Insecticidal properties of extracts and phytochemicals isolated from three Egyptian plants against Culex pipiens

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
SA Abdelgaleil ◽  
T Suganuma ◽  
K Kitahara ◽  
M Fujii
Keyword(s):  
Culex Pipiens

Fine Structure of the Malpighian Tubules of the Mosquito, Culex pipiens

1971 ◽  
Vol 29 ◽  
pp. 402-403
Author(s):  
Brendan Clifford
Keyword(s):  
Fine Structure ◽  
Culex Pipiens ◽  
Stellate Cell ◽  
Malpighian Tubule ◽  
Cell Types ◽  
Instar Larva ◽  
Malpighian Tubules ◽  
Calliphora Erythrocephala ◽  
Distinct Cell ◽  
Basal Plasma

An ultrastructural investigation of the Malpighian tubules of the fourth instar larva of Culex pipiens was undertaken as part of a continuing study of the fine structure of transport epithelia.Each of the five Malpighian tubules was found to be morphologically identical and regionally undifferentiated. Two distinct cell types, the primary and stellate, were found intermingled along the length of each tubule. The ultrastructure of the stellate cell was previously described in the Malpighian tubule of the blowfly, Calliphora erythrocephala by Berridge and Oschman.The basal plasma membrane of the primary cell is extremely irregular, giving rise to a complex interconnecting network of basal channels. The compartments of cytoplasm entrapped within this system of basal infoldings contain mitochondria, free ribosomes, and small amounts of rough endoplasmic reticulum. The mitochondria are distinctive in that the cristae run parallel to the long axis of the organelle.

The Scientific Basis for the Prevention of Zooanthroponoze Vector-Borne Diseases Spread by Parasitic Arthropods of the Center of the East European Plain

2020 ◽  
Vol 14 (1) ◽  
pp. 81-88
Author(s):  
Fedor I. Vasilevich ◽  
Anna M. Nikanorova
Keyword(s):  
Mathematical Models ◽  
Culex Pipiens ◽  
Preventive Measures ◽  
Mosquito Species ◽  
Natural Habitat ◽  
Piperonyl Butoxide ◽  
East European Plain ◽  
Vector Borne Diseases ◽  
Vector Borne ◽  
Kaluga Region

The purpose of the research is development of preventive measures against zooanthroponoze vector-borne diseases spread by parasitic arthropods in the Kaluga Region. Materials and methods. The subject of the research was Ixodidae, mosquitoes, and small mammals inhabiting the Kaluga Region. The census of parasitic arthropods was carried out on the territory of all districts of the Kaluga Region and the city of Kaluga. Open natural habitat and human settlements were investigated. Weather conditions from 2013 to 2018 were also taken into account. For the purposes of the study, we used standard methods for capturing and counting arthropods and mouse-like rodents. In order to obtain mathematical models of small mammal populations, a full factorial experiment was conducted using the collected statistical data. In-process testing of the drug based on s-fenvalerate and piperonyl butoxide were carried out under the conditions of the agricultural collective farm “Niva” of the Kozelsky District, the Kaluga Region, and LLC “Angus Center of Genetics” of the Babyninsky District, the Kaluga Region. Results and discussion. In the Kaluga Region, two species of ixodic ticks are found, namely, Ixodes ricinus and Dermacentor reticulatus, which have two activity peaks. Mosquito may have 3-4 generations in a year in the Kaluga region. The most common mosquito species in the Kaluga Region are Aedes communis, Ae. (Och.) togoi and Ae. (Och.) diantaeus, Culex pipiens Culex Linnaeus, 1758 (Diptera, Culicidae) (Culex pipiens): Cx. pipiens f. pipiens L. (non-autogenic form) and Cx. p. f. molestus Fors. (autogenic form), which interbreed, and reproductively isolated in the Region. The developed mathematical models make it possible to quantify the risks of outbreaks of zooanthroponoze vector-borne diseases without the cost of field research, and allow for rational, timely and effective preventive measures. Medications based on s-fenvalerate and piperonyl butoxide and based on cyfluthrin showed high insecto-acaricidal efficacy and safety.

