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1.
Birth Defects Res ; 116(1): e2284, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38158745

ABSTRACT

INTRODUCTION: Seven gadolinium-based contrast agents (GBCAs), four linear and three macrocyclic, were evaluated for potential effects on development, including behavior of juvenile CD-1 mice. METHODS: The GBCAs were administered via intravenous injection once daily on postnatal day (PND) 9, 12, 15, 18, and 21 (PND 1 was the day of delivery) at doses up to twice the human equivalent clinical dose (i.e., 0.63 mmol Gd/kg for gadoxetate disodium and 2.5 mmol Gd/kg for the other GBCAs). Mice were bled for evaluation of exposure (plasma) to gadolinium (Gd) on PND 9, 12, and 70. At scheduled euthanasia, the liver, spleen, brain, skin (dorsal surface), bone (left femur), and kidneys were excised from up to six mice/sex/group on PND 10, 22, or 70 for the determination of Gd levels and histopathological analysis. All mice were monitored for toxicity, growth and survival, sexual maturation, and behavior. CONCLUSION: Gd was quantifiable in the brain tissues with levels declining over time. There was no long-term effect on the growth and development for mice exposed to any of the GBCAs. There was no impact on neurodevelopment as assessed by brain histology and validated neurobehavioral tests, including a functional observational battery, motor activity, and learning and memory as evaluated in the Morris water maze. For all GBCAs, the highest dose tested represented the no-observable-adverse-effect level in juvenile mice.


Subject(s)
Contrast Media , Organometallic Compounds , Mice , Humans , Animals , Contrast Media/pharmacology , Gadolinium/pharmacology , Organometallic Compounds/pharmacology , Magnetic Resonance Imaging , Brain
2.
Int J Mol Sci ; 24(14)2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37511474

ABSTRACT

Perfluorinated and polyfluorinated alkyl substances (PFAS), more than 4700 in number, are a group of widely used man-made chemicals that accumulate in living things and the environment over time. They are known as "forever chemicals" because they are extremely persistent in our environment and body. Because PFAS have been widely used for many decades, their presence is evident globally, and their persistence and potential toxicity create concern for animals, humans and environmental health. They can have multiple adverse health effects, such as liver damage, thyroid disease, obesity, fertility problems, and cancer. The most significant source of living exposure to PFAS is dietary intake (food and water), but given massive industrial and domestic use, these substances are now punctually present not only domestically but also in the outdoor environment. For example, livestock and wildlife can be exposed to PFAS through contaminated water, soil, substrate, air, or food. In this review, we have analyzed and exposed the characteristics of PFAS and their various uses and reported data on their presence in the environment, from industrialized to less populated areas. In several areas of the planet, even in areas far from large population centers, the presence of PFAS was confirmed, both in marine and terrestrial animals (organisms). Among the most common PFAS identified are undoubtedly perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), two of the most widely used and, to date, among the most studied in terms of toxicokinetics and toxicodynamics. The objective of this review is to provide insights into the toxic potential of PFAS, their exposure, and related mechanisms.


Subject(s)
Alkanesulfonic Acids , Fluorocarbons , Animals , Humans , Alkanesulfonic Acids/toxicity , Water Pollution , Fluorocarbons/toxicity , Water
3.
Toxins (Basel) ; 15(6)2023 06 02.
Article in English | MEDLINE | ID: mdl-37368675

ABSTRACT

Pimelea is a genus of about 140 plant species, some of which are well-known for causing animal poisoning resulting in significant economic losses to the Australian livestock industry. The main poisonous species/subspecies include Pimelea simplex (subsp. simplex and subsp. continua), P. trichostachya and P. elongata (generally referred to as Pimelea). These plants contain a diterpenoid orthoester toxin, called simplexin. Pimelea poisoning is known to cause the death of cattle (Bos taurus and B. indicus) or weaken surviving animals. Pimelea species are well-adapted native plants, and their diaspores (single seeded fruits) possess variable degrees of dormancy. Hence, the diaspores do not generally germinate in the same recruitment event, which makes management difficult, necessitating the development of integrated management strategies based on infestation circumstances (e.g., size and density). For example, the integration of herbicides with physical control techniques, competitive pasture establishment and tactical grazing could be effective in some situations. However, such options have not been widely adopted at the field level to mitigate ongoing management challenges. This systematic review provides a valuable synthesis of the current knowledge on the biology, ecology, and management of poisonous Pimelea species with a focus on the Australian livestock industry while identifying potential avenues for future research.


