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D Cao

Publications and source records attributed to D Cao.

At least 55 records · Page 3Linked to original sources
PubMed2000

[The construction of PQE-ARL-1 recombinant expression plasmid and the preparation and purification of ARL-1 protein].

OBJECTIVE: To further understand the function and biological activity of aldose reductase like-1 (ARL-1), and to provide the basis for the preparation of the specific antibody against ARL-1. METHODS: The ARL-1 cDNA was cloned into procaryotic expression vector PQE-30 and the recombinant ARL-1 expressed in E.coli M(15); then Ni(+)-NTA agarose columns were used to purify the ARL-1 protein. RESULTS: With the digestion of the enzymes, we identified that the ARL-1 gene was inserted into the procaryotic expression vector PQE-30. The expression products of PQE-ARL-1 (human recombinant ARL-1) showed a single protein band on SDS-PAGE. The molecular weight of ARL-1 was approximately 37.7 x 10(3) and the expression level was about 25% of the total bacterial protein. The concentration of ARL-1 protein was about 100mg/L. CONCLUSION: The construction of the recombinant plasmid PQE-ARL-1 and the preparation of the protein ARL-1 have laid a solid foundation for further studying the function of ARL-1 and preparing the specific antibody against ARL-1.

Aldehyde Reductase↗
PubMed2000

[Surgical treatment and prognostic analysis of 39 cases invasive vulvar cancer].

OBJECTIVE: To summarize the procedure of operations and evaluate the prognostic factors in the invasive vulvar cancer. METHODS: Thirty nine cases with invasive vulvar cancer admitted in our hospital from 1979 to 1997 were retrospectively analyzed. Three kinds of operations were used: 5 by local excision, 13 by modified radical vulvectomy and 21 by radical vulvectomy. Statistical package for social sciences (SPSS) was used to compare the different strategy of operation and analyze the prognostic factors. RESULTS: Thirty three patients (84.6%) had squamous cell carcinoma and 26 of them (78.8%) were well differentiated and 2 poorly differentiated. Seven cases (17.9%) were in FIGO stage I; 17 (43.6%) in stage II; 13 (33.3%) in stage III, and 2(5.1%) in stage IV, 58.3% of tumor in stage I and II were lateral while 73.3% of tumor in stage III and IV were median type. Hospitalization time for local excision, modified radical vulvectomy and radical vulvectomy (separated and en-bloc incision) were 9.1, 20.6, 41.2 and 62.2 days (P < 0.01) and the incision infection rate were 0%, 30.8%, 66.7% and 88.9% (P < 0.01) respectively. Median survival time for stage I, II, II and IV were 132.0, 121.5, 67.5 and 21.5 months (P = 0.01) and the 5-year survival rates of them were 85.7%, 70.6%, 46.2% and 0.0% (P < 0.05) respectively. Median survival time for patients with or without lymph nodes involvement were 66.0 and 121.5 months (P < 0.01) and the 5-year survival rates were 30.0% and 71.5% (P < 0.05) respectively. Median survival time for well or poor differentiation were 97.0 and 64.0 months (P > 0.05) and the 5-year survival rates were 62.0% and 43.0% (P > 0.05) respectively. CONCLUSIONS: The important prognostic factors for invasive vulvar cancer were sites(lateral/median), stage, differentiation and lymph nodes involvement. Individualized treatment should be considered.

Adult↗
PubMed2000

[Preliminary study on relationship between antibody against heat stress protein 70 and hypertension].

OBJECTIVE: To preliminarily explore the relationship between main antibody against heat stress protein 70 (anti-HSP70) and hypertension. METHODS: Serum anti-HSP70 was determined with Western blotting technique in hypertensive and normotensive groups. Logistic regression model was used to analyze the relationship between anti-HSP70 and hypertension. RESULTS: It was found that level of antibody against the main heat shock protein 70 was significantly higher in patients with hypertension (based on criteria of 160/95 mm Hg, 1 mm Hg = 0.133 kPa) than in controls, after adjustment for the generally recognized risk factors for hypertension (such as age, sex, length of employment, body mass index, job, et al.). There still was stronger association between anti-HSP70 and hypertension (based on criteria of 140/90 mm Hg), but its strength of association was weaker than the former. CONCLUSIONS: Anti-HSP70 may potentially serve as a serum biomarker to assess hypertension, or anti-HSP70 itself may be involved in the development of hypertension.

