Biomedical subjects

Q Luo

Publications and source records attributed to Q Luo.

At least 37 records · Page 2Linked to original sources

PubMed2001

[Study on the removal of arsenite from dispersed drinking water].

The feasible methods for oxidation and removal of arsenite[As(III)] from dispersed drinking water were based on the removal of arsenate[As(V)] by ferric sulfate. The results showed that the spotaneous oxidation of As(III) to As(V) was very slow and could not be enhanced by aerating for 24 h. The removal rate of As(III) could reach that of As(V) when pre-aerating water samples with ozone for 60 s, putting 7.5 ml/L hydrogen peroxide solution, adding 2.5 mg/L javelle water (sodium hypochlorite) or 15 mg/L bleaching powder(numerated by chlorine). The oxidation by using javelle water was rather stable when samples were varied in pH value, hardness, initial concentration of As(III) and As(III)/As(V) ratio. The effective oxidation could be reached with 1.25 mg/L javelle water when the initial concentration of As(III) was < or = 0.8 mg/L. Moreover, the field study also confirmed the oxidation effect of javelle water. It is suggested that javelle water is an effective, economic and technologic feasible oxidationagent for removing arsenite from dispersed drinking water.

Arsenites↗

PubMed2001

[Release character of phosphorus from the sediments of east Lake, Wuhan].

Effects of environmental factors on the release of phosphorus were studied at laboratory simulated test. The relationship between the different forms of phosphorus in sediments and the quantity of releasing phosphorus was studied at the same time. Results showed that the rates of phosphorus release from the sediment increased with rising the temperature of disturbing the overlying water. The content of phosphorus release from the sediment reached the lowest level when pH value was 7.4, high pH or low pH increased the rates of phosphorus release from the sediment. In anaerobic, the release rates of phosphorus was 30 times as much as in aerobic. Research also showed that different chemical forms of phosphorus in sediments were related to the quantity of phosphorus released from the sediments in varying degrees. The dissolved phosphorus and Fe binding phosphorus in sediments played the most important roles (r > 0.90, P < 0.01).

China↗

PubMed2001

Novel expression patterns of the myc/max/mad transcription factor network in developing murine prostate gland.

PURPOSE: Expression of myc proto-oncogenes and myc-antagonizing mad/mxi genes typically predominate in proliferating versus differentiating cells, respectively. C-myc expression in prostate cells is well established but to our knowledge that of several recently discovered mad/mxi genes is completely uncharacterized. Such characterization is particularly relevant because mxi1 is lost or mutated in some human prostate tumors and mouse mxi1-null mutants show prostatic hyperplasia. MATERIALS AND METHODS: Developing murine prostatic lobes at select postnatal days 1 to 28 were analyzed by in situ immunohistochemical and in vitro RNA analysis. The expression patterns of the 3 myc genes c-, L- and N-myc, and the mad1, mxi1 and mad4 genes were studied in most detail with nonradioactive in situ and immunohistochemical analyses. RESULTS: We describe what is to our knowledge previously unreported expression of N- and L-myc in the prostate with particularly the latter strongly expressed throughout development. High c-myc expression was lost at day 7 with re-elevation at day 14, followed by subsequent low expression, representing a unique in vivo confirmation of c-myc expression changes seen previously in several in vitro differentiation systems. The alternatively spliced weak and strong repressor mxi1 isoforms showed distinct, partially overlapping expression patterns. Of particular interest were continual mad1 and mad4 expression during the proliferative and differentiative phases. Similarly mad1 was evident in proliferating normal prostate cell cultures but not in tumor cell lines, suggesting that mad1 expression in prostate may be clinically relevant. CONCLUSIONS: Myc network expression in developing mouse prostate is novel and does not completely fit previous simpler models of Myc versus Mad expression based on other cell types.

Animals↗

PubMed2001

[Removal of arsenic from dispersed drinking water by iron oxide-coated sand].

