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2.
Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献3.
MPO和NAT2基因多态性与成人急性白血病易感性 总被引:2,自引:0,他引:2
目的研究髓过氧化物酶(MPO)和N-乙酰基转移酶2(NAT2)基因多态性与成人急性白血病易感性的关系.方法用1∶1配对病例-对照研究方法,收集成人急性白血病患者和对照各139例,应用聚合酶链-内切酶片段(PCR-RFLP)方法分析病例组和对照组MPO和NAT2的基因多态性,比较不同基因型与成人急性白血病易感性.结果 MPO-463A等位基因分布频率病例组低于对照组,MPO(G-463A)各基因型在病例组与对照组中的分布差异有统计学意义(χ^2=7.026,P〈0.05,OR=0.505,95%CI=0.325~0.847).NAT2乙酰化表型频率在病例组与对照组的分布差异无统计学意义(χ^2=2.260,P〉0.05);但NAT2*5 481T等位基因和NAT2*6 590A等位基因分布频率病例组高于对照组(P〈0.05).结论 MPO与成人急性白血病易感性相关,携带MPO(G-463A)突变基因型(GA/AA)个体可降低白血病的发病风险;NAT2乙酰化表型可能与白血病的易感性无关,但NAT2*5(C481T)、NAT2*6(G590A)单核苷酸突变频率病例组明显高于对照组. 相似文献
4.
Kavinder Singh Amteshwar Singh Jaggi Nirmal Singh 《Phytotherapy research : PTR》2009,23(11):1565-1574
The present study was designed to investigate the ameliorative potential of Punica granatum in dextran sulfate sodium (DSS) induced ulcerative colitis. DSS (2%) was administered orally in drinking water for 7 days to induce ulcerative colitis. The extent and severity of ulceration was analysed macroscopically, histopathologically and using a disease activity index. Myeloperoxidase (MPO), a specific marker of inflammation; histamine, a marker of mast cell degranulation; superoxide anion generation and, lipid peroxides were analysed. Administration of DSS resulted in a significant development of ulceration in the colon along with a rise in histamine, MPO activity and oxidative stress. Treatment with Punica granatum extract and its ellagic acid rich fraction (100 mg/kg and 200 mg/kg p.o.) significantly attenuated DSS‐induced colonic inflammation along with attenuation of histamine, MPO and oxidative stress. The antiulcerative effect of Punica granatum extract and its ellagic acid rich fraction were comparable to sulphasalazine (100 mg/kg, p.o.) and sodium cromoglycate (40 mg/kg i.p). It is concluded that Punica granatum has a potential for ameliorating DSS‐induced colitis and its ellagic acid rich fraction may be responsible for this effect. Further, the antiulcerative effects may be attributed to mast cell stabilizing, antiinflammatory and antioxidant actions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
G.
berg B. Simonsson B. Smedmyr T. H. Ttterman P. Venge 《European journal of haematology》1987,38(4):356-362
Bone-marrow regeneration after chemo- and radiotherapy-induced aplasia can be monitored by serum levels of myeloperoxidase (MPO), lysozyme (LYS) and lactoferrin (LF). In 10 patients with leukemia, serum measurements were performed before and after bone-marrow transplantation. Bone-marrow regeneration was suggested by increments in serum MPO and LYS 5 and 4 days prior to the increase in mononuclear cells (Mono) and 10 and 9 d before the increase in polymorphonuclear leukocytes (PMN) in the peripheral blood. LF started to rise 4.5 d before detectable circulating PMNs. 2 patients with early relapses of leukemia post transplantation are shown to display atypical patterns of serum MPO and LYS. We conclude that serum measurements of MPO, LYS and LF may be used as early and sensitive means to monitor bone-marrow activity during hematological regeneration. However, the findings also strongly support the earlier proposal that MPO alone may be used to reflect myeloid activity in the bone-marrow in general. 相似文献
6.
P. M. TIIDUS S. ZAJCHOWSKI D. ENNS D. HOLDEN E. BOMBARDIER A. N. BELCASTRO 《Acta physiologica (Oxford, England)》2002,174(2):131-136
The effects of oestrogen administration on 1 h post‐exercise cardiac muscle myeloperoxidase (MPO) and calpain activities were determined in female rats. Rats were ovariectomized and implanted for 2 weeks with either oestrogen (25 mg 17‐oestradiol) or placebo pellets or left with ovaries intact. Rats were then run for 1 h at 21 m min–1, 12% grade, killed 1 h post‐exercise and cardiac muscle and blood samples were removed. Control animals from each group were killed without prior exercise. Serum oestrogen levels in the order of the highest to lowest were; ovariectomized oestrogen replaced rats > intact ovaries rats > ovariectomized placebo rats. Oestrogen induced significant (P < 0.05) elevations in cardiac MPO activity at rest and at 1 h post‐exercise in ovariectomized rats. No significant elevations in cardiac MPO activity were evident in placebo ovariectomized or normal ovary rats at rest or post‐exercise. Cardiac calpain activities were similar in all unexercised groups. Ovariectomized placebo and intact ovary rats had significantly (P < 0.05) elevated cardiac calpain activities 1 h post‐exercise while calpain activity was not significantly elevated in hearts from ovariectomized oestrogen rats. These results demonstrate that oestrogen supplementation in ovariectomized rats induces elevations in cardiac muscle MPO activities at rest and at 1 h post‐exercise. This is opposite to the effect of oestrogen in post‐exercise skeletal muscle and implies a greater neutrophil infiltration into cardiac muscle caused by oestrogen. This effect cannot be explained by changes in 1 h post‐exercise cardiac muscle calpain activity, the elevation of which was suppressed by oestrogen administration. Oestrogen influences cardiac calpain activity similarly to its effect in skeletal muscle. Thus, oestrogen administration to ovariectomized rats induces elevations in cardiac MPO activity while suppressing cardiac calpain activity. 相似文献
7.
