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801.
802.
Shuilin Cai Nan Pan Min Xu Yongchang Su Kun Qiao Bei Chen Bingde Zheng Meitian Xiao Zhiyu Liu 《Marine drugs》2021,19(12)
Angiotensin-I-converting enzyme (ACE) is a crucial enzyme or receptor that catalyzes the generation of potent vasopressor angiotensin II (Ang II). ACE inhibitory peptides from fish showed effective ACE inhibitory activity. In this study, we reported an ACE inhibitory peptide from Takifugu bimaculatus (T. bimaculatus), which was obtained by molecular docking with acid-soluble collagen (ASC) hydrolysate of T. bimaculatus. The antihypertensive effects and potential mechanism were conducted using Ang-II-induced human umbilical vein endothelial cells (HUVECs) as a model. The results showed that FNLRMQ alleviated the viability and facilitated apoptosis of Ang-II-induced HUVECs. Further research suggested that FNLRMQ may protect Ang-II-induced endothelial injury by regulating Nrf2/HO-1 and PI3K/Akt/eNOS signaling pathways. This study, herein, reveals that collagen peptide FNLRMQ could be used as a potential candidate compound for antihypertensive treatment, and could provide scientific evidence for the high-value utilization of marine resources including T. bimaculatus. 相似文献
803.
804.
T‐C Cheng Y‐S Lai I‐Y Lin C‐P Wu S‐L Chang T‐I Chen M‐S Su 《Journal of fish diseases》2010,33(2):161-169
Establishment and characterization of two cobia, Rachycentron canadum, cell lines derived from cobia brain (CB) and cobia fin (CF) are described. Caudal fin and brain from juvenile cobia were dissociated for 30 and 10 min, respectively, in phosphate‐buffered saline containing 0.25% trypsin at 25 °C. The optimal culture condition for both dissociated cells (primary cell culture) was at 28 °C in Leibovitz‐15 medium containing 10% foetal bovine serum. The cells have been sub‐cultured at a ratio of 1:2 for more than 160 passages over a period of 3 years. Origin of the cultured cells was verified by comparison of their sequences of mitochondrial cytochrome oxidase subunit I genes (cox I) with the cox 1 sequence from cobia muscle tissue. The cell lines showed polyploidy. No mycoplasma contamination was detected. Susceptibility to grouper iridovirus was observed for the CB cell line but not the CF cell line. Both cell lines expressed green fluorescent protein after being transfected with green fluorescent reporter gene driven by the cytomegalovirus promoter. 相似文献
805.
Xiaoyun Zhou Khalid Abbas Mingyun Li Libao Fang Su Li Weimin Wang 《Aquaculture International》2010,18(3):349-359
To determine the cytotype with better traits for the aquaculture practices of the dojo loach Misgurnus anguillicaudatus from the viewpoint of fish farming improvement, factorial crosses (2n♀ × 2n♂, 2n♀ × 4n♂, 4n♀ × 2n♂, 4n♀ × 4n♂) were conducted
between natural diploids (D) and tetraploids (T), producing DD, DT, TD, and TT groups (female listed first). The potential
benefits of the different cytotypes in culture were evaluated by comparing growth performance and survival rate for a 15-month
rearing trial under the same production conditions. The average fertilization rate in DT and TT was significantly lower than
in the DD and TD groups, possibly indicating the poor fertilizing capacity of the tetraploid sires. Survival rate in DT and
TD was slightly lower than in DD but significantly higher than in the TT groups. Tetraploid females produced obviously larger
eggs than diploids and, subsequently, significantly longer initial body length of TT and TD than DD and DT fry. However, from
the second month of the growth trial, TT suffered higher mortality than other cytotypes, which significantly influenced morphometric
growth parameters. The TD group exhibited superior growth performance throughout the experiment. The mean body length of DT
was comparable with that of DD fish during the first 7 months but began to outgrow DD from the 9th month. This study suggests
that the relatively better growth of tetraploid and higher survival rate of diploid can be integrated via inter-ploidy hybridization
to get TD triploids with better culture traits. 相似文献
806.
