Role of Pax4 in Pdx1-VP16-mediated liver-to-endocrine pancreas transdifferentiation.

Although Pdx1-VP16 expression induces hepatic cell transdifferentiation into pancreatic precursor cells (WB-1), these incompletely reprogrammed cells fail to become glucose-sensitive insulin-producing cells in the absence of the activation of late-stage pancreatic transcription factors. As Pax4 promotes late-stage beta-cell differentiation and maturation, we generated lentiviral vector (LV) containing mouse Pax4 gene and developed two hepatic cell lines expressing Pax4 in the absence (WB-2 cells) or presence (WB-1A cells) of Pdx1-VP16, via LV-mediated gene transfer. Functional Pax4 protein expression in WB-2 and WB-1A cells was confirmed by electrophoretic mobility shift assay and Pdx1-VP16 protein expression in WB-1 and WB-1A cells was confirmed by Western blotting.

A transgenic rice seed accumulating an anti-hypertensive peptide reduces the blood pressure of spontaneously hypertensive rats.

RPLKPW is a potent anti-hypertensive peptide designed according to the structure of ovokinin(2-7) (RADHPF). In this study, we generated transgenic rice plants that accumulate the RPLKPW peptide as a fusion protein with the rice storage protein glutelin. The engineered peptide is expressed under the control of endosperm-specific glutelin promoters and specifically accumulates in seeds.

[Fermentation and purification of Echistatin fusion protein expressed in Escherichia coli].

Lots of studies of Echistatin (Ecs) have proved its wide use in many aspects. However, the low yield of Ecs has impeded the relative researches of the protein. To establish the high-level expression system of Ecs, the fermentation and purification process of Ecs fusion protein expressed in E.

Derivation of adipocytes from human embryonic stem cells.

Human embryonic stem (hES) cells are undifferentiated and pluripotent cells that hold great therapeutic potential, but are hampered by our limited knowledge to promote specific cell differentiation. Here we provide the first report of the directed differentiation of hES cells into adipocytes. Embryoid bodies (EBs) derived from hES cells are shown to respond to factors that promote adipogenesis.

[Cell-cycle negative regulatory gene ANA is over-expressed in the brain tissues of patients with Down syndrome].

Objective: To investigate the expression level of genes located in chromosome 21 in the brain tissues of Down syndrome(DS).

Methods: An optimized semi-quantitative RT-PCR method was used to evaluate the expression levels of seven genes encoded in chromosome 21 in fetal cortex brain and cerebellum of DS and the control at the end of 20 weeks of gestation. B2M was used as internal reference to normalize cell loss.

Reprogramming liver-stem WB cells into functional insulin-producing cells by persistent expression of Pdx1- and Pdx1-VP16 mediated by lentiviral vectors.

Adenovirus-mediated transient expression of the pancreatic duodenal homeobox transcription factor Pdx1 in mouse liver activates pancreatic endocrine and exocrine genes, the latter reportedly resulting in severe hepatitis. Expression of a super-active form of Pdx1 or Pdx1-VP16 selectively transdifferentiates hepatic WB cells into functional pancreatic beta-like insulin-producing cells, without evidence of exocrine differentiation. No study has systematically compared the transdifferentiation efficiency of Pdx1 and Pdx1-VP16 at the cellular and molecular level.

A rice-based edible vaccine expressing multiple T cell epitopes induces oral tolerance for inhibition of Th2-mediated IgE responses.

Peptide immunotherapy using multiple predominant allergen-specific T cell epitopes is a safe and promising strategy for the control of type I allergy. In this study, we developed transgenic rice plants expressing mouse dominant T cell epitope peptides of Cry j I and Cry j II allergens of Japanese cedar pollen as a fusion protein with the soybean seed storage protein glycinin. Under the control of the rice seed storage protein glutelin GluB-1 promoter, the fusion protein was specifically expressed and accumulated in seeds at a level of 0.

Genetic engineering of human embryonic stem cells with lentiviral vectors.

Human embryonic stem (hES) cells present a valuable source of cells with a vast therapeutic potential. However, the low efficiency of directed differentiation of hES cells remains a major obstacle in their uses for regenerative medicine. While differentiation may be controlled by the genetic manipulation, effective and efficient gene transfer into hES cells has been an elusive goal.

[Preliminary exploration of the influence factors of degenerate oligonucleotide primered PCR of genome DNA].

Objective: To explore the influence factors of the degenerate oligonucleotide primered PCR(DOP-PCR).

Methods: Genome DNA template from the mouse single oocyte or liver tissue were used to perform DOP-PCR. DOP-PCR was carried out with templates of different origin, different gradient dilution, with or without low melting point gel purified to wipe off the small fragment that might interfere with the following analysis, and then PCR of gene FTCD and CBS were carried out to evaluate the influence of these factors on the amplification efficiency and specificity.

Genetically modified rice seeds accumulating GLP-1 analogue stimulate insulin secretion from a mouse pancreatic beta-cell line.

Glucagon-like peptide-1 (7-36) amide (GLP-1) is the most potent physiological insulinotropic hormone in humans. We produced large amounts of a GLP-1 analogue, [Ser8, Gln26, Asp34]-GLP-1, which is resistant to trypsin-digestion, as part of a chimeric rice seed storage protein, a 26 kDa globulin, in genetically modified rice seeds. Junction sites between GLP-1 analogue and globulin were replaced by tryptic cleavage sites.

[Neuropsychiatric symptoms in dementia and elderly people in the community: results from the Beijing Dementia Cooperative Study].

Objective: To determine the prevalence of neuropsychiatric symptoms in dementia and normal elderly people living in the Chinese community of Beijing.

