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C Zhang

Publications and source records attributed to C Zhang.

At least 163 records · Page 9Linked to original sources
PubMed2001

Involvement of pressure-related mechanism in activation of inducible nitric oxide synthase.

The goal of this study was to clarify the relationship between blood pressure and inducible nitric oxide synthase (iNOS) activity. Different levels of blood pressure were obtained by long-term (six days) intravenous infusion of different concentrations (0.3%-8%) of NaCl solution to normal SD rats. iNOS activity assay and measurement of urinary nitrate/nitrite (UNOx), an index of NO production of the whole body, were carried out by isotope-labeled L-arginine conversion rate measurement and Greiss Reaction respectively. Groups of normotensive and hypertensive rats including normal Wistar rats, normal Sprague-Dawley (SD) rats, high NaCl-induced hypertensive rats (NaHR) and spontaneously hypertensive rats (SHR) were used to detect the changes in iNOS protein under normotension and hypertension by Western blotting. iNOS activity of aorta and kidney tissues and UNOx increased more significantly in hypertensive animals than in the normotensive control ones. Accordingly, iNOS protein in the aortas of NaHR and SHR increased by 149% and 261% respectively. It is suggested that in addition to cytokine and bacterial products etc, blood pressure is also an effective regulatory factor involved in iNOS activation and expression.

Animals↗
PubMed2001

[A simple and rapid new method for SNP typing by single-tube bi-directional allele specific amplification].

OBJECTIVE: To establish a new method for single nucleotide polymorphism(SNP) typing based on allele specific PCR: single-tube bi-directional amplification (SB-ASA), and study the influence on specific extension by introducing a mismatch at the third 3'terminal base of allele specific primers. METHODS: Two allele specific primers, with a mismatch introduced at the third 3'terminal base, were both included in PCR system; they extended in opposite directions and amplified two allele specific fragments different in size. The genotype was determined by observing the length of amplified fragments after agarose electrophoresis. The proper ranges of annealing temperature (Ta) under which primers can specifically extend were achieved by observing the amplification status at different temperatures. RESULTS: SB-ASA was successfully used to type 36 samples for four different kinds of SNPs. Typing results were completely consistent with those by directional sequencing. Proper Ta ranges of two primers were expanded respectively from 64-69 degrees centigrade to 46-66 degrees centigrade and from 60-62 degrees centigrade to 56-61 degrees centigrade by introducing a mismatch at the third 3'terminal base. CONCLUSION: SB-ASA is a simple, rapid and efficient new method for SNP typing. During allele specific PCR reaction, specific primers with a mismatch at the third 3'terminal base have more power to identify two alleles.

Alleles↗
PubMed2001

The therapeutic effects of Sheng Jing Zhong Zi Tang in treating male infertility.

Eight-seven cases of male infertility due to spermatopathy were treated with Sheng Jing Zhong Zi Tang (SJZZT [symbol: see text]) for 1-3 courses. The total effective rate was 95.40% (83/87). 56.32% (49/87) of their spouses got pregnant and the semen quality was markedly improved (P < 0.01). The results showed that the decoction could dual-directionally regulate the levels of follicle-stimulating hormone (FSH), prolan B luteinizing hormone (LH), testosterone (T), and cortisol (C).

Adult↗
PubMed2001

[Accumulation, chemical fractions and phytoavailability of Cr in tannery sludge-amended soils].

The phytoavailability of various fractions in the tannery sludge amended soils was investigated employing a sequential extraction procedure as well as seedling culture experiment. The results showed that 2 mol/L HCl extractable Cr could be the major fraction of soil Cr available to the plants. When the Cr content in soil was about 220 mg/kg, the Cr concentration of in plant reached maximum of 23.5 mg/kg, which was hardly approachable in field condition.

Chromium↗
PubMed2001

Fas ligand expression by neoplastic T lymphocytes mediates elimination of CD8+ cytotoxic T lymphocytes in mycosis fungoides: a potential mechanism of tumor immune escape?

