Molecular cytogenetic analyses of Epinephelus bruneus and Epinephelus moara (Perciformes, Epinephelidae)

Genus Epinephelus (Perciformes, Epinephelidae), commonly known as groupers, are usually difficult in species identification for the lack and/or change of morphological specialization. In this study, molecular cytogenetic analyses were firstly performed to identify the closely related species Epinephelus bruneus and E. moara in this genus. The species-specific differences of both fish species showed in karyotype, chromosomal distribution of nucleolar organizer regions (NORs) and localization of 18S rDNA. The heterochromatin (interstitial C-bands) and distribution pattern of telomere (TTAGGG)n in E. bruneus revealed the chromosomal rearrangements and different karyotypic evolutionary characteristics compared to those in E. moara. The cytogenetic data suggested that the lineages of E. bruneus and E. moara were recently derived within the genus Epinephelus, and E. moara exhibited more plesiomorphic features than E. bruneus. All results confirmed that E. moara, which has long been considered a synonym of E. bruneus, is a distinct species in the family Epinephelidae. In addition, molecular cytogenetic analyses are useful in species differentiation and phylogenetic reconstruction in groupers

Near infrared spectroscopy coupled with radial basis function neural network for at-line monitoring of Lactococcus lactis subsp. fermentation

AbstractIn our previous work, partial least squares (PLSs) were employed to develop the near infrared spectroscopy (NIRs) models for at-line (fast off-line) monitoring key parameters of Lactococcus lactis subsp. fermentation. In this study, radial basis function neural network (RBFNN) as a non-linear modeling method was investigated to develop NIRs models instead of PLS. A method named moving window radial basis function neural network (MWRBFNN) was applied to select the characteristic wavelength variables by using the degree approximation (Da) as criterion. Next, the RBFNN models with selected wavelength variables were optimized by selecting a suitable constant spread. Finally, the effective spectra pretreatment methods were selected by comparing the robustness of the optimum RBFNN models developed with pretreated spectra. The results demonstrated that the robustness of the optimal RBFNN models were better than the PLS models for at-line monitoring of glucose and pH of L. lactis subsp. fermentation

Screening and Characterization of Potential Antioxidant Probiotics Isolated from the Gut of Hybrid Grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂)

Some symbiotic probiotics have antioxidant activities and could improve the antioxidant capacity of the host. There is still no report on the screening of host-derived antioxidant probiotics for grouper farming. In this study, 369 out of 583 isolates were screened from the gut of hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus♂) based on their non-hemolytic characteristics. Subsequent preliminary screening with 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) scavenging rate assay resulted in 36 potential antioxidant isolates. After comprehensive evaluation with nine different antioxidant assays (DPPH scavenging rate, 2,2’-azino-bis (3-ethylbezothiazoline)-6-sulfonic acid radical scavenging rate, iron ion reducing ability, reducing activity, O2-· scavenging rate,·OH scavenging rate, ferrous ion chelating rate, hydrogen peroxide tolerance, oxygen-free radical scavenging ability, et al.), 10 isolates with strong antioxidant abilities were screened from 36 potential antioxidant isolates. Then some other probiotic properties, such as simulated gastrointestinal fluid tolerance, adhesion, digestive enzyme activity, and antibacterial activity of the 10 selected isolates were evaluated. All 10 isolates were also identified using the molecular method. Finally, Vibrio rhodolitus GO 91 and Shewanella corallii GO 310, as representatives of the two genera resulting from the identification of the 10 isolates, and with the best overall probiotic properties, were selected from the 10 isolates. Isolates GO 91 and GO 310 were further tested for their safety performances. Antibiotic sensitivity tests showed that GO91 and GO310 were sensitive to many commonly used aquaculture antibiotics. The in vivo challenge test of GO 91 and GO 310 didn’t cause any disease symptoms or death in hybrid grouper. Therefore, isolates GO 91 and GO 310 showed great potential to be used as probiotics in hybrid grouper farming

Wireless Power Transfer for Implanted Medical Application: A Review

With ever-increasing concerns on health and environmental safety, there is a fast-growing interest in new technologies for medical devices and applications. Particularly, wireless power transfer (WPT) technology provides reliable and convenient power charging for implant medical devices without additional surgery. For those WPT medical systems, the width of the human body restricts the charging distance, while the specific absorption rate (SAR) standard limits the intensity of the electromagnetic field. In order to develop a high-efficient charging strategy for medical implants, the key factors of transmission distance, coil structure, resonant frequency, etc. are paid special attention. In this paper, a comprehensive overview of near-field WPT technologies in medical devices is presented and discussed. Also, future development is discussed for the prediction of different devices when embedded in various locations of the human body. Moreover, the key issues including power transfer efficiency and output power are addressed and analyzed. All concerning characteristics of WPT links for medical usage are elaborated and discussed. Thus, this review provides an in-depth investigation and the whole map for WPT technologies applied in medical applications

