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Öğe Determination of Antimony Resistance Mechanism of Leishmania tropica Causing Cutaneous Leishmaniasis in Turkey(Ankara Microbiology Soc, 2020) Ozbilgin, Ahmet; Zeyrek, Fadile Yildiz; Guray, Melda Zeynep; Culha, Gulnaz; Akyar, Isin; Harman, Mehmet; Ozbel, YusufWorld Health Organization reported that approximately one billion people are at risk in endemic areas, one million cases of cutaneous leishmaniasis (CL) and approximately 300,000 cases of visceral leishmaniasis (VL) were reported per year in the last five years. The number of deaths due to VL is reported to be approximately 20,000 per year. Approximately 2500 cases/year have been reported as CL, caused by Leishmania tropica and Leishmania infantum, in Turkey. The significant increase observed in many cities mainly in the provinces of Mediterranean and Aegean regions in cases and foci in recent years, suggests that there may be an increase in this infections in the following years as well. In Turkey, the causative agent of CL is L.tropica and meglumine antimoniate is used in the treatment of CL. We aimed to determine antimony resistance genes specific for L.tropica by comparing the gene and protein expressions of antimony-resistant and non-resistant L.tropica strains. Ltropica isolates obtained from 3 CL patients without antimonate resistance from Aegean, Mediterranean and Southeastern regions of Turkey were provided to transform into 3 resistant isolates against meglumine antimony in the laboratory conditions. Gene expression alterations by microarray method; protein profiles by two-dimensional gel electrophoresis (2D-PAGE) and relevant proteins by MALDI-TOF/TOF MS of these isolates were accomplished and compared. L.tropica isolates from 10 CL patients who did not respond to antimony therapy were analyzed for resistance to antimonial compounds and quantitative real-time polymerase chain reaction was performed to detect the expression of genes responsible for resistance development. Moreover, differences in protein expression levels in isolates with and without antimony resistance were determined by comparing protein profiles and identification of proteins with different expression levels was carried out. Enolase, elongation factor-2, heat shock protein 70, tripanthione reductase, protein kinase C and metallo-peptidase proteins have been shown to play roles in L.tropica isolates developing resistance to antimonial compounds and similar expression changes have also been demonstrated in naturally resistant isolates from patients. In conclusion, it was revealed that L.tropica strains in our country may gain resistance to meglumine antimoniate in a short time. It is foreseen that if the patients living in our country or entering the country are treated inadequately and incompletely, there may be new, resistant leishmaniasis foci that may increase the number of resistant strains and cases rapidly.Öğe Distribution and altitudinal structuring of phlebotomine sand flies (Diptera: Psychodidae) in southern Anatolia, Turkey(Soc Vector Ecology, 2007) Simsek, Fatih M.; Alten, Bulent; Caglar, Selim S.; Ozbel, Yusuf; Aytekin, A. Murat; Kaynas, Sinan; Belen, AsliThe two Old World genera, Phlebotomus and Sergentomyia, were both recorded in southern Anatolia in Turkey. Phlebotomus species predominated and comprised about 93% of the entire collection (3,172 specimens). Out of the sixteen species identified, two belonged to the genus Sergentomyia: S. dentata and S. theodori. The remaining fourteen species in the genus Phlebotomus were grouped under four subgenera including some species that are elsewhere known to act as vectors of human cutaneous leishmaniasis. Most of the Phlebotomus were P tobbi (32.5%), but P papatasi, R transcaucasicus, P halepensis, P galilaeus, P sergenti, R syriacus, P neglectus, P simici, P alexandri, P similis, P jacusieli, R perfiliewi, and R brevis were also identified. There were two associations of sand fly fauna with altitudinal gradient; the first one at relatively higher altitudes and the second one at lower altitudes. The transition between these two assemblages was within the range of 8001,000 m. It is likely that Adana and Hatay provinces are transitional areas between western and eastern Anatolia. Mountains do not appear to be important geographical barriers for sand fly distribution. We also found that the proven vector R sergenti is a widely distributed species throughout southern Anatolia and this species, together with its closely related species R similis, shows sympatry in Konya Province.Öğe Faunistic Study of Sand Flies in Northern Cyprus(Univ Oradea Publ House, 2010) Demir, Samiye; Gocmen, Bayram; Ozbel, YusufA faunistic study of Phlebotominae (Diptera: Psychodidae) sand flies was carried out in northern Cyprus. A total of 12,517 sand flies (3,285 males and 9,232 females) was collected from 20 different localities in July and September 2004. Nine species belonging to genus Phlebotomus and 3 species of genus Sergentomyia were identified. Of these, the presence of the species Phlebotomus neglectus Tonnoir was reported for the first time in Cyprus, while P. jacusieli Theodor, P. kyreniae Theodor and P. economidesi Leger, Depaquit & Ferte were reported from the island for only the second time. However, P. mascitlii Grassi which was previously reported from southern Cyprus was not found in this study. The most abundant species for the overall northern Cyprus were P. galilaeus Theodor (60.88%), P. papatasi Scopoli (15.67%) and P. tobbi Adler & Theodor (12.47%). These three species account for 89.02% of all sand flies collected in this survey. Because of the previously reported parasitic diseases such as human and canine visceral leishmaniasis, cutaneous leishmaniasis and viral diseases such as sand fly fever, the distribution of the sand fly species belonging to genus Phlebotomus found in northern Cyprus and their vectorial status were discussed and the results were compared with previous reports.