Presence of Extensive Wolbachia Symbiont Insertions Discovered in the Genome of Its Host Glossina morsitans morsitans

Tsetse flies (Glossina spp.) are the cyclical vectors of Trypanosoma spp., which are unicellular parasites responsible for multiple diseases, including nagana in livestock and sleeping sickness in humans in Africa. Glossina species, including Glossina morsitans morsitans (Gmm), for which the Whole Genome Sequence (WGS) is now available, have established symbiotic associations with three endosymbionts: Wigglesworthia glossinidia, Sodalis glossinidius and Wolbachia pipientis (Wolbachia). The presence of Wolbachia in both natural and laboratory populations of Glossina species, including the presence of horizontal gene transfer (HGT) events in a laboratory colony of Gmm, has already been shown. We herein report on the draft genome sequence of the cytoplasmic Wolbachia endosymbiont (cytWol) associated with Gmm. By in silico and molecular and cytogenetic analysis, we discovered and validated the presence of multiple insertions of Wolbachia (chrWol) in the host Gmm genome. We identified at least two large insertions of chrWol, 527,507 and 484,123 bp in size, from Gmm WGS data. Southern hybridizations confirmed the presence of Wolbachia insertions in Gmm genome, and FISH revealed multiple insertions located on the two sex chromosomes (X and Y), as well as on the supernumerary B-chromosomes. We compare the chrWol insertions to the cytWol draft genome in an attempt to clarify the evolutionary history of the HGT events. We discuss our findings in light of the evolution of Wolbachia infections in the tsetse fly and their potential impacts on the control of tsetse populations and trypanosomiasis.     

Development and validation of a new gas flame ionization detector method for the determination of finasteride in tablets

A simple, rapid, and sensitive method based on gas chromatography with flame ionization detection is described for the determination of finasteride in tablets. The method is based on the derivatization of finasteride with N,O-bis(trimethylsilyl)trifluoroacetamide-1% trimethylchlorosilane at 60 degrees C for 30 min. The method was validated for specificity, linearity, precision, accuracy, robustness, and limit of quantification. The degree of linearity of the calibration curves, the percentage recoveries of finasteride, and the limit of detection (LOD) and limit of quantification (LOQ) for the gas chromatographic method were determined. The assay was linear over the concentration range of 10 to 50 microg ml(-1) (R approximately 0.999). LOQ and LOD (signal/noise ratio = 10) were found to be 10 and 2 microg ml(-1), respectively. The method was found to be simple, specific, precise, accurate, and reproducible. All of the validation parameters were within the acceptance range. The developed method was applied successfully to estimate the amount of finasteride in tablets. The results were compared statistically with those obtained by the official method using t and F tests. There was no significant difference between the two methods with respect to mean values and standard deviations at the 95% confidence level.     

Total sialic acid profile in regressing and remodelling organs during the metamorphosis of marsh frog (Pelophylax ridibundus Pallas 1771)

This study aimed to investigate the functional relationship of sialic acid in regressing and remodelling organs such as the tail, small intestine and liver during the metamorphosis of Pelophylax ridibundus. For this purpose, four groups were composed according to developmental periods by considering Gosner's criteria (1964). Our findings showed that the sialic acid content of the larval tail has an opposite profile to cell death process. Although the sialic acid content of the small intestine and liver did not change evidently during metamorphosis, it increased after the completion of metamorphosis. Frog tail extensively exhibited cell death process and decreased proliferative activity and underwent complete degeneration during metamorphic climax. In spite of increased apoptotic index, a decreased sialic acid level in the tail tissues during climax can be the indication of a death cell removal process. However, the intestine and the liver included both cell death and proliferative process and remodelling in their adult forms. Thus, their sialic acid profiles during metamorphosis were different from the tail's profile. These data show that sialic acid may be an indicator of the presence of some cellular events during metamorphosis and that it can have different roles in the developmental process depending on the organ's fate throughout metamorphosis. Copyright © 2012 John Wiley & Sons, Ltd.     

