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1.
Int J Med Mushrooms ; 26(3): 41-53, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505902

RESUMO

The worldwide scientific community is well aware that mosquitoes are the sole agents responsible for transmitting various dreadful diseases and critical illnesses caused by vector-borne pathogens. The primary objective of this current research was to evaluate the effectiveness of methanol extract from Tricholoma equestre mushroom in controlling the early life stages of Culex quinquefasciatus Say, Anopheles stephensi Liston, and Aedes aegypti (Linnaeus in Hasselquist) mosquitoes. The larvae, pupae and eggs of these mosquitoes were exposed to four different concentrations (62.5 to 500 ppm). After 120 h of treatment, the methanol extract of T. equestre exhibited ovicidal activity ranging from 66% to 80% against the eggs of the treated mosquitoes. It also demonstrated promising larvicidal and pupicidal activity with LC50 values of 216-300 and 230-309 ppm against the early life stages of all three mosquito species. Extensive toxicity studies revealed that the methanol extract from T. equestre had no harmful effects on non-target organisms. The suitability index (SI) or predator safety factor (PSF) indicated that the methanol extract did not harm Poecilia reticulata Peters 1859, (predatory fish), Gambusia affinis S. F. Baird & Girard 1853, dragonfly nymph and Diplonychus indicus Venkatesan & Rao 1871 (water-bug). Gas chromatography-mass spectrometry (GCMS) analysis identified key compounds, including 3-butenenitrile, 2-methyl-(25.319%); 1-butanol, 2-nitro-(18.87%) and oxalic acid, heptyl propyl ester (21.82%) which may be responsible for the observed activity. Furthermore, the formulation based on the methanol extract demonstrated similar effectiveness against all treated mosquitoes at the laboratory level and was found to be non-toxic to mosquito predators. This groundbreaking research represents the first confirmation that methanol extract from T. equestre could be effectively employed in preventing mosquito-borne diseases through mosquito population control programs.


Assuntos
Aedes , Agaricales , Anopheles , Culex , Inseticidas , Odonatos , Animais , Metanol/farmacologia , Mosquitos Vetores , Inseticidas/farmacologia , Inseticidas/química , Extratos Vegetais/química , Larva , Folhas de Planta/química
2.
Exp Parasitol ; 258: 108709, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301765

RESUMO

Mosquitoes stand out as the most perilous and impactful vectors on a global scale, transmitting a multitude of infectious diseases to both humans and other animals. The primary objective of the current research was to assess the effectiveness of EOs from Ocimum tenuiflorum L. and Ocimum americanum L. in controlling Anopheles stephensi Liston. Culex quinquefasciatus Say and Aedes aegypti L. mosquitoes. The larvae, pupae and eggs of the mosquitoes were exposed to four different concentrations (6.25-50 ppm). The tested EOs resulted in >99-100 % mortality at 120 h for the eggs of all examined mosquito species. It also showed robust larvicidal and pupicidal activity with LC50 and LC90 values of 17-39, 23-60 ppm and 46-220, and 73-412 ppm against Aedes, Culex and Anopheles mosquito species, respectively, at 24 h of treatment. The Suitability Index or Predator Safety Factor demonstrated that the EOs extracted from O. tenuiflorum L. and O. americanum L. did not cause harm to P. reticulata, D. indicus (water bug), G. affinis and nymph (dragonfly). GC-MS analysis identified the major probable constituents of the oil, including Phenol, 2-Methoxy-4-(1-Propenyl)- (28.29 %); 1-Methyl-3-(1'-Methylcyclopropyl) Cyclopentene (46.46 %); (E,E,E)-3,7,11,15-Tetramethylhexadeca-1,3,6,10,14-Pentaene (18.91 %) and 1,3-Isobenzofurandione, 3a,4,7,7a-Tetrahydro-4,7-Dimethyl (33.02 %). These constituents may play a significant role in the mosquitocidal activity of the oil. The same results were identified in the formulation prepared from the EOs. This marks the first report confirming the successful utilization of EOs derived from O. tenuiflorum L. and O. americanum L. in mosquito population control initiatives.


