Protective effect of vitamin C and lycopene on the in vitro fertilization capacity of sex-sorted bull sperm by inhibiting the oxidative stress.

The fertilization capacity of sex-sorted sperms is seriously decreased, which inhibits its wide application. However, little information is still available about the effect of vitamin C (VC) and lycopene (Lyc) on the fertilization capacity of sex-sorted bull sperm. In this study, the washing medium and fertilization medium of sex-sorted sperm from three bull individuals were supplemented with different concentrations of VC (0, 1 × 10-3 , 1 × 10-4 , 1 × 10-5 , 1 × 10-6  M) or Lyc (0, 1 × 10-4 , 1 × 10-5 , 1 × 10-6 , 1 × 10-7 ). After washing twice and incubation for 1.5 hr, the malondialdehyde (MDA) level, phosphatidylserine (PS) translocation, membrane potential (Δψm) and IVF (in vitro fertilization) ability of sex-sorted sperm were investigated. For the sex-sorted sperm of bulls A, B and C, 1 × 10-3  M VC or 1 × 10-4  M Lyc treatment significantly decreased their MDA levels and PS translocation and increased their Δψm levels and cleavage rates after IVF. When blastocysts were concerned, 1 × 10-4  M Lyc significantly improved the blastocyst rates and their IFN-tau expression of bulls A and C. In conclusion, supplementation of 1 × 10-3  M VC or 1 × 10-4  M Lyc in washing and fertilization medium contributed greatly to improving the fertilization capacity of sex-sorted bull sperm during IVF procedure.

Paleoclimatic information recorded in fluid inclusions in halites from Lop Nur, Western China.

The homogenization temperature (Th) of primary fluid inclusions in halite can be used for paleoclimate interpretations. Lop Nur, in Central Asia, is an extremely arid zone where large amounts of glauberite were deposited from the late Middle to Late Pleistocene. This deposition was accompanied by formation of large-scale potash-bearing brines. However, quantitative paleotemperature data are still lacking, hindering reconstruction of Quaternary climate conditions and their control over potash formation. We measured the Th of inclusions in halite from the salt field and the top of Upper Pleistocene strata in Lop Nur. The maximum homogenization temperature (Th MAX) of inclusions in halite from the salt field was 41.1 °C, consistent with the maximum ambient temperature (43.4 °C) in the same period. The Th MAX of inclusions in halite from the Upper Pleistocene strata ranged from 35.6 °C to 43 °C, where maximum air temperatures may have reached 37.9 °C to 45.3 °C. The results show that a hot and arid climate prevailed in Lop Nur at the end of the Late Pleistocene. Furthermore, changes of the brine chemical composition due to supply variations instead of climate change, may have caused glauberite deposition to cease at the end of the Late Pleistocene.