Biomedical subjects

P He

Publications and source records attributed to P He.

At least 73 records · Page 4Linked to original sources

PubMed2000

Glycosidic flavonoids as rat-liver injury preventing compounds from green tea.

A glycosidic flavonoids-rich fraction from green tea leaves was purified to isolate five glycosidic flavonoids, guided by the detection of a preventive effect on D-galactosamine-induced liver injury in rats. These were identified as a flavone C-glycoside (1) and trisaccharide flavonols (2-5) based on the spectroscopic analyses. These compounds suppressed the D-galactosamine-induced increase of plasma alanine aminotransferase and asparatate aminotransferase activities in rats.

Animals↗

PubMed2000

[The expression and localization of wild-type p53-GFP fused gene on human high-metastasis hepatocellular carcinoma cell line].

OBJECTIVE: To study the normal expression and location of wt-p53 protein on human high-metastasis hepatocellular carcinoma (HCC) cell line. METHODS: According to the sequence of human wild-type p53, the mp53 cDNA in which stopped codon TGA was mutated to TGG, was amplified by PCR, ligated to EGFP gene, of pEGFP-N1. The recombinant plasmid was transfected into MHCC97, in which p53 gene was mutated. The expression of human p53 protein was observed by fluorescence microscopy. RESULTS: There was a p53 mutation on 249 codon in human high-metastasis hepatocellular carcinoma cell line MHCC97, but no mutation in low-metastasis HCC cells LD20. The two genes of wt-p53 and GFP were fused in codon frame by DNA sequencing. The fluorescence microscopy showed that fluorescence light was spread in all of MHCC97 cells transfected with pEGFP-N1, but fluorescence light was focused on the nucleus of MHCC97 cells transfected with pEGFP-53. CONCLUSION: The p53 mutation on 249 codon may be related to the character of metastasis of HCC cells. The human wild-type p53-GFP fusion protein is expressed in MHCC97 cell line and located in cell nucleus, which is similar to the expression of wt-p53 protein.

Artificial Gene Fusion↗

PubMed2000

The targeted expression of interleukin-2 in human hepatocellular carcinoma cells.

To improve the safety and efficiency of human hepatocellular carcinoma (HCC) gene therapy, we explored the use of a liver-specific promoter and a tumor-specific enhancer to achieve regular IL-2 gene expression for treatment of HCC. The human alpha-fetoprotein (AFP) enhancer [E(AFP)] and the albumin promoter [P(ALB)] were amplified from human genomic DNA. We used eukaryotic expression vector pcDNA-3 for the delivery of the IL-2 gene because this plasmid is a non-transient, fast-selection expression vector. A recombinant plasmid was constructed including the selectable marker neoR gene and the human IL-2 gene derived by the E(AFP) - P(ALB). The liver-predominant expression pattern of the IL-2 gene was observed in the medium of the transfected cells. When human HCC cell lines displaying different levels of AFP and non-hepatocyte tumor cell lines were transfected with the recombinant plasmid, IL-2 was expressed highly in AFP and albumin-positive HCC cells, but low in nonhepatocyte tumor cells. Moreover, the expression level of IL-2 gene was positively proportional to the level of AFP expression in the transfected cells.

Albumins↗

PubMed2000

[Application of microsatellite markers for the seed purity examination of a hybrid rice, Gangyou-22].

For seed commercialization of hybrid rice it is necessary to examine the purity of its seeds before field-production, because the seed purity is closely related to their heterosis performance and yield increase. In this research, 160 microsatellite markers were used for PCR amplification of rice seedling DNAs of Gangyou-22, which is a major hybrid rice in China, and its parents, Gang46A(CMS line) and CDR22(restorer line). A microsatellite marker, RM168, was screened out for its ability to produce polymorphic bands specific to each of the two parents but different from other 22 restorer lines and 9 cultivars. This provides an accurate and efficient method to examine the purity of a hybrid rice at an earlier time. Amplification of DNAs extracted from seeds and application of two microsatellite markers in one PCR system can further simplify the procedure and improve the accuracy of the seed purity examination.

