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Biomedical subjects

C Zhang

Publications and source records attributed to C Zhang.

At least 451 records · Page 25Linked to original sources
PubMed1998

[Determination of formaldehyde in indoor air by gas chromatography].

Formaldehyde in indoor air was collected by water, derivatized with 2,4-dinitrophenylhydrazine and extracted by cyclohexane. The sample was separated on an OV-17 and QF-1 mixed chromatographic column and determined by electron capture detector. The detection limit was 0.02 mg/L (solution), the minimum detectable concentration was 0.01 mg/m3 while 10 L indoor air was collected. The results show that this is a rapid and sensitive method with less interferences and fairly good precision. The recoveries were 71.0%-90.4% and coefficients of variation were 4.1%-6.5%. The development of this method has made a reliable methodological foundation for the determination of formaldehyde in indoor air.

Air Pollutants↗
PubMed1998

[Observation on effect of shenmai injection in treating patients of congestive heart failure].

OBJECTIVE: To observe the clinical therapeutic effect of Shenmai Injection (SMI) in treating patients of congestive heart failure. METHODS: Effect of 16 cases treated with SMI or potassium magnesium aspartate was observed by randomized crossover method and compared. RESULTS: By using SMI for 2 weeks, patients' left ventricular ejective fraction (LVEF) could be increased from 29.5 +/- 9.0 to 36.6 +/- 10.2 (P < 0.05), the heart function of 68.75% patients was improved, no side effects or toxicity was observed. Potassium magnesium asparate could improve heart function in 37.50% patients only but with no effect on LVEF. CONCLUSION: SMI is an effective and safe therapy in treating patients with congestive heart failure.

Adult↗
PubMed1998

[Isolation, purification and determination of the constituents of a toxic protein from plant amenone].

A toxic protein constituent named AME from the stems of plant amenone, have been isolated and purified. Through CM-SFF column chromatography and gel filtration on Sephacryl S-200 column with phosphate saline buffer as mobile phase. All of the operations were performed at 4 degrees C. The pulverized plant amenone material was soaked in phosphate saline buffer, homogenized, left standing overnight and then squeezed through coarse cloth by wringing. The supernatant was applied on the S-SFF column. Then, the column was eluted with the phosphate buffer containing 1 mol/L NaCl. The eluate was collected and dialyzed against water and phosphate buffer. The chromatography of the crude toxin dialyzed was carried out on the CM-SFF column with gradient elution of phosphate buffer containing NaCl. The fourth peak was collected and then applied on a gel filtration Sephacryl S-200 column using neutral phosphate buffer as mobile phase. The protein was further separated on two connected Protein 125 columns with mobile phase of 0.2 mol/L phosphate buffer (pH 6.5), the eluate was monitored at 280 nm on photodiode array detector. The protein presents typical the absorption spectrum of protein in ultraviolet region with the strong absorption at 280 nm and the weak absorption at 260 nm. The purity of peak of the protein was judged from the spectrum. The molecular weight of AME measured by two connected protein columns was approximately 35,000 D. The composition of amino acids was determined with OPA post-column derivatization/fluorescence detection.

Amino Acids↗
PubMed1998

Influence of space conditions on photosynthetic pigment contents and chloroplast ultrastructure of maize leaves.

Dried seeds of maize inbred lines were carried by recoverable satellite to space conditions at an altitude of 175-253 km from sea level for 15 d. The effects of space flight on ultrastructure and photosynthetic pigment contents of maize leaves were studied. Various changes in structure were observed. Chloroplast envelope membrane notch, swelling of thylakoids, less granum stacks and stroma thylakoid membranes, and changes of chloroplast contour were often seen. The contents of chlorophyll a, chlorophyll b, and chlorophyll a+b and carotenoids tended to be lower, but Ca/Cb ratio tended to be higher in the leaves from space flight maize in comparison with ground control.

Chlorophyll↗
PubMed1998

[Determination of adenosine and 3'-deoxyadenosine in Cordyceps militaris (L.) Link. by HPLC].

The establishment of a quantitative determination method by HPLC for adenosine and 3'-deoxyadenosine in Cordyceps militaris is reported. The sample was extracted with water under ultrasonic management for 2 hours. Chromatographic conditions: YWG C18 10 microns 5 mm x 200 mm; mobile phase consisted of NaH2PO4-NaOH buffer solution (pH 6.8); UV detection at 260 nm. The recoveries of adenosine and 3'-deoxyadenosine were 95.8% +/- 0.64% and 100.6% +/- 0.65% (n = 5) respectively.

