Ten prepubertal and 8 mature gilts were superovulated with PMSG and hCG, and inseminated with fresh boar semen. Zygotes were surgically recovered from oviducts 54-60 h after hCG. One and 2-cell zygotes were randomly allotted to Medium PL (modified BMOC-3 supplemented with 0.1 mM-EDTA and 1.5% BSA) or Medium G (Medium PL without pyruvate or lactate). Eggs were washed twice in medium, and placed in microdrops of medium overlaid with silicon oil for culture in an humidified 5% CO2, 5% O2, 90% N2 environment, then observed daily for 6 days. Development of eggs was dependent (P less than 0.001) on the interactive effects of age of gilt (prepubertal versus mature) and medium type (PL versus G) used in culture. A greater proportion of eggs cultured in Medium G developed further than did eggs in Medium PL (P less than 0.001). Additionally, a greater proportion of eggs from mature gilts developed further than did eggs from prepubertal gilts (P less than 0.02). We suggest that these results provide evidence that zygotes resulting from superovulation regimens of prepubertal gilts do not possess the same capacity for in-vitro development as do zygotes from pubertal gilts.

Numerical chromosome aberrations in gametes typically lead to failed fertilization, spontaneous abortion or a chromosomally abnormal fetus. By means of preimplantation genetic diagnosis (PGD), we now can screen human embryos in vitro for aneuploidy before transferring the embryos to the uterus. PGD allows us to select unaffected embryos for transfer and increases the implantation rate in in vitro fertilization programs. Molecular cytogenetic analyses using multi-color fluorescence in situ hybridization (FISH) of blastomeres have become the major tool for preimplantation genetic screening of aneuploidy. However, current FISH technology can test for only a small number of chromosome abnormalities and hitherto failed to increase the pregnancy rates as expected. We are in the process of developing multi-color FISH-based technologies to score all 24 chromosomes in single cells within a three-day time limit, which we believe is vital to the clinical setting. Also, human placental cytotrophoblasts (CTBs) at the fetal-maternal interface acquire aneuploidies as they differentiate to an invasive phenotype. About 20–50% of invasive CTB cells from uncomplicated pregnancies were found to be aneuploid, suggesting that the acquisition of aneuploidy is an important component of normal placentation, perhaps limiting the proliferative and invasive potential of CTBs. Since most invasive CTBs are interphase cells and possess extreme heterogeneity, we applied multi-color FISH and repeated hybridizations to investigate the feasibility of a full karyotype analysis of individual CTBs. In summary, this study demonstrates the strength of Spectral Imaging analysis and repeated hybridizations, which provides a basis for full karyotype analysis of single interphase cells.

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Regular use of non-steroidal anti-inflammatory drugs (NSAIDs) may be protective against tumours, including breast cancer. We have studied the effects of ibuprofen and aspirin on DNA damage in lymphocytes obtained from breast cancer patients and healthy female controls. Both nanoparticle (NPs) and bulk formulations were used in the comet and micronucleus (MN) assays. Non-toxic doses (250 ng/ml ibuprofen; 500 ng/ml aspirin) were tested. Aspirin, both bulk and nano formulations, significantly reduced DNA damage measured with the comet and micronucleus assays; the nano formulation was more effective. Ibuprofen was not effective in the comet assay but showed a significant reduction in MN frequency, with the nano formulation being more effective. NPs may have better penetration through the nuclear membrane relative to the bulk formulation. NSAIDs such as aspirin and ibuprofen may have a promising role in cancer prevention and treatment.

Summary. Eggs were collected from 60 virgin ICR mice 15\ m=1/ 2\ h after synchronization of ovulation with PMSG and hCG from control females and those exposed for 15\ m=1/ 2\ h to hyperthermic conditions (35 \ m=+-\1\s=deg\C, 65 \m=+-\3% relative humidity) immediately after the hCG injection. Eggs were classified for analysis as monocellular, bicellular, tricellular equal, tricellular unequal, multicellular and degenerate. Egg class frequencies were affected by increasing atypical forms (P < 0\m=.\01). Stressed animals had significantly larger cells when an analysis of variance was performed on the bicellular classification, but there was no effect on ovum diameter.