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71.
Khan S Okamoto T Enomoto K Sakashita N Oyama K Fujii S Sawa T Takeya M Ogawa H Yamabe H Akaike T 《Microbiology and immunology》2012,56(3):145-154
Helicobacter cinaedi has been increasingly recognized as an emerging pathogen. Reports of recurrent bacteremia and isolation of H. cinaedi organisms from a patient with myopericarditis led us to postulate that H. cinaedi is associated with chronic inflammatory cardiovascular diseases such as atrial arrhythmias and atherosclerosis. To assess any association of H. cinaedi with atrial arrhythmias, a retrospective case-control study of patients attending Kumamoto University Hospital from 2005 to 2009 was performed. The arrhythmia status of these patients was determined from their electrocardiography and electrophysiological studies. Multiple logistic regression analysis was used to identify independent risk factors. In a comparison of case patients (n= 132) with control subjects (n= 137), H. cinaedi seropositivity was identified as an independent risk factor for atrial arrhythmia (odds ratio, 5.13; 95% confidence interval, 3.0-8.7; P < 0.001). There were no significant differences, however, between these two groups with respect to anti-H. pylori IgG concentrations, anti-Chlamydophila pneumoniae IgG concentrations, and other studied variables. IgG concentrations against H. cinaedi and H. pylori were inversely correlated, which suggests cross-immunity between these two bacteria. Also, to explore any association of H. cinaedi with atherosclerosis, immunohistochemical analysis of atherosclerotic aortic tissues collected post mortem from nine patients was performed. Immunohistochemistry of atherosclerotic aortic tissues from all nine patients detected H. cinaedi antigens inside CD68(+) macrophages. These findings provide the first evidence, to our knowledge, of a possible association of H. cinaedi with atrial arrhythmias and atherosclerosis. 相似文献
72.
Miller LJ 《Zoo biology》2012,31(2):242-248
Many publications within the field of zoo animal welfare have stated the importance of decreasing stereotypic behavior (e.g., pacing) to help ensure a positive visitor experience. The idea behind these statements is that visitors want to see animals engaged in natural behavior. Additionally, it is thought that watching an animal exhibit species-appropriate behavior could help increase a visitor's connection to wildlife and ultimately their interest in conservation. However, until recently, no information was available to validate such statements. The purpose of this research was to examine people's reaction to viewing an animal engaged in pacing behavior. Participants were randomly selected to fill out a survey after watching a short video of either a tiger pacing or resting (control). Results indicate that having viewed a tiger pacing significantly decreases people's perception of the level of care animals receive at that facility. In addition, people's interest in supporting zoos decreased as a result of viewing this behavior. Results are discussed from an animal welfare, business, and conservation perspective. 相似文献
73.
目的应用微电极阵列芯片(microelectrode arrays chip,MEA)技术评价48 h房颤(atrial fibrillation,AF)犬左、右心耳(LAA、RAA)的电生理特性。方法随意来源犬12只,以600次/分起搏右心房建立AF模型,分为48 h AF组(n=6)和对照组(n=6)。造模成功后迅速开胸剪取LAA、RAA,置于盛有台式液的MEA中,分别记录AF组及对照组LAA、RAA场电位(field action potential,FAP)形态、振幅、放电频率及激动传导情况。结果 AF组LAA、RAA组织FAP节律绝对不齐,LAA(185.22±25.62)次/分,较对照组(156.44±8.88)次/分增加15.67%(P〈0.01),RAA(102.39±16)次/分,较对照组(156.44±8.88)次/分减慢34.62%(P〈0.01)。48 h AF组LAA组织电压(458.33±26.73)μV较对照组(740.55±18.93)μV降低38.11%(P〈0.01),RAA(504.83±39.93)μV较对照组(840.56±18.93)μV明显降低(P〈0.01),48 h房颤组LAA组织FAP时程(45.28±8.59)ms较对照组(70.77±6.98)ms缩短15 ms(P〈0.01)。RAA(61.78±7.1)ms较对照组(75.83±7.63)ms缩短14 ms(P〈0.01)。48 h AF组LAA、RAA FAP传导异质性增加。结论应用MEA技术可反映心肌组织片场电位电生理特性,48 h AF后LAA放电频率增加,频率绝对不齐,LAA、RAA电压降低,场电位时程延长。 相似文献
74.