Subject(s)
Diterpenes , Plant Poisoning , Thymelaeaceae , Animals , Cattle , Plants, Toxic , Australia , Livestock , Plant Poisoning/veterinary
4.
Sci Total Environ ; 894: 164744, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37315601

ABSTRACT

Boron (B) is released to terrestrial and aquatic environments through both natural and anthropogenic sources. This review describes the current knowledge on B contamination in soil and aquatic environments in relation to its geogenic and anthropogenic sources, biogeochemistry, environmental and human health impacts, remediation approaches, and regulatory practices. The common naturally occurring sources of B include borosilicate minerals, volcanic eruptions, geothermal and groundwater streams, and marine water. Boron is extensively used to manufacture fiberglass, thermal-resistant borosilicate glass and porcelain, cleaning detergents, vitreous enamels, weedicides, fertilizers, and B-based steel for nuclear shields. Anthropogenic sources of B released into the environment include wastewater for irrigation, B fertilizer application, and waste from mining and processing industries. Boron is an essential element for plant nutrition and is taken up mainly as boric acid molecules. Although B deficiency in agricultural soils has been observed, B toxicity can inhibit plant growth in soils under arid and semiarid regions. High B intake by humans can be detrimental to the stomach, liver, kidneys and brain, and eventually results in death. Amelioration of soils and water sources enriched with B can be achieved by immobilization, leaching, adsorption, phytoremediation, reverse osmosis, and nanofiltration. The development of cost-effective technologies for B removal from B-rich irrigation water including electrodialysis and electrocoagulation techniques is likely to help control the predominant anthropogenic input of B to the soil. Future research initiatives for the sustainable remediation of B contamination using advanced technologies in soil and water environments are also recommended.


Subject(s)
Boron , Minerals , Humans , Boron/toxicity , Risk Management , Soil , Water
5.
Front Microbiol ; 14: 1085818, 2023.
Article in English | MEDLINE | ID: mdl-37125184

ABSTRACT

The gradual spread of Aspergilli worldwide is adding to the global shortage of food and is affecting its safe consumption. Aspergillus-derived mycotoxins, including aflatoxins and ochratoxin A, and fumonisins (members of the fusariotoxin group) can cause pathological damage to vital organs, including the kidney or liver. Although the kidney functions as the major excretory system in mammals, monitoring and screening for mycotoxin induced nephrotoxicity is only now a developmental area in the field of livestock feed toxicology. Currently the assessment of individual exposure to mycotoxins in man and animals is usually based on the analysis of toxin and/or metabolite contamination in the blood or urine. However, this requires selective and sensitive analytical methods (e.g., HPLC-MS/MS), which are time consuming and expensive. The toxicokinetic of mycotoxin metabolites is becoming better understood. Several kidney biomarkers are used successfully in drug development, however cost-efficient, and reliable kidney biomarkers are urgently needed for monitoring farm animals for early signs of kidney disease. ß2-microglobulin (ß2-MG) and N-acetyl-ß-D-glucosaminidase (NAG) are the dominant biomarkers employed routinely in environmental toxicology research, while kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) are also emerging as effective markers to identify mycotoxin induced nephropathy. Pigs are exposed to mycotoxins due to their cereal-based diet and are particularly susceptible to Aspergillus mycotoxins. In addition to commonly used diagnostic markers for nephrotoxicity including plasma creatinine, NAG, KIM-1 and NGAL can be used in pigs. In this review, the currently available techniques are summarized, which are used for screening mycotoxin induced nephrotoxicity in farm animals. Possible approaches are considered, which could be used to detect mycotoxin induced nephropathy.