Assuntos
Aedes , Anopheles , Culex , Inseticidas , Ocimum , Odonatos , Óleos Voláteis , Animais , Humanos , Óleos Voláteis/farmacologia , Óleos Voláteis/análise , Ocimum/química , Ocimum sanctum , Mosquitos Vetores , Inseticidas/análise , Larva , Extratos Vegetais/química , Folhas de Planta/química
3.
J Theor Biol ; 494: 110237, 2020 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-32151621

RESUMO

There are many marine animals that employ a form of jet propulsion to move through the water, often creating the jets by expanding and collapsing internal fluid cavities. Due to the unsteady nature of this form of locomotion and complex body/nozzle geometries, standard modeling techniques prove insufficient at capturing internal pressure dynamics, and hence swimming forces. This issue has been resolved with a novel technique for predicting the pressure inside deformable jet producing cavities (M. Krieg and K. Mohseni, J. Fluid Mech., 769, 2015), which is derived from evolution of the surrounding fluid circulation. However, this model was only validated for an engineered jet thruster with simple geometry and relatively high Reynolds number (Re) jets. The purpose of this manuscript is twofold: (i) to demonstrate how the circulation based pressure model can be used to analyze different animal body motions as they relate to propulsive output, for multiple species of jetting animals, (ii) and to quantitatively validate the pressure modeling for biological jetting organisms (typically characterized by complicated cavity geometry and low/intermediate Re flows). Using jellyfish (Sarsia tubulosa) as an example, we show that the pressure model is insensitive to complex cavity geometry, and can be applied to lower Re swimming. By breaking down the swimming behavior of the jellyfish, as well as that of squid and dragonfly larvae, according to circulation generating mechanisms, we demonstrate that the body motions of Sarsia tubulosa are optimized for acceleration at the beginning of pulsation as a survival response. Whereas towards the end of jetting, the velar morphology is adjusted to decrease the energetic cost. Similarly, we show that mantle collapse rates in squid maximize propulsive efficiency. Finally, we observe that the hindgut geometry of dragonfly larvae minimizes the work required to refill the cavity. Date Received: 10-18-2019, Date Accepted: 99-99-9999 *kriegmw@hawaii.edu, UHM Ocean and Res Eng, 2540 Dole St, Honolulu, HI 96822.


Assuntos
Organismos Aquáticos , Decapodiformes , Modelos Biológicos , Cifozoários , Natação , Animais , Fenômenos Biomecânicos , Decapodiformes/fisiologia , Larva/anatomia & histologia , Larva/fisiologia , Odonatos/fisiologia , Pressão , Cifozoários/fisiologia
4.
Chemosphere ; 243: 125369, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31765902

RESUMO

To make more realistic predictions about the current and future effects of pesticides, we need to better understand physiological mechanisms associated with the widespread higher toxicity of many pesticides under increasing mean temperatures and daily temperature fluctuations (DTFs). One overlooked, yet insightful, mechanism are bioenergetic responses as these provide information about the balance between energy gains and costs. Therefore, we studied how the bioenergetic responses to the insecticide chlorpyrifos were affected by a higher mean temperature and a higher DTF in Ischnura elegans damselfly larvae. To quantify bioenergetic responses we measured energy availability (Ea), energy consumption (Ec) and total net energy budget (cellular energy allocation, CEA). Exposure to chlorpyrifos considerably reduced CEA values when a high mean temperature was combined with a high DTF (up to -18%). Notably, chlorpyrifos had little effect on CEA at a constant 20 °C, meaning that the bioenergetic impact of chlorpyrifos would have been underestimated if we had only tested under standard testing conditions. The chlorpyrifos-induced reductions in CEA under warming were driven by reductions in Ea (up to -16%, mainly through large reductions in sugar and fat contents) while Ec was unaffected by chlorpyrifos. Treatment groups with a lower CEA value showed a higher mortality and a lower growth rate, indicating bioenergetic responses are contributing to the higher toxicity of chlorpyrifos under warming. Our study highlights the importance of evaluating the effects of pesticides under an increase in both mean temperature and DTF to improve the ecological risk assessment of pesticides under global warming.