The iron oxide-coated sand(IOCS) was developed by treating normal river sand with molysite and investigated by batch, column tests and autoptic experiment to evaluate it's ability of eliminating arsenic from dispersed drinking water. The results showed that IOCS was relatively stable and can be seen iron oxide distributedly patched the surface of sand by scan electron microscope. IOCS needn't any activation pretreatment. It reached the maximum adsorption within 30-60 min. The removal percentage of arsenate was decreased but the one of arsenite had little change when the pH varied from 5 to 9. And the arsenic adsorption matched the Langmuir isotherm. In 5 circles of runs, it treated 408-426 (arsenite) beds and 390-412(arsenate) beds volume of water with 75 g(50 ml) IOCS respectively when the influent arsenic concentration was 1.0 mg.L-1. And the arsenic percentage recovery was above 94% when regenerating the IOCS by 0.2 mol.L-1 NaOH. The home simulation unit contained IOCS 3.0 kg produced 209 L and 198 L, 196 L and 185 L of water when the influent arsenate or arsenite concentration was 1.0 mg.L-1, and 200 L arsenic free water with the influent arsenic 0.202-1.733 mg.L-1 during the field experimental period. The water quality was not affected by the adsorbent. With low-cost and simple operation, the IOCS should be a promising novel medium for arsenic removal in dispersed drinking water.

Adsorption↗

PubMed2001

[The effect of rhIL-11 on hematopoiesis of rhesus monkeys irradiated with 60Co gamma-rays].

OBJECTIVE: To study the therapeutic effect of recombinant human interleukin-11 (rhIL-11) on acute radiation sickness in monkeys. METHODS: rhIL-11 (30, 60, 120 micrograms.kg-1.d-1, s.c., on days 0-13 after TBI) or vehicle was administered to rhesus monkeys irradiated with 3.0 Gy 60Co gamma-rays. RESULTS: The nadirs of platelet count were significantly improved after treatment with rhIL-11. The duration of platelet and leukocyte numbers below 50% of their baseline values was shortened. Erythrocyte recovery was also accelerated. Semi-solid bone marrow cell culture demonstrated that rhIL-11 could stimulate monkey's bone marrow cell to form more CFU-MK, CFU-Mix, CFU-E and BFU-E in vitro, especially at the dose of 60 micrograms.kg-1.d-1. Histopathological observation revealed that bone marrow of the untreated controls showed large area of bleeding whereas that of the rhIL-11 treated monkeys was in active proliferation. CONCLUSION: rhIL-11 can accelerate hematopoietic recovery of monkeys received 3.0 Gy total body gamma-rays irradiation.

Animals↗

PubMed2001

[An new filling material of hair for the application of plastic surgery].

OBJECTIVE: To investigate the possibility of hair as a filling material for reconstructive or cosmetic surgery. METHODS: Sterilized pellets of hairs and silicone were selected and implanted subcutaneously in white rabbits. The clinical trial was carried out in 3 cases. RESULTS: A thin fibrous capsule, with much few inflammatory cells, was formed around the implanted hair pellets in 3-4 months. The inflammatory cells disappeared in the 9th month. No implant rejection, granulomatous formation or hair degradation was showed. CONCLUSION: Hair may be a valuable filling material for augmentation of the soft tissue.

Adult↗

PubMed2001

[A study of adhesion molecule expression in extraocular muscles of Graves' ophthalmopathy].

OBJECTIVE: To investigate the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) in extraocular muscles (EOM) of the eyes with Graves' ophthalmopathy (GO). METHODS: Seventeen EOM specimens obtained from 16 severe patients with GO and their cryostat sections were observed by double labeling immunohistochemical methods. RESULTS: The expression of ICAM-1 was observed in interstitial and perimysial connective tissue surrounding EOM fibers, mononuclear cells, fibroblasts and vascular endothelial cells. Only were vascular endothelial cells stained for VCAM-1, and ICAM-1 and VCAM-1 immunoreactivities were not detected in EOM cells. CONCLUSIONS: The findings indicate that ICAM-1 and VCAM-1 might be involved in the development of GO, and fibroblasts, vascular endothelial cells and mononuclear cells might play important roles in the autoimmune reaction.

Adult↗

PubMed2001

[Modification of membrane lipid of human umbilical vein endothelia cells after direct lipopolysaccharide injury].