6.
Birth Defects Res ; 115(7): 782-796, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36916488

ABSTRACT

BACKGROUND: Olaratumab (Lartruvo™) is a recombinant human IgG1 monoclonal antibody that specifically binds PDGFRα. In order to support use of Lartruvo in pediatric patients, a definitive juvenile animal study in neonatal mice was conducted with a human anti-mouse PDGFRα antibody analog of olaratumab (LSN3338786). METHODS: A pilot study was used to set doses for the definitive juvenile mouse study. In the definitive study, juvenile mice were administered vehicle, 50, 100, or 150 mg/kg LSN3338786 by subcutaneous (SC) injection every 3 days between postnatal days (PND) 1 and 49, for a total of 17 doses. Blood samples were collected on PND 49 for antibody analysis and toxicokinetic evaluation. Tissues were collected on PND 52 for histopathologic examination. RESULTS: Results of the pilot study indicated that dosing neonatal mice starting on PND 1 via SC administration every 3 days was logistically feasible, produced exposures consistent with prior animal studies, and the selected dose levels were well tolerated by juvenile mice. In the definitive juvenile study, there were no LSN3338786-related deaths, clinical findings, and no effects on mean body weights, body weight gains, or food consumption. Additionally, there were no adverse LSN3338786-related hematology findings, and no macroscopic, organ weight, or microscopic findings of note. The highest dose evaluated, 150 mg/kg, was considered the NOAEL for juvenile toxicity. CONCLUSIONS: In conclusion, the juvenile animal studies did not identify any new toxicities or increased sensitivities for the intended pediatric patient population. The use of the surrogate antibody approach in a standard rodent model enabled the de-risking of theoretical concerns for toxicity in pediatric patients due to disruption of the PDGFRα pathway during early human development, such as pulmonary development.


Subject(s)
Antibodies, Monoclonal , Receptor, Platelet-Derived Growth Factor alpha , Animals , Mice , Humans , Child , Pilot Projects , Antibodies, Monoclonal/adverse effects , No-Observed-Adverse-Effect Level
7.
Environ Pollut ; 320: 121077, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36646409

ABSTRACT

Beryllium (Be) is a relatively rare element and occurs naturally in the Earth's crust, in coal, and in various minerals. Beryllium is used as an alloy with other metals in aerospace, electronics and mechanical industries. The major emission sources to the atmosphere are the combustion of coal and fossil fuels and the incineration of municipal solid waste. In soils and natural waters, the majority of Be is sorbed to soil particles and sediments. The majority of contamination occurs through atmospheric deposition of Be on aboveground plant parts. Beryllium and its compounds are toxic to humans and are grouped as carcinogens. The general public is exposed to Be through inhalation of air and the consumption of Be-contaminated food and drinking water. Immobilization of Be in soil and groundwater using organic and inorganic amendments reduces the bioavailability and mobility of Be, thereby limiting the transfer into the food chain. Mobilization of Be in soil using chelating agents facilitates their removal through soil washing and plant uptake. This review provides an overview of the current understanding of the sources, geochemistry, health hazards, remediation practices, and current regulatory mandates of Be contamination in complex environmental settings, including soil and aquatic ecosystems.


Subject(s)
Beryllium , Soil Pollutants , Humans , Ecosystem , Soil , Soil Pollutants/analysis , Risk Management , Coal
8.
Arch Toxicol ; 96(8): 2261-2285, 2022 08.
Article in English | MEDLINE | ID: mdl-35695909

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) have been widely used and represent a class of environmental persistent chemicals. An association of a reduction of vaccination efficacy with PFAS serum levels in humans was used by the European Food Safety Authority as a key effect for PFAS risk assessment. The data support for using this association is reviewed by a critical analysis of the respective human epidemiology and the available animal studies on the immunomodulation of PFAS. Based on an analysis of the available human epidemiology, the overall level of evidence regarding associations between PFAS serum levels and reduced antibody response remains weak. Absence of an association between an increase in clinical infections and PFAS serum levels and the limited understanding of the importance of antibody levels as an isolated data point further support this conclusion. Animal toxicity studies with PFAS focusing on immunomodulation also provide only limited support for immunomodulation as an important endpoint in PFAS toxicity. While immunomodulation is observed after PFAS administration, generally at blood concentrations several orders of magnitude above those seen in environmentally exposed humans, the relevance of these observation is hampered by the high doses required to influence immune endpoints, the limited number of endpoints assessed, and inconsistent results. The limitations of the current database on associations of human PFAS exposures outlined here indicate that more evidence is required to select immunomodulation as a critical endpoint for human PFAS risk assessment.


