Sperm preparation for intracytoplasmic sperm injection (ICSI) is described and the effect of high speed centrifugation during preparation on fertilization rate is evaluated. No significant differences were found in the 2-pronuclear or abnormal fertilization rates between sibling oocytes injected with sperm prepared by swim-up or mini-Percoll combined with high speed centrifugation. The high fertilization rate obtained with both methods indicates that high speed centrifugation is not necessary to prepare sperm for ICSI. Fertilization rates were also compared for sperm obtained from ejaculates, fresh and frozen epididymal aspirates, and testicular biopsies. High fertilization rates were obtained from all groups but they were significantly higher in those oocytes injected with epididymal sperm (78% per oocyte surviving injection). The high fertilization rate with epididymal sperm may reflect sperm quality or may result from the method of sperm preparation for injection. Fertilization after the injection of sperm from which the tail was dislodged during immobilization was compared with that obtained using intact sperm. A significantly lower rate of 2-pronuclear fertilization was found in those oocytes injected with sperm heads only (55%) compared with intact sperm (68%), although cleavage rates between the two groups were similar. The use of hypo-osmotic medium to select potentially live sperm from an immotile sample is also described and fertilization was obtained after the injection of sperm with a structural defect which were selected using this technique. These results indicate that high fertilization rates can be obtained with ejaculated, epididymal and testicular sperm without special treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Cadmium, a heavy metal, is a toxic environmental and industrial pollutant. Exposure to cadmium can lead to the toxic effects in a variety of tissues, also including the brain. The present study investigated the effect of cadmium exposure on the histopathology of cerebral cortex in juvenile mice. Juvenile mice were randomly divided into control, low (1.87 mg/kg), medium (3.74 mg/kg), and high (7.48 mg/kg) dose groups. After cadmium exposure by drinking water for 10 days, the cerebral cortex was obtained for histopathology studies. The medium and high dose of cadmium, rather than low dose, could induce the histopathology alterations of cerebral cortex in a dose-dependent manner. In the high-dose group, microstructure significantly showed pia mater encephali divorcing from cerebral cortex layer, serious hyperemia of blood capillary in pia mater encephali and cerebral cortex, broadening vessel peripheral clearance, a large number of eosinophil leukocyte infiltrating around blood vessel, vacuolar degeneration in part granule cells, and obviously increasing apoptotic cells. Ultrastructure obviously displayed marginalized heterochromatin, incomplete or fused nuclear membranes, broadened perinuclear space, ambiguous mitochondria cristae, decreased synaptic cleft, and fused presynaptic and postsynaptic membrane. Our results revealed that cadmium at the middle and high dose could induce obvious microstructure and ultrastructure alterations of cerebral cortex in juvenile mice, which may be one important mechanism of cadmium neurotoxicity.

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ABSTRACT. Numerous studies have evaluated the association be tween Arg399Gln polymorphism of DNA repair gene XRCC1 and cervical carcinoma risk. However, the spe cific association is still controversial. To assess the relationship between XRCC1 Arg399Gln polymorphism and cervical carcinoma, we conducted a comprehensive meta-analysis of 10 case-control studies with 2051 cervical carcinoma cases and 2919 controls. Meta-analysis results based on all the studies showed a significant association between XRCC1 Arg399Gln polymorphism and cervical carcinoma risk (GlnGln vs ArgArg: OR = 1.29, 95%CI = 0.90-1.85; GlnGln vs ArgGln: OR = 1.15, 95%CI = 0.93-1.43; the dominant model: OR = 0.80, 95%CI = 0.66-0.99; the recessive model: OR = 1.18, 95%CI = 0.93-1.49). In the subgroup analysis by ethnicity, the results also showed significant association between XRCC1 Arg399Gln polymorphism and susceptibility to cervical carcinoma in both Caucasian and Asian populations. The Arg399Gln polymorphism in the XRCC1 gene may be related to the increased risk of cervical carcinoma. Conclusive evidence on the effects of the variants in cervical carcinoma should be addressed in further studies.

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