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OBJECTIVE： To e stablish modified aqueous two-phase extraction （ATPE） system of polyphenols from Archidendron clypearia. METHODS ：Taking the polyphenol content ，extraction efficiency and partition coefficient of A. clypearia as indexes ，the solid-liquid ratio ，ethanol mass fraction and ultrasonic time of ATPE system were selected by single factor tests . The aqueous two-phase extracts from different polar parts of A. clypearia was prepared. The modifier was selected by taking polyphenol content and antioxidant activity [IC 50 of 1，1-diphenyl-2-trinitrophenylhydrazine （DPPH）， 2，2′-hydrazine bis （3-ethylbenzothiazole-6-sulfonic acid ） diammonium salt （ABTS）] as indicators ，combined with the grey correlation analysis between polyphenols and antioxidant activity. The effects of modified ATPE system with different mass fraction （0-90％）of modifier on the extraction of polyphenols from A. clypearia were investigated and compared with traditional extraction technology （ultrasonic extraction and heating reflux extraction ）. RESULTS ：The optimal ATPE system included solid-liquid ratio of 1 ∶ 45， ethanol mass fraction of 40％，（NH4）2SO4 mass fraction of 11％，ultrasonic extraction time of 20 min，at room temperature. In 3 validation tests ，polyphenol content ，extraction efficiency and partition coefficient were （28.35±1.01）％（RSD＝3.56％，n＝3）， （98.87±0.19）％（RSD＝0.19％，n＝3）and 13.25±0.71（RSD＝5.39％，n＝3），respectively. The modifier was ethyl acetate. When the mass fraction of ethyl acetate in the ethyl acetate-ethanol mixed solvent was 70％，there was no significant difference in the content and anti-oxidant activity of polyphenols from A. clypearia of modified ATPE （P＞0.05）. The yield and transfer rate of it were si gnificantly higher than those of ultrasonic extraction and heating reflux extraction （P＜0.05）. CONCLUSIONS ：The modified ATPE system with better extraction yield and transfer rate than the traditional extraction technology is successfully established，which can extract polyphenols from A. clypearia 1048214903@qq.com in one step.
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Objective To investigate the prevalence of plasmid-mediated quinolone resistance(PMQR) in Proteus mirabilis clinical isolated from urine. Methods Antimicrobial susceptibility test was performed using the microdilution method.And PMQR gene qnrA,qnrB,qnrC,qnrD,qnrS,aac(6′)-Ib-cr,qepA were amplified by PCR,then the PCR positive products were sequenced to identify their genotypes. Results In 41 strains of Proteus mirabilis from urine,the resistant rates to ciprofloxacin and levofloxacin were 41.5% and 29.3%,respec-tively.Among all clinical isolates,qnrA1 gene was detected in 2 strains,qnrB2 gene in 3 strains.PMQR gene qn-rB,qnrC,qnrD,qnrS,aac(6')-Ib-cr and qepA were not detected in all strains.Conclusions Clinical isolates of Proteus mirabilis from urine carry PMQR genes.The prevalent principal genotypes are qnrA1 and qnrB2 in these iso-lates.They are related to low levels resistance toquinolone.
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AIM:To investigate the effects of thalidomide ( THD) on the activation of connective tissue growth factor ( CTGF) gene promoter induced by transforming growth factor β1 ( TGF-β1 ) in human embryonic lung fibroblasts ( HELF) .METHODS:DNA sequence of CTGF gene promoter was cloned into luciferase reporter gene vector to construct the recombinant eukaryotic expression vector pGL 3-CTGFP, and the recombinant vector was transfected into HELF cell line.The effects of TGF-β1 and THD on the activation of CTGF gene promoter were detected by dual-luciferase analysis . RESULTS:TGF-β1 increased the reporter gene activity dose-dependently (P<0.05), with a plateau at 5 μg/L being 2.16 folds as high as the control .TGF-β1-induced increase in the reporter gene activity was also time-dependent ( P<0.05).After exposure to TGF-β1(5 μg/L), the level of luciferase activity reached its peak at 12 h and was 2.52 folds as high as the control .THD significantly inhibited TGF-β1-induced increase in the reporter gene activity in a dose-dependent manner , but its basal activity was not changed .CONCLUSION: TGF-β1 stimulates the transcriptional activity of CTGF gene promoter in HELF cells in a dose-and time-dependent manner , while THD may inhibit the effects dose-dependently .
