The multi-potent differentiation capability of mesenchymal stem cells (MSCs) implies potential to achieve patient-specific regenerative therapy for myocardial infarction. However, it is evident that transplanted stem cells do not survive well in the harsh ischemic microenvironment. Erythropoietin (EPO) has been shown to be a potent inhibitor of neuronal and myocardial apoptosis. Here, we investigate the cell viability and the change of erythropoietin signal pathway of MSCs challenged by hypoxia treatment.Methods MSCs were derived from the bone marrow of 2-week-old Wistar rats and expanded. Hypoxia treatment of cells was performed using a ProOx-C-chamber with the oxygen concentration set to 0.5% for the times required.Results The rate of trypan blue staining was 3.5% ± 0.4% in control group, and 3.9% ± 0.2%, 5.0% ±0.5%, 7.1% ± 0.5% in the groups treated with hypoxia for 24, 48, 72, 96 hours. Western blot analysis suggested the expression of EPO in MSCs was significantly upregulated after 48-hour treatment with hypoxia, which was further confirmed by immunofluorescence staining. There was higher and earlier expression of EPOR. And the expression level of total ERK remained constant during the hypoxic treatment. However, the expression of HIF-1α phosphorylated ERK was significantly upregulated after 24-hour treatment with hypoxia and peaked at 72 hours.Conclusions MSCs is not sensitive to hypoxia insult alone. The components in EPO signal pathway (e. g.EPO, EPOR and P-ERK) is upregulated in MSCs after hypoxic treatment, which suggests that EPO signal pathway plays an important role in the hypoxia-tolerance and paracrine protecting capability of MSCs.

Objective To explore the effects of vascular endothelial growth factor (VEGF) and nitric oxide (NO) on coronary collateral blood flow (CCBF) in a rabbit model of physical ischemic training (PIT),and to provide a foundation for the study of the mechanism of collateral circulation formation in PIT.Methods Models of intermittent myocardial ischemia were established in 55 rabbits by installing a water balloon constrictor on the left ventricular coronary artery.The rabbits were then divided into a sham-operation group,a pure ischemia group,a PIT group,a PIT group with NO inhibition pretreatment,a PIT group with VEGF inhibition treatment,and a PIT group with both NO and VEGF inhibition pretreatment.Microspheres were injected at modeling and before sacrifice before and after ischemic stimulation.At the termination of the experiment the ischemic myocardial tissue of the left ventricular anterior wall was sampled,and then relative CCBF was measured using the microspheres.Results There was no significant difference among the 6 groups before training.After training prominent differences among the groups were observed,with the PIT group having the greatest increase in CCBF.CCBF in the pure ischemia group,the PIT group,and the PIT group with NO inhibition pretreatment were significantly higher than in the sham-operation group.Significant differences were also found between the PIT group and the three pretreatment groups.CCBF in the PIT group with NO pretreatment and VEGF inhibition was significantly different from that in the NO pretreatment group,while it was not found in the group with VEGF inhibition pretreatment.The CCBF in the group with VEGF inhibition pretreatment and the group with NO inhibition pretreatment was similar.Conclusions PIT can improve CCBF to the remote ischemic myocardium when combined with VEGF and NO pretreatment.Blocking VEGF or NO can reduce CCBF after training,and both VEGF and NO are involved in the formation of collateral circulation,with VEGF playing the major role.