Mycosis fungoides (MF) is the most common form of cutaneous T-cell lymphoma (CTCL) and arises from the accumulation and clonal proliferation of epidermotropic, CD4+/CD45RO+ (helper/memory) T lymphocytes. Loss of CD8+ CTLs within MF lesions is associated with poor prognosis and disease progression. Because T-lymphocyte apoptosis is controlled mainly through the Fas/Fas ligand (FasL) pathway and tumor cells may escape immune surveillance by expressing FasL, triggering apoptosis of tumor-infiltrating T lymphocytes, we studied the role of this system in MF. T-cell subsets, Fas/FasL expression, and apoptosis were evaluated in normal and lesional skin biopsy specimens from 21 patients with all stages of MF and in cultured CTCL cell lines (MJ, HUT78, and HH) using immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and Western blotting. MF lesions and paired, clinically "normal," uninvolved skin showed increased numbers of both TUNEL-positive epidermal keratinocytes (n = 13; F = 31.146; P < 0.01, ANOVA) and dermal lymphocyte infiltrates (n = 13; F = 15.825, P < 0.01, ANOVA) compared with the normal control skin. FasL expression was highest in lesional epidermal keratinocytes, in CTCL tumor cell lines, and in dermal tumor lymphocytes in MF lesions compared with uninvolved skin. FasL colocalized with CD45RO+ cells. CD8+ cells in or adjacent to CD45RO+ cells were positively labeled by TUNEL for apoptosis. In addition, CD8+ cell numbers were decreased in areas in which FasL+ tumor cells were abundant (2.01 +/- 0.86%) compared with non-FasL expressing areas (13.53 +/- 3.54%; P < 0.02). These results suggest that a potential mechanism of tumor immune escape in MF is FasL-mediated apoptosis of infiltrating CD8+ CTLs.

Adult↗
PubMed2001

[The study of PAI-1 promotor region gene polymorphism in cerebrovascular disease].

OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor-1(PAI-1) gene polymorphism and cerebrovascular disease and detect whether it plays an important role in the pathogenesis of cerebrovascular disease. METHODS: Peripheral blood leukocytes samples were collected from 60 normal controls, 65 patients with acute cerebral infarction (CI) and 31 hypertensives complicated with cerebral hemorrhage. The 4G/5G allele polymorphism in the PAI-1 gene promotor region of the leukocytes was genotyped by polymerase chain reaction. The plasma PAI-1 activity was assayed by ELISA. RESULTS: The plasma PAI-1 activity level in the CI group was significantly higher than those in the other two groups. PAI-1 level in 4G allele homozygous genotype was significantly higher than the PAI-1 levels in 4G/5G heterozygous and 5G homozygous. Although PAI-1 level was higher in 4G/5G heterozygous genotype than in 5G homozygous, the difference was not statistically significant. There were significant differences between acute cerebral infarction PAI-1 gene polymorphism and controls (P<0.05), and the frequencies of 4G/4G genotype in patients with acute cerebral infarction (43.08%) were higher than those in normal controls (20.00%, P<0.05). There were no significant differences between hypertensives complicated with hemorrhage (25.81%) and controls (P>0.05), and the PAI-1 levels of the 4G/4G genotype in the female patients with CI were higher than those in the male patients with CI of the same genotype. CONCLUSION: The results suggest that PAI-1 gene polymorphism may be a susceptible factor to acute cerebral infarction in Chinese, and 4G allele homozygous genotype may be the major risk factor for acute cerebral infarction, and it may be especially an independent risk factor of cerebral infarction in female patients.

Cerebral Hemorrhage↗
PubMed2001

[Progress in researches on the molecular genetics of facioscapulohumeral muscular dystrophy].