Our previous study showed that the membrane viscosity of human umbilical vein endothelial cells (HUVECs) increased with lipopolysaccharide (LPS) concentration after direct LPS damaging, implying that LPS could change the membrane structure and composition of HUVECs. The purpose of the present study was to investigate the modification of HUVECs membrane lipid by LPS under direct LPS injury to HUVECs. Phospholipid components of HUVEC membrane were determined with high performance capillary electrophoresis (HPCE), and HUVECs were directly damaged by LPS of different concentrations: 0, 0.313, 0.625, 1.25, 2.5, 5 and 10 microgram/ml for 3 h, and by 0.625 microgram/ml for 1, 3, 6, 12, 24 and 48 h. The results show that total phospholipid content of HUVECs increased with the increase of LPS concentration at 3 h, and decreased with the duration of LPS effect at 0.625 microgram/ml. Phosphatidylinositol (PI) and phosphatidylcholine (PC) contents increased with the increase of LPS concentration and decreased with the duration of LPS effect; LPS contents and its effect duration had slight effect on sphingomyelin (SM), phosphatidylethanolamine (PE) or phosphatidylserine (PS) contents. The LPS activating effect of HUVEC membrane lipid showed a typical property of enzymatic dynamics. These experimental results indicate that LPS directly activates the metabolism of HUVEC membrane lipid and induces the modification of HUVEC membrane phospholipid, which implies that the mechanism of the impairment of HUVECs by LPS may be related to the membrane structure of HUVECs and the metabolism of HUVEC membrane lipid.

Cells, Cultured↗

PubMed2001

[Factors affecting arsenic removal with copolymer coagulant and their mechanism].

The removal of arsenic from drinking water with copolymer coagulant was investigated. The effect of the component, additive substance of the coagulant and filtration were tested by employing a orthogonal analysis. The results showed that the arsenic removal with ferric sulfate was better than that with ferric-aluminum copolymer and polysilicon metal salt. Adding active carbon powder or kaoline could not enhance the efficacy of arsenic removal. However, the removal rate was improved by filtration after using coagulates, and sand filtration was feasible. The efficacy of arsenic removal could be affected by the column height filled with sand and the diameter of sand. After arsenic adsorption model fitted, the Lang-muire isotherm was matched. The main mechanism of arsenic removal by coagulation should be adsorption.

Adsorption↗

PubMed2001

[Field study on the removal of arsenic from dispersed drinking water].

Shanyin county, an area prevalent of endemic arsenic poisoning in Shanxi Province, was selected as the experimental field to verify the methods studied for removal arsenic from dispersed drinking water. The results showed that the desired goal has been achieved from the field study. The results confirmed that arsenate could be removed from drinking water by using ferric sulfate or aluminum sulfate as coagulants and employing sand filtration. Javelle water(sodium hypochlorite) is an effective oxidant for arsenite. The performance of iron oxide-coated sand developed in this study was good for arsenic removal. Further study and application is needed.

Arsenic↗

PubMed2000

Phytic acid as an efficient low-molecular-mass displacer for anion-exchange displacement chromatography of proteins.

Phytic acid, inositol-hexaphosphoric acid, molecular mass 650, a low-molecular-mass compound, has been identified as a nearly ideal displacer in anion-exchange displacement chromatography for the concentration and purification of model protein mixture. The concentration of low-molecular-mass displacer is a very important parameter for successful separation by displacement chromatography. Displacer concentration influences the formation of the isotachic train and the yield and recovery of the displacement chromatographic process. There is an optimum displacer concentration in which the yield and recovery are highest.

Anion Exchange Resins↗

PubMed2000

[Isolation and purification of Lycium barbarum polysaccharides and its antifatigue effect].

A purified component of lycium barbarum polysaccharide (LBP-X) was isolated from lycium barbarum L. by DEAE ion-exchange cellulose and sephacryl gel chromatography. LBP-X was tested on five different doses (5, 10, 20, 50 and 100 mg.kg-1.d-1) in mice. The results showed that LBP-X induced a remarkable adaptability to exercise load, enhanced resistance and accelerated elimination of fatigue. LBP-X could enhance the storage of muscle and liver glycogen, increase the activity of LDH before and after swimming, decrease the increase of blood urea nitrogen (BUN) after strenuous exercise, and accelerate the clearance of BUN after exercise. The dosage of LBP-X 10 mg.kg-1.d-1 was the best amount among the five tested doses.

