PubMed Health⌕ Search

Biomedical subjects

B Fu

Publications and source records attributed to B Fu.

At least 19 recordsLinked to original sources
PubMed2003

Reciprocal chromosome painting among human, aardvark, and elephant (superorder Afrotheria) reveals the likely eutherian ancestral karyotype.

The Afrotheria, a supraordinal grouping of mammals whose radiation is rooted in Africa, is strongly supported by DNA sequence data but not by their disparate anatomical features. We have used flow-sorted human, aardvark, and African elephant chromosome painting probes and applied reciprocal painting schemes to representatives of two of the Afrotherian orders, the Tubulidentata (aardvark) and Proboscidea (elephants), in an attempt to shed additional light on the evolutionary affinities of this enigmatic group of mammals. Although we have not yet found any unique cytogenetic signatures that support the monophyly of the Afrotheria, embedded within the aardvark genome we find the strongest evidence yet of a mammalian ancestral karyotype comprising 2n = 44. This karyotype includes nine chromosomes that show complete conserved synteny to those of man, six that show conservation as single chromosome arms or blocks in the human karyotype but that occur on two different chromosomes in the ancestor, and seven neighbor-joining combinations (i.e., the synteny is maintained in the majority of species of the orders studied so far, but which corresponds to two chromosomes in humans). The comparative chromosome maps presented between human and these Afrotherian species provide further insight into mammalian genome organization and comparative genomic data for the Afrotheria, one of the four major evolutionary clades postulated for the Eutheria.

Animals↗
PubMed2002

Comparative molecular cytogenetic studies in the order Carnivora: mapping chromosomal rearrangements onto the phylogenetic tree.

We have made a set of chromosome-specific painting probes for the American mink by degenerate oligonucleotide primed-PCR (DOP-PCR) amplification of flow-sorted chromosomes. The painting probes were used to delimit homologous chromosomal segments among human, red fox, dog, cat and eight species of the family Mustelidae, including the European mink, steppe and forest polecats, least weasel, mountain weasel, Japanese sable, striped polecat, and badger. Based on the results of chromosome painting and G-banding, comparative maps between these species have been established. The integrated map demonstrates a high level of karyotype conservation among mustelid species. Comparative analysis of the conserved chromosomal segments among mustelids and outgroup species revealed 18 putative ancestral autosomal segments that probably represent the ancestral chromosomes, or chromosome arms, in the karyotype of the most recent ancestor of the family Mustelidae. The proposed 2n = 38 ancestral Mustelidae karyotype appears to have been retained in some modern mustelids, e.g., Martes, Lutra, Ictonyx, and Vormela. The derivation of the mustelid karyotypes from the putative ancestral state resulted from centric fusions, fissions, the addition of heterochromatic arms, and occasional pericentric inversions. Our results confirm many of the evolutionary conclusions suggested by other data and strengthen the topology of the carnivore phylogenetic tree through the inclusion of genome-wide chromosome rearrangements.

Animals↗
PubMed2001

[Effects of sense and antisense tissue inhibitor metalloproteinase-1 on apoptosis of rat glomerular mesangial cells and its related-gene expressions].

OBJECTIVE: To investigate the role of tissue inhibitor of metalloproteinase-1 (TIMP-1) in apoptosis of rat glomerular mesangial cells (RMC) in vitro. METHODS: TIMP-1 full length cDNA cloned in previous work was used to construct two recombinant plasmids, eukaryotic expression rector, pcDNA3-TIMP-1 (PTs) encoding sense TIMP-1 and pcDNA3-ATIMP-1 (PTas) encoding antisense TIMP-1. These two vectors were then transfected into RMC with lipofectin DOTAP. Northern blotting was used to detect the expression of sense and antisense TIMP-1. Apoptosis was induced in normal RMC, RMC transfected with pCDNA3, PTs and PTas by serum deprivation. Those cells were monitored for apoptosis over extended periods of time (12 h approximately 4 d) by TUNEL and DNA electrophoressis. Furthermore, the expression of apoptosis related-genes was also investigated by RT-PCR. RESULTS: Northern blot analysis and RT-PCR demonstrated that cells transfected with exogenous genes effectively expressed sense or antisense TIMP-1 mRNA. RMC transfected with PTas underwent apoptosis after 12 h of serum deprivation, normal RMC and RMC transfected with pcDNA3 underwent apoptosis after 48 hours in serum-free medium, while RMC transfected with PTs did not undergo apoptosis until 4 days after serum deprivation. Furthermore, TIMP-1 upregulation inhibited expression of bax but had no effect on the expression of bcl-2. CONCLUSION: TIMP-1 suppressed apoptosis of RMC, which suggests a novel activity of TIMP-1 in kidney. Antisense TIMP-1 promotes apoptosis in RMC. The effects of TIMP-1 on RMC apoptosis perhaps correlate with inhibition of bax expression.

