Biomedical subjects

P He

Publications and source records attributed to P He.

At least 37 records · Page 2Linked to original sources

PubMed2001

Analysis of expressions of components in the plasminogen activator system in high- and low-metastatic human lung cancer cells.

PURPOSE: To determine the expressive patterns of the components of the plasminogen activator system in human large-cell lung carcinoma strains and to analyze the effects of the patterns on tumor invasion and metastasis. METHODS: The in vitro and in vivo invasive and metastatic potential of two human large-cell lung carcinoma strains with high (strain 95D) and low (strain 95C) metastatic potential was further confirmed by the Boyden chamber model and nude mice model. After this, the expressions of the components of the plasminogen activator system--including urokinase-type and tissue-type plasminogen activator (uPA and tPA), urokinase receptor (uPAR), and type-1 and type-2 plasminogen activator inhibitor (PAI-1 and PAI-2) in strain 95D and 95C cells--were determined by RT-PCR and immunohistochemical staining. The effects of monoclonal antibodies of uPA, uPAR, and PAI-1 on the invasive potential of strain 95D cell line were also evaluated. RESULTS: Strain 95D cells were found to have a stronger in vitro and in vivo invasive and metastatic potential than strain 95C cells. In the former, the average number of infiltrating cells in the in vitro model in one field of vision (40055) was 73.75 +/- 7.42, while in the latter, it was 56.33 +/- 6.28 (P < 0.001). Lung metastatic loci were observed in all six nude mice inoculated with 95D cells (6/6), but not in any of the nude mice inoculated with 95C cells (0/6). The high-metastatic strain 95D cells expressed higher uPA and uPAR and lower tPA and PAI-2 than the low-metastatic strain 95C cells. The PAI-1 expressions in both 95D and 95C cells were almost the same. Monoclonal antibodies of uPA and uPAR greatly reduced the invasive potential of strain 95D cells in vitro. CONCLUSIONS: These data suggest that the invasive and metastatic potential of human large-cell lung carcinoma cell lines is associated with differential expressions of the components of the plasminogen activator system and that the determination of these components may be used as a marker for judging clinically the possibility of tumor metastasis as well as the prognoses of patients.

Carcinoma, Large Cell↗

PubMed2001

Simultaneous measurement of sound velocity and wall thickness of a tube.

A method for simultaneously measuring the sound propagation velocity and the thickness of each wall on the opposite sides of a tube is presented. The method uses a pair of ultrasound transducers to produce two reflected pulses from the outer and inner surfaces of the tube wall on the each side, and two transmitted pulses, one with and one without the tube sample between the two transducers. Using the time-domain analysis, sound velocity and wall thickness of the tube are determined from the time delays between the three pairs of ultrasound pulses, whereas using the frequency-domain analysis, phase velocity, group velocity, and wall thickness of the tube are determined from the phase differences between the three pairs of ultrasound pulses. Results of measurements on five tube samples are reported.

Models, Theoretical↗

PubMed2001

Liver injury suppressing compounds from avocado (Persea americana).

To evaluate the protective activity of fruits against liver injury, 22 different fruits were fed to rats with liver damage caused by D-galactosamine, a powerful liver toxin. As measured by changes in the levels of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST), avocado showed extraordinarily potent liver injury suppressing activity. Five active compounds were isolated and their structures determined. These were all fatty acid derivatives, of which three, namely, (2E,5E,12Z,15Z)-1-hydroxyheneicosa-2,5,12,15-tetraen-4-one, (2E,12Z,15Z)-1-hydroxyheneicosa-2,12,15-trien-4-one, and (5E,12Z)-2-hydroxy-4-oxoheneicosa-5,12-dien-1-yl acetate, were novel.

Alanine Transaminase↗

PubMed2001

Electrochemical detection of sequence-specific DNA using a DNA probe labeled with aminoferrocene and chitosan modified electrode immobilized with ssDNA.