Animals↗

PubMed2000

Cellular delivery of functional peptides to block cytokine gene expression.

Advances in molecular and cellular biology have identified the cellular mediators that regulate many disease processes and have facilitated the development of new therapeutic agents that control these events. However, the size, complexity, and cellular inaccessibility of these therapeutic agents make their cellular delivery difficult. Here, we describe an efficient cellular delivery system that exploits the membrane-translocating ability of signal peptides to import functional peptides into cells. Molecular conjugates consisting of the signal import peptide (IP) and nuclear localization sequence (NLS) of the transcription factor NF-kappaB were synthesized. Electrophoretic mobility shift and enzyme-linked immunosorbent assays were used to assess the inhibitory effects of these synthetic peptides on agonist-induced NF-kappaB nuclear translocation and transcriptional activation. Our results indicated that the peptides were effective in inhibiting both the nuclear translocation and transcriptional activation of NF-kappaB. However, their effects required the presence of the IP moiety for efficient cellular entry of the NLS. Structural analysis of IP showed that the hydrophobic domain, and to a lesser extent the N-terminal domain, was responsible for the membrane translocating activity of IP.

Amino Acid Sequence↗

PubMed2000

Synthesis and characteristics of the human serum albumin-triazine chiral stationary phase.

Human serum albumin (HSA) was successfully bonded to silica with s-triazine as activator. The coupling reaction by this method was rapid and effective. The triazine-activated silica is relatively stable and can be installed for at least 1 month without obvious loss of reactivity when stored below 30 degrees C, pH below 7. It was observed that the amount of bound HSA reached 120 mg/g silica calculated from the UV absorbance difference of the HSA solution. d, l-tryptophan was selected as the probe solute to characterize the properties of HSA bonded s-triazine chiral stationary phase, and separation factor of 9.4 was obtained for d,l-tryptophan. Furthermore, the amount of effective HSA on silica was measured by high-performance frontal analysis, and only 16.8 mg/g silica was responsible for the resolution of d,l-tryptophan. These results indicate that the amount of both the bound and effective HSA on silica with triazine as activator was much higher than those by the Schiff base coupling method. Different kinds of enantiomers were resolved successfully on the aminopropylsilica-bonded HSA s-triazine chiral stationary phase.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2000

Increased protein loss during peritonitis associated with peritoneal dialysis is neutrophil dependent.

BACKGROUND: Peritonitis in peritoneal dialysis patients is accompanied by an enhanced migration of neutrophils (PMNs) and increased protein loss into the peritoneal cavity; however, the role of PMNs in governing increased protein loss during peritonitis associated with peritoneal dialysis is unknown. METHODS: We determined the importance of PMNs in governing changes in peritoneal permeability to protein in New Zealand White rabbits in which acute peritonitis was induced by adding 4 x 106 colony-forming units of Escherichia coli to 35 mL/kg of 0.9% saline dialysate. The total leukocyte and PMN migration into the peritoneal cavity was assessed by differential cell counts in the dialysate, and peritoneal permeability to protein was evaluated by calculating the dialysate to plasma concentration ratio for total protein as a function of time during a six- or eight-hour dwell. In series 1 experiments, leukocytes were depleted from the rabbit circulation by an intravenous injection of mustine (1.2 mg/kg) three days before the experiment; in series 2 experiments, integrin-dependent PMN migration into the peritoneal cavity was inhibited by an intravenous injection of monoclonal antibody (mAb) 60.3 (2 mg/kg) directed against the integrin CD18 on leukocytes five minutes before the experiment. RESULTS: In series 1 experiments, mustine decreased circulating leukocytes by 82 +/- 5% (mean +/- SEM) and circulating PMNs by 93 +/- 3%. Total leukocyte and PMN migration into the peritoneal cavity and peritoneal permeability to protein were decreased in mustine-treated rabbits after exposure to E. coli in the dialysate to levels similar to those found in rabbits without bacterial peritonitis. In series 2 experiments, an intravenous injection of anti-CD18 antibody also abrogated both the enhanced PMN migration into the peritoneal cavity and the increased peritoneal permeability to protein after exposure to E. coli in the dialysate. CONCLUSIONS: PMN migration into the peritoneal cavity is integrin dependent. Increased protein loss during acute, gram-negative bacterial peritonitis in a rabbit model of peritoneal dialysis is PMN dependent.

