Climate-driven expansion of Takayama acrotrocha blooms: First outbreak along the north coast of Shandong, China linked to intense precipitation and warming.

In Summer 2024, a dinoflagellate bloom broke out in the Bohai Sea along the north coast of Shandong peninsula. By approaches of morphological observation, pigment analysis and targeted gene sequencing, the bloom causative species was identified as dinoflagellate Takayama acrotrocha. The satellite imagery indicated that the bloom lasted from August 24 to September 8, and distributed mainly in the coastal waters extending from the Yellow River estuary to Yantai and Weihai, marking the northward expansion of this algal species along the coast of China.

Impacts of Kuroshio intrusion on algal blooms in the coastal waters adjacent to the Changjiang River estuary.

The Nearshore Kuroshio Branch Current (NKBC) in the East China Sea can extend across the continental shelf and reach the coastal waters adjacent to the Changjiang River estuary (CRE), where intensive blooms of dinoflagellates have been recorded for more than two decades. To understand the seasonal dynamics of dinoflagellate blooms and their relationship with NKBC intrusion in this region, monthly investigations were conducted from February 2015 to January 2016. During the investigations, a bloom of dinoflagellate Prorocentrum donghaiense, accompanied by diatom Thalassiosira spp.

Strong interannual variation of green tides in the southern Yellow Sea: Crucial factors and implications on management strategies.

In the Southern Yellow Sea (SYS), recurrent large-scale green tides of Ulva prolifera have been recorded since 2007, and nori cultivation rafts in Subei Shoal are generally considered as the major source of floating green algae. The control measures in Subei Shoal, however, didn't solve the problem, and the magnitude of green tides (as indicated by the coverage area of floating green algae) exhibited strong interannual variation. In this study, the dynamics of green tides in the SYS were analyzed using the data of remote sensing from 2017 to 2023, and the factors closely related to the magnitude of green tides were analyzed.

An unusual winter bloom of dinoflagellates with notable damage to kelp cultivation around Shandong peninsula, China.

In the coastal waters around Shandong peninsula, an unprecedented winter bloom of dinoflagellates Gonyaulax polygramma and Akashiwo sanguinea occurred in 2021 from late November to early December. The bloom affected a wide area of coastal waters extending from west to east along the northern Shandong peninsula and had a devastating blow to the kelp cultivation industry. Based on the remote-sensing data, the initiation of the bloom was traced back to the region adjacent to the mouth of the Yellow River in Laizhou Bay, where enhanced freshwater discharge from the Yellow River was recorded from September to November.

Potential roles of hydroxybenzoate paralytic shellfish toxins in modulating toxin biokinetics in scallops.

Paralytic shellfish toxins (PSTs) produced by some marine dinoflagellates can cause severe human intoxication via vectors like bivalves. Toxic dinoflagellate Gymnodinium catenatum produce a novel group of hydroxybenzoate PSTs named GC toxins, but their biokinetics in bivalves haven't been well examined. In this experiment, we analyzed PSTs in bay scallops Argopecten irradians exposed to G.

Marked shifts of harmful algal blooms in the Bohai Sea linked with combined impacts of environmental changes.

The Bohai Sea, a semi-enclosed inland sea in China and an important mariculture region, has experienced extensive harmful algal blooms (HABs) and their negative impacts for several decades. To investigate the changes of HABs and their potential drivers over time and space, a dataset of 230 HAB events (1952-2017), along with corresponding environmental data (1990-2017) was compiled. The frequency of HAB events in the Bohai Sea has increased over time but plateaued in the last decade, and our analysis showed that history of HABs in the Bohai Sea could be categorized into three periods based on their frequency, scale, and HAB-forming species.

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.

Toxin production of dinoflagellate Gymnodinium catenatum isolated from the East China Sea.

Dinoflagellate Gymnodinium catenatum is an important producer of paralytic shellfish toxins (PSTs), including a novel group of hydroxybenzoate derivatives named GC toxins. In the East China Sea, G. catenatum has been considered as the causative agent for several paralytic shellfish poisoning (PSP) episodes, yet the knowledge on their toxin production was still quite limited.

Green Tides in the Yellow Sea Promoted the Proliferation of Pelagophyte .

Harmful algal blooms formed by fast-growing, ephemeral macroalgae have expanded worldwide, yet there is limited knowledge of their potential ecological consequences. Here, we select intense green tides formed by in the Yellow Sea, China, to examine the ecological consequences of these blooms. Using 28-isofucosterol in the surface sediment as a biomarker of green algae, we identified the settlement region of massive floating green algae in the area southeast of the Shandong Peninsula in the southern Yellow Sea.

The dinoflagellate Alexandrium catenella producing only carbamate toxins may account for the seafood poisonings in Qinhuangdao, China.

An outbreak of paralytic shellfish poisoning, recorded in April 2016 in Qinhuangdao China, was suspected to be caused by a toxic species in genus Alexandrium. Shortly after the poisoning outbreak, shellfish and net-concentrated phytoplankton samples were collected from the Bohai Sea, and analysed using high performance liquid chromatography coupled with fluorescence detection. Paralytic shellfish toxins (PSTs) were detected in both phytoplankton and shellfish samples, with similar toxin profiles dominated by carbamate toxins.

Biokinetics and biotransformation of paralytic shellfish toxins in different tissues of Yesso scallops, Patinopecten yessoensis.

Paralytic shellfish toxins (PSTs) are a group of natural toxic substances often found in marine bivalves. Accumulation, anatomical distribution, biotransformation and depuration of PSTs in different tissues of bivalves, however, are still not very well understood. In this study, we investigated biokinetics and biotransformation of PSTs in six different tissues, namely gill, mantle, gonad, adductor muscle, kidney, and digestive gland, in Yesso scallops Patinopecten yessoensis exposed to a toxic strain of dinoflagellate Alexandrium pacificum.

