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1.
ScientificWorldJournal ; 2024: 8991384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957454

RESUMO

The medicinal plant Bredemeyera floribunda Willd. is used to treat cardiovascular disease, chronic fatigue, low libido, as well as increased diuresis. However, studies considering the toxicity of this plant are scarce. Develop an aqueous extract of B. floribunda considering traditional use and determine the average lethality (LD50), signs, and symptoms of toxicity. The B. floribunda extract was obtained by immersing the root bark in ultrapure water for 18 hours at 4°C, under constant stirring. The test extract was administered in a single dose of 2.000 mg/kg by gavage to rats. Signs and symptoms of toxicity were determined according to the Hippocratic screening test and compared with the control group. In addition, a necropsy was performed for macroscopic evaluation of the organs in the abdominal cavity. A powder was obtained from aqueous extracts that showed the same organoleptic characteristics and emulsification capacity as those presented by the fresh root when prepared according to popular tradition. The LD50 was greater than the test dose with three animals surviving. On the other hand, necropsy of dead rats showed necrosis and reduction in lung mass, in addition to the presence of foam and excessive distension of the stomach and intestines. The main symptoms of toxicity were anesthesia, ataxia, sedation, loss of muscle strength, and excessive drowsiness in the first 24 hours. There was no difference between the control and extract groups with regard to body mass, food, and water intake, as well as in macroscopy of the heart, liver, lungs, intestines, spleen, pancreas, and kidneys. The aqueous extract of the B. floribunda was considered nontoxic or of very low toxicity. However, it is capable of altering the activity of the central nervous system and causing disorders in the respiratory and digestive systems.


Assuntos
Casca de Planta , Extratos Vegetais , Raízes de Plantas , Animais , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Ratos , Casca de Planta/química , Masculino , Raízes de Plantas/química , Dose Letal Mediana , Feminino , Testes de Toxicidade Aguda , Ratos Wistar , Modelos Animais
2.
BMC Vet Res ; 20(1): 303, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982442

RESUMO

BACKGROUND: The inappropriate use of pesticides including fungicides creates severe biological hazards that can endanger fish health and impede sustainable aquaculture. OBJECTIVE: This study investigated the negative impacts of metiram (MET), a fungicide on the health status of Nile tilapia (Oreochromis niloticus) for a 96-hour duration as an acute exposure in a static renewal system. METHODS: Three hundred fish (average body weight: 37.50 ± 0.22 g) were assigned into six groups (50 fish/group) with five replicates (10 fish/replicate). Fish were exposed to various six concentrations (0, 1.5, 3, 4.5, 6, and 7.5 mg/L) of MET as a water exposure to for 96-hour without water exchange. The fish's behavior, clinical signs, and mortalities were documented every day of the exposure period. Additionally, MET's impact on blood profile, stress biomarkers, hepato-renal functions, immune-antioxidant status, and brain biomarker were closely monitored. RESULTS: The lethal concentration (LC50) of MET estimated using Finney's probit technique was 3.77 mg/L. The fish's behavior was severely impacted by acute MET exposure, as clear by an increase in surfacing, loss of equilibrium, unusual swimming, laterality, abnormal movement, and a decline in aggressive behaviors. The survivability and hematological indices (white and red blood cell count, differential white blood cell count, hematocrit value, and hemoglobin) were significantly reduced in a concentration-dependent manner following MET exposure. Acute exposure to MET (1.5-7.5 mg/L) incrementally increased stress biomarkers (nor-epinephrine, cortisol, and glucose), lipid peroxides (malondialdehyde), and brain oxidative DNA damage biomarker (8-hydroxy-2-deoxyguanosine). A hepato-renal dysfunction by MET exposure (4.5-7.5 mg/L) was evidenced by the significant increase in the alanine and aspartate aminotransferases and creatinine values. Moreover, a substantial decline in the immune parameters (lysozyme, complement 3, serum bactericidal activity, and antiprotease activity) and antioxidant variables (total antioxidant capacity, superoxide dismutase, and glutathione peroxidase) resulted from acute MET exposure. CONCLUSION: According to these findings, the 96-hour LC50 of MET in Nile tilapia was 3.77 mg/L. MET exposure triggered toxicity in Nile tilapia, as seen by alterations in fish neuro-behaviors, immune-antioxidant status, hepato-renal functioning, and signifying physiological disturbances. This study emphasizes the potential ecological dangers provoked by MET as an environmental contaminant to aquatic systems. However, the long-term MET exposure is still needed to be investigated.


