急性心肌梗塞早期溶栓治疗前后QT间期离散度变化

探讨急性心肌梗塞溶栓治疗前后QT间期离散度 (QTintervaldispersion ,QTd)的变化 ,我们将 34例施溶栓治疗的急性心肌梗塞 (acutemyocardialinfarction ,AMI)病人分为 2组 :再通组 18例 ,未通组 16例。测定溶栓前及溶栓后 2、8、2 4、4 8h和 1周的同步 12导联心电图QTd。溶栓前再通组与未通组QTd分别为 :58.3± 13.5ms ,56.2± 17.1ms ;溶栓后再通组与未通组QTd分别为 :2h ,70 .2± 14.2ms ,58.5± 13.1ms ;8h ,51.2± 13.6ms ,73.4± 15.8ms ;2 4h ,4 8.7± 16.8ms,66.5± 15.2ms ;4 8h ,4 0 .5± 11.8,66.5± 15.2 ;1周 ,38.6± 13.4 ,50 .1± 15.8。溶栓后 ,再通组与未通组QTd各对应时间段相比 ,有显著性差异 (P <0 .0 1)。溶栓前再通组与未通组QTd相比无显著性差异 (P >0 .0 5)。说明成功的溶栓治疗使心室复极的QTd缩短 ,使QTd最高值提前出现。QTd缩短速度明显加快 ,对于判断溶栓治疗的疗效有一定意义     

倍他乐克对心绞痛患者QT间期离散度的影响

目的研究倍他乐克对冠心病劳力型心绞痛患者QT间期离散度(QTd)的影响。方法按照前瞻性研究设计,对162例入选患者进行随机、单盲试验研究,入选患者在治疗前做12导联同步心电图检查,测量心率、最大和最小QT间期,计算QTd、心率校正后QT间期离散度和QT间期离散度比,在治疗4周后重复上述心电图检查;治疗组服用倍他乐克50～100 mg/d,对照组服用安慰剂治疗,比较2组前后的QTd变化,用t检验进行统计学处理。结果倍他乐克可以明显缩短劳力性心绞痛患者的QTd和心率校正后QTd(QTcd),降低QT间期离散度比。比较两组治疗4周后的QTd、QTcd和QTd ratio数值,两组差异有统计学意义,QTd、QTcd和QT间期离散度比分别为(44.5±17.3)ms比(63.8±15.6)ms,P<0.01,(45.7±15.3)ms比(64.9±16.3)ms,P<0.01和4.94%±2.1%比8.08%±1.5%,P<0.001。结论倍他乐克在改善心肌缺血的同时可以明显的缩短QTd,降低QT间期离散度比;QT间期离散度比对预测冠心病患者发生恶性心律失常和猝死比QTd具有更重要的预后价值。     

高血压左心室肥厚患者心电图QT离散度改变

目的　探讨原发性高血压左心室肥厚患者心电图QT离散度 (简称QTd)变化。　方法　用美国超九 ATL(XO16 3)彩色多谱勒诊断仪二维超声测量其舒张期左心室室间隔厚度和左心室后壁厚度 ,以≥ 1 2cm作为左心室肥厚诊断标准 ,对高血压左心室肥厚组 (n =36 ,男 女 =2 0 16例 ,平均年龄 6 0岁± 12岁 )、高血压左心室非肥厚组(n =5 0 ,男 女 =30 2 0例 ,平均年龄 6 2岁± 12岁 )进行测量 ,再用心电图ECG 8110P( 0 180 8A3)描记其常规 12导联心电图 ,手工测量其最大QT间期 (QTmax)、最小QT间期 (QTmin)和心动周期RR间期 ,计算QTd和心率校正的QTcd ,并随机匹配正常人群组 (n =4 0 ,男 女 =2 4 16例 ,平均年龄 5 8岁± 13岁 )。　结果　高血压左心室肥厚组QTd为6 0ms± 17ms ,QTcd为 6 8ms± 2 4ms,高血压左心室非肥厚组QTd为 4 1ms± 13ms,QTcd为 4 3ms± 17ms ,正常人群组QTd为 4 3ms± 11ms ,QTcd为 4 4ms± 16ms,前两组比较有显著性差异 ,P <0 0 1,后两组比较无显著性差异 ,P >0 0 5。　结论　原发性高血压左心室肥厚患者QT间期离散度增大。     