Estudio y evaluación de depredadores y bacterias entomopatógenas de Aedes aegypti (L.) y Culex pipiens (L.), como potenciales agentes de control

2010 ◽  
Author(s):  
◽  
María Cecilia Tranchida
Keyword(s):  
Aedes Aegypti ◽  
Culex Pipiens ◽  
Principal Vector ◽  
La Plata

Aedes aegypti y Culex pipiens se encuentran entre las principales especies de mosquitos vectores de enfermedades a nivel mundial. Ambas, son de gran importancia sanitaria en la Argentina. Aedes aegypti, es el principal vector del dengue y la fiebre amarilla. Está presente en la Argentina desde 1983, cuando fue confirmada su reemergencia en nuestro país. A partir de entonces comenzaron a detectarse casos de dengue hasta que el último brote de esta enfermedad en 2009 produjo 24.720 casos autóctonos confirmados por la OPS a nivel nacional. Culex pipiens es vector de algunas filariasis, y de importantes arbovirosis como la ocasionada por el virus del Nilo Occidental. La actividad vectorial de este mosquito se ve incrementada en zonas donde la densidad de zanjas de desagüe domiciliario es elevada, ya que este tipo de ambiente constituye un lugar propicio para su desarrollo. De su importancia sanitaria nace la necesidad de controlar su actividad vectorial, manteniendo las poblaciones en bajas densidades. El objetivo de este trabajo fue desarrollar estrategias para el control de A. aegypti y C. pipiens, basadas en métodos biológicos, eficaces, permanentes y seguros para el ambiente, mediante el empleo de enemigos naturales presentes en las poblaciones de ambas especies. En este trabajo, fueron evaluados copépodos, turbelarios y peces como depredadores; y bacterias entomopatógenas (α-protobacterias y bacterias esporulantes). El estudio de los copépodos, tuvo como objetivo identificar a la comunidad de copépodos larvívoros que se desarrolla en los criaderos de mosquitos, ubicados en los alrededores de la ciudad de La Plata, para identificar nuevas especies capaces de depredar mosquitos que habitan recipientes artificiales (A. aegypti y C. pipiens). La diversidad de copépodos larvívoros fue mayor en los cuerpos de agua permanentes. Acanthocyclops robustus, Diacyclops uruguayensis, Macrocyclops albidus y Mesocyclops longisetus fueron seleccionados por su capacidad depredadora. En el laboratorio fueron evaluadas: la capacidad de depredación de ambos sexos y diferentes estadios, preferencia de especie presa, y la tasa de depredación diaria. Las hembras de estas especies de copépodos presentaron mayor capacidad depredadora. No se detectó preferencia de los copépodos hacia ninguna de las especies de mosquitos. También se evaluó la tolerancia a la desecación y la capacidad de vivir en el agua que se acumula en los recipientes artificiales. Diacyclops uruguayensis y A. robustus sobrevivieron en las condiciones de sequía ensayadas en este estudio, pero D. uruguayensis mostró una menor supervivencia en el agua de recipientes artificiales. Macrocyclops albidus no sobrevivió en condiciones de sequía ni toleró el agua extraída de los recipientes artificiales. La supervivencia de M. longisetus ante estas condiciones, fue reducida. Se concluyó que las especies D. uruguayensis y A. robustus podrían ser buenos candidatos para el control de especies de mosquitos que crían en recipientes artificiales.

scholarly journals MiR-4448 is involved in deltamethrin resistance by targeting CYP4H31 in Culex pipiens pallens

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Xixi Li ◽  
Shengli Hu ◽  
Haitao Yin ◽  
Hongbo Zhang ◽  
Dan Zhou ◽  
...  
Keyword(s):  
Culex Pipiens ◽  
Oral Feeding ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Culex Pipiens Pallens ◽  
Deltamethrin Resistance ◽  
Regulatory Functions ◽  
Pipiens Pallens