Assuntos
Ciclídeos , Fungicidas Industriais , Animais , Ciclídeos/metabolismo , Ciclídeos/fisiologia , Fungicidas Industriais/toxicidade , Poluentes Químicos da Água/toxicidade , Comportamento Animal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Biomarcadores/sangue , Dose Letal Mediana , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos
3.
Bull Exp Biol Med ; 177(1): 44-46, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38955851

RESUMO

The acute toxicity of chlorophyllin and trolox upon intraperitoneal injection of their solutions was studied in male ICR (CD-1) mice. The LD50 of chlorophyllin was found to be 633±37.2 µg/g body weight, which is lower than the LD50 of established radioprotectors. Trolox is technically non-toxic under the conditions of our study. The results obtained highlight the need for a detailed study of the radioprotective properties of trolox and chlorophyllin.


Assuntos
Clorofilídeos , Cromanos , Camundongos Endogâmicos ICR , Protetores contra Radiação , Animais , Masculino , Protetores contra Radiação/farmacologia , Clorofilídeos/farmacologia , Cromanos/farmacologia , Camundongos , Dose Letal Mediana , Antioxidantes/farmacologia , Injeções Intraperitoneais
4.
Environ Geochem Health ; 46(9): 323, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012394

RESUMO

This study was aimed to survey toxicity of waterpipe wastes leachates on Peronia peronii in aquatic and sediment environments as two exposure media. For this, leachates of four tobacco types including burnt traditional tobacco (BTT), fresh traditional tobacco (FTT), burnt fruit-flavored tobacco (BFT) and fresh fruit-flavored tobacco (FFT)) were prepared and used to assess their toxic effects on P. peronei in two aquatic and sediment media. The in-vivo toxic effects of five different concentrations of waterpipe tobacco waste leachates on P. peronii were evaluated. The LC50 values of BTTs leachates to P. peronii were 17.50, 16.05, 11.31 and 9.38 g/L at exposure times of 24, 48, 72 and 96 h, respectively in aquatic media. These values for BFTs leachates were 14.86, 12.38, 9.53 and 7.46 g/L at exposure times of 24, 48, 72 and 96 h, respectively. In the case of sediment media, the LC50 values of BTTs leachates were 15.33, 13.70, 9.09 and 6.70 g/L at exposure times of 24, 48, 72 and 96 h, respectively while these values for BFTs leachates were 12.00, 10.32, 8.20 and 5.65 g/L. Fruit-flavored tobacco leachates had significantly higher toxicity than traditional tobacco leachates for P. peronii. The findings also showed significant differences between the LC50 values of different leachates in different media of water and sediment. The results demonstrated that even small amount of tobacco waste (~ 5 to 6 g/L) can lead to P. peronii mortality and may also pose a hazard to other aquatic and benthic organisms. The results obtained from the present study can be used as a baseline data to assess local effects causing from unsafe disposal of post-consumption tobacco waste in beach areas. In addition, these findings can lead to encouraging decision-makers to focus more on the types of tobacco waste in the municipal solid waste management system and to implement a source separation process for these wastes.


Assuntos
Sedimentos Geológicos , Tabaco para Cachimbos de Água , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Tabaco para Cachimbos de Água/toxicidade , Animais , Dose Letal Mediana , Monitoramento Ambiental/métodos , Alismatales/química
5.
Turkiye Parazitol Derg ; 48(2): 96-104, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38958415

RESUMO

Objective: Medicinal leeches (Hirudo spp.) have been used for therapeutic purposes in humans since ancient times. Because of their growth conditions, leeches carry certain bacteria and endosymbionts (e.g., Aeromonas spp). In both leech farms and hirudotherapy clinics, there are no reliable antiseptics that can be used with leeches. This study aimed to determine whether methylene blue (MB) is a safe antiseptic for medicinal leeches and assess its safe usage. Methods: This study evaluated the efficacy of MB by determining lethal concentrations (LC), effective concentrations (EC), and lethal times (LT) for the medicinal leech Hirudo verbena Carena, 1820. A total of 570 H. verbana specimens obtained from a local farm were used in this study. Eighteen different concentrations of MB (between 1 ppm and 512 ppm) were tested. Results: The LC50 and EC50 values for H. verbana were determined to be 60.381 (53.674-66.636) ppm and 2.013 (1.789-2.221) ppm, respectively. The LT50 durations for MB concentrations of 32 and 512 ppm were calculated as 212.92 h (138.43 h-1485.78 h) and 17.82 h (8.08 h-23.90 h), respectively. Conclusion: The results show that MB concentrations between 2 and 19 ppm can be safely used as antiseptics in hirudotherapy clinics and leech farms to address bacterial concerns caused by medicinal leeches.