Adenosine↗
PubMed1998

[Radioimmunoimaging of bladder tumor with the intravesical administration of technetium -99m labelled monoclonal antibody].

OBJECTIVE: To make radioimmunoimaging of bladder tumor simple, safe and reliable. METHODS: Anti-human bladder carcinoma cell line BIU-87 monoclonal antibody-BDI-1 was labelled with technetium -99m by direct mercaptoethanol reducing method. RESULTS: The labelling rate was 69.6% and the radiochemistry pruity was higher than 95%. 33 patients received radioimmunoimaging of bladder tumor with the intravesical administration of technetium -99m labelled monoclonal antibody. The false positive rate was zero. 88.5% of all 29 bladder cancer patients had got positive immunoscintigraphy results, and 65.2% of them were confirmed by cystoscopic results. Both primary and recurrent tumor could be detected clearly and the smallest tumor detected was 0.5 cm in diameter. There were some differences between the radioimmunoimaging and cystoscopic results in 7 of 11 multitumor cases, which included tumor size, number and location. CONCLUSION: It is required to use more suitable isotopes and/or monoclonal antibodies to increase its sensitivity.

Administration, Intravesical↗
PubMed1998

[Therapeutic arterial embolization of oral and maxillofacial plexiform hemangioma with absolute ethanol and gelfoam particles].

OBJECTIVE: To treat arteriovenous malformations of the oral and maxillofacial region by embolization with absolute ethanol and Gelfoam particles. METHODS: Six patients with arteriovenous malformations of the oral and maxillofacial region were treated by selective embolization through the feeding arteries with absolute ethanol and Gelfoam particles. RESULTS: A follow up at 2-13.5 months after embolization showed no recurrence. Response rate is 100 percent. CONCLUSION: Alcohol and Gelfoam as an agent used to ablate high-flow vascular malformations in oral and maxillofacial region is a method of choice.

Adolescent↗
PubMed1998

[Long-term outcome of selective posterior rhizotomy for spastic cerebral palsy].

OBJECTIVE: To investigate the long term outcome and complication of selective posterior rhizotomy for spastic cerebral palsy. METHOD: 26 patients with cerebral palsy who had received SPR were followed up for four years. RESULT: In the 9 patients who could walk and stand up from squatting position independently, 7 could stand steadily on one foot after operation. In the 12 who patients could walk and stand up from squatting position dependently, 7 could walk independently in the room after operation. In 5 patients couldn't walk and stand up from squatting position, 3 patients could walk dependently in the room after operation. Complications occurred in 3 patients. CONCLUSION: Selective posterior rhizotomy is effective in the treatment of spastic cerebral palsy. Strictly selecting candidates for the operation and good rehabilitation training before and after operation should be emphasized for good results.

Cerebral Palsy↗
PubMed1998

[Host-guest molecule interaction mechanism of hemostatics with liposomes and red blood cells studied with fluorescence polarimetric method].

The supermolecule compounds of adrenobazone, p-aminomethylbenzoic acid, vitamin K1, 6-amino caproic acid with liposomes and red blood cells were studied by fluorescence polarimetric method. The mechanisms of formation of the supermolecule compounds were examined by fluorescence probe of the link of 1,6-dipheny-1,3,5-hexatriene (DPH) with liposomes which were taken as a model of blood cells. The interaction mechanism of hemostatics with red blood cells was described according the quantitative relationship between polarization value (P) and the microviscosity [formula: see text]. The result showed that the acting force between hemostatics and liposomes or that between hemostatics and red blood cells were mainly supermolecular acting force. The acting force between vitamin K1 and cytomembrane is hydrophobic force and those between adrenobazone, p-aminomethylbenzoic acid, or 6-amino caproic acid and cytomembrane are hydrogen bond or electrostatic force. Under the same drug concentration, all of the four haemostatics can reduce the fluidity of the cell membrane, which benefits blood coagulation. The binding ways of hemostatics with red blood cells was also discussed.

4-Aminobenzoic Acid↗
PubMed1998

[Longitudinal surveillance of sensitivity of Plasmodium falciparum to pyronaridine in south Yunnan].

