ABSTRACT
Nanotechnology has been used to apply nanoparticle essential elements to enhance the ability of animals to absorb these elements and consequently improve their reproductive performance. High concentrations of nanoparticles (NPs) can directly harm a range of aquatic life forms, ultimately contributing to a decline in biodiversity. Helisoma duryi snails are a good model for studying the toxicological effects of bulk zinc oxide (ZnO-BPs) and nano zinc oxide (ZnO-NPs) on freshwater gastropods. This study aimed to compare the toxic effects of ZnO-BPs and ZnO-NPs on H. duryi snails and explore how waterborne and dietary exposure influenced the reproductive performance of this snail. ZnO-BPs and ZnO-NPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray powder (XRD). This study revealed that the size of ZnO-BPs and ZnO-NPs were 154 nm and 11-31 nm, respectively. The results showed that exposure of adult snails to sub-lethal concentrations of both ZnO forms (bulk and nano) for 24 h/week for 4 weeks markedly changed their reproductive performance in a concentration-dependent manner, where fecundity was negatively affected by high concentrations. It was concluded that dietary exposure to the lowest tested concentration of ZnO-NPs (1 ppm) has a positive effect as the number of eggs and egg masses/snails increased and the incubation period decreased. Also, poly-vitelline eggs (The formation of twins) were observed. ZnO-NPs at low concentrations positively affect the reproductive performance of snails, especially after dietary exposure. The results revealed that 1 ppm ZnO-NPs could be supplementary provided to snails to improve their fertility, reduce the developmental time course, increase hatchability percentage, and produce poly-vitelline eggs.
Subject(s)
Reproduction , Snails , Zinc Oxide , Animals , Zinc Oxide/administration & dosage , Zinc Oxide/toxicity , Snails/drug effects , Snails/physiology , Reproduction/drug effects , Water Pollutants, Chemical/toxicity , Nanoparticles/toxicity , Female , Metal Nanoparticles/toxicityABSTRACT
Schistosomiasis is a serious health issue in tropical regions, and natural compounds have gained popularity in medical science. This study investigated the potential effects of pumpkin seed oil (PSO) on Biomphalaria [B.] alexandrina snails (Ehrenberg, 1831), Schistosoma [S.] mansoni (Sambon, 1907) miracidium, and cercariae. The chemical composition of PSO was determined using gas chromatography/mass spectrometry. A bioassay was performed to evaluate the effects of PSO on snails, miracidia, and cercariae. The results showed no significant mortality of B. alexandrina snails after exposure to PSO, but it caused morphological changes in their hemocytes at 1.0 mg/ml for 24 hours. PSO exhibited larvicidal activity against miracidia after 2 hours of exposure at a LC50 of 618.4 ppm. A significant increase in the mortality rate of miracidia was observed in a dose- and time-dependent manner, reaching a 100% death rate after 10 minutes at LC90 and 15 minutes at LC50 concentration. PSO also showed effective cercaricidal activity after 2 hours of exposure at a LC50 of 290.5 ppm. Histological examination revealed multiple pathological changes in the digestive and hermaphrodite glands. The PSO had genotoxic effects on snails, which exhibited a significant increase [p≤0.05] in comet parameters compared to the control. The findings suggest that PSO has potential as a molluscicide, miracidicide, and cercaricide, making it a possible alternative to traditional molluscicides in controlling schistosomiasis.
Subject(s)
Biomphalaria , Cucurbita , Molluscacides , Schistosomiasis , Animals , Schistosoma mansoni , Snails , Cercaria , Molluscacides/pharmacology , Plant Oils/pharmacologyABSTRACT
Snails are important agricultural pests difficult to control, but data regarding molluscicidal assays are scant. Stemona alkaloids are typical secondary metabolites for the taxa and have been broadly investigated for their pharmacological and toxicological effects. This makes it possible for us to further develop the toxicities of these compounds to snails. In this work, we tested the antifeedant properties of leaves from seven Chinese Stemona species against the land snail species Bradybaena ravida in choice and non-choice feeding assays. The tested leaves Stemona parviflora exhibited the most deterrent effects, and a further phytochemical investigation of aerial parts led to the identification of 16 alkaloids. Among them, three novel alkaloids could be identified. The alkaloidal fraction and single alkaloids were further assayed against this snail species, and the results suggest a cocktail effect because the impact of the alkaloidal fraction was higher than the effects caused by single alkaloids. The study can promote the search process of natural antimollusc products from plants to control snails.
