Browsing by Author "Omondi Z.N."

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Toxicity of Thiamethoxam on Field-Collected Sand Flies (Diptera: Psychodidae) from Different Regions of Turkey
    (Oxford University Press, 2020) Arserim S.K.; Çetin H.; Yetişmiş K.; Omondi Z.N.; Özbel Y.; Johnson R.
    Phlebotomine sand flies (Diptera: Psychodidae) are the vectors of human and canine leishmaniasis, sand fly fever, and other arboviruses and bacteria. The control of sand flies is recommended by World Health Organization throughout the world. In this study, we investigated the susceptibility of field-collected sand flies against thiamethoxam in Turkey. The adult sand flies collected were from five different locations in three provinces; Yeşilöz and Büyükplnar districts in Antalya province, Develi district in Kayseri province, and Üçplnar and Baylndlrllk districts in Manisa province. They were investigated using two different doses (0.125 and 0.25 g ai/m2) of thiamethoxam under laboratory conditions. After 1-h exposure, all sand flies were found highly susceptible to thiamethoxam and both test doses caused 100% mortality after 24 h. Considering the KDT50 time, flies collected from Yeşilöz district in Antalya province were found to be most sensitive and flies collected from Üçplnar district in Manisa province were found as the most resistance to thiamethoxam. The results show that Turkish sand flies were highly susceptible to thiamethoxam and it can be used for the control of sand flies in the field. © 2019 Published by Oxford University Press on behalf of Entomological Society of America 2019.
  • No Thumbnail Available
    Item
    Entomological Survey of the Sand Fly Fauna of Kayseri Province: Focus on Visceral and Cutaneous Leishmaniasis in Central Anatolia, Turkey; [Kayseri İlinin Kum Sineği Faunası Üzerine Entomolojik Çalışma: Türkiye’nin Orta Anadolu Bölgesi’nde Yeni Bir Kutanöz Leishmaniasis Odağı]
    (Galenos Publishing House, 2020) Omondi Z.N.; Demir S.; Arserim S.K.
    Objective: In Turkey, leishmaniasis occurs in two clinical forms: cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). CL has been reported mainly from south-eastern Anatolia and the eastern part of the Mediterranean region, whereas VL is sporadic in almost all geographical regions of Turkey. Both clinical forms of the disease have been recorded in Kayseri province for decades, but no study has been conducted on the sand fly fauna in this area. Therefore, we determine the species composition and population dynamics of sand flies prevalent in Kayseri province and identify possible vector species. Methods: Data related to the recent locations of CL and VL cases were obtained from the Ministry of Health, and sand flies were collected in 14 localities of different districts using CDC light traps. The specimens were transferred to the laboratory in 70% ethanol, and morphological identification to the species level was performed using previously written keys. Results: A total of 1,636 sand fly specimens were collected. Morphological identification revealed eight species of the genus Phlebotomus (P. perfiliewi s.l., P. halepensis, P. simici, P. major s.l., P. papatasi, P. tobbi, P. sergenti and P. mascittii) and one species of the genus Sergentomyia (S. dentata). Among all specimens, members of subgenus Adlerius (54.58%) formed the dominant group, followed by the subgenus Larroussius (43.76%). Conclusion: Our results showed that P. halepensis, belonging to subgenus Adlerius, and P. perfiliewi, belonging to the subgenus, are probable vectors of cutaneous and VL in the province, respectively. © 2020 Turkish Society for Parasitology.
  • No Thumbnail Available
    Item
    Host–Parasite Interactions: Regulation of Leishmania Infection in Sand Fly
    (Springer Science and Business Media Deutschland GmbH, 2022) Omondi Z.N.; Arserim S.K.; Töz S.; Özbel Y.
    Purpose: Sand flies are the only proven vectors of leishmaniases, a tropical neglected disease endemic in at least 92 countries. Vector–parasite interactions play a significant role in vector-borne disease transmission. There are various bottlenecks to Leishmania colonization of the sand fly midgut. Such bottlenecks include the production of innate immune-related molecules, digestive proteases, parasite impermeable peritrophic membrane, and resident gut microbiota. These barriers determine the parasite load transmitted and, consequently, the disease outcome in mammalian host. Therefore, it is important to understand the molecular responses of both sand fly and Leishmania during infection. Method: Here, we reviewed the published literature on sand fly–Leishmania interactions bringing together earlier and current findings to highlight new developments and research gaps in the field. Conclusion: Recent research studies on sand fly–Leishmania interaction have revealed contrasting observations to past studies. However, how Leishmania parasites evade the sand fly immune response still needs further research. Sand fly response to Leishmania infection can be best understood by analyzing its tissue transcriptome. Better characterization of the role of midgut components could be a game changer in development of transmission-blocking strategies for leishmaniasis. © 2022, The Author(s) under exclusive licence to Witold Stefański Institute of Parasitology, Polish Academy of Sciences.
