Next Issue
Volume 10, November
Previous Issue
Volume 10, September
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
7.5
3.9
Journals
Toxins
Volume 10
Issue 10
share announcement

Toxins, Volume 10, Issue 10 (October 2018) – 42 articles

Cover Story (view full-size image): Antivenom cross-reactivity has been investigated for decades to determine which antivenoms can be used to treat snakebite envenomings from different snake species. Besides the traditional methods for cross-reactivity investigations, such as enzymatic assays and in vivo neutralization studies, new methods, including antivenomics and high-density peptide microarray (HDPM) technology, have recently emerged. We provide an overview of both the classical and new methods used to explore antivenom cross-reactivity, the advantages and disadvantages of these methods, and examples of studies using the methods. A special focus is given to antivenomics and HDPM technology as these high-throughput methods may enable more detailed assessments of antivenom cross-reactivity. View this paper.
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
18 pages, 3925 KiB  
Review
Variations in the Botulinum Neurotoxin Binding Domain and the Potential for Novel Therapeutics
by Jonathan R. Davies, Sai Man Liu and K. Ravi Acharya
Toxins 2018, 10(10), 421; https://doi.org/10.3390/toxins10100421 - 20 Oct 2018
Cited by 24 | Viewed by 8397
Abstract
Botulinum neurotoxins (BoNTs) are categorised into immunologically distinct serotypes BoNT/A to /G). Each serotype can also be further divided into subtypes based on differences in amino acid sequence. BoNTs are ~150 kDa proteins comprised of three major functional domains: an N-terminal zinc metalloprotease [...] Read more.
Botulinum neurotoxins (BoNTs) are categorised into immunologically distinct serotypes BoNT/A to /G). Each serotype can also be further divided into subtypes based on differences in amino acid sequence. BoNTs are ~150 kDa proteins comprised of three major functional domains: an N-terminal zinc metalloprotease light chain (LC), a translocation domain (HN), and a binding domain (HC). The HC is responsible for targeting the BoNT to the neuronal cell membrane, and each serotype has evolved to bind via different mechanisms to different target receptors. Most structural characterisations to date have focussed on the first identified subtype within each serotype (e.g., BoNT/A1). Subtype differences within BoNT serotypes can affect intoxication, displaying different botulism symptoms in vivo, and less emphasis has been placed on investigating these variants. This review outlines the receptors for each BoNT serotype and describes the basis for the highly specific targeting of neuronal cell membranes. Understanding receptor binding is of vital importance, not only for the generation of novel therapeutics but also for understanding how best to protect from intoxication. Full article
(This article belongs to the Special Issue Bacterial Toxins: Structure–Function Relationship)
►▼ Show Figures

Figure 1

12 pages, 1309 KiB  
Article
Identification of Causative Ciguatoxins in Red Snappers Lutjanus bohar Implicated in Ciguatera Fish Poisonings in Vietnam
by Dao Viet Ha, Aya Uesugi, Hajime Uchida, Pham Xuan Ky, Dang Quoc Minh, Ryuichi Watanabe, Ryoji Matsushima, Hiroshi Oikawa, Satoshi Nagai, Mitsunori Iwataki, Yasuwo Fukuyo and Toshiyuki Suzuki
Toxins 2018, 10(10), 420; https://doi.org/10.3390/toxins10100420 - 20 Oct 2018
Cited by 24 | Viewed by 4387
Abstract
Ciguatera fish poisoning (CFP) is a type of food poisoning caused by the consumption of a variety of toxic ciguatera fish species in the tropical and subtropical waters. Although there have been a large number of suspected CFP cases in the Southeast Asian [...] Read more.
Ciguatera fish poisoning (CFP) is a type of food poisoning caused by the consumption of a variety of toxic ciguatera fish species in the tropical and subtropical waters. Although there have been a large number of suspected CFP cases in the Southeast Asian countries, few were confirmed with causative ciguatoxins (CTXs), and reliable information on the symptoms still remains rather limited. In the present study, CTXs in red snapper Lutjanus bohar, implicated in two suspected CFP cases in Vietnam in 2014 and 2016, were determined by use of the single-quadrupole selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS). Ciguatoxin-1B (CTX-1B), 54-deoxyCTX-1B, and 52-epi-54-deoxyCTX-1B were detected in the red snapper by our LC/MS method. Moreover, CTX-1B, 54-deoxyCTX-1B, and 52-epi-54-deoxyCTX-1B were further identified by the time of flight (TOF) LC/MS with the exact mass spectrum. The CTX profile of the red snapper in Vietnam is similar to those of ciguatera fish from Australia, Okinawa Islands in Japan, Kiribati, and Hong Kong. This is the first comprehensive report unambiguously identifying the causative toxins in fish implicated with reliable information on the poisoning symptoms in CFP in Vietnam and/or Southeast Asian countries. Full article
(This article belongs to the Special Issue Public Health Outreach to Prevention of Aquatic Toxin Exposure)
►▼ Show Figures

Figure 1

14 pages, 1827 KiB  
Article
Effects of a Fusarium Toxin-Contaminated Maize Treated with Sodium Sulfite on Male Piglets in the Presence of an LPS-Induced Acute Inflammation
by Anh-Tuan Tran, Jeannette Kluess, Andreas Berk, Marleen Paulick, Jana Frahm, Dian Schatzmayr, Susanne Kersten and Sven Dänicke
Toxins 2018, 10(10), 419; https://doi.org/10.3390/toxins10100419 - 18 Oct 2018
Cited by 5 | Viewed by 3234
Abstract
We investigated the effects of feeding sodium sulfite (SoS) treated uncontaminated and Fusarium contaminated maize in a porcine lipopolysaccharide (LPS) challenge model. Eighty piglets (7.59 ± 0.92 kg body weight [BW]) were equally assigned to one of four experimental diets containing 10% maize, [...] Read more.
We investigated the effects of feeding sodium sulfite (SoS) treated uncontaminated and Fusarium contaminated maize in a porcine lipopolysaccharide (LPS) challenge model. Eighty piglets (7.59 ± 0.92 kg body weight [BW]) were equally assigned to one of four experimental diets containing 10% maize, either uncontaminated and untreated (CON−, 0.09 mg deoxynivalenol [DON]/kg diet) or uncontaminated and SoS-treated (CON+, wet-preserved with 5 g SoS/kg maize; 0.05 mg DON/kg diet), or prepared with 10% of a Fusarium contaminated maize containing mainly deoxynivalenol (DON), either contaminated and untreated (FUS−, 5.36 mg DON/kg diet), or contaminated and SoS-treated (FUS+, wet-preserved with 5 g SoS/kg maize; 0.83 mg DON/kg diet). At day 42 of experiment, ten pigs of each group were injected intraperitoneally with either 7.5 µg LPS/kg BW or placebo (0.9% NaCl). At 120 min after injection, blood samples were collected to analyse TNF-α, hematological profile, clinical biochemistry as well as the redox status. A significant increase in body temperature and cytokine TNF-α concentration was observed in the LPS-injected piglets. Results for hematology, clinical chemistry and redox status indicate no effects of SoS treatment, with exception of neutrophil counts being significantly more pronounced after feeding the SoS treated FUS maize. In conclusion, SoS treatment of maize did not modulate the LPS-induced acute inflammation. Full article
(This article belongs to the Collection Fusarium Toxins – Relevance for Human and Animal Health)
►▼ Show Figures