Assuntos
Anti-Infecciosos Locais , Sanguessugas , Azul de Metileno , Animais , Anti-Infecciosos Locais/farmacologia , Aplicação de Sanguessugas , Aeromonas/efeitos dos fármacos , Dose Letal Mediana , Hirudo medicinalis , Animais Peçonhentos
6.
Pharm Biol ; 62(1): 577-591, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39016037

RESUMO

CONTEXT: The botanical species Bauhinia guianensis Aublet (Leguminosae-Cercidoideae) is traditionally used in the Amazon for medicinal purposes. OBJECTIVE: The acute toxicity of the hydroethanolic extracts from B. guianensis leaves and stems (HELBg and HESBg) was evaluated in zebrafish (Danio rerio), with emphasis on the embryonic developmental stage and adult alterations. MATERIALS AND METHODS: Extracts were analyzed on LC-DAD-MS/MS. Zebrafish eggs were inoculated individually with concentrations of HELBg and HESBg (0.25, 0.5, 0.75, 1.0, and 1.5 µg/mL), observed for 96 h. Adult zebrafish were treated with a single oral dose (100, 200, 500, 1000, and 2000 mg/kg) of HELBg and HESBg, observed for 48 h. RESULTS: HELBg and HESBg analysis detected 55 compounds. Both extracts exhibited toxicity, including embryo coagulation at higher doses of HELBg and absence of heartbeats in embryos at all doses of HESBg. Behavioral variations were observed; tissue alterations in adult zebrafish were found at the highest doses, primarily in the liver, intestine, and kidneys because of HELBg and HESBg effects. The LD50 of HESBg was 1717 mg/kg, while HELBg exceeded the limit dose of 2000 mg/kg. CONCLUSIONS: The study on acute toxicity of B. guianensis extracts exhibits significant toxic potential, emphasizing effects on embryonic and adult zebrafish. The results suggest relative safety of the species preparations, encouraging further clinical trials on potential biological activities.


Assuntos
Bauhinia , Embrião não Mamífero , Extratos Vegetais , Folhas de Planta , Testes de Toxicidade Aguda , Peixe-Zebra , Animais , Extratos Vegetais/toxicidade , Extratos Vegetais/isolamento & purificação , Bauhinia/química , Embrião não Mamífero/efeitos dos fármacos , Dose Letal Mediana , Relação Dose-Resposta a Droga , Caules de Planta , Etanol/toxicidade , Espectrometria de Massas em Tandem , Masculino , Solventes/química , Feminino
7.
Recent Pat Nanotechnol ; 18(3): 350-360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38847137

RESUMO

BACKGROUND: Lepidium sativum (LS) seed extract has various pharmacological properties, such as antioxidant, hepatoprotective, and anticancer activities. However, the translation of L. sativum seed extract to the clinical phase is still tedious due to its bioavailability and stability issues. This problem can be solved by encapsulating it in a nanodelivery system to improve its therapeutic potency. METHODS: In this study, we have determined and compared the in vivo toxicity of ethanolic extracts of L. sativum seeds (EELS) and solid lipid nanoparticles (SLNs). To conduct toxicity (acute and subacute toxicity) assessments, EELS and SLNs were orally administered to Swiss albino mice. Animal survival, body weight, the weight of vital organs in relation to body weight, haematological profile, biochemistry profile, and histopathological alterations were examined. RESULTS: Animals administered with 2000 mg/kg and 5000 mg/kg in an acute toxicity study exhibited no toxicological symptoms regarding behaviour, gross pathology, and body weight. As per a study on acute toxicity, the LD50 (lethal dose) for SLNs and EELS was over 400 mg/kg and over 5000 mg/kg, respectively. When animals were given SLNs (50 and 100 mg/kg, orally) and EELS (250, 500, and 1000 mg/kg, orally) for 28 days, subacute toxicity study did not exhibit any clinical changes. There were no differences in weight gain, haematological parameters, or biochemical parameters compared to the control groups (p > 0.05). The organs of the treated animals showed no abnormalities in the histological analysis (liver, heart, kidney, and spleen). CONCLUSION: The result confirms ethanolic extracts of L. sativum seeds and their SLNs to not have harmful effects following acute and subacute administration to mice. For further studies, patents available on Lepidium may be referred for its preclinical and clinical applications.


Assuntos
Lepidium sativum , Nanopartículas , Extratos Vegetais , Sementes , Animais , Camundongos , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Extratos Vegetais/administração & dosagem , Sementes/química , Administração Oral , Nanopartículas/química , Nanopartículas/toxicidade , Testes de Toxicidade Aguda , Masculino , Feminino , Dose Letal Mediana , Testes de Toxicidade Subaguda
8.
Toxins (Basel) ; 16(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38922173

