1.A study on the effect of preservatives on the stability of carboxyhemoglobin in the blood samples
Gaoqin ZHANG ; Daming ZHANG ; Chaojin SONG ; Keming YUN ; Ai WANG
Chinese Journal of Forensic Medicine 2010;25(1):20-23
Objective To investigate the effect of conventional preseratives on the stability of carboxyhemoglobin(HbCO)in the stored blood samples.Methods Blood samples with 30%~40% and 60%~70% of HbCO were established,respectiviely.The samples were stored with the commomly used preseratives including formaldehyde,sodium fluoride,EDTA-Na_2,sodium nitrite,potassium oxalate,heparin sodium,sodium citrate and the mixture of sodium fluoride and sodium citrate(1:3).Saturation of HbCO in the preserved blood samples were determined at 0h,2h,8h,24h,3d,and 7d after treatment with the addictives,respectively.The data were evaluated statistically.Results The stability of HbCO was significantly affected in the formaldehyde and sodium nitrite-treated samples,but no significant effects of the other preseratives on the blood samples were detected.Conclusion The stability of HbCO in the blood samples conserved varies with the type of the preseratives used.The samples taken from cases with suspected death from carbon monoxide poisoning should be kept with proper preseratives.Blood samples preserved with formaldehyde and sodium nitrite are not suitable for HbCO determination.
2.Effects of CX3CL1 and CCL2 on the expressions of angiogenesis-related factors of human monocyte-derived macrophages
Gaoqin, LIU ; Lei, CHEN ; Yuan, CHEN ; Wenjuan, ZHOU ; Wenpeng, ZHANG ; Peirong, LU
Chinese Journal of Experimental Ophthalmology 2014;32(3):206-210
Background Intracorneal macrophages play a critical role in corneal neovascularization (CNV)by secreting relative chemokines.But macrophages are characteristic by heterogeneity which has different biologic functions under different induction or stimulation from microenvironment.Objective This study was to detect the effects of chemokine (C-X3-C motif) ligand 1 (CX3CL1) and chemokine (C-C motif) ligand 2 (CCL2) on macrophages in vitro.Methods CNV was induced by corneal alkali burn in the left eyes of 20 male BALB/c mice aged 7-8 weeks.The CNV was evaluated under the slit lamp microscope 4 days after alkali burn,and then the corneal sections were prepared after mice were sacrificed.The expressions of CCR2 and CX3CR1 in the corneal specimens were detected by histo-fluorescence staining.Human peripheral blood mononuclear cells were separated using density gradient centrifugation and incubated in RPMI-1640 medium containing 10% fetal bovine seruml(FBS) with 30 μg/L granulocyte-macrophage colony-stimulating factor (GM-CSF).The cells were divided into CD68 +CCR2 group and CD68+CX3CR1 group,and the percentage of the CX3CR1 and CCR2 expressions in the infiltrated macrophages of corneal specimens and human monocyte-derived macrophages was assayed by flow cytometry.The cultured cells were stimulated using human recombinant CX3CL1 and CCL2 proteins,and real-time PCR was used to detect the relative expressions of angiogenesis-related factors in macrophages.Results CNV was found in corneas 4 days after alkali burn and the CNV onsets from corneal limbus to central zone observed by a slit lamp.CCR2 and CX3CR1 were expressed in the F4/80-positive macrophages in alikali burned corneas.The macrophages grew for two weeks and appeared more dead cells in without GM-CSF group,but in GM-CSF induced group,the number of macrophages was increased.The percentage of CX3CR1-positive cells was 75% and that of CCR2-positive cells was 45%.Real-time PCR showed that expression level of vascular endothelial growth factor (VEGF) mRNA increased and that ADAMTS-1 mRNA or TSP-1 mRNA decreased on macrophages after CCL2 stimulation,with significant differences in the 150 mg/L CCL2 group compared with the control group (t =-5.09,P =0.03 ; t =3.01,P =0.04 ; t =4.27,P =0.02).However,the VEGF mRNA expression decreased and ADAMTS-1 mRNA and TSP-1 mRNA increased after CX3CL1 stimulation,showing significant differences between the 150 mg/L CX3CL1 group and the control group (t=6.35,P=0.O2;t=-2.92,P=0.04; t=-3.81,P=0.03).Conclusions These results suggest that the macrophages have high heterogeneity.CCL2-and CX3CL1-expressing macrophages can regulate the expressions of angiogenesis-related factors.Macrophage chemokine signal may be a good target for treatment of neovascular ocular disease.
