Differential impact of four sperm preparation techniques on sperm motility, morphology, DNA fragmentation, acrosome status, oxidative stress, and mitochondrial activity: A prospective study.

BACKGROUND: Suboptimal human semen handling in vitro may induce sperm damage. However, the effects of semen swim-up, pellet swim-up, density gradient, and density gradient followed by SU on sperm motility, morphology, DNA fragmentation, acrosome reaction, intracellular reactive oxygen species, and mitochondrial activity were not fully understood. OBJECTIVES: To study the impact of four sperm preparation techniques on sperm functional parameters. MATERIALS AND METHODS: This study was conducted on 60 infertile men with a minimum sperm concentration of 20 × 106 /ml and total sperm motility of ≥30%. Each raw semen sample was divided into four aliquots. Each aliquot was prepared by one of the tested techniques. Various sperm characteristics were assessed before and after sperm preparation. RESULTS: Density gradient and density gradient followed by SU resulted in significantly higher DNA fragmentation percentages compared with semen swim-up (p < 0.001 and p < 0.001, respectively) and pellet swim-up (p < 0.001 and p < 0.001, respectively). Significantly higher percentages of spermatozoa with intact acrosome were detected in semen swim-up (p < 0.001) and pellet swim-up (p < 0.001) compared with raw semen. The percentage of reactive oxygen species-positive spermatozoa was significantly higher after pellet swim-up (p < 0.001), density gradient (p < 0.001), and density gradient followed by SU (p < 0.001) than raw semen. In addition, the percentages of 100% stained midpiece (active mitochondria) were significantly higher in semen swim-up (p < 0.001) and pellet swim-up (p < 0.001) compared with raw semen. DISCUSSION AND CONCLUSION: To the best of our knowledge, this is the first report comparing the impact of these techniques on various sperm functional parameters. Semen swim-up was more effective than density gradient in selecting better spermatozoa in terms of DNA integrity, reactive oxygen species levels, acrosome status, and mitochondrial activity. Randomized clinical trials comparing these four techniques are required to test their impact on embryo development and pregnancy outcomes.

Contribution to the knowledge of the clown beetle fauna of Lebanon, with a key to all species (Coleoptera, Histeridae).

The occurrence of histerids in Lebanon has received little specific attention. Hence, an aim to enrich the knowledge of this coleopteran family through a survey across different Lebanese regions in this work. Seventeen species belonging to the genera Atholus Thomson, 1859, Hemisaprinus Kryzhanovskij, 1976, Hister Linnaeus, 1758, Hypocacculus Bickhardt, 1914, Margarinotus Marseul, 1853, Saprinus Erichson, 1834, Tribalus Erichson, 1834, and Xenonychus Wollaston, 1864 were recorded. Specimens were sampled mainly with pitfall traps baited with ephemeral materials like pig dung, decayed fish, and pig carcasses. Several species were collected by sifting soil detritus, sand cascading, and other specialized techniques. Six newly recorded species for the Lebanese fauna are the necrophilous Hister sepulchralis Erichson, 1834, Hemisaprinus subvirescens (Ménétriés, 1832), Saprinus (Saprinus) externus (Fischer von Waldheim, 1823), Saprinus (Saprinus) figuratus Marseul, 1855, and Saprinus (Saprinus) niger (Motschulsky, 1849) all associated with rotting fish and dung, and the psammophilous Xenonychus tridens (Jacquelin du Val, 1853). With the exception of Hister sepulchralis, all these taxa belong to the Saprininae subfamily. A most likely undescribed species of Tribalus (Tribalus) (Tribalinae) has also been collected in detritus at wet places near rivers in Lebanon. Because of the complexity of the genus Tribalus, with possible numerous new species present in the circum-Mediterranean area, the Lebanese species is not described herein, pending a revision of the genus. This study advocates further research aimed at improving taxonomic and ecological knowledge of this coleopteran family in Lebanon. The number of Histeridae species currently known from Lebanon stands at 41; a key to all species including images is included.

Forensically Relevant Blow Flies in Lebanon Survey and Identification Using Molecular Markers (Diptera: Calliphoridae).

Calliphoridae are among the first insects associated to decomposing animal remains. We have collected 1,841 specimens of three calliphorid genera: Calliphora, Lucilia, and Chrysomya, from different Lebanese localities as a first step in implementing a database of insects of forensic relevance for the country. Blow-flies are crucial for the estimation of the postmortem interval. DNA-based identification is a rapid and accurate method, often used for morphologically similar species, especially for immatures or incomplete specimens. In this study, we test the suitability of three genetic markers to identify adults and immature stages of calliphorids, viz., mitochondrial cytochrome c oxidase subunit I (COI) barcode, a region including partial sequences of mitochondrial Cyt-b-tRNAser-ND1, and second internal transcribed spacer (ITS2) region of nuclear ribosomal DNA. Forty Lebanese specimens of various developmental stages (egg, larva, wandering third instar, pupa, newly emerged adult, and mature adult) were identified among the three calliphorid genera: Calliphora, Lucilia, and Chrysomya, and compared with published sequences to confirm their specific assignation. Phylogenetic analyses showed the robustness of ITS2 and COI to identify calliphorids at species level. Nevertheless, ITS2 failed to discriminate Lucilia caesar (Linnaeus) (Diptera, Calliphoridae) from Lucilia illustris (Meigen) (Diptera, Calliphoridae), and COI had a similar issue with Lucilia sericata (Meigen) (Diptera, Calliphoridae) and Lucilia cuprina (Wiedemann) (Diptera, Calliphoridae). Thus, these two markers are complementary. This work contributes new nucleotide sequences for Lebanon. It is a first step in implementing a molecular database of forensic relevant insects for the country.

Contribution to the knowledge of Saprinus Erichson, 1834 of forensic relevance from Lebanon (Coleoptera, Histeridae).

Many histerid beetles are necrophilous on carrion during both active and advanced stages of decomposition. In this study, 13 species of Saprinus were recorded on carrion from Lebanon, containing eight that are new for the Lebanese fauna. The following Saprinus species are newly recorded from Lebanon: 1) Saprinus (S.) caerulescens caerulescens (Hoffmann, 1803); 2) S. (S.) calatravensis Fuente, 1899; 3) S. (S.) chalcites (Illiger, 1807); 4) S. (S.) godet (Brullé, 1832); 5) S. (S.) maculatus (P. Rossi, 1792); 6) S. (S.) strigil Marseul, 1855; 7) S. (S.) submarginatus J. Sahlberg, 1913; and 8) S. (S.) tenuistrius sparsutus Solsky, 1876. The peak activity was recorded, key for the species is provided, and habitus images and male genitalia are illustrated in order to facilitate their taxonomic identifications. Saprinus species are diverse and common on animal carcass; they were likewise collected from a human cadaver in Lebanon. Preliminary comments on biology and distribution of the studied species are given. Our paper represents the first faunistic study on Histeridae from Lebanon. A rigorous research program regarding the biology of Saprinus in Lebanon and the neighbouring countries would greatly improve the knowledge of the diversity, activity, and possible forensic value of Saprinus.