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Biomedical subjects

B He

Publications and source records attributed to B He.

At least 73 records · Page 4Linked to original sources
PubMed2000

[The role of membrane-type 1 matrix metalloproteinase in the invasion and metastasis of hepatocellular carcinoma].

OBJECTIVE: To study the role of membrane-type 1 matrix metalloproteinase (MT(1)-MMP) in the invasion and metastasis of hepatocellular carcinoma (HCC), and find a method to judge the invasion and metastasis of HCC through MT(1)-MMP. METHODS: RT-PCR was used to study the expression of MT(1)-MMP mRNA in the HCC and in HCC nude mice model with higher metastasis potential (LCI-D20) and lower metastasis potential (LCI-35), and statistical methods were used to analyse the association between the expression of MT(1)-MMP mRNA and the pathological indexes of HCC. RESULTS: MT(1)-MMP mRNA was expressed by all the normal liver tissue (1.12 +/- 0.73), HCC (3.51 +/- 0.97), surrounding liver parenchyma (1.19 +/- 0.57), tumor embolus, and HCC nude mice model with LCI-D20, LCI-D35. The overexpression of MT(1)-MMP mRNA in HCC, embolus, LCI-D20 was related to the invasion and metastasis of HCC. The expression of MT(1)-MMP mRNA in HCC being higher than that in surrounding liver parenchyma was an important index to judge the invasion and metastasis of the HCC. CONCLUSION: MT(1)-MMP is related to the invasion and metastasis of HCC. The expression of MT(1)-MMP mRNA in HCC being higher than that in surrounding liver parenchyma could be acted as an important index to judge the invasion and metastasis of HCC.

Animals↗
PubMed2000

Arsenic speciation based on ion exchange high-performance liquid chromatography hyphenated with hydride generation atomic fluorescence and on-line UV photo oxidation.

An on-line method capable of the separation of arsenic species was developed for the speciation of arsenite As(III), arsenate As(V), monomethylarsenic (MMA) and dimethylarsenic acid (DMA) in biological samples. The method is based on the combination of high-performance liquid chromatograph (HPLC) for separation, UV photo oxidation for sample digestion and hydride generation atomic fluorescence spectrometry (HGAFS) for sensitive detection. The best separation results were obtained with an anion-exchange AS11 column protected by an AG11 guard column, and gradient elution with NaH2PO4 and water as mobile phase. The on-line UV photo oxidation with 1.5% K2S2O8 in 0.2 mol L(-1) NaOH in an 8 m PTFE coil for 40 s ensures the digestion of organoarsenic compounds. Detection limits for the four species were in the range of 0.11-0.15 ng (20 microL injected). Procedures were validated by analysis of the certified reference materials GBW09103 freeze-dried human urine and the results were in good agreement with the certified values of total arsenic concentration. The method has been successfully applied to speciation studies of blood arsenic species with no need of sample pretreatment. Speciation of arsenic in blood samples collected from two patients after the ingestion of realgar-containing drug reveals slight increase of arsenite and DMA, resulting from the digestion of realgar.

Arsenates↗
PubMed2000

[E-selectin mediates early adhesion of HepG2 hepatoma cells to endothelial cells].

OBJECTIVE: To study the role of E-selectin and sLe(x) in the adhesion between hepatoma cells (HepG2) and endothelial cells, and to select drugs capable of inhibiting such adhesion. METHODS: HepG2 cells were vitally stained with fluorescent dye BCECF-AM. Adhesion between the fluorescent HepG2 cells and human umbilical vein endothelial cells (HUVEC) was examined by solid phase adhesion assay in vitro. A number of agents were tested for their effect on the tumor cell-endothelial adhesion. RESULTS: sLe(x) on the surface of HepG2 cells and E-selectin expressed on the surface of HUVEC were necessary for early adhesion. HepG2 cells could activate HUVEC to increase their adhesiveness to HepG2 cells. Dexamethasone, phenylarsenic oxide, levamisole and actinomycin D were able to block the adhesion between HepG2 to HUVEC at low concentrations. CONCLUSION: sLe(x) and E-selectin are important molecules in the early adhesion of hepatoma cells to HUVEC. Cytokine-like factors of HepG2 origin are likely involved in the activation of endothelial cells in the target tissue. Agents capable of inhibiting NF kappa B can be hopefuly used as anti-adhesion drugs to inhibit metastasis of liver cancer.

