Biomedical subjects

C Wang

Publications and source records attributed to C Wang.

At least 217 records · Page 12Linked to original sources

PubMed2001

The relationship between health related quality of life and disease activity and damage in systemic lupus erythematosus.

OBJECTIVE: To evaluate the relationship between self-reported quality of life and disease activity, damage, impairment, disability, and handicap in systemic lupus erythematosus (SLE). METHODS: In this cross sectional study disease activity was measured with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the Systemic Lupus Activity Measure (SLAM), and damage by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index (SDI). Quality of life was assessed by the Medical Outcome Survey Short Form 36 (SF-36) and the EuroQol (EQ-5D). Multiple linear regression was used to identify significant associations of patients' health status, and logistic regression was used to evaluate the relationship of each of the 5 dimensions of the EQ-5D in terms of impairment, disability, and handicap. RESULTS: Damage was associated with the Physical Function (PF) and Social Function subscales of the SF-36. Disease activity was associated with the General Health (GH) subscale. Ability to carry out usual activities was strongly related to PF and GH as well as to global rating of the thermometer rating scale of the EQ-5D. Role Physical (RP) and Bodily Pain (BP) of the SF-36 were also associated with the EQ-5D rating scale. In addition, patients' ratings of anxiety and depression were strongly related to the Mental Health (MH) summary scale of the SF-36. CONCLUSION: Perceived health status of patients with lupus was associated with disease activity, damage, role physical, bodily pain, capacity for usual activity, and mobility. EQ-5D is a valid instrument for the measure of health related quality of life in SLE.

Adult↗

PubMed2001

Frequent inactivation of the TP53 gene in esophageal squamous cell carcinoma from a high-risk population in China.

Esophageal squamous cell carcinoma (ESCC) is one of the most common fatal cancers worldwide, and north central China has some of the highest rates in the world. Previous studies from tumors in this area of China have shown high frequencies of allelic loss on chromosome 17p13-11, which includes the region where the TP53 gene is found. We examined 56 ESCC patients using single-strand conformation polymorphism and DNA sequencing to assess the frequency and spectrum of TP53 mutation and the association between allelic loss at microsatellite marker TP53 and TP53 mutations. Ninety-six % of cases were found to have at least one genetic alteration, including TP53 mutation (77%), allelic loss within the TP53 gene (73%), and/or loss of heterozygosity at the TP53 microsatellite marker (80%); 75% had two or more such alterations, including 59% with both a point mutation and an intragenic allelic loss ("two hits"). The majority of mutations observed were in exon 5, where the most common type of nucleotide substitution was a G:C-->A:T or C:G-->T:A transition, including half that occurred at CpG sites. Allelic loss was most commonly found in exon 4 but was very common in exon 5 as well. Taken together, the multiple genetic alterations of TP53 in this population at high risk for ESCC indicate that there is a very high degree of genetic instability in these tumors, that TP53 is a primary target for inactivation, and that this tumor suppressor gene plays a critical role in the carcinogenesis process for ESCC.

Adult↗

PubMed2001

[Effect of tissue factor pathway inhibitor on the adhesion of platelet onto polyethylene and polyvinylchloride membranes].

Tissue factor pathway inhibitor(TFPI) is the major inhibitor of the extrinsic pathway of the blood coagulation cascade. Our previous study showed that TFPI could obviously prolong the blood coagulation time on the surface of polyethelene(PE) and polyvinylchloride(PVC) membranes in vitro and decrease the generation of thrombus on Dacron membrane in vivo. In the present study, the effect of TFPI on the adhesion of platelet onto PE and PVC membranes was investigated. PE or PVC membrane was cut into small pieces and incubated in 96-well culture plate with GST or GST-TFPI fusion protein at 4 degrees C over night. Freshly collected rabbit blood was mixed with 3.8% sodium citrate. Platelet-rich plasma was separated by centrifugation and then incubated with the treated membranes at 37 degrees C for 30 minutes. The membranes were then washed, fixed, and freeze-dehydrated Adhesion of platelet was observed through scanning electronic microscope. The result showed that GST-TFPI treatment significantly decreased the number of platelet adhered on the membrane when compared with the GST and control group, and it suggested that TFPI might have a great potential to be used as an anticoagulant for improving the hemocompatibility of biomaterials.