AIM: To understand the changes in the sensitivity of Plasmodium falciparum to pyronaridine in the south of Yunnan Province. METHODS: WHO standard in vivo and in vitro microtest was used. RESULTS: In 1984-1985 and 1995, 36 and 39 cases of acute falciparum malaria were observed, the average defervescence time being 32.7 +/- 16.0 h and 56.2 +/- 27.4 h, the mean asexual parasite clearance time, 64.2 +/- 22.9 h and 55.3 +/- 11.8 h, and the recrudescence rate of patients followed up for 28 days, 15.2%(5/33) and 37.5%(9/24), respectively. The resistance rates of resistant isolates by in vitro microtest were 0(0/24), 8.8%(3/34), 13.8%(4/29) and 36.4%(4/11) in 1988, 1990, 1992 and 1995, respectively, while the corresponding ID50 were 13.0, 20.0, 32.0 and 40.0 nmol/L, ID95 were 48.0, 136.0, 325.0 and 330.0 nmol/L, the mean concentrations for complete inhibition of schizont formation were 32.6, 99.5, 148.2 and 190.1 nmol/L, respectively. CONCLUSION: The sensitivity of Plasmodium falciparum to pyronaridine was found to have a tendency of continuous dropping in south Yunnan.

Adolescent↗
PubMed1998

[The relationship between expression of oncogene proteins and HBeAg in chronic hepatitis B virus infection].

To study the relationship between abnormal expression of oncogene protein and HBV replication, we detected the expression of protein products C-erbB-2 P185, ras P21 and tumorsuppressor gene product P53 and HBeAg in the serum of 64 patients with chronic HBV infection by using immunohistochemical technique and ELISA. The results were as follows. The positive detection rates of serum HBeAg in C-erbB-2 P185 and ras P21 oncogenes positive groups were 89.4% and 84.6% respectively, but only 20% and 48% in C-erbB-2 P185 and ras P21 negative groups. It suggested that there is a close correlation between the over-expression of C-erbB-2 P185, ras P21 and replication of HBV.

Adolescent↗
PubMed1998

[Integrating qualitative analysis with quantitative grey relation analysis in the comprehensive evaluation for solving medical problems].

This paper integrates qualitativ analysis with quantitative grey relation analysis in the comprehensive evaluation for solving medical problems, especially diagnostic problems, and good results are obtained. In it, some new medical concepts such as diagnostic value, diagnostic grey degree and information cover rate are defined. The given example demonstrates that when used in clinical diagnosis, this diagnostic model makes a feature of high diagnostic coincidence rate as well as low misdiagnosis rate and it overcomes the common disability of general medical diagnostic model in quantitative analysis.

Clinical Competence↗
PubMed1998

[The investigation of interaction for silver(I) ion with gamma-globulin by resonance spectroscopy].

The interaction for silver (I) ion with gamma-globulin has been investigated by resonance spectroscopy. It is shown that 2 or 4 coordination species for amino acid residues of gamma-globulin with Ag (I) ion were formed and their resonance spectra appear to be different in amide bands region. It has been studied that effect of reaction time on resonance Raman(RR) spectra in heat condition. Results showed that the intensity of RR has maximum at about 15 min of reaction, and after the time, Ag (I) ion on species will reduced to elemental silver.

Protein Binding↗
PubMed1997

Development of a new kind of dual modulated QCM biosensor.

To distinguish the mass loading effect from the total frequency change is a problem in the application of a quartz crystal microbalance (QCM) biosensor in the liquid phase. Based on the characteristic damping theory, this paper proposes a new method of dual modulation to solve this problem. Using polyethyleneimine to immobilize anti-SE (staphylococcin enterotoxin) antibody (C2 type), a dual modulated QCM SE biosensor was developed and the experiment proved that it has little cross-reaction with B-type SE. The measuring curve of the sensor was also determined through experiment.

Biosensing Techniques↗
PubMed1997

Monitoring early cellular responses in apoptosis is aided by the mitochondrial membrane protein-specific monoclonal antibody APO2.7.

A recently described mitochondrial membrane protein-specific monoclonal antibody, APO2.7, was examined for monitoring early apoptotic responses in anti-CD95 (7C11)-induced Jurkat cells. Jurkat cells were harvested at 1.5, 3, 4.5, 6, 12, and 18 h after induction of apoptosis, and APO2.7 antibody monitored in unprocessed (no permeabilization agent used prior to staining) and processed (permeabilized prior to staining) cells. Light-scatter changes (decreased forward-scatter and increased side-scatter) by flow cytometry were observed after 3 h, and detection of cell permeability in unprocessed cells, as measured by light microscopic examination of Trypan blue-stained cells and flow cytometric detection of tubulin, showed little change until after 6 h. In addition, unprocessed cells stained with APO2.7 antibody showed little increase in staining until after 6 h following induction of apoptosis, when DNA fragmentation was demonstrated by flow cytometry and gel electrophoresis; however, processed cells stained with APO2.7 antibody showed significant increase in staining after 1.5 h. Detection, using annexin V and flow cytometry, of phospholipid membrane asymmetry from exposure of phosphatidylserine showed greater, apparent nonspecific staining in noninduced cells as compared to the other markers of apoptosis, but nearly paralleled the results of APO2.7 staining in processed cells from 3-18 h following CD95 induction of apoptosis. The data presented herein indicate that the mitochondrial membrane protein-specific antibody, APO2.7, is useful as a marker for the detection of apoptotic cells.