Hybridization, Genetic↗

PubMed2000

[Antitumor activities in vivo of interleukin-12 gene modified dendritic cells in murine models].

OBJECTIVE: To study the antitumor activities of the mIL-12 transfected and acid-eluted peptide sensitized dendritic cells (DC) in murine H22 liver cancer model. METHODS: The murine bone marrow derived DC were transfected with the recombinant adenovirus (Ad mIL-12) containing the mIL-12 gene and control virus AdBGFP. The peptides on the surface of the murine H22 cell line were eluted with mild acid buffer and then sensitized the transfected DC. The experimental animals were immunized with the differently disposed DC and the state of tumorgenesis and tumor growth was observed. RESULTS: The tumor growth and weight in the group immunized with mIL-12 transfected and acid-eluted peptide sensitized DC were significantly lower than those of control group (P<0.05). CONCLUSION: The mIL-12 transfected and acid-eluted peptide sensitized DC can induce obvious antitumor activities in the murine liver cancer models and may suggest new strategies for constructing new type of DC vaccine for liver cancer.

Animals↗

PubMed2000

[A multiparametric monitoring network system based on windows operation system].

This paper introduces the general structure and implementary method both in hardware and software of a monitoring network system, which is developed for monitoring physiological multi-parameter under Windows operation system and based on personal computer. The parameters monitored by the system include Electrocardiogram (ECG), Noninvasive Blood Pressure (NIBP), Oxygen Saturation (SpO2), Respiration (RESP) and Body Temperature. Monitoring data can be shared by internal hospital network. The system has the advantages of easy operation and flexible structure. It is a new kind of hospital monitoring equipment.

Blood Pressure Determination↗

PubMed1999

Chitosan microspheres prepared by spray drying.

Non-crosslinked and crosslinked chitosan microspheres were prepared by a spray drying method. The microspheres so prepared had a good sphericity and a smooth but distorted surface morphology. They were positively charged. The particle size ranged from 2 to 10 micron. The size and seta potential of the particles were influenced by the crosslinking level. With decreasing amount of crosslinking agent (either glutaraldehyde or formaldehyde), both particle size and zeta potential were increased. Preparation conditions also had some influence on the particle size. DSC studies revealed that the H2 antagonist drug cimetidine, as well as famotidine was molecularly dispersed inside the microspheres, in the form of a solid solution. The release of model drugs (cimetidine, famotidine and nizatidine) from these microspheres was fast, and accompanied by a burst effect.

Biocompatible Materials↗

PubMed1999

Gender difference in dopamine concentration and postischemic neuronal damage in neostriatum after unilateral dopamine depletion.

Most neurons in the dorsal neostriatum die 1 day after 30 min of cerebral ischemia. Dopamine may play a role in the pathogenesis of neuronal injury in neostriatum following ischemia. It has been shown that the number of surviving neurons in the right neostriatum dramatically increased following ischemia after lesions were made in the right substantia nigra (SN), whereas no such protective effect was observed in the left neostriatum after left SN lesion. Using a voltammetric technique, the present study measured the dopamine concentration in neostriatum during ischemia after unilateral dopamine depletion and correlated it with the postischemic neuronal damage in neostriatum of male and female rats. In both genders, dopamine concentrations in the neostriatum of the intact side increased to 50-60 microM during ischemia while those of the lesion side were 15-30 microM. No difference in dopamine concentration was detected between animals with lesions in the left SN and those with lesions in right SN. In male rats, the number of surviving neurons in the right neostriatum (approximately 80% as control) was significantly greater than that in the left neostriatum (approximately 20%) after ipsilateral dopamine depletion, whereas in female animals, the number of surviving neurons in the right neostriatum (approximately 40%) was about the same as that in the left neostriatum (approximately 35%) after dopamine depletion. These results indicate that the asymmetry in ischemic outcome after unilateral dopamine depletion in male rats is not due to the difference in residual dopamine in neostriatum. The lateralization of D2 receptors in male rats may be responsible for the asymmetry of survivability of striatal neurons after transient forebrain ischemia.

Animals↗

PubMed1999

Analyses of proteins involved in vesicular trafficking in platelets of mouse models of Hermansky Pudlak syndrome.