Subject(s)
Alkaloids , Stemonaceae , Animals , Alkaloids/chemistry , Plant Extracts/chemistry , Snails , ChinaABSTRACT
Embryos of Ilyanassa obsoleta (from Massachusetts and Florida) and Phrontis vibex (from Florida) were exposed to temperatures from 33 to 37°C. In both species, very young embryos are especially sensitive to thermal stress. Brief early heat shock did not disturb spiral cleavage geometry but led to variable, typically severe defects in larval morphogenesis and tissue differentiation. In Ilyanassa but not P. vibex, early heat shock resulted in immediate slowing or arrest of interphase progression during early cleavage. This reversible arrest was correlated with improved prognosis for larval development and (in Massachusetts snails, at least) depended on parental acclimation to warm temperature (~25.5°C). Embryos from Massachusetts snails housed at lower temperature (16°C) exhibited cytokinesis failure when briefly incubated at 33°C during early cleavage, and tissue differentiation failure during incubation at 33°C begun at later stages. This preliminary study reveals a case in which stress-conditioned parents may endow embryos with protection against potentially lethal thermal stress during the most vulnerable stages of life.
Subject(s)
Hyperthermia, Induced , Snails , Animals , Morphogenesis , Temperature , AcclimatizationABSTRACT
OBJECTIVE: Precision interventions have been proposed in transmission-interrupted areas to further reduce the potential transmission risk of schistosomiasis. This study aimed to evaluate the effects of different interventions modes for potential transmission risk control. METHODS: Three groups of schistosomiasis-endemic villages were selected in Jiangling county, Hubei province. After baseline surveys in 2020, three intervention models were employed in 2021 and 2022. In Model 1, Oncomelania hupensis snail control in key settings and an integrated strategy with an emphasis on the infectious sources managing was employed. In Model 2, an integrated health education-led strategy with an emphasis on infectious source management was employed. In Model 3, only the integrated strategy with an emphasis on infectious source management was employed. The effects of the different intervention models were examined with multiple indicators after 2 years of intervention using the entropy-weighted technique for order of preference by similarity to ideal solution (TOPSIS), rank-sum ratio (RSR) and fuzzy combination model of entropy-weighted TOPSIS and RSR. RESULTS: Entropy-weighted TOPSIS modeling showed that the Ci values of Model 2 were 0.4434, 0.2759, and 0.3069 in the three pilot villages, Ci values were larger, with top comprehensive ranking. The results of the RSR method showed that the RSR values of Model 2 were 0.75, 0.708, and 0.736 in the three pilot villages, with top comprehensive ranking. The results from the fuzzy combination model of entropy-weighted TOPSIS and RSR showed that implementation of Model 2 resulted in the highest comprehensive ranking among the three models in the three pilot villages under Ci: RSR = 0.1: 0.9, Ci: RSR = 0.5: 0.5 and Ci: RSR = 0.9: 0.1. CONCLUSION: The integrated health education-led strategy with an emphasis on infectious source management was the optimal model to manage the risk of transmission of schistosomiasis during the post-transmission interruption phase.
