[Self-made metal freezing plate for cryopreservation of human epididymal sperm: An experimental study].

Objective: To study the effect of a new human sperm freezing method on the sperm recovery rate and search for an optimal method for cryopreservation of human epididymal sperm.

Methods: We collected semen samples from 76 men with obstructive azoospermia by percutaneous epididymal sperm aspiration and divided each sample into two parts to be cryopreserved with a self-made metal freezing plate (the experimental group) or by slow freezing (the control group), respectively. We measured the percentage of progressively motile sperm (PMS) with the computer-assisted semen analysis system and compared the membrane function, DNA fragmentation index (DFI), acrosin activity and morphological abnormality of the sperm between the two groups before and after cryopreservation.

Calcium maintained higher quality and enhanced resistance against chilling stress by regulating enzymes in reactive oxygen and biofilm metabolism of Chinese winter jujube fruit.

The postharvest senescence of Chinese winter jujube fruit can be effectively delayed by refrigerated storage. However, chilling injury often occurs in jujube fruit during cold storage. In this study, Chinese winter jujubes were sprayed with CaCl (4%) 3 times at intervals of 2 hr on the day of refrigeration.

[Purification and identification of recombinant varicella-zoster virus glycoprotein E].

Objective: To purify and identify recombinant Varicella-Zoster Virus Glycoprotein E.

Methods: The recombinant plasmid pGEX-VZVgE was induced by isopropyl-beta-D-thiogalactoside (IPTG), the fusion protein was purified with affinity chromatography column; then the purified fusion protein was cleaved by thrombin, and the product's antigenicity was examined by Western blot.

Results: The product of pGEX-VZVgE induced by IPTG was separated from the mixture proteins by the affinity chromatography column, the expressed fusion protein's relative molecular mass was about 98 x 10(3).