Facioscapulohumeral muscular dystrophy(FSHD) is an autosomal dominant neuromuscular disorder characterized by progressive weakness of the facial, shoulder and upper arm muscles. The major gene involved has been mapped to chromosome 4q35. There is the evidence for genetic heterogeneity. The FSHD- associated DNA rearrangements are due to deletions of integral copies of the 3.3 kb tandem repeated unit from the subtelomeric region on chromosome 4q35. A valuable molecular diagnostic test for FSHD has been created with the use of p13E-11 probe to detect the EcoR I/Bln I double digestion fragment which is usually smaller in FSHD patient than in normal indivdual. Since the FSHD gene has not been identified yet, the exact molecular pathogenesis of FSHD remains unclear. The hypothesis of position effect variegation has been postulated as the underlying genetic mechanism of FSHD. FRG1 (FSHD region gene 1) from human chromosome 4q35 is identified as a candidate gene for FSHD. A significant correlation between the size of rearrangements associated with FSHD and the clinical phenotype has been found. The various rearrangement fragment size may explain the wide range of clinical severity in FSHD.

Chromosome Mapping↗
PubMed2001

[An improved auto-correlation method for Doppler fetal heart rate measurement].

It is very important to monitor the fetal heart rate in the clinical management of pregnancies antenatally. The most commonly employed non-invasive method uses Doppler ultrasound. Because of the complexity of Doppler fetal signals, the signal processing is difficult. In this paper, we describe an improved method for the determination of fetal heart rate from Doppler ultrasound signals. Using an exponentially weighted auto-correlation technique with an automatic adaptation algorithm, we have developed the method which can provide accurate fetal heart rate records, especially in the cases of reduced signal and loss of signal.

Algorithms↗
PubMed2001

The role of NDR1 in avirulence gene-directed signaling and control of programmed cell death in Arabidopsis.

Arabidopsis plants containing the ndr1-1 mutation are incapable of mounting a hypersensitive response to bacteria carrying avrRpt2, but show an exaggerated cell death response to bacteria carrying avrB (Century et al., 1995). We show here that ndr1-1 plants are severely impaired in induction of systemic acquired resistance and PR1-driven transcription of a reporter gene in response to Pseudomonas syringae strains carrying avrRpt2 but not in response to P. syringae carrying avrB. The ndr1-1 mutation also impaired salicylic acid (SA) accumulation in response to treatments that produced reactive oxygen species (ROS) and impaired induction of systemic acquired resistance in response to in situ production of ROS. Hydrogen peroxide accumulated in wild-type Arabidopsis leaves beginning 4 to 7 h postinoculation with P. syringae carrying either avrRpt2 or avrB. In ndr1-1 plants, P. syringae carrying avrRpt2 elicited no detectable hydrogen peroxide production. Hydrogen peroxide production in response to bacteria carrying avrB was similar to that of Columbia in kinetics but of lesser intensity at early time points. These data are interpreted to indicate that NDR1 links ROS generation to SA production and that the phenotypic consequences of the ndr1-1 mutation are caused by a reduced ability to accumulate SA upon pathogen infection.

Apoptosis↗
PubMed2001

[A case-control study on attempted suicide].

OBJECTIVE: To assess the independent risk factors of attempted suicide and the importance of mental illness as a risk factor. METHODS: Detailed assessments of 152 suicide attempters treated in general hospitals and 152 matched controls through questionaires. RESULTS: The rate of mental illness in the suicide attempters' group was significantly higher than that in the control group (37.7% versus 4.0%, paired Chi square = 45.45, P < 0.001). Conditional logistic regression identified three independent predictors of suicidal behavior: severe acute stress (OR = 67.47, 95% CI: 8.85-514.56), presence of mental illness (OR = 13.85, 95% CI: 2.01-95.55), and immense psychological effect of negative life events in the prior year (OR = 5.30, 95% CI: 1.12-26.08). CONCLUSION: Mental illness is an important risk factor of attempted suicide, but not an essential pre-condition of suicide attempts. It is important to establish a national suicide prevention plan that which is pertinent to the conditions in China.

Adult↗
PubMed2001

Effects of recombinant human basic fibroblast growth factor on restenosis after arterial endothelial injury in rats.

