An investigation on bloom dynamics of Alexandrium catenella and A. pacificum and toxin accumulation in shellfish along the coast of Qinhuangdao, China.

The dinoflagellate genus Alexandrium comprises most of the toxic bloom-forming species producing paralytic shellfish toxins (PSTs) in the sea. Recently, repeated paralytic shellfish poisoning episodes have been recorded in Qinhuangdao located at the west coast of the Bohai Sea. To elucidate the relationship between toxic Alexandrium blooms and the poisoning episodes, a year-round investigation was carried out in this region from July 2020 to July 2021.

The complete mitochondrial genome of (Mactridae).

The whole mitochondrial genome sequence of (Reeve, 1854) was determined. It had a total length of 16,848 bp and it contained 12 protein coding genes, 2 ribosome RNA genes, and 22 transfer RNA genes. The base composition was 25.

Microalgal Microscale Model for Microalgal Growth Inhibition Evaluation of Marine Natural Products.

Marine organisms especially sessile invertebrates, such as soft corals, gorgonians and sponges, can survive in the competitive environment mainly relying on their second metabolites with chemoecological effects including allelopathy and algal growth inhibition. It is well known that the microscale models are urgently needed in marine chemoecology assessment to evaluate the algal growth inhibition activity of trace quantity natural products. In this work, a microalgal growth inhibition model was established for microalgal inhibition evaluation of marine natural products with 96-well microplate by automatic fluorescence observation using microplate reader.

Description of a catalase gene involved in responses to temperature stress.

Catalase (CAT) is an antioxidant enzyme that plays a significant role in cellular protection against oxidative damage by degradation of hydrogen peroxide to oxygen and water. In the present study, the complete CAT cDNA sequence of was identified through expressed sequence tags (EST) analysis and the rapid amplification of cDNA ends (RACE) technique. The nucleotide sequence of CAT cDNA consisted of 1,816 bp with a 1,434 bp open reading frame (ORF), encoding a polypeptide of 477 amino acid residues, which possessed significant homology to other known plant CATs.

Apoptosis induced by yessotoxins in Hela human cervical cancer cells in vitro.

To investigate the apoptotic effects of an extract of red-tide algae, Protoceratium reticulatum, on HeLa cells, we used liquid chromatography-tandem mass spectrometry, optical microscopy, Hoechst 33342/propidine iodide staining, and DNA gel electrophoresis to analyze its constituents and toxicity, as well as rhodamine 123 staining to investigate changes in mitochondrial membrane potential. Analysis showed that the P. reticulatum extract contained the yessotoxins (YTXs) homo-YTX, 45-OH-YTX and 45-OH-homo-YTX.

Protective roles of cornuside in acute myocardial ischemia and reperfusion injury in rats.

Cornuside is a secoiridoid glucoside isolated from the fruit of Cornus officinalis SIEB. et ZUCC. In this study, we investigated the anti-myocardial ischemia and reperfusion (I/R) injury effects of cornuside in vivo and elucidated the potential mechanism.

[Effects of two organic pollutants on biomarker system of fish Lateolabrax japonicus and the pollution assessment].

Responses of a select suite of protective enzymes in Lateolabrax japonicus including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx), reduced glutathione (GSH) glutathione S-transferase (GST), nitric oxide synthase (iNOS) in liver tissue and brain acetylcholinesterase (AChE), which could work as sensitively biochemical biomarkers were analyzed when exposed to different concentrations of sodium dodecylbenzene sulfonate (SDBS) and benzo[a]pyrene (B[a]P) under controlled laboratory conditions. Results showed that: (1) The biochemical biomarkers included in this investigation, different responses occurred in the enzymatic activities when exposed to different pollutants: the activities of SOD, GST, Gpx and GSH content were significantly induced by B[a]P (p < 0.05) while others present little different as compared to the control.

[Allelopathic effect of Corallina pilulifera on Heterosigma akashiwo and its responses to UV-B irradiation].

By the method of co-culture and using cell density as the main indicator, this paper studied the allelopathic effect of Corallina pilulifera on Heterosigma akashiwo and its responses to UV-B irradiation. Under normal condition, the fresh tissue and aqueous extracts of C. pilulifera had significant inhibitory effects on the growth of H.

[Effects of artificial seawater with different N/P ratio on early development of Laminaria japonica embryo spore].

The embryo spores of Laminaria japonica were cultured in artificial seawater with different N/P ratio to observe their early development. 80 percent of the spores cultivated in whole-ingredient artificial seawater developed normally, but the time of spore germination and gametophyte formation was lagged significantly and the amount of female gametes was significantly higher than that of male gametes (P<0.001), as compared to the control cultivated in natural seawater.

[Acute toxicity effects of three red tide algae on Brachionus plicatilis].