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The present study was undertaken to investigate the effect of human PMNs on the production of TNF-α by the human peripheral blood mononuclear cells (PBMCs) and to elucidate its tentative mechanism. Human PMNs and PBMCs were isolated from the venous blood of healthy donors by dextran sedimentation and density gradient centrifugation. In the presence of lipopolysaccharide (LPS), PMNs and PBMCs were cocultured at the ratio of 2:1 for 20 h and the concentration of TNF-α in the supernatant was measured by enzyme-linked immunosorbent assay. The binding rate of monocytes with the fluorescein isothiocyanate-labeled LPS (FITC-LPS) and the mean surface fluorescence intensity of monocytes were analyzed by flow cytometry. Results showed that PMNs were capable of inhibiting the TNF-α release from PBMCs (P＜0.05). PMNs suppressed the TNF-α release from PBMCs by 45% on average when PMNs and PBMCs cocultured at the ratio of 2:1. Paraformaldehyde-fixed PMNs still demonstrated the same inhibition (P＜0.05)，which proved that the inhibition was dependent on cell-to-cell contact and suggested that effector molecules responsible for this effect existed on the cell surface of PMNs. In the presence of PMNs, the binding rate of monocytes with the FITC-LPS and the mean surface fluorescence intensity of monocytes were not affected compared with PBMCs alone (P＞0.05). As incubation time was prolonged, the binding of FITC-LPS to monocytes increased (P＜0.05). Thus PMNs did not block the binding of LPS with monocytes. It was concluded that PMNs suppressed the TNF-α release from PBMCs via cell-to-cell interaction. In a cell-contact dependent manner, PMNs might interfere with the signal transduction pathway through which LPS activated PBMCs, thus attenuating the response of PBMCs to LPS and downregulating the TNF-α release.
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Abstract］ AIM and METHODS:The recent work from our laboratory showed that ventral septal area (VSA) played a negative-regulatory central role in thermoregulation during endogenous pyrogen-induced fever. In order to further investigate the role of VSA in the antipyretic mechanism, we observed the effects of electrical stimulation of VSA on firing characteristics of thermosensitive neurons in preoptic anterior hypothalamus (POAH) by using extracellular microelectrode technique on 32 New Zealand white rabbits treated with interleukin-1 β (IL-1β) intracerebroventriculary (ICV). RESULTS:(1)Injection of IL-1β decreased discharging rate of warm-sensitive neurons in POAH. Electrical stimulation of VSA remarkably decreased thermosensitive coefficient of warm-sensitive neurons. (2)Injection of IL-1β caused increase in discharging rate of cold-sensitive neurons in POAH. Electrical stimulation of VSA remarkably increased thermosensitive coefficient of cold-sensitive neurons. CONCLUSTION:VSA may have an antipyretic effect through affecting the firing characteristics of thermosensitive neurons in POAH during IL-1β-induced fever.
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AIM and METHODS:To investigate the effect of electrical stimulation of VSA on the firing of thermosensitive neurons in preoptic anterior hypothalamus (POAH), the firing rate of thermosensitive neurons in POAH of 20 New Zealand white rabbits was recorded by using extracellular microelectrode techinque. RESULTS:(1)Electrical stimulation of ventral septal area (VSA) caused a significant increase in firing rate of warm-sensitive neurons in the preoptic area of the anterior hypothalamus(POAH).(2) The firing rate of cold-sensitive neurons was decreased remarkably in the POAH by electrical stimulation of VSA. CONCLUSION:VSA may play a controlling role in the thermoregulation through altering the firing rate of thermosensitive neurons in the POAH.
