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971.
Chris H.H. Chan Andrew Hilton Graham Foster Karl M. Hawkins Nafiseh Badiei Catherine A. Thornton 《Artificial organs》2013,37(9):793-801
Infection is a clinically relevant adverse event in patients with ventricular assist device (VAD) support. The risk of infection could be linked to a reduced immune response resulting from damage to leukocytes during VAD support. The purpose of this study was to develop an understanding of leukocyte responses during the in vitro testing of VADs by analyzing the changes to their morphology and biochemistry. The VentrAssist implantable rotary blood pump (IRBP) and RotaFlow centrifugal pump (CP) were tested in vitro under constant hemodynamic conditions. Automated hematology analysis of samples collected regularly over 25‐h tests was undertaken. A new flow cytometric assay was employed to measure biochemical alteration, necrosis (7‐AAD) and morphological alteration (CD45 expression) of the circulating leukocytes during the pumping process. The results of hematology analysis show the total leukocyte number and subset counts decreased over the period of in vitro tests dependent on different blood pumps. The percentage of leukocytes damaged during 6‐h tests was 40.8 ± 5.7% for the VentrAssist IRBP, 17.6 ± 5.4% for the RotaFlow CP, and 2.7 ± 1.8% for the static control (all n = 5). Flow cytometric monitoring of CD45 expression and forward/side scatter characteristics revealed leukocytes that were fragmented into smaller pieces (microparticles). Scanning electron microscopy and imaging flow cytometry were used to confirm this. Device developers could use these robust cellular assays to gain a better understanding of leukocyte‐specific VAD performance. 相似文献
972.
973.
Wang ZK Liu J Liu C Wang FY Chen CY Zhang XH 《Journal of gastroenterology and hepatology》2012,27(10):1629-1634
Background and Aim: Gastric adenomas (GAs) are considered as premalignant lesions of gastric adenocarcinoma. The role of Wnt signaling pathway in GAs is rarely identified. In the present study, we aimed to determine whether Wnt signaling plays a role in the pathogenesis of GAs, and to clarify the mechanism of Wnt signaling in GAs. Methods: The study investigated the relationship between clinicopathological characteristics, Helicobacter pylori (Hp) infection, adenomatous polyposis coli (APC) promoter methylation, APC and β‐catenin immunohistochemistry expression and mutation status, compared with 38 gastric adenoma and periadenomatous tissues (PTs). Results: The abnormal expression of β‐catenin in PTs, low‐grade adenomas (LGAs) and high‐grade adenomas (HGAs) was 0%, 9.09% and 81.25%. For APC, immunoreactive score (IRS) was 5.50 ± 0.5 in PTs, 3.59 ± 1.4 in LGAs and 1.8 ± 2.0 in HGAs. The scores in LGAs and HGAs were significantly lower than those in PTs (P = 0.000). IRS reflected significantly reduced expression of APC in HGAs (P = 0.002). The absent expression of APC had a correlation with the expression of β‐catenin (P = 0.000). Four LGAs (18.18%) and nine HGAs (56.25%) had methylation of APC. APC promoter methylation correlated with the grade (P = 0.014) and the expression of β‐catenin and APC (P = 0.000). Genes mutation was detected in only two adenomas (5.3%). The presence of Hp in HGAs (43.8%) was significantly higher than in LGAs (13.6%) (P = 0.038). But there was no statistical correlation to growth pattern, size, APC hypermethylation and gene mutation. Conclusion: Hypermethylation of APC promoter, instead of mutations involving APC and β‐catenin, may play a role in the development and progression of GAs contributing to moderate activation of Wnt signaling. Helicobacter pylori may accelerate the progress of gastric adenoma, but the pathogenesis needs further research. 相似文献
974.
Prideaux L Kamm MA De Cruz PP Chan FK Ng SC 《Journal of gastroenterology and hepatology》2012,27(8):1266-1280
The incidence and prevalence of inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are lower in Asia than in the West. However, across Asia the incidence and prevalence of IBD has increased rapidly over the last two to four decades. These changes may relate to increased contact with the West, westernization of diet, increasing antibiotics use, improved hygiene, vaccinations, or changes in the gut microbiota. Genetic factors also differ between Asians and the Caucasians. In Asia, UC is more prevalent than CD, although CD incidence is rapidly increasing in certain areas. There is a male predominance of CD in Asia, but a trend towards equal sex distribution for UC. IBD is diagnosed at a slightly older age than in the West, and there is rarely a second incidence peak as in the West. A positive family history is much less common than in the West, as are extra-intestinal disease manifestations. There are clear ethnic differences in incidence within countries in Asia, and an increased incidence in IBD in migrants from Asia to the West. Research in Asia, an area of rapidly changing IBD epidemiology, may lead to the discovery of critical etiologic factors that lead to the development of IBD. 相似文献
975.
