Biomedical subjects

W Qi

Publications and source records attributed to W Qi.

At least 55 records · Page 3Linked to original sources

PubMed2000

[Dynamic changes of serum pro-inflammatory cytokines and anti-inflammatory cytokines in patients with acute infection and the effect of Chinese herbal medicine intervention].

OBJECTIVE: To study the dynamic changes of serum pro-inflammatory cytokines and anti-inflammatory cytokines in patients with acute infection and to explore the effect of 912 compound, a Chinese herbal preparation for intervention. METHODS: Forty patients with acute infection were randomly divided into 2 groups, 20 in the 912 group and 20 in the control group, and the levels of plasma endotoxin (lipopolysaccharide, LPS), serum pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) and anti-inflammatory cytokines, including soluble TNF-RI, IL-4 and IL-10 were measured before and after treatment by using limulus reagent stroma azo-colored quantitative method and enzyme-linked immunosorbent assay (ELISA). RESULTS: The level of LPS increased at the early stage of acute infection, the levels of pro- and anti-inflammatory cytokines were all elevated in various degrees, particularly obvious in IL-6, sTNF-RI, IL-4 and IL-10 and the elevations of the two were basically parallel. The TNF alpha, IL-6 and sTNF-RI were positively related with APACHE III scoring. The levels of LPS and inflammatory cytokines reduced to a different extent in accord with the improvement of condition after treatment, the levels of LPS, TNF alpha, IL-6 and IL-10 lowered more significantly in the 912 group than those in the control group (P < 0.05). CONCLUSIONS: LPS, pro-inflammatory and anti-inflammatory cytokines play important roles in the acute infection process, they were important indexes for evaluating severity of infectious diseases. The Chinese herbal preparation 912 compound could reduce the blood levels of LPS, TNF alpha, IL-6, IL-10 and prevent the decrease of sTNF-RI so as to promote the recovery of patients.

Adult↗

PubMed2000

[A procedure for developing selective isolation of Pseudonocardiacetes from soil samples].

Pseudonocardiacetes are a group of rare-actinomyces with type IV cell walls and without mycolic acids. Five different selective isolation media S1, S2, S3, S4 and S5 were devised and practiced to improve their selective isolation efficiency. The media were detected by 33 type strains of Pseudonocardiaceae, 4 strains of Saccharothrix and 15 type strains of Streptomyces cultured on them. Soil samples were examined on media S1 ad S2 compared with glucose-asparagine agar. It shows that media S1 and S2 are effective for growth and isolation of Amycolata, Pseudonocardia, Saccharomonospora and other genera of Pseudonocardiaceae.

Actinomycetales↗

PubMed1999

Inhibitory effects of melatonin on ferric nitrilotriacetate-induced lipid peroxidation and oxidative DNA damage in the rat kidney.

Ferric nitrilotriacetate (Fe-NTA) is a known complete renal carcinogen which induces lipid peroxidation and oxidative DNA damage in rat kidney. In this study, the in vivo and in vitro effects of melatonin on Fe-NTA-induced lipid and oxidative DNA damage were determined. The levels of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) were assayed as an index of lipid peroxidation and the levels of 8-hydroxydeoxyguanosine (8-OH-dG) as an endpoint of oxidative DNA damage. In in vitro studies, the increased levels of MDA and 4-HDA induced by Fe-NTA were observed to be dose-dependent and time-dependent. The increase in lipid peroxidation was inhibited by melatonin in a concentration-dependent manner. When Fe-NTA(15 mg Fe/kg body weight) was intraperitoneally injected into rats, the levels of MDA + 4-HDA and 8-OH-dG in the rat kidney were increased 1 h after its administration as compared to levels of these constituents in the control group. Pretreatment with melatonin (25 mg/kg or 50 mg/kg) 30 min before the Fe-NTA injection resulted in a significant reduction in the levels of lipid peroxidation and 8-OH-dG induced by Fe-NTA in the rat kidney. These results are consistent with the conclusion that the toxicity of Fe-NTA is due to the generation of reactive oxygen species and that melatonin's protective effects relate to its direct radical scavenging ability and due to other antioxidative processes induced by the indole.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed1999

High physiological levels of melatonin in the bile of mammals.

