Read by QxMD icon Read


Roy W A Peake, Victoria Y Zhang, Nina Azcue, Christina E Hartigan, Aida Shkreta, Jasmina Prabhakara, Charles B Berde, Mark D Kellogg
Neosaxitoxin, a member of the saxitoxin family of paralytic shellfish poisoning toxins, has shown potential as an effective, long-acting, anesthetic. We describe the development and validation of a highly sensitive method for measurement of neosaxitoxin in human plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS) and provide evidence for its use in a human pharmacokinetic study. Samples were prepared using cation exchange solid phase extraction followed by hydrophilic interaction liquid chromatography and MS/MS detection in positive electrospray ionization mode...
October 1, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Delu Zhang, Siyi Liu, Jing Zhang, Jian Kong Zhang, Chunxiang Hu, Yongding Liu
Aphantoxins, neurotoxins or paralytic shellfish poisons (PSPs) generated by Aphanizomenon flos-aquae, are a threat to environmental safety and human health in eutrophic waters worldwide. The molecular mechanisms of neurotoxin function have been studied; however, the effects of these neurotoxins on oxidative stress, ion transport, gas exchange, and branchial ultrastructure in fish gills are not fully understood. Aphantoxins extracted from A. flos-aquae DC-1 were detected by high-performance liquid chromatography...
August 2016: Aquatic Toxicology
De Lu Zhang, Si Yi Liu, Jing Zhang, Jian Kun Zhang, Chun Xiang Hu, Yong Ding Liu
Aphantoxins from Aphanizomenon flos-aquae are frequently identified in eutrophic waterbodies worldwide. These toxins severely endanger environmental safety and human health due to the production of paralytic shellfish poisons (PSPs). Although the molecular mechanisms of aphantoxin neurotoxicity have been studied, many questions remain to be resolved such as in vivo alterations in branchial histology and neurotransmitter inactivation induced by these neurotoxins. Aphantoxins extracted from a naturally isolated strain of A...
July 2016: Aquatic Toxicology
D P Rubio, L G Roa, D A Soto, F J Velasquez, N A Gregorcic, J A Soto, M C Martinez, A M Kalergis, A E Vasquez
In the current communication we describe an innovative method to purify saxitoxin (STX), a toxin presents in contaminated muscle of Mylitus chilensis extracted in the southern part of Chile, using a liquid chromatographic methodology based on ionic pairs. The STX was extracted using HCl and treated with ammonium sulfate following a treatment with trichloroacetic acid and hexane/diethyl ether (97/3). The samples were analyzed by a semi-preparative HPLC in order to collect pure fractions of STX and these fractions were eluted in solid-phase cationic interchange SCX extraction columns...
December 15, 2015: Toxicon: Official Journal of the International Society on Toxinology
James P Rathmell, Gary Strichartz, Jonathan Wanderer
No abstract text is available yet for this article.
October 2015: Anesthesiology
José Patricio Casanova, Carlos Madrid, Marco Contreras, María Rodríguez, Mónica Vasquez, Fernando Torrealba
A growing body of evidence suggests that learned fear may be related to the function of the interoceptive insular cortex. Using an auditory fear conditioning paradigm in rats, we show that the inactivation of the posterior insular cortex (pIC), the target of the interoceptive thalamus, prior to training produced a marked reduction in fear expression tested 24h later. Accordingly, post-training anisomycin infused immediately, but not 6h after, also reduced fear expression tested the following day, supporting a role for the pIC in consolidation of fear memory...
January 1, 2016: Behavioural Brain Research
Jay S Templin, Matthew C Wylie, Joseph D Kim, Katherine E Kurgansky, Grzegorz Gorski, John Kheir, David Zurakowski, Gabriel Corfas, Charles Berde
BACKGROUND: Neosaxitoxin (NeoSTX) is a site-1 sodium channel blocker undergoing clinical trials as a prolonged-duration local anesthetic. Rat sciatic block and intravenous infusion models were used to assess efficacy and local and systemic toxicities for NeoSTX in saline (NeoSTX-Saline), bupivacaine (Bup), and their combination (NeoSTX-Bup). Exploratory studies evaluated the effects of addition of epinephrine to NeoSTX-Bup (NeoSTX-Bup-Epi). METHODS: Rats received percutaneous sciatic blocks with escalating doses of NeoSTX-Saline or NeoSTX-Bup...
October 2015: Anesthesiology
Laura A Lahaye, John F Butterworth
No abstract text is available yet for this article.