Animals↗
PubMed2000

[Photochemical immobilization--a new approach to surface modification of medical polymer materials].

The present paper reviews the approach of surface modification of medical polymer materials-photochemical immobilization. The approach is dramatically different from any other surface modification process available for medical materials. The topics include the principle of photochemical immobilization, the fundamental classification photoreactive groups and the typical applications of photochemical surface modification.

Biocompatible Materials↗
PubMed2000

[Clinical application of the first metacarpal fasciocutaneous flap].

OBJECTIVE: To report the application of the first metacarpal fasciocutaneous flap in repairing digital soft tissue defects. METHODS: The first metacarpal fasciocutaneous flap was designed to repair the lesions of the thumb, index, middle and ring fingers in 14 cases. The blood supply of the flap originates from the branches of the radial pollicis artery at the metacarpophalangeal joint and the venous drainage is to the cephalic vein through the deep pollicis vein and dorsal pollicis vein. RESULTS: All the flaps survived successfully except that one survived partly, two had cyanosis and blister. Followed-up for 3 to 12 months showed the flaps had sensation with good texture and thickness. CONCLUSIONS: The first metacarpal fasciocutaneous flap can be used to repair the lesions of the thumb, index, middle and ring fingers. It has following advantages: 1. reliable blood supply; 2. convenient dissection and 3. less damage of the donor site.

Adolescent↗
PubMed2000

[Experimental study on effect of folium Ginkgo biloba in treating pulmonary interstitial fibrosis in rats].

OBJECTIVE: To evaluate the therapeutic effect and mechanism of folium Ginkgo biloba (FGB) in treating pulmonary interstitial fibrosis (PIF) induced by bleomycin in rats. METHODS: PIF models of bleomycin-A5-induced pulmonary fibrosis were established in rats, they were treated by Bailuda, a preparation of FGB, and the pathological changes, collagen protein level, nuclear factor kB(NF-kB) activity, transforming growth factor beta (TGF-beta) mRNA expression and protein level of the lung tissue were measured. RESULTS: In the Bailuda treated group after treatment, amelioration of the pulmonary alveolitis and fibrosis were shown in pathological section (P < 0.05) and collagen protein content was lesser (P < 0.01) as compared with those in the model control group. After 1 week of Bailuda treatment, the NF-kB activity of pulmonary alveola macrophage lowered by 47.3%, and levels of TGF-beta mRNA expression and protein were all decreased (P < 0.05). CONCLUSIONS: Bailuda has definite effect in treating PIF. The mechanism may be through inhibiting the activity of NF-kB, decreasing TGF-beta mRNA expression and protein, so as to ameliorate the inflammation and fibrosis.

Animals↗
PubMed2000

[Simultaneous pancreas-kidney transplantation for the treatment of type I diabetes with end-stage renal disease].

OBJECTIVE: To demonstrate whether simultaneous pancreas-kidney transplantation is practical for the treatment of Type I diabetes with end-stage renal disease. METHODS: Eight cases of combined pancreas-kidney transplantation were performed in our institute. The age ranged from 35 years to 48 years (average 43.46 years). All cases were diagnosed as type I diabetes with end-stage nephropathy, two cases with blindness due to retinopathy. The case history ranged from 2 years to 22 years. Pancreas allograft was placed in the right iliac fossa with pancreas exocrine drainage to bladder, whereas renal allograft the in left iliac fossa. Initial immunosuppression regimen is quadruple. RESULTS: Seven patient could be insulin free after transplantation, with normal fasting blood glucose. One patient received insulin treatment for 40 days after operation. One patient survived 1 year and 9 months after transplantation with normal functioning pancreas allograft and kidney allograft. Four patient survived 2 months with normal allograft function. Fasting blood glucose was between 4.5 and 6.2 mmol/L; Cr was between 53 and 106 micromol/L. Diet control was not necessary. Two patient died of encephalorrhagia, and 1 pancreatic vascular thrombosis and necrotic pancreatitis. CONCLUSIONS: Combined pancreas-kidney transplantation is feasible to treat type I diabetes with end-stage nephropathy. Functional pancreas allograft could be procured in the present condition. Pancreatic exocrine is drained to bladder. The diagnosis of acute rejection could be made earlier by detecting urine amylase. Heparin should be added in order to prevent pancreatic thrombosis.

Adult↗
PubMed2000

[MMF and CyA in the prevention of early acute rejection after renal transplantation].