RESUMO

(1) Background: At present, the only potency assay approved in China for the in-country testing of botulinum toxin type A for injection products is the mouse bioassay (MBA). The Chinese market for neurotoxin products is rapidly expanding, but MBAs are subject to high variability due to individual variations in mice, as well as variations in injection sites, in addition to the limited number of batches tested for one MBA. Compared with the mLD50 method, the cell-based potency assay (CBPA) developed for the potency testing of onabotulinumtoxinA (BOTOX) by AbbVie not only does not use any experimental animals but also allows for significant time and cost savings. Due to the significant benefits conferred by the replacement of the mLD50 assay with CBPA in China, the CBPA method has been transferred, validated, and cross-validated to demonstrate the equivalence of the two potency methods. (2) Methods: The differentiated SiMa cells were treated with both BOTOX samples and the reference standard, and the cleaved SNAP25197 in the cell lysates was quantified using Chemi-ECL ELISA. A 4-PL model was used for the data fit and sample relative potency calculation. The method accuracy, linearity, repeatability, and intermediate precision were determined within the range of 50% to 200% of the labeled claim. A statistical equivalence of the two potency methods (CBPA and mLD50) was initially demonstrated by comparing the AbbVie CBPA data with NIFDC mLD50 data on a total of 167 commercial BOTOX lots (85 50U lots and 82 100U lots). In addition, six lots of onabotulinumtoxinA (three 50U and three 100U) were re-tested as cross-validation by these two methods for equivalence. (3) Results: The overall assay's accuracy and intermediate precision were determined as 104% and 9.2%, and the slope, R-square, and Y-intercept for linearity were determined as 1.071, 0.998, and 0.036, respectively. The repeatability was determined as 6.9%. The range with the acceptable criteria of accuracy, linearity, and precision was demonstrated as 50% to 200% of the labeled claim. The 95% equivalence statistic test using margins [80%, 125%] indicates that CBPA and mLD50 methods are equivalent for both BOTOX strengths (i.e., 50U and 100U). The relative potency data from cross-validation were within the range of ≥80% to ≤120%. (4) Conclusions: The CBPA meets all acceptance criteria and is equivalent to mLD50. The replacement of mLD50 with CBPA is well justified in terms of ensuring safety and efficacy, as well as for animal benefits.


Assuntos
Bioensaio , Toxinas Botulínicas Tipo A , Toxinas Botulínicas Tipo A/toxicidade , Toxinas Botulínicas Tipo A/farmacologia , Animais , Camundongos , Bioensaio/métodos , Dose Letal Mediana , Reprodutibilidade dos Testes , Linhagem Celular , Humanos
9.
Vet Med Sci ; 10(4): e1494, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38853588

RESUMO

BACKGROUND: Heavy metals are one of the most important environmental pollutants in marine coastal ecosystems. Cadmium is a heavy metal that enters to marine environments via industrial wastes and oil production activities. OBJECTIVES: This study were done to determine the toxicity of cadmium to Litopenaeus vannamei and to evaluate the histological changes in gill tissues after exposure to sublethal concentrations of cadmium at different salinities. METHODS: For this reason, toxicity test was done to determine the lethal concentration (LC50) of cadmium for whiteleg shrimp. According to the calculated LC50 amount, sublethal doses of cadmium were used to determine its histological effects in different salinity during 2 weeks exposing period. RESULTS: LC50 of cadmium for 96 h for whiteleg shrimp was 6.56 mg/L. Histological alterations in the gill were observed in L. vannamei after 14 days exposure to different concentrations of cadmium and salinity. Histopathological index was increased in a dose-dependent manner. CONCLUSION: Our findings showed that doses lower than 2 mg/L have repairable effects on gill structure, but the concentration of 2 mg/L cadmium leaves irreparable and destructive effects on the gill tissue.


Assuntos
Cádmio , Brânquias , Penaeidae , Salinidade , Poluentes Químicos da Água , Animais , Penaeidae/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Brânquias/patologia , Cádmio/toxicidade , Poluentes Químicos da Água/toxicidade , Dose Letal Mediana , Relação Dose-Resposta a Droga
10.
Environ Toxicol Chem ; 43(7): 1627-1637, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38837458

RESUMO

Shipping activities are increasing with sea ice receding in the Arctic, leading to higher risks of accidents and oil spills. Because Arctic toxicity data are limited, oil spill risk assessments for the Arctic are challenging to conduct. In the present study, we tested if acute oil toxicity metrics obtained at temperate conditions reflect those at Arctic conditions. The effects of temperature (4 °C, 12 °C, and 20 °C) on the median lethal concentration (LC50) and the critical body residue (CBR) of the temperate invertebrate Gammarus locusta exposed to water accommodated fractions of a fuel oil were determined. Both toxicity metrics decreased with increasing temperature. In addition, data for the temperate G. locusta were compared to data obtained for Arctic Gammarus species at 4 °C. The LC50 for the Arctic Gammarus sp. was a factor of 3 higher than that for the temperate G. locusta at 4 °C, but its CBR was similar, although both the exposure time and concentration were extended to reach lethality. Probably, this was a result of the larger size and higher weight and total lipid content of Arctic gammarids compared to the temperate gammarids. Taken together, the present data support the use of temperate acute oil toxicity data as a basis for assessing risks in the Arctic region, provided that the effects of temperature on oil fate and functional traits (e.g., body size and lipid content) of test species are considered. As such, using the CBR as a toxicity metric is beneficial because it is independent of functional traits, despite its temperature dependency. To the best of our knowledge, the present study is the first to report CBRs for oil. Environ Toxicol Chem 2024;43:1627-1637. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Anfípodes , Poluição por Petróleo , Temperatura , Poluentes Químicos da Água , Animais , Regiões Árticas , Anfípodes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Petróleo/toxicidade , Dose Letal Mediana
11.
Parasit Vectors ; 17(1): 251, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858771