Variable Time-Step Physics Engine with Continuous Compliance Contact Model for Optimal Robotic Grinding Trajectory Planning

In the transition from virtual environments to real-world applications, the role of physics engines is crucial for accurately emulating and representing systems. To address the prevalent issue of inaccurate simulations, this paper introduces a novel physics engine uniquely designed with a compliant contact model designed for robotic grinding. It features continuous and variable time-step simulations, emphasizing accurate contact force calculations during object collision. Firstly, the engine derives dynamic equations considering spring stiffness, damping coefficients, coefficients of restitution, and external forces. This facilitates the effective determination of dynamic parameters such as contact force, acceleration, velocity, and position throughout penetration processes continuously. Secondly, the approach utilizes effective inertia in developing the contact model, which is designed for multi-jointed robots through pose transformation. The proposed physics engine effectively captures energy conversion in scenarios with convex contact surface shapes through the application of spring dampers during collisions. Finally, the reliability of the contact solver in the simulation was verified through bouncing ball experiments and robotic grinding experiments under different coefficients of restitution. These experiments effectively recorded the continuous variations in parameters, such as contact force, verifying the integral stability of the system. In summary, this article advances physics engine technology beyond current geometrically constrained contact solutions, enhancing the accuracy of simulations and modeling in virtual environments. This is particularly significant in scenarios wherein there are constant changes in the outside world, such as robotic grinding tasks

Complete genome sequence and comparative genomics of the golden pompano (Trachinotus ovatus) pathogen, Vibrio harveyi strain QT520

Vibrio harveyi is a Gram-negative, halophilic bacterium that is an opportunistic pathogen of commercially farmed marine vertebrate species. To understand the pathogenicity of this species, the genome of V. harveyi QT520 was analyzed and compared to that of other strains. The results showed the genome of QT520 has two unique circular chromosomes and three endogenous plasmids, totaling 6,070,846 bp with a 45% GC content, 5,701 predicted ORFs, 134 tRNAs and 37 rRNAs. Common virulence factors, including ACF, IlpA, OmpU, Flagellin, Cya, Hemolysin and MARTX, were detected in the genome, which are likely responsible for the virulence of QT520. The results of genomes comparisons with strains ATCC 33843 (392 (MAV)) and ATCC 43516 showed that greater numbers genes associated with types I, II, III, IV and VI secretion systems were detected in QT520 than in other strains, suggesting that QT520 is a highly virulent strain. In addition, three plasmids were only observed in the complete genome sequence of strain QT520. In plasmid p1 of QT520, specific virulence factors (cyaB, hlyB and rtxA) were identified, suggesting that the pathogenicity of this strain is plasmid-associated. Phylogenetic analysis of 12 complete Vibrio sp. genomes using ANI values, core genes and MLST revealed that QT520 was most closely related to ATCC 33843 (392 (MAV)) and ATCC 43516, suggesting that QT520 belongs to the species V. harveyi. This report is the first to describe the complete genome sequence of a V. harveyi strain isolated from an outbreak in a fish species in China. In addition, to the best of our knowledge, this report is the first to compare the V. harveyi genomes of several strains. The results of this study will expand our understanding of the genome, genetic characteristics, and virulence factors of V. harveyi, setting the stage for studies of pathogenesis, diagnostics, and disease prevention

Case of <i>Vibrio vulnificus</i> Infection in <i>Orechromis niloticus</i> during Suspension of Recirculating Aquaculture System

During a suspension of a GIFT tilapia broodstock recirculating aquaculture system (RAS), a significant fish mortality event occurred. To determine the cause, four bacterial strains were isolated from affected fish and identified as Vibrio vulnificus through 16S rDNA sequencing. Virulence assays confirmed the pathogenicity of these strains, with the most virulent, CS-4, selected for a further analysis. Antimicrobial testing revealed CS-4’s sensitivity to 19 antibiotics, including meloxicillin and Gentamicin. Challenge tests indicated varied 7-day Lethal Dose 50 (LD50) values for CS-4 depending on the infection route, with immersion after skin injury being the most lethal. Additionally, the effects of salinity, crowding with air exposure, and nitrite on tilapia mortality were evaluated. The results showed that salinity stress increased the mortality rate of tilapia infected with V. vulnificus through immersion, and that salinity stress and V. vulnificus infection had a synergistic effect. A 20 min crowding with air exposure stress reduced the mortality rate of Nile tilapia infected with V. vulnificus. Nitrite stress had little effect on the mortality rate of tilapia infected with V. vulnificus. The results of the risk factor analysis indicated that salinity was the main factor affecting tilapia mortality caused by V. vulnificus infection. This study will serve as a valuable reference for the future management of similar RAS

The effect of Trifluridine/tipiracil for patients with heavily pretreated metastatic gastric cancer: A protocol for systematic review and meta-analysis