Animals↗

PubMed2001

Colon epithelial cell death in 2,4,6-trinitrobenzenesulfonic acid-induced colitis is associated with increased inducible nitric-oxide synthase expression and peroxynitrite production.

Peroxynitrite, derived from the reaction of nitric oxide (NO(.)) with superoxide (O(2)), is a potent nitrating and oxidizing agent that can induce apoptosis in a variety of different cell types. In the present study, we investigated the possible role of peroxynitrite as a mediator of colon epithelial cell death in rat colitis. Rat colon inflammation was induced by intracolonic administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) and rats were sacrificed 24 h after TNBS administration. Expression of inducible nitric-oxide synthase (iNOS) was detected by reverse transcription-polymerase chain reaction and immunohistochemistry. The enzymatic activities of Ca(2+)-independent iNOS and Ca(2+)-dependent constitutive nitric-oxide synthase were determined biochemically. Evidence of peroxynitrite-mediated cell injury was detected by immunostaining of nitrotyrosine. Apoptosis was examined by in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and DNA gel electrophoresis. To evaluate the specific contribution of peroxynitrite to the observed cell injury, a selective iNOS inhibitor, L-N(G)-[1-iminoethyl]lysine (L-NIL), was administered after TNBS induction. Morphological examination and analysis of TUNEL/cytokeratin double immunofluorescence revealed significant apoptosis in mucosal epithelial cells. Nitrotyrosine was colocalized with TUNEL, strongly demonstrating the association of peroxynitrite with the apoptotic death of colon epithelial cells. The administration of L-NIL reduced iNOS activity in 24-h lesions by 92% and also significantly attenuated both nitrotyrosine staining and apoptotic cell counts in the colon epithelium. These results strongly suggest that local elevated level of peroxynitrite produced from increased iNOS expression and activity is a major contributor to colon epithelial apoptosis during colon inflammation.

Animals↗

PubMed2001

Arthroscopic shoulder reconstruction: fast-track recovery and outpatient treatment.

Arthroscopic shoulder reconstructive surgery has been handled in many different ways. However, there currently is significant evidence and experience to show that doing this surgery on an outpatient basis is not only cost-effective and efficient, but safe and beneficial to patients. New arthroscopic surgical techniques and the use of regional interscalene anesthesia have been shown to provide effective and comfortable intraoperative conditions, while allowing for prolonged analgesia and quicker recovery with minimal side effects. The authors will discuss their approach to surgery, anesthesia, and recovery for outpatient shoulder reconstruction.

Ambulatory Surgical Procedures↗

PubMed2001

[EROD induction in liver microsome of carp(Cyprinus carpio) by nitroaromatic hydrocarbons in vitro].

Nine nitroaromatic hydrocarbons (NAHs) induction of EROD activity was investigated by an in vitro assay based on carp (Cyprinus carpio) hepatic microsome system. All nine NAHs tested were found to induce the activity of EROD. There was dose-effect relationship between EROD activity and concentrations of NAHs. It was found that EROD activity was different, when different groups substituted at the same position of benzene ring, or the same group was at different position of benzene ring.

Animals↗

PubMed2001

Genotyping and preparation of the recombinant nucleocapsid protein antigen of hantavirus.