October 2015: Anesthesiology
Kimberly Lobo, Carolina Donado, Laura Cornelissen, Joseph Kim, Rebeca Ortiz, Roy W A Peake, Mark Kellogg, Mark E Alexander, David Zurakowski, Katherine E Kurgansky, James Peyton, Aykut Bilge, Karen Boretsky, Mary Ellen McCann, Charles B Berde, Joseph Cravero
BACKGROUND: Neosaxitoxin (NeoSTX) is a site-1 sodium channel blocker that produces prolonged local anesthesia in animals and humans. Under a Food and Drug Administration-approved phase 1 Investigational New Drug trial, the authors evaluated safety and efficacy of NeoSTX alone and combined with 0.2% bupivacaine (Bup) with and without epinephrine. METHODS: The authors conducted a double-blind, randomized, controlled trial involving healthy male volunteers aged 18 to 35 yr receiving two 10-ml subcutaneous injections...
October 2015: Anesthesiology
Andrew D Turner, Paul S McNabb, D Tim Harwood, Andrew I Selwood, Michael J Boundy
A single-laboratory validation study was conducted for the hydrophilic interaction-LC-MS/MS analysis of paralytic shellfish toxins (PSTs) in bivalve shellfish. The method was developed as an alternative to the precolumn oxidation AOAC 2005.06 and postcolumn oxidation AOAC 2011.02 LC with fluorescence detection methods, receptor binding assay AOAC 2011.27, as well as the mouse bioassay AOAC 959.08. PSTs assessed were saxitoxin, neosaxitoxin, deoxydecarbamoylsaxitoxin, decarbamoylsaxitoxin, decarbamoylneosaxitoxin, gonyautoxins 1-6, decarbamoylgonyautoxins 2-3, and N-sulfocarbamoyl gonyautoxins 2&3...
May 2015: Journal of AOAC International
Pedro R Costa, Alison Robertson, Michael A Quilliam
The marine dinoflagellate Gymnodinium catenatum has been associated with paralytic shellfish poisoning (PSP) outbreaks in Portuguese waters for many years. PSP syndrome is caused by consumption of seafood contaminated with paralytic shellfish toxins (PSTs), a suite of potent neurotoxins. Gymnodinium catenatum was frequently reported along the Portuguese coast throughout the late 1980s and early 1990s, but was absent between 1995 and 2005. Since this time, G. catenatum blooms have been recurrent, causing contamination of fishery resources along the Atlantic coast of Portugal...
April 2015: Marine Drugs
William A Bragg, Sharon W Lemire, Rebecca M Coleman, Elizabeth I Hamelin, Rudolph C Johnson
Saxitoxin (STX) and neosaxitoxin (NEO) are potent neurotoxins that cause paralytic shellfish poisoning (PSP). PSP typically occurs through the ingestion of bivalve shellfish that have consumed toxin producing dinoflagellates. Due to initial presentation of symptoms being nonspecific, a clinical measurement is needed to confirm exposure to these toxins. Our group has developed an online solid phase extraction hydrophilic interaction liquid chromatography (HILIC) method for the analysis of STX and NEO in human urine with tandem mass spectrometry...
June 1, 2015: Toxicon: Official Journal of the International Society on Toxinology
Huajuan Lin, Chaohua Zhang, Jianmeng Liao, Feng Yang, Saiyi Zhong, Peihong Jiang, Xiao Chen, Yuji Nagashima
Several species of crabs are resistant to paralytic shellfish toxins (PSTs) and/or pufferfish toxin, tetrodotoxin, regardless of toxification by the toxins. The shore crab Thalamita crenata, which inhabits Leizhou Peninsula, China, is tolerant to PST toxicity, and the hemolymph has neutralizing effects against the lethal activity of PST. In the present study, we investigated the PST neutralizing factors in the hemolymph from T. crenata and successfully separated PST-binding proteins by PST-ligand affinity chromatography...
June 1, 2015: Toxicon: Official Journal of the International Society on Toxinology
Valentin Manríquez, Daniela Castro Caperan, Rodrigo Guzmán, Michel Naser, Veronica Iglesia, Nestor Lagos
INTRODUCTION AND HYPOTHESIS: Neosaxitoxin is a phycotoxin whose molecular mechanism of action shows a reversible inhibition of voltage-gated sodium channels at the axonal level, impeding nerve impulse propagation. This study was designed to evaluate the clinical efficacy of neosaxitoxin as a long-acting pain blocker in the treatment of bladder pain syndrome (BPS). METHODS: Five patients with a diagnosis of BPS received a total dose of 80 µg of neosaxitoxin in an isoosmotic solution of 0...