Animals↗
PubMed2001

[STAT mediated thrombin induction of tissue inhibitor of metalloproteinase1 in human mesangial cells].

OBJECTIVE: To depict the role of signal transducers and activators of transcription (STAT) pathway in thrombin induction of tissue inhibitor of matrix metalloproteinase-1 (TIMP1) in human mesangial cells. METHODS: Human mesangial cells were isolated, seeded in RPMI1640, and stimulated with thrombin (0.5, 1.5, and 4.5 U/ml). Northern blot and electrophoretic mobility shift assay (EMSA) were employed to determine the levels of TIMP1 mRNA and STAT-DNA binding activity in the cells, respectively. In order to confirm the role of STAT in this cell event, STAT 1 and STAT 3 antisense oligonucleotides were employed to suppress their intra-cellular activity. RESULTS CONCLUSION: Cultured human mesangial cells expressed basal TIMP1 mRNA, and thrombin promoted TIMP1 gene transcription in dose-dependent manner. Hirudin, a specific inhibitor of thrombin, blocked thrombin-induced TIMP1 gene expression. Thrombin promoted STAT DNA binding activity in a manner parallel to TIMP1 mRNA expression, which was inhibited by its inhibitor, hirudin again. STAT1 and STAT3 antisense oligonucleotides inhibited both STAT DNA binding activity and TIMP1 mRNA expression in mesangial cells. CONCLUSION: STAT mediates the thrombin-induced expression of TIMP1 gene in cultured human mesangial cells.

Cells, Cultured↗
PubMed2001

A bis-sesquiterpene and sesquiterpenolides from Inula macrophylla.

Macrophyllidimer C, a novel bis-sesquiterpene, in which the two sesquiterpene units are directly connected by a C-C bond, and eight other sesquiterpenolides were obtained from the bark of Inula macrophylla. Seven of these, macrophyllilactones A-G, are new eudesmanolide- and elemanolide-type sesquiterpenes. Their structures were determined on the basis of spectroscopic evidence and chemical reaction.

Inula↗
PubMed2001

[Quality of aquatic environment at Haihe River and the pollutant fluxes flowing into sea].

On the basis of the data of water quality monitored from 1993 to 1997, the pollution indexes of each pollutant was computed. The results showed that the pollution at Haihe river was severe. The rank of water quality at all monitoring site were between IV and V grade. The main pollution factors were NH3-N, NO2-N and organic contaminants. During the 5 years, water quality of Haihe River was improved, however, the pollutant fluxes flowing into Bohai Bay, especially CODMn, BOD, NH3-N, NO3-N and NO2-N, were increased, they were increased from 1555, 655, 337, 156 and 25 t.a-1 in 1993 to 8710, 4317, 2516, 1528 and 188 t.a-1 in 1996, and sharply decreased to 1331, 973, 572, 355 and 31 t.a-1 in 1997, respectively. It may be mainly due to the change of runoff at Haihe River.

Fresh Water↗
PubMed2001

[Dynamic change and expression of matrix metalloproteinase-2, -9 in alcoholic liver disease in rats].

OBJECTIVE: To evaluate the dynamic change and expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in alcoholic liver disease in rats. METHODS: Alcoholic liver disease rat model was established by gavage. The expression of MMP-2 and MMP-9 was studied by immunohistochemistry, and the result was analyzed by picture quantitative analysis technique. RESULTS: The expression of MMP-2 and MMP-9 was significantly higher in rats of model group than that of control group (P<0.05). The level of MMP-2 and MMP-9 increased gradually with the progress of alcoholic liver disease. Immunoreactive MMP-2 was expressed in endothelial cells of hepatic artery and portal vein, sinusoidal endothelial cells and sinusoidal cells. Immunoreactive MMP-9 was observed in sinusoidal cells and hepatic cells around the vein. CONCLUSIONS: MMP-2 and MMP-9 increa with the progress of alcoholic liver disease. They might be involved in the development of alcoholic liver disease.

Animals↗
PubMed2001

Effect of air abrasion and resin composite on microleakage of Class V restorations bonded with self-etching primers.