OBJECTIVE: To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrome (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length polymorphism (RT-PCR-RFLP) for genotyping of hantavirus. METHODS: One group of primers was used to clone the full-length S genome segment and the partial S genome segment of the N-terminal. The two cloned genes were both fusionally expressed and non-fusionally expressed in the T7 system. The other group of primers was used to establish a RT-PCR method to detect RNAs in 37 virus isolates, 2 positive standard virus strains of hantavirus and 5 negative controls. The method for typing RFLP was set up by digesting the PCR products of 20 virus isolates with Ras I and Hind III. RESULTS: The non-fusionally expressed products with a working concentration of 1:10,000 by chapping enzyme-linked immunosorbent assay (cELISA), presented good biological activity though yields were lower than that of the fusionally expressed products. The specific component of the hantavirus genome (299 bp or 577 bp) was seen in all viral samples. The genotyping of hantavirus showed that 9 out of the total were Hantann (HTN) viruses, 8 were seoul (SEO) viruses and 3 were not determined. CONCLUSIONS: The good working titrer of expressed recombinant antigen showed that it has the potential to replace the natural antigen for detecting hantavirus antibodies. On comparison with cELISA, the detection rates for these two methods were 100% and 84.6%, and the coincidence rate was 84.6%. The former had a 15.4% higher sensitivity than the latter. The typing efficiency of RT-PCR-RFLP and sero-typing method was 85% (17/20) and 55% (11/20), respectively, showing that the former was 30% higher than the latter, while their results were highly consistent.

Antibodies, Viral↗

PubMed2001

Determination of photonic efficiency and quantum yield of formaldehyde formation in the presence of various TiO2 photocatalysts.

Illumination of aqueous TiO2 suspentions yields hydroxyl radicals, which can be trapped by methanol producing formaldehyde (HCHO). In this work, the photonic efficiency and quantum yield of HCHO formation in colloidal TiO2 solutions and, P25 and UV 100 suspensions have been determined. Differences in photocatalytic activity of the three photocatalysts have been found and are discussed. The photonic efficiency of HCHO formation in the presence of P25 and UV 100 depends on the concentration of TiO2 and the pH. The critical concentration is 2.5 g/L. Below this, the photonic efficiency with P25 is higher than with UV 100, and vice versa. Optimum pH values for P25 and UV 100 giving the maximum photonic efficiency are 7.7 and 10.4, respectively. Compared to P25 and UV 100, the true quantum yield of HCHO formation in colloidal TiO2 solution varies a little with pH and virtually does not change with the amount of loading of TiO2. The true quantum yield varies as the inverse square root of light intensity. The quantum yield increases from 0.02 to 0.08 when the absorbed photon flux decreases from 8.1 x 10(-7) Ein/L s to 4.9 x 10(-8) Ein/L s. A simple model is presented to explain the experimental observation.

Catalysis↗

PubMed2001

A novel phospholipase D of Arabidopsis that is activated by oleic acid and associated with the plasma membrane.

Oleate-dependent phospholipase D (PLD; EC 3.1.4.4) has been reported in animal systems, but its molecular nature is unkown. Multiple PLDs have been characterized in plants, but none of the previously cloned PLDs exhibits the oleate-activated activity. Here, we describe the biochemical and molecular identification and characterization of an oleate-activated PLD in Arabidopsis. This PLD, designated PLDdelta, was associated tightly with the plasma membrane, and its level of expression was higher in old leaves, stems, flowers, and roots than in young leaves and siliques. A cDNA encoding the oleate-activated PLD was identified, and catalytically active PLDdelta was expressed from its cDNA in Escherichia coli. PLDdelta was activated by free oleic acid in a dose-dependent manner, with the optimal concentration being 0.5 mM. Other unsaturated fatty acids, linoleic and linolenic acids, were less effective than oleic acid, whereas the saturated fatty acids, stearic and palmitic acids, were totally ineffective. Phosphatidylinositol 4,5-bisphosphate stimulated PLDdelta to a lesser extent than oleate. Mutation at arginine (Arg)-611 led to a differential loss of the phosphatidylinositol 4,5-bisphosphate-stimulated activity of PLDdelta, indicating that separate sites mediate the oleate regulation of PLDdelta. Oleate stimulated PLDdelta's binding to phosphatidylcholine. Mutation at Arg-399 resulted in a decrease in oleate binding by PLDdelta and a loss of PLDdelta activity. However, this mutation bound similar levels of phosphatidylcholine as wild type, suggesting that Arg-399 is not required for PC binding. These results provide the molecular information on oleate-activated PLD and also suggest a mechanism for the oleate stimulation of this enzyme.

