Humanization and characterization of an anti-ciguatoxin CTX3C monoclonal antibody.

Ciguatera poisoning (CP), caused by ciguatoxins (CTXs), is one of the most common food-borne diseases, affecting more than 50,000 people each year. In most cases, CP are managed with symptomatic and supportive remedies, and no specific treatment has been devised. In this study, toward the development of therapeutic antibodies for CP, we examined to humanize mouse anti-CTX3C antibody 10C9 (m10C9), which exhibited neutralizing activity against ciguatoxin in vitro and in vivo.

Factors related to the surgical outcomes of type I tympanoplasty for tympanic membrane perforation in children.

Background: Factors related to surgical outcomes of type I tympanoplasty for tympanic membrane (TM) perforation in children are controversial.

Objectives: To investigate factors related to anatomical results of type I tympanoplasty for TM perforation 1 year after surgery.

Material And Methods: We examined 68 ears.

Glancing at the birth of a galaxy of scientists from Rikō Majima.

Rikō Majima published seven papers in this journal, and seeing these papers and their surrounding contexts allows us to glance at the birth of a galaxy of scientists.

Cell immunolocalization of ciguatoxin-like compounds in the benthic dinoflagellate Gambierdiscus australes M. Chinain & M.A. Faust by confocal microscopy.

Dinoflagellates of the genera Gambierdiscus and Fukuyoa are able to produce potent neurotoxins like ciguatoxins (CTXs), which, after biooxidation in fish, are responsible for ciguatera intoxication. An isolate of G. australes from the Canary Islands, that revealed the presence of CTX-like compounds by immunosensing tools, was studied by immunocytochemistry to localize intracellular CTX-like compounds, using 8H4 monoclonal antibody that specifically recognizes the right wing of CTX1B and CTX3C analogues.

A smartphone-controlled amperometric immunosensor for the detection of Pacific ciguatoxins in fish.

Ciguatoxins (CTXs) are marine neurotoxins produced by microalgae of the genera Gambierdiscus and Fukuyoa. CTXs may reach humans through food webs and cause ciguatera fish poisoning (CFP). An immunosensor for the detection of Pacific CTXs in fish was developed using multiwalled carbon nanotube (MWCNT)-modified carbon electrodes and a smartphone-controlled potentiostat.

Cinnamoyl amide type chiral P,olefin ligands for Pd-catalyzed reactions.

We synthesized cinnamoyl amide type chiral P,olefin ligand ()-4. We successfully obtained separable diastereomers of 4d and demonstrated Pd-catalyzed asymmetric allylic substitution reactions of indoles using (,a)-4d as a chiral ligand with high enantioselectivities (up to 98% ee).

Prognostic factors of early-onset otitis media with effusion in children treated using tympanostomy.

Background: Predicting the prognosis of early-onset otitis media with effusion (OME) in children is difficult.

Objectives: To investigate the prognostic factors of OME in children undergoing tympanostomy at 1 year of age.

Material And Methods: We examined 66 children (123 ears) followed up to 6 years of age.

Long-term outcomes in children with and without cleft palate treated with tympanostomy for otitis media with effusion before the age of 2 years.

Background: Long-term outcomes of children with and without cleft palate receiving early treatment for otitis media with effusion (OME) are unclear.

Objectives: To compare long-term otological and audiological outcomes between children with and without cleft palate treated with tympanostomy for OME before the age of 2 years.

Material And Methods: Ninety-five children (180 ears) with cleft palate (study group) and 97 children (185 ears) without (control group) were followed-up to a maximum age of 7 years.

Rapid detection of ciguatoxins in Gambierdiscus and Fukuyoa with immunosensing tools.

Consumption of seafood contaminated with ciguatoxins (CTXs) leads to a foodborne disease known as ciguatera. Primary producers of CTXs are epibenthic dinoflagellates of the genera Gambierdiscus and Fukuyoa. In this study, thirteen Gambierdiscus and Fukuyoa strains were cultured, harvested at exponential phase, and CTXs were extracted with an implemented rapid protocol.

Addressing the Analytical Challenges for the Detection of Ciguatoxins Using an Electrochemical Biosensor.

The importance of ciguatoxins (CTXs) in seafood safety and their emerging occurrence in locations far away from tropical areas highlight the need for simple and low-cost methods for the sensitive and rapid detection of these potent marine toxins to protect seafood consumers. Herein, an electrochemical immunosensor for the detection of CTXs is presented. A sandwich configuration is proposed, using magnetic beads (MBs) as immobilization supports for two capture antibodies, with their combination facilitating the detection of CTX1B, CTX3C, 54-deoxyCTX1B, and 51-hydroxyCTX3C.

Rationally Designed Synthetic Haptens to Generate Anti-Ciguatoxin Monoclonal Antibodies, and Development of a Practical Sandwich ELISA to Detect Ciguatoxins.

"Ciguatera" fish poisoning (CFP) is one of the well-known food poisoning caused by the ingestion of fish that have accumulated trace amounts of ciguatoxins (CTXs). CFP affects more than 50,000 individuals annually. The difficulty in preventing CFP comes from the lack of reliable methods for analysis of CTXs in contaminated fish, together with the normal appearance, taste, and smell of CTX-contaminated fish.