Genome-Wide Comparative Analysis of Chemosensory Gene Families in Five Tsetse Fly Species

For decades, odour-baited traps have been used for control of tsetse flies (Diptera; Glossinidae), vectors of African trypanosomes. However, differential responses to known attractants have been reported in different Glossina species, hindering establishment of a universal vector control tool. Availability of full genome sequences of five Glossina species offers an opportunity to compare their chemosensory repertoire and enhance our understanding of their biology in relation to chemosensation. Here, we identified and annotated the major chemosensory gene families in Glossina. We identified a total of 118, 115, 124, and 123 chemosensory genes in Glossina austeni, G. brevipalpis, G. f. fuscipes, G. pallidipes, respectively, relative to 127 reported in G. m. morsitans. Our results show that tsetse fly genomes have fewer chemosensory genes when compared to other dipterans such as Musca domestica (n>393), Drosophila melanogaster (n = 246) and Anopheles gambiae (n>247). We also found that Glossina chemosensory genes are dispersed across distantly located scaffolds in their respective genomes, in contrast to other insects like D. melanogaster whose genes occur in clusters. Further, Glossina appears to be devoid of sugar receptors and to have expanded CO₂ associated receptors, potentially reflecting Glossina''s obligate hematophagy and the need to detect hosts that may be out of sight. We also identified, in all species, homologs of Ir84a; a Drosophila-specific ionotropic receptor that promotes male courtship suggesting that this is a conserved trait in tsetse flies. Notably, our selection analysis revealed that a total of four gene loci (Gr21a, GluRIIA, Gr28b, and Obp83a) were under positive selection, which confers fitness advantage to species. These findings provide a platform for studies to further define the language of communication of tsetse with their environment, and influence development of novel approaches for control.     

Hybrid solar cells

Historically, conventional solar cells were built from inorganic materials such as silicon. Although the efficiency of such conventional solar cells is high, very expensive materials and energy intensive processing techniques are required.Hybrid and photoelectrochemical (dye sensitized) solar cells have been the cheap alternatives for conventional silicon solar cells. A hybrid solar cell consists of a combination of both organic and inorganic materials therefore, combines the unique properties of inorganic semiconductors with the film forming properties of the conjugated polymers. Organic materials are inexpensive, easily processable and their functionality can be tailored by molecular design and chemical synthesis. On the other hand, inorganic semiconductors can be manufactured as nanoparticles and inorganic semiconductor nanoparticles offer the advantage of having high absorption coefficients and size tunability. By varying the size of the nanoparticles the bandgap can be tuned therefore the absorption range can be tailored.In this short review, we will focus on the concepts of organic/inorganic “hybrid” solar cells.     

Aflatoxin M<Subscript>1</Subscript> in human breast milk in southeastern Turkey

This study was performed to determine aflatoxin M₁ (AFM₁) in human breast milk samples collected in ?anl?urfa, located in Southeastern region of Turkey, and to investigate a possible correlation between AFM₁ occurrence (frequency and levels) and sampling seasons. Human breast milk samples collected in December 2014 and in June 2015 from a total of 74 nursing women, both outpatient and inpatient volunteers in hospitals located in ?anl?urfa, Turkey, were analyzed using competitive enzyme-linked immunosorbent assay (ELISA) for the presence of AFM₁. AFM₁ was detected in 66 (89.2%) out of 74 samples at an average concentration of 19.0 ± 13.0 ng/l (min.-max., 9.6–80 ng/l). There was a statistically significant difference between December and June concerning AFM₁ levels (p < 0.05). Further detailed studies will be needed to determine the main sources of aflatoxins in food, to establish protection strategies against maternal and infant exposure to these mycotoxins.     

A case of myiasis in a patient with psoriasis from Turkey

Myiasis infestations caused by the larvae of flies mostly belonging to Cyclorapha suborders are frequently encountered in Turkey, which is located in the subtropical zone. The skin is a common site for myiasis, and the infestations are likely to develop in infected tissues and poorly attended wounds of the skin.

The case, a 30-year-old male patient, was diagnosed with psoriasis 18 years ago. He had psoriatic scales on his right big toe and was receiving corticosteroid and immunosuppressive drugs.

A total of 11 fly larvae were removed from the infected right first toe of the patient. Structures of the stigmas seen in the cross-sections taken from the final segments of these larvae were examined and determined as Sarcophaga spp. larvae.

Patients with infected tissues should be extremely cautious about their wound hygiene and take required fly control measures especially during summer as flies can find a suitable environment for sustenance.