PURPOSE: The purpose of this in vitro study was to determine the effect of air-abrasion pretreatment on microleakage of Class V resin composite restorations bonded with self-etching primers. MATERIALS AND METHODS: A total of 54 Class V cavities prepared either with diamond burs or air abrasion (KCP 1000) was restored with resin composites using adhesive systems with self-etching priming agents (Clearfil Liner Bond 2 or Resulcin AquaPrime + Monobond) and thermocycled 2,500 times. The degree of dye penetration (0.5% methylene blue solution) was scored on an ordinal scale at 25X magnification on longitudinally cut sections of the specimens. Wall adaptation at the tooth-restoration interfaces was evaluated under a SEM using replicas of the sectioned teeth. RESULTS: Severe microleakage occurred at the gingival dentinal margins, and less microleakage was detected at the enamel cavity margins. Nonparametrical statistical analysis (H-test) demonstrated no significant differences in microleakage among the different groups. Comparison of dye penetration data and SEM findings showed that with both self-etching priming agents, microleakage occurred in the absence of gaps. CONCLUSION: Use of air abrasion in combination with self-etching priming agents cannot prevent microleakage at the dentin-resin interface of Class V resin composite restorations.

Air Abrasion, Dental↗
PubMed2000

[Effect of thrombin on cell proliferation and plasminogen activator inhibitor type (PAI-1) expression in human embryonic glomerular mesangial cells].

OBJECTIVE: To explore the effect of thrombin on cell proliferation and plasminogen-activator inhibitor Type 1(PAI-1) expression in human embryonic glomerular mesangial cells. METHODS: Methyl-tetragolium (MTT) incorporation, fibrin plate assay and Northern blotting hybridization were used to examine the mesangial cells proliferation, protein activity and mRNA expression of PAI-1 in cultured human embryonic mesangial cells induced by thrombin, respectively. RESULTS: Thrombin enhanced glomerular mesangial cell proliferation, PAI-1 protein activity and mRNA expression in a dose-dependent manner, which could be blocked by hirudin, a specific inhibitor of thrombin. CONCLUSION: Thrombin could enhance mesangial cell proliferation, and up-regulate protein activity and mRNA expression of PAI-1 in cultured human embryonic glomerular mesangial cells. It may play an important role in the pathogenesis of glomerulosclerosis induced by thrombin.

Cell Division↗
PubMed2000

Effects of ICAM-1 antisense oligonucleotide on the tubulointerstitium in mice with unilateral ureteral obstruction.

UNLABELLED: Effects of ICAM-1 antisense oligonucleotide on the renal tubulointerstitium in mice with unilateral ureteral obstruction. BACKGROUND: To extend our previous study of the therapy of the renal lesions of unilateral ureteral obstruction (UUO) in mice by an inhibitor of intercellular adhesion molecule-1 (ICAM-1), we investigated the blocking effects of ICAM-1 antisense oligonucleotides (ASONs) on the ICAM-1 expression in mouse kidney. METHODS: First, ICAM-1 ASON was transducted into mouse renal tubular epithelial cells to investigate the effects of ICAM-1 ASON in vitro. Second, fluorescein isothiocyanate (FITC)-labeled ICAM-1 ASON was injected intravenously to determine the distribution of the ASON in vivo. Third, the expression of ICAM-1 in kidney and the changes of renal morphology were observed to investigate the therapeutic effects of ICAM-1 ASON on the UUO mice in vivo. RESULTS: The expressions of ICAM-1 in the epithelial cells induced by interleukin-1beta were inhibited by ICAM-1 ASON at the dosages of 100 and 200 nmol/L. Twenty-four hours after an introvenous injection with FITC-labeled ICAM-1 ASON, the highest level of fluorescein was detected within the proximal tubules in mouse kidney. Results of immunohistology and Northern blot showed that the ICAM-1 expression was markedly reduced in the obstructed kidney after treatment with ICAM-1 ASON. The ASON also alleviated the infiltration of inflammatory cells and accumulation of the extracellular matrix in the tubulointerstitium of UUO mice without apparent side effects. CONCLUSION: Our data demonstrate that ICAM-1 ASON is taken up primarily by the proximal tubular cells of mouse kidney. ICAM-1 ASON can selectively inhibit the ICAM-1 expression of the renal tubular cells both in vitro and in vivo.

Animals↗
PubMed2000

Identification of monozygotic twins that are concordant for preeclampsia.

Preeclampsia is thought to be discordant in monozygotic twins. While recruiting for a genetic study into preeclampsia, we identified 4 sets of twins and a triplet gestation; all were monozygous on deoxyribonucleic acid "fingerprinting." Two twins were concordant for preeclampsia, and 2 of the triplets had pregnancy-induced hypertension, although only 1 of them had proteinuria. Hence we confirm the existence of monozygotic twins that are concordant for preeclampsia.

Diseases in Twins↗
PubMed2000

New bisabolane sesquiterpenes from Ligularia songarica.