Purpose. The presentation of this protocol is to scientifically evaluate the efficacy and safety of Trifluridine/tipiracil in patients with highly pretreated metastatic gastric cancer. Methods. The protocol followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. We will systematically search MEDLINE/PubMed, Embase, Cochrane Library, CNKI (China national knowledge internet) databases up to 1 July 2020 to identify published articles. Using the Cochrane risk assessment tool to assess the methodological quality of the RCTs, and all included studies will be analyzed according to the criteria in the Cochrane Handbook. Review Manager 5.3 software will be used for literature quality evaluation and data analysis. Results. Objective to evaluate the efficacy and safety of Trifluridine/tipiracil in patients with heavily pretreated metastatic gastric cancer by analyzing the eligible data extracted under limited conditions. Conclusion. This study provides clear evidence to evaluate the effectiveness and safety of Trifluridine/tipiracil for patients with highly pretreated metastatic gastric cancer, and the findings will also be published in a peer-reviewed journals

First characterization of bacterial pathogen, Vibrio alginolyticus, for Porites andrewsi White syndrome in the South China Sea.

White syndrome, a term for scleractinian coral disease with progressive tissue loss, is known to cause depressed growth and increased morality of coral reefs in the major oceans around the world, and the occurrence of this disease has been frequently reported in the past few decades. Investigations during April to September in both 2010 and 2011 identified widespread Porites andrewsi White syndrome (PAWS) in Xisha Archipelago, South China Sea. However, the causes and etiology of PAWS have been unknown.A transmission experiment was performed on P. andrewsi in the Qilianyu Subgroup (QLY). The results showed that there was a significant (P ≤ 0.05) difference between test and control groups after 28 days if the invalid replicates were excluded. Rates of tissue loss ranged from 0.90-10.76 cm(2) d(-1) with a mean of 5.40 ± 3.34 cm(2) d(-1) (mean ± SD). Bacterial strains were isolated from the PAWS corals at the disease outbreak sites in QLY of the Xisha Archipelago, South China Sea, and included in laboratory-based infection trials to satisfy Koch's postulates for establishing causality. Following exposure to bacterial concentrations of 10(5) cells mL(-1), the infected colonies exhibited similar signs to those observed in the field. Using phylogenetic 16S rRNA gene analysis, classical phenotypic trait comparison, Biolog automatic identification system, MALDI-TOF mass spectrometry and MALDI Biotyper method, two pathogenic strains were identified as Vibrio alginolyticus .This is the first report of V. alginolyticus as a pathogenic agent of PAWS in the South China Sea. Our results point out an urgent need to develop sensitive detection methods for V. alginolyticus virulence strains and robust diagnostics for coral disease caused by this and Vibrio pathogenic bacterium in the South China Sea

Lithium and Copper Induce the Osteogenesis-Angiogenesis Coupling of Bone Marrow Mesenchymal Stem Cells via Crosstalk between Canonical Wnt and HIF-1α Signaling Pathways

The combination of osteogenesis and angiogenesis dual-delivery trace element-carrying bioactive scaffolds and stem cells is a promising method for bone regeneration and repair. Canonical Wnt and HIF-1α signaling pathways are vital for BMSCs’ osteogenic differentiation and secretion of osteogenic factors, respectively. Simultaneously, lithium (Li) and copper (Cu) can activate the canonical Wnt and HIF-1α signaling pathway, respectively. Moreover, emerging evidence has shown that the canonical Wnt and HIF signaling pathways are related to coupling osteogenesis and angiogenesis. However, it is still unclear whether the lithium- and copper-doped bioactive scaffold can induce the coupling of the osteogenesis and angiogenesis in BMSCs and the underlying mechanism. So, we fabricated a lithium- (Li+-) and copper- (Cu2+-) doped organic/inorganic (Li 2.5-Cu 1.0-HA/Col) scaffold to evaluate the coupling osteogenesis and angiogenesis effects of lithium and copper on BMSCs and further explore its mechanism. We investigated that the sustained release of lithium and copper from the Li 2.5-Cu 1.0-HA/Col scaffold could couple the osteogenesis- and angiogenesis-related factor secretion in BMSCs seeding on it. Moreover, our results showed that 500 μM Li+ could activate the canonical Wnt signaling pathway and rescue the XAV-939 inhibition on it. In addition, we demonstrated that the 25 μM Cu2+ was similar to 1% oxygen environment in terms of the effectiveness of activating the HIF-1α signaling pathway. More importantly, the combination stimuli of Li+ and Cu2+ could couple the osteogenesis and angiogenesis process and further upregulate the osteogenesis- and angiogenesis-related gene expression via crosstalk between the canonical Wnt and HIF-1α signaling pathway. In conclusion, this study revealed that lithium and copper could crosstalk between the canonical Wnt and HIF-1α signaling pathways to couple the osteogenesis and angiogenesis in BMSCs when they are sustainably released from the Li-Cu-HA/Col scaffold