Amino Acid Sequence↗

PubMed2001

[Studies of the determination of glycyrrhizin acid kali salt by HPLC and the pharmacokinetics].

To find a practive and quick method determining GK concentration in blood by HPLC and to study its pharmacokinetics. GK from Glycyrrhiza uralensis Fisch was extracted and purified. GK were administered to mice by i.v. and ig. The Concentration of GK in blood at expected time was determined by HPLC. The data was dealed with by 3 P 87 programe. The concentration-time curve of i.v. 0.1% GK 40 mg/kg is in accordance with tow-compartment model. t1/2 alpha = 5.128 min, t1/2 beta = 51.196 min, AUC = 7477.642 (micrograms/ml).min, Cl(s) = 0.0956 microgram/min(microgram/ml). The c-t curve of ig. 2.2% GK 500 mg/kg is in accordance with tow compartment model, t1/2 alpha = 15.97 min, t1/2 beta = 200.05 min, AUC = 2453.96(micrograms/ml).min, Cl(s) = 3.642 micrograms/min(micrograms/ml). HPLC is a quick and practive method to determin the concentration of GK in blood.

Animals↗

PubMed2001

[Changes in respiratory and circulatory function during sequential invasive-noninvasive mechanical ventilation].

OBJECTIVE: To investigate the change of respiratory and circulatory function in COPD during sequential invasive-noninvasive mechanical ventilation. METHODS: 12 COPD patients with type II respiratory failure were ventilated via endotracheal intubation. When pulmonary infection was under control (the appearance of "PIC Window"), all patients were extubated and received mask ventilation. The parameters of hemodynamics oxygenation and esophageal pressure were measured during endotracheal ventilation and mask ventilation (3 hrs after extubation). RESULTS: The change of respiratory and circulatory parameters were not significantly different between invasive mechanical ventilation and noninvasive mechanical ventilation (P > 0.05). CONCLUSION: The respiratory and circulatory function of COPD patients remained stable during sequential invasive-noninvasive mechanical ventilation.

Adult↗

PubMed2001

[The influence of dexamethasone on mRNA expression of interleukin-5, interleukin-3 and granulocyte-macrophage colony-stimulating factor receptors in eosinophils of guinea pig asthma model].

OBJECTIVE: To investigate the iufluence of dexamethasone (DM) on expression of interleukin-5 receptor alpha(IL-5R alpha), interleukin-3 receptor alpha (IL-3R alpha), granulocyte-macrophage-colony-stimulating factor receptor alpha(GM-CSFR alpha) and common beta receptor (beta cR) in bronchalveolar lavage fluid (BALF) eosinophils in guinea pig asthma model, and to study the mechanism of promotion effect of steroid on eosinophil apoptosis. METHODS: 18 guinea pigs were divided into three groups randomly, normal control group, asthma group and DM-treated group. Asthma models of guinea pig were sensitized by ovalbumin(OVA). Hypodense EOS (HEOS) and normodense EOS (NEOS) were purified from BALF by gradients of percoll. Apoptosis was detected by method of TdT-mediated dUTP nick end labeling. The mRNA expression of IL-5R alpha, IL-3R alpha, GM-CSFR alpha and common beta receptor (beta cR) in eosinophils were measured by RT-PCR and in situ hybridization. RESULTS: Apoptosis of HEOS and NEOS in asthma group(4.0 +/- 2.0 and 3.0 +/- 2.0, respectively) were significanteylower than normal group(8.0 +/- 2.0 and, 7.0 +/- 2.0 respectively, P < 0.01), while the numbers of EOS cells (75.2 +/- 12.6 and 50.7 +/- 11.2, respectively) were significantly higher than normal group (4.8 +/- 1.5 and 9.5 +/- 2.6, respectively, P < 0.01). The BALF HEOS and NEOS of asthma group were remarkably reduced after DM treatment (14.8 +/- 8.0 and 20.0 +/- 7.0, respectively, P < 0.01), Eosinophils apoptosis in DM-treated group (24.0 +/- 5.0 and 22.0 +/- 4.0, respectively) was remarkably higher than those in asthma group (P < 0.01); The expressions of IL-5R alpha, IL-3R alpha, GM-CSFR alpha mRNA of BALF EOS of asthma group were significantly lower, but the expression of beta cR mRNA was significantly higher than those of normal group(P < 0.01, 0.05). The expressions of IL-5R alpha, IL-3R alpha, GM-CSFR alpha mRNA in EOS of DM-treated group were significantly higher, while the expression of beta cR mRNA were significantly lower than those of asthma group (P < 0.01, 0.05). CONCLUSIONS: DM promote the apoptosis of BALF EOS of guinea pigs asthma models. and reduce EOS infiltration in lung of guinea pigs asthma models. It also decreased the effect of IL-5, IL-3 and GM-CSF and promoted the apoptosis of lung EOS through inducing the mRNA expression of their specific alpha chain and reducing the mRNA expression of the common beta chain.