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AIM: The present study was undertaken to explore the effects of ?-MSH on partial biological activities of LPS. METHODS:Colorimetric method was used for the measurement of hydrogen peroxide(H_2O_2) production in mouse peritoneal macrophages, the apoptosis of polymorphonuclear leukocytes(PMNs) and the binding of LPS to monocytes were studied with flow cytometry. RESULTS: It was found that LPS strongly stimulated macrophages to release H_2O_2. When macrophages were cultured with ?-MSH in the presence of LPS, the H_2O_2 release was markedly suppressed (P0.05). In the presence of LPS, however, ?-MSH significantly promoted the apoptosis of PMNs (P
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AIM: To explore effects of glycine and polymyxin B mixture (Gly/PMB) on endotoxin-induced acute phase response in vivo . METHODS: Model of acute phase response was reconstructed by endotoxin (ET) in rabbits. Specimens of blood were collected at 1 hour after the highest body temperature. Leukocyte count, serum C-reactive protein and trace element were also detected. RESULTS: Pretreatment of half-dose Gly/PMB significantly inhibited acute phase response induced by ET ( P 0.05). CONCLUSION: These results suggested that glycine enhanced the inhibitory effect of polymyxin B on ET-induced acute phase response. The advantage of glycine and polymyxin B mixture was decreasing dosage and side effects of polymyxin B. [
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AIM: To investigate the effect of granulocyte colony stimulating factor (G-CSF) on arabinosyl cytosine (Ara-C)-induced apoptosis in HL-60 leukemia cells. METHODS: The proliferation of HL-60 leukemia cell was observed by hemopoietic cell culture. Apoptosis was measured by the morphology of apoptosis cell , the quantitation of DNA fragmentation with the diphenylamine reaction. The change in drug sensitivity was measured by “MTT”. RESULTS: G-CSF could stimulate the proliferation of HL-60 leukemia cell and colonies of cell increased to 76.5?18.0, compared to the control group (46.5?13.5. P
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AIM: To investigate whether glycine receptor is involved in the protection of glycine against(anoxia/reoxygenation) injury in cardiomyocytes by detecting oxygen free radical metabolism,apoptosis and intracellular calcium overload.METHODS: The neonatal rat cardiomyocytes were cultured and exposed to anoxia and reoxygenation((A/R)) in the presence of glycine receptor antagonist,glycine or in free chloride buffer.The superoxide dismutase(SOD) activity,the contents of malondialdehyde(MDA) and nitric oxide(NO),the intracellular free calcium concentration and the apoptotic rate in the cardiomyocytes were determined.RESULTS: SOD activity and NO content in cardiomyocytes were lower,but MDA content,intracellular free calcium concentration and apoptotic rate in cardiomyocytes were higher in A/R group than those in control.Pretreatment with glycine inhibited the above changes caused by A/R,which was reversed by strychnine treatment and in the free chloride medium.CONCLUSIONS: Glycine inhibits free radical production,attenuates calcium overload,decreases apoptotic rate and increases SOD activity and NO release in cardiomyocytes exposed to(A/R).These findings suggest that glycine exerts a protective effect against A/R injury via glycine receptor and glycine protects the neonatal rat cardiomycytes from A/R-induced injury in a chloride-dependent manner.
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AIM: To study the changes of serum levels of thromboxane A_2(TXA_2) and prostacyclin(PGI_2) in cirrhosis patients during liver transplantation.METHODS: Samples were obtained from 24 cirrhosis patients in end at five time points during liver transplantation.TXA_2 and PGI_2 level were measured by radioimmunoassay.Arterial and mixed venous blood samples used for blood gas analysis were taken at the same time.Intrapulmonary shunt(Qs/Qt) was calculated according to the standard formula.The hemodynamics parameters including continuous cardiac output index(CI),HR,mean artery blood pressure(MABP),MPAP,CVP,PAWP,SVRI,PVRI were measured during liver transplantation.RESULTS:(1) MABP decreased significantly in the early stage of anhepatic period and neohepatic period.(2) CVP,MPAP and PAWP decreased significantly during anhepatic period.They increased significantly after graft reperfusion and remain the high level.(3) CI declined significantly during anhepatic period and increased at 10 min postreperfusion of new liver.(4) SVRI and PVRI increased during anhepatic period and were higher than baseline level at 15 min after reperfusion.SVRI was lower than baseline level at 30 min after reperfusion.(5) Compared with the baseline level,6-keto-PGF1? and TXB_2 increased significantly.Compared with the level before vascular cross-clamping,6-keto-PGF1? decreased during neohepatic period and it had significant difference in statistics at the end of operation.CONCLUSION: Serum levels of TXA_2 and PGI_2 significantly change during liver transplantation and may affect the system and pulmonary circulation to some extent.