Autoantibodies↗
PubMed1999

Early repair treatment of electrical burns and recovery of tendons and nerves. Report of 194 operations.

A new approach to treatment of electrically burned tendons and nerves by primarily covering with skin or myocutaneous flaps is recommended. Between 1964 and 1989, 194 operations using the new approach were performed on 147 patients, of which 179 operations were successful and only 15 procedures resulted in infection. Among 42 cases involving the wrist, the rate of functional recovery of the electrically burned tendons was 97.6%; the rate of recovery in 21 cases of electrically burned peripheral nerves was 80.9%.

Burns, Electric↗
PubMed1999

Genomic structure, chromosomal mapping, and promoter region analysis of murine uridine phosphorylase gene.

Uridine phosphorylase (UPase) plays an important role in the activation of 5-fluorouracil and in the regulation of tissue and plasma concentration of uridine, a potential biochemical modulator of 5-fluorouracil therapy. UPase expression is affected by the c-H-ras oncogene and various cytokines through unknown mechanisms. To understand its expression and regulation, we cloned the murine UPase gene, defined its genomic organization, determined its 5'- and 3'-end flanking sequences, and evaluated the promoter activity. The UPase gene contains nine exons and eight introns, spanning a total of approximately 18.0 kb. Its promoter lacks canonical TATA and CCAAT boxes, although a CAATAAAAA TATA-like box is seen from -41 to -49. Furthermore, IFN regulatory factor 1, c/v-Myb, and p53 binding sites are present in the promoter region, indicating that UPase expression may be directly regulated by cytokines and oncogene products. The 1.2-kb flanking fragment showed promoter activity driving the expression of the luciferase gene in various mammalian cells. A TGGGG repeat sequence is seen in the 3'-end flanking region. This element is considered to be a potential recombination consensus hot spot that may contribute to the encoding of different UPase isoforms present in different tissues, both normal and neoplastic.

3' Untranslated Regions↗
PubMed1999

[Changes and significance of natural killer cell, IL-2, IL-6 and TNF alpha of heroin addicts after detoxification].

In order to find out the activity of NKC and production of IL-2 in the peripheral blood mononuclear cells and the level of IL-6 and TNF alpha in the peripheral blood serum, we investigated 51 herion addicts who were in the course of detoxification. MTT colorimetric assay and ELISA assay methods were adopted. The results showed that, in the herion addicts, NK activity was 30.11 +/- 5.2%, IL-2 activity was 8.06 +/- 1.66 IU/ml, IL-6 level was 61.17 +/- 12.07 pg/ml, and TNF alpha level was 91.83 +/- 19.19 pg/ml, whereas in the healthy controls, the results were 44.89 +/- 4.75%, 15.91 +/- 3.83 IU/ml, 22.18 +/- 9.31 pg/ml and 30.55 +/- 11.94 pg/ml respectively. When the herion addicts were subjected to detoxication, their NKC and IL-2 activities, IL-6 and TNF alpha levels gradually restored to normal, and were correlated with the time of their detoxification (NKC: r = 0.626, P < 0.001; IL-2: r = 0.684, P < 0.001; IL-6: r = -0.791, P < 0.001; TNF alpha: r = -0.703, P < 0.001).

Adult↗
PubMed1999

[A pathological study on pulmonary fibrosis caused by chronic obstructive pulmonary disease].