Snježana Zrnčić Dražen Oraić Ivana Giovanna Zupičić Željko Pavlinec Dragan Brnić Žaklin Acinger Rogić Ivica Sučec Dieter Steinhagen Mikolaj Adamek 《Journal of fish diseases》2020,43(6):673-685
Common carp (Cyprinus carpio) is a very important fish species for warm-water aquaculture in Croatia. All Croatian carp farms are subjected to a surveillance programme for the presence of koi herpesvirus (KHV), causing a deadly disease called koi herpesvirus disease (KHVD). However, there is no surveillance for other viral pathogens of importance like carp edema virus (CEV), a causative agent of koi sleepy disease (KSD). During regular testing within the KHVD surveillance programme, we tested samples for CEV simultaneously. The screening indicated possible outbreaks of KHVD and KSD. During 2016, KHVD broke out in an isolated area and soon thereafter a KHV eradication programme was successfully performed. However, during 2018 and 2019, two additional mortality events occurred in lakes in the southern part of Croatia during the spring. Samples from both events tested positive for CEV. An epidemiological investigation confirmed the introduction of infected carps from an infected farm to one of the lakes. To prevent the spreading of CEV into open waters, it is of utmost importance to introduce CEV testing before fish movement or to perform regular testing of all carp farms in the country to determine CEV prevalence for the purpose of implementation of control measures. 相似文献
807.
Stocking density is a biotic factor affecting the production of cultivated animals in aquaculture. Herein, a rearing trial was conducted to investigate the impact of stocking density on the survival, growth performance and physical injury of Marsupenaeus japonicus juveniles in a flowing water aquaculture system. Five stocking densities were examined in this study, that is, 10, 20, 40, 80 and 160 individuals/m2. Throughout the experiment, ammonia nitrogen and nitrite concentrations ranged from 0.02 ± 0.006 mg/L to 0.08 ± 0.035 mg/L and 0.002 ± 0.001 mg/L to 0.076 ± 0.021 mg/L respectively. The survival rate, specific growth rate (SGR), weight gain (WG), absolute growth rate (AGR) and coefficient of variation for weight (CV) across the stocking densities ranged from 90.38 ± 3.20% to 94.33 ± 4.73%, 1.42 ± 0.16%/day to 1.53 ± 0.05%/day, 1.09 ± 0.19 g to 1.15 ± 0.16 g, 0.018 ± 0.003 g/day to 0.019 ± 0.004 g/day and 16.21 ± 5.78% to 35.09 ± 10.68% respectively. Within the investigated densities, the survival rate and the abovementioned growth parameters were not significantly (p > .05) affected by the stocking density, consequently, a higher stocking density resulted in a significantly (p < .05) greater final biomass. The results regarding physical injury showed that the antennal breakage rate displayed a tendency of a positive correlation with the stocking density. Overall, the current study provides basic data for establishing a viable intensive farming system for M. japonicus and a promising indicator for easily assessing the crowding stress status of M. japonicus. 相似文献
808.
Gang Luo Xiaojin Xu Lingmin Zhao Yingxue Qin Lixing Huang Yongquan Su Qingpi Yan 《Journal of fish diseases》2019,42(7):991-1000
Interaction between bacterial pathogen and aquatic animal host is exceedingly complex, which involves large dynamic changes in gene expression during different stages of the disease. However, research on identifying key virulence genes based on the dynamics of gene expression changes of a one‐sided bacterial pathogen in tissue has not been reported so far across different stages of infectious disease. The clpV for the T6SS of Pseudomonas plecoglossicida was identified for a candidate for key virulence gene based on dynamic changes of gene expression. For the Epinephelus coioides infected using clpV‐RNAi strain, no deaths were observed up to 20 dpi. The spleens, kidneys and livers of all the E. coioides that received clpV‐RNAi strain failed to develop visible nodules at 5–8 dpi, with the swelling gradually disappearing. The burdens of clpV‐RNAi strain in the spleen and blood were greatly reduced at most of the time points after injection, and the burdens of clpV‐RNAi strain in the head kidneys and trunk kidneys also had a sharp reduction from 72 to 120 hpi. This paper provides a new insight into the discovery of key virulence genes of pathogens in infected tissue systems. 相似文献
809.