OBJECTIVE: To investigate the effect of MMF and low dose CyA on the prevention of early acute rejection after renal transplantation. METHODS: 146 patients with kidney transplantation were analyzed retrospectively from December 1997 to January 1999. These patients were divided into two groups according to the immunosuppressive regimen: Aza group (78 patients) and MMF group (68 patients). All patients met the following criteria: HLA mismatch </= 3 loci, lymphocytes toxicity test < 10%, PRA < 20% for second or third transplantation, warm ischemia time 5-11 minutes, and cold ischemia time 3-24 hours. RESULTS: There were 24 patients with acute rejection episodes (30.77%) in the Aza group; and 10 patients (14.71%) in the MMF group, (P < 0.05). The dosage of CyA and blood concentration of CyA were significantly different; 6.00 +/- 1.21 mg x kg(-1) x d(-1) and 286.00 +/- 20.02 microg/L in the Aza group; 4.00 +/- 1.14 mg x kg(-1) x d(-1) and 204.00 +/- 20.18 microg/L in the MMF group (P < 0.001). CONCLUSIONS: MMF with low dose CyA based triple regimen could prevent the acute rejection episodes effectively at the early period of post transplantation. This triple regimen can reduce the acute rejection episodes by 50%. To some extent, low dose CyA may avoid nephrotoxicity. The long-term effect of this regimen on allograft is still needed to observe.

Adolescent↗
PubMed2000

[The modulating effect of panax pseudoginseng wall saponins on the DAG-PKC signal pathway and TNF secretion of macrophages].

OBJECTIVE: To explore the roles of panax pseudoginseng wall saponins on the DAG-PKC signal pathway and TNF secretion of macrophages. METHODS: The changes of the activities of postburn inositol lipid signal system factors such as PLC, DAG, cytomembrane PKC, cytoplasma PKC, and intracellular calcium concentration and the secretory amount of macrophage TNF were observed. RESULTS: Panax pseudoginseng wall saponins could reduce the increased PLC activity from 57.58 +/- 8.19 to 27.00 +/- 2.31 and the intracellular calcium concentration from 393.18 +/- 392.62 to 90.56 +/- 7.21. With the role of panax pseudoginseng wall saponins, DAG activity reduced from 488.10 +/- 40.20 to 288.30 +/- 30.00, cytomembrane PKC activity decreased from 3081.50 +/- 698.50 to 1699.50 +/- 218.50, and cytoplasmic PKC activity from 2 188.60 +/- 258.30 to 848.40 +/- 138.30. The secretory TNF amount of macrophage decreased by 55%. CONCLUSION: Panax pseudoginseng wall saponins might play an very important role in the modulating of the DAG-PKC signal pathway and decreased TNF secretion of macrophage.

Animals↗
PubMed2000

[A case control study on the levels of lipid, fasting glucose, fasting insulin and sex hormones of hypertension in among elderly Uighur people in Hetian, Xinjiang].

OBJECTIVE: To detect the relationship between the levels of lipid, fasting glucose, fasting insulin, sex hormones and hypertension in the elderly Uighur people in Hetian, Xinjiang. METHODS: A case control study on 105 cases of hypertension was performed, including 58 males and 47 females, aged 60 - 106. RESULTS: Among the lipid analysis items, the decrease of high density lipoprotein-cholesterol (HDL-C) was the important factor related to the occurrence of the complications of hypertension (OR = 5.6214). The increases of both fasting glucose and fasting insulin levels were also risk factors of hypertension in the elderly Uighur people (OR = 2.4474 and OR = 2.5318). CONCLUSION: The risk factors of hypertension in the elderly Uighur people included decrease of HDL-C, high-level fasting glucose and fasting insulin.

Aged↗
PubMed2000

[Mutation of hepatitis B virus DNA pre-C region in patients with primary hepatocellular carcinoma in Guangxi].

OBJECTIVE: To study the association between mutation of hepatitis B virus (HBV) pre-C gene and HBV infection in patients with primary hepatocellular carcinoma (PHC) but negative hepatitis B e antigen (HBeAg) in Guangxi Province, China. METHODS: Nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA Pre C region in sera collected from 16 patients with PHC in Guangxi, and then their HBV DNA nPCR products were sequenced by Sanger method. RESULTS: Sera in fourteen of 16 patients showed positive HBV DNA, with a positive proportion of 87.5% (14/16). One (C23) of them was positive for HBeAg; one (C24) was negative HBeAg, but with normal sequence in his Pre C region; two (C7, C14) were co-infected with HBV wild and mutant strains; and the remainder eight cases (C3, C4, C5, C8, C10, C11, C12, C13) were infected with mutant virus strains, but stop codon at codon 28 was only found in C4, C5 and C12. One case (C8) was co-infected with both HBV stop codon mutant and non-stop codon strains. CONCLUSION: It is uncommon for patients with PHC in Guangxi infected with HBV mutant strain with classical mutation at nt 1 896, which suggests that maybe there exist other types of mutation other than that in pre-C region causing HBV infection without HBeAg.