Methods: A cross-sectional study derived from the Beijing Dementia Cooperative Study was carried out a population survey was carried out on a total of 1540 participants aged 65 years and older living in Beijing city and rural areas. All the individuals and 373 demented elderly people completed a series of neuropsychological examination and the Neuropsychiatric Inventory (NPI).

High glucose is necessary for complete maturation of Pdx1-VP16-expressing hepatic cells into functional insulin-producing cells.

Pdx1 has been shown to convert hepatocytes into both exocrine and endocrine pancreatic cells in mice, but it fails to selectively convert hepatocytes into pure insulin-producing cells (IPCs). The molecular mechanisms underlying the transdifferentiation remain unclear. In this study, we generated a stably transfected rat hepatic cell line named WB-1 that expresses an active form of Pdx1 along with a reporter gene, RIP-eGFP.

[The expression profiles of human chromosome 21 orthologues in mouse M II oocyte].

Objective: To analyse the expression profile of orthologues of human chromosome 21 (HC21) in mouse M II oocytes, and to discuss the relationship between this expression profile and early embryonic development and further to find the possible reasons of DS phenotypes genesis.

Methods: cDNA array and Global RT-PCR methods were used to analyse and identify the expression profile of 93 HC21 orthologues in mouse M II oocytes.

Results: 26 of 93 orthologues were proved to be expressed in mouse M II oocytes and these genes were involved in many biological procedure including transcriptional, metabolism, ionic channel, and ubiquitin pathway etc.

In vivo and in vitro characterization of insulin-producing cells obtained from murine bone marrow.

Efforts toward routine islet cell transplantation as a means for reversing type 1 diabetes have been hampered by islet availability as well as allograft rejection. In vitro transdifferentiation of mouse bone marrow (BM)-derived stem (mBMDS) cells into insulin-producing cells could provide an abundant source of autologous cells for this procedure. For this study, we isolated and characterized single cell-derived stem cell lines obtained from mouse BM.

[Detection of thromboxane B2, 6-keto-prostaglandin F1alpha and anticardiolipin antibody in patients with obstructive sleep apnea-hypopnea syndrome].

Objective: To observe the changes of thromboxane B(2) (TXB(2)), 6-keto-prostaglandin F1alpha (6-K-PGF1alpha) and anticardiolipin antibody (ACA) in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) before and after institution of nasal continuous positive airway pressure (nCPAP).

Methods: Sixty cases of OSAHS confirmed by polysomnography (PSG) were selected as the trial group, and 20 normal donors without OSAHS were recruited as the control group. Nineteen patients with severe OSAHS were treated by nCPAP.

DRAQ5-based DNA content analysis of hematolymphoid cell subpopulations discriminated by surface antigens and light scatter properties.

Background: Analysis of cell cycle kinetics offers important information regarding the behavior of normal and neoplastic cells. Most often, cell cycle determinations by flow cytometry (FCM) have been performed using whole-sample analysis with intercalating dyes like propidium iodide (PI). The cell cycle phase assessment in individual cell subsets in heterogeneous samples is best performed using combined antigen/scatter and DNA analysis.

Gene expression profiling during all-trans retinoic acid-induced cell differentiation of acute promyelocytic leukemia cells.

Using cDNA microarrays we determined the gene expression patterns in the human acute promyelocytic leukemia (APL) cell line NB4 during all-trans retinoic acid (ATRA)-induced differentiation. We analyzed the expression of 12,288 genes in the NB4 cells after 12 hours, 24 hours, 48 hours, 72 hours, and 96 hours of ATRA exposure. During this time course, we found 168 up-regulated and more than 179 down-regulated genes, most of which have not been reported before.

[Study on morphology of brain tissue induced by inhale 1,2-dichloroethane].

To study acute toxicity of brain tissue caused by 1,2-dichloroethane (1,2-DCE) under static inhalation. The rats were exposed to 1,2-DCE 12 hours by consecutive static inhalation. The morphology changes of brain were observed on different dose of treated rats.

[Determination of zopiclone in serum by reversed-phase high performance liquid chromatography].

A reversed-phase high performance liquid chromatographic method (external standard method) was developed for the determination of zopiclone in serum. After the selective extraction with n-butyl chloride, this compound was chromatographed on a LiChroCART 125-4 column packed with LiChrospher 60 RP select B(5 microns) using acetonitrile-monopotassium phosphate (20:80, V/V) as mobile phase. The eluting compound was measured by an ultraviolet detector at 254 nm.

All-trans-retinoic acid induces CD52 expression in acute promyelocytic leukemia.

It is well known that all-trans-retinoic acid (ATRA) can induce myeloid cell differentiation in acute promyelocytic leukemia (APL) cells. In this study, we found that ATRA treatment of the APL cell line NB4 induced the expression of CD52, both at transcriptional and translational levels. CD52 is a 21- to 28-kDa nonmodulating cell surface glycosylphosphatidylinositol-linked glycoprotein expressed on lymphocytes and monocytes, but not in human myeloid cells.

In vitro trans-differentiation of adult hepatic stem cells into pancreatic endocrine hormone-producing cells.

Although organ-specific stem cells possess plasticity that permit differentiation along new lineages, production of endocrine pancreas and insulin-secreting beta cells from adult nonpancreatic stem cells has not been demonstrated. We present evidence that highly purified adult rat hepatic oval "stem" cells, which are capable of differentiation to hepatocytes and bile duct epithelium, can trans-differentiate into pancreatic endocrine hormone-producing cells when cultured in a high-glucose environment. These differentiated cells can self-assemble to form three-dimensional islet cell-like clusters that express pancreatic islet cell differentiation-related transcripts detectable by reverse transcription-PCR/nested PCR (e.