Subject(s)
Schistosomiasis , Animals , Humans , Schistosomiasis/epidemiology , Schistosomiasis/prevention & control , Snails , Health Education , Surveys and Questionnaires , China/epidemiologyABSTRACT
Eremina desertorum snail mucin antioxidant and anti-inflammatory effects were investigated against carbon tetrachloride (CCl4)-intestinal inflammation and testes damage. Male albino mice were intraperitoneally injected with 0.5 ml/kg b.wt of 40% CCl4, twice a week for 8 weeks. The treated groups were treated orally with mucin (after 8 weeks of CCl4 intoxication, twice a week for 4 weeks). CCl4 caused significant increases in C-reactive protein, lipid peroxidation, interleukin-2 levels and caspase-3, while decreasing the total proteins levels, activities of catalase, superoxide dismutase, and glutathione reductase contents, testosterone and 17ß estradiol levels compared with the control mice. The improvements of these parameters occurred after treatment with E. desertorum mucin, where all the biochemical measurements tended to restore to the normal values. Histopathologically, CCl4 caused ulceration in the columnar mucin secreting cells that lined the ileal mucosa, partial loss of goblet cells, abnormal villous/crypt ratio, and submucosal infiltrate of the inflammatory cells. Also, sections of testis showed alterations in the developmental spermatogenic arrangement of the same seminiferous tubules, with no spermatozoa in the center. Improvements in these architectures occurred after administration of mucin, where sections showed almost normal histological structure. In conclusion, E. desertorum mucin could be used as a supplementary material as it has antioxidant and anti-inflammatory effects; besides it has low cost.
Subject(s)
Antioxidants , Testis , Male , Mice , Animals , Antioxidants/pharmacology , Antioxidants/metabolism , Testis/metabolism , Mucins/metabolism , Oxidative Stress , Lipid Peroxidation , Plant Extracts , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation/metabolism , Anti-Inflammatory Agents/pharmacology , Snails/metabolismABSTRACT
The current study aimed to establish simple and quick quality evaluation method of Chishao based on QAMS. Oxypaeoniflorin is used as a marker in the Chishao root. Based on it, the content of other components could be obtained by establishing the mathematical relationship. UPLC method was used to collect data, and the detection wavelengths were 230nm (benzoic acid, paeoniflorin), 263nm (hydroxy paeoniflorin) 274nm (gallic acid, paeoniflorin, catechin), respectively. The stationary phase was an Agilent ZORBAX SB-C18 and the mobile phase was acetonitrile -0.1% formic acid-water. The gradient elution method was adopted at the certain flow rate (0.3 mL/min). The column temperature set 40oC, and the injection volume was 1µL. Multiple reaction monitoring mode was selected for data collection. The linear ranges of benzoic acid, paeoniflorin, hydroxy-paeoniflorin, gallic acid, catechin and paeoniflorinhad good linearity (r ≥0.9995). The UPLC method was established to determine the content of paeoniflorin, benzoic acid, catechin, gallic acid, paeoniflorin, andhydroxy-paeoniflorin in Radix Paeoniae Rubra. In the current study, the method for the chemical components in Radix Paeoniae Rubra to provide the evaluation basis of medicinal effects.
Subject(s)
Catechin , Drugs, Chinese Herbal , Paeonia , Benzoic Acid , Bridged-Ring Compounds , Chromatography, High Pressure Liquid/methods , Gallic Acid , Monoterpenes , Paeonia/chemistry , SnailsABSTRACT
Based on UPLC characteristic chromatogram and quantitative analysis of multi-components by single marker(QAMS), the content of seven types of ginsenosides in Ginseng Radix et Rhizoma was simultaneously determined, and the quality of Ginseng Radix et Rhizoma was evaluated by the principal component analysis(PCA). The chromatographic separation was performed on the Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 µm) with the mobile phase of acetonitrile-water for gradient elution at the flow rate of 0.3 mL·min~(-1), the column temperature of 30 â, the detection wavelength of 203 nm, and the injection volume of 2 µL. The UPLC chromatogram was established with 19 batches of Ginseng Radix et Rhizoma samples from three producing areas by Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(version 2012). Thirteen characteristic peaks were determined and seven components were identified. SPSS 26.0 was used to conduct PCA on the characteristic peak areas. With the peak of ginsenoside Rb_1 as reference peak S, ginsenoside Rb_1 showed good durability of relative correction factor as compared with other ginsenosides. The QAMS method for the determination of seven ginsenosides in Ginseng Radix et Rhizoma was established. There was no significant difference in results between the QAMS method and the external standard method. As revealed by the results of PCA and the determination of the total content of seven ginsenosides, the four batches of Ginseng Radix et Rhizoma numbered S19, S18, S1, and S2 were of superior quality. The characteristic chromatogram and QAMS method for the determination of seven ginsenosides in this study were convenient and accurate, which greatly shortened the analysis time and improved the analysis efficiency. The findings of this study are expected to provide a basis for the overall quality evaluation of Ginseng Radix et Rhizoma.