Annexin A5↗
PubMed1997

Activation of the megakaryocyte-specific gene platelet basic protein (PBP) by the Ets family factor PU.1.

Platelet basic protein (PBP) is a chemokine family member that is only found in platelets and their precursors megakaryocytes. The PBP gene is physically linked to the gene for another platelet-specific chemokine, platelet factor 4. While the biological basis of platelet factor 4 expression has been pursued by others, the regulatory features controlling the platelet-specific expression of PBP have not been investigated. In this article, we examined the molecular basis by which this megakaryocyte-specific gene is regulated. Transient expression studies of truncated reporter constructs containing from 4.5 to 0.1 kilobases of the functional PBP gene 5'-flanking region, demonstrated that the proximal 0.1 kilobases of the promoter was sufficient for high levels of expression in human erythroleukemia and CHRF-288 cells, two megakaryocytic cell lines. However, none of these constructs was expressed above background levels in HeLa and 293 cells, two non-megakaryocytic cell lines. Further truncation of this promoter suggested that there was an important regulatory element(s) within a pyrimidine-rich tract. Mobility shift analysis of the pyrimidine-rich tract defined a region between -85 and -64 which bound to a nuclear factor(s). This region contains sequences matching the consensus Ets-binding site from -78 to -75 base pairs. In particular, we noted that this site matched a PU.1 consensus sequence known as a PU box. Mobility shift and supershift studies with nuclear extracts as well as recombinant PU.1 protein and anti-PU.1 antibody further confirmed that PU.1 was the specific Ets family factor that bound to this site. Transient expression assays using reporter constructs which contained point mutations that abrogated PU.1 binding also significantly reduced PBP promoter activity in human erythroleukemia and CHRF cells. In addition, while all reporter gene constructs containing PBP promoters were completely inactive in HeLa cells, transactivation experiments using a PU.1 expression construct demonstrated that exogenous expression of PU.1 could increase reporter gene expression up to 8-fold in these cells. Finally, the role of PU.1 in PBP gene expression was compared between wild-type and PU.1-null embryonic stem (ES) cells that were differentiated in vitro into cells that resembled megakaryocytes both morphologically and immunologically. We found that PBP gene expression in the differentiated PU.1(-/-) null ES cells (as determined by semi-quantitative reverse transcriptase-polymerase chain reaction) was more than four times lower than that in the wild-type ES cells, while other platelet-specific genes were expressed equally or similarly in the two ES cell lines. Previous reports have shown that PU.1 is expressed in several hematopoietic lineages, including megakaryocytes. However, the functional role of PU.1 has only been previously demonstrated in the myeloid and lymphoid lineages. Therefore, our studies are the first to show the biological importance of this nuclear factor in the regulated expression of a megakaryocyte-specific gene.

Binding Sites↗
PubMed1997

Involvement of endogenous opioids and ATP-sensitive potassium channels in the mediation of carbachol-induced antinociception at the spinal level: a behavioral study in rats.

The effects of intrathecally administered (i.t.) atropine, glibenclamide, a blocker of ATP-sensitive potassium channels, or naloxone on the antinociception produced by i.t. carbachol or morphine were observed in rats by tail-flick (TF) test. The results showed that: (1) i.t. carbachol produced a dose-dependent antinociception and it could be antagonized by i.t. atropine; (2) the antinociception produced by i.t. carbachol could be blocked dose-dependently by i.t. glibenclamide or i.t. naloxone; (3) the antinociception produced by i.t. morphine could be blocked dose-dependently by i.t. glibenclamide, but not by i.t. atropine. The results suggest that the antinociception produced by activation of muscarinic receptors at the spinal level might be mediated by endogenous opioids and ATP-sensitive potassium channels in a cascade form.

Adenosine Triphosphate↗