Figure 1

14 pages, 1796 KiB  
Article
Spatial and Temporal Variability in the Development and Potential Toxicity of Phormidium Biofilms in the Tarn River, France
by Isidora Echenique-Subiabre, Maxime Tenon, Jean-François Humbert and Catherine Quiblier
Toxins 2018, 10(10), 418; https://doi.org/10.3390/toxins10100418 - 17 Oct 2018
Cited by 12 | Viewed by 3556
Abstract
Proliferation of Phormidium biofilms in rivers is becoming a worldwide sanitation problem for humans and animals, due to the ability of these bacteria to produce anatoxins. To better understand the environmental conditions that favor the development of Phormidium biofilms and the production of [...] Read more.
Proliferation of Phormidium biofilms in rivers is becoming a worldwide sanitation problem for humans and animals, due to the ability of these bacteria to produce anatoxins. To better understand the environmental conditions that favor the development of Phormidium biofilms and the production of anatoxins, we monitored the formation of these biofilms and their toxins for two years in the Tarn River, biofilms from which are known to have caused the deaths of multiple dogs. As previously observed in New Zealand, Phormidium biofilm development occurred in riffle areas. The coverage of these biofilms at the bottom of the river exhibited strong spatial and temporal variations, but was positively correlated with water temperature and depth. Anatoxin-a was detected in less than 50% of the biofilms. The concentrations of these toxins in the biofilms exhibited high spatiotemporal variability, with the highest concentrations being recorded at the end of the summer period at the upstream sampling sites. These findings suggest that the maturity of the biofilms, combined with the local environmental conditions, have an impact on the production of anatoxin, making risk assessment for these benthic proliferations challenging. Full article
(This article belongs to the Special Issue Potentially Toxic Benthic Microorganisms in Freshwater and Marine Ecosystems)
►▼ Show Figures

Graphical abstract

26 pages, 2806 KiB  
Article
RNA-Seq Analysis for Assessing the Early Response to DSP Toxins in Mytilus galloprovincialis Digestive Gland and Gill
by María Verónica Prego-Faraldo, Luisa Martínez and Josefina Méndez
Toxins 2018, 10(10), 417; https://doi.org/10.3390/toxins10100417 - 16 Oct 2018
Cited by 24 | Viewed by 4676
Abstract
The harmful effects of diarrhetic shellfish poisoning (DSP) toxins on mammalian cell lines have been widely assessed. Studies in bivalves suggest that mussels display a resistance to the cytogenotoxic effects of DSP toxins. Further, it seems that the bigger the exposure, the more [...] Read more.
The harmful effects of diarrhetic shellfish poisoning (DSP) toxins on mammalian cell lines have been widely assessed. Studies in bivalves suggest that mussels display a resistance to the cytogenotoxic effects of DSP toxins. Further, it seems that the bigger the exposure, the more resistant mussels become. To elucidate the early genetic response of mussels against these toxins, the digestive gland and the gill transcriptomes of Mytilus galloprovincialis after Prorocentrum lima exposure (100,000 cells/L, 48 h) were de novo assembled based on the sequencing of 8 cDNA libraries obtained using an Illumina HiSeq 2000 platform. The assembly provided 95,702 contigs. A total of 2286 and 4523 differentially expressed transcripts were obtained in the digestive gland and the gill, respectively, indicating tissue-specific transcriptome responses. These transcripts were annotated and functionally enriched, showing 44 and 60 significant Pfam families in the digestive gland and the gill, respectively. Quantitative PCR (qPCR) was performed to validate the differential expression patterns of several genes related to lipid and carbohydrate metabolism, energy production, genome integrity and defense, suggesting their participation in the protective mechanism. This work provides knowledge of the early response against DSP toxins in the mussel M. galloprovincialis and useful information for further research on the molecular mechanisms of the bivalve resistance to these toxins. Full article
(This article belongs to the Special Issue Dinophysis Toxins: Distribution, Fate in Shellfish and Impacts)
►▼ Show Figures

Graphical abstract

11 pages, 1077 KiB  
Article
Combining E-Nose and Lateral Flow Immunoassays (LFIAs) for Rapid Occurrence/Co-Occurrence Aflatoxin and Fumonisin Detection in Maize
by Matteo Ottoboni, Luciano Pinotti, Marco Tretola, Carlotta Giromini, Eleonora Fusi, Raffaella Rebucci, Maria Grillo, Luca Tassoni, Silvia Foresta, Silvia Gastaldello, Valentina Furlan, Claudio Maran, Vittorio Dell’Orto and Federica Cheli
Toxins 2018, 10(10), 416; https://doi.org/10.3390/toxins10100416 - 16 Oct 2018
Cited by 30 | Viewed by 3653
Abstract
The aim of this study was to evaluate the potential use of an e-nose in combination with lateral flow immunoassays for rapid aflatoxin and fumonisin occurrence/co-occurrence detection in maize samples. For this purpose, 161 samples of corn have been used. Below the regulatory [...] Read more.
The aim of this study was to evaluate the potential use of an e-nose in combination with lateral flow immunoassays for rapid aflatoxin and fumonisin occurrence/co-occurrence detection in maize samples. For this purpose, 161 samples of corn have been used. Below the regulatory limits, single-contaminated, and co-contaminated samples were classified according to the detection ranges established for commercial lateral flow immunoassays (LFIAs) for mycotoxin determination. Correspondence between methods was evaluated by discriminant function analysis (DFA) procedures using IBM SPSS Statistics 22. Stepwise variable selection was done to select the e-nose sensors for classifying samples by DFA. The overall leave-out-one cross-validated percentage of samples correctly classified by the eight-variate DFA model for aflatoxin was 81%. The overall leave-out-one cross-validated percentage of samples correctly classified by the seven-variate DFA model for fumonisin was 85%. The overall leave-out-one cross-validated percentage of samples correctly classified by the nine-variate DFA model for the three classes of contamination (below the regulatory limits, single-contaminated, co-contaminated) was 65%. Therefore, even though an exhaustive evaluation will require a larger dataset to perform a validation procedure, an electronic nose (e-nose) seems to be a promising rapid/screening method to detect contamination by aflatoxin, fumonisin, or both in maize kernel stocks. Full article
(This article belongs to the Collection Understanding Mycotoxin Occurrence in Food and Feed Chains)
►▼ Show Figures

Figure 1

13 pages, 2052 KiB  
Article
Antibody Microarray Immunoassay for Simultaneous Quantification of Multiple Mycotoxins in Corn Samples
by Xian Zhang, Zuohuan Wang, Yun Fang, Renjie Sun, Tong Cao, Narayan Paudyal, Weihuan Fang and Houhui Song
Toxins 2018, 10(10), 415; https://doi.org/10.3390/toxins10100415 - 15 Oct 2018
Cited by 20 | Viewed by 4362
Abstract
We developed and tested a prototype of an antibody microarray immunoassay for simultaneous quantitative detection of four typical mycotoxins (aflatoxin B1, ochratoxin A, zearalenone, and fumonisin B1) in corn samples. The test kit consisted of a nitrocellulose membrane layered [...] Read more.
We developed and tested a prototype of an antibody microarray immunoassay for simultaneous quantitative detection of four typical mycotoxins (aflatoxin B1, ochratoxin A, zearalenone, and fumonisin B1) in corn samples. The test kit consisted of a nitrocellulose membrane layered with immobilized monoclonal antibodies against mycotoxins. During the assay, the mycotoxin-protein conjugates were biotinylated. The signal detection was enhanced by a combination of the biotin-streptavidin system and enhanced chemiluminescence (ECL). This improved the sensitivity of the assay. Under the optimized conditions, four calibration curves with goodness of fit (R2 > 0.98) were plotted. The results showed that the detection limits for aflatoxin B1, ochratoxin A, zearalenone, and fumonisin B1 were 0.21, 0.19, 0.09, and 0.24 ng/mL, with detection ranges of 0.47–55.69, 0.48–127.11, 0.22–31.36, and 0.56–92.57 ng/mL, respectively. The limit of detection (LOD) of this antibody microarray for aflatoxin B1, ochratoxin A, zearalenone, and fumonisin B1 in corn was 5.25, 4.75, 2.25, and 6 μg/kg, respectively. The recovery rates from the spiked samples were between 79.2% and 113.4%, with coefficient of variation <10%. The results of the analysis of commercial samples for mycotoxins using this new assay and the liquid chromatography-tandem mass spectrometry (LC-MS/MS) were comparable and in good agreement. This assay could also be modified for the simultaneous detection of other multiple mycotoxins, as well as low-weight analytes, hazardous to human health. Full article
(This article belongs to the Collection Biorecognition Assays for Mycotoxins)
►▼ Show Figures