Assuntos
Odonatos/fisiologia , Praguicidas/toxicidade , Temperatura , Animais , Clorpirifos/toxicidade , Metabolismo Energético , Aquecimento Global , Temperatura Alta , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Odonatos/efeitos dos fármacos
5.
Exp Parasitol ; 204: 107719, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31255572

RESUMO

The present study was aimed to check the mosquitocidal activity of tiliamosine isolated from Tiliacora acuminata (Lam.) Hook. f. & Thom against immature stages of Culex quinquefasciatus. Eggs and larvae of Cx. quinquefasciatus were exposed to different concentrations of tiliamosine - 0.5, 1.0, 1.5 and 2.0 ppm - prepared using DMSO. The compound tiliamosine showed good larvicidal activity with LC50 and LC90 values of 1.13 and 2.85 ppm respectively, against third-instar larvae of Cx. quinquefasciatus at 24 h. In control, the larvae exhibited normal movement. Tiliamosine exhibited 91% ovicidal activity at 2.0 ppm concentration after 120 h post-treatment. Lowest concentration of tiliamosine (0.5 ppm) showed 19% egg mortality. Histopathology study of the compound-treated larvae showed serious damage on the larval midgut cells. The treated larvae showed restless movement which was different from that of the control larvae. The larvae exhibited malformation in development. The compound tiliamosine was harmless to non-target organisms P. reticulata and Dragon fly nymph at tested concentrations. The compound was highly active and inhibited AChE in a concentration-dependent manner. Computational analysis of the tiliamosine had strong interaction with AChE1 of Cx. quinquefasciatus. This report clearly suggests that the isolated compound can be used as an insecticide to control mosquito population and thus prevent the spread of vector-borne diseases.


Assuntos
Benzilisoquinolinas/farmacologia , Culex/efeitos dos fármacos , Inseticidas/farmacologia , Menispermaceae/química , Mosquitos Vetores/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Culex/crescimento & desenvolvimento , Filariose/prevenção & controle , Filariose/transmissão , Larva/efeitos dos fármacos , Dose Letal Mediana , Ligantes , Simulação de Acoplamento Molecular , Mosquitos Vetores/crescimento & desenvolvimento , Odonatos/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Poecilia
6.
Aquat Toxicol ; 212: 205-213, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31132738

RESUMO

Ignoring natural stressors such as predation risk may contribute to the failure of ecological risk assessment of pesticides to protect freshwater biodiversity. To better understand combined effects of multiple stressors, bioenergetic responses are important as these inform about the balance between energy input and consumption, and provide a unifying mechanism to integrate the impact of multiple stressors with different modes of action. We studied in Enallagma cyathigerum damselfly larvae the single and combined effects of exposure to the pesticide chlorpyrifos and predation risk on life history (survival and growth rate) and bioenergetic response variables at the organismal level (assimilation and conversion efficiency) and the cellular level (cellular energy allocation CEA, energy storage Ea, and energy consumption Ec). Chlorpyrifos exposure almost halved the survival of the damselfly larvae, while predation risk had no effect on survival. Both exposure to the pesticide and to predation risk reduced larval growth rates. This was caused by a reduced conversion efficiency under chlorpyrifos exposure, and by a reduced assimilation efficiency under predation risk. Both chlorpyrifos and predation risk reduced the CEA because of a decreased Ea, and for chlorpyrifos also an increased Ec. The lower Ea was driven by reductions in the fat and glycogen contents. Effects of the pesticide and predation risk were consistently additive and for most variables the strongest response was detected when both stressors were present. The absence of any synergisms may be explained by the high mortality and hypometabolism caused by the pesticide. Our results indicate that CEA can be a sensitive biomarker to evaluate effects of not only contaminants but also natural stressors, such as predation risk, and their combined impact on organisms.


Assuntos
Clorpirifos/toxicidade , Metabolismo Energético/efeitos dos fármacos , Odonatos/efeitos dos fármacos , Animais , Reação de Fuga/efeitos dos fármacos , Larva/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade
7.
Sci Rep ; 7(1): 1476, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28469188

RESUMO

The clade Triadophlebiomorpha represents a morphological 'link' between the Paleozoic griffenflies (Meganisoptera) and the modern taxa. Nevertheless they are relatively poorly known in the body structures and paleobiogeography. The Triassic dragonfly is extremely rare in China with only one previously recorded. A new family, Sinotriadophlebiidae Zheng, Nel et Zhang fam. nov., for the genus and species Sinotriadophlebia lini Zheng, Nel et Zhang gen. et sp. nov., is described from the Upper Triassic Baijiantan Formation of Xinjiang, northwestern China. It is the second Chinese Triassic odonatopteran and the second largest Mesozoic representative of this superorder in China. The discovery provides new information for the clade Triadophlebiomorpha during the Late Triassic and expands its distribution and diversity in Asia. The find reflects a close relationship between the two Triassic entomofaunas from Kyrgyzstan and the Junggar Basin, and provides a Carnian age constraint on the lowermost part of the Baijiantan Formation.