Hermansky Pudlak syndrome (HPS) is an autosomal recessive inherited disorder characterized by defects in synthesis and/or secretion of three related subcellular organelles: melanosomes, platelet-dense granules, and lysosomes. In the mouse, mutant forms of any of 14 separate genes result in an HPS-like phenotype. The mouse pearl and mocha genes encode subunits of the AP3 adaptor protein complex, confirming that HPS mutations involve proteins regulating intracellular vesicular trafficking. Therefore, expression of several additional proteins involved in vesicular transport was examined by immunoblotting of platelet extracts from HPS mutant and control mice. Platelet levels of SCAMPS (secretory carrier membrane proteins), Rab11, Rab31, NSF (N-ethylmaleimide-sensitive fusion protein), syntaxin 2, syntaxin 4, munc18c, and p115/TAP (p115/transcytosis-associated protein) were not significantly altered in several different HPS mutants. However, gunmetal (gm/gm) platelets contained decreased amounts of SNAP-23. The Snap23 gene was mapped to mouse chromosome 5, demonstrating it cannot encode the gm gene, which maps to chromosome 14. It is likely therefore that the gm gene functions upstream of SNAP-23 in vesicular trafficking.

Albinism, Oculocutaneous↗

PubMed1999

Allele frequencies of eight STRs in Japanese and Chinese.

Allele frequencies for the eight STR loci Hum-CSF1P0, F13A01, F13B, FES/FPS, LPL, TH01, TPOX and VWA were investigated in Japanese and Chinese populations. No significant deviations from Hardy-Weinberg equilibrium could be found for all loci. In the Japanese population VWA, CSF1PO, TH01, FES/FPS and TPOX were found to be useful for forensic applications and in the Chinese population, VWA, CSF1PO, TH01 and TPOX were found to be useful. Allele distributions were similar between both populations except for FES/FPS.

Alleles↗

PubMed1999

The targeted expression of the human interleukin-2/interferon alpha2b fused gene in alpha-fetoprotein-expressing hepatocellular carcinoma cells.

This study explores the use of a liver-specific albumin promoter and a tumor-specific alpha-fetoprotein (AFP) enhancer to achieve the regulated expression of the cytokine interleukin-2/interferon alpha2b (IL-2/IFNalpha2b) fused gene for treatment of hepatocellular carcinoma (HCC). The human AFP enhancer (E(AFP)) and albumin promoter (P(ALB)) were amplified from human chromosome DNA by the polymerase chain reaction. A recombinant retrovirus was constructed including, as a selectable marker, the neoR gene and the IL-2/IFNalpha2b fused gene controlled by E(AFP)-P(ALB). The liver-targeted expression pattern of the IL-2/IFNalpha2b fused gene was observed when this product was tested in the culture medium of the infected cells (IL-2 activity was 850 IU/10(6) cells, IFNalpha activity was 320 IU/10(6) cells). Moreover, The growth of the IL-2/IFNalpha2b-fused-gene-infected HCC cells, SMMC7721, was clearly suppressed by the second week after innoculation of nude mice compared to the control SMMC7721 cells infected with LXSN and untreated SMMC7721 cells (0.5 +/- 0.1 cm versus 1.4 +/- 0.2 cm and 1.6 +/- 0.2 cm, P < 0.05). The results showed that the combined transcriptional regulatory sequences of E(AFP)-P(ALB) could control the targeted expression of cytokine genes in AFP-positive human HCC cells, and the expression level of the IL-2/IFNalpha2b fused gene was positively correlated to the level of AFP expression in the infected cells. The IL-2/IFNalpha2b fused protein that was expressed has the functions of both IL-2 and IFNalpha. Therefore, this study illustrates the superiority of using transcriptionally targeted recombinant retrovirus vectors in cytokine-based gene therapy.

Albumins↗

PubMed1999

MAGE-1 and related MAGE gene expression may be associated with hepatocellular carcinoma.