Öğe Leishmaniasis in Turkey: molecular characterization of Leishmania from human and canine clinical samples(Wiley-Blackwell Publishing, Inc, 2009) Toz, Seray Ozensoy; Nasereddin, Abedelmajeed; Ozbel, Yusuf; Ertabaklar, Hatice; Culha, Gulnaz; Sevil, Naser; Alkan, M. ZiyaHuman leishmaniasis, both visceral and cutaneous, and canine leishmaniasis have been reported in Turkey for centuries. However, the advent of new diagnostic tools during the last 30 years has led to the recognition that leishmaniasis is an important public health problem throughout the country. In most disease foci both canine and human leishmaniases exist together and identification of parasite species causing these diseases is a pre-requisite for understanding disease epidemiology. A total of 109 samples obtained from human and canine leishmaniasis cases were examined using internal transcribed spacer 1 PCR followed by restriction fragment length polymorphism analysis. Our results indicate that two species, Leishmania tropica and Leishmania infantum, are primarily responsible for cutaneous and visceral leishmaniasis, respectively, in Turkey. However, a new focus of human cutaneous leishmaniasis caused by L. infantum in Hatay region is described. This finding further stresses the importance of Leishmania species molecular characterization in prescribing appropriate therapy and understanding the disease's transmission in different endemic foci.Öğe A New Approach for Determining the Spatial Risk Levels for Visceral and Cutaneous Leishmaniasis related with the Distribution of Vector Species in Western Part of Turkey using Geographical Information Systems and Remote Sensing(Kafkas Univ, Veteriner Fakultesi Dergisi, 2012) Olgen, M. Kirami; Ozbel, Yusuf; Balcioglu, I. Cuneyt; Demir, Samiye; Simsek, Fatih; Toz, Seray Ozensoy; Ertabaklar, HaticeLeishmaniases are present in two clinical forms, as visceral and cutaneous, in Turkey showing a tendency of spreading throughout the country. The aim of the present study was to produce a new model for determining the spatial risk levels using the data in a selected study site in the western part of Turkey. The results of entomological studies in this leishmaniasis focus indicated the presence of suspected vector species Phlebotomus (Larroussius) tobbi and P (Larroussius) neglectus for the visceral, P (Paraphlebotomus) similis for cutaneous forms of the disease. The new risk model was developed based on univariate and multivariate binary logistic regression analyses of geographical variables as altitude, aspect, Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and Land Surface Temperature (LST) values related to the distribution of these three species. The results of the new model were used to produce the risk maps and the potential distribution areas of the incriminated vector species with the use of geographical technologies which allowed the identification of the leishmaniasis risk levels that may provide useful information to guide the control program interventions.Öğe Spatial distribution of phlebotomine sand flies in the Aydin Mountains and surroundings: the main focus of cutaneous leishmaniasis in western Turkey(Soc Vector Ecology, 2011) Ozbel, Yusuf; Balcioglu, I. Cuneyt; Olgen, M. Kirami; Simsek, Fatih M.; Toz, Seray Ozensoy; Ertabaklar, Hatice; Demir, SamiyeAn entomological survey was conducted to determine the spatial distribution of phlebotomine fauna and understand the effect of environmental factors. The entomological survey was carried out during 2006-2007 in a study area in the rural area of Aydin province, near the Kusadasi town where VL, CL, and canine leishmaniasis (CanL) are endemic. In 2006 and 2007, 132 locations were sampled using sticky traps mainly on embankments. Detailed environmental and meteorological information was also collected for each location. The results of entomological studies indicated that the probable vectors are Phlebotomus tobbi and P. neglectus for VL and CanL, and P. similis for CL in this western leishmaniasis focus. The data revealed a correlation between their presence and spatial variables such as altitude, sampling site location, and humidity. The distribution areas of probable vector species in this study area allowed the identification of risk levels, which may provide useful information to guide the leishmaniasis research in endemic regions.Öğe The Toxicity of Essential Oils From Three Origanum Species Against Head Louse, Pediculus humanus capitis(Springer Int Publ Ag, 2021) Arserim, Suha K.; Cetin, Huseyin; Yildirim, Ahmet; Limoncu, M. Emin; Cinbilgel, Ilker; Kaya, Tugba; Ozbel, YusufPurpose Pediculosis caused by human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae) is a public health problem with a high prevalence, especially among children in school age. Different chemical pediculicides (insecticides) are used against lice but the repeated application of these pediculicides for the treatment of P. humanus capitis infestation in the past decades has resulted in the development of resistance. The plant essential oils have been used as alternative sources of lice treatment agents. Pediculicidal activity of the essential oils of three Origanum species (O. onites, O. majorana and O. minutiflorum) against P. humanus capitis adults was examined in this study. Methods Essential oils from aerial parts of three Origanum species were obtained by hydrodistillation using a Clevenger-type apparatus. P. humanus capitis specimens used were obtained from infested children by combing method at primary schools. Adult lice were exposed to three dilutions (1%, 0.5% and 0.1% w/v) of tested oils for 5 min using the adult immersion test. Results According to the results, all Origanum essential oils at 1% concentration have been shown to significantly decrease the rate of limb, bowel and abdomen movements, producing more than 90% mortality after 12 h. Conclusion Our results indicated that Origanum essential oils can be used for the development of new pediculicides against head louse.