Assuntos
Odonatos/classificação , Filogenia , Asas de Animais/anatomia & histologia , Animais , China , Fósseis/história , História Antiga , Odonatos/anatomia & histologia , Odonatos/fisiologia , Filogeografia , Asas de Animais/fisiologia
8.
Homeopathy ; 105(1): 96-101, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26828004

RESUMO

BACKGROUND: Homeopathy is a form of alternative medicine in which uses highly diluted preparations that are believed to cause healthy people to exhibit symptoms similar to those exhibited by patients. The aim of this study was to investigate the effects of dragonfly (Anax imperator, Anax i.) on learning and memory in naive mice using the Morris water maze (MWM) test; moreover, the effects of dragonfly on MK-801-induced cognitive dysfunction were evaluated. METHODS: Male balb-c mice were treated with dragonfly (30C and 200C) or MK-801 (0.2 mg/kg) alone or concurrently (n = 10). Dragonfly (D) and MK-801 were administered subchronically for 6 days intraperitoneally 60 min and 30 min, respectively, before the daily performance of the MWM test. RESULTS: This study revealed that in the familiarization session and first session of the MWM test, Anax i. D30 significantly decreased escape latency compared to the control group, although MK-801, D30 and D200 significantly increased escape latency at the end of five acquisition sessions. Anax i. combined with dizocilpine maleate (MK-801) also significantly decreased escape latency in the familiarization session and first session of the MWM test, although this combination increased escape latency compared to the MK-801 alone group at the end of the test. Time spent in escape platform's quadrant in the probe trial significantly decreased while mean distance to platform significantly increased in MK-801, D30 and D200 groups. In the MWM test, Anax i. combined with MK-801 significantly decreased speed of the animals compared to the MK-801 alone group. General cell morphology was disturbed in the MK-801 group while D30 and D200 seemed to improve cell damage in the MK-801 group. CONCLUSIONS: These results suggest that the homeopathic Anax i. can impair learning acquisition and reference memory, and it has beneficial effects on disturbed cell morphology.


Assuntos
Homeopatia/métodos , Materia Medica/uso terapêutico , Odonatos/química , Animais , Relação Dose-Resposta a Droga , Hormônios de Inseto/efeitos adversos , Hormônios de Inseto/uso terapêutico , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/efeitos adversos , Oligopeptídeos/uso terapêutico , Ácido Pirrolidonocarboxílico/efeitos adversos , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/uso terapêutico
9.
Nat Prod Res ; 30(7): 826-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26284510

RESUMO

Aedes aegypti is a primary vector of dengue, a mosquito-borne viral disease infecting 50-100 million people every year. Here, we biosynthesised mosquitocidal silver nanoparticles (AgNP) using the aqueous leaf extract of Crotalaria verrucosa. The green synthesis of AgNP was studied by UV-vis spectroscopy, SEM, EDX and FTIR. C. verrucosa-synthesised AgNPs were toxic against A. aegypti larvae and pupae. LC50 of AgNP ranged from 3.496 ppm (I instar larvae) to 17.700 ppm (pupae). Furthermore, we evaluated the predatory efficiency of dragonfly nymphs, Brachydiplax sobrina, against II and III instar larvae of A. aegypti in an aquatic environment contaminated with ultra-low doses of AgNP. Under standard laboratory conditions, predation after 24 h was 87.5% (II) and 54.7% (III). In an AgNP-contaminated environment, predation was 91 and 75.5%, respectively. Overall, C. verrucosa-synthesised AgNP could be employed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of dragonfly nymphs.