Bile is an important physiological bodily fluid which functions in the regulation of cholesterol metabolism, promotes the absorption of lipid and fat-soluble vitamins by the gut and serves in the excretion of toxic substances from the liver. Conversely, due to autooxidative processes bile is highly toxic to the hepatocyte and gastrointestinal epithelium. In this investigation, extremely high day time physiological levels of the endogenous antioxidant, melatonin, were measured in the bile of several mammals including rat, guinea pig, rabbit, pig, monkey and humans. Melatonin concentrations in the bile samples ranged from 2,000 to 11,000 pg/ml when measured by radioimmunoassay (RIA). These melatonin levels in bile are 2 to 3 orders of magnitude higher than those in day time serum. The presence of melatonin in bile was confirmed by HPLC with an electrochemical detector. This method, like the RIA, also documented very high levels of melatonin in bile. The presence of high levels of melatonin in bile may be essential to prevent oxidative damage to biliary and small intestinal epithelium induced by bile acids and oxidized cholesterol derivatives.

Adult↗

PubMed1999

Augmentation of indices of oxidative damage in life-long melatonin-deficient rats.

The chief pineal secretory product, melatonin, is an efficient free radical scavenger and antioxidant. The current study tested whether the life-long reduction of endogenous melatonin levels due to pinealectomy would influence the accumulation of oxidatively damaged products as the animals aged. Rats were either pinealectomized or sham operated when they were 2-months-old. At 25 months of age these animals were killed along with 2-month-old controls. Aging in the pineal-intact animals was associated with increased levels of lipid peroxidation products (malondialdehyde and 4-hydroxyalkenals in the lung, kidney and skin), rises in an oxidatively damaged DNA product (8-hydroxy-deoxyguanosine in liver, kidney and pancreas), and in the levels of protein carbonyls (in the liver). Likewise, advanced age was associated with a significant decrease in membrane fluidity (increased membrane rigidity) of hepatic microsomes in pineal-intact rats. For all of these parameters and in a number of organs, pinealectomy caused further increases in the indices of oxidative damage. Consistent with previous suggestions, the implications of these findings is that aging is associated with the augmented accumulation of oxidatively damaged macromolecules and that these increases are exaggerated when a relative melatonin deficiency is induced by pinealectomy. The findings are consistent with the idea that the accelerated accumulation of oxidatively damaged products after pinealectomy was due to reduction in melatonin since it functions as a free radical scavenger and antioxidant. On the other hand, other pineal secretory products that were reduced as a consequence of pineal removal may have also been responsible for some of the observed changes.

Aging↗

PubMed1999

Intermittent high glucose enhances cell growth and collagen synthesis in cultured human tubulointerstitial cells.

AIMS/HYPOTHESIS: We investigated the effects of constant and intermittently increased glucose concentrations on human proximal tubule cells and cortical fibroblasts in primary culture. METHODS: Cells were grown to confluence and then exposed for 4 days to 6.1 mmol/l D-glucose (normal), 25 mmol/l D-glucose (high), or 6.1 mmol/l alternating with 25 mmol/l D-glucose on a daily basis. RESULTS: In proximal tubular cells, exposure to high glucose caused an 11 % increase in thymidine uptake (p < 0.05), a 230 % increase in secretion of transforming growth factor beta 1 (TGF-beta1; p < 0.05) and a 393 % increase in platelet derived growth factor. Intermittent exposure to high glucose caused thymidine uptake to further increase by 42 % (p < 0.01) and TGF-beta1 secretion by 352 % (p < 0.01) but no additional increase in platelet-derived growth factor secretion was observed. Cellular protein content increased by 27 % (p < 0.05) and collagen synthesis by 29 % (p < 0.05), changes that were not observed in cells constantly exposed to high glucose. In cortical fibroblasts constant exposure to high glucose caused a 35 % increase in thymidine uptake (p < 0.01). Intermittently high glucose increased thymidine incorporation a further 58 % (p < 0.001), collagen synthesis by 65 % (p < 0.01) and insulin-like growth factor binding protein 3 secretion by 216 % (p < 0.01). CONCLUSION/INTERPRETATION: In cultured human tubulointerstitial cells, increased glucose concentrations change cell growth, collagen synthesis and cytokine secretion. These effects are enhanced following intermittent exposure to high glucose, indicating that short lived excursions in glycaemic control have important pathological effects on the human tubulointerstitium.