Subject(s)
Alkanesulfonic Acids , Environmental Pollutants , Fluorocarbons , Animals , Fluorocarbons/chemistry , Fluorocarbons/toxicity , Humans , Immunomodulation
9.
Toxicol Ind Health ; 38(9): 578-594, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35148210

ABSTRACT

Animal toxicity studies on diisocyanates were evaluated using quantitative weight of evidence (QWoE) to test the hypothesis that the dose-response curve shows a threshold for the induction and/or elicitation of respiratory sensitization. A literature search identified 59 references that included at least two concentration groups of the diisocyanate and a vehicle-exposed concurrent control in the study design. These studies were subjected to a QWoE-assessment applying scoring criteria for quality and relevance/strength of effects relevant to the selected endpoint of respiratory sensitization. Overall, the studies assessing dose/concentration-response for diisocyanates with the endpoint, respiratory sensitization, were heterogenous regarding study design, animal models used, endpoints assessed, and quality. Only a limited number of the studies subjected to the QWoE-assessment allowed drawing conclusions about possible thresholds for respiratory sensitization. Highest quality and relevance/strength of effects scores were obtained by a series of studies specifically designed to investigate a potential threshold for elicitation of respiratory sensitization in the Brown Norway (BN) rat. These studies applied an elaborate study design to optimize induction of respiratory sensitization and reduce interference by respiratory tract irritation. In summary, the available studies provided moderate to good support for the existence of a threshold for elicitation and limited to moderate support for a threshold regarding induction of respiratory allergy by diisocyanates in experimental animals. However, a quantitative extrapolation of threshold values established in rodents to humans remains complex.


Subject(s)
Respiratory Hypersensitivity , Allergens , Animals , Humans , Isocyanates/toxicity , Rats , Respiratory Hypersensitivity/chemically induced
10.
Angew Chem Int Ed Engl ; 59(38): 16747-16754, 2020 09 14.
Article in English | MEDLINE | ID: mdl-32524717

ABSTRACT

The exceptional nature of WO3-x dots has inspired widespread interest, but it is still a significant challenge to synthesize high-quality WO3-x dots without using unstable reactants, expensive equipment, and complex synthetic processes. Herein, the synthesis of ligand-free WO3-x dots is reported that are highly dispersible and rich in oxygen vacancies by a simple but straightforward exfoliation of bulk WS2 and a mild follow-up chemical conversion. Surprisingly, the WO3-x dots emerged as co-reactants for the electrochemiluminescence (ECL) of Ru(bpy)32+ with a comparable ECL efficiency to the well-known Ru(bpy)32+ /tripropylamine (TPrA) system. Moreover, compared to TPrA, whose toxicity remains a critical issue of concern, the WO3-x dots were ca. 300-fold less toxic. The potency of WO3-x dots was further explored in the detection of circulating tumor cells (CTCs) with the most competitive limit of detection so far.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Luminescent Measurements , Neoplastic Cells, Circulating/pathology , Organometallic Compounds/chemistry , Oxides/chemistry , Propylamines/chemistry , Tungsten/chemistry , Humans , Oxides/chemical synthesis
11.
Toxicol Pathol ; 48(4): 549-559, 2020 06.
Article in English | MEDLINE | ID: mdl-32347786