Assuntos
Aedes , Crotalaria/química , Nanopartículas Metálicas/química , Odonatos/fisiologia , Extratos Vegetais/química , Comportamento Predatório , Animais , Vetores de Doenças , Inseticidas/química , Larva , Controle de Mosquitos , Folhas de Planta/química , Pupa , Prata/química
10.
Parasitol Res ; 114(12): 4645-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26337272

RESUMO

Malaria is a life-threatening disease caused by parasites transmitted to people and animals through the bites of infected mosquitoes. The employ of synthetic insecticides to control Anopheles populations leads to high operational costs, non-target effects, and induced resistance. Recently, plant-borne compounds have been proposed for efficient and rapid extracellular synthesis of mosquitocidal nanoparticles. However, their impact against predators of mosquito larvae has been poorly studied. In this study, we synthesized silver nanoparticles (AgNPs) using the Datura metel leaf extract as reducing and stabilizing agent. The biosynthesis of AgNPs was confirmed analyzing the excitation of surface plasmon resonance using ultraviolet-visible (UV-vis) spectroscopy. Scanning electron microscopy (SEM) showed the clustered and irregular shapes of AgNPs, with a mean size of 40-60 nm. The presence of silver was determined by energy-dispersive X-ray (EDX) spectroscopy. Fourier transform infrared (FTIR) spectroscopy analysis investigated the identity of secondary metabolites, which may be acting as AgNP capping agents. In laboratory, LC50 of D. metel extract against Anopheles stephensi ranged from 34.693 ppm (I instar larvae) to 81.500 ppm (pupae). LC50 of AgNP ranged from 2.969 ppm (I instar larvae) to 6.755 ppm (pupae). Under standard laboratory conditions, the predation efficiency of Anax immaculifrons nymphs after 24 h was 75.5 % (II instar larvae) and 53.5 % (III instar larvae). In AgNP-contaminated environment, predation rates were boosted to 95.5 and 78 %, respectively. Our results documented that D. metel-synthesized AgNP might be employed at rather low doses to reduce larval populations of malaria vectors, without detrimental effects on behavioral traits of young instars of the dragonfly Anax immaculifrons.


Assuntos
Anopheles/efeitos dos fármacos , Datura metel/química , Insetos Vetores/efeitos dos fármacos , Nanopartículas/metabolismo , Odonatos/fisiologia , Extratos Vegetais/química , Prata/metabolismo , Animais , Anopheles/fisiologia , Datura metel/metabolismo , Humanos , Insetos Vetores/fisiologia , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/fisiologia , Malária/transmissão , Nanopartículas/química , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Prata/farmacologia
11.
Homeopathy ; 104(1): 1-2, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25576264
12.
Zhongguo Zhen Jiu ; 25(1): 43-5, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16309156

RESUMO

Cheng's needling method like a dragonfly skimming the surface of the water is a needling method handed down in the family of chief TCM physician Cheng Zi-jun and it has been applied clinically for over one hundred years. It is a unique reinforcing-reducing method of acupuncture with simple and convenient manipulation and excellent therapeutic effect, which is created and gradually completed by Cheng's grandfather Mr. Cheng Jin-he on the basis of studying ancient various reinforcing-reducing methods. In the method, stimulating amount of acupuncture is introduced into reinforcing-reducing. Clinically, this method is used to treat various chronic pain syndromes with rapid effect.


Assuntos
Odonatos , Água , Acupuntura , Pontos de Acupuntura , Terapia por Acupuntura , Animais , China , História do Século XX , Humanos , Dor
13.
Artigo em Chinês | WPRIM | ID: wpr-258914

RESUMO

Cheng's needling method like a dragonfly skimming the surface of the water is a needling method handed down in the family of chief TCM physician Cheng Zi-jun and it has been applied clinically for over one hundred years. It is a unique reinforcing-reducing method of acupuncture with simple and convenient manipulation and excellent therapeutic effect, which is created and gradually completed by Cheng's grandfather Mr. Cheng Jin-he on the basis of studying ancient various reinforcing-reducing methods. In the method, stimulating amount of acupuncture is introduced into reinforcing-reducing. Clinically, this method is used to treat various chronic pain syndromes with rapid effect.


Assuntos
Animais , Humanos , Acupuntura , Pontos de Acupuntura , Terapia por Acupuntura , China , História do Século XX , Odonatos , Dor , Água
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