Subject(s)
Drugs, Chinese Herbal , Ginsenosides , Panax , Chromatography, High Pressure Liquid , Drugs, Chinese Herbal/chemistry , Ginsenosides/analysis , Panax/chemistry , Rhizome/chemistry , SnailsABSTRACT
Schistosomiasis is a severe illness that caused socioeconomic problems. The present study aimed to investigate the molluscicidal activities of the methanolic extract of Nerium oleander and Tecoma stans on B. alexandrina snails. The present results showed that N. oleander had the higher molluscicidal effect (LC50: 138.6 mg/l) than T. stans methanolic extract (LC50: 256.0 mg/l). These concentrations had no mortality effects on Daphnia magna during the first 12 h of the exposure, while, they had a cercaricidal activity. Exposure of B. alexandrina snails to the sub lethal concentrations (LC10 and LC25) of the methanolic extract of either N. oleander or T. stans caused a concentration- dependent significant decrease in their mean total number of hemocyte and hyalinocytes percent, while, both the round small and the granulocytes were increased than the control group. Exposure of B. alexandrina snails to LC25 of the methanolic extract of N. oleander or T. stans, caused morphological alterations in the hemocytes that were studied by both light and electron microscopy. The sub lethal concentration (LC25) significantly decreased the acetyl cholinesterase activities, acid and alkaline phosphatase levels and the protein content. Histopathological changes occurred in the digestive and the hermaphrodite glands of exposed B. alexandrina snails to LC25 of the methanolic extracts. These alterations were confirmed by Immunohistochemistry for PCNA and Cyclin D1 expressions. Conclusively, these plants could be used to decrease the spread of schistosomiasis as they are cheap and environmentally safe to replace the synthetic molluscicides for snail control.
Subject(s)
Bignoniaceae , Biomphalaria , Molluscacides , Nerium , Schistosomiasis , Animals , Methanol/metabolism , Molluscacides/pharmacology , Plant Extracts/pharmacology , SnailsABSTRACT
Metal pollution poses a major threat to aquatic systems especially in anthropogenic influenced areas, in as much as metals are persistent in the environment. The freshwater snail Theodoxus fluviatilis has often been used as an indicator species for the ecological status in river monitoring. In the River Rhine, the native Northern-European form of T. fluviatilis is nowadays extinct, whilst the Danubian form is spreading along the river. The aim of our study was to investigate if the cryptic invader is affected by metal exposure present in the River Rhine and to discuss its potential as an indicator for metal pollution. Several environmental abiotic (14 water environmental variables plus five common metal concentrations in water and biofilm) and biotic parameters (biofilm mass) were measured across 23 sites along the River Rhine. Five population and six histopathological parameters were evaluated on snails collected at all 23 sites. Aqueous chromium concentration was positively correlated to the damage of male reproductive organs of T. fluviatilis, and higher ammonium concentration was correlated to a decrease in snail size and an increase in the proportion of juveniles. None of the analysed snail parameters was negatively correlated to concentrations of other metals measured, like copper and zinc. Therefore, based on the parameters evaluated, our results indicate that the Danubian form of T. fluviatilis is only restrictedly suitable as an indicator for metal pollution in the River Rhine system. Further field and laboratory investigations including other stressors are necessary to evaluate the indicator potential of the cryptic invader holistically.
Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Animals , Environmental Monitoring , Fresh Water , Geologic Sediments , Male , Metals/analysis , Metals, Heavy/toxicity , Rivers , Snails , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicityABSTRACT
Algal biofilms in streams are simultaneously controlled by light and nutrient availability (bottom-up control) and by grazing activity (top-down control). In addition to promoting algal growth, light and nutrients also determine the nutritional quality of algae for grazers. While short-term experiments have shown that grazers increase consumption rates of nutrient-poor algae due to compensatory feeding, nutrient limitation in the long run can constrain grazer growth and hence limit the strength of grazing activity. In this study, we tested the effects of light and phosphorus availability on grazer growth and thus on the long-term control of algal biomass. At the end of the experiment, algal biomass was significantly affected by light, phosphorus and grazing, but the interactive effects of the three factors significantly changed over time. At both high light and phosphorus supply, grazing did not initially reduce algal biomass, but the effect of grazing became stronger in the final three weeks of the experiment. Snail growth was enhanced by light, rather than phosphorus, suggesting that algal quantity rather than quality was the main limiting factor for grazer growth. Our results highlight the role of feedback effects and the importance of long-term experiments in the study of foodweb interactions.