Figure 1

18 pages, 4620 KiB  
Article
Aggregatibacter actinomycetemcomitans Leukotoxin Is Delivered to Host Cells in an LFA-1-Indepdendent Manner When Associated with Outer Membrane Vesicles
by Justin B. Nice, Nataliya V. Balashova, Scott C. Kachlany, Evan Koufos, Eric Krueger, Edward T. Lally and Angela C. Brown
Toxins 2018, 10(10), 414; https://doi.org/10.3390/toxins10100414 - 13 Oct 2018
Cited by 40 | Viewed by 5625
Abstract
The Gram-negative bacterium, Aggregatibacter actinomycetemcomitans, has been associated with localized aggressive periodontitis (LAP). In particular, highly leukotoxic strains of A. actinomycetemcomitans have been more closely associated with this disease, suggesting that LtxA is a key virulence factor for A. actinomycetemcomitans. LtxA is [...] Read more.
The Gram-negative bacterium, Aggregatibacter actinomycetemcomitans, has been associated with localized aggressive periodontitis (LAP). In particular, highly leukotoxic strains of A. actinomycetemcomitans have been more closely associated with this disease, suggesting that LtxA is a key virulence factor for A. actinomycetemcomitans. LtxA is secreted across both the inner and outer membranes via the Type I secretion system, but has also been found to be enriched within outer membrane vesicles (OMVs), derived from the bacterial outer membrane. We have characterized the association of LtxA with OMVs produced by the highly leukotoxic strain, JP2, and investigated the interaction of these OMVs with host cells to understand how LtxA is delivered to host cells in this OMV-associated form. Our results demonstrated that a significant fraction of the secreted LtxA exists in an OMV-associated form. Furthermore, we have discovered that in this OMV-associated form, the toxin is trafficked to host cells by a cholesterol- and receptor-independent mechanism in contrast to the mechanism by which free LtxA is delivered. Because OMV-associated toxin is trafficked to host cells in an entirely different manner than free toxin, this study highlights the importance of studying both free and OMV-associated forms of LtxA to understand A. actinomycetemcomitans virulence. Full article
(This article belongs to the Special Issue Leukotoxins)
►▼ Show Figures

Figure 1

16 pages, 3784 KiB  
Article
Evaluating the Bioactivity of a Novel Broad-Spectrum Antimicrobial Peptide Brevinin-1GHa from the Frog Skin Secretion of Hylarana guentheri and Its Analogues
by Qi Chen, Peng Cheng, Chengbang Ma, Xinping Xi, Lei Wang, Mei Zhou, Huimin Bian and Tianbao Chen
Toxins 2018, 10(10), 413; https://doi.org/10.3390/toxins10100413 - 13 Oct 2018
Cited by 28 | Viewed by 4886
Abstract
Many antimicrobial peptides (AMPs) have been identified from the skin secretion of the frog Hylarana guentheri (H.guentheri), including Temporin, Brevinin-1, and Brevinin-2. In this study, an antimicrobial peptide named Brevinin-1GHa was identified for the first time by using ‘shotgun’ cloning. The [...] Read more.
Many antimicrobial peptides (AMPs) have been identified from the skin secretion of the frog Hylarana guentheri (H.guentheri), including Temporin, Brevinin-1, and Brevinin-2. In this study, an antimicrobial peptide named Brevinin-1GHa was identified for the first time by using ‘shotgun’ cloning. The primary structure was also confirmed through mass spectral analysis of the skin secretion purified by reversed-phase high-performance liquid chromatography (RP-HPLC). There was a Rana-box (CKISKKC) in the C-terminal of Brevinin-1GHa, which formed an intra-disulfide bridge. To detect the significance of Rana-box and reduce the hemolytic activity, we chemically synthesized Brevinin-1GHb (without Rana-box) and Brevinin-1GHc (Rana-box in central position). Brevinin-1GHa exhibited a strong and broad-spectrum antimicrobial activity against seven microorganisms, while Brevinin-1GHb only inhibited the growth of Staphylococcus aureus (S. aureus), which indicates Rana-box was necessary for the antimicrobial activity of Brevinin-1GHa. The results of Brevinin-1GHc suggested transferring Rana-box to the central position could reduce the hemolytic activity, but the antimicrobial activity also declined. Additionally, Brevinin-1GHa demonstrated the capability of permeating cell membrane and eliminating biofilm of S. aureus, Escherichia coli (E. coli), and Candida albicans (C. albicans). The discovery of this research may provide some novel insights into natural antimicrobial drug design. Full article
(This article belongs to the Special Issue Venom Peptides: Role of Predatory and Defensive Adaptations in Their Evolution and Chemical Biology)
►▼ Show Figures

Figure 1

11 pages, 499 KiB  
Review
Tryptophan-Derived Uremic Toxins and Thrombosis in Chronic Kidney Disease
by Tawfik Addi, Laetitia Dou and Stéphane Burtey
Toxins 2018, 10(10), 412; https://doi.org/10.3390/toxins10100412 - 12 Oct 2018
Cited by 68 | Viewed by 9741
Abstract
Patients with chronic kidney disease (CKD) display an elevated risk of thrombosis. Thrombosis occurs in cardiovascular events, such as venous thromboembolism, stroke, and acute coronary syndrome, and is a cause of hemodialysis vascular access dysfunction. CKD leads to the accumulation of uremic toxins, [...] Read more.
Patients with chronic kidney disease (CKD) display an elevated risk of thrombosis. Thrombosis occurs in cardiovascular events, such as venous thromboembolism, stroke, and acute coronary syndrome, and is a cause of hemodialysis vascular access dysfunction. CKD leads to the accumulation of uremic toxins, which exerts toxic effects on blood and the vessel wall. Some uremic toxins result from tryptophan metabolization in the gut through the indolic and the kynurenine pathways. An increasing number of studies are highlighting the link between such uremic toxins and thrombosis in CKD. In this review, we describe the thrombotic mechanisms induced by tryptophan-derived uremic toxins (TDUT). These mechanisms include an increase in plasma levels of procoagulant factors, induction of platelet hyperactivity, induction of endothelial dysfunction/ impairment of endothelial healing, decrease in nitric oxide (NO) bioavailability, and production of procoagulant microparticles. We focus on one important prothrombotic mechanism: The induction of tissue factor (TF), the initiator of the extrinsic pathway of the blood coagulation. This induction occurs via a new pathway, dependent on the transcription factor Aryl hydrocarbon receptor (AhR), the receptor of TDUT in cells. A better understanding of the prothrombotic mechanisms of uremic toxins could help to find novel therapeutic targets to prevent thrombosis in CKD. Full article
(This article belongs to the Special Issue Uremia and Cardiovascular Disease)
►▼ Show Figures

Figure 1

23 pages, 7174 KiB  
Article
Coagulotoxicity of Bothrops (Lancehead Pit-Vipers) Venoms from Brazil: Differential Biochemistry and Antivenom Efficacy Resulting from Prey-Driven Venom Variation
by Leijiane F. Sousa, Christina N. Zdenek, James S. Dobson, Bianca Op den Brouw, Francisco C. P. Coimbra, Amber Gillett, Tiago H. M. Del-Rei, Hipócrates De M. Chalkidis, Sávio Sant’Anna, Marisa M. Teixeira-da-Rocha, Kathleen Grego, Silvia R. Travaglia Cardoso, Ana M. Moura da Silva and Bryan G. Fry
Toxins 2018, 10(10), 411; https://doi.org/10.3390/toxins10100411 - 11 Oct 2018
Cited by 71 | Viewed by 8132
Abstract
Lancehead pit-vipers (Bothrops genus) are an extremely diverse and medically important group responsible for the greatest number of snakebite envenomations and deaths in South America. Bothrops atrox (common lancehead), responsible for majority of snakebites and related deaths within the Brazilian Amazon, is [...] Read more.
Lancehead pit-vipers (Bothrops genus) are an extremely diverse and medically important group responsible for the greatest number of snakebite envenomations and deaths in South America. Bothrops atrox (common lancehead), responsible for majority of snakebites and related deaths within the Brazilian Amazon, is a highly adaptable and widely distributed species, whose venom variability has been related to several factors, including geographical distribution and habitat type. This study examined venoms from four B. atrox populations (Belterra and Santarém, PA; Pres. Figueiredo, AM and São Bento, MA), and two additional Bothrops species (B. jararaca and B. neuwiedi) from Southeastern region for their coagulotoxic effects upon different plasmas (human, amphibian, and avian). The results revealed inter– and intraspecific variations in coagulotoxicity, including distinct activities between the three plasmas, with variations in the latter two linked to ecological niche occupied by the snakes. Also examined were the correlated biochemical mechanisms of venom action. Significant variation in the relative reliance upon the cofactors calcium and phospholipid were revealed, and the relative dependency did not significantly correlate with potency. Relative levels of Factor X or prothrombin activating toxins correlated with prey type and prey escape potential. The antivenom was shown to perform better in neutralising prothrombin activation activity than neutralising Factor X activation activity. Thus, the data reveal new information regarding the evolutionary selection pressures shaping snake venom evolution, while also having significant implications for the treatment of the envenomed patient. These results are, therefore, an intersection between evolutionary biology and clinical medicine. Full article
(This article belongs to the Special Issue Snakebite – From Science to Society. Selected papers)
►▼ Show Figures

