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Min Zheng

Publications and source records attributed to Min Zheng.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Analyzing differentially expressed genes in the brain of rat exposed to mercury chloride using cDNA microarray].

This study is to determine differentially expressed genes in the brain of rat exposed to mercury chloride and investigate the molecular mechanism of mercury neurotoxicity using cDNA microarray. The experimental group of rats were treated with 0.5 mg/kg weight of mercury chloride via hypodermic injection. The differentially expressed genes in rat brains after I h of injection were scanned by the cDNA microarray. The gene expression profiles show that there are 742 genes, in which 562 are upregulated and 180 are downregulated. Further analysis by bioinformatic technique disclosed that the differentially expressed genes were involved in many biological processes, which included immuno-response and detoxifcation, transfer and expression of genetic information, cell signalling, neurotransduction, cell proliferation and cell differentiation, apoptosis, etc. The result of analysis indicated these genes might be related to the neurotoxicity of mercury. The investigation of differentially expressed genes using cDNA microarray provides a new approach to further disclose the neurotoxic mechanism of mercury.

Animals↗
PubMed2006

[Effect factors for mercury accumulation to natural surface coatings and analysis its forms of occurrence].

In order to probe to the factors for mercury accumulation to natural surface coating, we study the concentration of mercury in Huangpu River surface coatings developed for different depth, different grown days and different seasons and analysis mercury forms of occurrence. The result show the organic matter in biofilm is much high (7.5%-14.5%). Growth time, depth and seasons are all important factors for mercury accumulation to surface coating. Illumination and temperature was stronger and the growth day was longer, The concentration of mercury in biofilm was higher. The mercury forms of occurrence in surface coating were mainly residual matter bound mercury (41.98%) and organic acids bound mercury (27.89%). The percentage of carbonate bound mercury (10.17%) and ion exchangeable mercury (5.33%) was little.

Biofilms↗
PubMed2006

ZD7288 inhibits the synaptic transmission in the pathway from perforant pathway fibers to CA3 region in rat hippocampus.

AIM: To study the effect of ZD7288 on synaptic transmission in the pathway from perforant pathway (PP) fibers to CA3 region in rat hippocampus. METHODS: The extracellular recording technique in vivo was used to record the CA3 region field potentials. High-performance liquid chromatography (HPLC) with fluorescence detection was applied to measure the content of amino acids in hippocampal tissues. The effect of ZD7288 and CsCl on the amplitudes of population spike (PS) in CA3 region evoked by stimulation (0.5 Hz) of the perforant pathway (PP) fibers, and the content of amino acids in hippocampal tissue were observed. RESULTS: Microinjection of ZD7288 (20, 100 and 200 nmol) and CsCl (1, 5 and 10 micromol) into CA3 region decreased the population spike (PS) amplitudes in a dose-dependent manner. The inhibitory effects appeared at 5 min after microinjection and lasted at least 90 min. In those rats treated with ZD7288 (100 nmol), the contents of glutamate, aspartate, glycine and GABA decreased significantly as compared to those of saline control (all P < 0.01, except P < 0.05 for that of glycine). A similar decrease in the contents of amino acids was observed when the rats were microinjected with CsCl (5 micromol). CONCLUSION; ZD7288 could obviously inhibit synaptic transmission in the pathway from PP fibers to CA3 region in rat hippocampus, and this action of ZD7288 may be associated with altered contents of amino acids.

Amino Acids↗
PubMed2006

[Effect of combined therapy of modified kangjia recipe combined with western medicine on hyperthyroidism].

OBJECTIVE: To observe the therapeutic effect of combined therapy of modified Kangjia Recipe (KR) and western medicine propylthiouracil (PTU) on hyperthyroidism and to assess its advantage. METHODS: Ninety patients with hyperthyroidism were divided into the treatment group (TG) and the control group (CG). The 60 patients in TG treated with KR and PTU, and the 30 patients in CG treated with PTU alone. The treatment course of both groups was 3 months. The serum thyroid hormone (TH) level, clinical symptoms and signs, and adverse reaction were observed before and after treatment. RESULTS: The serum TH level, clinical symptoms and signs were significantly improved after treatment in both groups (all P < 0.01). The total effective rate was 93.3% in TG, which was higher than that in CG (83.3%, P < 0.01); and the efficacy in improving palpitation, fidget, aversion to heat, sweating and insomnia was better in the TG than that in the CG respectively (P < 0.05). As for the incidence of adverse reaction, it that was lower in the TG than in the CG. CONCLUSION: KD has good efficacy in treating hyperthyroidism, and the combined treatment of Chinese and Western medicine shows obvious advantages.