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AIM: To study the changes of serum levels of nitric oxide (NO) and nitric oxide synthase (NOS) in patients during liver transplantation. METHODS: Samples were obtained from 30 patients in end liver disease at five time points during liver transplantation. NO level and NOS activity were measured by radioimmunoassay and colorimetry, respectively. Arterial and mixed venous blood samples used for blood gas analysis were taken at the same time. Intrapulmonary shunt (Qs/Qt) was calculated according to the standard formula. The hemodynamics parameters including continuous cardic output (CO), HR, MABP, CVP, SVR were measured during liver transplantation. RESULTS: (1) NO_2-/NO_3-level at 10 min before anhepatic period was significantly higher than the baseline level. Compared with NO_2-/NO_3-level at 10 min before anhepatic period, NO_2-/NO_3-level at 30 min after anhepatic period was significantly decreased. NO_2-/NO_3-level at 30 min after neohepatic period was significantly higher than the baseline level and at 30 min after anhepatic period. (2) No significant change of tNOS activity was observed. Compared with the baseline activity of inducible nitric oxide synthase (iNOS), the activity at 10 min before anhepatic period and at 30 min after neohepatic period was significantly increased. The activity at 30 min after neohepatic period was significantly higher than that at 30 min after anhepatic period. (3) MABP decreased significantly when opening the inferior vena cava. CO and CVP decreased in the anhepatic stage and increased in the reperfusion stage. SVR increased during anhepatic stage and decreased significantly during neohepatic period. (4) Qs/Qt decreased significantly during anhepatic stage and increased significantly at 30 min after neohepatic period. CONCLUSIONS: Serum level of NO and NOS activity are significantly changed during liver transplantation. High level of NO may result in low systemic vascular resistance and increasing in intrapulmonary shunt.
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AIM: To investigate the mechanisms by which siduqing, a Chinese medicine, protects against lipopolysaccharide (LPS)-induced acute renal dysfunction. METHODS: Mice were divided randomly into control, LPS, siduqing treatment and siduqing groups, and treated intragastrically with siduqing at a dose of (1 000) g/L (0.2 (mL/10 g) body weight) or distilled water (0.2 (mL/10) g body weight) twice a day for 3 days, LPS (30 mg/kg) or normal saline was injected intraperitoneally on day 3, followed by intragastrical administration with siduqing at a dose of (1 000) g/L (0.2 (mL/10 g) body weight) or distilled water (0.2 (mL/10 g) body weight). Blood was collected for determining urea nitrogen (BUN) and creatinine (Cr) contents, renal tissue for examining superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. In addition, electron microscopy was used to examine the ultrastructure changes in kidney, and RT-PCR was performed to detect renal intercellular adhesion molecule-1 (ICAM-1) mRNA expression. RESULTS: LPS significantly increased serum urea nitrogen (BUN) and creatinine (Cr) contents, and produced an obvious pathological change in renal ultrastructure, which were significantly attenuated by siduqing treatment. Moreover, siduqing treatment increased renal SOD activity, also markedly suppressed an increase in renal MDA production and ICAM-1 mRNA expression induced by LPS. CONCLUSION: These results suggest that siduqing protects against LPS-induced acute renal injury through inhibiting ICAM-1 mRNA expression, enhancing renal SOD activity and attenuating oxidant stress.
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AIM: To investigate effects of Retinervus luffae fructus (RLF) on level of serum lipid and body weight in hyperlipidemia rats. METHODS: Thirty-two male SD rats were randomly divided into four groups: control group (A), hyperlipidemia group (B), hyperlipidemia + RLF group (C), RLF group (D). Both group A and C were fed normal diet every day, while group B and group D fed high fat diet. Meanwhile, group C and D were administered with RLF solution at the dose of 10 mL/kg, respectively for 14 days, while group A and B were administered with drinking water. RESULTS: (1) At the end of experiment, a significant reduction was found in the levels of serum total cholesterol (TC) and triglyceride (TG) of group C animals treated with RLF solution; (2) The levels of serum TC of group D was progressively decreased compared to the level of serum TC at the beginning of experiment; (3) The level of high-density lipoprotein cholesterol (HDL-C) of group C remained unaltered 8d after treatment with RLF solution; (4) The body weight in group C was obviously lower than that in group B. CONCLUSION: RLF had an obvious hypolipidemic effect on hyperlipidemia rats. It can inhibit the decrease in the HDL-C and the increase of body weight in rats. [
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AIM: To study the influence of glycine(GLY) on lipopolysaccharide-binding protein(LBP) mRNA expression induced by LPS. METHODS: The level of LBP mRNA expression in liver tissues of rats was examined by RT-PCR,and the effects of glycine on LBP mRNA expression in liver tissues of rats induced by LPS were investigated. RESULTS: The level of LBP mRNA expression in hepatic tissue of rats in the LPS group was significantly higher than that in the control group( P
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AIM and METHODS: To investigate the functional connection between the preoptic anterior hypothalamus (POAH) and the ventral septal area (VSA) in fever mechanism, the firing rates of thermosensitive neurons in the VSA of 26 New Zealand white rabbits were recorded using extracellular microelectrode technique. RESULTS: The firing rates in both types of thermosensitive neurons in the VSA had no significant changes after intracerebroventricular (icv) injection of artificial cerebrospinal fluid(ACSF). When interleukin-1β (IL-1β) was given (icv), the firing rate of the warm-sensitive neurons was increased significantly and that of the cold-sensitive neurons was decreased remarkably. The effects of IL-1β on the changes of firing rate in thermosensitive neurons of the VSA were reversed by electrical stimulation of the POAH. CONCLUSION: The roles of positive and negative thermoregulatory centers in the interaction between the POAH and VSA are closely linked during endogenous pyrogen induced fever.