3.Inhibitory effect of tight junction protein on experimental corneal neovascularization
Gaoqin, LIU ; Xuefei, HE ; Zhigang, CHEN ; Jing, XU ; Peirong, LU ; Xueguang, ZHANG
Chinese Journal of Experimental Ophthalmology 2014;32(9):773-779
Background Corneal neovascularization (CNV) is one of the causes of corneal blindness.Studies showed that zonula occludens-1 (ZO-1) can inhibit pathological angiogenesis through physical barrier formed by tight junction structure.However,whether ZO-1 plays a role in CNV is unclear.Objective The aim of this study was to explore the effect of ZO-1,a tight junction protein on experimental CNV.Methods The CNV models were established in the left eyes of 24 clear male BALB/c mice aged 7-8 weeks by putting NaOH filter paper in the center of corneas for 15 seconds (15 s group) or 40 seconds (40 s group).CNV was examined and evaluated under the slit lamp microscope,and the expression of ZO-1 mRNA in the corneas were detected and compared by reverse transcription PCR (RT-PCR) between the two groups 2 weeks after modeling.In addition,54 models created by the same method were assigned to 3 groups according to randomized number table,0.2% hyaluronic acid (HA),antiZO-1 neutralizing antibody (10 mg/L) +0.2% HA and mouse hypoxia inducible factor-1α (HIF-1α) recombinant protein (5 mg/L)+0.2% HA were topically administrated in the mice three times a day for 1 week after modeling respectively.The corneas were extracted 2 weeks after application of the drugs.Expression of CD31 in the CNV was assayed to calculate the number and the area of CNV by immunohistochemistry.The expression of VEGF mRNA in the corneas was detected by RT-PCR.The percentages of macrophage-specific F4/80 positive cells and neutrophilsspecific Ly-6G positive cells were calculated to evaluate the infiltrations of inflammatory cells in the corneas by flow cytometry.Results In 2 weeks after alkali burn of corneas,the number of severe CNV was more in the 40 s group than that in the 15 s group (x2 =6.032,P=0.049),and the expression level of ZO-1 mRNA was lower in the 40 s group than that in the 15 s group (1.15±0.08 versus 1.53±0.04) (t=4.157,P=0.014).CD31 positive cell number was more and the staining area was larger in the ZO-1 antibody group and HIF-1α positive control group than those in the 0.2% HA group (cells:t=-129.590,-226.820,both at P=0.000;area:t =-5.310,-8.840,both at P=0.000).The relative expressions level of vascular endothelial growth factor (VEGF) mRNA was 1.33±0.10 and 1.46±0.11 in the ZO-1 antibody group and HIF-1 α positive control group respectively,which were significantly higher than 0.93±0.06 of the 0.2% HA group (t =-5.820,-7.284,both at P =0.000).The percentages of positive cells in the ZO-1 antibody group and HIF-1α positive control group were significantly increased in comparison with the 0.2% HA group for F4/80 (t =-16.750,-17.480,both at P =0.000) and for Ly-6G (t =-21.450,-27.680,both at P=0.000).Conclusions Alkali burn induced CNV downregulates the expression of ZO-1 mRNA.Administration of ZO-1 antibody causes the rise of VEGF mRNA in CNV and the infiltration inflammation cells,which suggests that the influence of ZO-1 on CNV is associated with the expression of VEGF.