Acute Disease↗

PubMed2000

[Study on a downstream signal molecule of human CASK/LIN-2].

OBJECTIVE: To elucidate the function of human CASK/LIN-2, a novel member of membrane-associated guanylate kinase homologs family (MAGUK), by using the yeast two-hybrid system(LexA) to screen the protein interacting with the guanylate kinase-like domain(GK) of hCASK and identify possible protein that might involve downstream signal transduction of hCASK. METHODS: PCR strategy was used to amplify GK domain cDNA fragment of hCASK. The DNA was subcloned into pLexA to construct bait vector pLexA-GK. The pLexA-GK was transformed into yeast host strain EGY48; through testing the bait protein and a repression assay, it was demonstrated that the bait protein did not have transcription activation for leu and lacZ reporter genes, however it could enter nucleus, bind LexA operator. Human fetus brain cDNA library plasmids were transformed into EGY48 containing pLexA-GK and p8op-lacZ, and screened on plates of Gal/Raf his- trp- ura- leu- and Gal/Raf his- trp- ura-X-gal. The clones with galactose dependent leu+ and lacZ+ were isolated; their library plasmids were rescued by means of transforming E.coli KC8. These library plasmids were transformed into the yeast again to re-screen. The remaining positive clones were analyzed by PCR and restriction endonuclease. Finally two kinds of target DNA fragments were obtained. RESULTS: The specificity testing indicated that the two target proteins could specially bind GK domain of hCASK. After DNA sequencing and BLASTn analysis on NCBI, it was shown that the two target DNA fragments, 732 and 683 bp, had high sequence similarity with human inhibitors of differentiation 1(Id1) mRNA, with identities of 97%(630/645) and 98%(656/666), respectively. CONCLUSION: GK domain of hCASK could specially interact with Id1 in yeast. Id1 might be a downstream signal molecule of hCASK, which might involve in regulation of cell differentiation.

Base Sequence↗

PubMed2000

Modified sternal elevation for children with pectus excavatum.

OBJECTIVE: To describe our experience in the treatment of pectus excavatum (PE) using a modified sternal elevation procedure. METHODS: From Oct. 1986 to Dec. 1997, 171 patients with PE were admitted to the Department of Pediatric Surgery of the First Hospital of West China University of Medical Sciences. All patients were diagnosed through a history and physical examination. Cardiopulmonary function was assessed by M-mode echocardiography and instrument of pulmonary function in 40 patients before and 4.2 years after surgery which was performed between 1989 and 1994. We performed the following three procedures in the sternal elevation: (1) forming the metal strut in a "arch" shape, (2) suturing the perichondrium into a "pipe" shape, and (3) encouraging patients to do chest expansion exercise after operation. All patients were followed up for 1 to 12 years. RESULTS: The normal contour of the costal cage was enlarged in all but one patient. Exercise tolerance was improved, and cardiac function recovered to the same level as in healthy children, while pulmonary function recovered very slowly after surgery. CONCLUSION: The normal appearance of chest wall can be recovered and normal cardiopulmonary function can be restored by the modified sternal elevation procedure in children with PE.

Adolescent↗

PubMed2000

[Microsurgical treatment of large or giant aneurysms in anterior circle of Willis].

OBJECTIVE: To improve the operative results in large or giant aneurysms of the anterior circle Willis. METHODS: Retrospective analysis was performed on 28 patients with large or giant aneurysms of the anterior circle Willis after operation. Three-D CT angiography was used to detect and delineate aneurysm preoperatively. Improved operative technique included cranial base approach, temporary artery occlusion, intra-aneurysm decompression, obliteration of aneurysm with multiple clips, stepwise coagulation clipping and resection of aneurysms. RESULTS: Good results were noted in 24 patients (85.7%), fair in 2, and poor in 1. One patient died, but no patient with Hunt and Hess 0-III grade died. CONCLUSIONS: Three-D CT angiography is useful in delineating the shape, size, neck of aneurysms, and their relation to near arteries and to cranial base structures. These are helpful to improve operative results of large or giant aneurysms of the anterior circle of Willis.

Adult↗