Figure 1

15 pages, 5422 KiB  
Article
Urea Memory: Transient Cell Exposure to Urea Causes Persistent Mitochondrial ROS Production and Endothelial Dysfunction
by Maria D’Apolito, Anna Laura Colia, Enrica Manca, Massimo Pettoello-Mantovani, Michele Sacco, Angela Bruna Maffione, Michael Brownlee and Ida Giardino
Toxins 2018, 10(10), 410; https://doi.org/10.3390/toxins10100410 - 11 Oct 2018
Cited by 12 | Viewed by 3505
Abstract
Urea at post-dialysis levels induces increased ROS in a number of cell types. The aim of this study was to determine whether urea-induced production of ROS remains elevated after urea is no longer present, and, if it does, to characterize its origin and [...] Read more.
Urea at post-dialysis levels induces increased ROS in a number of cell types. The aim of this study was to determine whether urea-induced production of ROS remains elevated after urea is no longer present, and, if it does, to characterize its origin and effects. Human arterial endothelial cells were incubated with 20 mM urea for two days, and then cells were incubated for an additional two days in medium alone. Maximal ROS levels induced by initial urea continued at the same level despite urea being absent. These effects were prevented by either MnSOD expression or by Nox1/4 inhibition with GKT13781. Sustained urea-induced ROS caused a persistent reduction in mtDNA copy number and electron transport chain transcripts, a reduction in transcription of mitochondrial fusion proteins, an increase in mitochondrial fission proteins, and persistent expression of endothelial inflammatory markers. The SOD-catalase mimetic MnTBAP reversed each of these. These results suggest that persistent increases in ROS after cells are no long exposed to urea may play a major role in continued kidney damage and functional decline despite reduction of urea levels after dialysis. Full article
(This article belongs to the Special Issue Uremia and Cardiovascular Disease)
►▼ Show Figures

Figure 1

16 pages, 1181 KiB  
Article
Multiwalled Carbon Nanotube for One-Step Cleanup of 21 Mycotoxins in Corn and Wheat Prior to Ultraperformance Liquid Chromatography–Tandem Mass Spectrometry Analysis
by Dongmei Jiang, Dizhe Wei, Liuqing Wang, Shuai Ma, Yuanfang Du and Meng Wang
Toxins 2018, 10(10), 409; https://doi.org/10.3390/toxins10100409 - 10 Oct 2018
Cited by 26 | Viewed by 3623
Abstract
One-step solid-phase extraction (SPE) using a multiwalled carbon nanotube (MWCNT) for simultaneous analysis of 21 mycotoxins, including nine trichothecenes, zearalenone (ZEN) and its derivatives, four aflatoxins, and two ochratoxins, in corn and wheat was developed. Several key parameters affecting the performance of the [...] Read more.
One-step solid-phase extraction (SPE) using a multiwalled carbon nanotube (MWCNT) for simultaneous analysis of 21 mycotoxins, including nine trichothecenes, zearalenone (ZEN) and its derivatives, four aflatoxins, and two ochratoxins, in corn and wheat was developed. Several key parameters affecting the performance of the one-step SPE procedure—types of MWCNT, combinations with five sorbents (octadecylsilyl (C18), hydrophilic–lipophilic balance (HLB), mixed-mode cationic exchange (MCX), silica gel, and amino-propyl (NH2)), and filling amounts of the MWCNTs—were thoroughly investigated. The combination of 20 mg carboxylic MWCNT and 200 mg C18 was proven to be the most effective, allowing the quantification of all analyzed mycotoxins in corn and wheat. Under the optimized cleanup procedure prior to ultraperformance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) analysis, the method was validated by analyzing samples spiked at the limit of quantification (LOQ), two-times LOQ, and 10-times LOQ. Satisfactory linearity (r2 ≥ 0.9910), high sensitivity (LOQ in different ranges of 0.5–25 μg L−1), good recovery (75.6–110.3%), and acceptable precision (relative standard deviation (RSD), 0.3–10.7%) were obtained. The applicability of the method was further confirmed using raw samples of corn and wheat. In conclusion, the established method was rapid, simple and reliable for simultaneous analysis of 21 mycotoxins in corn and wheat. Full article
(This article belongs to the Special Issue Advanced Methods for Mycotoxins Detection)
►▼ Show Figures

Figure 1

15 pages, 5286 KiB  
Article
Purification and Characterization of JZTx-14, a Potent Antagonist of Mammalian and Prokaryotic Voltage-Gated Sodium Channels
by Jie Zhang, Dongfang Tang, Shuangyu Liu, Haoliang Hu, Songping Liang, Cheng Tang and Zhonghua Liu
Toxins 2018, 10(10), 408; https://doi.org/10.3390/toxins10100408 - 10 Oct 2018
Cited by 4 | Viewed by 3612
Abstract
Exploring the interaction of ligands with voltage-gated sodium channels (NaVs) has advanced our understanding of their pharmacology. Herein, we report the purification and characterization of a novel non-selective mammalian and bacterial NaVs toxin, JZTx-14, from the venom of the [...] Read more.
Exploring the interaction of ligands with voltage-gated sodium channels (NaVs) has advanced our understanding of their pharmacology. Herein, we report the purification and characterization of a novel non-selective mammalian and bacterial NaVs toxin, JZTx-14, from the venom of the spider Chilobrachys jingzhao. This toxin potently inhibited the peak currents of mammalian NaV1.2–1.8 channels and the bacterial NaChBac channel with low IC50 values (<1 µM), and it mainly inhibited the fast inactivation of the NaV1.9 channel. Analysis of NaV1.5/NaV1.9 chimeric channel showed that the NaV1.5 domain II S3–4 loop is involved in toxin association. Kinetics data obtained from studying toxin–NaV1.2 channel interaction showed that JZTx-14 was a gating modifier that possibly trapped the channel in resting state; however, it differed from site 4 toxin HNTx-III by irreversibly blocking NaV currents and showing state-independent binding with the channel. JZTx-14 might stably bind to a conserved toxin pocket deep within the NaV1.2–1.8 domain II voltage sensor regardless of channel conformation change, and its effect on NaVs requires the toxin to trap the S3–4 loop in its resting state. For the NaChBac channel, JZTx-14 positively shifted its conductance-voltage (G–V) and steady-state inactivation relationships. An alanine scan analysis of the NaChBac S3–4 loop revealed that the 108th phenylalanine (F108) was the key residue determining the JZTx-14–NaChBac interaction. In summary, this study provided JZTx-14 with potent but promiscuous inhibitory activity on both the ancestor bacterial NaVs and the highly evolved descendant mammalian NaVs, and it is a useful probe to understand the pharmacology of NaVs. Full article
(This article belongs to the Special Issue Toxins-Membrane Interactions)
►▼ Show Figures