ABSTRACT

The Society of Toxicologic Pathology (STP) explored current institutional practices for selecting between non-blinded versus blinded histopathologic evaluation during Good Laboratory Practice (GLP)-compliant, regulatory-type animal toxicity studies using a multi-question survey and STP-wide discussion (held at the 2019 STP annual meeting). Survey responses were received from 107 individuals representing 83 institutions that collectively employ 589 toxicologic pathologists. Most responses came from industry (N = 46, mainly biopharmaceutical or contract research organizations) and consultants (N = 24). For GLP-compliant animal toxicity studies, histopathologic evaluation usually involves initial (primary) non-blinded analysis, with post hoc informal blinded re-examination at the study pathologist's discretion to confirm subtle findings or establish thresholds. Initial blinded histopathologic evaluation sometimes is chosen by study pathologists to test formal hypotheses and/or by sponsors to address non-pathologist expectations about histopathology data objectivity. Current practice is that a blinded histopathologic evaluation is documented only if formal blinding (ie, using slides with coded labels) is employed, using simple statements without detailed methodology in the study protocol (or an amendment) and/or pathology report. Blinding is not an appropriate strategy for the initial histopathologic evaluation performed during pathology peer reviews of GLP-compliant animal toxicity studies. [Box: see text].


Subject(s)
Toxicity Tests/methods , Animals , Animals, Laboratory , Humans , Pathologists , Pathology/methods , Peer Review , Research Design , Surveys and Questionnaires , Toxicology/methods
12.
Toxicol Rep ; 5: 750-758, 2018.
Article in English | MEDLINE | ID: mdl-29984188

ABSTRACT

The present study was taken up to evaluate the single dose acute toxicity, 28 days and 90 days repeated dose toxicity and reproductive/developmental toxicity of standardized 40% Garcinol in experimental rodents. The studies were conducted in compliance with OECD principles of good laboratory practice, guidelines for testing of chemicals no.420, 407, 408 and 421 respectively. Single dose acute oral toxicity was conducted on female Wistar rats as sighting study step-I (300 mg/kg) & sighting study step-II (2000 mg/kg) and main study (2000 mg/kg). Sub-acute, sub-chronic and reproductive/developmental studies were conducted in Wistar rats divided equally in vehicle control, 20, 50 and 100 mg/kg dose group along with recovery groups for vehicle control and high dose. Reproductive/developmental study was carried out for minimum of 28 days and in females during pregnancy and 4 days post partum. There were no abnormal clinical signs/behavioural changes, reproductive and developmental parameters, gross and histopathological changes as well as no alteration in the body weight, body temperature, haematology and other biochemical parameters in all the four studies. 40% Garcinol has a low toxicity profile in rodents and had no observed effects under experimental conditions used.

13.
J Anim Ecol ; 87(4): 1192-1204, 2018 07.
Article in English | MEDLINE | ID: mdl-29476541

ABSTRACT

Classical research on animal toxicity has focused on the role of toxins in protection against predators, but recent studies suggest these same compounds can offer a powerful defense against parasites and infectious diseases. Newts in the genus Taricha are brightly coloured and contain the potent neurotoxin, tetrodotoxin (TTX), which is hypothesized to have evolved as a defense against vertebrate predators such as garter snakes. However, newt populations often vary dramatically in toxicity, which is only partially explained by predation pressure. The primary aim of this study was to evaluate the relationships between TTX concentration and infection by parasites. By systematically assessing micro- and macroparasite infections among 345 adult newts (sympatric populations of Taricha granulosa and T. torosa), we detected 18 unique taxa of helminths, fungi, viruses and protozoans. For both newt species, per-host concentrations of TTX, which varied from undetectable to >60 µg/cm2 skin, negatively predicted overall parasite richness as well as the likelihood of infection by the chytrid fungus, Batrachochytrium dendrobatidis, and ranavirus. No such effect was found on infection load among infected hosts. Despite commonly occurring at the same wetlands, T. torosa supported higher parasite richness and average infection load than T. granulosa. Host body size and sex (females > males) tended to positively predict infection levels in both species. For hosts in which we quantified leucocyte profiles, total white blood cell count correlated positively with both parasite richness and total infection load. By coupling data on host toxicity and infection by a broad range of micro- and macroparasites, these results suggest that-alongside its effects on predators-tetrodotoxin may help protect newts against parasitic infections, highlighting the importance of integrative research on animal chemistry, immunological defenses and natural enemy ecology.