Hugo E. Ramírez-Guerra Enrique Márquez-Ríos Guadalupe M. Suárez-Jiménez Ofelia Rouzaud-Sández María E. Lugo-Sánchez Juan C. Ramírez-Suárez 《Journal Of Aquatic Food Product Technology》2019,28(3):275-286
Physicochemical and structural properties of soluble jumbo squid (Dosidicus gigas) elastin recovered from skin by-products were evaluated. The molecular weight of isolated elastin was ~40 kDa with an isoelectric point (pI) between 9 and 10. Aspartic, glutamic, arginine, proline, glycine, and lysine amino acids were the most abundant in squid elastin, whereas the hydroxyproline absence, ~0.7% cysteine content, and the calculated 0.35 isoleucine/leucine ratio were used as purity index. Total and reactive sulfhydryl contents were similar (247.0 ± 5.1 vs 242.0 ± 7.5 μmol mg?1 of protein, P ≥ 0.05) in purified squid elastin but surprisingly higher than previously reported in other elastins. On the other hand, the secondary structures of squid elastin analyzed by Fourier transform infrared spectroscopy (FTIR) were ~45% β-sheets, ~15% α-helices, ~10% β-turns, and ~30% undefined structures. In addition, squid elastin experienced glass transition at 82.01 ± 0.01ºC, denaturation temperature at 110.45 ± 0.64ºC, and aggregation at 197.5 ± 0.23ºC. In conclusion, the prevalence of charged amino acids and pI of squid elastin can facilitate its solubilization in hydrophilic systems, whereas the secondary structure profile and thermostability are desirable features in proteins used for biopolymer designs such as food biofilms or barrier systems. 相似文献
810.
Zhijie Lu Zhendong Qin Vijayaraman Sarath Babu Chengkai Ye Guomao Su Jiabo Li Guang Yang Haiyang Shen Gan Pan Li Lin 《Aquaculture Research》2019,50(9):2635-2645
The freshwater prawn, Macrobrachium rosenbergii naturally lives in the freshwater, though it migrates to the brackish water environment during spawning that claimed to be resistant on a broad range of saline fluxes. However, little is known about the osmoregulatory patterns and the effect of an enzyme glutamine synthetase (GS) in M. rosenbergii under stress. Here, we described the identification and functional characterization of GS from M. rosenbergii (Mr‐GS) at molecular and protein levels. The identified Mr‐GS was comprised of 361 amino acids that phylogenetically shared the highest identity with other crustaceans and predicted to contain Gln‐synt_C and Gln‐synt_N domains at the respective terminal regions. Tissue distribution analysis in M. rosenbergii revealed that the Mr‐GS was highly expressed in muscle, and commonly existed in other examined tissues in the following order gills > heart > stomach > brain > haemolymph. Whereas, the mRNA of Mr‐GS was significantly up‐regulated in the muscle and gill tissues following challenges with either hyper (0 → 13‰), or hypo (13 → 0‰) osmotic stress at 3, 6 and 12 hr. Furthermore, the level of Glutamine concentration was positively correlated with the GS mRNA and protein expression patterns in hyper‐osmotic stress, whereas in hypo‐osmotic stress a slight decrease in the gills and maintained a level in the muscle tissues at 3, 6 and 12 hr post‐treatments. Our findings suggest that Mr‐GS potentially exhibited the osmoregulation responses in the gill and muscle tissues of M. rosenbergii throughout the time of osmotic stress, which will benefit for future study on osmoregulation. 相似文献