OBJECTIVE: To estimate the morphologic characteristics of chronic obstructive pulmonary disease (COPD) induced pulmonary fibrosis. METHODS: 41 autopsy cases of COPD were chosen as the study group and other 10 autopsy cases died from non-respiratory diseases as control group. Histochemical stain and image quantitative analysis were used to identify the type of collagen. RESULTS: In 36 cases (88%) of study group, fibrosis proliferation could be seen in peri-bronchial area, especially in the bronchi under grade VI. Respiratory bronchiole and alveoli were also involved in 11 cases. The main component of collagen in fibrosis area was identified as type III collagen by sirius red stain, reticular fiber could also be seen by Gomori stain. The type III collagen in alveoli distributed interruptedly. Image quantitative analysis showed: the integral optical density (A) of type III collagen was much higher than that of type I collagen in peri-bronchial area (P < 0.01); Both A of type III and type I collagen in peri-bronchial area were higher than that in alveolar area (P < 0.01). Mucous purulent plugs, interrupted elastic fibers in bronchial wall and chronic inflammation accompanied with lymphocytes infiltration in fibrosis area could also be seen. CONCLUSIONS: COPD induced pulmonary fibrosis distributed mainly in peri-bronchial area, especially in the bronchi under grade VI. The main component of proliferative collagen was type III collagen. The genesis of pulmonary fibrosis might be associated with chronic inflammation accompanied with lymphocytes. Peri-bronchial fibrosis, interrupt of elastic fibers in bronchial wall caused the bronchial lumen narrowed or collapsed making both airway obstruction and ventilation insufficiency deteriorated.

Aged↗
PubMed1999

[Tissue specificity and expression of a human sperm protein's gene BSD-2.4].

OBJECTIVE: To investigate the tissue specificity and expression in spermatogenic stage of BSD-2.4 cDNA which might be related with fertility and its sequence was received by GenBank. METHODS: Dot blot, Northern blot, and in situ hybridization were used. RESULTS: Northern blot analysis of sixteen human tissues showed that BSD-2.4 cDNA had one transcript only with testis. BSD-2.4 mRNA was detected in germ cells of human testis. CONCLUSIONS: BSD-2.4 is a testis-specific protein. The cDNA was expressed throughout the stages of the spermatogenic cycle.

Animals↗
PubMed1999

[The characterization of a novel testis-specific nucleoporin gene].

OBJECTIVE: To investigate the structure and function of testis-specific gene and spermatogenesis in human. METHODS: Screening cDNA expression library, 5' rapid amplification of cDNA ends, Northern blot and fluorescent in situ hybridization(FISH) were used. Gene expressing, purified of expressed protein by affinity chromatography and SDS-PAGE as well as phosphorylation of expressed protein in vitro by PKC and p34cdc2 were observed. RESULTS: A cDNA designated as BS-63 was isolated and found to consist of 2,209 bp with an open reading frame of 2,100 bp and assigned the accession number U64675 by GenBank. The deduced polypeptide consisted of 700 amino acid residues containing XFXFG or FG motifs that were characteristic of nuclear pore complex (NPC) protein and acted as potential binding sites for Ran. The N-terminal region had high homology with Ran BP2/Nup 358, a nucleoporin component, showing that BS-63 was a member of the NPC family. Northern blot analysis of mRNA prepared from various human tissues showed that BS-63 gene was transcribed in two forms: 6.0 and 8.5 kb. The 8.5 kb transcript was present in low amounts in several somatic tissues; whereas the 6.0 kb transcript was expressed only in testis. Analysis by FISH method mapped the BS-63 gene in 2q11.2-12. A protein band with an estimated Mr of 80,000 was detected with E. coli BL21 (DE3) transfected with recombinant plasmid pET30a (+)-BS-63. In vitro phosphorylation test indicated the BS-63 recombinant protein could be phosphorylated by PKC and p34cdc2. CONCLUSIONS: The study was the first demonstration that the BS-63 gene encoding a nucleoporin-related protein with Ran binding sites was expressed in germ cells of human testis.

Amino Acid Sequence↗
PubMed1999

[Study on pretreatment for the determination of several nutrition element in eggs with AAS].