Objective To evaluate the value of S100B gene on cardiovascular remodeling in rats with abdominal aorta coarctation.Method Sprague-Dawley rats(sanitary degree,male),weighring(220～240)g,were used in the study.They were provided by College of Medicine,Zhejiang University.The abdominal aortas of rats were isolated and constricted so as to establish models of heart failure;the abdominal aortas of another ten rats were isolated but not ligated(sham-operation group).After one week,the 20 rats were alive and randomly divided into 2 groups:operation group(n=10)and Carvidilol-operation group(Car group,n=10).Car Group was treatedwith 2 mg·kg-1per day Carvedilol and operation group was administered with the same doses of normal saline.After 4 weeks,a catheter was inserted through the right jngular artery into the left ventricle to record hemodynamic.Then all rats were euthanized,and the heart tissues were rapidly excised,rinsed with PBS.The left ventricles were then cut into two parts at the equator:the upper sections were fixation,the lower sections were stoted at-80℃,at 100 mg per tube.LV transverse section(4μm thick)was subjected to S100B immunehistoc- hemistry.RNA was iselated from tissues by Trlzol to determine levels of S100BmRNA and β-actinmRNA by RT- PCR.The data was expressed as(x±s);One-way analysis of variance was used for comparison among groups, and Student-Newman-Keulsa test for comparison between two groups.Statistical significance was set at P＜0.05. Results In Operation Group,there was a decrease in maximal rate of systolic and diastolic of left ventricular pressure(±dp/dtmax)[(1543.6±277.9)mmHg/s vs.(2640.4±481.3)mmHg/s and(-1352.5±202.3) mmHg/s vs.(-1873.2±412.3)mmHg/s];and an increase in left ventricular end diastolic pressure(LVEDP) [(24.8±5.2)mmHg vs.(2.1±0.7)mmHg]compared with sham-operation group(P＜0.01,P＜0.01 and P＜0.05).And in Car group,the level of LVEDP was just in the midst of the Operation Group and sham-opera- tion group,and had statistical significance(P＜0.01);while±dp/dtmac[(2372.3±92.6)mmHg/s and (-1786.4±62.6)mmHg/s]were much higher than those in operation group(P＜0.01).There were no any S100B positive cells and expression of S100B mRNA in sham-operation group;while there were much more S100B positive cells in operation group than those in Car group(P＜0.01).The expression of S100B mRNA in operation group was more pronounced than that in Car group.Changes in expression of S100BmRNA were positively correlat- ed with changes in LVEDP(r=0.847,P＜0.01);while changes in expression of S100BmRNA were negatively correlated with changes in±dp/dt max(r=-0.853 and-0.689,beth P＜0.01).Conclusions There was hish expression of S100B in myocytes from rats with experimental heart failure and negative correlation between the expression of S100B and heart function.It indicated that S100B could play a negative role in heart failure.