The electrochemical detection of sequence-specific DNA using a DNA probe labeled with aminoferrocene (AFC) is reported. Sample ssDNA was immobilized on a chitosan modified glassy carbon electrode. A sequence-known DNA with 256 bp [obtained by polymerase chain reaction (PCR)] was successfully labeled with the electro-active reagent AFC by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide for the first time. This DNA probe labeled with AFC was applied to hybridize with a sequence-unknown DNA sample. Only the complementary sequence (cDNA) could form a double-stranded DNA (dsDNA) with the DNA probe labeled with AFC. The anodic peak currents (ipa) of the AFC bound to the dsDNA by differential pulse voltammetry were used for the determination of cDNA. The ipa of AFC was linearly related to the concentration of cDNA sequence between 1.0 x 10(-8) and 6.0 x 10(-6) mol L-1. The detection limit was 2.0 x 10(-9) mol L-1 using 3 sigma (where sigma is the standard deviation of blank solution, n = 11). The probe showed high sensitivity and selectivity.

Animals↗

PubMed2001

Green tea suppresses lipopolysaccharide-induced liver injury in d-galactosamine-sensitized rats.

We conducted a series of in vivo experiments to clarify the hepatoprotective activity of green tea against lipopolysaccharide (LPS) + D-galactosamine (GalN)-induced liver injury and to elucidate the mechanism by which green tea exerts its effect in 7-wk-old male Wistar rats. Liver injury was assessed by plasma alanine aminotransferase and aspartate aminotransferase activities. Green tea extract significantly suppressed LPS + GalN-induced liver injury when added to the diet (30 or 35 g/kg) and fed to rats for 14 d or when force-fed alone (0.4-1.2 g/kg body) 1.5 h before the injection of drugs. Although all five of the fractions extracted from green tea extract with different organic solvents had significant suppressive effects, the caffeine-containing fraction exhibited the strongest effect, suggesting that the protective effect of green tea against LPS + GalN-induced liver injury is attributable mainly to caffeine. Authentic caffeine also significantly suppressed LPS + GalN-induced liver injury when added to the diet (2 g/kg) and fed to rats for 14 d. Dietary green tea suppressed LPS + GalN-induced apoptosis of liver cells, as assessed by DNA fragmentation. However, dietary green tea did not suppress LPS-induced enhancement of plasma concentration of tumor necrosis factor (TNF)-alpha, the cytokine that is thought to play a pivotal role in the pathogenesis of LPS-induced liver injury, although it significantly suppressed plasma concentrations of interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-10 and interferon (IFN)-gamma. TNF-alpha + GalN-induced liver injury and apoptosis were also suppressed by dietary green tea. In contrast, dietary caffeine significantly suppressed LPS-induced enhancement not only of plasma IL-1beta, IL-6, IL-10 and IFN-gamma concentrations, but also of TNF-alpha concentration. The results suggest that green tea might suppress LPS + GalN-induced liver injury mainly through the inhibition of TNF-alpha-induced apoptosis of hepatocytes, rather than through the suppression of TNF-alpha production, although the suppressed production of TNF-alpha may be associated with the hepatoprotective effect of caffeine.

Alanine Transaminase↗

PubMed2001

Overexpression of Pti5 in tomato potentiates pathogen-induced defense gene expression and enhances disease resistance to Pseudomonas syringae pv. tomato.

The tomato Pti5 gene encodes a pathogen-inducible ethylene response element-binding protein-like transcription factor that interacts with the disease resistance gene product Pto. Overexpression of Pti5 or Pti5-VP16, a translational fusion with a constitutive transcriptional activation domain, in tomato enhanced resistance to Pseudomonas syringae pv. tomato. Constitutive expression of Pti5 or Pti5-VP16 did not affect the basal level of pathogenesis-related gene expression, but it accelerated pathogen-induced expression of GluB and Catalase. The results demonstrate a positive role of Pti5 in defense gene regulation and disease resistance and suggest that a pathogen-activated posttranscriptional regulatory step is necessary for the pathogen induction of the defense gene expression.

DNA-Binding Proteins↗

PubMed2001

Accelerative effect of olive oil on liver glycogen synthesis in rats subjected to water-immersion restraint stress.