RESUMO

BACKGROUND: Salinity, exacerbated by rising sea levels, is a critical environmental cue affecting freshwater ecosystems. Predicting ecosystem structure in response to such changes and their implications for the geographical distribution of arthropod disease vectors requires further insights into the plasticity and adaptability of lower trophic level species in freshwater systems. Our study investigated whether populations of the mosquito Culex pipiens, typically considered sensitive to salt, have adapted due to gradual exposure. METHODS: Mesocosm experiments were conducted to evaluate responses in life history traits to increasing levels of salinity in three populations along a gradient perpendicular to the North Sea coast. Salt concentrations up to the brackish-marine transition zone (8 g/l chloride) were used, upon which no survival was expected. To determine how this process affects oviposition, a colonization experiment was performed by exposing the coastal population to the same concentrations. RESULTS: While concentrations up to the currently described median lethal dose (LD50) (4 g/l) were surprisingly favored during egg laying, even the treatment with the highest salt concentration was incidentally colonized. Differences in development rates among populations were observed, but the influence of salinity was evident only at 4 g/l and higher, resulting in only a 1-day delay. Mortality rates were lower than expected, reaching only 20% for coastal and inland populations and 41% for the intermediate population at the highest salinity. Sex ratios remained unaffected across the tested range. CONCLUSIONS: The high tolerance to salinity for all key life history parameters across populations suggests that Cx. pipiens is unlikely to shift its distribution in the foreseeable future, with potential implications for the disease risk of associated pathogens.


Assuntos
Culex , Oviposição , Salinidade , Animais , Culex/fisiologia , Culex/efeitos dos fármacos , Culex/crescimento & desenvolvimento , Feminino , Masculino , Ecossistema , Tolerância ao Sal , Água Doce , Características de História de Vida , Mosquitos Vetores/fisiologia , Dose Letal Mediana , Cloreto de Sódio/farmacologia
12.
Sci Total Environ ; 944: 174014, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38880156

RESUMO

The threat of neonicotinoids to insect pollinators, particularly honeybees (Apis mellifera), is a global concern, but the risk of chiral neonicotinoids to insect larvae remains poorly understood. In the current study, we evaluated the acute and chronic toxicity of dinotefuran enantiomers to honeybee larvae in vitro and explored the mechanism of toxicity. The results showed that the acute median lethal dose (LD50) of S-dinotefuran to honeybee larvae was 30.0 µg/larva after oral exposure for 72 h, which was more toxic than rac-dinotefuran (92.7 µg/larva) and R-dinotefuran (183.6 µg/larva). Although the acute toxicity of the three forms of dinotefuran to larvae was lower than that to adults, chronic exposure significantly reduced larval survival, larval weight, and weight of newly emerged adults. Analysis of gene expression and hormone titer indicated that dinotefuran affects larval growth and development by interfering with nutrient digestion and absorption and the molting system. Analysis of hemolymph metabolome further revealed that disturbances in the neuroactive ligand-receptor interaction pathway and energy metabolism are the key mechanisms of dinotefuran toxicity to bee larvae. In addition, melatonin and vitellogenin are used by larvae to cope with dinotefuran-induced oxidative stress. Our results contribute to a comprehensive understanding of dinotefuran damage to bees and provide new insights into the mechanism of enantioselective toxicity of insecticides to insect larvae.


Assuntos
Guanidinas , Inseticidas , Larva , Neonicotinoides , Nitrocompostos , Animais , Abelhas/efeitos dos fármacos , Neonicotinoides/toxicidade , Larva/efeitos dos fármacos , Guanidinas/toxicidade , Nitrocompostos/toxicidade , Inseticidas/toxicidade , Estereoisomerismo , Dose Letal Mediana
13.
Aquat Toxicol ; 272: 106979, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823072

RESUMO

Tris(2-chloroethyl) phosphate (TCEP) and tris(1­chloro-2-propyl) phosphate (TCPP) are widely used as chlorinated organophosphate flame retardants (OPFRs) due to their fire-resistance capabilities. However, their extensive use has led to their permeation and pollution in aquatic environments. Using amphibians, which are non-model organisms, to test the toxic effects of OPFRs is relatively uncommon. This study examined the acute and chronic toxicity differences between TCEP and TCPP on Polypedates megacephalus tadpoles and evaluated the potential ecological risks to tadpoles in different aquatic environments using the risk quotient (RQ). In acute toxicity assay, the tadpole survival rates decreased with increased exposure time and concentrations, with TCEP exhibiting higher LC50 values than TCPP, at 305.5 mg/L and 70 mg/L, respectively. In the chronic assay, prolonged exposure to 300 µg/L of both substances resulted in similar adverse effects on tadpole growth, metamorphosis, and hepatic antioxidant function. Based on RQ values, most aquatic environments did not pose an ecological risk to tadpoles. However, the analysis showed that wastewater presented higher risks than rivers and drinking water, and TCPP posed a higher potential risk than TCEP in all examined aquatic environments. These findings provide empirical evidence to comprehend the toxicological effects of OPFRs on aquatic organisms and to assess the safety of aquatic environments.