Adult↗
PubMed2006

Expression of c-fos and oxidative stress on brain of rats reared on food from mercury-selenium coexisting mining area.

Wanshan mercury mine is the largest mercury deposit in Guizhou Province of China, but there were few reports on mercury toxic effect in the mining area. In order to study the neurotoxicity of food from Wanshan mercury mine area and probe into the effect of food from Wanshan mercury miner area on the changes of brain oxidative damage and expression of c-fos gene. The rats were exposed to mercury contaminated food for 20 d. The content of malondialdehyde (MDA), superoxide dismutase (SOD), GSH-peroxidase (GSH-px) and Glutathione (GSH) in rat brain was measured, and the effect of mercury contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods. The results showed the levels of GSH, MDA, SOD and of GSH-dependent enzymes in the rat brain changed between exposure groups and control group; The mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group (P<0.01). It could be concluded that oxidative stress signals could contribute to the induction of immediate early genes (IEGs); free radicals and their by-products might not only cause oxidative damage, but also influenced gene expression; IEGs c-fos participated in the toxicity process of brain injury by mercury polluted food.

Animals↗
PubMed2005

Determination of serum levels of YKL-40 and hyaluronic acid in patients with hepatic fibrosis due to schistosomiasis japonica and appraisal of their clinical value.

The objectives of this study were (i) to evaluate the serum levels of human cartilage glycoprotein 39 (YKL-40) and hyaluronic acid (HA) in people infected with Schistosoma japonicum, and (ii) to determine their clinical value. A total of 563 people were subjected to ultrasonography, and 60 patients were identified with either mild (n=30) or severe (n=30) hepatic fibrosis. In addition, 28 healthy subjects were included as controls. Blood sera of these 88 people were examined with regard to the levels of YKL-40 and HA. The former was measured by enzyme-linked immunosorbent assay, and serum HA was determined by a commercially available radioimmunoassay method. On the basis of the ultrasonographic investigations, HA levels in normal, mild, and severe cases of hepatic fibrosis were 83.0+/-35.7, 216.1+/-77.9 and 212.6+/-80.9 microg/ml, respectively. When the same sera were tested for YKL-40, 49.0+/-10.4, 92.3+/-18.5 and 172.1+/-35.9 microg/ml, respectively, were recorded in the three groups. Thus, the serum levels of YKL-40 are not only increased in patients infected with S. japonicum but they are also correlated with the stage of hepatic fibrosis. In conclusion, it appears that YKL-40 is more sensitive than HA in measuring the degree of hepatic fibrosis due to schistosomiasis, which warrants further investigation.

Adipokines↗
PubMed2005

[Screening of a hepatic stellate cells subtracted cDNA library of differentially expressed genes in mice with schistosomiasis japonica].

OBJECTIVE: To construct and screen a hepatic stellate cells(HSCs) subtracted cDNA library, in order to seek differentially expressed genes in mice infected with Schistosoma japonicum. METHODS: HSCs were isolated from mouse as targets, and cDNA fragments of normal mouse were compared to those of S. japonicum infected mice to find dif ferentially expressed genes by technique of suppression subtractive hybridization(SSH). Differentially expressed cDNA fragments were then directly inserted into T/A cloning vector to set up the subtractive library. Amplification of the library was carried out with transformation of DH5alpha. A subtracted cDNA library was constructed and then hybridized with forward and backward subtracted probes for differential screening. One hundred positive bacterial clones were randomly selected for se quenching and BLAST analysis. Finally, virtual Northern blot confirmed such differential expression. RESULTS: The amplified library contained more than 400 positive bacterial clones. Random analysis of 100 clones with restriction enzyme digestion showed that all clones contained 200-600 bp inserts. 76 ESTs were obtained with 70 related to fibrosis caused by schistosomiasis or other etiological factors. Other 6 ESTs were not found in PubMed. CONCLUSION: The subtracted cDNA library of differentially expressed genes of HSC in normal mice and schistosome-infected mice was constructed successfully with SSH and T/A cloning techniques.

Animals↗
PubMed2005

Conservation and diversification of Wnt signaling function during the evolution of nematode vulva development.

