To elucidate the roles of cytokines for ex vivo expansion and orderly differentiation of hematopoietic progenitor cells, and the capacity of hematopoietic reconstitution of the expanded cells.

ENU mutagenesis is becoming one of the most powerful approaches for large-scale study of gene function. The mechanism of ENU mutagenesis, factors that affect mutation rates, the strategies of the ENU mutagenesis, screening for the phenotypes, related researches and recent progresses were introduced.

To observe the effect of polyaspartic acid (PAA) on gentamicin-induced disturbance of phospholipid metabolism in cochlea of Guinea pig.

17 kinds of conditioned media were selected by plating tests, propagation and other tests with two cell lines, C-19-2 and MESPU-13. The results suggested that the rat heart cells conditioned media (RH-CM) can inhibit the spontaneous differentiation effectively, maintain the normal diploid karyotypes and promote adherence and proliferation of mouse ES cells. The ES cells were propagated in RH-CM to the 20th passage remaining their pluripotent in vivo and in vitro differentiation ability. RH-CM can be used as supplement of ES cell media. ES cells which are cultured in media containing 70% RH-CM and on PMEF feeder can maintain their undifferentiation state and diploid karyotype. RT-PCR detection suggested that there was mLIF expression in rat heart cells.

To study the method of using BRL conditioned medium in ES cells culture.

To investigate whether the suppression of CFU-GM is caused directly by human cytomegalovirus(HCMV).

To explore whether human umbilical cord blood hematopoietic progenitor cells transduced with mutant dihydrofolate reductase(mDHFR) gene increase resistance to metrotrexate(MTX).

To investigate the possible pathogenesis of acquired pure amegakaryocytic thrombocytopenic purpura(APATP).

To observe the abnormal clonal hematopoiesis status in patients with paroxysmal nocturnal hemoglobinuria(PNH) attained complete clinical remission(CCR).

To investigate the regulatory effect of transforming growth factor-beta 1 (TGF-beta 1) on the generation of dendritic cells (DCs) from hematopoietic progenitor cells (HPCs) and its cellular and molecular mechanisms.

To examine the in vivo properties of retroviral recombinants carrying partially deleted human beta-globin gene (delta beta) and truncated erythroid enhancer (292 bp and 341 bp of 5'HS2) at the mRNA levels following short- and long-term reconstitution in mice with infected marrow cells.

To observe resistance to radiochemical agents in the mice reconstructed hematopoiesis with hematopoietic stem cells transfected by bcl-2 gene.

Comparative studies were carried out on the morphology and histology of 5 Clematis species, namely, C. intricata, C. aethusifolia, C. glauca, C. tangutica and C. hexapetala, allegedly used as "Tougucao". New characteristics, a sclerenchymatous ring composed of primary phloem fibers and lignified parenchyma cells, and a parenchymatous tertiary ring were discovered. A parameter representing the ratio of the diameter of cambium ring to the diameter of the stem (RCR) is created. A key for identification of the stems of the above five species is made according to the presence or absence of the sclerenchymatous ring, the diameter and numbers of hair cells, the thickness of fiber wall and the value of RCR, etc.

Despite the wide application of ES cell technology, little is known about the pluripotent nature of ES cells. This is partly due to the heterogeneity of ES cell population in culture. This report described the specific labelling of undifferentiated cells in ES cell lines. oct-4 gene is specifically expressed in all the totipotent cells in mouse embryos and undifferentiated ES cells. A constructed pG18NG was obtained by inserting the reporter gene beta geo into the oct-4 transcription elements. ES cell lines MESPU22 and MESPU13 were transfected with this construct and stable integrated cell clones were selected out. With the experiments of in vitro cultivation, differentiation and chimeras production, it was confirmed that we have successfully labelled the undifferentiated cells in ES cell lines, and this label was both valid in vitro and in vivo.

To investigate whether removing the compartments of hemopoietic stem cells by immunoadsorption would improve the proliferation of fetal hepatocytes after transplantation.

Mouse nestin, an intermediate filament gene, is transiently expressed during the development of the central nervous system. In order to find the clue of its function during neural development, we tried to find out the gene expression pattern during the neuronal differentiation of P19 EC cells induced RA. RT-PCR showed that nestin was transiently expressed during P19 neuron differentiation, with a peak at day 4 of this process. However, BMP4, a neural precursor cell marker, was transiently expressed with its highest level at day 6, while NF160 kD a terminal differentiated neuronal marker, was increasingly expressed during the whole process. These results implied that nestin might play some roles during the process of neural progenitor cells differentiating into neural precursor cells. Moreover, immunostaining showed that nestin was located in the neurite and the growth cone of the P19 neuron, suggesting that nestin might be also involved in the process of the establishment of neural connection.

In this study, we obtained the serum-free conditioned medium from subcultures of murine bone-marrow-derived endothelial cell line which has been established recently by ourselves. And then, molecular weight (MW) > 10 kD, 3-10 kD, 1-3 kD, 0.5-1 kD and < 0.05 kD components were sifted out from the conditioned medium (mBMEC-CM) by means of serial ultrafiltration. Assays of granulocyte-macrophage colony-forming cell (CFU-GM) were performed to examine the effects of mBMEC-CM and its ultrafiltration-prepared components. It was not observed that mBMEC-CM and MW 3-10 kD component had any significant influence on the growth of CFU-GM. However, MW > 10 kD and 0.5-1 kD components enhanced the proliferation of CFU-GM, whereas MW 1-3 kD and < 0.5 kD ones inhibited it. All these four components exerted their effects on the growth of CFU-GM in dose-dependent way. Our observations suggest that under the conditions of in vitro, murine bone marrow endothelial cells produce several active components which have promoting or inhibitory effects on the growth of CFU-GM.

To study the effects of platelet factor 4(PF4) and tetrapeptide N-acetyl-Ser-Asp-Lys-Pro(AcSDKP) on hemopoietic progenitors in mice treated with 5-Fluorouracil (5-FU).

To investigate the prospect for clinical use of novel retinoids YS 904012 and R 9158 in combination with IFN-gamma in inducing differentiation of acute monocytic leukemia.