The effects of dietary oils on stress-induced changes in the liver glycogen metabolism of male Wistar rats at 6 weeks of age were investigated. The rats were subjected to repetitive water-immersion restraint and fed with a 20% saturated fatty acid mixture (PSC), olive oil (OLI), safflower oil (SAF), or linseed oil (LIS) diet. Stress loading decresed the body weight gain, although the food intake was hardly changed, and the weights of the liver and spleen generally declined regardless of the elapsed time after stress loading and the type of dietary oil. The adrenal weight was generally enhanced by stress in all deitary groups, and particularly tended to be greater in the OLI and PSC groups than in the other two. The plasma corticosterone concentration increased immediately after stressing (Stress-1), but approached the level of the rats with no stress (No stress) 2 h after releasing the stress load (Stress-2) in all groups. The enhancement of corticosterone level in the Stress-1 animals was large in the PSC and OLI groups, and the decline of this level in the Stress-2 animals was small in the OLI group when compared with the other groups. Although the concentrations of total cholesterol (T-CHOL) and triacylglycerol (TG) in the plasma were decreased by stress loading in all groups, these concentrations in the PSC and OLI groups were nearly always higher than in the other groups. The liver serine dehydratase (SDH) activity enhanced by stress was high in the OLI group and tended to be high in the PSC group when compared with the other groups. The contents of liver glycogen were reduced in the Stress-1 animals and extremely elevated in the Stress-2 animals of all groups, and particularly in the OLI group, the reduction in the Stress-1 animals was smaller and the enhancement in the Stress-2 animals was greater than in the other groups. These results suggest that feeding oleic acid to rats exposed to water-immersion restraint further accelerated liver glycogen synthesis through the rise in liver SDH activity due to increased corticosterone secretion when compared with the effect from linoleic and alpha-linolenic acids.

Animals↗

PubMed2001

Suppressive effect of coffee on lipopolysaccharide-induced hepatitis in D-galactosamine-sensitized rats.

A coffee extract significantly suppressed lipopolysaccharide (LPS)-induced hepatitis in D-galactosamine-sensitized rats, as assessed by the plasma alanine and aspartate aminotransferase activities, when it was added to the diet (30 g/kg) and fed to rats for 14 days. Its effect was as strong as that of a green tea extract. The coffee extract suppressed LPS-induced hepatitis when singly force-fed (1.2 g/kg) 1.5 h prior to the injection of the drugs, whereas a decaffeinated coffee extract had no significant effect. The hepatoprotective effect of caffeine was stronger than that of theobromine. These results indicate that coffee can protect animals from LPS-induced hepatitis, and that the effect of coffee might be mainly due to caffeine.

Alanine Transaminase↗

PubMed2001

Hypoglycemic effect of a hot-water extract from defatted sesame (Sesamum indicum L.) seed on the blood glucose level in genetically diabetic KK-Ay mice.

Genetically diabetic (type II) KK-Ay mice, male and 5 weeks of age, were divided into one group of 12 mice that were fed on a basal (BAS) diet and three groups of 6 mice each that were fed on the test diets for 4 weeks. Each test diet contained 4.0% of the hot-water extract (HES) from defatted sesame (Sesamum indicum L.) seed, 1.4% of the water eluent fraction (WFH) of HES or 0.7% of the methanol eluent fraction (MFH) of HES from a glass column packed with HP-20 resin. At the end of the feeding period, the BAS group was divided into the MAL and MALH groups which were respectively force-fed with 1 ml per mouse of a 20% maltose solution in water with or without 4.0% HES. The plasma glucose concentration and amount of urinary excreted glucose were lower from the HES and MFH diets than from the BAS and WFH diets. The levels of plasma glucose and serum insulin were lower in the MALH group than in the MAL group. These results indicate that HES and MFH had a reductive effect on the plasma glucose concentration of KK-Ay mice, and this effect is suggested to have been caused by the delayed glucose absorption.

Age Factors↗

PubMed2001

Suppression of lipopolysaccharide-induced liver injury by various types of tea and coffee in D-galactosamine-sensitized rats.

Extracts of various types of tea and coffee significantly suppressed lipopolysaccharide (LPS)-induced liver injury, as assessed by the plasma enzyme activities, in D-galactosamine-sensitized rats when administered orally once before injecting the drugs. There was a significant negative correlation between the caffeine levels of these extracts and liver injury. Authentic caffeine also had a hepatoprotective effect. These results suggest that caffeine-containing beverages generally suppress LPS-induced liver injury according to their caffeine content.