Phytochemical investigation of Ligularia songarica (Compositae) afforded seven new bisabolane-type sesquiterpenes. Their structures were confirmed on the basis of spectroscopic methods, especially 2D-NMR techniques, and compound 7 showed stronger antibacterial activity against Escherichia coli, Pseudomonas acruginosa and Salmonella pullorum.

Anti-Bacterial Agents↗
PubMed2000

Thrombin stimulates MMP-9 mRNA expression through AP-1 pathway in human mesangial cells.

AIM: To investigate the thrombin mediated induction of gelatinase B (MMP-9) in mesangial cells (MC) and the underlying role of activator protein-1 (AP-1). METHODS: Cultured human mesangial cells were exposed to thrombin in the presence or absence of hirudin, curcumin, and c-fos antisense or sense oligonucleotides. Northern hybridization was employed to assess MMP-9 mRNA expression, and electrophoretic mobility shift assay (EMSA) for AP-1 DNA binding activity. RESULTS: The levels of MMP-9 mRNA in the cell treated with different doses of thrombin (500, 1500, and 4500 u/L, respectively) were 1.1, 3.3, and 4.8 times higher than that in the control, respectively. There was also an increase in AP-1 binding activity (3.5, 5.9, and 7.1 fold than that of the control) in accordance with MMP-9 mRNA levels in the presence of thrombin. Hirudin, curcumin, and c-fos antisense oligonucleotides could block thrombin-induced expression of MMP-9 mRNA as well as AP-1 binding activity. CONCLUSION: Thrombin is a potent stimulator of MMP-9 gene expression in human mesangial cells, and the underlying intracellular events are mediated, at least partly, by AP-1 pathway.

Cells, Cultured↗
PubMed2000

[Spatial variability of soil nutrients based on geostatistics combined with GIS--a case study in Zunghua City of Hebei Province].

Geostatistics combined with GIS was applied to analyze the spatial variability of soil nutrients in topsoil (0-20 cm) in Zunghua City of Hebei Province. GIS can integrate attribute data with geographical data of system variables, which makes the application of geostatistics technique for large spatial scale more convenient. Soil nutrient data in this study included available N (alkaline hydrolyzing nitrogen), total N, available K, available P and organic matter. The results showed that the semivariograms of soil nutrients were best described by spherical model, except for that of available K, which was best fitted by complex structure of exponential model and linear with sill model. The spatial variability of available K was mainly produced by structural factor, while that of available N, total N, available P and organic matter was primarily caused by random factor. However, their spatial heterogeneity degree was different: the degree of total N and organic matter was higher, and that of available P and available N was lower. The results also indicated that the spatial correlation of the five tested soil nutrients at this large scale was moderately dependent. The ranges of available N and available P were almost same, which were 5 km and 5.5 km, respectively. The range of total N was up to 18 km, and that of organic matter was 8.5 km. For available K, the spatial variability scale primarily expressed exponential model between 0-3.5 km, but linear with sill model between 3.5-25.5 km. In addition, five soil nutrients exhibited different isotropic ranges. Available N and available P were isotropic through the whole research range (0-28 km). The isotropic range of available K was 0-8 km, and that of total N and organic matter was 0-10 km.

China↗
PubMed2000

[AP-1 mediated signal transduction in thrombin-induced regulation of PAL-1 expression in human mesangial cells].

OBJECTIVE: To evaluate activator protein-1 (AP-1) mediated mechanisms in thrombin-induced qlasminogen activator inhibitor-1 (PAI-1) expression in cultured human glomerular mesangial cells (MCs). METHODS: Electrophoretic mobility shift assay (EMSA) was employed to assess AP-1 DNA-binding activity, and Western blot hybridization was used for quantification of c-fos and c-jun, two subunits of AP-1 dimers. PAI-1 activity and mRNA expression were analysed by the fibrin plate assay and Northern hybridization, respectively. RESULTS: Thrombin concentration enhanced PAI-1 activity in the supernatant and stimulated PAI-1 mRNA expression in cultured MCs. PAI-1 activity was blocked by hirudin, a specific inhibitor of thrombin. Further study demonstrated that thrombin promoted AP-1 DNA-binding activity but exerted little effect on c-fos or c-jun. Curcumin (AP-1 inhibitor), staurosporine (PKC inhibitor), and genistein (PTK inhibitor) all reduced AP-1-mediated PAI-1 mRNA expression induced by thrombin in cultured MCs. CONCLUSION: The present study indicates that in cultured human MCs, thrombin stimulates PAI-1 expression through an AP-1 signal pathway, which may be mediated by PKC and PTK.

Cells, Cultured↗