AIM: To study the preventive effect of recombinant human basic fibroblast growth factor (rh-bFGF) on restenosis after percutaneous transluminal coronary angioplasty (PTCA). METHODS: Sixty male Wistar rats were randomly divided into sham operation group, intima injured group, and intima injured plus rh-bFGF treated group. Rat carotid arteries were injured using a balloon catheter except sham operation group. The rats of rh-bFGF treated group were injected im rh-bFGF 10 kU . kg-1 . d-1 after intima was injured. Ten rats in each group were killed on d 7 and d 14 after injury, respectively. [3H]Thymidine incorporation assay and pathological examination were carried out to each vessel. RESULTS: (1) Seven days after injury, the average intimal thickness in sham operation group, intima injured group, and rh-bFGF treated group was (7 +/- 1), (32 +/- 11), and (17 +/- 3) micron; average intimal area was (384 +/- 145), (1530 +/- 817), and (586 +/- 185) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 146 +/- 18, and 105 +/- 26; the ratio of the collagen area to intimal area plus medial area were 0.29 +/- 0.09, 0.7 +/- 0.3, and 0.30 +/- 0.14; [3H]thymidine incorporation were (17 +/- 6), (62 +/- 23), (20 +/- 8) kBq/g tissue, respectively. (2) Fourteen days after injury, the average intimal thickness of sham operation group, intima injured group, and rh-bFGF treated group was (8 +/- 1), (41 +/- 9), and (20 +/- 3) micron; average intimal area was (391 +/- 134), (1761 +/- 337), and (731 +/- 124) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 145 +/- 9, and 102 +/- 6; the ratio of collagen area to intimal area plus medial area were 0.28 +/- 0.14, 0.59 +/- 0.21, and 0.38 +/- 0.03; [3H]thymidine incorporation was (15 +/- 4), (57 +/- 11), and (22 +/- 6) kBq/g tissue, respectively. CONCLUSION: Large dosage of rh-bFGF inhibits neointimal hyperplasia and reduces restenosis after balloon injury.

Angioplasty, Balloon, Coronary↗
PubMed2001

Matrine inhibits production and actions of fibrogenic cytokines released by mouse peritoneal macrophages.

AIM: To study the effects of matrine (Mat) on production and actions of fibrogenic cytokines from mouse peritoneal macrophages. METHODS: Mouse peritoneal macrophages were primed with calcimycin 1 micromol/L for 8 h then elicited by lipopolysaccharides (LPS) 100 microg/L for 6 h to induce fibrogenic cytokines. Proliferative and collagen stimulating activity in the macrophage culture supernatants was determined by crystal violet staining assay and [3H]-proline incorporation assay using rat hepatic stellate HSC-T6 cell or mouse fibroblast NIH3T3 cell. Transforming growth factor beta (TGFbeta) activity was measured by [3H]-thymidine incorporation assay using Mv-1-Lu mink lung epithelial cell. RESULTS: Mat (0.5-2 mmol/L) was shown to significantly inhibit LPS-induced collagen stimulating activities and TGFbeta production (P < 0.01) whereas did not inhibit proliferative activities induced by macrophages. Macrophage conditioned medium (MCM)-driven proliferation and collagen synthesis of HSC-T6 cells as well as NIH3T3 cells were attenuated by Mat (0.5-2 mmol/L) in a concentration-dependent manner. CONCLUSION: Antifibrotic effects of Mat on hepatic stellate cells may be related to reduction of fibrogenic cytokine production and blockade of their actions.

Alkaloids↗
PubMed2001

[State of soil available sulphur and its requirement along Huaihe River region].