Alanine Transaminase↗

PubMed2001

Suppressive effect of caffeine on hepatitis and apoptosis induced by tumor necrosis factor-alpha, but not by the anti-Fas antibody, in mice.

Tumor necrosis factor (TNF)-alpha-induced hepatitis and apoptosis, as respectively assessed by serum enzyme activities and hepatic DNA fragmentation were effectively suppressed by a single force-feeding of caffeine (100 mg/kg) 1.5 h before injecting the drug. In contrast, caffeine had no significant effect on anti-Fas antibody-induced hepatitis and apoptosis. These results suggest that caffeine differentially affected TNF-alpha receptor- and Fas-mediated hepatitis and apoptosis.

Alanine Transaminase↗

PubMed2001

Comparative effect of dietary olive, safflower, and linseed oils on spontaneous liver tumorigenesis in C3H/He mice.

In male C3H/He mice, which frequently develop spontaneous liver tumorigenesis, 5 wk of age and weighing about 20 g, the comparative effects on liver tumor incidence from the feeding of olive oil (OLI), safflower oil (SAF), and linseed oil (LIS) diets for 50 wk, the concentrations of total cholesterol (T-CHOL), triacylglycerol (TG), lipid peroxides in the plasma and liver, and the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the plasma were examined. The changes in body weight and liver weight were not different among dietary groups. The number of mice bearing liver adenoma was greater in the SAF group than in the OLI and LIS groups. Liver carcinoma was observed in the SAF group, but not in the OLI and LIS groups. The concentrations of T-CHOL in the plasma and liver were higher in the OLI group than in the other groups. TG levels in the plasma and liver were highest in the OLI group and followed in order by the SAF and LIS groups. The concentration of plasma lipid peroxide was higher in the LIS group than in the other groups. Liver lipid peroxide content was extremely high in the LIS group, medium in the SAF group, and low in the OLI group. The activity of AST was highest in the OLI group and followed in order by the SAF and LIS groups. ALT activity was higher in the OLI group than in the other groups. A positive relationship between spontaneous liver tumorigenesis and the concentrations of T-CHOL, TG, and lipid peroxide or AST and ALT activities was hardly observed. These results suggested that spontaneous tumorigenesis in the liver of male C3H/He mice bred for 50 wk was suppressed by being supplied with OLI and LIS, compared with SAF, which had no direct relation to the concentrations of T-CHOL, TG, and lipid peroxide in the plasma and liver and the activities of plasma AST and ALT.

Adenoma↗

PubMed2001

[QTLs analysis of tiller angle in rice (Oryza sativa L.)].

Tiller angle is one of important characters that constitute plant type with great significance in breading. A pair of japonica/indica lines, which were significantly different in tiller angle, were used in this study. A DH population were constructed via anther culture of F1 hybrids. The tiller angles of 115 DH lines were measured. QTL analysis was conducted based on the constructed molecular linkage map. Three QTLs (qTA-9a, qTA-9b and qTA-12) were detected on chromosome 9 and 12 respectively, Their variation were 22.7%, 11.9% and 20.9% respectively and their additive effects were all negative, showing this character was controlled by genes from big tiller angle parent ZYQ8. The application of the tiller angle that was controlled by major genes and minor genes in rice breeding is also discussed.

Chromosome Mapping↗

PubMed2001

Carcinoma arising in an amputation stump.

We describe a 62-year-old diabetic man who presented with squamous cell carcinoma on his right thigh amputation stump 52 years after the procedure. The potential relationship of the chronic irritation by the artificial leg and the malignant transformation of the healing scar as well as optimal treatment options of scar-tissue carcinomas are reviewed.

Amputation Stumps↗

PubMed2001

[Study of the cytotoxity against human hepatocellular carcinoma cells induced by the MAGE-1 gene modified dendritic cells].