In this paper, 0.1 mol x L(-1) HCl, 6 mol x L(-1) HCl, pH 7.0 1 mol x L(-1) NH4Ac was oscillated and 6 mol x L-' HCI was boilled to extract and determine K, Na, Ca, Zn, Fe, Mn, Mg and Cu. Comparing with classical method that popularly used HNO3-HCl04 to degest and ash samples,the results indicated that for macroelement K,Na and Mg several extraction methods are similar to classical method,the recovery was 90%-115%,for microelement Zn, Mn and Fe could be extracted using pH7.0 1 mol x L(-1) NH4Ac, 0.1 mol x L(-1) HCI, 6 mol x L(1) HCI oscillating,the recovery was 100%-115%. Cu could be analysed using 6 mol x L(-1) HCI boiling. But the results of Ca were not better because of the enhancement effect. The results with ash sample were lower because many elements were lost when ash temperature was up to 450 degrees C. These methods of exatraction pretreatment are simple and rapid. The recovery and precision are satisfactory.

Animals↗
PubMed1999

[Prediction the octane number of gasoline by near infrared spectra analysis].

The feasibility of predicting the octane number by the near infrared spectra analysis technique in the quantitative analysis was investigated. 12 calibration gasoline samples and 4 prediction samples were collected and their absorption spectra were measured with a high precision model Lambda 19 scanning spectrophotometer. Based on the multivariate statistic model, stagewise regression and partial least squares were selected. A model of the correlation behavior between the spectra and octane number was established and calibrated, and then the prediction of octane number is made. The prediction error is +/-1.0 octane number in the best analysis results.

Gasoline↗
PubMed1998

Expression, characterization, and detection of human uridine phosphorylase and identification of variant uridine phosphorolytic activity in selected human tumors.

Uridine phosphorylase (UPase) catalyzes the reversible phosphorolysis of uridine to uracil. We purified the enzyme from the murine colon 26 tumor using a two-step procedure through 5-amino-benzylacyclouridine affinity chromatography. Antibodies raised in rabbits against the purified protein revealed single bands in Western blots of normal human tissue and tumor extracts. The polyclonal antibody used to screen a human liver expression library allowed the isolation of a 1.2-kb clone that contained the entire open reading frame of the human UPase. The UPase cDNA has been expressed as a fusion protein in Escherichia coli using the pMal-C2 vector. The kinetic analysis demonstrated that the recombinant UPase preferentially uses uridine, 5-fluorouracil, and uracil as substrates, although lower levels of activity were observed with 2-deoxyuridine and thymidine. Clinical samples of human tumors and adjacent normal tissues were assayed for phosphorolytic activity and sensitivity to 5-benzylacyclouridine (BAU), a potent inhibitor of the enzyme presently in Phase I-II clinical trial. Activity in normal tissues appeared to be low but very sensitive to BAU (approximately 90% inhibition at 10 microM). Tumors had generally 2-3-fold greater activity compared with adjacent normal tissues. In breast cancer specimens and head-neck squamous carcinomas, however, uridine cleavage was only partially inhibited (40-60%) by 10 or 100 microM BAU. The BAU-insensitive activity requires phosphate and pH conditions similar to the normal enzyme, and the new phosphorolytic activity was independent from thymidine phosphorylase. The BAU-insensitive phosphorolytic activity in selected tumors, coupled with the potent inhibitory activity of BAU against the "classical" uridine phosphorylase in normal human tissues, provides the rationale for combining BAU with 5-fluorouracil in the treatment of breast and head-neck tumors.

Amino Acid Sequence↗
PubMed1998

Multiple heparan sulfate chains are required for optimal syndecan-1 function.