Satoh M Vazquez-Del Mercado M Krzyszczak ME Li Y Ceribelli A Burlingame RW Webb TT Sobel ES Reeves WH Chan EK 《Lupus》2012,21(1):68-74
Anti-RNA polymerase III (RNAP III) antibodies are highly specific for scleroderma (SSc) and associated with diffuse SSc and renal crisis. Coexistence of anti-RNAP III and other SSc autoantibodies is rarely documented. We report three cases with coexisting anti-RNAP III and anti-U1RNP. Autoantibodies in 3829 sera from rheumatology clinics were screened by immunoprecipitation. Anti-RNAP III-positive sera were also examined by immunofluorescence and anti-RNAP III ELISA. In total, 35 anti-RNAP III-positive sera were identified by immunoprecipitation, in which three had coexisting anti-U1RNP. All three were anti-RNAP III ELISA positive. Two had anti-RNAP I dominant (vs. RNAP III) reactivity and showed strong nucleolar staining. A case with anti-U1/U2RNP (U2RNP dominant) had systemic lupus erythematosus (SLE)-SSc overlap syndrome; however, the remaining two cases had SLE without signs of SSc. All three cases of anti-RNAP III?+?U1RNP fulfilled ACR SLE criteria but none in the group with anti-RNAP III alone (p?=?0.0002). In contrast, only one case in the former group had sclerodermatous skin changes and Raynaud's phenomenon, vs. 92% with scleroderma in the latter (p?0.05). Although anti-RNAP III is highly specific for SSc, cases with coexisting anti-U1RNP are not so uncommon among anti-RNAP III positives (8%, 3/35) and may be SLE without features of SSc. 相似文献
976.
Aim To examine the effectiveness of a stage‐matched smoking cessation counselling intervention for smokers who had cardiac diseases. Methods A total of 1860 Chinese cardiac patients who smoked at least one cigarette in the past 7 days and aged 18 years or above recruited from cardiac out‐patient clinics in Hong Kong hospitals were allocated randomly to an intervention group or control group. The intervention group (n = 938) received counselling matched with their stage of readiness to quit by trained counsellors at baseline, 1 week and 1 month. The control group (n = 922) received brief counselling on healthy diet at baseline. The primary outcomes were self‐reported 7‐day and 30‐day point prevalence (PP) of tobacco abstinence at 12 months after baseline. The secondary outcome measures included biochemically validated abstinence at 12‐month follow‐up, self‐reported 7‐day and 30‐day PP abstinence and reduction of cigarette consumption by 50% at 3 and 6 months. Results By intention‐to‐treat analysis, the intervention and control groups showed no significant difference in self‐reported 7‐day PP abstinence (intervention: 26.5% versus control: 25.5%; P = 0.60) and 30‐day PP (intervention: 25.4% versus control: 24.2%; P = 0.55), biochemically validated abstinence (intervention: 6.6% versus control: 4.9%; P = 0.14) and overall quit attempts of least 24 hours (intervention: 40.3% versus control: 34.3%; P = 0.007) at the 12‐month follow‐up, adjusted for the baseline stage of readiness to quit smoking. Conclusions An intervention, based on the Stages of Change model, to promote smoking cessation in cardiac patients in China failed to find any long‐term benefit. 相似文献
977.
目的 探讨脑卒中后吞咽功能障碍患者经皮内镜下胃造瘘术(PEG)术前各种因素与术后死亡之间的关系,评估放置PEG管的必要性.方法 52例入组患者,详细记录了PEG前各种参数及术后生存情况,并分析病例的死亡时间特点.对术前和术后的肺炎以及消化道出血情况进行比较分析.结果 52例患者随访期内总共死亡16例,其中15例(93.4%)在术后3个月内死亡.年龄和美国麻醉师协会(ASA)评分显示与死亡有独立相关性,P值分别为0.026及0.001.PEG管置放前后吸入性肺炎发生率(50.0%比34.6%)及上消化道出血的发生率(5.8%比7.7%)比较,差异无统计学意义.结论 放置了PEG管后多数死亡病例是在短期内(3个月)出现.年龄、ASA评分与卒中患者放置PEG管后的死亡风险相关.PEG并不能降低卒中患者吸入性肺炎及消化道出血的发生率. 相似文献
978.
