Fungal mycotoxin penisuloxazin A, a novel C-terminal Hsp90 inhibitor and characteristics of its analogues on Hsp90 function related to binding sites.

Hsp90 is a promising drug target for cancer therapy. However, toxicity and moderate effect are limitations of current inhibitors owing to broad protein degradation. The fungal mycotoxin penisuloxazin A (PNSA) belongs to a new epipolythiodiketopiperazines (ETPs) possessing a rare 3H-spiro[benzofuran-2,2'-piperazine] ring system. PNSA bound to cysteine residues C572/C598 of CT-Hsp90 with disulfide bonds and inhibits Hsp90 activity, resulting in apoptosis and growth inhibition of HCT116 cells in vitro and in vivo. We identified that analogues PEN-A and HDN-1 bound to C572/C597 and C572 of CT-Hsp90α respectively, with binding pattern very similar to PNSA. These ETPs exhibited different effects on ATPase activity, dimerization formation and selectivity on client protein of Hsp90, indicating client recognition of Hsp90 can be exactly regulated by different sites of Hsp90. Our findings not only offer new chemotypes for anticancer drug development, but also help to better understand biological function of Hsp90 for exploring inhibitor with some client protein bias.

The mechanism of Lactobacillus strains for their ability to remove fumonisins B1 and B2.

Two Lactobacillus strains, L. plantarum B7 and L. pentosus X8, exhibited high efficiency in removing fumonisins (FB1 and FB2) from aqueous medium. 52.9% FB1 and 85.2% FB2 were bound by L. plantarum B7, and 58.0% FB1 and 86.5% FB2 by L. pentosus X8, respectively. Temperature, incubation time, and pH affected the binding ability of two strains. Cell viability was not necessary for the binding ability. The various components of cell wall were determined for their ability to absorb FBS. The results revealed that the intact peptidoglycans exhibited the greatest capacity in binding FBs. Especially the better structural integrity of the peptidoglycans the more FBs was bound. Thus, the absorption of two bacterial cells to FBs is proposed to be a physical process, and peptidoglycans should be the main binding site. Additionally, Caco-2 cell lines were used to evaluate the ability of the two strains to reduce the damage of FBs in vitro. Caco-2 cell's death was reduced after the cell lines were subjected to both viable and non-viable L. pentosus X8, respectively. The two Lactobacillus strains might be used as a biological detoxification for the removal of FBs from diet and feed in the future.

Tetrodotoxin detection and species identification of pufferfish in retail roasted fish fillet by DNA barcoding in China.

This study identifies the pufferfish species and detects tetrodotoxin (TTX) in roasted fish fillet samples collected in Beijing, Qingdao and Xiamen, China. The cytochrome c oxidase I (COI) gene was used as the target gene for identification of the pufferfish species in the samples. Enzyme-linked immunosorbent assay (ELISA) screened the TTX levels in samples that had been detected as containing pufferfish by DNA barcode. A total of 125 samples were identified by DNA barcodes; 32 (26%) samples contained pufferfish composition and, among them, 26 (81%) were the highly toxic species Lagocephalus lunaris. All 32 samples containing the pufferfish composition were positive for TTX with levels ranging from 100 to 63,800 ng g(-1). Most of the 32 samples contained the highly toxic L. lunaris. Based on the results, we suggest that the monitoring of roasted fish fillet should be strengthened and the processing procedures should be standardised to minimise TTX poisoning caused by pufferfish.

Influence of prebiotics, probiotics and protein ingredients on mycotoxin bioaccessibility.

The aim of this study was to investigate the influence of prebiotic compounds (cellulose and inulin), food ingredients (milk whey, ß-lactoglobulin and calcium caseinate) and several probiotic microorganisms on the bioaccessibility of beauvericin (BEA), enniatins (ENs A, A1, B, B1), deoxynivalenol (DON) and zearalenone (ZEA) present in wheat crispy bread produced with wheat flour previously fermented with F. tricinctum, F. culmorum and G. zeae. The bioaccessibility of mycotoxins was determined by a dynamic simulated gastrointestinal digestion system, imitating the human digestive physiological conditions of the gastrointestinal tract. Mycotoxins were determined in the simulated intestinal fluids by liquid chromatography-tandem mass spectrometry (LC-MS/MS). EN bioaccessibility ranged from 15.1 to 30.6%, whereas the values evidenced for BEA ranged from 12 to 19%. DON showed bioaccessibility data ranging from 0.8 to 5.6% whereas for ZEA the data evidenced ranged from 26 to 44%. The bioaccessibility reduction evidenced using probiotic microorganisms for the mycotoxins studied ranged from 21 to 27.1% for ENs, from 29 to 39.7% for DON, from 41 to 57% for ZEA and from 6.6 to 10.5% for BEA. The addition of prebiotic and bioactive microorganisms decreased the bioaccessibility of mycotoxins, with a concentration-dependent behavior, thus being a potential strategy for reducing human exposure to these minor mycotoxins.