Aged↗

PubMed1999

Melatonin reduces lipid peroxidation and tissue edema in cerulein-induced acute pancreatitis in rats.

Since oxygen free radicals and lipid peroxidation have been implicated in the pathogenesis of an early stage of acute pancreatitis, we examined whether melatonin, a recently discovered free-radical scavenger, could attenuate pancreatic injury in Sprague-Dawley rats with cerulein-induced pancreatitis. Acute pancreatitis was induced by four intraperitoneal injections of cerulein (50 microg/kg body wt) given at 1-hr intervals. Thirty minutes after the last cerulein injection, the rats were killed and the degree of pancreatic edema, the level of lipid peroxidation in the pancreas, and serum amylase activity were increased significantly. Pretreatment with melatonin (10 or 50 mg/kg body wt) 30 min before each cerulein injection resulted in a significant reduction in pancreatic edema and the levels of lipid peroxidation. Serum amylase activity, however, was not significantly influenced by either dose of melatonin. Moreover, we found that cerulein administration was associated with stomach edema as well as high levels of lipid peroxidation in the stomach and small intestine, which were also reduced by melatonin. Melatonin's protective effects in cerulein-treated rats presumably relate to its radical scavenging ability and to other antioxidative processes induced by melatonin.

Acute Disease↗

PubMed1999

[Clinical observation on 51 patients of acute myocardial infarction treated with thrombolytic therapy combined with Chinese herbal medicine].

OBJECTIVE: To assess the efficacy of thrombolytic therapy combined with Chinese herbal medicine (CHM) in treating acute myocardial infarction (AMI). METHODS: One hundred and one cases of AMI were divided randomly into two groups. The treated group treated with thrombolytic therapy combined with CHM and the control group treated with thrombolytic therapy alone. The criteria of patency of coronary artery were conducted according to the referential standard of thrombolytic therapy in treating AMI introduced by Chinese Angiocardiopathy Medical Journal, 1991. RESULTS: The patency rate of coronary artery of the two groups were 68.63% and 56.00%, the four-week mortality 3.92% and 10.00%, hemorrhage occurrence 1.96% and 10.00%, congestive heart failure occurrence 5.88% and 16.00%, severe arrhythmia occurrence 11.76% and 22.00%, and the shock occurrence 3.92% and 8.00% respectively. The difference between the two groups was significant, P < 0.01, P < 0.05. CONCLUSION: The effect of the treated group was better and the complication occurrence of the treated group was lower than those of the control group.

Adult↗

PubMed1999

[The thumb reconstruction by transferring the injured index finger with pedicles].

OBJECTIVE: In order to inquire the methods of thumb reconstruction by transferring the index finger with incomplete conditions of nerve or blood vessels. METHODS: From April 1987 to October 1997, 6 cases were treated by 3 kinds of operative methods according to the damage type of thumb and complications injures of the rest of hand: 1. transferring the index finger with pedicle without proximal phalanx, 2. transferring the index finger with palmar nerve and blood vessels, and dorsal skin pedicle, 3. transferring the index finger with compound pedicle. RESULTS: All 6 cases of thumb reconstruction were successful. Followed up 6 months to 2 years, the pinching and gribing functions in 6 cases were completely recovered, and the sensation were partly recovered. CONCLUSION: The operative method of thumb reconstruction had following advantages: Simple operation, high survival rate and certain function recovery. It can enlarge the indications of thumb reconstruction.

Adult↗

PubMed1999

[Simultaneous analysis of histamine and noradrenaline in human plasma by high performance liquid chromatography/electrochemical detection].

This paper reports a reversed-phase high performance liquid chromatographic method for the simultaneous separation and determination of histamine(Hist) and noradrenaline(NA) in human plasma by means of pre-column derivatization of Hist and NA with OPA in the presence of 2-mercaptoethanol. The analysis was carried out with Partisil ODS column, V[sodium acetate buffer solution(pH 4.90)]:V(acetonitrile) = 7:3 as mobile phase and 3-methylhistamine as internal standard. The detector potential was +0.7 V for both compounds to keep minimum background noise. A linear relationship between the electrochemical signal and the compound mass concentrations was obtained. The minimum detectable limit was 15 ng/L (S/N = 3). An example of application of the method to the determination of Hist and NA in human plasma is presented.