A convergent total synthesis of the kedarcidin chromophore: 20-years in the making.

The kedarcidin chromophore is a formidible target for total synthesis. Herein, we describe a viable synthesis of this highly unstable natural product. This entailed the early introduction and gram-scale synthesis of 2-deoxysugar conjugates of both L-mycarose and L-kedarosamine.

Highly Sensitive and Practical Fluorescent Sandwich ELISA for Ciguatoxins.

Ciguatera fish poisoning (CFP) caused by the consumption of fish that have accumulated ciguatoxins (CTXs) affects more than 50000 people annually. The spread of CFP causes enormous damage to public health, fishery resources, and the economies of tropical and subtropical endemic regions. The difficulty in avoiding CFP arises from the lack of sensitive and reliable analytical methods for the detection and quantification of CTXs in contaminated fish, along with the normal appearance, smell, and taste of fish contaminated with the causative toxins.

Transcriptomic Analysis of Ciguatoxin-Induced Changes in Gene Expression in Primary Cultures of Mice Cortical Neurons.

Ciguatoxins are polyether marine toxins that act as sodium channel activators. These toxins cause ciguatera, one of the most widespread nonbacterial forms of food poisoning, which presents several symptoms in humans including long-term neurological alterations. Earlier work has shown that both acute and chronic exposure of primary cortical neurons to synthetic ciguatoxin CTX3C have profound impacts on neuronal function.

Synthetic Studies on Presporolide, a Putative Enediyne Precursor of Sporolides.

A synthesis of the core framework of presporolide, which possesses both a strained bicyclo[7.3.0]dodecadiyne moiety and a distinctive macrolactone structure, is reported.

Characterization of Cell Wall α-1,3-Glucan-Deficient Mutants in Isolated by a Screening Method Based on Their Sensitivities to Congo Red or Lysing Enzymes.

We previously reported that sensitivity to Congo Red (CR) or Lysing Enzymes (LE) is affected by the loss of cell-wall α-1,3-glucan (AG) in . We found that the amount of CR adsorbed to AG was significantly less than the amount adsorbed to β-1,3-glucan (BG) or chitin, suggesting that loss of cell-wall AG would increase exposure of BG on the cell surface, and thereby increase the sensitivity to CR. Generally, fungal BGs are known as biological response modifiers because of their recognition by Dectin-1 receptors in human immune systems.

Competent Route to Unsymmetric Dimer Architectures: Total Syntheses of (-)-Lycodine and (-)-Complanadines A and B, and Evaluation of Their Neurite Outgrowth Activities.

Valuable synthetic routes to the Lycopodium alkaloid lycodine (1) and its unsymmetric dimers, complanadines A (4) and B (5), have been developed. Regioselective construction of the bicyclo[3.3.

Total synthesis and related studies of large, strained, and bioactive natural products.

Our chemical syntheses and related scientific investigations of natural products with complex architectures and powerful biological activities are described, focusing on the very large 3 nm-long polycyclic ethers called the ciguatoxins, highly strained and labile chromoprotein antitumor antibiotics featuring nine-membered enediyne cores, and extremely potent anthelmintic macrolides called the avermectins.

Total synthesis of avermectin B1a revisited.

Avermectins were isolated as compounds possessing anthelmintic activity from the culture broth of Streptomycesavermitilis by Ōmura and co-workers. Owing to their potent anthelmintic and insecticidal activities, as well as their unique pentacyclic architecture, the avermectin family attracted keen interest from synthetic organic chemists. We have recently completed a more efficient and straightforward total synthesis of avermectin B1a, as compared with previous syntheses.

Total Synthesis of Limonin.

Limonoids are highly oxygenated C13α-triterpenes and common secondary metabolites. Several hundred congeners have been isolated to date. The first total synthesis of (±)-limonin, the flagship congener of the limonoids, is now reported and features 1) a tandem radical cyclization generating the BCD ring system with the C13α configuration that is essential to the limonoids and a Robinson annulation to construct the limonoid androstane framework, 2) a singlet-oxygen cycloaddition and a Baeyer-Villiger oxidation to synthesize the highly oxidized D ring, and 3) a Suárez reaction to construct the unique AA' ring system.

Chronic ciguatoxin treatment induces synaptic scaling through voltage gated sodium channels in cortical neurons.

Ciguatoxins are sodium channels activators that cause ciguatera, one of the most widespread nonbacterial forms of food poisoning, which presents with long-term neurological alterations. In central neurons, chronic perturbations in activity induce homeostatic synaptic mechanisms that adjust the strength of excitatory synapses and modulate glutamate receptor expression in order to stabilize the overall activity. Immediate early genes, such as Arc and Egr1, are induced in response to activity changes and underlie the trafficking of glutamate receptors during neuronal homeostasis.

Synthetic ciguatoxin CTX 3C induces a rapid imbalance in neuronal excitability.

Ciguatera is a human global disease caused by the consumption of contaminated fish that have accumulated ciguatoxins (CTXs), sodium channel activator toxins. Symptoms of ciguatera include neurological alterations such as paraesthesiae, dysaesthesiae, depression, and heightened nociperception, among others. An important issue to understand these long-term neurological alterations is to establish the role that changes in activity produced by CTX 3C represent to neurons.