Cross-sectional validation of a quality of life questionnaire in spanish for patients allergic to hymenoptera venom

Introducción: En 2002 se desarrolló el primer cuestionario de calidad de vida para alérgicos a veneno de Vespula (VQLQ). El objetivo de este trabajo es desarrollar y validar una versión en español de este cuestionario. Métodos y Pacientes: Partiendo del VQLQ en inglés se realizó la traducción al español y adaptación cultural del cuestionario con una posterior retraducción consensuada con los autores de la versión original. Así se desarrolló el cuestionario de calidad de vida en español para pacientes alérgicos a veneno de himenópteros (HRQLHA). La validación transversal se realizó mediante un estudio multicéntrico, con diseño test-retest en el que se incluyeron pacientes mayores de 14 años con reacción sistémica por alergia a veneno de Apis, Vespula o Polistes . Se analizó la fiabilidad test-retest, la validez externa y la consistencia interna del cuestionario. Resultados: Se incluyeron 116 pacientes alérgicos a venenos de Apis, Vespula o Polistes . La puntuación media del HRQLHA fue 3.48. El estudio de fiabilidad test-retest mostró un coeficiente de correlación intraclase de 0.85. El HRQLHA mostró una correlación positiva (0.5) con el cuestionario de referencia externa, confirmando su validez. En el análisis de la consistencia interna se encontró una Alpha de Cronbach de 0.95 Conclusiones: El análisis estadístico muestra una elevada fiabilidad test-retest y consistencia interna del HRQLHA, además de su validez externa. En la validación del HRQLHA se han incluido por primera vez pacientes alérgicos a veneno de Polistes, muy prevalente en nuestra área, demostrando la utilidad del cuestionario también en estos pacientes (AU)

Introduction and Objectives: The first quality of life questionnaire for Vespula-allergic patients (Vespid Allergy Quality of Life Questionnaire [VQLQ]) was developed in 2002. Our objective was to perform the cross-sectional validation of the Spanish version of this questionnaire. Patients and Methods: Using the original English-language version of the VQLQ as a starting point, the Spanish translation and cultural adaptation were performed and the first Spanish version was backtranslated into English and discussed with the authors of the original version. The result was the Spanish Health-related Quality of Life Questionnaire for Hymenoptera Venom–Allergic Patients (HRQLHA). Cross-sectional validation was carried out in a multicenter study using a test-retest design. Patients over the age of 14 diagnosed with systemic allergic reaction to venom from Apis, Vespula, or Polistes species were included. The test-retest reliability, external validity, and internal consistency of the questionnaire were measured. Results: The sample comprised 116 patients. The mean HRQLHA score was 3.48. Test-retest reliability showed an intraclass correlation coefficient of 0.85. HRQLHA showed a positive correlation (0.5) with an external questionnaire, thus demonstrating its external validity. Analysis of the internal consistency of the HRQLHA yielded a Cronbach a of 0.95, which can be considered to be excellent. Conclusions: Statistical analysis revealed the high test-retest reliability, internal consistency, and external validity of the HRQLHA.The HRQLHA is the first validated questionnaire to include patients allergic to Polistes species, which is common in our area. Our findings show that the questionnaire is also valid for these patients (AU)

Fabrication of magnetic porous Fe-Mn binary oxide nanowires with superior capability for removal of As(III) from water.