June 2015: International Urogynecology Journal
José J Bustillos-Guzmán, Christine J Band-Schmidt, Lorena M Durán-Riveroll, Francisco E Hernández-Sandoval, David J López-Cortés, Erick J Núñez-Vázquez, Allan Cembella, Bernd Krock
The paralytic shellfish toxin (PST) profiles of Gymnodinium catenatum Graham have been reported for several strains from the Pacific coast of Mexico cultured under different laboratory conditions, as well as from natural populations. Up to 15 saxitoxin analogues occurred and the quantity of each toxin depended on the growth phase and culture conditions. Previous analysis of toxin profiles of G. catenatum isolated from Mexico have been based on post-column oxidation liquid chromatography with fluorescence detection (LC-FLD), a method prone to artefacts and non-specificity, leading to misinterpretation of toxin composition...
2015: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
De Lu Zhang, Si Yi Liu, Jing Zhang, Chun Xiang Hu, Dun Hai Li, Yong Ding Liu
Aphanizomenon flos-aquae secretes paralytic shellfish poisons (PSPs), termed aphantoxins, and endangers environmental and human health via eutrophication of water worldwide. Although the molecular mechanism of neuronal PSP toxicity has been well studied, several issues remain unresolved, notably the in vivo hepatic antioxidative responses to this neurotoxin. Aphantoxins extracted from a natural isolate of A. flos-aquae DC-1 were resolved by high performance liquid chromatography. The primary components were gonyautoxins 1 and 5 and neosaxitoxin...
March 2015: Ecotoxicology and Environmental Safety
De Lu Zhang, Jing Zhang, Chun Xiang Hu, Gao Hong Wang, Dun Hai Li, Yong Ding Liu
Aphanizomenon flos-aquae is a cyanobacterium that produces neurotoxins or paralytic shellfish poisons (PSPs) called aphantoxins, which present threats to environmental safety and human health via eutrophication of water bodies worldwide. Although the molecular mechanisms of this neurotoxin have been studied, many questions remain unsolved, including those relating to in vivo hepatic neurotransmitter inactivation, physiological detoxification and histological and ultrastructural alterations. Aphantoxins extracted from the natural strain of A...
December 2014: Aquatic Toxicology
Cheng Zou, Rui-Min Ye, Jian-Wei Zheng, Zhao-He Luo, Hai-Feng Gu, Wei-Dong Yang, Hong-Ye Li, Jie-Sheng Liu
To explore the genetic diversity and paralytic shellfish poisoning (PSP) toxin profile of the Alexandrium tamarense species complex along the coast of China, 67 strains of A. tamarense from the China Sea were collected and genetic diversity were analyzed based on the rDNA sequences. In addition, PSP toxin compositions and contents were detected by HPLC. According to the 5.8S rDNA and ITS, and LSU rDNA D1-D2 sequence, A. tamarense in the China Sea comprises at least Group IV and Group I ribotypes. In these Chinese strains, the toxins with the highest concentration in the profile were C1/2, gonyautoxins 1/4 (GTX1/4) and neosaxitoxin (NEO)...
December 15, 2014: Marine Pollution Bulletin
Eva Cagide, Paul G Becher, M Carmen Louzao, Begoña Espiña, Mercedes R Vieytes, Friedrich Jüttner, Luis M Botana
Hapalindoles make up a large group of bioactive metabolites of the cyanobacterial order Stigonematales. 12-epi-Hapalindole E isonitrile, 12-epi-hapalindole C isonitrile, 12-epi-hapalindole J isonitrile, and hapalindole L from Fischerella are acutely toxic for insect larvae; however, the biochemical targets responsible for the biological activities of hapalindoles are not understood. We describe here the electron impact mass spectra of these four hapalindole congeners; their structures were confirmed by nuclear magnetic resonance spectroscopy...
October 20, 2014: Chemical Research in Toxicology
Ramiro J Zepeda, Manila Candiracci, Nicolas Lobos, Sebastian Lux, Hugo F Miranda
Neosaxitoxin (NeoSTX) is a specific reversible blocker of voltage gated sodium channels on excitable cells. In the last decade, it has been tested in a number of interesting clinical trials, however there is still little information available on mammalian toxicity. Rats were treated for 12 weeks with doses of 1, 3 or 6 μg/kg of subcutaneous NeoSTX. At weeks 12 and 17, animals were sacrificed and blood samples collected for hematological and biochemical analysis. Organs were harvested for weight determination and histopathological assessments...
September 2014: Marine Drugs
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"