Acute toxicity testing method was used to study effects of different density of Prorocentrum donghaiense, Heterosigma akashiwo and Alexandrium tamarense on mortality rates and population growth parameter of Brachionus plicatilis under controlled experimental conditions. Results showed that 24 h LC50 values of Prorocentrum donghaiense, Heterosigma akashiwo and Alexandrium tamarense treatment to mortality rate of Brachionus plicatilis were 3.56, 1.

[Response of interspecific competition between Ulva pertusa and Grateloupia filicina to UV-B irradiation enhancement].

The interspecific competition between Ulva pertusa and Grateloupia filicina and it's response to the UV-B irradiation enhancement were analyzed using mono-culture and co-culture methods. The study adopted reasonable experimental design and took biomass as the main examined index. Results showed that the relation of interspecific competition included both allelopathy effect and nutrient competition.

[Allelopathic effects of Corallina pilulifera on red tide microalgae Heterosigma akashiwo].

Different concentration methanol-, acetone-, ether-, and chloroform extracts of Corallina pilulifera were used to study their growth inhibitory effects on red tide microalgae Heterosigma akashiwo. The results showed that methanol extract at relatively higher concentrations had the highest growth inhibitory activity and killed all H. akashiwo cells, while the other three kinds of organic solvent extracts had no apparent inhibitory effects, suggesting that the growth inhibitory substances in C.

The response of the early developmental stages of Laminaria japonica to enhanced ultraviolet-B radiation.

The responses of the early development of Laminaria japonica collected from Kiaochow Bay in China to enhanced ultraviolet-B radiation (UV-B, 280-320 nm) were studied in the laboratory. The low UV-B radiations (11.7-23.

[Effects of red tide microalgae Alexandrium tamarense on the life history of rotifer Brachionus plicatilis].

In this paper, life-table method was used to study the effects of different concentration Alexandrium tamarense on the durations of different development stages of Brachionus plicatilis and the characters of its population growth. The results showed that A. tamarense had significant effects on the growth and development of B.

Cryopreservation of gametophytes of Laminaria japonica (phaeophyta) with two-step cooling: interactions between variables related to post-thaw survival.

Little attention has been given to the effect of interactions between different cryogenic parameters on the viability of cryopreserved algae. Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen by two-step cooling, and interactions were tested for optimizing the cooling protocol and improving freeze-tolerance. UNOVA of a general linear model suggested that interactions between both cooling rate and holding time and between holding temperature and holding time significantly affected the survival of thawed gametophytes.

Mass transport model of ions within biofilms under the effect of external field.

A mass transport model was developed to predict the transport rate of ions within biofilms, which was experimentally verified using the fluxes of NH4+ and Ca2+ through the heterotrophic biofilms with the thickness varying from 230 to 1430 microm under the effect of external field in the range of -20 V/m to 60 V/m. It is found that the result predicted by the model is in agreement with the experimentally obtained one, with the error less than 5 percent for the thin biofilms. The error increases with the increase of the biofilm thickness.

Effect of alginic acid decomposing bacterium on the growth of Laminaria japonica (Phaeophyceae).

We collected the diseased blades of Laminaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identified as Alteromonas espejiana. This bacterium was applied as the causative pathogen to infect the blades of L. japonica under laboratory conditions.

3-(4-Amino-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-3-yl)pyridinium chloride.

In the title compound, C(7)H(8)N(5)S(+)·Cl(-), the dihedral angle formed by the pyridine ring with the triazole ring is 10.0 (1)°. There are weak inter-molecular hydrogen-bond inter-actions in the crystal structure, involving the NH and NH(2) groups as donors, and the chloride anion, the S atom in the thio-ketone group and the unsubstituted ring N atom as acceptors.

Effects of UV-B radiation on the growth interaction of Ulva pertusa and Alexandrium tamarense.

Enhanced UV-B (280 - 320 nm) radiation resulting from ozone depletion is one of global environmental problems. Not only marine organisms but also marine ecosystems can be affected by enhanced UV-B radiation. The effects of UV-B radiation on interaction of macro-algae and micro-algae were investigated using Ulva pertusa Kjellman and Alexandrium tamarense as the materials in this study.

Effects of scorpion venom bioactive polypolypeptides on platelet aggregation and thrombosis and plasma 6-keto-PG F1alpha and TXB2 in rabbits and rats.

Effects of scorpion venom active polypeptide (SVAP) from scorpion venom of Buthus Martensii Karsch of Chinese on platelet aggregation in ex vivo and vitro in rabbits, thrombosis in carotid artery of rats and plasma 6-keto-PG F1alpha and TXB2 in rats were studied by the turbidimetry, the duplicated thrombosis model by electrostimulation and RIA, respectively. The results showed that SVAP 0.125, 0.