QT离散度与高血压合并Ⅱ型糖尿病的关系探讨

目的　探讨QT离散度 (QTd)与高血压 (EH)合并Ⅱ型糖尿病 (NIDDM)的关系。方法　测量 5 2例EH合并NIDDM(A组 )和 5 2例EH无并发症患者 (B组 )以及 5 0例正常人 (C组 )的同步 12导联心电图及其最大Q -T间期 (QTmax) ,最小Q -T间期 (QTmin) ,QTd =QTmax -QTmin。用Bazett公式计算校正的QTd(QTcd) ,进行比较分析。结果　QTd、QTcd :A组分别为 (5 5 8± 13 2 )ms和 (63 8± 13 6)ms;B组分别为 (40 6± 8 4)ms和 (46 1± 10 0 )ms;C组分别为 (40 0± 9 7)ms和 (44 1± 10 9)ms。A组与B组、A组与C组比较有非常显著的统计学意义 (P <0 0 1)。结论　QTd、QTcd与高血压合并Ⅱ型糖尿病密切相关 ,可作为预测其心血管受损程度的敏感指标     

急性心肌梗死QT离散度的临床意义探讨

目的 观察急性心肌梗死(AMI)QT离散度(QTd)的变化与心律失常的关系以及有效的溶栓治疗对QTd的影响.方法 AMI病人42例与正常健康者50例进行对比,所有对象测量12导联心电图不同导联最长与最短的QT间期Qtmax和Qtmin,QTd=Qtmax-Qtmin,根据Bazett's公式,校正QT间期QTc=QT/(√RR),校正QT离散度(QTcd)=Qtcmax-Qtcmin.结果 AMI病人QTd、QTcd分别为(68.7±16.3)、(74.8±20.1)ms,对照组QTd(32.3±11.4)ms、QTcd(36.4±13.3)ms,P＜0.01,有心律失常组QTd(70.4±19.5)ms、QTcd (79.4±22.5)ms,无心律失常组QTd(54.4±16.3)ms、QTcd(63.2±20.1)ms,P＜0.01.溶栓有效者与无效者比较差异也有统计学意义(P＜0.05,表1).结论 有效的溶栓治疗可使QTd明显减小,减少危险性心律失常的发生,降低AMI患者病死率.QTd对预测AMI患者溶栓疗效以及早期危险性心律失常和预后具有重要价值.     

依那普利对高血压病左心室肥厚患者QT离散度的影响

目的　研究长期使用依那普利治疗高血压病合并左心室肥厚时对QT离散度的影响。方法　 2 4例高血压病 (EH)合并左心室肥厚 (LVH)者 ,服用依那普利 (10mg 1次 /d) 3年 ,用标准 12导联心电图测量QT间期、校正的QT间期 (QTc)、QT间期离散度 (QTd)及校正的QT间期离散度 (QTcd) ;用二维及M型超声心动测定有关心血管参数。结果　依那普利不仅能迅速降压 ,而且能逐渐降低左心室重量指数 (LVMI)达 3 9% (P <0 .0 0 1) ,显著提高左心室泵血功能 ;同时明显缩短QTd[从 (61± 2 1)到 (41± 15 )ms、QTcd从 (67± 2 7)到 (46± 18)ms] ,QT及QTc也同样明显缩短。结论　长期用依那普利治疗EH合并LVH ,能明显使患者左心室肥厚回缩 ,提高其左心室收缩功能 ,并通过降低QTd及QTcd ,进一步降低室性心律失常发生率 ,从而改善预后。     

急性心肌梗死QT离散度的临床意义探讨

目的观察急性心肌梗死(AMI)QT离散度(QTd)的变化与心律失常的关系以及有效的溶栓治疗对QTd的影响。方法AMI病人42例与正常健康者50例进行对比,所有对象测量12导联心电图不同导联最长与最短的QT间期QTmax和QTmin,QTd=QTmax-QTmin,根据Bazett’s公式,校正QT间期QTc=QT/RR,校正QT离散度(QTcd)=QTcmax-QTcmin。结果AMI病人QTd、QTcd分别为(68.7±16.3)、(74.8±20.1)ms,对照组QTd(32.3±11.4)ms、QTcd(36.4±13.3)ms,P<0.01,有心律失常组QTd(70.4±19.5)ms、QTcd(79.4±22.5)ms,无心律失常组QTd(54.4±16.3)ms、QTcd(63.2±20.1)ms,P<0.01。溶栓有效者与无效者比较差异也有统计学意义(P<0.05,表1)。结论有效的溶栓治疗可使QTd明显减小,减少危险性心律失常的发生,降低AMI患者病死率。QTd对预测AMI患者溶栓疗效以及早期危险性心律失常和预后具有重要价值。     