Cell-fate specification and cell-cell signaling have been well studied during vulva development in Caenorhabditis elegans and provide a paradigm in evolutionary developmental biology. Pristionchus pacificus has been developed as a 'satellite' organism with an integrated physical and genetic map that allows detailed comparisons to C. elegans. A common aspect of vulva formation in both species is the polarization of the P7.p lineage, which is responsible for vulval symmetry. In C. elegans, Wnt signaling is crucial for P7.p cell-fate patterning; nothing is known about vulval symmetry in P. pacificus. We isolated mutations that disrupt polarization of the P7.p lineage in P. pacificus and found that the corresponding gene encodes a Frizzled-like molecule. In addition, mutations in Ppa-lin-17 (encoding Frizzled) and morpholino knock-down of Ppa-lin-44 (encoding Wnt), Ppa-egl-20 (encoding Wnt), Ppa-mig-5 (encoding Dsh), Ppa-apr-1 (encoding APC) and Ppa-bar-1 (encoding beta-catenin) results in gonad-independent vulva differentiation, indicating that these genes have a role in a negative signaling process. In contrast, in C. elegans, Wnt signaling has a positive role in vulva induction, and mutations in bar-1 result in a hypoinduced phenotype. Therefore, whereas the molecular mechanisms that generate vulval symmetry are conserved, the genetic control of vulva induction diversified during evolution.

Amino Acid Sequence↗
PubMed2005

Bradykinin potentiates 5-HT3 receptor-mediated current in rat trigeminal ganglion neurons.

AIM: To explore the modulatory effect of bradykinin (BK) on 5-HT(3 )receptor-mediated current in trigeminal ganglion (TG) neurons in rats. METHODS: The whole-cell patch-clamp technique was used to record 5-HT-activated currents (I(5-HT)) in neurons freshly dissociated from rat TG. Drugs were applied by rapid solution exchange. RESULTS: The majority of the neurons examined responded to 5-HT applied externally with an inward current (76.3%, 74/97) that could be blocked by the 5-HT(3 )receptor antagonist, ICS-205,930 (10(-6) mol/L). In 66 of the 74 cells sensitive to 5-HT (89.2%), pretreatment for 30 s with BK (10(-6)-10(-10) mol/L) could potentiate I(5-HT) with the maximal modulatory effect occurring at 10(-7) mol/L BK (71.6%+/-4.9%). BK shifted the 5-HT concentration-response curve upwards with an increase of 68.9%+/-7.2% in the maximal current response, but with no significant change in the EC(50) value (19.1+/-3.2 mumol/L vs 20.9+/-3.5 micromol/L; t-test, P>0.05; n=8). BK potentiated I(5-HT) in a holding potential-independent manner and did not alter the reverse potential of I(5-HT). This BK-induced potentiation of I(5-HT) was almost completely blocked by Hoe 140 (5*10(-7) mol/L), a selective B2 BK receptor antagonist, and was removed after intracellular dialysis of GF-109203X (2 micromol/L), a selective protein kinase C (PKC) inhibitor, with the re-patch clamp. CONCLUSION: Pre-application of BK exerts an enhancing effect on I(5-HT) via a PKC-dependent pathway in rat TG neurons, which may explain the peripheral mechanism of pain and hyperalgesia caused by, for example, tissue damage and inflammation.

Animals↗
PubMed2005

Construction of a hepatic stellate cells subtracted cDNA library of differentially expressed genes in normal mice and mice with Schistosomiasis japonica.

To construct a hepatic stellate cells (HSCs) subtracted cDNA library to find differentially expressed genes in normal mice and mice infected with Schistosoma japonicum (S. japonicum). Suppression subtractive hybridization (SSH) was used. The cDNA fragments of normal mouse were compared to those of schistosoma-infected mice to find differentially expressed genes. Then differentially expressed cDNA fragments were directly inserted into T/A cloning vector to set up the subtractive library. Amplification of the library was carried out with transformation of DH5alpha. The amplified library contained more than 400 positive bacterial clone, which were then hybridized with forward and backward subtracted probes for differential screening. One hundred positive bacterial clones were randomly selected for sequencing and BLAST analysis. Finally, virtual Northern Blot confirmed such differential expression. The subtracted cDNA library of differentially expressed genes of HSCs was constructed successfully, the library is efficient and lays foundation for screening and cloning new and specific genes of schistosomiasis.