Subject(s)
Biofilms/growth & development , Chlorella vulgaris/growth & development , Ecosystem , Eutrophication , Microalgae/growth & development , Rivers/chemistry , Snails/physiology , Animals , Light , Nitrogen/metabolism , Phosphorus/metabolismABSTRACT
The authors reported a potential candidate methylated mud snail protein (MeMsp) as an effective and eco-friendly flocculant to treat the high turbidity wastewater. MeMsp was obtained by extraction of mud snail protein (Msp) through isoelectric precipitation (PSC-IP) and then methylated via the esterification with side-chain carboxyl. Structural characterization of FT-IR, zeta potential and elemental analysis were carried out and further confirmed the successful of the methylation. Flocculation experiments with kaolin suspension simulated wastewater indicated that MeMsp-24 displayed more excellent flocculation efficiency at a low dosage. At the optimum dosage 27 mg/L, the maximum clarification efficiency of MeMsp-24 was 97.46% under pH 7.0. Furthermore, MeMsp-24 exhibited a wide flocculation window in the pH range 1.0-9.0, and faster sedimentation velocity and larger flocs size. In addition, MeMsp-24 exhibited 92.12% clarification efficiency in treating railway tunnel construction effluent. The flocculation kinetic and mechanism analysis revealed that the most effective particle collision occurred at the optimal dosage, with charge neutralization and adhesion playing irreplaceable roles in different environments, respectively. Therefore, through extraction and methylation modification, MeMsp could be a promising eco-friendly flocculant for high turbidity wastewater treatment.
Subject(s)
Water Purification , Animals , Flocculation , Kaolin , Snails , Spectroscopy, Fourier Transform InfraredABSTRACT
OBJECTIVE: To assess the molluscicidal activity of the of Bacillus Y6 strain against Oncomelania hupensis in laboratory, and to preliminarily investigate its mechanisms of molluscicidal actions. METHODS: Biological identification of the Y6 strain was performed based on analysis of its morphological and physiochemical features and homology analysis of the 16S rDNA gene sequence. Bacillus Y6 suspensions were formulated at concentrations of 0.005, 0.010 g/mL and 0.015 g/mL, and the molluscicidal activity of Bacillus Y6 suspensions against O. hupensis was tested in laboratory using the immersion method. In addition, the Bacillus Y6 content and glycogen content were detected in O. hupensis following exposure to Bacillus Y6 suspensions to preliminarily explore the molluscicidal mechanism of the Bacillus Y6 strain against O. hupensis. RESULTS: The colony of the Bacillus Y6 strain appeared non-transparent milky white, and mycoderma was produced on the surface of the nutrient agar liquid medium. The Y6 stain was Gram positive and rod-shaped, and the endospore was located at the center of the Bacillus Y6 strain and appeared an achromatic, transparent and refractive body, which was encapsulated by the Y6 strain. The Y6 strain was positive for the lecithinase test, and the 16S rDNA gene sequence showed a 100% homology with those of multiple B. velezensisis strains, B. amyloliquefaciens and B. subtilis. The Y6 strain was therefore identified as B. velezensisis. Following immersion in the Bacillus Y6 suspensions at concentrations of 0.005, 0.010 g/mL and 0.015 g/mL for 24, 48 h and 72 h, the mortality rates of Oncomelania snails were 28.3%, 31.7% and 81.6%, 43.3%, 58.3% and 93.3%, and 63.3%, 78.3% and 98.3%, respectively. The molluscicidal activity of the Bacillus Y6 suspensions increased with the suspension concentration and duration of immersion. Microscopy and colony counting revealed the highest Y6 content in dead snails and the lowest in living snails following immersion in Bacillus Y6 suspensions, and the mean glycogen contents were (0.68 ± 0.06), (1.09 ± 0.16) µg/mg and (2.56 ± 0.32) µg/mg in the soft tissues of dead, dying and living snails following immersion in Bacillus Y6 suspensions (F = 59.519, P < 0.05), and the mean glycogen content was significantly higher in living snails than in dead (t = 14.073, P < 0.05) and dying snails (t = 10.027, P < 0.05), while the mean glycogen content was significantly higher in dying snails than in dead snails (t = 5.983, P < 0.05). CONCLUSIONS: The B. velezensisis Y6 strain shows a high molluscicidal activity against O. hupensis snails, and its invasion may cause glycogen metabolism disorders, leading to snail death.