Figure 1

17 pages, 3813 KiB  
Article
Protective Effect of N-Acetylcysteine against Oxidative Stress Induced by Zearalenone via Mitochondrial Apoptosis Pathway in SIEC02 Cells
by Jingjing Wang, Mengmeng Li, Wei Zhang, Aixin Gu, Jiawen Dong, Jianping Li and Anshan Shan
Toxins 2018, 10(10), 407; https://doi.org/10.3390/toxins10100407 - 9 Oct 2018
Cited by 42 | Viewed by 4660
Abstract
Zearalenone (ZEN), a nonsteroidal estrogen mycotoxin, is widely found in feed and foodstuffs. Intestinal cells may become the primary target of toxin attack after ingesting food containing ZEN. Porcine small intestinal epithelial (SIEC02) cells were selected to assess the effect of ZEN exposure [...] Read more.
Zearalenone (ZEN), a nonsteroidal estrogen mycotoxin, is widely found in feed and foodstuffs. Intestinal cells may become the primary target of toxin attack after ingesting food containing ZEN. Porcine small intestinal epithelial (SIEC02) cells were selected to assess the effect of ZEN exposure on the intestine. Cells were exposed to ZEN (20 µg/mL) or pretreated with (81, 162, and 324 µg/mL) N-acetylcysteine (NAC) prior to ZEN treatment. Results indicated that the activities of glutathione peroxidase (Gpx) and glutathione reductase (GR) were reduced by ZEN, which induced reactive oxygen species (ROS) and malondialdehyde (MDA) production. Moreover, these activities increased apoptosis and mitochondrial membrane potential (ΔΨm), and regulated the messenger RNA (mRNA) expression of Bax, Bcl-2, caspase-3, caspase-9, and cytochrome c (cyto c). Additionally, NAC pretreatment reduced the oxidative damage and inhibited the apoptosis induced by ZEN. It can be concluded that ZEN-induced oxidative stress and damage may further induce mitochondrial apoptosis, and pretreatment of NAC can degrade this damage to some extent. Full article
(This article belongs to the Special Issue Effects of Mycotoxins on the Intestine)
►▼ Show Figures

Figure 1

16 pages, 1709 KiB  
Article
New Method for Simultaneous Determination of Microcystins and Cylindrospermopsin in Vegetable Matrices by SPE-UPLC-MS/MS
by Leticia Díez-Quijada, Remedios Guzmán-Guillén, Ana I. Prieto Ortega, María Llana-Ruíz-Cabello, Alexandre Campos, Vítor Vasconcelos, Ángeles Jos and Ana M. Cameán
Toxins 2018, 10(10), 406; https://doi.org/10.3390/toxins10100406 - 8 Oct 2018
Cited by 40 | Viewed by 5059
Abstract
Cyanotoxins are a large group of noxious metabolites with different chemical structure and mechanisms of action, with a worldwide distribution, producing effects in animals, humans, and crop plants. When cyanotoxin-contaminated waters are used for the irrigation of edible vegetables, humans can be in [...] Read more.
Cyanotoxins are a large group of noxious metabolites with different chemical structure and mechanisms of action, with a worldwide distribution, producing effects in animals, humans, and crop plants. When cyanotoxin-contaminated waters are used for the irrigation of edible vegetables, humans can be in contact with these toxins through the food chain. In this work, a method for the simultaneous detection of Microcystin-LR (MC-LR), Microcystin-RR (MC-RR), Microcystin-YR (MC-YR), and Cylindrospermopsin (CYN) in lettuce has been optimized and validated, using a dual solid phase extraction (SPE) system for toxin extraction and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Results showed linear ranges (5–50 ng g−1 f.w.), low values for limit of detection (LOD) (0.06–0.42 ng g−1 f.w.), and limit of quantification (LOQ) (0.16–0.91 ng g−1 f.w.), acceptable recoveries (41–93%), and %RSDIP values for the four toxins. The method proved to be robust for the three variables tested. Finally, it was successfully applied to detect these cyanotoxins in edible vegetables exposed to cyanobacterial extracts under laboratory conditions, and it could be useful for monitoring these toxins in edible vegetables for better exposure estimation in terms of risk assessment. Full article
(This article belongs to the Special Issue Cyanobacteria and Cyanotoxins: New Advances and Future Challenges)
►▼ Show Figures

Figure 1

10 pages, 1414 KiB  
Article
Interaction of Clostridium perfringens Iota Toxin and Lipolysis-Stimulated Lipoprotein Receptor (LSR)
by Masahiro Nagahama, Masaya Takehara and Keiko Kobayashi
Toxins 2018, 10(10), 405; https://doi.org/10.3390/toxins10100405 - 8 Oct 2018
Cited by 13 | Viewed by 3772
Abstract
Iota toxin produced by Clostridium perfringens is a binary, actin ADP-ribosylating toxin that is organized into the enzymatically active component Ia and the binding component Ib. Lipolysis-stimulated lipoprotein receptor (LSR) has been identified as a cellular receptor of Ib. Here, we investigated the [...] Read more.
Iota toxin produced by Clostridium perfringens is a binary, actin ADP-ribosylating toxin that is organized into the enzymatically active component Ia and the binding component Ib. Lipolysis-stimulated lipoprotein receptor (LSR) has been identified as a cellular receptor of Ib. Here, we investigated the functional interaction between Ib and LSR, where siRNA for LSR blocked the toxin-mediated cytotoxicity and the binding of Ib. The addition of Ib to LSR-green fluorescence protein (GFP)-transfected cells at 4 °C resulted in colocalization with LSR and Ib on the cell surface. Upon transfer of the cells from 4 °C to 37 °C, LSR and Ib were internalized and observed in cytoplasmic vesicles. When the cells were incubated with Ib at 37 °C and fractionated using the Triton-insoluble membrane, Ib oligomer was localized in insoluble factions that fulfilled the criteria of lipid rafts, and LSR was clustered in lipid rafts. To examine the interaction between N-terminal extracellular region of LSR and Ib, we constructed a series of LSR N-terminal deletions. Ten amino acids residues can be deleted from this end without any reduction of Ib binding. However, deletion of 15 N-terminal residues drastically reduces its ability to bind Ib. These results demonstrate that Ib binds to the LSR N-terminal 10 to 15 residues and endocytoses into trafficking endosomes together with LSR. Full article
(This article belongs to the Special Issue ADP-Ribosylating Toxin)
►▼ Show Figures

Figure 1

22 pages, 4294 KiB  
Article
Uremia Impacts VE-Cadherin and ZO-1 Expression in Human Endothelial Cell-to-Cell Junctions
by Rayana A. P. Maciel, Regiane S. Cunha, Valentina Busato, Célia R. C. Franco, Paulo C. Gregório, Carla J. R. Dolenga, Lia S. Nakao, Ziad A. Massy, Agnès Boullier, Roberto Pecoits-Filho and Andréa E. M. Stinghen
Toxins 2018, 10(10), 404; https://doi.org/10.3390/toxins10100404 - 7 Oct 2018
Cited by 34 | Viewed by 5681
Abstract
Endothelial dysfunction in uremia can result in cell-to-cell junction loss and increased permeability, contributing to cardiovascular diseases (CVD) development. This study evaluated the impact of the uremic milieu on endothelial morphology and cell junction’s proteins. We evaluated (i) serum levels of inflammatory biomarkers [...] Read more.
Endothelial dysfunction in uremia can result in cell-to-cell junction loss and increased permeability, contributing to cardiovascular diseases (CVD) development. This study evaluated the impact of the uremic milieu on endothelial morphology and cell junction’s proteins. We evaluated (i) serum levels of inflammatory biomarkers in a cohort of chronic kidney disease (CKD) patients and the expression of VE-cadherin and Zonula Occludens-1 (ZO-1) junction proteins on endothelial cells (ECs) of arteries removed from CKD patients during renal transplant; (ii) ECs morphology in vitro under different uremic conditions, and (iii) the impact of uremic toxins p-cresyl sulfate (PCS), indoxyl sulfate (IS), and inorganic phosphate (Pi) as well as of total uremic serum on VE-cadherin and ZO-1 gene and protein expression in cultured ECs. We found that the uremic arteries had lost their intact and continuous endothelial morphology, with a reduction in VE-cadherin and ZO-1 expression. In cultured ECs, both VE-cadherin and ZO-1 protein expression decreased, mainly after exposure to Pi and uremic serum groups. VE-cadherin mRNA expression was reduced while ZO-1 was increased after exposure to PCS, IS, Pi, and uremic serum. Our findings show that uremia alters cell-to-cell junctions leading to an increased endothelial damage. This gives a new perspective regarding the pathophysiological role of uremia in intercellular junctions and opens new avenues to improve cardiovascular outcomes in CKD patients. Full article
(This article belongs to the Special Issue Uremia and Cardiovascular Disease)
►▼ Show Figures