Assuntos
Anuros , Retardadores de Chama , Larva , Organofosfatos , Compostos Organofosforados , Poluentes Químicos da Água , Animais , Retardadores de Chama/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Compostos Organofosforados/toxicidade , Medição de Risco , Organofosfatos/toxicidade , Anuros/crescimento & desenvolvimento , Metamorfose Biológica/efeitos dos fármacos , Testes de Toxicidade Aguda , Dose Letal Mediana
14.
Proc Biol Sci ; 291(2024): 20232811, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38864325

RESUMO

Pesticides have been identified as major drivers of insect biodiversity loss. Thus, the study of their effects on non-pest insect species has attracted a lot of attention in recent decades. In general toxicology, the 'gold standard' to assess the toxicity of a substance is to measure mass-specific LD50 (i.e. median lethal dose per unit body mass). In entomology, reviews attempting to compare these data across all available studies are lacking. To fill this gap in knowledge, we performed a systematic review of the lethality of imidacloprid for adult insects. Imidacloprid is possibly the most extensively studied insecticide in recent times, yet we found that little is comparable across studies, owing to both methodological divergence and missing estimates of body mass. By accounting for body mass whenever possible, we show how imidacloprid sensitivity spans across an apparent range of approximately six orders of magnitude across insect species. Very high variability within species can also be observed owing to differences in exposure methods and observation time. We suggest that a more comparable and comprehensive approach has both biological and economic relevance. Ultimately, this would help to identify differences that could direct research towards preventing non-target species from being negatively affected.


Assuntos
Imidazóis , Insetos , Inseticidas , Neonicotinoides , Nitrocompostos , Especificidade da Espécie , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Animais , Inseticidas/toxicidade , Insetos/efeitos dos fármacos , Imidazóis/toxicidade , Dose Letal Mediana
15.
Birth Defects Res ; 116(6): e2368, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873958

RESUMO

BACKGROUND: Nanoplastics can be considered a novel contaminant for the environment because of their extensive applications in modern society, which represents a possible threat to humans. Nevertheless, the negative effect of polystyrene nanoplastics (PS-NPs) on male reproduction, fertility, and progeny outcomes is not well known. Thus, the aim of the present work was to calculate the median lethal dose (LD50) and investigate the consequences of exposure to PS-NPs (25 nm) on male reproductive toxicity. METHODS: This investigation first determined the LD50 of PS-NPs in male Wistar rats, and then in a formal study, 24 rats were distributed into three groups (n = 8): the control group; the low-dose group (3 mg/kg bw); and the high-dose group (10 mg/kg bw) of PS-NPs administered orally for 60 days. On the 50th day of administration, the fertility test was conducted. RESULTS: The LD50 was determined to be 2500 mg/kg. PS-NP administration induced significant alternations, mainly indicating mortality in the high-dose group, a significant elevation in body weight gain, declined sperm quality parameters, altered reproductive hormonal levels, thyroid endocrine disruption, an alternation of the normal histo-architecture and the histo-morphometric analysis of the testes, and impaired male fertility. CONCLUSION: Altogether, the current findings provide novel perspectives on PS-NP general toxicity with specific reference to male reproductive toxicity.


Assuntos
Poliestirenos , Ratos Wistar , Reprodução , Testículo , Animais , Masculino , Testículo/efeitos dos fármacos , Testículo/metabolismo , Poliestirenos/toxicidade , Ratos , Reprodução/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Administração Oral , Fertilidade/efeitos dos fármacos , Nanopartículas/toxicidade , Microplásticos/toxicidade , Dose Letal Mediana , Hormônios/metabolismo , Espermatozoides/efeitos dos fármacos
16.
PLoS One ; 19(5): e0302657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787908