Abstract Background Culex pipiens (Cx. pipiens) complex, which acts as a vector of viruses and is widespread and abundant worldwide, including West Nile virus, Japanese encephalitis virus, and Sindbis virus, can cause serious vector-borne diseases affecting human health. Unfortunately, mosquitoes have developed deltamethrin resistance because of its long-term overuse, representing a major challenge to mosquito control. Understanding the molecular regulatory mechanisms of resistance is vital to control mosquitoes. MicroRNAs (miRNAs) are short non-coding RNAs that have been demonstrated to be important regulators of gene expression across a wide variety of organisms, which might function in mosquito deltamethrin resistance. In the present study, we aimed to investigate the regulatory functions of miR-4448 and CYP4H31 in the formation of insecticidal resistance in mosquito Culex pipiens pallens. Methods We used quantitative real-time reverse transcription PCR to measure miR-4448 and CYP4H31 (encoding a cytochrome P450) expression levels. The regulatory functions of miR-4448 and CYP4H31 were assessed using dual-luciferase reporter assays. Then, oral feeding, RNA interference, and the American Centers for Disease Control and Prevention bottle bioassay were used to determine miR-4448’s association with deltamethrin resistance by targeting CYP4H31in vivo. Cell Counting Kit-8 (CCK-8) was also used to detect the viability of pIB/V5-His-CYP4H31-transfected C6/36 cells after deltamethrin treatment in vitro. Results MiR-4448 was downregulated in the deltamethrin-resistant strain (DR strain), whereas CYP4H31 was downregulated in deltamethrin-susceptible strain. CYP4H31 expression was downregulated by miR-4448 recognizing and binding to its 3′ untranslated region. Functional verification experiments showed that miR-4448 overexpression resulted in lower expression of CYP4H31. The mortality of miR-4448 mimic-injected DR strain mosquitoes was higher than that of the controls. CCK-8 assays showed that CYP4H31 decreased cellular resistance to deltamethrin in vitro and the mortality of the DR strain increased when CYP4H31 was knocked down in vivo. Conclusions In mosquitoes, miR-4448 participates in deltamethrin resistance by targeting CYP4H31. The results of the present study increase our understanding of deltamethrin resistance mechanisms.

scholarly journals Gonoactivity of Culex (Culex) (Diptera: Culicidae) Mosquitoes During Winter in Temperate Argentina

2021 ◽  
Author(s):  
María Florencia Branda ◽  
Magdalena Laurito ◽  
Andrés Mario Visintin ◽  
Walter Ricardo Almirón
Keyword(s):  
Developmental Stage ◽  
Culex Quinquefasciatus ◽  
Culex Pipiens ◽  
Life Cycles ◽  
Morphological Identification ◽  
Dry Ice ◽  
Culex Pipiens Pipiens ◽  
Host Seeking ◽  
Baited Traps ◽  
The City

Abstract The subgenus Culex L. includes species involved in summer–autumn arbovirus transmission but studies during winter are scarce in temperate Argentina. Female specimens were collected host-seeking at dry-ice-baited traps during autumn–winter–spring at two sites in Córdoba City during 2016 and 2017. The specimens were morphologically identified and dissected to determine the follicular developmental stage (gonotrophic activity). Females with advanced follicular stages (≥III) were subjected to molecular procedures to confirm or re-identify previous morphological identification. Five species (Culex apicinus Philippi (Diptera: Culicidae), Culex dolosus (Lynch-Arribálzaga) (Diptera: Culicidae), Culex maxi Dyar (Diptera: Culicidae), Culex pipiens pipiens L. (Diptera: Culicidae), and Culex quinquefasciatus Say (Diptera: Culicidae)) were collected and found gonoactive during winter; showing that a high proportion of Culex (Culex) females remain reproductively active during the unfavorable season for mosquito populations. Among them, it is worth noting the collection of Cx. quinquefasciatus, vector of the St. Louis encephalitis virus (endemic in the city), a specimen of Cx. p. pipiens, and a hybrid of Cx. p. pipiens/Cx. quinquefasciatus (during autumn). The study of this community during winter should continue because a high gonoactive female proportion with advanced follicular stages was found: 29.12 and 13.07% in 2016 and 2017, respectively. Local studies such as this one provide evidence about ornithophilic Culex species with active year-round life cycles, species that could favor arbovirus overwintering.

scholarly journals Characterization of phospholipase B of Culex pipiens fatigans

1969 ◽  
Vol 10 (6) ◽  
pp. 636-641
Author(s):  
R. Hanumantha Rao ◽  
D. Subrahmanyam
Keyword(s):  
Culex Pipiens ◽  
Culex Pipiens Fatigans ◽  
Phospholipase B
Sign in / Sign up

Export Citation Format

Share Document