Subject(s)
Host-Parasite Interactions , Mycoses/veterinary , Phenotype , Salamandridae , Tetrodotoxin/metabolism , Animals , Biodiversity , California/epidemiology , Chytridiomycota/isolation & purification , Female , Male , Microbiota , Mycoses/epidemiology , Mycoses/microbiology , Mycoses/parasitology , Parasite Load/veterinary , Parasites/isolation & purification , Salamandridae/genetics
14.
Biotechnol Prog ; 34(1): 218-230, 2018 01.
Article in English | MEDLINE | ID: mdl-28960911

ABSTRACT

Copper oxide nanoparticles (CUNPs) were synthesized using Olea europaea leaf extract as reducing and protecting agent. The formation of nanoparticles was observed through a color change from yellowish to brownish black. The CUNPs were confirmed with UV-Vis spectrophotometer, which revealed a peak absorbance at 289 nm. The synthesized CUNPs were characterized by XRD, FTIR, SEM, and TEM. The XRD pattern revealed that CUNPs were crystalline in nature with a diameter around 20 nm. FTIR spectral analysis showed that CUNPs were capped with plant constituents. From SEM and TEM analyses, the CUNPs were generally found to be spherical in shape, and the size range was 20-50 nm. Free radical scavenging potential of CUNPs against DPPH was confirmed by its stable antioxidant effects. In addition, the toxicity of CUNPs in mice was also assessed by body weight and weights of liver, kidneys, spleen, and thymus. The immune response in mice was signaled through an obvious change in spleen and thymus index, with a decrease of ADA enzyme activity in serum, spleen, and thymus after CUNPs treatment. The CUNPs were found to exert cell growth arrest against AMJ-13 and SKOV-3 cancer cells in a dose-dependent manner and induce cell death by apoptosis. Less significant cytotoxic effect was observed in normal dermal fibroblast cells. These findings suggest that CUNPs may have the potential to be anticancer agents. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:218-230, 2018.


Subject(s)
Copper/chemistry , Metal Nanoparticles/chemistry , Olea/chemistry , Plant Extracts/chemistry , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Fibroblasts/drug effects , Free Radical Scavengers/chemistry , Green Chemistry Technology , Humans , Mice , Plant Extracts/chemical synthesis , Plant Extracts/pharmacology , Plant Leaves/chemistry , Spectroscopy, Fourier Transform Infrared
15.
Toxicon ; 137: 120-127, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28755852

ABSTRACT

The dermal glands of many amphibian species secrete toxins or other noxious substances as a defense strategy against natural enemies. Newts in particular possess the potent neurotoxin tetrodotoxin (TTX), for which the highest concentrations are found in species within the genus Taricha. Adult Taricha are hypothesized to use TTX as a chemical defense against vertebrate predators such as garter snakes (Thamnophis spp.). However, less is known about how TTX functions to defend aquatic-developing newt larvae against natural enemies, including trematode parasites and aquatic macroinvertebrates. Here we experimentally investigated the effects of exogenous TTX exposure on survivorship of the infectious stages (cercariae) of five species of trematode parasites that infect larval amphibians. Specifically, we used dose-response curves to test the sensitivity of trematode cercariae to progressively increasing concentrations of TTX (0.0 [control], 0.63, 3.13, 6.26, 31.32, and 62.64 nmol L-1) and how this differed among parasite species. We further compared these results to the effects of TTX exposure (0 and 1000 nmolL-1) over 24 h on seven macroinvertebrate taxa commonly found in aquatic habitats with newt larvae. TTX significantly reduced the survivorship of trematode cercariae for all species, but the magnitude of such effects varied among species. Ribeiroia ondatrae - which causes mortality and limb malformations in amphibians - was the least sensitive to TTX, whereas the kidney-encysting Echinostoma trivolvis was the most sensitive. Among the macroinvertebrate taxa, only mayflies (Ephemeroptera) showed a significant increase in mortality following exogenous TTX exposure, despite the use of a concentration 16x higher than the maximum used for trematodes. Our results suggest that maternal investment of TTX into larval newts may provide protection against certain trematode infections and highlight the importance of future work assessing the effects of newt toxicity on both parasite infection success and the palatability of larval newts to invertebrate predators.