RESUMO

Ethnopharmacological relevance of Saussurea species for anti-cancer compounds instigated us to develop chemotherapeutic herbal tablets. This study was an ongoing part of our previous research based on the scientific evaluation of Saussurea heteromalla (S. heteromalla) for anti-cancer lead compounds. In the current study, S. heteromalla herbal tablets (500 /800 mg) were designed and evaluated for anti-cancer activity. Arctigenin was found as a bioactive lead molecule with anti-cancer potential for cervical cancer. The in vitro results on the HeLa cell line supported the ethnopharmacological relevance and traditional utilization of S. heteromalla and provided the scientific basis for the management of cervical cancer as proclaimed by traditional practitioners in China. LD50 of the crude extract was established trough oral acute toxicity profiling in mice, wherein the minimum lethal dose was noticed as higher than 1000 mg/kg body weight orally. Chromatographic fingerprint analysis ensured the identity and consistency of S. heteromalla in herbal tablets in terms of standardization of the herbal drug. About 99.15% of the drug (S. heteromalla crude extract) was recovered in herbal tablets (RSD: 0.45%). In vitro drug release profile was found to be more than 87% within 1 h, which was also correlated with different mathematical kinetic models of drug release (r2 = 0.992), indicating that drug release from matrix tablets into the blood is constant throughout the delivery. The dosage form was found stable after an accelerated stability parameters study which may be used for anti-cervical cancer therapy in the future, if it qualifies successful preclinical investigation parameters.


Assuntos
Extratos Vegetais , Saussurea , Saussurea/química , Animais , Humanos , Camundongos , Células HeLa , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Extratos Vegetais/farmacologia , Lignanas/farmacologia , Lignanas/química , Feminino , Furanos/toxicidade , Furanos/química , Furanos/farmacologia , Comprimidos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Masculino , Antineoplásicos/farmacologia , Antineoplásicos/química , Dose Letal Mediana , Testes de Toxicidade Aguda , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/toxicidade , Medicamentos de Ervas Chinesas/farmacologia
17.
J Helminthol ; 98: e43, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38800903

RESUMO

Entomopathogenic nematodes (EPNs) are closely associated with Popillia japonica and potentially used as their biological control agents, although field results proved inconsistent and evoked a continual pursuit of native EPNs more adapted to the environment. Therefore, we surveyed the Azorean Archipelago to isolate new strains of Heterorhabditis bacteriophora and to evaluate their virulence against the model organism Galleria mellonella under laboratory conditions. Six strains were obtained from pasture and coastal environments and both nematode and symbiont bacteria were molecularly identified. The bioassays revealed that Az172, Az186, and Az171 presented high virulence across the determination of a lethal dose (LD50) and short exposure time experiments with a comparable performance to Az29. After 72 hours, these virulent strains presented a mean determination of a lethal dose of 11 infective juveniles cm-2, a lethal time (LT50) of 34 hours, and achieved 40% mortality after an initial exposure time of only 60 minutes. Az170 exhibited an intermediate performance, whereas Az179 and Az180 were classified as low virulent strains. However, both strains presented the highest reproductive potential with means of 1700 infective juveniles/mg of larvae. The bioassays of the native EPNs obtained revealed that these strains hold the potential to be used in biological control initiatives targeting P. japonica because of their high virulence and locally adapted to environmental conditions.


Assuntos
Controle Biológico de Vetores , Rhabditoidea , Animais , Açores , Virulência , Rhabditoidea/microbiologia , Rhabditoidea/fisiologia , Larva/microbiologia , Mariposas/parasitologia , Agentes de Controle Biológico , Bioensaio , Rabditídios/fisiologia , Dose Letal Mediana
18.
Acta Trop ; 255: 107230, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38714240

RESUMO

The scorpion Aegaeobuthus nigrocinctus inhabits areas in Turkey and the Levant region of the Middle East where severe/lethal envenomings have been reported. Previous research indicated its extreme venom lethality to vertebrates and distinct envenomation syndrome. We report on the composition of A. nigrocinctus venom from Lebanese specimens using nESI-MS/MS, MALDI-TOF MS, SDS-PAGE and RP-HPLC. Venom lethality in mice was also assessed (LD50 = 1.05 (0.19-1.91) mg/kg, i.p), confirming A. nigrocinctus venom toxicity from Levantine populations. Forty-seven peaks were resolved using RP-HPLC, 25 of which eluted between 20 and 40 % acetonitrile. In reducing SDS-PAGE, most predominant components were <10 kDa, with minor components at higher molecular masses of 19.6, 26.1, 46.3 and 57.7 kDa. MALDI-TOF venom fingerprinting detected 20 components within the 1,000-12,000 m/z range. Whole venom 'shotgun' bottom-up nLC-MS/MS approach, combined with in-gel tryptic digestion of SDS-PAGE bands, identified at least 67 different components belonging to 15 venom families, with ion channel-active components (K+ toxins (23); Na+ toxins (20); Cl- toxins (2)) being predominant. The sequence of a peptide (named α-KTx9.13) ortholog to Leiurus hebraeus putative α-KTx9.3 toxin was fully determined, which exhibited 81-96 % identity to other members of the α-KTx9 subfamily targeting Kv1.x and Ca2+-activated K+ channels. Chlorotoxin-like peptides were also identified. Our study underscores the medical significance of A. nigrocinctus in the region and reveals the potential value of its venom components as lead templates for biomedical applications. Future work should address whether available antivenoms in the Middle East are effective against A. nigrocinctus envenoming in the Levant area.