Graphical abstract

12 pages, 269 KiB  
Article
Association of Uremic Toxins and Inflammatory Markers with Physical Performance in Dialysis Patients
by Maja Pajek, Alexander Jerman, Joško Osredkar, Jadranka Buturović Ponikvar and Jernej Pajek
Toxins 2018, 10(10), 403; https://doi.org/10.3390/toxins10100403 - 1 Oct 2018
Cited by 13 | Viewed by 3536
Abstract
Association of higher serum levels of uremic toxins and inflammatory markers with poorer physical performance is understudied. We measured the six-minute walk test (6MWT), 10 repetition sit-to-stand test (STS-10), handgrip strength (HGS), and Human Activity Profile (HAP) questionnaire score in 90 prevalent hemodialysis [...] Read more.
Association of higher serum levels of uremic toxins and inflammatory markers with poorer physical performance is understudied. We measured the six-minute walk test (6MWT), 10 repetition sit-to-stand test (STS-10), handgrip strength (HGS), and Human Activity Profile (HAP) questionnaire score in 90 prevalent hemodialysis patents, with low comorbidity to reduce the potential confounding of concomitant disease. Midweek pre-dialysis serum levels of asymmetric dimethyl-arginine (ADMA), β2-microglobulin (B2M), high-sensitivity C-reactive protein (hs-CRP), indoxyl sulfate (IS), insulin-like growth factor 1 (IGF-1), interleukin 6 (IL-6), myostatin, and urea were analyzed as predictor parameters of physical performance measures in adjusted models. Serum levels of most measured toxins were not significantly related to performance, except for ADMA, which was significantly related to poorer performance in the STS-10 test (B = 0.11 ± 0.03 s, p < 0.01). Higher hs-CRP was associated with poorer results in the 6MWT (B = −2.6 ± 0.97 m, p < 0.01) and a lower HAP score (B = −0.36 ± 0.14, p = 0.01). There were no other significant associations found. We conclude that inflammation may be a more important pathway to physical impediment than uremic toxemia. This suggests that there is a large physical rehabilitation potential in non-inflamed uremic patients. Full article
(This article belongs to the Special Issue Disposition of Uremic Toxins: The Challenges in Uremia)
12 pages, 1729 KiB  
Article
Extensive Contamination of Water with Saxitoxin Near the Dam of the Irkutsk Hydropower Station Reservoir (East Siberia, Russia)
by Mikhail Grachev, Ilya Zubkov, Irina Tikhonova, Maria Ivacheva, Anton Kuzmin, Elena Sukhanova, Ekaterina Sorokovikova, Galina Fedorova, Aleksandr Galkin, Maria Suslova, Olga Netsvetayeva, Elena Eletskaya, Tatyana Pogadaeva, Vladimir Smirnov, Andrey Ivanov, Vladimir Shagun, Viktor Minaev and Olga Belykh
Toxins 2018, 10(10), 402; https://doi.org/10.3390/toxins10100402 - 1 Oct 2018
Cited by 15 | Viewed by 4974
Abstract
An area of discolored water 50 m wide and 30 m long was found in September 2017 close to the dam of the Irkutsk hydroelectric power station. Water from this spot was sampled for investigation in the present study. Microscopic analysis revealed that [...] Read more.
An area of discolored water 50 m wide and 30 m long was found in September 2017 close to the dam of the Irkutsk hydroelectric power station. Water from this spot was sampled for investigation in the present study. Microscopic analysis revealed that the suspended matter in the sample was composed of clumps of filaments, vegetative cells, akinetes and heterocysts that formed short filaments and solitary cells. This matter was found to consist of partially degraded cells of the cyanobacterium Dolichospermum lemmermannii. Nucleotide sequencing of DNA isolated from the biomass revealed the presence of the sxtA gene which is involved in the synthesis of saxitoxin. Water from the polluted area contained 600 ± 100 μg L−1 saxitoxin as measured by HPLC-MS with pre-column modification of the toxin with 2,4-dinitrophenylhydrazine. Immunoassay analysis (ELISA) showed a concentration of saxitoxins in the water of 2900 ± 900 μg L−1. Hydrochemical and microbiological analyses suggested the contaminated area appeared as a result of a D. lemmermannii bloom, followed by its decay and release of saxitoxin and nutrients. The present paper describes the results of a case study. Better understanding of the phenomenon will depend on the possibility to perform implementation of a large-scale monitoring program. Full article
(This article belongs to the Section Marine and Freshwater Toxins)
►▼ Show Figures

Figure 1

8 pages, 746 KiB  
Article
Botulinum Toxin in Restless Legs Syndrome—A Randomized Double-Blind Placebo-Controlled Crossover Study
by Shivam Om Mittal, Duarte Machado, Diana Richardson, Divyanshu Dubey and Bahman Jabbari
Toxins 2018, 10(10), 401; https://doi.org/10.3390/toxins10100401 - 29 Sep 2018
Cited by 14 | Viewed by 5605
Abstract
Background: Restless Legs Syndrome (RLS) is a common movement disorder with an estimated prevalence of up to 12%. Previous small studies with onabotulinumtoxin A (OnaA) for RLS have shown inconsistent results. Methods: Twenty-four patients with an International RLS score (IRLS) of >11 (moderate-severe) [...] Read more.
Background: Restless Legs Syndrome (RLS) is a common movement disorder with an estimated prevalence of up to 12%. Previous small studies with onabotulinumtoxin A (OnaA) for RLS have shown inconsistent results. Methods: Twenty-four patients with an International RLS score (IRLS) of >11 (moderate-severe) were enrolled in this blinded, placebo-controlled crossover study. Twenty-one patients completed the evaluations at 4, 6, and 8 weeks after each injection. One-hundred units of Incobotulinumtoxin A (IncoA) or normal saline were injected into tibialis anterior, gastrocnemius, and biceps femoris muscles each side. Results: Improvement from a severe (IRLS >21) to a mild/moderate (IRLS ≤20) score was significant at four weeks (p = 0.0036) and six weeks (p = 0.0325) following IncoA administration compared to placebo. Additionally, there was significant improvement in pain score at six weeks as measured by Visual Analogue Scale (p = 0.04) and the Johns Hopkins Quality of Life Questionnaire (p = 0.01) in the IncoA group. Definite or marked improvement on Patient Global Impression of Change was seen in 7 out of 21 patients in the IncoA group vs. 1 out of 21 patients in the placebo group at 4 weeks (p = 0.012). Conclusion: IncoA injection lead to a reduction in severity of RLS symptoms, pain score, and quality of life, without any adverse effects. Full article
(This article belongs to the Special Issue Botulinum Toxin Treatment of Movement Disorders)
►▼ Show Figures

Figure 1

4 pages, 710 KiB  
Reply
Reply to Comment on Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures. Toxins 2018, 10, 18—Quintessential Use of Ultrasound Guidance for Botulinum Toxin Injections
by Katharine E. Alter and Barbara I. Karp
Toxins 2018, 10(10), 400; https://doi.org/10.3390/toxins10100400 - 28 Sep 2018
Cited by 2 | Viewed by 3355
Abstract
We thank the authors for their detailed letter and salient comments related to our article on Ultrasound Guidance for botulinum toxin (BoNT) injections.[...] Full article
(This article belongs to the Special Issue Muscle Selection for BoNT)
►▼ Show Figures

