circle amplification. This voltammetric assay has a linear response to the logarithm of MPT64 concentration in the range from 5.0 fg·mL-1 to 1.0 ng·mL-1 and a detection limit of 0.34 fg·mL-1 (at a signal to noise ratio of 3, for n = 10). The assay can be completed within 4 h. It was successfully applied to the determination of MPT64 in spiked serum samples. Conceivably, the assay has a large potential in providing laboratory evidence for rapid diagnosis of MTb infection. Graphical abstract An electrochemical biosensor was developed for rapid detection of Mycobacterium tuberculosis secretory protein MPT64. The detection signal was synergistically amplified by GO@Fe3O4@Pt and rolling circle amplification. Phi29: phi29 DNA polymerase; BSA: bovine serum albumin; GO: graphene oxide.