Animals↗

PubMed2001

[Characteristics and distribution pattern of farmland patch in river valley in middle and low Taihang mountain area--a case study in Yanzhi River in Fuping County, Hebei Province].

Based on the investigations in the main valley of Yanzhi river in Fuping county of Hebei Province, the characteristics and distribution patterns were analyzed. The results indicated that farmland patches were distributed in the whole valley, except the headstream reach. With the increase of human disturbances, the proportion of farmlands increased along the river from upstream to downstream, while in natural landscapes, the environmental heterogeneity and fragmentation of farmlands decreased. The area of Yanzhi river valley totaled 2297.09 hm2, mainly composed by farmland. There were 117 farmland patches mainly distributed along the riverbank in the valley, totalling 1027.78 hm2 and occupying 44.74% of the valley, which were very well irrigated, but always endangered by flood. The farmland patches were not symmetrically distributed along river, with 57.17% of farmland located on the left side of bank. The width of farmland patch presented an increasing trend, with a remarkable variation. The farmland patches were mainly strip-shape.

Agriculture↗

PubMed2001

[Effect of rare earth elements on the seedling ratio of crops].

The effects of rare earth elements(REEs) on the relative seedling ratio of three crops(rice, rape and soybean) in three soil(red soil, yellow fluvo-aquic soil and yellow cinnamon soil) were studied according to OECD method, and the LC50 were obtained. Toxicity effect of REEs on rice was minimum among the crops tested. The toxicity on crops in yellow cinnamon soil was lower, whereas on soybean in yellow fluvo-aquic soil and on rape in red earth were higher.

Crops, Agricultural↗

PubMed2001

[The accuracy analysis on Kriging estimation of the water quality parameters of lakes].

The spatial distribution of pollutants in lakes is required in the study of lakes. The key issue is the spatial optimal estimation. This paper elaborated the characteristics of Kriging variance and analyzed systematically the accuracy of Kriging estimation on water quality parameters of lakes in the light of a practical example of Taihu Lake. The accuracy of estimation was determined by many factors such as variogram, distribution of sampling sites and so on, and was not related to the values of sampling data.

Fresh Water↗

PubMed2001

[Inhibition effects of octreotide on the growth of hepatocellular carcinoma in vitro and in vivo].

OBJECTIVE: To investigate the effects of somatostatin analogue octreotide on the proliferation and apoptosis of human hepatocellular carcinoma (HCC) cell line as well as the growth of HCC xenografts in nude mice. METHODS: The effects of octreotide on the proliferation and apoptosis of SMMC-7721 HCC cells was measured by 3H-thymidine incorporation into DNA and the TdT-mediated dUTP nick end labeling assay (TUNEL) or flow cytometric assay separately. Nude mice bearing xenografts of the cell line were treated with octreotide or saline as a control daily until eight weeks after tumor implantation. RESULTS: Incubation with octreotide decreased 3H-thymidine incorporation into DNA of SMMC-7721 cells by approximately 50% at a concentration of 1 mumol/L. The inhibit effect of octreotide showed a concentration dependence. After 96 h incubation, total cell count was decreased 52.2% compared with control. When cells were treated by octreotide at 1 x 10(-6) mol/L for 24 hours, the apoptosis rates was (15.2 +/- 2.4)%. At necropsy, in mice given octreotide, the mean tumor weight were significantly lower than that of control group (0.27 +/- 0.05 vs 0.85 +/- 0.37, P < 0.01). The inhibition rate of tumor in vivo at 2 months was 68.2%. CONCLUSION: Octreotide is effective in inhibiting growth of HCC both in vivo and in vitro significantly. The mechanisms of antineoplastic effect action may involved in inhibiting DNA synthesize and inducing apoptosis of tumor cells.

