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991.
Brain injury associated with deep hypothermic circulatory arrest (DHCA) has been recognized in patients with congenital heart diseases and those undergoing aortic arch surgeries. However, the preclinical investigation of long‐term cerebral injury and recovery mechanisms related to DHCA has been restricted to a satisfactory recovery animal model with a determined recovery time. This study aimed to evaluate the feasibility of a long‐term surviving DHCA model without blood priming in rats, in order to investigate the pathophysiology of long‐term complications in further studies. Twelve Sprague‐Dawley rats were divided into 2 groups: sham group (n = 3) and DHCA group (n = 9). The DHCA group was further assigned to the surviving time of postoperative day 2, 14, and 30 (n = 3, respectively). The entire cardiopulmonary bypass (CPB) circuit consisted of a modified reservoir, a custom‐designed small‐volume membrane oxygenator, a roller pump and a heater/cooler. A 24‐G catheter was cannulated in the branch of the left femoral artery for arterial blood pressure monitoring. Cardiopulmonary bypass was established via the right external jugular vein–right atrium and tail artery. Rats were cooled to a rectal temperature of 18°C, followed by 30 minutes of DHCA with global ischemia. After re‐warming for approximately 40 minutes, the animals were weaned from the CPB at 35.5°C. Blood gas and hemodynamic parameters were recorded preoperatively and intraoperatively, and at 2, 14, and 30 days postoperatively. Thereafter, the brains were perfusion fixed and histologically analyzed. All DHCA processes were successfully achieved, and none of the rats died. Blood gas analysis and hemodynamic parameters at each time point were normal, and vital signs of all rats were stable. Histopathologic deficits in the hippocampus (pathological score, surviving hippocampal neurons, and Ki67‐positive neurons) manifested after 30 minutes of DHCA, which persisted for at least 14 days and recovered after 30 days. A novel and simple long‐term recovery model of DHCA in rats was established in the present study, and histopathologic deficits were observed after clinically relevant 30‐minute DHCA durations, in order to determine the 30‐day recovery time frame. 相似文献
992.
Taoping Bai Yuqiu Liu Jiche Liu Chenhao Yu Wentao Jiang Yubo Fan 《Journal of vascular surgery》2019,69(2):581-591.e1
Objective
This article compares the effect of different surfactants on foam stability and determines the foam decay relationship, so that the suitability of surfactants in a clinical setting can be evaluated.Methods
Five different surfactants were used to prepare sclerosing foam at room temperature using a liquid:gas ratio of 1:4 in vitro. Foam decay experiments were performed for each sample using a laboratory-made foaming apparatus, and the process was recorded using a video camera. The stability indices used included the drainage time, drainage rate, half-life, foam half-life volume, surfactant stability index, and foaming index.Results
The sodium morrhuate foam was relatively more stable than the polidocanol foam, but exhibited weak foaming. After the addition of the surfactants, the foam half-life was less than 300 seconds. The effect of the surfactants on the stability of the sodium morrhuate foam was more pronounced. The surfactant stability indices could be arranged as follows: poloxamer 188 > Tween 80 > macrogol 4000 > propanediol > lecithin. However, the differences in the foaming indices were small.Conclusions
Of the five surfactants tested, poloxamer 188 has best performance to enhance sclerosing foam stability. The addition of the surfactants improved the stability of the sclerosing foams. It was observed that the relationships between the foam half-life and the surfactant stability index and the surfactant concentration follow the power law. 相似文献993.
994.