BACKGROUND: In a series of recent studies it was demonstrated thatpolysaccharides play important roles in many physiologic and pathologicprocessions, such as infection, inflammation, inter-cell adherence and sig nal conduction, immune identification, cell proliferation and differentiation, as well as maintenance of cell structure and function. But the protectiveeffect of plant polysaccharides on gastrointestinal mucosa needs further re search. OBJECTIVE: To observe the effect of the total polysaccharides of SijunziDecoction (SJZD) (TPSJ) in different concentrations on the proliferation ofrat intestinal epithelial cell line IEC-6. DESIGN: Observational controlled trial. SETTING: Central Laboratory, Guangdong Hospital of Traditional ChineseMedicine. MATERIALS: ①Cell line: The IEC-6 of normal rats (Catalog No. RL 1592) was purchased from American Type Culture Collection (ATCC). IEC6 cells were originated mainly from intestinal crypt cells. ②Reagents anddrugs: DMEM medium, bovine insulin, gentamicin, fetal bovine serum (FBS) and DPBS were purchased from GIBCO Ltd. Cell proliferation kit(MTT) was purchased from Roche Ltd. Indomethacin was purchased fromSigma Company. SJZD was composed of Dangshen (Codonopsis pilosula),Baizhu (Atractylodes macrocephala), Fuling (Poria cocos) and Gancao (Glycyrrhizae uralensis), and these four drugs were in same ratio as Pharmacopoeia. The four herbs were boiled in water, extracted twice for 8 hours.Extract was combined, decompressed, concentrated, centrifugated with high speed to take out insoluble substance, put in glass paper to receive reverse lotic water dialysis for 2 hours. The final decoction was concentrated by heating followed by extraction with 80% ethanol. After overnight precipitation at room temperature and combination of sedimen, the total polysaccharide was obtained by deproteinating with the Sevag method.METHODS: ①The IEC-6 cell line was maintained in T-150 flasks with DMEM culture solution, and then put in CO2 incubator at 37 ℃, at saturated humidity, cultured at 0.05 volume fraction CO2, after being taken out from dry ice and defrosted rapidly in water-bath at 37 ℃. Flasks were incubated at 37 ℃ in 5% CO2· Stock cells were subcultured at a dilution of1:7 every 5-7 days and the medium was changed once every 2 days. The cells in passage 15-20 were used for testing. ②IEC-6 cells were inoculated at a density of 1×l04 cells/well in 96-well plates. Cultured were supplemented with TPSJ in a final concentrations ranging from 50, 100 and 200 mg/L after 6 hours, which was 3 TPSJ groups. One plate would be taken out for the examination of cell proliferation using MTT assay everyday. The cells that not administrated by any intervention were used as normal control group and cell proliferation was assayed using MTF at corresponding time points. ③IEC-6 cells were inoculated at a density of1×104 cells/well in 96-well plates, and then cultured in the DMEM supplemented with no serum from the following day for 24 hours. For the examiation of mucosal restitution, indomethacin at concentration of 40 mmol/L was employed to induce IEC-6 cells injured, which was indomethacin group. The three concentration of TPSJ was 50, 100 and 200 mg/L, respectively, which was 50,100,200 mg/L TPSJ groups. After drug action for 20 hours, the proliferation of cells was measured using MTT according to the manufacturer's instructions. IEC-cells without any intervention were used in the normal control group. Cell proliferation was determined with TT method at corresponding time points.MAIN OUTCOME MEASURES: MTT assay was used to examine the effects of TPSJ on IEC-6 cell proliferation in different times. MTT assay was used to detect the effect of TPSJ on IEC-6 cell proliferation inhibited by indomethacin.RESULTS: TPSJ could accelerate IEC-6 cells growth at different doses and in different time. After the cells were treated by 40 mmol/L indomethacin for 24 hours, the absorbance (A) of IEC-6 cells apparently declined compared with that in the normal control group (0.17±0.02,0.31±0.03; P ＜ 0.01). The A of IEC-6 cells treated by TPSJ in 100 mg/L group was apparently higher compared with indomechacin group (0.25±0.04, 0.17±0.02; P ＜ 0.01). The A of IEC-6 cells treated by TPSJ did not restored to the normal level, but there was no insignificant difference compared with normal group (P ＞ 0.05).CONCLUSION: TPSJ can accelerate the proliferation of IEC-6 cells. TPSJ can exert regulatory function both in intestinal mucosa absorption and immunity by affecting intestinal epithelial cells.

Objective To provide reference for establishing diagnosis and differential diagnosis methods of rare yeast-like fungal bloodstream infection for clinical microbiology laboratory.Methods Trichosporon asahii (T.asa-hii)and Geotrichum capitatum (G.capitatum)bloodstream infection was diagnosed and differentially diagnosed through clinical data analysis,morphological examination,biochemical reactions,and molecular biology technology. Results Two types of yeast-like fungal bloodstream infections in case 1 and case 2 both occurred in leukemia agranulocytosis phase after chemotherapy,such infections were serious and highly similar.The cultivated colonies on blood agar plates of case 1 and case 2 were performed gram stain and microscopic examination.Hyphae,arthro-spores and microconidia were visible in the former,thickness of hyphae branches and length of arthrospores were different,most presented rectangular and barrel shape;the latter can be seen hyphae with transparent septum bro-ken up into arthrospores,presented rectangular shape,did not produce blastoconidia.Identification with API 20C AUX showed that they were T.asahii and G.capitatum.The PCR product sequences were compared with NCBI, suggesting that T.asahii and G.capitatum were at sexual stage.Conclusion Comprehensive application of a varie-ty of technical methods is helpful for improving the diagnosis accuracy of bloodstream infection with yeast-like fungi, identifying Trichosporon and Geotrichum to the species level may help physicians to understand such rare fungal in-fection,choose antifungal agents rationally,and improve clinical prognosis.