Animals↗

PubMed2001

[Changes of plasma p-selectin and nitric oxide in patients with pregnancy induced hypertension].

OBJECTIVE: To study the roles of P-selectin and nitric oxide (NO) on the etiology of pregnancy induced hypertension (PIH). METHODS: The levels of plasma P-selectin and nitrite and nitrate (NO2-/NO3-) were determined in 36 patients with PIH. The data were compared with those of normal pregnant group (n = 18) and healthy non-pregnant group (n = 19). The levels of plasma P-selectin were measured by means of enzyme-linked immunosorbent assay (ELISA) and levels of plasma NO2-/NO3- were measured by Griess reaction after the nitrate was reduced by a Cadmium-reduction method. RESULTS: The result showed: (1) The level of P-selectin in the normal pregnant group (48.92 +/- 15.16) micrograms/L was higher than that in non-pregnant group [(30.16 +/- 8.42) micrograms/L, P < 0.001]. There was no significantly statistical difference in the levels of P-selectin between the normal pregnant group and the mild PIH group (P > 0.05). The levels of P-selectin in the moderate and severe PIH group (70.11 +/- 17.65) micrograms/L were higher than those in the mild PIH group [(47.33 +/- 17.95) micrograms/L, P < 0.01] and the normal pregnant group (P < 0.001). (2) The concentration of NO2-/NO3- in normal pregnant group was higher than that in non-pregnant group (P < 0.01). The concentration of NO2-/NO3- in PIH group were lower than was in normal pregnant group (P < 0.001). The NO2-/NO3- in mild group was lower than that in normal pregnant group (P < 0.001). The Plasma concentration of NO2-/NO3- in moderate and severe PIH group was lower than that of mild group (P < 0.05). (3) There was a negative correlation between the plasma concentration of P-selectin and NO2-/NO3- in the PIH group. CONCLUSION: The changes of plasma levels of P-selectin and NO are related to the occurrence and development of PIH.

Adult↗

PubMed2001

Effects of extrinsic positive end-expiratory pressure on work of breathing in patients with chronic obstructive pulmonary disease.

OBJECTIVE: To investigate the effects of extrinsic positive end-expiratory pressure (PEEPe) on work of breathing in patients with chronic obstructive pulmonary disease (COPD) and their corresponding mechanism. METHODS: Ten ventilated patients with COPD were included in the study. A Bicore CP-100 pulmonary monitor (Bicore Monitoring System, USA) was used for monitoring respiratory mechanics. First, dynamic intrinsic positive end-expiratory pressure (PEEPi, dyn) was measured when PEEPe was zero, which was called PEEPi, dynz. Then the PEEPe was set randomly at 0%, 40%, 60%, 80% and 100% of PEEPi, dynz respectively. Pulmonary mechanics and other parameters (heart rate, blood pressure and blood gas analysis) were measured 30 minutes after the level of PEEPe was changed. RESULTS: Work of breathing patient (WOBp), pressure time product, difference of esophageal pressure and PEEPi, dyn decreased significantly when PEEPe was applied, and continued decreasing as PEEPe was increased. Work of breathing ventilator increased significantly when PEEPe was increased to 80% and 100% of PEEPi, dynz. Significantly positive linear correlation was found between the changes in WOBp and in PEEPi, dyn. CONCLUSIONS: WOBp decreases gradually as PEEPe is increased. WOBp decreases by narrowing the difference between the alveolus pressure and the central airway pressure at the end of expiration when PEEPe is applied.

Aged↗