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AIM:To investigate the anti-tumor effects of special cytotoxic T lymphocytes(CTLs)activated by dendritic cells(DCs)loaded with antigens and CD40L in vitro.METHODS:Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation from normal human heparinized blood.The adherent cells were cultured with granulocyte-macrophage colony stimulating factor(GM-CSF),interleukin-4(IL-4),alpha tumor necrosis factor(TNF-?),DCs were co-cultured with frozen-thawed antigen of K562 cells and CD40L,then triggered T cells into specific CTLs.RESULTS:Most suspended cells exhibited distinctive morphological features of DCs which expressed CD40 96%,CD86 97%,CD80 77%,CD1a 69%,and gained the powerful capacity to stimulate proliferation of allogenic lymphocytes.Under the effector∶target ratio of 20∶1,CTLs derived from cultures with DCs and frozen-thawed antigen of K562 cells were showed 71.3% cytotoxicities against K562 cells.CTLs derived from cultures with DCs loaded with frozen-thawed antigen and CD40L were showed 86.9% cytotoxicities against K562 cells.Cytotoxicities by CTLs derived from cultures with unloaded DCs against K562 cells were 37.6% and cytotoxicities by monocytes were 21.1%.Cytotoxicities by CTLs derived from experiment groups were stronger than control groups(P
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AIM and METHODS: To investigate the effect of electrical stimulation of VSA on the firing of thermosensitive neurons in preoptic anterior hypothalamus (POAH), the firing rate of thermosensitive neurons in POAH of 20 New Zealand white rabbits was recorded by using extracellular microelectrode techinque. RESULTS: (1)Electrical stimulation of ventral septal area (VSA) caused a significant increase in firing rate of warm-sensitive neurons in the preoptic area of the anterior hypothalamus(POAH).(2) The firing rate of cold-sensitive neurons was decreased remarkably in the POAH by electrical stimulation of VSA. CONCLUSION: VSA may play a controlling role in the thermoregulation through altering the firing rate of thermosensitive neurons in the POAH .
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AIM:To study the protection of Glycyl-L-Glutamine(Gly-Gln) against myocardial ischemia/reperfusion(I/R) injury in the isolated rat heart.METHODS:A model of myocardial ischemia-reperfusion injury was established with a Langendorff apparatus.Thirty male SD rats were randomly divided into four groups:control group,Gly-Gln group,I/R group and I/R+Gly-Gln group.Both I/R and I/R+Gly-Gln group were pre-perfused for 30 min,followed by 20 min ischemia and 40 min reperfusion.During reperfusion I/R+Gly-Gln group was perfused with Gly-Gln perfusate.Control group was kept perfused for 90 min.Gly-Gln group Gly-Gln perfusate was also kept perfused for 90 min.The left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),?dp/dtmax,heart rate(HR),monophasic action potentials(MAP) was measured during perfusion.The coronary effluent fluid was collected at different certain times.The activities of lactic dehydrogenase(LDH) and creatine kinase(CK) were determined.RESULTS:The isolated rat heart function decreased severely after 20 min ischemia and 40 min reperfusion(I/R):the LVEDP increased and the LVDP,?dp/dtmax decreased.But the LVEDP decreased and the LVDP,?dp/dtmax increased in I/R+Gly-Gln group compared with I/R group.Moreover,the activities of LDH and CK in the coronary effluent fluid decreased remarkably in I/R+Gly-Gln group compared with I/R group.CONCLUSION:Gly-Gln can play a protective role against myocardial I/R injury in isolated rat hearts via maintaining the left ventricular function and decreasing the release of LDH and CK.
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0.05).The expression of glycine receptor ?1 subunit mRNA was increased(P