Ultrastructural characterization of hemocytes in the oriental cockroach Blatta orientalis (Blattodea: Blattidae)

Hemocytes are the cells that have a part in the insect's cellular and humoral immune systems. Yet, characterization of cells depends on light microscopic studies. In addition, using different names for cells generally may cause confusion. The present study aimed to characterize the morphological types of hemocytes in the oriental cockroach Blatta orientalis (Blattodea: Blattidae) (potential vectors of human allergies and asthma) using transmission electron microscopy. The study was conducted at the EGEMIKAL Analysis and Histology Laboratory of Ege University during 2019-2021. The circulating hemocytes in the ten individuals' adults (5-day old) of B. orientalis were characterized as four types based on their morphology. These were prohemocytes, plasmatocytes, granulocytes and oenocytes. The first three types of hemocytes were easily identified by their morphological features compared with other insect hemocyte types. This is the first report on the identification of oenocyte type cell in B. orientalis. The cell appeared large and elliptic. The nucleus was elongated, bi-nucleate and slightly opaque in cell. The cytoplasm contained several vacuoles filled with electron-dense materials. More comprehensive knowledge of hemocytes may help us understand better the cockroach cellular defense system

Demonstrating the general structure and cell types of the fat body in Blatta orientalis (Oriental Cockroach)

The fat body is a tissue that originates from mesoderm in insects. It consists of several cell types. The basic cell of the fat body is trophocyte. Glycogen, protein and lipid which are required for energy are stored in these cells. Mycetocyte, urocyte, chromotocyte and haemoglobin cells are the other cell types which originate from differentiated trophocytes. Of the cells found in cockroaches, mycetocytes contain an endosymbiont species of bacteria while urocytes are specialized cells for storing and discharging uric acid. Oenocyte, which is not the fat body cell type but associated with epidermis and the fat body cells, is also found in cockroaches. In this research, the fat body distribution was shown for the first time in three selected sections (thorax, beginning and end of abdomen) in all stages of Blatta orientalis (Linnaeus, 1758). In addition, the fat body cell types and distribution were determined by histological, histochemical and ultrastructural studies. As a result, trophocytes, mycetocytes, urocytes of the fat body and oenocytes which are related to the fat body were determined in B. orientalis. Also, it was revealed that the fat body content increased in the selected regions of the stages depending on the development. We hope that these findings will contribute to data about the fat body and give some directions to insecticide studies.Ege University Scientific Research Fund [FYL-2018-20133]Ege University Scientific Research Fund, Grant/Award Number: FYL-2018-2013

Evaluation of Pyrethroid Susceptibility in Culex pipiens of Northern Izmir Province, Turkey

WOS: 000455564000006PubMed ID: 30918906Background: Mosquitoes, being a nuisance species, are considered as one of the most important species in public health control programs due to their role as a vector in mosquito-borne diseases observed in humans and animals We evaluated the susceptibility status of Culex pipiens collected from northern Izmir, Turkey in 2011-16. Methods: Mosquito larvae, collected from three different locations in northern Izmir, were reared in the laboratory. Adult susceptibility bioassays were performed using the WHO insecticide-impregnated papers including deltamethrin 0.05%, permethrin 0.75%, alpha-cypermethrin 0.05% and cyfluthrin 0.15%. In addition, adult bioassays were performed after the pre-exposure to piperonyl butoxide (PBO) to determine the contribution of P450 detoxification enzymes to the phenotypic resistance. Results: In all of the three populations, high levels of resistance were observed (mortalities<63%) to all of the four pyrethroids. Different pyrethroids but with the same mode of action can exhibit significantly different phenotypic resistance in a single population. PBO bioassays also showed that P450 detoxification enzymes can have diverse effects on different pyrethroids. Conclusion: Using just one chemical in a class of insecticide can be misleading for resistance studies

Micro- and nano-encapsulation of limonene and permethrin for mosquito repellent finishing of cotton textiles

TURKOGLU, Gizem Ceylan/0000-0001-5809-0916; Erkan, Gokhan/0000-0002-2239-9556WOS: 000519929100004The aim of this study was to prepare mosquito repellent textiles. To compare bio-based and synthetic mosquito repellent agents, limonene and permethrin were encapsulated with ethyl cellulose shell. Coacervation was employed, which is a simple and reproducible method for the encapsulation with high production efficiency. Morphological assessment showed that the capsules had smooth surfaces and their shape was spherical. the homogenous size distribution of the capsules was supported by laser diffraction analysis. the capsules showed narrow size distribution and the mean particle size of the optimum formulations for limonene and permethrin was 1 and 1.3 mu m, respectively. the size of the produced capsules was considered suitable for textile applications. the FTIR spectra revealed the similarity of the chemical structure of capsules with shell material. Cotton fabrics were treated separately with limonene and permethrin capsules by padding method. the presence of capsules on the fabrics was determined after 20 washing cycles. Insecticide activity was evaluated against common house mosquitoes (Culex pipiens), with respect to cone bioassay of World Health Organization (WHO). Mosquitoes were tended to stay away from treated fabrics, and mortality rates of mosquitos were noted as 41% and 54% for limonene and permethrin, respectively. Although efficacy of fabrics decreased with increasing washing, the fabrics still showed repellency after 20 washing cycles. This study showed that the developed product might be used as an alternative to the other products in the market for avoiding mosquito-borne diseases

Reliability of Intravitreal Nepafenac in Rabbits

WOS: 000347391500008PubMed ID: 25285465Purpose: The purpose of this experiment was to investigate the possible toxic effects of Nepafenac, a nonsteroidal anti-inflammatory molecule, after its intravitreal application in various concentrations. Methods: Forty pigmented rabbits were randomly divided into 4 groups, each including 10 rabbits. The active ingredient Nepafenac was prepared to be applied in different doses, for intravitreal use. Under topical anesthesia, following pupil dilatation, 0.3, 0.5, 0.75, and 1.5 mg doses of Nepafenac was applied intravitreally into the right eye. In each rabbit, the right eye was considered to be the study group. Saline was injected intravitreally into the left eye of each rabbit, and these eyes were considered to be the control group. Immediately after the injection and at the 1st, 4th, and 8th weeks, fundus examination by indirect ophthalmoscopy and intraocular pressure measurement were conducted. Furthermore, electroretinographic (ERG) recordings were taken at the 4th and 8th weeks. At the end of the 8th week, eyes of the surviving 26 rabbits were enucleated, and then animals were sacrificed. Following necessary fixation procedures, histopathological investigations were conducted by using a light and electron microscope. In the histological cross sections, differences between the eyes with injection and the control group were evaluated, and total retinal thickness, inner nuclear layer thickness, and outer nuclear layer thickness were measured. Results: No pathology was found by clinical examination of either group. In the photopic and scotopic full-field ERG, conducted before the injection and in the 4th and 8th weeks after the injection, no statistically significant difference was determined between the study group and the control group. In the histological evaluation of the preparations, there were no statistically significant differences in the retina thickness of control and study groups. In the electron microscopic examinations, there were no toxicity findings in the eyes with injection. Conclusions: Our data show that intravitreal application of 0.3, 0.5, 0.75, and 1.5 mg doses of Nepafenac active substance is nontoxic to the rabbit retina.Ege University Research FoundationEge UniversitySupport for this study was provided by the Ege University Research Foundation