Figure 1

20 pages, 3951 KiB  
Article
Dinophysis acuta in Scottish Coastal Waters and Its Influence on Diarrhetic Shellfish Toxin Profiles
by Sarah C. Swan, Andrew D. Turner, Eileen Bresnan, Callum Whyte, Ruth F. Paterson, Sharon McNeill, Elaine Mitchell and Keith Davidson
Toxins 2018, 10(10), 399; https://doi.org/10.3390/toxins10100399 - 28 Sep 2018
Cited by 24 | Viewed by 4822
Abstract
Diarrhetic shellfish toxins produced by the dinoflagellate genus Dinophysis are a major problem for the shellfish industry worldwide. Separate species of the genus have been associated with the production of different analogues of the okadaic acid group of toxins. To evaluate the spatial [...] Read more.
Diarrhetic shellfish toxins produced by the dinoflagellate genus Dinophysis are a major problem for the shellfish industry worldwide. Separate species of the genus have been associated with the production of different analogues of the okadaic acid group of toxins. To evaluate the spatial and temporal variability of Dinophysis species and toxins in the important shellfish-harvesting region of the Scottish west coast, we analysed data collected from 1996 to 2017 in two contrasting locations: Loch Ewe and the Clyde Sea. Seasonal studies were also undertaken, in Loch Ewe in both 2001 and 2002, and in the Clyde in 2015. Dinophysis acuminata was present throughout the growing season during every year of the study, with blooms typically occurring between May and September at both locations. The appearance of D. acuta was interannually sporadic and, when present, was most abundant in the late summer and autumn. The Clyde field study in 2015 indicated the importance of a temperature front in the formation of a D. acuta bloom. A shift in toxin profiles of common mussels (Mytilus edulis) tested during regulatory monitoring was evident, with a proportional decrease in okadaic acid (OA) and dinophysistoxin-1 (DTX1) and an increase in dinophysistoxin-2 (DTX2) occurring when D. acuta became dominant. Routine enumeration of Dinophysis to species level could provide early warning of potential contamination of shellfish with DTX2 and thus determine the choice of the most suitable kit for effective end-product testing. Full article
(This article belongs to the Special Issue Dinophysis Toxins: Distribution, Fate in Shellfish and Impacts)
►▼ Show Figures

Graphical abstract

14 pages, 3807 KiB  
Article
The Effects of Autophagy and PI3K/AKT/m-TOR Signaling Pathway on the Cell-Cycle Arrest of Rats Primary Sertoli Cells Induced by Zearalenone
by Bing-jie Wang, Wang-long Zheng, Nan-nan Feng, Tao Wang, Hui Zou, Jian-hong Gu, Yan Yuan, Xue-zhong Liu, Zong-ping Liu and Jian-chun Bian
Toxins 2018, 10(10), 398; https://doi.org/10.3390/toxins10100398 - 28 Sep 2018
Cited by 60 | Viewed by 5568
Abstract
A high concentration of Zearalenone (ZEA) will perturb the differentiation of germ cells, and induce a death of germ cells, but the toxic mechanism and molecular mechanism remain unclear. The Sertoli cells (SCs) play an irreplaceable role in spermatogenesis. In order to explore [...] Read more.
A high concentration of Zearalenone (ZEA) will perturb the differentiation of germ cells, and induce a death of germ cells, but the toxic mechanism and molecular mechanism remain unclear. The Sertoli cells (SCs) play an irreplaceable role in spermatogenesis. In order to explore the potential mechanism of ZEA male reproductive toxicity, we studied the effects of ZEA on cell proliferation, cell-cycle distribution, cell-cycle-related proteins and autophagy-related pathway the PI3K/Akt/mTOR signaling in primary cultured rats SCs, and the effects of autophagy and PI3K/AKT/m TOR signaling pathway on the SCs cell-cycle arrest induced by ZEA treated with the autophagy promoter RAPA, autophagy inhibitor CQ, and the PI3K inhibitor LY294002, respectively. The data revealed that ZEA could inhibit the proliferation of SCs by arresting the cell cycle in the G2/M phase and trigger the autophagy via inhibiting the PI3K/Akt/m TOR signaling pathway. Promoting or inhibiting the level of autophagy could either augment or reverse the arrest of cell cycle. And it was regulated by PI3K/Akt/m TOR signaling pathway. Taken together, this study provides evidence that autophagy and PI3K/Akt/m TOR signaling pathway are involved in regulating rats primary SCs cell-cycle arrest due to ZEA in vitro. To some extent, ZEA-induced autophagy plays a protective role in this process. Full article
(This article belongs to the Section Mycotoxins)
►▼ Show Figures

Figure 1

20 pages, 6211 KiB  
Article
Interactions between Triterpenes and a P-I Type Snake Venom Metalloproteinase: Molecular Simulations and Experiments
by Lina María Preciado, Jaime Andrés Pereañez, Ettayapuram Ramaprasad Azhagiya Singam and Jeffrey Comer
Toxins 2018, 10(10), 397; https://doi.org/10.3390/toxins10100397 - 28 Sep 2018
Cited by 6 | Viewed by 4681
Abstract
Small molecule inhibitors of snake venom metalloproteinases (SVMPs) could provide a means to rapidly halt the progression of local tissue damage following viperid snake envenomations. In this study, we examine the ability of candidate compounds based on a pentacyclic triterpene skeleton to inhibit [...] Read more.
Small molecule inhibitors of snake venom metalloproteinases (SVMPs) could provide a means to rapidly halt the progression of local tissue damage following viperid snake envenomations. In this study, we examine the ability of candidate compounds based on a pentacyclic triterpene skeleton to inhibit SVMPs. We leverage molecular dynamics simulations to estimate the free energies of the candidate compounds for binding to BaP1, a P-I type SVMP, and compare these results with experimental assays of proteolytic activity inhibition in a homologous enzyme (Batx-I). Both simulation and experiment suggest that betulinic acid is the most active candidate, with the simulations predicting a standard binding free energy of Δ G ∘ = − 11.0 ± 1.4 kcal/mol. The simulations also reveal the atomic interactions that underlie binding between the triterpenic acids and BaP1, most notably the electrostatic interaction between carboxylate groups of the compounds and the zinc cofactor of BaP1. Together, our simulations and experiments suggest that occlusion of the S1 ′ subsite is essential for inhibition of proteolytic activity. While all active compounds make hydrophobic contacts in the S1 ′ site, β -boswellic acid, with its distinct carboxylate position, does not occlude the S1 ′ site in simulation and exhibits negligible activity in experiment. Full article
(This article belongs to the Special Issue Toxins and Bioinformatics)
►▼ Show Figures

Graphical abstract

3 pages, 936 KiB  
Comment
Comment on Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures. Toxins 2017, 10, 18—Quintessential Use of Ultrasound Guidance for Botulinum Toxin Injections—Muscle Innervation Zone Targeting Revisited
by Bayram Kaymak, Fevziye Ünsal Malas, Murat Kara, Arzu Yağız On and Levent Özçakar
Toxins 2018, 10(10), 396; https://doi.org/10.3390/toxins10100396 - 28 Sep 2018
Cited by 4 | Viewed by 3711
Abstract
Recently, the importance of targeting structures during botulinum neurotoxin applications has been discussed in a variety of disorders, including spasticity and dystonia. In this respect, the advantages of ultrasound imaging to traditional techniques have been emphasized. We would like underscore the importance of [...] Read more.
Recently, the importance of targeting structures during botulinum neurotoxin applications has been discussed in a variety of disorders, including spasticity and dystonia. In this respect, the advantages of ultrasound imaging to traditional techniques have been emphasized. We would like underscore the importance of ultrasound guidance, with targeting innervation zone(s) of the over-active muscles to achieve effective clinical outcomes. Additionally, we also clarify the difference between the terms—innervation zone (motor end plate) and motor point—which have been used by the authors as if they were the same. Further, we disagree with the authors about the intramuscular botulinum neurotoxin application techniques i.e., in-plane vs. out-of-plane whereby the former is, for sure, superior. Full article
(This article belongs to the Special Issue Muscle Selection for BoNT)
►▼ Show Figures