OBJECTIVETo explore the integrative quantitative index of the extent of pneumoconiotic changes by dusts and to evaluate the extent of pulmonary injury by the dusts containing different contents of free silica.

METHODSIn accordance with the morphometric principle, the areas of each kind of pathologic changes in the lung tissue sections of pneumoconiosis model were measured by utilizing a computer-aided graphic analyzer, and the volume density of each pathologic change and the value of pulmonary injury by dust(VPID) were calculated. Meanwhile the extent of pulmonary injury were compared among the rat groups treated with the dusts containing different contents of free silica.

RESULTSThere were significant differences among each groups in the volume density of some pathologic changes in the same exposed periods. There were significant correlation between VPID and the content of free silica dust or the lung collagen content (r = 0.535-0.849, P < 0.005 or P < 0.01). Furthermore, the degree of cor relationship of VPID with both of the latter were higher than the sum of unweighted volume density of the various pathologic changes in lung.

CONCLUSIONIt is suitable, reasonable and simple to use VPID an index to indicate the extent of pulmonary injury by dust and to diagnose pneumoconiosis in pathology, and the extent of pulmonary injury by dust may be aggravated with the increasing of the content of free silica.

Animals ; Dust ; Lung ; pathology ; Pneumoconiosis ; pathology ; Rats ; Silicon Dioxide ; toxicity

OBJECTIVETo analyze the results of the first-stage toxicological evaluation of 1 502 pesticide samples.

METHODSThe classification of the 1 502 pesticide samples was analyzed, and the experimental results of the samples in different years were compared.

RESULTSMost of the 1 502 pesticide samples were insecticides, accounting for 52.5% of all, followed by bactericides and herbicides. In the 5 years, the proportion of biogenic insecticides showed a significant rising trend (χ² = 11.426, P < 0.05). The proportion of single pesticides was 65.8%; mixed pesticides accounted for 32.7%; original pesticides accounted for only 1.5%. From 2008 to 2012, most pesticides had low toxicity, regardless of the exposure route (via the mouth, skin, or respiratory tract). Acute oral and dermal toxicity tests showed that pesticides with moderate toxicity declined year by year (oral exposure χ² = 18.036, P < 0.01; dermal exposure χ² = 40.482, P < 0.01). There was a small proportion of pesticides with high toxicity. We did not detect any pesticide with extreme toxicity. Acute skin irritation and eye irritation test showed an upward trend in proportion of non-irritating pesticides (χ² = 77.110, P < 0.01; χ² = 12.693, P < 0.05), while the proportion of medium-irritation pesticides decreased significantly (χ² = 18.941, P < 0.01; χ² = 13.129, P < 0.05). Sensitization test showed that all samples were weak sensitizers.

CONCLUSIONThe major type of investigated pesticides was insecticide. Most samples were single pesticides, and there was a certain proportion of mixed pesticides. Novel pesticides such as bio-pesticides are the development tendency. The tested pesticides were mainly low-toxicity pesticides, with a certain proportion of medium- and high-toxicity pesticides. Personal protection should be strengthened during production and use of pesticides.

Animals ; Pesticides ; classification ; toxicity ; Toxicity Tests, Acute

This paper summarized the operation cooperation and management of the first case of bilateral lung transplantation assisted with double extracorporeal membrane oxygenation (ECMO) for the recipient with novel coronavirus pneumonia (COVID-19) in the world. The bilateral lung transplantation assisted by double ECMO had been accomplished successfully on a recipient with COVID-19, who was supported by ventilator and ECMO, with other organs function basically normal. The operation took 405 min and went smoothly. The cooperation and management guidelines of the operation room included the following: setting up of COVID-19 emergency operation group quickly; listing and preparing of the detailed operation supplies; transferring of the whole system of lung transplantation operating room in Wuxi People's Hospital to the Wuxi No.5 People's Hospital (isolation hospital); reconstruction of a negative pressure operating room for lung transplantation; formulating and strictly implementing the guidelines and management process for the operation of patient with COVID-19.