Distribution of Alexandrium pacificum cysts in the area adjacent to the Changjiang River estuary, China.

The coastal waters adjacent to the Changjiang River estuary (CRE) are characterized by nutrient pollution and recurrent harmful algal blooms. In this study, resting cysts of Alexandrium pacificum Litaker and A. catenella (Whedon & Kof.

Resting cysts of Alexandrium catenella and A. pacificum (Dinophyceae) in the Bohai and Yellow Seas, China: Abundance, distribution and implications for toxic algal blooms.

The Alexandrium tamarense species complex consists of 5 closely related species that are important bloom-forming dinoflagellates with a complex life cycle. The formation of resting cyst is a key strategy to resist harsh environmental conditions. In this study, the resting cysts of two major bloom-forming species of the A.

Spatiotemporal variation of paralytic shellfish toxins in the sea area adjacent to the Changjiang River estuary.

The Changjiang (Yangtze River) River estuary (CRE) and its adjacent coastal waters is a notable region for nutrient pollution, which results in severe problems of coastal eutrophication and harmful algal blooms (HABs). The occurrence of HABs, particularly those of dinoflagellate Alexandrium spp. capable of producing paralytic shellfish toxins (PSTs), has an increasing risk of contaminating seafood and poisoning human-beings.

Resolving phytoplankton taxa based on high-throughput sequencing during brown tides in the Bohai Sea, China.

Large-scale blooms formed by pico-sized phytoplankton, which strongly inhibited feeding activity and growth of cultured scallops, have been recorded along the coast of Qinhuangdao in the Bohai Sea since 2009. Based on pigment profiles and clone library analysis of phytoplankton samples during the blooms, the major bloom-forming species was primarily identified as pelagophyte Aureococcus anophagefferens Hargraves et Sieburth, the causative species of intensive brown tides in the United States and South Africa. Due to the indistinct morphological features of the bloom-forming microalgae and limited knowledge on the composition of phytoplankton communities, there were still disputes concerning the causative species of the blooms.

Contamination status of lipophilic marine toxins in shellfish samples from the Bohai Sea, China.

Lipophilic marine toxins in shellfish pose significant threats to the health of seafood consumers. To assess the contamination status of shellfish by lipophilic marine toxins in the Bohai Sea, nine species of shellfish periodically collected from five representative aquaculture zones throughout a year were analyzed with a method of liquid chromatography-tandem mass spectrometry (LC-MS/MS). Lipophilic marine toxins, including okadaic acid (OA), dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2), yessotoxin (YTX), homo-yessotoxin (homo-YTX), azaspiracids (AZA2 and AZA3), gymnodimine (GYM), and 13-desmethyl spirolide C (13-DesMe-C), were detected in more than 95 percent of the shellfish samples.

Cadmium: Toxic effects on placental and embryonic development.

Cadmium is a non-essential trace metal that has strong teratogenic and mutagenic effects in living organisms. The content is more highly enriched in women than in men and can enter the embryo through the placenta and destroy the placenta's morphological structure, resulting in fetal growth restriction. In this report, we review published data linking pregnancy exposure to cadmium to placenta and fetal growth and development toxicity and summarize the related mechanisms.

Genetic evidence in tracking the origin of Ulva prolifera blooms in the Yellow Sea, China.

Recurrent green tides have been recorded in the Yellow Sea for 11 consecutive years. The origin of floating green algae in the Yellow Sea, however, remains a subject of debate. Previous studies suggest that the major bloom-forming green alga Ulva prolifera represent a unique ecotype different from other attached populations of U.

Neuroprotective effects of epoxyeicosatrienoic acids.

Eicosatrienoic acids (EETs) are a class of intermediates produced during arachidonic acid metabolism mediated by cytochrome P450 epoxygenases that exert multiple physiological effects on the nervous system. EETs promote three metabolic processes, including esterification, hydrolysis and degradation or extension. EETs are hydrolyzed by soluble epoxide hydrolase (sEH) to form corresponding diols, thereby reducing their biological activity.

Analysis of sterols in selected bloom-forming algae in China.

Sterols, a group of stable lipid compounds, are often used as biomarkers in marine biogeochemical studies to indicate sources of organic matter. In this study, sterols in 13 species of major bloom-forming algae in China, which belong to Dinophyceae, Bacillariophyceae, Ulvophyceae, and Pelagophyceae, were analyzed with gas chromatography-mass spectrometry (GC-MS) to test their feasibility in representing different types of harmful algal blooms (HABs). It was found that (24Z)-stigmasta-5,24-dien-3β-ol (28-isofucosterol) was a major sterol component in green-tide forming macroalga Ulva prolifera.

14,15-EET Suppresses Neuronal Apoptosis in Ischemia-Reperfusion Through the Mitochondrial Pathway.

Neuronal apoptosis mediated by the mitochondrial apoptosis pathway is an important pathological process in cerebral ischemia-reperfusion injury. 14,15-EET, an intermediate metabolite of arachidonic acid, can promote cell survival during ischemia/reperfusion. However, whether the mitochondrial apoptotic pathway is involved this survival mechanism is not fully understood.

Prokaryotic expression and polyclonal antibody preparation of a novel Rab-like protein mRabL5.

Rab GTPases, which belong to the Ras superfamily, represent a group of small molecular weight GTP binding proteins that are involved in various steps along the exocytic and endocytic pathways. We first identified mRabL5 (GenBank Accession No. NP_080349), a novel Mus musculus Rab-like protein, present as a Golgi-associated protein.