OBJECTIVE: To genetically modify dendritic cells (DC) with a tumor associated antigen gene MAGE-1 and to observe in vitro the cytotoxic effect induced by this genetically modified DC against human hepatocellular carcinoma (HCC) cell line SMMC7721, thus giving a primary verification of the possibility of this genetically modified DC to induce specific antitumor immunity against HCC and serving as a new type of vaccine. METHODS: The MAGE-1 gene was inserted into the retrovirus vector LXSN to construct the recombinant retrovirus LMSN. The monocyte-derived DCs were transfected by LMSN and control virus LXSN respectively as well as a third group was set up as non-transfected control. The MAGE-1 gene expression in LMSN transfected DC was identified by Western blot and the in vitro cytotoxities against SMMC7721 induced by three groups of DC were tested by MTT assay. RESULTS: A recombinant retrovirus LMSN containing the tumor rejection antigen gene MAGE-1 was successfully constructed and the MAGE-1 gene expression in LMSN transfected human monocyte-derived DC was induced. The LMSN transfected DC could induce very high lytic activity against SMMC7721 in vitro with the lytic activity of 78.9%+/-3.6%. Nevertheless, the LXSN transfected DC and non-transfected DC only induced relatively lower lytic activity as 34.7%+/-4.3% and 3.9%+/-2.0%, respectively. The difference of the lytic activities between those three groups as statistically significant (P<0.01). CONCLUSIONS: The MAGE-1 gene transfected DC can induce higher in vitro cytotoxicity against SMMC7721, suggesting the possibility of this genetically modified DC to induce specific antitumor activity and to serve as a new type of vaccine for HCC.

Animals↗

PubMed2001

Reclaimed municipal wastewater--a potential water resource in China.

Due to water resource shortage and socio-economic development within twenty years, China faces serious problems of water supply and water pollution. Several criteria and suitable reclamation processes related to water reuse have been created in China, which are helpful to improve the situation of water scarcity. In the future, reclaimed municipal wastewater reuse will mainly be developed for urban and industrial use. Potential supply quantity of reclaimed water, quality of reclaimed water, and reclamation cost are favorable to potential reuses. Based on further public environmental education, on a relevant development of national and local standards for reclaimed water quality, and on an increase of sanitary rate, more and more planned reclaimed water reuse projects would be expected in China.

Agriculture↗

PubMed2001

[A study of association between atherothrombotic brain infarction and HLA-DQA1 peptide binding motifs].

OBJECTIVE: To analyze the hereditary susceptibility for HLA-DQA1 alleles according to trait of multiple genes leading to disease in atherothrombotic brain infarction (ABI). METHODS: HLA-DQA1 alleles in ABI patients (n=81) and healthy controls (n=99) were detected by PCR-SSP techniques. RESULTS: (1)The frequency of HLA-DQA1*0301 was significantly higher in ABI patients. (2)The frequency of HLA-DQA1*0301 was significantly higher in patients with family history of essential hypertension (EH). (3)The frequency of HLA-DQA1*0103 was significantly lower in ABI patients. CONCLUSION: HLA-DQA1*0301 allele might be a correlative gene with hereditary susceptibility of ABI and HLA-DQA1*0301 allele might be a correlative gene in ABI patients with the family history of essential hypertension, whereas HLA-DQA1*0103 allele might be a protective gene in the patients with ABI.

Aged↗

PubMed2001

[A study on beta-lactamase activity of biofilm Escherichia coli].

OBJECTIVE: To investigate the mechanism of drug resistance of biofilm escherichia coli. METHODS: The model of escherichia coli biofilm was established with the flat-board method. And the biofilm was confirmed by scanning electron microscopy. The beta-lactamase activities were quantitated, in escherichia coli, biofilm escherichia coli, biofilm escherichia coli induced by impenem or cefoxitin. RESULTS: The beta-lactamase activity of biofilm escherichia coli was 2.16 times as much as that of escherichia coli planctonically, and the beta-lactamase activities of biofilm escherichia coli induceded by impenem or cefoxitin were 1.30 and 1.05 times as much as those of biofilm escherichia coli, respectively. CONCLUSION: The drug resistance to antibiotics of biofilm escherichia coli was related to the production of beta-lactamase.

Anti-Bacterial Agents↗