Subject(s)
Bacillus , Molluscacides , Animals , Plant Extracts , SnailsABSTRACT
BACKGROUND: Schistosomiasis japonica is a chronic parasitic disease that seriously harms people's health. Oncomelania hupensis is the only intermediate host of Schistosoma japonicum. The micro-environmental factors surrounding the snail have a great impact on the survival, growth and reproduction of O. hupensis, but there are few relevant systematic analyses until the present. This scoping review aims to identify and summarize the micro-environmental factors that greatly affect O. hupensis, and to find gaps in research thus to provide directions for future in-depth studies. MAIN BODY: This scoping review searched databases with search terms of the combinations of "Micro(-)environment", "Oncomelania" and their expanded aspects. A total of 133 original articles were recruited. Predefined data fields were extracted including research methods, influencing factors, and their effects on O. hupensis. Most studies focused on vegetation factors (54.1%), and other factors noted were soil composition (27.8%), water environmental factors (24.1%), and predator (3.0%), respectively. The factors with positive impacts included water level, pH value, soil temperature, soil humidity, the coverage and height of vegetation at suitable levels. This could provide more detailed information for O. hupensis habitat identification and prediction. The factors with negative impacts included plant extracts, snail control and disease prevention forests, and microorganisms with molluscicidal activities. It revealed a potential application as ecological molluscicides in the future. Factors such as physico-chemical properties of water, soil chemistry showed a gap in scientific studies, thus required further extensive research. CONCLUSIONS: Micro-environmental factors including water quality, soil composition as well as the technology and application of biomolluscicides (plant extracts and microorganisms) deserve more attention. Relative study findings on micro-environment have good potentials in snail control applications. Further studies should be implemented to investigate the impact of micro-environmental factors on snails and close the research gaps.
Subject(s)
Schistosoma japonicum , Schistosomiasis japonica , Animals , China , Ecosystem , Humans , Reproduction , Schistosomiasis japonica/prevention & control , SnailsABSTRACT
Lantana camara is a troublesome invasive plant introduced to many tropical regions, including Southeast Asia. However, the plant does hold promise as a source of essential oils that may be explored for potential use. Fresh water snails such as Pomacea canaliculata, Gyraulus convexiusculus, and Tarebia granifera can be problematic agricultural pests as well as hosts for parasitic worms. Aedes and Culex mosquitoes are notorious vectors of numerous viral pathogens. Control of these vectors is of utmost importance. In this work, the essential oil compositions, molluscicidal, and mosquito larvicidal activities of four collections of L. camara from north-central Vietnam have been investigated. The sesquiterpene-rich L. camara essential oils showed wide variation in their compositions, not only compared to essential oils from other geographical locations (at least six possible chemotypes), but also between the four samples from Vietnam. L. camara essential oils showed molluscicidal activities comparable to the positive control, tea saponin, as well as other botanical agents. The median lethal concentrations (LC50 ) against the snails were 23.6-40.2â µg/mL (P. canaliculata), 7.9-29.6â µg/mL (G. convexiusculus), and 15.0-29.6â µg/mL (T. granifera). The essential oils showed good mosquito larvicidal activities with 24-h LC50 values of 15.1-29.0â µg/mL, 26.4-53.8â µg/mL, and 20.8-59.3â µg/mL against Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus, respectively. The essential oils were more toxic to snails and mosquito larvae than they were to the non-target water bug, Diplonychus rusticus (24-h LC50 =103.7-162.5â µg/mL). Sesquiterpene components of the essential oils may be acting as acetylcholinesterase (AChE) inhibitors. These results suggest that the invasive plant, L. camara, may be a renewable botanical pesticidal agent.