The stereotypies of individually caged Asiatic black bears (Ursus thibetanus) and Malayan sun bears (Helarctos malayanus) were studied in detail. Stereotypies were performed by 27 of the 29 subjects, were primarily locomotory in form (e.g., pacing), and occupied on average 18% (standard error of the mean (SEM)=2.5) of daylight hours. Stereotypy levels during the night were almost negligible and were highly correlated with daytime levels. Total stereotypies peaked prior to food arrival, although oral stereotypies were most frequent after feeding. In general, stereotypies were performed in locations from which food arrival could be viewed, although Asiatic black bears were equally likely to exhibit stereotypy near a neighboring bear. Across individuals, stereotypy frequency was inversely correlated with inactivity and increased with age. Older bears also showed less normal activity and a reduced diversity of normal behavior. Stereotypy levels were unrelated to levels of “compulsive” behavior (e.g., hair plucking) or repetitive self‐sucking–a potential deprivation stereotypy. More frequent stereotypies were performed more invariantly (i.e., were more predictable from one repetition to the next) and in more diverse contexts, namely 1) outside the pre‐feeding period, and 2) during the night. Contrary to observations reported elsewhere, higher frequencies of stereotypy were not associated with reduced behavioral diversity, or with a more elaborate repertoire of stereotypy forms and sequences. Although the two species did not differ in overall frequency, the stereotypies of sun bears appeared to be more food‐motivated than those of Asiatic black bears: the sun bears displayed a higher frequency and diversity of oral stereotypies, and higher levels of pre‐feeding stereotypy, and performed significantly more of their total stereotypies in locations from which they could view food arrival. This study demonstrates how analyzing stereotypies in detail can help identify the motivations that underlie these behaviors, and potentially reveal their degree of establishment–both of which are important factors in stereotypy treatment. Zoo Biol 23:409–430, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
75.
Chamakou AC Dede E Moutafi A Thanopoulos V Chryssanthopoulos S Loukopoulou S Pitsavos C Stefanadis C Davos CH 《Cytokine》2012,57(1):130-135
Introduction
Inflammation and neurohormonal activation are considered to be involved in the development of earlier and/or later complications in congenital heart disease patients, even after a successful repair of the lesion. It is not yet clarified what is the role of the therapeutic interventions in the occurrence of such a response and how it could be associated with possible postoperative complications.Aim
We sought to assess the inflammatory and neurohormonal response to transcatheter closure of secundum type atrial septal defects (ASD) over a six-month follow-up period. We also evaluated the association between the respective markers and catheterization data as well as echocardiographic measurements.Methods
Plasma concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), N-terminal-proatrial natriuretic peptide (NT-proANP) and N-terminal-probrain natriuretic peptide (NT-proBNP) were assessed and echocardiographic measurements were performed in twenty-eight patients with atrial septal defect prior to, and at the first, second and sixth months post transcatheter closure. Thirty-three age-matched healthy volunteers were also enrolled.Results
IL-6 plasma levels, although higher preoperatively, [physical logarithm (ln) IL-6: 3.37 ± 0.66 vs 2.92 ± 0.44 pg/ml, p = 0.015], reached control levels postoperatively, at the end of the third month, whereas TNF-α and IL-10 were not influenced by the procedure. NT-proANP levels were elevated preoperatively compared to the control group (ln NT-proANP 3.78 ± 0.572 vs 3.48 ± 0.30, p = 0.031), with a further significant increase during the 1st month (ln NT-proANP 3.78 ± 0.572 vs 4.2 ± 0.42, p = 0.006), following the pattern of the left atrial volume enlargement, and remained high even 6 months after the procedure .On the other hand, the initially normal concentrations of NT-proBNP, after a transient significant increase during the first month postoperatively (ln NT-proBNP 3.56 ± 0.94 vs 4.58 ± 0.91, p < 0.0001) returned to the controls’ levels at the end of the third month. Preoperative concentrations of NT-proANP positively correlated with NT-proBNP concentrations and pulmonary to systemic flow ratio (Qp/Qs).Conclusions
Transcatheter closure could improve, on a mid- term basis, the inflammatory process but natriuretic peptides’ secretion continues in parallel with left atrial volume increase. Further follow up is required to determine the long-term progress of the inflammatory and neurohormonal response to the procedure. 相似文献76.
77.
78.
目的应用心内电生理技术研究心房快速起搏(RAP)对兔心房单向动作电位(MAP)的影响。方法成年新西兰兔20只随机分为二组:假手术组、模型组各10只。经颈内静脉将电极置入右心房。以600次/分行RAP,同时分析在0、4、8、12和24h的单向动作电位时程(MAPD)。结果假手术组在实验的时间段内右房游离壁MAP复极90%时程(MAPD90)无明显差别。RAP8h,起搏组右房游离壁MAPD90较P0有明显缩短,从起搏前(112.50±9.57)ms至起搏8h分别缩短到(51.25±4.79)ms,分别缩短了61.25ms。结论房颤(AF)时心房MAPD90缩短。MAP技术可安全地用于研究AF时的电重构(ER),能提供准确的电生理改变的信息。 相似文献
79.
80.
Claudia Seyler Patrick A. SchweizerEdgar Zitron Hugo A. KatusDierk Thomas 《Biochemical and biophysical research communications》2014
Atrial fibrillation (AF) contributes significantly to cardiovascular morbidity and mortality. The growing epidemic is associated with cardiac repolarization abnormalities and requires the development of more effective antiarrhythmic strategies. Two-pore-domain K+ channels stabilize the resting membrane potential and repolarize action potentials. Recently discovered K2P17.1 channels are expressed in human atrium and represent potential targets for AF therapy. However, cardiac electropharmacology of K2P17.1 channels remains to be investigated. This study was designed to elucidate human K2P17.1 regulation by antiarrhythmic drugs. 相似文献