Castardo JC Prudente AS Ferreira J Guimarães CL Monache FD Filho VC Otuki MF Cabrini DA 《Journal of ethnopharmacology》2008,118(3):405-411
Garcinia gardneriana (Planch. & Triana) Zappi (Clusiaceae) is widely distributed in Brazil and used in folk medicine to treat inflammation, pain, and urinary tract and other infections. However, very few studies have analyzed these therapeutic effects. In this study, the anti-inflammatory effects of the hydroalcoholic extracts from Garcinia gardneriana (HEGG) and some of its isolated biflavonoids were evaluated. The results showed that HEGG from the leaves, bark and seeds reduced carrageenan-induced mouse paw inflammation, in addition to diminishing the myeloperoxidase activity in the stimulated tissues. The reduction of neutrophil infiltration by treatment with the HEGG from leaves was confirmed by histology. The leaf extract also reduced the paw oedema evoked by bradykinin, histamine, prostaglandin E2 and 12-O-tetradecanoylphorbol acetate. However, it partially decreased substance P and compound 48/80-caused paw oedema, without any influence on the arachidonic acid-induced oedema. Both of the isolated compounds, fukugetin and GB-2a, prevented the carrageenan-induced paw oedema. In conclusion, this study showed important anti-inflammatory effects of HEGG through its interaction with different intracellular signaling pathways, without interfering with the formation of arachidonic acid (AA) metabolites. These characteristics, in addition to the wide distribution and culturing ease of the plant, confirm its popular use and highlight its promise in the development of new anti-inflammatory drugs. 相似文献
8.
环孢素A对大鼠脑缺血再灌注损伤炎症反应的影响 总被引:3,自引:0,他引:3
目的探讨环孢素A对脑缺血再灌注损伤的保护作用。方法将108只大鼠分为假手术组、生理盐水对照组和环孢素A治疗组,参照Zealonga线栓法制备局灶性脑缺血再灌注模型,大鼠脑缺血2h再灌注22和70h后,分别对各组各时间点大鼠的行为学评分、脑TTC染色、缺血区IL-1β含量和MPO活性进行测定和观察,并对结果进行统计处理。结果各时间点环孢素A治疗组与对照组相比,环孢素A组行为学评分优于对照组(P<0.05);环孢素A组脑梗死灶体积比对照组明显减轻(P<0.05);环孢素A可有效降低大鼠局灶性脑缺血再灌后脑组织中IL-1β的含量(P<0.01);并可显著抑制MPO的活性(P<0.01)。与上述两组相比,假手术组各项观察指标则无明显异常改变。结论炎症反应参与脑缺血再灌注损伤,环孢素A可显著降低缺血再灌注后脑组织中IL-1β的含量、减轻缺血区内白细胞的浸润、对大鼠脑缺血再灌注损伤具有明显的保护作用。 相似文献
9.
Hirokazu Taniguchi Kenjiro Hamamoto Takahiro Nagano Yuji Kishimoto Takashi Kimura Hideki Fujitake Kojiro Yasunaga 《Medical Electron Microscopy》1993,26(1):13-18
Ultrastructural myeloperoxidase (MPO) activity and myeloid-associated antigen (MyAg) expression were investigated in 12 adult
patients with acute lymphoblastic leukemia (ALL). Ultrastructural MPO was detected by 3 different methods. Immunophenotyping
was performed by flow cytometry, using a series of monoclonal antibodies. Ultrastructural MPO-positive blast cells were detected
in 6 patients (50%). In 5 of these 6 patients, the methods detecting both MPO and platelet peroxidase (PPO) activities found
MPO-positive blast cells more frequently than those detecting MPO activity alone. In 2 patients (17%), at least one kind of
MyAg was positive. Ultrastructural MPO activity was detected more frequently than MyAg expression in ALL patients. This method
of detecting PPO and MPO is recommended for detection of ultrastructural MPO-positive ALL. 相似文献
10.
Induction of biologically active antineutrophil cytoplasmic antibodies by immunization with human apoptotic polymorphonuclear leukocytes 总被引:4,自引:0,他引:4
Rauova L Gilburd B Zurgil N Blank M Guegas LL Brickman CM Cebecauer L Deutsch M Wiik A Shoenfeld Y 《Clinical immunology (Orlando, Fla.)》2002,103(1):69-78
Translocation of intracellular components to the cell surface during the priming or apoptosis of polymorphonuclear leukocytes (PMN) is an important mechanism for interaction of antineutrophil cytoplasmic antibodies (ANCA) with these antigens. To test the capacity of apoptotic PMN to trigger production of ANCA, six groups of mice were immunized with either live or apoptotic lymphocytes, or with live, apoptotic, formalin-fixed, or lysed PMN. Mice immunized with both live and apoptotic neutrophils developed high titers of antibodies which gave a granular cytoplasmic immunofluorescent pattern. These antibodies were specific for lactoferrin and myeloperoxidase. Following a second intravenous infusion of apoptotic PMNs, mice developed anti-PR3 antibodies. Vasculitis lesions were not found in mice which developed ANCA. The ANCA-containing IgG fraction induced superoxide production by human PMNs. These results support the hypothesis that neutrophil-specific antigens presented on the cell membranes of apoptotic PMN may induce ANCA in the proper conditions. 相似文献