Syndecans have three highly conserved sites available for heparan sulfate attachment. To determine if all three sites are required for normal function, a series of mutated syndecans having two, one, or no heparan sulfate chains were expressed in ARH-77 cells. Previously, we demonstrated that expression of wild-type syndecan-1 on these myeloma cells mediates cell-matrix and cell-cell adhesion and inhibits cell invasion into collagen gels. Here we show that to optimally mediate each of these activities, all three sites of heparan sulfate attachment are required. Generally, an increasing loss of syndecan-1 function occurs as the number of heparan sulfate attachment sites decreases. This loss of function is not the result of a decrease in either the total amount of cell surface heparan sulfate or syndecan-1 core protein. In regard to cell invasion, cells expressing syndecan-1 bearing a single heparan sulfate attachment site exhibit a hierarchy of function based upon the position of the site within the core protein; the presence of an available attachment site at serine 47 confers the greatest level of activity, while serine 37 contributes little to syndecan-1 function. However, when all three heparan sulfate chains are present, significantly greater biological activity is observed than is predicted by the sum of the activities occurring when the chains act individually. This synergy provides a functional basis for the evolutionary conservation of the three heparan sulfate attachment sites on syndecans and supports the idea that molecular heterogeneity, which is characteristic of proteoglycans, contributes to their functional diversity.

Cell Adhesion↗
PubMed1998

Identification and characterization of a novel human aldose reductase-like gene.

We have identified a novel human protein that is highly homologous to aldose reductase (AR). This protein, which we called ARL-1, consists of 316 amino acids, the same size as AR, and its amino acid sequence is 71% identical to that of AR. It is more closely related to the AR-like proteins such as mouse vas deferens protein, fibroblast growth factor-regulated protein, and Chinese hamster ovary reductase, with 81, 82, and 83%, respectively, of its amino acid sequence identical to the amino acid sequence of these proteins. The cDNA of ARL-1 was expressed in Escherichia coli to obtain recombinant protein for characterization of its enzymatic activities. For comparison, the cDNA of human AR was also expressed in E. coli and analyzed in parallel. These two enzymes differ in their pH optima and salt requirement, but they act on a similar spectrum of substrates. Similar to AR, ARL-1 can efficiently reduce aliphatic and aromatic aldehydes, and it is less active on hexoses. While AR mRNA is found in most tissues studied, ARL-1 is primarily expressed in the small intestines and in the colon, with a low level of its mRNA in the liver. The ability of ARL-1 to reduce various aldehydes and the locations of expression of this gene suggest that it may be responsible for detoxification of reactive aldehydes in the digested food before the nutrients are passed on to other organs. Interestingly, ARL-1 and AR are overexpressed in some liver cancers, but it is not clear if they contribute to the pathogenesis of this disease.

Adult↗
PubMed1998

A pathological study of in situ thrombosis of small pulmonary arteries and arterioles in autopsy cases of chronic cor pulmonale.

OBJECTIVE: To investigate the incidence of in situ thrombosis of small pulmonary arteries and arterioles during the exacerbation stage of chronic cor pulmonale. METHODS: 49 autopsy cases died from the exacerbation of chronic cor pulmonale were chosen as the study group, while 103 other autopsy cases without chronic cor pulmonale and disseminated intravascular coagulation (DIC) as control group. Morphologic and morphometric studies were taken on lung tissues and other organs with focus on the thrombi in small pulmonary arteries and arterioles. RESULTS: 44 cases of the study group had multiple thrombi in small pulmonary arteries and arterioles, the incidence is 89.8%, and in 9 of them, thrombi in proximal pulmonary arteries co-existed, the incidence is 18.4%. 80% of the thrombi existed in pulmonary arterioles. In the control group, only 3 cases had thrombi in small pulmonary arteries and arterioles, the incidence is 2.9%. All thrombi adhered to endangium, implying that they were in situ thrombi. No intravascular thrombosis was found in other organs. chi 2 test showed that the incidence of thrombosis and the number of thrombi in small pulmonary arteries and arterioles in cases with chronic cor pulmonale were significantly higher than those of the control group (P < 0.01). CONCLUSIONS: Multiple in situ thrombosis in small pulmonary arteries and arterioles is a prominent and common pathological change during the exacerbation stage of chronic cor pulmonale. The study suggests a new diagnostic and therapeutic concept and gives a morphological and theoretical basis for the clinical application of anticoagulants or even the thrombolytic agents for the cases of chronic cor pulmonale in the exacerbation stage.

Aged↗