Subject(s)
Insecta/drug effects , Tetrodotoxin/pharmacology , Trematoda/drug effects , Animals , Larva/drug effects , Larva/parasitology , Predatory Behavior/physiology , Salamandridae/growth & development , Salamandridae/parasitology
16.
Risk Anal ; 37(11): 2107-2118, 2017 11.
Article in English | MEDLINE | ID: mdl-28555874

ABSTRACT

Quantitative risk assessment often begins with an estimate of the exposure or dose associated with a particular risk level from which exposure levels posing low risk to populations can be extrapolated. For continuous exposures, this value, the benchmark dose, is often defined by a specified increase (or decrease) from the median or mean response at no exposure. This method of calculating the benchmark dose does not take into account the response distribution and, consequently, cannot be interpreted based upon probability statements of the target population. We investigate quantile regression as an alternative to the use of the median or mean regression. By defining the dose-response quantile relationship and an impairment threshold, we specify a benchmark dose as the dose associated with a specified probability that the population will have a response equal to or more extreme than the specified impairment threshold. In addition, in an effort to minimize model uncertainty, we use Bayesian monotonic semiparametric regression to define the exposure-response quantile relationship, which gives the model flexibility to estimate the quantal dose-response function. We describe this methodology and apply it to both epidemiology and toxicology data.

17.
Int J Nanomedicine ; 11: 3621-40, 2016.
Article in English | MEDLINE | ID: mdl-27536103

ABSTRACT

Rosmarinic acid (RA) possesses several protective bioactivities that have attracted increasing interest by nutraceutical/pharmaceutical industries. Considering the reduced bioavailability after oral use, effective (and safe) delivery systems are crucial to protect RA from gastrointestinal degradation. This study aims to characterize the safety profile of solid lipid nanoparticles produced with Witepsol and Carnauba waxes and loaded with RA, using in vitro and in vivo approaches, focused on genotoxicity and cytotoxicity assays, redox status markers, hematological and biochemical profile, liver and kidney function, gut bacterial microbiota, and fecal fatty acids composition. Free RA and sage extract, empty nanoparticles, or nanoparticles loaded with RA or sage extract (0.15 and 1.5 mg/mL) were evaluated for cell (lymphocytes) viability, necrosis and apoptosis, and antioxidant/prooxidant effects upon DNA. Wistar rats were orally treated for 14 days with vehicle (control) and with Witepsol or Carnauba nanoparticles loaded with RA at 1 and 10 mg/kg body weight/d. Blood, urine, feces, and several tissues were collected for analysis. Free and loaded RA, at 0.15 mg/mL, presented a safe profile, while genotoxic potential was found for the higher dose (1.5 mg/mL), mainly by necrosis. Our data suggest that both types of nanoparticles are safe when loaded with moderate concentrations of RA, without in vitro genotoxicity and cytotoxicity and with an in vivo safety profile in rats orally treated, thus opening new avenues for use in nutraceutical applications.


Subject(s)
Cinnamates/administration & dosage , Cinnamates/pharmacology , Depsides/administration & dosage , Depsides/pharmacology , Lipids/chemistry , Nanoparticles/chemistry , Administration, Oral , Animals , Cell Survival/drug effects , Cinnamates/adverse effects , Cytokinesis/drug effects , DNA/metabolism , Depsides/adverse effects , Gastrointestinal Microbiome/drug effects , Lipids/toxicity , Lymphocytes/drug effects , Male , Nanoparticles/toxicity , Nanoparticles/ultrastructure , Oxidation-Reduction , Rats, Wistar , Real-Time Polymerase Chain Reaction , Triglycerides/chemistry , Waxes/chemistry , Rosmarinic Acid
18.
Regul Toxicol Pharmacol ; 72(3): 572-7, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26056066