PURPOSE: The possibility of tumor rejection antigen, encoded by the MAGE-1 gene, being a target for immunotherapy in hepatocellular carcinoma (HCC) patients and the cloning of the full-length cDNA of this gene for subsequent studies were explored with the aim of discovering new immunotherapeutic strategies for HCC. METHODS: Expression of the MAGE-1 gene in HCC specimens and HCC cell lines was examined by the reverse transcription/polymerase chain reaction (RT-PCR) with a pair of specific primers, which gave a 421-bp fragment. Another pair of primers were then used to amplify the full-length MAGE-1 cDNA by the same method. The PCR products were then digested by restriction endonucleases and inserted into the plasmid PUC19. After primary selection of the recombinants by endonuclease digestion, the sequences of the inserted gene fragments were confirmed by DNA sequence analysis. RESULTS: In 45 HCC patients, MAGE-1 mRNA was expressed in 27 tumor tissues (60%) and 5 paratumor tissues (11.1%). All the four HCC cell lines positively expressed the MAGE-1 gene. Owing to the high homology of the MAGE gene family, we obtained three clones of different MAGE genes using the same pair of cloning primers. The three clones were confirmed to be a full-length MAGE-1 gene, a 750-bp fragment of the MAGE-3 gene and a fragment highly homologous to MAGE-6 and MAGE-12 but not identical to any known MAGE genes. CONCLUSION: The high expression frequency of MAGE-1 gene in HCC suggests the possibility of using it as a target for immunotherapy in HCC patients. Some MAGE genes other than MAGE-1 may also be expressed in HCC together with an unknown MAGE gene that might introduce new targets for immune attacks. The three gene clones obtained in this study can be used in further investigations and especially in the development of new liver cancer vaccines.

Amino Acid Sequence↗

PubMed1999

Teas and other beverages suppress D-galactosamine-induced liver injury in rats.

We compared the effects of various types of beverages (teas, coffee, and cocoa) on D-galactosamine-induced liver injury by measuring plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in 7-wk-old male Wistar rats. The effects of five fractions extracted with different organic solvents from green tea, different types of dietary fibers, and some short chain fatty acids were also investigated. All of the beverages tested significantly suppressed D-galactosamine-induced enhancement of plasma enzyme activities when powdered beverages were added to the diet (30 g/kg) and fed to rats for 2 wk. Plasma ALT activities were 1155 +/- 82 [micromol/(min.L), control], 289 +/- 61 (green tea), 626 +/- 60 (roasted green tea), 471 +/- 84 (puerh tea), 676 +/- 69 (oolon tea), 423 +/- 76 (black tea), 829 +/- 53 (coffee), and 885 +/- 89 (cocoa). The profile of AST activities was similar. The caffeine-containing fraction from green tea had no significant effect, whereas the other four fractions, including the soluble fiber fraction, significantly suppressed liver injury. In addition to tea fibers, many other types of dietary fiber (hemicellulose, chitin, chitosan, alginate, pectin, guar gum, glucomannan, and inulin, but not cellulose) had liver injury-preventive effects when added to the diet (30 g/kg), suggesting that liver injury-prevention may be one of the general effects of dietary fibers. Of three short-chain fatty acids tested (acetate, propionate, and butyrate), only acetate prevented liver injury when added to the diet (15 g/kg), supporting the possibility that the liver injury-preventive effect of dietary fibers may be mediated at least in part by certain organic acids. These results suggest that several beverages possess preventive effects on certain types of liver injury, such as that induced by D-galactosamine, and that different constituents of high and low molecular weights contribute to the liver injury-preventive effects of green tea.

Alanine Transaminase↗

PubMed1999

Role of alpha-SNAP in promoting efficient neurotransmission at the crayfish neuromuscular junction.

In this manuscript, we address the role of the soluble N-ethylmaleimide sensitive factor attachment protein (alpha-SNAP) in synaptic transmission at the neuromuscular junction of the crayfish opener muscle. Immunochemical methods confirm the presence of alpha-SNAP in these preparations and show that it is concentrated in the synaptic areas. Microinjection and electrophysiological studies show that alpha-SNAP causes an increase in neurotransmitter release yet does not significantly affect the kinetics. More specific quantal analysis, using focal, macropatch, synaptic current recordings, shows that alpha-SNAP increases transmitter release by increasing the probability of exocytosis but not the number of potential release sites. These data demonstrate that the role of alpha-SNAP is to increase the efficiency of neurotransmission by increasing the probability that a stimulus will result in neurotransmitter release. What this suggests is that alpha-SNAP is critical for the formation and maintenance of a "ready release" pool of synaptic vesicles.