Ingigerður S. Sverrisdóttir Sigrún H. Lund Ingemar Turesson Magnus Björkholm Lynn R. Goldin Ola Landgren Sigurður Y. Kristinsson 《British journal of haematology》2019,186(1):37-44
Parental longevity is associated with an increased life expectancy; results with regard to specific diseases are conflicting. There are limited data focusing on host characteristics and their effect on survival among multiple myeloma (MM) patients and individuals with monoclonal gammopathy of undetermined significance (MGUS). Therefore, our aim was to evaluate the impact of parental longevity on survival of patients with MM and MGUS. A total of 4675 patients with MM, 6812 MGUS patients and 13 398 population-based controls for MM as well as 19 110 controls for MGUS, from 1988 to 2013, were included in the study. Longevity was defined as >90 years of age. Among MM patients, parental longevity was associated with a decreased risk of death [hazard ratio (HR) = 0·92, 95% confidence interval (CI) 0·84–0·99] and the same was true for MGUS patients (HR = 0·87, 95% CI 0·78–0·96). Having one long lived parent significantly decreased the risk of death in both groups, but was not statistically significant when both parents exceeded 90 years of age. In conclusion, parental longevity decreases the risk of death for patients with MM and MGUS which may reflect the importance of the host's genetic and environmental factors in relation to survival. 相似文献
995.
Hong-Sheng Zhang Qian Liu Chun-Mei Piao Yan Zhu Qiang-Qiang Li Jie Du Hong Gu 《The Canadian journal of cardiology》2019,35(12):1851-1856
BackgroundThe relationship between clinical outcomes and gene mutations in Chinese pediatric patients with idiopathic and heritable pulmonary arterial hypertension (PAH) is unclear.MethodsWe retrospectively studied the clinical characteristics and outcomes of pediatric patients who visited Beijing Anzhen Hospital from September 2008 to December 2018.ResultsEighty-two pediatric patients were included. Forty-two gene mutations were identified in 41 patients (50%), including 25 mutations in BMPR2, 5 mutations in ACVRL1, 3 mutations each in ABCA3 and NOTCH3, 2 mutations each in KCNK3 and HTR2B, 1 mutation in ENG, and 1 mutation in EIF2AK4. The mean age at diagnosis of PAH was 86.4 ± 55.1 months. Forty-eight patients (twenty-eight mutation carriers) underwent cardiac catheterization examinations, with acute vasodilator testing performed simultaneously. Results showed that mutation carriers demonstrated a higher pulmonary vascular resistance index (P = 0.037). Patients with gene mutations responded poorly to vasodilators (P = 0.001). The 1-, 2-, and 3-year survival rates of mutation noncarriers were 95.1%, 87.8%, and 82.5% respectively; while for mutation carriers, the proportions were 86.6% (P = 0.216), 63.8% (P = 0.021), and 52.2% (P = 0.010), respectively. Cardiac index was an independent predictor of death (P = 0.005; odds ratio [OR] 2.16, 95% confidence interval [CI] 1.258-3.704), as well as RAP (P = 0.01; OR 1.26, 95% CI 1.056-1.503).ConclusionsIn our cohort of Chinese pediatric patients, those with an identified gene mutation demonstrated worse clinical outcomes. Therefore, early gene screening for pediatric patients with idiopathic and heritable PAH is recommended, and more aggressive treatment for mutation carriers may be advisable. 相似文献
996.
997.
998.
B. Davido R. Batista H. Fessi H. Michelon L. Escaut C. Lawrence M. Denis C. Perronne J. Salomon A. Dinh 《Médecine et maladies infectieuses》2019,49(3):214-218
Objective
A rapid and worrying emergence of vancomycin-resistant enterococci (VRE) gut colonization is occurring worldwide and may be responsible for outbreaks, especially in healthcare facilities. While no efficient decolonization strategies are recommended, we assessed fecal microbiota transplantation (FMT) to eradicate VRE colonization.Patients and method
Our main objective was to measure the impact of FMT on decolonization of VRE carriers, confirmed by at least two consecutive negative rectal swabs at one-week interval during a 3-month follow-up period. Patients received no antibiotic prior to the FMT.Results
After a month only three patients remained colonized with VRE. Decolonization was associated with 87.5% (n = 7) of success after three months as only one patient remained colonized.Conclusion
Our first results confirm that the FMT seems to be safe, with an impact on VRE colonization over time that may help control outbreaks. 相似文献999.