This paper investigated the available S contents of yellow cinnamon soil, fluvisol, shajiang black soil and paddy soil, which were developed from loessial ancient-river alluyium, recent loess-flooding deposit, and Xiashu loess. The input and output, and the abundance and deficiency of soil available S were studied in combination with the mode of land utilization and fertization, and the soil demands of S was predicted. The results showed that the content of soil available S was decreased in the order of paddy soil > shajiang black soil > yellow cinnamon soil > fluvisol, and there was more S in irrigated land than in dry field in case of different land utilization. From the viewpoint of parent material, the deficiency frequency of soil available S was in the order of loessial ancient-river alluvium > Xiashu loess > recent loess-flooding deposit, and the potential deficiency frequency of S was loessial ancient-river alluvium > recent loess-flooding > Xiashu loess. As for soil type, the deficiency frequency of soil available S was in the order of deposit shajiang black soil > yellow cinnamon soil > fluvisol > paddy soil, and the potential deficiency frequency of S was paddy soil > fluvisol > shajiang black soil > yellow cinnamon soil. Shajiang black soil had the largest area of lacking available S, which amounted to 7.0 x 10(4) hm2, yellow cinnamon soil had an area of 2.0 x 10(4) hm2, and fluvisol was 6000 hm2. The total area of lacking S was 9.6 x 10(4) hm2, accounted for 25.06% of total cultivated area. The total area of potentially lacking S was 1.6 x 10(5) hm2, accounted for 42.04% of the total. According to the current available S content in soils and the S demands for high yielding crops, the S demands of 3.8 x 10(5) hm2 farmland in three counties and one district of Bengbu was about 3.0 x 10(6) kg and 1.2 x 10(6) kg in the recent and far future, respectively.

Fertilizers↗
PubMed2001

[An off site petroleum-contaminated soil bioremediation technology: soil compositing in windrow].

With off-site bioremediation technology, a soil contaminated by crude oil from Liaohe Oil Field was treated on a 20 x 10 m prepared bed. 8 composting windrow units were set, each measured 8 m in length, 2 m in width, and 0.35 m in height. The results showed that when the pollutant petroleum hydrocarbon(TPH) was within the range of 4.16-7.72 g.100 g-1 soil, the total degradation rate of TPH reached 45.19%-56.74% after 53 days operation, which indicated that a technological basis would be provided for the bioremediation of oil-contaminated soil.

Biodegradation, Environmental↗
PubMed2001

[Pathological observation of 16 cases with non-epithelial tumor and tumor-like lesions of the prostate].

OBJECTIVE: To investigate the diagnosis, differential diagnosis and prognosis of stromal tumors and tumor-like lesions of the prostate. METHODS: By means of HE, immunohistochemistry and electron microscopy, the clinical and histological data of 16 cases with stromal tumors and tumor-like lesions of the prostate were observed. Some of them were followed-up. RESULTS: Of the 16 cases, 6 presented stromal nodular hyperplasia, 3 were stromal sarcoma, 1 malignant phyllodes-type tumor, 3 leiomyosarcoma, 1 fibrosarcoma, and one non-Hodgkin's lymphoma. CONCLUSIONS: Nearly all the leiomyomas of the prostate diagnosed previously are, in fact, stromal nodular hyperplasia. The phyllodes-type tumors are often confused with stromal sarcomas in needle biopsy specimens and cause difficulty in differential diagnosis. Diagnostic criteria of leiomyosarcoma, fibrosarcoma, non-Hodgkin's lymphoma of the prostate are the same as their counterparts in the soft tissue. Non-epithelial malignant tumors in prostate are of poor prognosis.

Aged↗
PubMed2001

[Changes of photosynthetic characteristics of strawberry leaf under shading].

Studies on the photosynthetic characteristics of two strawberry varieties (Baojiaozaosheng and Shuofeng) under shading showed that the photosynthesis rate decreased by 20% and 47%, when the apparent quantum efficiency increased by 13% and 8%, respectively. The chlorophyll content was enhanced slightly, while the insoluble protein content in leaf decreased drastically. The results also showed that the PSII activity decreased by 22.5% and 53.7%, and the activity of Rubisco, the key enzyme of Calvin cycle, decreased by 19.6% and 35.5%, respectively. The reason of photosynthesis rate descent in light saturation point was also discussed.

Light↗
PubMed2001

[Effect of long-term single application of chemical fertilizer on soil properties and crop yield].

A long-term located experiment showed that single application of chemical fertilizer basically sustained the quantity level of soil organic matter, nitrogen and phosphorous, reduced the energy level of soil humus and enhanced its condensation degree, aromaticity and aging function. The corp yield was basically the same as that of combined application with organic manure.

Crops, Agricultural↗