Chan A Verma S Loibl S Crawford J Choi MR Dreiling L Vandenberg T 《Critical reviews in oncology/hematology》2012,81(2):136-150
In this article, we reviewed and quantified reporting of the risk of myelotoxicity, specifically febrile neutropenia (FN), and the related use of supportive care with colony-stimulating factor (CSF) or antibiotics in clinical trials published between January 2005 and June 2009, evaluating emerging regimens for the treatment of selected solid tumors. Our analysis showed that clinically significant neutropenia and neutropenia-related events were generally described in the studies evaluated (grade 3/4 neutropenia incidence, 72%; FN incidence, 53%). However, use of CSF and antibiotics was infrequently and inconsistently reported (trials reporting prophylactic CSF and antibiotics use: in the methods section, 38% and 10%, respectively; in the results section, 19% and 1%, respectively). These results highlight the need for a standardized approach to reporting neutropenic outcomes and use of supportive care measures. This can assist clinicians in prospectively managing relevant toxicities associated with these emerging regimens and thereby facilitate their safe and effective use in clinical practice. 相似文献
979.
Post-chemotherapy cognitive impairment has been an issue of concern in cancer survivors. While most reviews are focused on patient-related factors, it is proposed that drug-related factors may also be determinants. The objective of this review is to study the relationship between the types and dose intensities of chemotherapy regimens on cognitive impairment in breast cancer patients through a systematic literature search. Eighteen prospective studies were selected. The types, dose intensities and durations of chemotherapy regimens received by subjects were compared against prevalence results obtained in individual studies. It was observed that the duration of impairment varied across different generations of chemotherapy regimens. Concurrent administration of multiple cytotoxic agents can lead to a synergistic decline on cognition. Current clinical evidence is insufficient to evaluate the relationship between the types, dose intensities of chemotherapy regimens and cognitive impairment. More investigation is needed to examine the role of pharmacological factors in chemotherapy-associated cognitive changes. 相似文献
980.
Bozkurt B Bolos M Deswal A Ather S Chan W Mann DL Carabello B 《Journal of cardiac failure》2012,18(3):183-193
BackgroundIt is unclear whether improvement in left ventricular (LV) ejection fraction (LVEF) following treatment with a combined α1,β1,β2-blockade can be attributed to improvement in LV contractility, to a reduction in afterload, and/or to improvements in LV remodeling and chamber size. We aimed to examine whether the observed improvement in LVEF following carvedilol treatment is due to changes in intrinsic myocardial contractility beyond changes in LV chamber size or loading conditions.Methods and ResultsIn 49 consecutive patients with chronic heart failure (HF), LVEF ≤35%, NYHA functional class II–IV, on angiotensin-converting enzyme inhibitors but not on ß-blockers, LV contractile performance and remodeling were assessed by comprehensive echocardiography at baseline and after 3 and 6 months of treatment with carvedilol. Carvedilol treatment resulted in significant improvements in LVEF, shortening fraction, and velocity of circumferential shortening (VCFc). There were no significant changes in the mean arterial blood pressure or systemic vascular resistance index; but LV end-systolic wall stress (LVESS), effective arterial elastance, ventriculoarterial coupling, and LV end-diastolic and end-systolic dimensions and volumes were significantly reduced. Estimated end-systolic elastance, VCFc-to-LVESS ratio, and pulsatile arterial compliance significantly improved after 6 months of treatment with carvedilol. The slope of the VCFc relationship to LVESS worsened from 0 to 3 months, but significantly improved from 3 to 6 months.ConclusionsDespite an initial transient negative inotropic effect from 0 to 3 months, carvedilol treatment was associated with a positive inotropic effect with significant improvement in load-independent indexes of myocardial contractility beyond what can be attributed to changes in LV chamber size and load after 3 months. There were no changes in systemic vascular resistance with carvedilol treatment; however, improvement in pulsatile arterial compliance and ventriculoarterial coupling suggested enhanced cardiac mechanoenergetic performance along with improved systemic arterial compliance. 相似文献