  • No Thumbnail Available
    Item
    Trypanosomes and gut microbiota interactions in triatomine bugs and tsetse flies: A vectorial perspective
    (John Wiley and Sons Inc, 2024) Omondi Z.N.; Caner A.; Arserim S.K.
    Triatomines (kissing bugs) and tsetse flies (genus: Glossina) are natural vectors of Trypanosoma cruzi and Trypanosoma brucei, respectively. T. cruzi is the causative agent of Chagas disease, endemic in Latin America, while T. brucei causes African sleeping sickness disease in sub-Saharan Africa. Both triatomines and tsetse flies are host to a diverse community of gut microbiota that co-exist with the parasites in the gut. Evidence has shown that the gut microbiota of both vectors plays a key role in parasite development and transmission. However, knowledge on the mechanism involved in parasite–microbiota interaction remains limited and scanty. Here, we attempt to analyse Trypanosoma spp. and gut microbiota interactions in tsetse flies and triatomines, with a focus on understanding the possible mechanisms involved by reviewing published articles on the subject. We report that interactions between Trypanosoma spp. and gut microbiota can be both direct and indirect. In direct interactions, the gut microbiota directly affects the parasite via the formation of biofilms and the production of anti-parasitic molecules, while on the other hand, Trypanosoma spp. produces antimicrobial proteins to regulate gut microbiota of the vector. In indirect interactions, the parasite and gut bacteria affect each other through host vector-activated processes such as immunity and metabolism. Although we are beginning to understand how gut microbiota interacts with the Trypanosoma parasites, there is still a need for further studies on functional role of gut microbiota in parasite development to maximize the use of symbiotic bacteria in vector and parasite control. © 2024 The Authors. Medical and Veterinary Entomology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.
  • No Thumbnail Available
    Item
    Circular RNAs as a new perspective in the diagnosis and mechanism of Leishmania infections
    (Elsevier B.V., 2025) Alizadeh H.; Muftuoğlu C.; Omondi Z.N.; Mert U.; Asadi M.; Ozbilgin A.; Caner A.
    Leishmaniasis is a neglected infectious disease that affects millions of people worldwide. Visceral leishmaniasis (VL) caused by Leishmania infantum and cutaneous leishmaniasis (CL) caused by L. major/ L. tropica are the main clinical forms of this disease, which are life-threatening if not diagnosed and treated properly. Considering the problems in sampling and laboratory diagnosis of leishmaniasis, new molecular markers such as circular RNAs (circRNAs) are needed. circRNAs, a novel class of RNAs, have been one of the most promising targets for the diagnosis and prognosis of diseases. Although the therapeutic and diagnostic role of circRNAs in many diseases and some parasitic diseases are known, not much research has been done in the field of leishmaniasis. We determined the gene expressions of circRNAs in human leukemia monocytic (THP-1) cells after infection with Leishmania. For this, the human cell line THP-1 was differentiated into macrophages by Phorbol 12-myristate 13-acetate (PMA) treatment. Differentiated THP-1 cells were infected with L. infantum and L. tropica promastigotes. After 24 hours, expression levels of circRNAs were determined by RT-qPCR technique. Also, the microRNAs associated with differentially expressed circRNAs were investigated. Then, the molecular pathways associated with expressed circRNAs were obtained by GO and Reactome. The results showed that five circRNAs were differentially expressed in THP1 macrophages infected with L. infantum and L. tropica. These findings suggest that some circRNAs may be potential biomarkers for diagnosis in Leishmania-infected patients. The enrichment analysis revealed that differentially expressed circRNAs are mainly involved in the regulation of protein stability, RNA catabolic process, and P53/PTK6 signaling mechanism. This is the first study to report an overview of Leishmania-induced circRNAs, which can be potential biomarker candidate for diagnosis especially at species level. Notably, expression of some circRNAs in supernatant of Leishmania infected macrophages suggests that these genes are available in body fluids, therefore, can easily be accessed from the patient without invasive methods especially during treatment monitoring. © 2024 Elsevier B.V.