Figure 1

15 pages, 2062 KiB  
Article
Anatomical Distribution of Diarrhetic Shellfish Toxins (DSTs) in the Japanese Scallop Patinopecten yessoensis and Individual Variability in Scallops and Mytilus edulis Mussels: Statistical Considerations
by Ryoji Matsushima, Hajime Uchida, Ryuichi Watanabe, Hiroshi Oikawa, Izumi Oogida, Yuki Kosaka, Makoto Kanamori, Tatsuro Akamine and Toshiyuki Suzuki
Toxins 2018, 10(10), 395; https://doi.org/10.3390/toxins10100395 - 27 Sep 2018
Cited by 9 | Viewed by 3543
Abstract
Diarrhetic shellfish toxins (DSTs) are a group of phycotoxins that include okadaic acid (OA)/dinophysistoxin (DTX) analogues. At present, detailed data on the distribution of DST is insufficient, and studies of the appropriate sample sizes are lacking. This study investigated the DST frequency distribution [...] Read more.
Diarrhetic shellfish toxins (DSTs) are a group of phycotoxins that include okadaic acid (OA)/dinophysistoxin (DTX) analogues. At present, detailed data on the distribution of DST is insufficient, and studies of the appropriate sample sizes are lacking. This study investigated the DST frequency distribution in scallops and mussels by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and a resampling analysis of existing data was carried out. The DST population-interval and the necessary sample size were also estimated. DSTs are localized in the scallop digestive-gland, and the DST concentrations in scallops were water-depth-dependent. DST concentrations in scallops and mussels showed normal distributions, but mussels tended to contain more DSTs than scallops. In the statistical resampling analysis of the acquired data on scallops and mussels, especially that using the bootstrap method, sample size was difficult to estimate when the DST variation was large. Although the DST population-interval could be statistically estimated from the sample standard deviation of three samples, the sample size corresponded to the risk management level, and the use of 13 or more samples was preferable. The statistical methods used here to analyze individual contents and estimate population content-intervals could be applied in various situations and for shellfish toxins other than DSTs. Full article
(This article belongs to the Special Issue Dinophysis Toxins: Distribution, Fate in Shellfish and Impacts)
►▼ Show Figures

Figure 1

10 pages, 1145 KiB  
Article
Transitioning from Unilateral to Bilateral Upper Limb Tremor Therapy for Parkinson’s Disease and Essential Tremor Using Botulinum Toxin: Case Series
by Olivia Samotus, Jack Lee and Mandar Jog
Toxins 2018, 10(10), 394; https://doi.org/10.3390/toxins10100394 - 27 Sep 2018
Cited by 6 | Viewed by 3822
Abstract
Botulinum toxin type A (BoNT-A) injections guided by kinematic analysis for unilateral upper limb essential tremor (ET) and Parkinson’s disease (PD) tremor therapy has demonstrated efficacy, improvements in quality of life (QoL) and arm functionality. In this open-label pilot trial, 5 ET and [...] Read more.
Botulinum toxin type A (BoNT-A) injections guided by kinematic analysis for unilateral upper limb essential tremor (ET) and Parkinson’s disease (PD) tremor therapy has demonstrated efficacy, improvements in quality of life (QoL) and arm functionality. In this open-label pilot trial, 5 ET and 2 PD participants decided to switch from receiving long-term unilateral arm treatment to now bilateral BoNT-A arm therapy in their other tremulous arm which worsened over time. Injection patterns were based on kinematic analysis. Efficacy endpoints including kinematic analysis, Fahn-Tolosa-Marin tremor rating scale, QoL questionnaire, and maximal grip strength were collected over 2 treatments and 2 follow-up visits totaling 18-weeks. BoNT-A decreased wrist tremor amplitude by 84.6% and 89.6% 6-weeks following the 1st injection in the newly-treated limb in ET and PD participants, respectively. PD participants started with worse QoL but demonstrated an additional improvement in QoL by 29.9% for switching to bilateral treatment, whereas ET participants did not. Left and right arm tremor also did not share commonalities in severity or dose. This preliminary finding suggests trends for transitioning to bilateral therapy and warrants further studies to evaluate efficacy of bilateral tremor BoNT-A therapy in a larger cohort of PD and ET patients. Full article
(This article belongs to the Special Issue Botulinum Neurotoxins and Nervous System: Future Challenges for Novel Indications)
►▼ Show Figures

Figure 1

19 pages, 2427 KiB  
Review
Antibody Cross-Reactivity in Antivenom Research
by Line Ledsgaard, Timothy P. Jenkins, Kristian Davidsen, Kamille Elvstrøm Krause, Andrea Martos-Esteban, Mikael Engmark, Mikael Rørdam Andersen, Ole Lund and Andreas Hougaard Laustsen
Toxins 2018, 10(10), 393; https://doi.org/10.3390/toxins10100393 - 27 Sep 2018
Cited by 40 | Viewed by 8322
Abstract
Antivenom cross-reactivity has been investigated for decades to determine which antivenoms can be used to treat snakebite envenomings from different snake species. Traditionally, the methods used for analyzing cross-reactivity have been immunodiffusion, immunoblotting, enzyme-linked immunosorbent assay (ELISA), enzymatic assays, and in vivo neutralization [...] Read more.
Antivenom cross-reactivity has been investigated for decades to determine which antivenoms can be used to treat snakebite envenomings from different snake species. Traditionally, the methods used for analyzing cross-reactivity have been immunodiffusion, immunoblotting, enzyme-linked immunosorbent assay (ELISA), enzymatic assays, and in vivo neutralization studies. In recent years, new methods for determination of cross-reactivity have emerged, including surface plasmon resonance, antivenomics, and high-density peptide microarray technology. Antivenomics involves a top-down assessment of the toxin-binding capacities of antivenoms, whereas high-density peptide microarray technology may be harnessed to provide in-depth knowledge on which toxin epitopes are recognized by antivenoms. This review provides an overview of both the classical and new methods used to investigate antivenom cross-reactivity, the advantages and disadvantages of each method, and examples of studies using the methods. A special focus is given to antivenomics and high-density peptide microarray technology as these high-throughput methods have recently been introduced in this field and may enable more detailed assessments of antivenom cross-reactivity. Full article
(This article belongs to the Special Issue Discovery of Antibodies and Novel Antivenoms against Envenoming)
►▼ Show Figures

Figure 1

49 pages, 6096 KiB  
Article
Organic and Peptidyl Constituents of Snake Venoms: The Picture Is Vastly More Complex Than We Imagined
by Alejandro Villar-Briones and Steven D. Aird
Toxins 2018, 10(10), 392; https://doi.org/10.3390/toxins10100392 - 26 Sep 2018
Cited by 22 | Viewed by 7863
Abstract
Small metabolites and peptides in 17 snake venoms (Elapidae, Viperinae, and Crotalinae), were quantified using liquid chromatography-mass spectrometry. Each venom contains >900 metabolites and peptides. Many small organic compounds are present at levels that are probably significant in prey envenomation, given that their [...] Read more.
Small metabolites and peptides in 17 snake venoms (Elapidae, Viperinae, and Crotalinae), were quantified using liquid chromatography-mass spectrometry. Each venom contains >900 metabolites and peptides. Many small organic compounds are present at levels that are probably significant in prey envenomation, given that their known pharmacologies are consistent with snake envenomation strategies. Metabolites included purine nucleosides and their bases, neurotransmitters, neuromodulators, guanidino compounds, carboxylic acids, amines, mono- and disaccharides, and amino acids. Peptides of 2–15 amino acids are also present in significant quantities, particularly in crotaline and viperine venoms. Some constituents are specific to individual taxa, while others are broadly distributed. Some of the latter appear to support high anabolic activity in the gland, rather than having toxic functions. Overall, the most abundant organic metabolite was citric acid, owing to its predominance in viperine and crotaline venoms, where it chelates divalent cations to prevent venom degradation by venom metalloproteases and damage to glandular tissue by phospholipases. However, in terms of their concentrations in individual venoms, adenosine, adenine, were most abundant, owing to their high titers in Dendroaspis polylepis venom, although hypoxanthine, guanosine, inosine, and guanine all numbered among the 50 most abundant organic constituents. A purine not previously reported in venoms, ethyl adenosine carboxylate, was discovered in D. polylepis venom, where it probably contributes to the profound hypotension caused by this venom. Acetylcholine was present in significant quantities only in this highly excitotoxic venom, while 4-guanidinobutyric acid and 5-guanidino-2-oxopentanoic acid were present in all venoms. Full article
(This article belongs to the Section Animal Venoms)
►▼ Show Figures

Graphical abstract

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-42
Previous Issue
Next Issue
Back to TopTop