Animals↗
PubMed2005

[Expression of c-FOS protein in rat hippocampus by inducing of mercury contaminated rice].

In order to probe into the biological effects of mercury in typical mercury contaminated area and try to apply the expression of immediately early gene c-fos in brain to early predict the neurotoxicity of mercury in typical polluted areas, the expression of c-FOS protein in rat hippocampus is observed using immunocytochemical methods. The results show the mercury pollutes rice induced significantly the expression of c-FOS protein in hippccampus;the antagonisis between selenium and mercury on the exposure process. It is suggested that c-fos can be used as an effective index of detecting and assessing neurotoxicology of mercury polluted areas.

Animals↗
PubMed2005

[Effects of artificial tending on Pinus tabulaeformis forest growth and its structural characteristics].

The investigation on the growth status, community composition, and structural characteristics of Pinus tabulaeformis forest artificially tended for six years showed that there were significant differences in the average DBH, height, and crown size of the forest among the treatments DA (trimming without intermediate cutting), FA (trimming and intermediate cutting) and CK (without trending). Treatment FA had the highest values of average DBH (7.8 +/- 0.29 cm), height (5.5 +/- 0.09 m) and crown size (249 +/- 7.24 cm), while the CK had the lowest ones. The average biomass of new leaf (1-year-old), old leaf (2 or more-year-old), and branch per tree increased significantly (P<0.01) with enhancing tending treatments. The aboveground biomass of treatment FA was the biggest (44.0 t x hm(-2)), and that of CK was the smallest (14.9 t x hm(-2)). The leaf length and SLA at the early and terminal stages of development (May, June and September) had significant difference among the treatments, and the amount of community composition and the cover degree of undergrowth plants increased evidently under artificial tending treatments.

Biomass↗
PubMed2005

Rice from mercury contaminated areas in Guizhou Province induces c-jun expression in rat brain.

OBJECTIVE: Mercury (Hg), as one of the priority pollutants and also a hot topic of frontier environmental research in many countries, has been paid higher attention in the world since the middle of the last century. Guizhou Province (at N24 degrees 30'-29 degrees 13', E103 degrees 1'-109 degrees 30', 1 100 m above the sea level, with subtropical humid climate) in southwest China is an important mercury production center. It has been found that the mercury content in most media of aquatics, soil, atmosphere and in biomass of corns, plants and animals, is higher than the national standard. The present study aims to explore the influence of mercury pollution on the health of local citizens. METHODS: The effect of rice from two mercury polluted experimental plots of Guizhou Province on the expression of c-jun mRNA in rat brain and c-jun protein in cortex, hippocampus and ependyma was observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods. RESULTS: The results showed that the mercury polluted rice induced expression of c-jun mRNA and its protein significantly. Selenium can reduce Hg uptake, an antagonism between selenium and mercury on the expression of c-jun mRNA and c-jun protein. CONCLUSION: c-jun participates in the toxicity process of brain injury by mercury polluted rice, the expression of c-jun mRNA in brain, and c-jun protein in rat cortex and hippocampus can predict neurotoxicity of mercury polluted rice. People should be advised to be cautious in eating any kind of Hg-polluted foods. To reveal the relationship between c-jun induction and apoptosis, further examinations are required.

Animals↗
PubMed2005

[Antagonistic effects of selenium on the expression of c-fos in central nerval system of rat included by mercury contaminated rice].

The objective of this paper is to study the antagonisms between selenium and mercury and the effect of different species mercury on the brain injury. The expression of c-fos mRNA and c-FOS protein in rat brain induced by Hg-contaminated rice was observed by using reverse transcriptions polymerase chain reaction (RT-PCR) and immunocytochemical methods. The results show the Hg-contaminated rice induced significantly the expression of c-fos mRNA and c-FOS protein; selenium could antagonize mercury accumulative level in brain. Antagonistic effects of selenium on the expression of c-fos included by mercury and the molecule mechanism of the antagonisms between selenium and mercury was probed, too.

Animals↗
PubMed2005

[The effect of technological parameters of wide-band laser cladding on microstructure and sinterability of gradient bioceramics composite coating].