Chromatography, High Pressure Liquid↗

PubMed1999

[Taxonomic study of four isolates of Saccharomonospora].

Four strains, 19.1, 22.1, 202, and 212, were isolated from the soil samples of Guangxi province in China. Basing on their morphological and cell chemical characteristics(cell wall type IV, sugar type A, without mycolic acids), they were circled into the genus of Saccharomonospora. They were studied with 7 type strains of the 5 currently recognized species in the genus. The results of Ribotyping suggest that strain 19.1 blongs to the species of S. viridis, strain 202 is a member of S. caesia, strain 22.1 and strain 212 are the same species, which is different to the 5 currently known species. It is closely related to S. viridis. However, the further classification of these two strains at species level needs 16S rRNA sequence date.

Actinomycetales↗

PubMed1999

Defense mechanisms of urinary bladder: studies on antimicrobial polypeptides from bladder mucosa.

The acid-soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash-out materials from rats, rabbits, pigs, and humans manifested strong bactericidal activity against E. coli in vitro. The ultrafiltrate of the human material, which contained two major peptides with apparent molecular masses of 6.7 kD and 8.5 kD, respectively, showed potent bactericidal activity against E. coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus sanguis. Three antibacterial polypeptides (PiBPs) were purified from the porcine material. The molecular masses of PiBP-5, PiBP-11 and PiBP-25 were 5773.3 Da, 11127.8 Da and 25073 Da, respectively. PiBP-5 was unusually rich in glycine, serine and threonine residues (20.0, 16.3 and 10.4 mol%, respectively), and N-terminal amino acid sequencing revealed that PiBP-5 was homologous (83.3% identity in an 18 residue overlay) to the "tail" of human cytokeratin-7. Although the amino acid compositions of PiBP-11 and PiBP-25 were established, both had blocked N-termini and primary sequence data were not obtained. These results provided evidence indicating that the presence of peptides in the bladder mucosa could enable it to kill adherent bacteria.

Amino Acid Sequence↗

PubMed1999

[Determination of 14 rare earth impurities in Y2O3 by petroleum sulfoxide extraction chromatography].

Petroleum sulfoxide-NH4SCN extraction chromatography was developed for the separation of Y from other rare earth elements. Some chromatographic parameters were chosen and separation factors between Y and other rare earth elements were determined. A column of resin coated with petroleum sulfoxide was used. The Y in the sample was eluted with NH4SCN, then titrated with EDTA. The recovery was 67%-120% and relative standard deviation +/- 4.0%-19.4%. This method can be applied to the determination of trace amounts of rare earth impurities in Y2O3 with a purity of 99.9999%-99.99999%.

English Abstract↗

PubMed1999

[Determination of rare-earth impurities in ultra-highly pure Er2O3 and Ho2O3 by [HEH(HEP)] extraction chromatography-atomic emission spectrometry].

This article applied [HEH(HEP)] (2-ethyhexyldrogen-2-ethylhexyl phosphonate) extraction chromatography to separate 14 rare earth impurities from ultra-highly pure Er2O3 and Ho2O3, and then the impurities were determined by atomic emission spectrometry. The average percentage recovery for each element is in the range of 70%-140%. The relative standard deviations of the determination are +/- 3.3%-2.2%. This method can be applied to the determination of the trace amounts of rare eath impurities in Er2O3 and Ho2O3 with a purity of 99.9999%-99.99999%.

English Abstract↗

PubMed1998

Melatonin protects hippocampal neurons in vivo against kainic acid-induced damage in mice.