ABSTRACT

Many approved medicines are used with their adverse drug reactions (ADRs) appropriately managed in the clinical setting based on their risks and benefits. In this survey, the correlation between human ADR (specifically syncope/loss of consciousness and seizures/convulsions) and safety signals reported in animal studies has been investigated for 393 Japanese medicines which were approved between September 1999 and March 2013. Clinically important drug-induced ADR, syncope/loss of consciousness and seizures/convulsions are reported in this paper. Of 393 medicines, 101 (25.7%) showed syncope/loss of consciousness and 105 (26.7%) showed seizures/convulsions. Syncope/loss of consciousness and seizures/convulsions were reported for many medicines affecting the central nervous system. The animal toxicity concordance ratio with syncope/loss of consciousness and seizures/convulsions was 4.0% (4/101) and 23.8% (25/105), respectively. The underlying cases of syncope/loss of consciousness attributed to hypotension, arrhythmia, hypoglycemia or acute toxic reaction was 16.8%, 5.0%, 4.0% or 4.0%, respectively. Mechanism of seizures/convulsions for the remaining 101 medicines was not identified except for four local anesthetics. This survey suggested that the careful attention to and understanding of medicine profiles is necessary for the appropriate use of recently approved medicines in Japan.


Subject(s)
Drug-Related Side Effects and Adverse Reactions/epidemiology , Seizures/chemically induced , Syncope/chemically induced , Unconsciousness/chemically induced , Animals , Drug Approval , Humans , Japan/epidemiology , Seizures/epidemiology , Syncope/epidemiology , Unconsciousness/epidemiology
19.
Asian Pac J Trop Biomed ; 4(8): 614-7, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25183330

ABSTRACT

OBJECTIVE: To determine lethal median dose (LD50) and histopathological toxicity of water extract of Holothuria atra (H. atra) in mice. METHODS: The behavioral changes, mortality and histopathology examination on liver were assessed in mice 14 d after the administration (i.p.) of H. atra water extract. Seven doses (10, 20, 30, 50, 100, 150 and 200 mg/kg) of H. atra were used. The control group was treated with normal saline. RESULTS: In the acute study in mice, the water extracts of H. atra caused dose-dependent general behavior adverse affects and mortality. The main behavioral sign of toxicity was hypoactivity, noticed immediately after administration of the extract which was more obvious at the higher doses and persisted until death. Mortality increased with increasing doses, the calculated LD50 was 41 mg/kg in mice. The liver toxicity was confirmed by histopathological examination, which indicated the presence of abnormal hepatocytes with a distorted shape and undefined cell lining as well as enlarged nuclei in low doses groups. High doses groups indicated a more prominent distortion of the polyhedral hepatocytes with undefined cell lining, massive cytoplasm, pyknotic, karyorhexis and karyolytic nuclei (necrosis of hepatocytes). Control group showed polyhedral hepatocytes with defined cell lining arranged in cords and normal round nuclei, with granular cytoplasm. CONCLUSIONS: Because of the relatively low LD50 value in the acute study in mice, it may be concluded that the H. atra water extract is toxic.

20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-672929

ABSTRACT

Objective:To determine lethal median dose (LD50) and histopathological toxicity of water extract of Holothuria atra (H. atra) in mice. Methods: The behavioral changes, mortality and histopathology examination on liver were assessed in mice 14 d after the administration (i.p.) of H. atra water extract. Seven doses (10, 20, 30, 50, 100, 150 and 200 mg/kg) of H. atra were used. The control group was treated with normal saline. Results:In the acute study in mice, the water extracts of H. atra caused dose-dependent general behavior adverse affects and mortality. The main behavioral sign of toxicity was hypoactivity, noticed immediately after administration of the extract which was more obvious at the higher doses and persisted until death. Mortality increased with increasing doses, the calculated LD50 was 41 mg/kg in mice. The liver toxicity was confirmed by histopathological examination, which indicated the presence of abnormal hepatocytes with a distorted shape and undefined cell lining as well as enlarged nuclei in low doses groups. High doses groups indicated a more prominent distortion of the polyhedral hepatocytes with undefined cell lining, massive cytoplasm, pyknotic, karyorhexis and karyolytic nuclei (necrosis of hepatocytes). Control group showed polyhedral hepatocytes with defined cell lining arranged in cords and normal round nuclei, with granular cytoplasm. Conclusions: Because of the relatively low LD50 value in the acute study in mice, it may be concluded that the H. atra water extract is toxic.

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