The gradient bioceramics coating was prepared on the surface of Ti-6Al-4V alloy by using wide-band laser cladding. And the effect of technological parameters of wide-band laser cladding on microstructure and sinterability of gradient bioceramics composite coating was studied. The experimental results indicated that in the circumstances of size of laser doze D and scanning velocity V being fixed, with the increasement of power P, the density of microstructure in bioceramics coating gradually degraded; with the increasement of power P, the pore rate of bioceramics gradually became high. While P = 2.3 KW, the bioceramics coating with dense structure and lower pore rate (5.11%) was obtained; while P = 2.9 KW, the bioceramics coating with disappointing density was formed and its pore rate was up to 21.32%. The microhardness of bioceramics coating demonstrated that while P = 2.3 KW, the largest value of microhardness of bioceramics coating was 1100 HV. Under the condition of our research work, the optimum technological parameters for preparing gradient bioceramics coating by wide-band laser cladding are: P = 2.3 KW, V = 145 mm/min, D = 16 mm x 2 mm.

Alloys↗
PubMed2005

[Toxicity effects of pentachlorophenol on Brachydanio rerio].

With embryo development technique, this paper determined the toxicity of pentachlorophenol (PCP) to Brachydanio rerio embryos. The results showed that the special effect duration of PCP on embryos was within 6 hours after embryos incubation. PCP could markedly inhibit the development of Brachydanio rerio embryos, and cause its malformation and even death. There were different toxicity endpoints which could be observed in embryos exposed to PCP with different time. The lethal effect sensitivity of embryos incubated after 48 hours was getting lower when the exposure time was getting shorter, the LC50 being the minimum (70.8 microg x L(-1)) for 0 hpf embryos, and the maximum (831.8 microg x L(-1)) for 24 hpf embryos. The acute toxicological endpoint of Brachydanio rerio embryos was in order of edema, no blood-circulation and heartbeat > incubation rate > stopping growth, and the most sensitive endpoints of Brachydanio rerio embryos to pentachlorophenol were no blood-circulation and half lethal concentration at 48 hrs.

Animals↗
PubMed2004

[Migration and differentiation of exogenous rat mesenchymal stem cells engrafted into normal and injured hearts of rats].

OBJECTIVE: To investigate the effects of different microcircumstances on the migration and differentiation of grafted rat mesenchymal stem cells (rMSC) in host myocardium and the feasibility of treatment of myocardial infarction by exogenous adult stem cells. METHODS: rMSC were isolated from the femurs and tibiae of a male Wistar rat and then purified, made into cell suspension, and labeled with DAPI. 35 female Wistar rat were divided randomly into four groups: acute myocardial infarction control group (AMI group, n = 10, the descending anterior branch of left coronary artery was ligated), acute myocardial infarction + rMSC transplantation group (AMI + rMSC group, n = 10, 1 - 3 hours after the ligation DAPI-labeled rMSC were injected into the peri-infarct tissues), normal heart + rMSC transplantation group (normal heart + MSC group, n = 10, DAPI-labeled rMSC were injected into the corresponding myocardium), and mono-nuclear cells transplantation group (AMI + MNCS, n = 5 DAPI-labeled mononuclear cells were injected into he periinfarct tissues). Ten weeks after the implantation, the rats were killed and their hearts were harvested. Immunohistochemistry was used to examine the troponin, GATA-4 and connexin-43. RESULTS: No lymphocyte proliferation and immonologic rejection were seen in the cardiac tissues of the rats implanted with rMSC. DAPI-labeled rMSC with blue nuclei were distributed extensively in the myocardium of the AMI + rMSC group, ovoid in shape and arranged in parallel with the cardiac muscle fibers, and were distributed sporadically like islands in the myocardium of the normal heart + rMSC group, irregular in shape and not arranged in parallel with the cardiac muscle fibers. No blue nucleus was seen in the cardiac tissues of the hearts implanted with DAPI-labeled mononuclear cells. Troponin and GATA4 were positive immunohistochemically in the implanted rMSC with blue nuclei and the host cardiac muscle cells of the AMI group and AMI + rMSC group, however, were negative in the implanted rMSC with blue nuclei and normal cardiac muscle cells of the normal heart + rMSC group. CONCLUSION: Purified rMSC are immunologically tolerable and can be used as donor cells for exogenous cells therapy. Capable of surviving and homing in both in normal and injured hearts, exogenous rMSC migrate and differentiate into cardiac muscle cell-like cells in myocardium with infarction, however, not in normal heart.

Animals↗