Subject(s)
Insecticides/pharmacology , Lantana/chemistry , Molluscacides/pharmacology , Mosquito Vectors/drug effects , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Snails/drug effects , Animals , Dose-Response Relationship, Drug , Insecticides/chemistry , Insecticides/isolation & purification , Models, Molecular , Molluscacides/chemistry , Molluscacides/isolation & purification , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Plant Extracts/chemistry , Plant Extracts/isolation & purification , VietnamABSTRACT
When oil is spilled into the environment its toxicity is affected by abiotic conditions. The cumulative and interactive stressors of chemical contaminants and environmental factors are especially relevant in estuaries where tidal fluctuations cause wide variability in salinity, temperature, and ultraviolet (UV) light penetration, which is an important modifying factor for polycyclic aromatic hydrocarbon (PAH) toxicity. Characterizing the interactions of multiple stressors on oil toxicity will improve prediction of environmental impacts under various spill scenarios. This study examined changes in crude oil toxicity with temperature, salinity, and UV light. Oil exposures included high-energy, water-accommodated fractions (HEWAFs) and thin oil sheens. Larval (24-48 h post hatch) estuarine species representing different trophic levels and habitats were evaluated. Mean 96 h LC50 values for oil prepared as a HEWAF and tested under standard conditions (20 ppt, 25 °C, No-UV) were 62.5 µg/L tPAH50 (mud snails), 198.5 µg/L (grass shrimp), and 774.5 µg/L (sheepshead minnows). Thin oil sheen 96 h LC50 values were 5.3 µg/L tPAH50 (mud snails), 14.7 µg/L (grass shrimp), and 22.0 µg/L (sheepshead minnows) under standard conditions. UV light significantly increased the toxicity of oil in all species tested. Oil toxicity also was greater under elevated temperature and lower salinity. Multi-stressor (oil combined with either increased temperature, decreased salinity, or both) LC50 values were reduced to 3 µg/L tPAH50 for HEWAFs and < 1.0 µg/L tPAH50 for thin oil sheens. Environmental conditions at the time of an oil spill will significantly influence oil toxicity and organismal response and should be taken into consideration in toxicity testing and oil spill damage assessments.
Subject(s)
Larva/drug effects , Petroleum Pollution , Petroleum/toxicity , Water Pollutants, Chemical/toxicity , Animals , Crustacea , Killifishes/physiology , Lethal Dose 50 , Louisiana , Polycyclic Aromatic Hydrocarbons/toxicity , Salinity , Snails/drug effects , Temperature , Toxicity Tests , Ultraviolet RaysABSTRACT
Burns are a global public health problem and the treatment of burn wounds is a major medical and economic issue. White jade snails (Achatina fulica) are now widely distributed in Asia, and they have been used to treat burns in folk medicine of China. In this study, the glycoproteins from white jade snails were investigated and their effect on burn healing was evaluated by a mouse burn model. The results showed that the snail mucus was mainly composed of proteins and polysaccharides, and it had good adhesion. The main component of snail mucus was glycoprotein from the results of DEAE Sepharose FF ion exchange chromatography. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging effect of 1 mg/mL snail mucus reached 13.77%. The wound healing rate of the snail mucus group was higher than that of the control group (p < 0.0001). Histopathological results showed that mice in the snail mucus group had a faster healing than that of the control group. The biochemical analysis was in agreement with the histopathological findings. These results suggested that glycoproteins from snail mucus showed effective wound healing activities in the skin of experimentally burned mice.