Magnetic porous Fe-Mn binary oxide nanowires were successfully fabricated to efficient removal of As(III) from water. The adsorption capacity of the porous nanowires for As(III) obviously increased with increasing of manganese oxide in the composite, accompanying decrease of the saturation magnetization of the adsorbents. Magnetic porous Fe-Mn binary oxide nanowires with an initial Fe:Mn molar ratio of 1:3 exhibited the highest absorption capacity for As(III) and enable magnetic separation from water. The maximal adsorption capacity value is 171mgg(-1) at pH 7.0. In the initial pH range from 3 to 9, 200µgL(-1) of As(III) could be easily decreased to below 10µgL(-1) by the magnetic porous Fe-Mn binary oxide nanowires (0.05gL(-1)) within 75min, and the corresponding residual As was completely oxidized to less toxic As(V). The coexisting chloride, nitrate and sulfate had no significant effect on arsenic removal, whereas, phosphate and humic acid reduced the removal of As(III) by competing with arsenic species for adsorption sites. The resulting magnetic porous Fe-Mn binary oxide nanowires could be a promising adsorbent for As(III) removal from water.

From arrow poison to herbal medicine--the ethnobotanical, phytochemical and pharmacological significance of Cissampelos (Menispermaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Cissampelos species have a rich history of traditional use, being used for both therapeutic and toxic properties. It is traditionally applied therapeutically in a diverse range of conditions and diseases including asthma, cough, fever, arthritis, obesity, dysentery, snakebite, jaundice and heart, blood pressure and skin-related problems. Conversely, it was traditionally included in preparations of curare applied as arrow poison during hunting to cause death of animals by asphyxiation. This review unites the ethnobotanical knowledge on Cissampelos with the phytochemistry and pharmacological activity which has been explored thus far. In addition, it identifies knowledge gaps and suggests further research opportunities. METHODS: The available electronic literature on the genus Cissampelos was collected using database searches including Scopus, Google Scholar, Pubmed, Web of Science, etc. The searches were limited to peer-reviewed English journals with the exception of books and a few articles in foreign languages which were included. RESULTS: The literature revealed that pharmacological activity including analgesic and antipyretic, anti-inflammatory, anti-allergic, bronchodilator, immunomodulatory, memory-enhancing, antidepressant, neuroprotective, antimicrobial, antimalarial, antiparasitic, anti-ulcer, anticancer, anti-oxidant, cardiovascular, muscle-relaxant, hepatoprotective, antidiabetic, antidiarrhoeal, antifertility, and antivenom activity have been confirmed in vitro and/or in vivo for various Cissampelos species. Cissampelos pareira L. and Cissampelos sympodialis Eichl. are the most explored species of this genus and the smallest number of studies have been conducted on Cissampelos laxiflora Moldenke and Cissampelos tenuipes Engl. Many alkaloids isolated from Cissampelos such as warifteine, methylwarifteine, berberine, hayatin and hayatidin showed promising anti-allergic, immunosuppressive, antidepressant, anticancer, vasodilatory and muscle-relaxant activities. CONCLUSION: The plants of this genus are used in traditional medicine for the treatment of various ailments. These plants are a rich source of bioactive bisbenzylisoquinoline and aporphine alkaloids together with other minor constituents. Although these plants are reputable and revered in various traditional medicine systems, many have not yet been screened chemically or pharmacologically and so there is a vast amount of research still to be conducted to validate their traditional use.

Studies on pharmacological properties of mucus and sting venom ofPotamotrygon cf. henlei

Stingrays from the Potamotrygon cf. henlei species are widely distributed in high numbers throughout therivers of central-west Brazil, being the source of numerous envenomations occurring in the dry season, posinga serious public health problem even if not properly reported. The accidents usually involve fishermen andbathers, and to date there is no effective treatment for the injured. Considering these facts and limitations ofstudies aiming at understanding the effects induced by P. cf. henlei envenoming, this study aimed to describethe principal pharmacological and certain biochemical properties of the mucus and sting venom. We foundthat mucus and sting venom is toxic to mice having nociceptive, edematogenic and proteolysis activities. Ourresults also indicate that the inflammatory cellular influx observed could be triggered by the venom andmucus. Furthermore the venom and mucus were partially purified by solid-phase extraction tested forantimicrobial activity in which only the mucus presented activity. It could be inferred from the present studythat P. cf. henlei venom possesses a diverse mixture of peptides, enzymes and pharmacologically activecomponents.

Alternative bioassay for the detection of saxitoxin using the speckled cockroach (Nauphoeta cinerea).