Base Sequence↗
PubMed1999

Activation function 2 in the human androgen receptor ligand binding domain mediates interdomain communication with the NH(2)-terminal domain.

Activation function 2 in the ligand binding domain of nuclear receptors forms a hydrophobic cleft that binds the LXXLL motif of p160 transcriptional coactivators. Here we provide evidence that activation function 2 in the androgen receptor serves as the contact site for the androgen dependent NH(2)- and carboxyl-terminal interaction of the androgen receptor and only weakly interacts with p160 coactivators in an LXXLL-dependent manner. Mutagenesis studies indicate that it is the NH(2)-/carboxyl-terminal interaction that is required by activation function 2 to stabilize helix 12 and slow androgen dissociation critical for androgen receptor activity in vivo. The androgen receptor recruits p160 coactivators through its NH(2)-terminal and DNA binding domains in an LXXLL motif-independent manner. The results suggest a novel function for activation function 2 and a unique mechanism of nuclear receptor transactivation.

Amino Acid Motifs↗
PubMed1999

Capillary electrochromatography of peptides in a microfabricated system.

Reversed-phase liquid chromatography of tryptic peptides is shown in the capillary electrochromatography mode using microfabricated columns. Although selectivity is different, a mixture of tryptic peptides from ovalbumin appears to be as easily separated in the CEC as HPLC mode. The major difference between a separation in the macrofabricated CEC column and conventional separations in the HPLC mode is that separations are more readily achieved in the isocratic mode in the lower surface area microfabricated CEC columns.

Chromatography, High Pressure Liquid↗
PubMed1999

Microfabricated filters for microfluidic analytical systems.

Solvent and reagent filters were micromachined into quartz wafers using deep reactive ion etching to create a network of intersecting 1.5 x 10 microns channels. When placed at the bottom of reservoirs with a side exit, this channel network behaved as a lateral percolation filter composed of an array of cubelike structures one layer deep. Flow through these filters was driven by electroosmotic flow (EOF). Silanol groups at the walls of channels in the network provided the requisite charge to trigger EOF when voltage was applied laterally to the filter. Adsorption of cationic proteins in this silanol-rich matrix was controlled by the application of a polyacrylamide coating prepared by bonding N-hydroxysuccinimide (NHS)-activated poly(acrylic acid) to (gamma-aminopropyl)silane-derivatized filters. Subsequent reaction of residual NHS groups in the coating with 2-(2-aminoethoxy)ethanol provided channels of low charge density and adsorptivity. These lateral percolation filters were shown to be efficacious in filtering solvents containing a variety of particulate materials, ranging from dust to cells.

Adsorption↗
PubMed1999

Parathyroid hormone-related protein interacts with RNA.

Parathyroid hormone-related protein (PTHrP) is a secreted protein that acts as an autocrine and paracrine mediator of cell proliferation and differentiation. In addition to its biological activity that is mediated through signal transduction cascades, there is evidence for an intracellular role for PTHrP in cell cycle progression and apoptosis. These effects are mediated through a mid-region nuclear targeting sequence (NTS) that localizes PTHrP to the region of the nucleolus where ribonucleoprotein complexes form in vivo. In this work, we show that endogenous, transfected, and in vitro translated PTHrP proteins bind homopolymeric and total cellular RNAs at salt concentrations up to 1 M. A peptide representing the PTHrP NTS was effective in competing with the wild-type protein for RNA binding, whereas a similar peptide representing the nucleolin NTS was not. Site-directed mutagenesis revealed that the binding of PTHrP to RNA was direct and was dependent on preservation of a core GXKKXXK motif, embedded in the PTHrP NTS, which is shared with other RNA-binding proteins. The current observations are the first to document RNA binding by a secreted cellular protein and predict a role for PTHrP in regulating RNA metabolism that may be related to its localization in the nucleolus of cells in vivo.

Amino Acid Sequence↗