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33.

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   
34.
Despite a population of nearly 60 million, there is currently not a single interventional radiologist in Tanzania. Based on an Interventional Radiology (IR) Readiness Assessment, the key obstacles to establishing IR in Tanzania are the lack of training opportunities and limited availability of disposable equipment. An IR training program was designed and initiated, which relies on US-based volunteer teams of IR physicians, nurses, and technologists to locally train radiology residents, nurses, and technologists. Preliminary results support this strategy for addressing the lack of training opportunities and provide a model for introducing IR to other resource-limited settings.  相似文献   
35.

Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
36.
37.
BackgroundEpidermal growth factor receptor (EGFR) is frequently overexpressed in metastatic triple-negative breast cancer (mTNBC). One strategy for overcoming resistance to EGFR inhibition is concomitant inhibition of downstream signaling. The antidiabetic drug metformin inhibits both MAPK and PI3K/mTOR pathway signaling. We evaluated the combination of erlotinib and metformin in a phase 1 study of patients with mTNBC.Patients and MethodsPatients with mTNBC who had received at least one prior line of therapy for metastatic disease were eligible. Erlotinib dose was fixed at 150 mg daily. Metformin dose escalation was planned according to a 3 + 3 design. Dose-limiting toxicities (DLT) were assessed during the first 5 weeks of therapy. The primary objective was to determine the maximum tolerated dose of metformin with fixed-dose erlotinib. Secondary endpoints were response rate, stable disease rate, and progression-free survival.ResultsEight patients were enrolled. The median number of prior therapies for metastatic disease was 2.5 (range, 1-6). No DLT events were reported during the DLT assessment period. Most adverse events were grade 1/2. Grade 3 diarrhea despite maximum supportive care required dose reduction of metformin in one patient. Grade 3 rash led to study withdrawal in one patient. No grade 4 adverse events were reported. The best observed response was stable disease in 2 patients (25%). Median progression-free survival was 60 days (range, 36-61 days).ConclusionErlotinib and metformin were well tolerated in a population of pretreated mTNBC patients but did not demonstrate efficacy in this population.  相似文献   
38.
重症心源性肺水肿伴休克患者的机械通气治疗   总被引:3,自引:0,他引:3  
目的研究重症心源性肺水肿伴休克患者机械通气(MV)治疗时通气压力的选择对预后的影响。方法将符合标准的22例患者分为两组对照组9例,常规给予较低通气压力和加强药物治疗;治疗组13例,适当增加通气压力。观察血压、临床症状和动脉血气的变化。结果调整MV后30分钟时,治疗组收缩压迅速由(95±12)mmHg升至(130±15)mmHg(P<0.001),呼吸频率(RR)由(38±11)次/min降至(27±6)次/min(P<0.005),心率(HR)由(126±15)次/min降至(105±12)次/min(P<0.001);对照组上述指标变化不明显。2小时后治疗组的升压药用量减少(70±15)%,对照组则增加(20±5)%;同时在吸氧浓度不变的情况下,治疗组的PaO2由(81±12)mmHg升至(140±15)mmHg(P<0.001),明显高于对照组PaO2的改善。24~48小时内治疗组11例患者(85%)停用升压药,对照组2例(22%)停用。最终治疗组100%的患者好转出院,对照组为45%(P<0.05)。结论与低压力通气相比,适当增加MV通气压力不仅可迅速改善重症心源性水肺肿伴休克患者的低氧血症,也可迅速升高血压,改善心功能,降低病死率。  相似文献   
39.
冠心病合并其他器质性心脏病的外科治疗   总被引:1,自引:0,他引:1  
目的分析冠心病合并其他器质性心脏病的临床特点,探讨一期外科治疗的方法和临床疗效。方法分析2004年4月至2006年4月冠心病合并其他器质性心脏病患者13例,其中风湿性心脏病联合瓣膜病1例,二尖瓣病变4例,二尖瓣退行性病变3例,主动脉瓣关闭不全3例,升主动脉瘤1例,继发孔房缺1例。因冠心病首诊入院5例,以其他器质性心脏病首诊入院8例。术前有心绞痛症状者8例,无心绞痛5例。体外循环下一期外科治疗。结果无死亡病例,13例均顺利出院。冠脉搭桥+瓣膜置换8例,冠脉搭桥+瓣膜成形3例,冠脉搭桥+Bentall+室壁瘤切除1例,冠脉搭桥+房缺修补1例。手术中搭桥1~3支,平均(1.92±0.73)支。术后1周,左心室舒张末内径(LVDD)为(51.77±2.64)mm,较术前[(58.92±3.81)mm]明显缩小(P<0.05)。随访3个月,心绞痛症状完全消失,心功能(NYHA)明显提高(P<0.05)。结论冠心病合并其他器质性心脏病临床症状无特异性,容易漏诊。虽然手术风险性和难度增加,但未得到血液重建,对患者更将是致命性的灾难,应争取一期手术。  相似文献   
40.
目的探讨心脏非黏液性肿瘤临床特点,总结外科治疗经验。方法对我院1996年10月至2005年3月进行外科治疗的56例心脏非黏液性肿瘤的临床资料进行回顾性分析,总结其临床表现、发生部位、肿瘤性质和外科治疗特点等。结果心脏非粘液性肿瘤占本院同期手术患者的0.14%,良性肿瘤28例,恶性肿瘤28例,其中继发性心脏肿瘤8例。良性肿瘤最常见的是生长在心室,共18例;恶性肿瘤最常见的生长部位是心房,共15例。外科治疗行急诊手术者12例。心包开窗引流术2例,探查术1例,术中肿瘤全部切除者26例,部分切除27例,术后住院期间死亡1例。结论心脏非黏液性肿瘤临床表现各异、病理类型多样、病变广泛,手术原则为尽可能切除肿瘤和保持心脏结构的完整性和功能。  相似文献   
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