Paralytic shellfish poisoning (PSP) toxins produced by cyanobacteria pose a risk to public health as they occur in drinking water reservoirs and recreational lakes and accumulate in the food chain. One of these PSP toxins, saxitoxin (STX) is one of the most toxic nonprotein substances known. Accordingly, there is a requirement to monitor for these toxins. The standard bioassay used to detect these toxins is the mouse bioassay; however, its use is constrained by animal ethics guidelines and practical considerations. Reported here is the use of the globally distributed speckled cockroach Nauphoeta cinerea as a bioassay test organism for the selective detection of PSP toxicity of Anabaena circinalis aqueous extract and STX. N. cinerea was shown to be tolerant to pure cylindrospermopsin (CYN) and microcystin-LR (MC-LR) at doses 10-fold greater than mouse LD50 values while being sensitive to STX. Similarly, N. cinerea was shown to be tolerant of toxin-containing aqueous extracts of Cylindrospermopsis raciborskii, Microcystis aeruginosa, and Nodularia spumigena while being sensitive to A. circinalis. Peak sensitivity to STX was 60 min postinjection with a KD50 of 31.2 ng/g body weight. While this was approximately 3-fold less sensitive than the mouse bioassay, the insect test organism was around 34-fold smaller in mass than a mouse (20 g); thus one-tenth the amount of toxin in absolute quantity was required to reach an ED50 level. The N. cinerea bioassay presents a selective test for PSP toxicity that is rapid, economical, efficient, and simple to perform.

Perspectives of liquid chromatography coupled to low- and high-resolution mass spectrometry for screening, identification, and quantification of drugs in clinical and forensic toxicology.

This article reviews papers on the use of liquid chromatography coupled to low- and high-resolution mass spectrometry in clinical and forensic toxicology. They cover procedures for target and for more comprehensive screening for drugs (of abuse), identification of drug metabolites, and multianalyte procedures for quantification of drugs and/or their metabolites in body samples. Besides a critical overview, perspectives are discussed.

Prymnesins: toxic metabolites of the golden alga, Prymnesium parvum Carter (Haptophyta).

Increasingly over the past century, seasonal fish kills associated with toxic blooms of Prymnesium parvum have devastated aquaculture and native fish, shellfish, and mollusk populations worldwide. Protracted blooms of P. parvum can result in major disturbances to the local ecology and extensive monetary losses. Toxicity of this alga is attributed to a collection of compounds known as prymnesins, which exhibit potent cytotoxic, hemolytic, neurotoxic and ichthyotoxic effects. These secondary metabolites are especially damaging to gill-breathing organisms and they are believed to interact directly with plasma membranes, compromising integrity by permitting ion leakage. Several factors appear to function in the activation and potency of prymnesins including salinity, pH, ion availability, and growth phase. Prymnesins may function as defense compounds to prevent herbivory and some investigations suggest that they have allelopathic roles. Since the last extensive review was published, two prymnesins have been chemically characterized and ongoing investigations are aimed at the purification and analysis of numerous other toxic metabolites from this alga. More information is needed to unravel the mechanisms of prymnesin synthesis and the significance of these metabolites. Such work should greatly improve our limited understanding of the physiology and biochemistry of P. parvum and how to mitigate its blooms.

Antigenic cross-reactivity and immunogenicity of Bothrops venomsfrom snakes of the Amazon region

Snakebites are still a critical public health problem in developing countries or isolated areas. In Brazil, the North Region has a high distribution coefficient worsened by the significant number of eventually unreported cases, due to difficulties in access to healthservices, to the natural geographic barriers and the vast territory. In the Rio Negro area, the species Bothrops atrox, Bothrops brazili, Lachesis muta muta and Bothriopsis taeniata arethought to be the major species responsible for snakebites. The aim of this study was to qualitatively and quantitatively determine the antigenic cross-reactivity and expression oftoxins and the immunogenicity of Bothrops venom species of the Amazon and to evaluate the general efficacy of the therapeutic sera. The in vivo assays demonstrated that the defibrinating activity of B. taeniata venom was absent but that the lethal and hemorrhagic properties were more intense than in the B. atrox venom. The results evidence venom variability among the two B. atrox populations from two distinct Amazonian regions, which may reveal a subjacent speciation process. The results point to new aspects that mayguide the improvement of anti-Bothropic therapeutic serum.

