This study examined the effects of tamoxifen at different concentrations and treatment periods on proliferation of a human cervical cancer cell line, HeLa. As in the previous studies, Estrogen did not have an effect on the cellular proliferation at low concentrations but significantly reduced proliferation at high concentration (5 ug/ml) based on MTT assay. Treatment with tamoxifen had similar effects. It did not have any significant effect on the HeLa cell proliferation at low concentrations, but significantly reduced proliferation at high concentration (10 uM). In addition, combined treatment with both estrogen and tamoxifen did not alter the inhibitory effects of either estrogen or tamoxifen on cellular proliferation. The inhibitory effects by tamoxifen on HeLa cell proliferation did not differ among different treatment periods. This suggests that tamoxifen may exert anti- proliferative effects at high concentration but does not have synergistic or antagonistic effects against estrogen on HeLa cell proliferation.

To avoid hyperacute rejection of xenografts, α1,3-galactosyltransferase knock-out (GalT KO) pigs have been produced. In this study, we examined whether Sia-containing glycoconjugates are important as an immunogenic non-Gal epitope in the pig liver with disruption of α1,3-galactosyltransferase gene. The target cells were then used as donor cells for somatic cell nuclear transfer (scNT). A total of 1,800 scNT embryos were transferred to 10 recipients. One recipient developed to term and naturally delivered two piglets. Real-time RT-PCR and glycosyltransferase activity showed that α2,3-sialyltransferase (α2,3ST) and α2,6-sialyltransferase (α2,6ST) in the heterozygote GalT KO liver have higher expression levels and activities compared to controls, respectively. According to lectin blotting, sialic acidcontaining glycoconjugate epitopes were also increased due to the decreasing of α-Gal in heterozygote GalT KO liver, whereas GalNAc-containing glycoconjugate epitopes were decreased in heterozygote GalT KO liver compare to the control. Furthermore, the heterozygote GalT KO liver showed a higher Neu5Gc content than control. Taken together, these finding suggested that the deficiency of GalT gene in pigs resulted in increased production of Neu5Gc-bounded epitopes (H-D antigen) due to increase of α2,6-sialyltransferase. Thus, this finding suggested that the deletion of CMAH gene to the GalT KO background is expected to further prolong xenograft survival.

Cellular uptake of nanoparticles for stem cell labeling and tracking is a critical technique for biomedical therapeutic applications. However, current techniques suffer from low intracellular labeling efficiency and cytotoxic effects, which has led to great interest in the development of a new labeling strategy. Using silica-coated nanoparticles conjugated with rhodamine B isothiocyanate (RITC) (SR), we tested the cellular uptake efficiency, biocompatibility, proliferation or differentiation ability with murine bone marrow derived hematopoietic stem/progenitor cells. The bone marrow hematopoietic cells showed efficient uptake with SR with dose or time dependent manner and also provided a higher uptake on hematopoietic stem/progenitor cells. Biocompatibility tests revealed that the SR had no deleterious effects on cell cytotoxicity, proliferation, or multi-differentiation capacities in vitro and in vivo. SR nanoparticles are advantageous over traditional labeling techniques as they possess a high level of cellular internalization without limiting the biofunctionality of the cells. Therefore, SR provides a useful alternative for gene or drug delivery into hematopoietic stem/progenitor cells for basic research and clinical applications.

AMI로 SES 혹은 PES 시술을 시행받은 모든 환자에서 4년 이상의 임상추적 기간이 지난 환자를 대상으로 데이터 를 분석하여 두 스텐트의 안전성과 유용성을 비교해 보고자 하였다. 2004년 1월 1일부터 2006년 8월 31일까지 본원 에서 ST분절 상승 혹은 ST 분절 비상승 급성심근경색증 (STEMI or NSTEMI)로 진단되어 입원 기간 중 관동맥중재 술을 시행받은 환자 중 SES 혹은 PES 삽입술이 시행된 환자를 대상으로 후향적 분석을 시행하였다. 그리고 사망, 심 장사. 심근경색증, 표적 혈관재관류술, 스텐트 혈전증 발생에 대해 분석하였다. 연구 기간 동안 총 668명의 급성심근경색증 환자가 중 522명만 연구 대상에 포함 사망 (18.3±3.0% vs. 14.6±2.2%, p=0.26), 심장사(11.2±2.6% vs. 6.8±1.52%, p=0.39), 심근경색증 (6.4±1.8% vs. 3.3±1.1%, p=0.31), and 스텐트 혈전증 (5.4±1.7% vs. 3.2±1.1%, p=0.53) 표적 혈관재관류술(TVR) (10.0±3.0% vs. 4.0±1.2%, p=0.008) and 심혈관계 임상사건(MACE) (29.4±3.5% vs. 19.4±2.5%, p=0.003) 급성심근경색증의 초기 치료에 약물방출스텐트인 SES와 PES의 4년 장기 임상 성적을 조사한 본 연구를 통해 전체 환자를 대상으로 분석하였을 때 두 스텐트의 장기 사망률, 심장사. 심근경색증, 표적 혈관재관류술, 스텐트 혈전증의 발생은 차이가 없었으나 TVR 및 MACE의 발생은 PES 삽입 환자가 SES삽입 환자보다 유의하게 높았다.