In this investigation, 40 mg/kg of the excitatory neurotoxin kainic acid (KA) was subcutaneously administered to CD2-F1 mice. In this mouse strain morphological damage induced by KA in the hippocampus was markedly concentrated in the CA3 pyramidal neurons. Neuronal injury was accompanied by several pathological neurobehavioral activities including arching of tail, tremors and seizures, and by certain biochemical changes, i.e., increased lipid peroxidation products (LPO) in the brain. When melatonin was injected intraperitoneally at a single dose of 5 mg/kg 10 min before KA administration, it significantly reduced these pathological neurobehavioral changes and almost completely attenuated the increase in LPO and morphological damage induced by KA. The neuroprotective effect of melatonin against KA-induced brain damage in mice is believed to be in part related to its oxygen radical scavenging properties as well as its antiepileptic and GABA receptor regulatory actions. Considering melatonin's relative lack of toxicity and ability to enter the brain, these results along with previous evidence suggest that melatonin, which is a natural substance, may be useful in combating free radical-induced neuronal injury in acute situations such as stroke and brain trauma as well as neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease that have free radicals as causative factors.

Animals↗

PubMed1998

Expression of a fusion protein of scFv-biotin mimetic peptide for immunoassay.

We constructed two fusion proteins of scFv linked to biotin mimetic sequence (BMS) via different linkers, and expressed them in the Pichia pastoris expression/secretion system. We found that both bi-functional scFv proteins exhibited their intrinsic binding activities to antigen CA125 determined in competitive radioimmunoassay experiments, but the fusion protein with a spacer between the scFv and BMS (scFv-spacer-BMS) showed higher binding activity of streptavidin than the one with c-Myc peptide as a linker.

Antibodies, Bispecific↗

PubMed1998

2-Nitropropane-induced lipid peroxidation: antitoxic effects of melatonin.

The degree of lipid peroxidation (LPO) as indicated by the levels of thiobarbituric acid reactive substances, malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA), and the activity of sorbitol dehydrogenase (SDH) in serum as parameters of hepatotoxicity were studied in rats treated with a single intraperitoneal (i.p.) injection of the hepatocarcinogen 2-nitropropane (2-NP). Since melatonin, the main secretory product of the pineal gland, has been shown to protect against a number of toxic agents, it was given 30 min before 2-NP to test its protective effect against 2-NP toxicity. Significant increases in LPO in liver (P<0.0001), lung (P<0.05) and kidney (P<0.0001) were observed 24 h after 4 mmol/kg 2-NP while serum SDH activity was increased 470-fold. All parameters showed time (0, 4, 8, 24 h) and dose (0, 1, 2, 3, 4 mmol/kg) dependency. The induction of LPO by 2-NP was significantly reduced in lung and kidney when melatonin (2.5, 5 or 10 mg/kg) was given prior to 2-NP administration. The elevation in serum SDH caused by 2-NP was also reduced when melatonin was given. These findings show that 2-NP induces LPO and that pharmacological levels of melatonin can reduce the toxicity of this hepatocarcinogen.

Aldehydes↗

PubMed1998

Regulation of alphaIIb beta3 function in human B lymphocytes.

We studied the function of the platelet integrin alphaIIb beta3 using a B lymphocyte model in which alphaIIb beta3 can be induced to interact with fibrinogen using phorbol myristate acetate (PMA). To determine whether a G protein-coupled receptor could also activate alphaIIb beta3 in lymphocytes, we coexpressed the human formyl peptide receptor (fPR) and alphaIIb beta3, finding that the fPR agonist formyl Met-Leu-Phe (fMLP)-stimulated lymphocyte adherence to immobilized fibrinogen and binding of soluble fibrinogen to the lymphocyte surface. The response to fMLP, but not PMA, was abrogated by pertussis toxin, indicating that the fPR was coupled to the G-protein Galphai, whereas the protein kinase C inhibitor bisindolylmaleimide I inhibited the response to both fMLP and PMA, indicating that signaling from the fPR included protein kinase C. On the other hand, the tyrosine kinase inhibitor genistein, the Syk inhibitor piceatannol, and the RhoA inhibitor C3 exoenzyme had no effect, implying that neither tyrosine phosphorylation nor the GTPase RhoA were involved. Furthermore, whereas micromolar concentrations of cytochalasin D inhibited the PMA-stimulated interaction of alphaIIb beta3 with fibrinogen, nanomolar concentrations actually induced fibrinogen binding to unstimulated cells. Our studies demonstrate that alphaIIb beta3 expressed in B lymphocytes can be activated by a physiologic agonist and outline an activating pathway that includes Galphai, protein kinase C, and the actin cytoskeleton.

B-Lymphocytes↗