Solid-phase extraction clean-up of ciguatoxin-contaminated coral fish extracts for use in the mouse bioassay.

Florisil solid-phase extraction (SPE) cartridges were used for purifying ciguatoxin (CTX)-contaminated coral fish extracts, with the aim of removing extracted lipid but retaining optimal level of CTXs in the purified fractions. The CTX-containing fraction (target fraction) in fish ether extract was isolated and purified by eluting through a commercially available Florisil cartridge with hexane-acetone-methanol solvent mixtures of increasing polarity (hexane-acetone (4:1, v/v) < acetone-methanol (7:3, v/v) < 100% methanol). Application of Florisil SPE using acetone-methanol (7:3, v/v) condition facilitated the separation of 4.2 +/- 0.4 mg (mean +/- standard error of the mean (SEM)) of purified target fraction from 20 mg ether extract with good retention of CTXs. The mouse bioassay was used to demonstrate that the average CTX recovery of the target fraction from CTX-spiked samples was 75.8% +/- 3.3%, which was significantly increased by 96.7% +/- 15% when compared with CTX recovery from ether extracts (44.8% +/- 5.2%) without performing SPE purification. Over 70% of non-target lipids were removed in which no CTX toxicity was found. Moreover, the target fractions of both CTX-spiked and naturally CTX-contaminated samples gave more prominent toxic responses of hypothermia and/or induced more rapid death of the mice. The use of acetone-methanol (7:3, v/v) condition in the elution could significantly improve overall recovery of CTXs, while minimizing the possible interferences of lipid matrix from co-extractants on mice.

Aflatoxin B1 contamination in wheat grain samples collected from different geographical regions of India: A multicenter study.

In a multicenter study conducted by the Indian Council of Medical Research, 1,646 samples of wheat grain collected from rural and urban areas of 10 states representing different geographical regions of India were analyzed for aflatoxin B1 (AFB1). AFB1 concentrations of > or = 5 microg kg(-1) were recorded in 40.3% of the samples, and concentrations above the Indian permissible regulatory limit of 30 microg kg(-1) were found in 16% of the samples. The proportion of samples with AFB1 concentrations above the Indian regulatory limit ranged from 1.7 to 55.8% in different states, with the minimum in Haryana and the maximum in Orissa. The variation in wheat contamination among states seems to be mainly the result of unsatisfactory storage conditions. Median AFB1 concentrations of 11, 18, and 32 microg kg(-1) were observed in samples from Uttar Pradesh, Assam, and Orissa, respectively; concentrations in other states were <5 microg kg(-1). The maximum AFB1 concentration of 606 microg kg(-1) was observed in a sample from the state of Uttar Pradesh. The calculated probable daily intakes of AFB1 through consumption of contaminated wheat for the population in some states were much higher than the suggested provisional maximum tolerable daily intake. Human health hazards associated with such AFB1 exposure over time cannot be ruled out.

Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics.

With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of extracts of arthropods and microsympatric Malagasy poison frogs (Mantella) collected from Ranomafana, Madagascar. Arthropod sources for 11 "poison frog" alkaloids were discovered, 7 of which were also detected in microsympatric Mantella. These arthropod sources include three endemic Malagasy ants, Tetramorium electrum, Anochetus grandidieri, and Paratrechina amblyops (subfamilies Myrmicinae, Ponerinae, and Formicinae, respectively), and the pantropical tramp millipede R. purpureus. Two of these ant species, A. grandidieri and T. electrum, were also found in Mantella stomachs, and ants represented the dominant prey type (67.3% of 609 identified stomach arthropods). To our knowledge, detection of 5,8-disubstituted (ds) indolizidine iso-217B in T. electrum represents the first izidine having a branch point in its carbon skeleton to be identified from ants, and detection of 3,5-ds pyrrolizidine 251O in A. grandidieri represents the first ponerine ant proposed as a dietary source of poison frog alkaloids. Endemic Malagasy ants with defensive alkaloids (with the exception of Paratrechina) are not closely related to any Neotropical species sharing similar chemical defenses. Our results suggest convergent evolution for the acquisition of defensive alkaloids in these dietary ants, which may have been the critical prerequisite for subsequent convergence in poison frogs between Madagascar and the Neotropics.