Assuntos
Eletroforese em Gel de Poliacrilamida , Venenos de Escorpião , Escorpiões , Animais , Escorpiões/química , Venenos de Escorpião/química , Venenos de Escorpião/toxicidade , Camundongos , Cromatografia Líquida de Alta Pressão , Dose Letal Mediana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Proteômica , Masculino , Proteoma/análise , Oriente Médio , Análise de Sobrevida , Peso Molecular
19.
Microb Pathog ; 191: 106675, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705216

RESUMO

Bovine mastitis, caused by Streptococcus agalactiae (Group B Streptococcus; GBS), poses significant economic challenges to the global dairy industry. Mouse models serves as valuable tools for assessing GBS-induced infections as an alternative to large animals. This study aimed to investigate the LD50 dose, organ bacterial load, and quantification of peritoneal leukocyte populations for GBS serotypes Ia and II isolates from China and Pakistan. Additionally, we measured indicators such as lactoferrin, albumin, and myeloperoxidase (MPO) activity. Pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, and IL-2) and anti-inflammatory cytokines (IL-10 and TGF-ß) in serum and tissue samples were evaluated using ELISA and qPCR, respectively. BALB/c mice (4 mice per group) received individual intraperitoneal injections of 100 µl containing specific bacterial inoculum concentrations (ranging from 105 to 109 CFU per mouse) of Chinese and Pakistani GBS isolates (serotypes Ia and II). Control groups received 100 µL of sterile PBS. Results revealed that the LD50 bacterial dose causing 50 % mortality in mice was 107 CFU. The highest bacterial load in all experimental groups was quantified in the peritoneum, followed by blood, mammary gland, liver, spleen, lungs, and brain. The most significant bacterial dissemination was observed in mice inoculated with Pakistani serotype Ia at 24 h, with a subsequent notable decline in bacterial counts at day 3. Notably, infection with Pakistani serotype Ia showed a trend of increased total leukocyte counts, significantly higher than Pakistani serotype II, Chinese Serotype Ia, and Chinese serotype II. A substantial influx of neutrophils and lymphocytes was observed in response to all tested serotypes, with Pakistani serotype Ia inducing a significantly higher influx compared to other groups (Pakistani serotype II, Chinese serotype Ia, and Chinese serotype II). Furthermore, TNF-α, IL-1ß, IL-2, and IL-6 expressions were significantly increased in mice one day after infection with the Pakistani serotype Ia. Compared to mice infected with the Pakistani serotype II, Chinese Serotype Ia, and Chinese serotype II, those infected with the Pakistani serotype Ia isolate exhibited the highest production of IL-10 and TGF-ß, along with significantly increased concentrations of lactoferrin, albumin, and MPO. These findings suggest that the persistence and severity of infection caused by the Pakistani serotype Ia may be linked to its ability to spread to deeper tissues. This study enhances our understanding of the clinical characteristics of bovine mastitis caused by S. agalactiae in China and Pakistan.


Assuntos
Citocinas , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Sorogrupo , Infecções Estreptocócicas , Streptococcus agalactiae , Animais , Streptococcus agalactiae/patogenicidade , Streptococcus agalactiae/classificação , Streptococcus agalactiae/imunologia , Streptococcus agalactiae/genética , Camundongos , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/imunologia , China , Citocinas/metabolismo , Citocinas/sangue , Feminino , Paquistão , Carga Bacteriana , Bovinos , Dose Letal Mediana , Mastite Bovina/microbiologia
20.
Chemosphere ; 360: 142387, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801905

RESUMO

This study was designed to investigate the toxic effects of two frequently used commercial insecticides containing endosulfan and indoxacarb on a freshwater amphipod Gammarus kischineffensis. In this context, the 24, 48, 72 and 96 h LC50 values of these pesticides were determined for G. kischineffensis. Then the histopathological effects of these pesticides on the gill tissues of this species were evaluated. At the end of the study, the 96 h LC50 values of commercial-grade endosulfan and indoxacarb for G. kischineffensis were determined as 1.861 µg L-1 and 20.212 mg L-1, respectively. Histopathologically, the most common histopathological alterations in individuals exposed to sublethal concentrations of commercial-grade endosulfan and indoxacarb were pillar cell hypertrophy resulting in atrophy of the hemocoelic space and hemocytic infiltration. Considering these results, it can be said that commercial-grade endosulfan is extremely and indoxacarb is slightly toxic to G. kischineffensis.


Assuntos
Anfípodes , Endossulfano , Inseticidas , Oxazinas , Poluentes Químicos da Água , Animais , Anfípodes/efeitos dos fármacos , Endossulfano/toxicidade , Inseticidas/toxicidade , Oxazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/patologia , Dose Letal Mediana
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