Animals↗

PubMed1999

Suppression of D-galactosamine-induced rat liver injury by glycosidic flavonoids-rich fraction from green tea.

Tea constituents that had a preventive effect on D-galactosamine-induced liver injury in rats were partially purified by column chromatography from a n-butanol-soluble fraction of green tea. The fraction containing glycosidic flavonoids was found to suppress the D-galactosamine-induced increase of plasma alanine aminotransferase and aspartate aminotransferase activities. These results indicate that glycosidic flavonoids contribute, at least in part, to the liver injury-preventive effect of green tea.

Alanine Transaminase↗

PubMed1999

Postnatal limb bone growth in relation to live weight in pigs from birth to 84 days of age.

Long limb bones were dissected from 30 Camborough x Canabrid pigs serially slaughtered at birth, 14, 28, 56, and 84 d of age to determine the growth patterns of long limb bones (humerus and radius for the forelimb and femur and tibia for the hindlimb) in relation to live weight from birth to 84 d of age, weighing up to approximately 31 kg. Relationships between individual long limb bone measurements (Y) and live weight or transformations of live weight (X) were evaluated using allometric analyses. Hindlimb bones tended to have higher growth coefficients than forelimb bones (P < .05), suggesting an anterior-posterior gradient of long limb bone growth. However, centripetal gradients of growth for long limb bones were not evidential (P > .05). Greater diameter growth compared with length growth of the long limb bones indicated that the differentiation in growth for diameter and length of the long limb bones was an effective response to the functional requirements of standing, walking, and running following birth.

Animals↗

PubMed1999

[Expression of MAGE-1 gene in hepatocellular carcinoma].

OBJECTIVE: To explore the possibility of tumor associated antigen encoded by MAGE-1 gene used as a target for immunotherapy in HCC patients. METHOD: The expression of MAGE-1 gene in 39 HCCs and 3 HCC cell lines and 5 non-HCC patients liver tissues was examined by RT-PCR method. RESULTS: The expression rate of MAGE-1 mRNA was significantly higher in HCC patients than in paratumor tissues (P < 0.01, 58.9% vs 10.3%). All the 3 HCC cell lines expressed MAGE-1 gene positively. All 5 non-HCC patients' liver tissues did not express MAGE-1 gene. CONCLUSION: The high frequency of expression of MAGE-1 gene in HCCs suggests the possibility of MAGE-1 used as a target for immunotherapy in HCC patients.

Adult↗

PubMed1999

Test of a vertical scan mode in 3-D imaging of residual limbs using ultrasound.

We have developed a new ultrasound system for imaging residual limbs that employs two scan modes: a vertical scan mode (VSM) primarily used for capturing the skin surface, and a horizontal compound scan mode (HCSM) primarily used for imaging the internal tissue structures. Since the HCSM was described previously (J Rehabil Res Dev 1997;34(3):269-78), the main purpose of this article is to elucidate the principle of reconstructing the skin surface using the new VSM and to report the accuracy of volumetric measurement based on this reconstruction method. For a residual limb with a length of up to 26 cm, the vertical scan takes about 80 s. The acquired skin surface has a resolution of 144 points per circumference in the transverse direction and a resolution of 28 points per cm in the longitudinal direction. The measurement accuracy of the system is tested using a cylindrical phantom and a custom-made limb model. The diameter of the phantom measured by the ultrasound method is 113.8 +/- 0.23 mm, compared with a value of 113 mm measured by a caliper. For the limb model, cumulative segment volumes measured by the ultrasound method are compared with those measured by the hydrostatic weighing method. The relative errors are <1%. This study demonstrates the feasibility of using ultrasound to perform limb measurement for prosthetic CAD/CAM applications.

Artificial Limbs↗