Subject(s)
Burns/drug therapy , Glycoproteins/pharmacology , Snails/metabolism , Animals , Burns/metabolism , Chromatography, Ion Exchange/methods , Female , Gastropoda/metabolism , Glycoproteins/isolation & purification , Medicine, Traditional/methods , Mice , Mucus/chemistry , Polysaccharides/metabolism , Wound Healing/physiologyABSTRACT
Schistosomiasis, or "snail fever", is a parasitic disease affecting over 200 million people worldwide. People become infected when exposed to water containing particular species of freshwater snails. Habitats for such snails can be mapped using lightweight, inexpensive and field-deployable consumer-grade Unmanned Aerial Vehicles (UAVs), also known as drones. Drones can obtain imagery in remote areas with poor satellite imagery. An unexpected outcome of using drones is public engagement. Whereas sampling snails exposes field technicians to infection risk and might disturb locals who are also using the water site, drones are novel and fun to watch, attracting crowds that can be educated about the infection risk.
Subject(s)
Communicable Diseases/epidemiology , Schistosomiasis/epidemiology , Snails/parasitology , Animals , Ecosystem , Humans , Remote Sensing Technology , Satellite ImageryABSTRACT
Terrestrial gastropods express metal-selective metallothioneins (MTs) by which they handle metal ions such as Zn2+ , Cd2+ , and Cu+ /Cu2+ through separate metabolic pathways. At the same time, they depend on the availability of sufficient amounts of Cu as an essential constituent of their respiratory protein, hemocyanin (Hc). It was, therefore, suggested that in snails Cu-dependent MT and Hc pathways might be metabolically connected. In fact, the Cu-specific snail MT (CuMT) is exclusively expressed in rhogocytes, a particular molluscan cell type present in the hemocoel and connective tissues. Snail rhogocytes are also the sites of Hc synthesis. In the present study, possible interactions between the metal-regulatory and detoxifying activity of MTs and the Cu demand of Hc isoforms was explored in the edible snail Cornu aspersum, one of the most common European helicid land snails. This species possesses CdMT and CuMT isoforms involved in metal-selective physiological tasks. In addition, C. aspersum expresses three different Hc isoforms (CaH ÉD, CaH ÉN, CaH ß). We have examined the effect of Cd2+ and Cu2+ exposure on metal accumulation in the midgut gland and mantle of C. aspersum, testing the impact of these metals on transcriptional upregulation of CdMT, CuMT, and the three Hc genes in the two organs. We found that the CuMT and CaH ÉD genes exhibit an organ-specific transcriptional upregulation in the midgut gland of Cu-exposed snails. These results are discussed in view of possible interrelationships between the metal-selective activity of snail MT isoforms and the synthesis and metabolism of Hc isoforms.
Subject(s)
Cadmium/pharmacology , Copper/pharmacology , Hemocyanins/metabolism , Snails/drug effects , Animals , Base Sequence , Cadmium/metabolism , Copper/metabolism , DNA, Complementary , Gene Expression Regulation/drug effects , Hemocyanins/genetics , Metallothionein , Metals/metabolism , Metals/pharmacology , Snails/metabolismABSTRACT
Metallothioneins (MTs) are a diverse group of proteins responsible for the control of metal homeostasis and detoxification. To investigate the impact that environmental conditions might have had on the metal-binding abilities of these proteins, we have characterized the MTs from the apple snail Pomacea bridgesii, a gastropod species belonging to the class of Caenogastropoda with an amphibious lifestyle facing diverse situations of metal bioavailability. P. bridgesii has two structurally divergent MTs, named PbrMT1 and PbrMT2, that are longer than other gastropod MTs due to the presence of extra sequence motifs and metal-binding domains. We have characterized the Zn(II), Cd(II), and Cu(I) binding abilities of these two MTs after their heterologous expression in E. coli. Our results have revealed that despite their structural differences, both MTs share an unspecific metal-binding character, and a great ability to cope with elevated amounts of different metal ions. Our analyses have also revealed slight divergences in their metal-binding features: PbrMT1 shows a more pronounced Zn(II)-thionein character than PbrMT2, while the latter has a stronger Cu(I)-thionein character. The characterization of these two unconventional PbrMTs supports the loss of the metal-binding specificity during the evolution of the MTs of the Ampullariid family, and further suggests an evolutionary link of this loss with the adaptation of these gastropod lineages to metal-poor freshwater habitats.