冠状动脉内支架置入术对有与无心肌梗死史患者QT离散度影响的比较

探讨和比较冠心病患者经过成功冠状动脉 (简称冠脉 )内支架置入术对有与无心肌梗死史的病人QT离散度(QTd)影响的程度 ,选择术前QTd≥ 60ms者 1 0 0例 ,根据有无心肌梗死病史分为两组 ,其中无心肌梗死组 62例 ,心肌梗死组 38例 ,于术前、后 72h分别做 1 2导联同步心电图进行测量QTd和计算校正QTd(QTcd)。在无心肌梗死组中 ,支架置入术后 ,QTd、QTcd明显缩短 (分别为 51± 1 9vs 72± 34ms,54± 2 4vs 81± 37ms;P <0 .0 5) ;而在心肌梗死史组中 ,术后QTd、QTcd上无显著变化 (分别为 70± 2 6vs74± 30ms ,80± 30vs82± 32ms;P >0 .0 5)。结论 :冠脉内支架置入术显著缩短无心肌梗死史冠心病患者的QTd和QTcd ,而对有心肌梗死冠心病患者的QTd和QTcd无影响     

心室偏心性除极时复极离散度指标的应用

目的　评价显性预激综合征时心室复极离散度指标 ( QTd和 JTd)的临床价值 ,以阐明偏心性心室除极是否导致心室复极离散度异常。方法　选择 4 6例成人显性预激综合征患者行射频消融术 ,观察射频消融前后的心室复极离散度指标 ( QTd和 JTd)的变化。结果　射频消融后最大 QRS时间较消融前缩短 ( 4 6± 2 8) ms,随着预激波消失和 QRS的“正常化”,消融后的 QTd[( 3 0± 13 ) ms]和 QTcd[( 3 7± 19) ms]较消融前的 QTd[( 5 1± 2 3 ) ms]和 QTcd[( 60± 2 7) ms]明显缩短( P值均 <0 .0 5 ) ,而消融后的 JTd[( 2 5± 10 ) ms]和 JTcd[( 2 8± 10 ) ms]与消融前的 JTd[( 2 7± 12 )ms]和 JTcd[( 3 2± 12 ) ms]相比无明显变化 ( P值均 >0 .0 5 )。消融前的预激 QRS波群导致消融前后 QTd和 QTcd的差别。由于消融前后 JTd和 JTcd并无差异 ,表明心室偏心除极不导致复极离散度异常。结论　在显性预激存在时 ,测定心室复极离散度使用 JTd和 JTcd优于 QTd和 QTcd;同时 ,预激时的心室偏心除极不导致复极离散度异常 ,即心室偏心除极不是导致复极离散度异常的机制。     

缬沙坦对急性心肌梗死患者早期QT间期离散度的影响

通过研究缬沙坦对急性心肌梗死 (AMI)患者早期QT间期离散度 (QTd)的影响 ,探讨缬沙坦对缺血心肌的保护作用。将 34例AMI患者随机分成缬沙坦 +基础治疗组 (治疗组 ,A组 ,17例 )和基础治疗组 (对照组 ,B组 ,17例 )。另设正常人 2 0例作对照组 (正常对照组 ,C组 )。在服药前、服药后 3,7天分别测量QTd及校正的QTd(QTcd) ,并观察服药前及服药 3天后室性心律失常的发生率。结果 :AMI患者的QTd及QTcd较正常人明显延长 (75 .9± 11.9vs 32 .7± 12 .6ms ,85 .5± 12 .8vs 36 .5± 13.2ms,P均 <0 .0 1) ;AMI患者中发生室性心律失常者 (19例 )的QTd及QTcd则较非室性心律失常者 (15例 )明显增加 (81.1± 11.1vs 6 9.3± 9.6ms,92 .0± 10 .5vs 73.6± 18.9ms ,P均 <0 .0 1) ;服药 7天后A组和B组的QTd及QTcd均明显减少 ,但A组比B组减少的更为显著 (41.5± 11.1vs 5 7.9± 10 .8ms,4 6 .9± 12 .3vs 6 5 .5± 12 .5ms ,P均 <0 .0 1) ;服药 3天后A组的QTd及QTcd较服药前也有明显的减少 ;服药 3天后A组中发生室性心律失常者 (2例 )明显减少 ,与治疗前 (10例 )有显著性差异 (P <0 .0 5 )。结论 :AMI患者早期QTd及QTcd较正常人增大 ,并且伴有室性心律失常的患者QTd及QTcd增大更为显著 ,AMI患者早期服用缬沙坦可降低QTd及     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Variabilité des concentrations plasmatiques de l’angiotensinogène et risque d’hypertension artérielle chez le rat transgénique

Aim

Genetic polymorphisms of the human angiotensinogen gene are frequent and may induce up to 30% increase of plasma angiotensinogen concentrations with a blood pressure increase of up to 5 mmHg. Their role for the pathogenesis of human arterial hypertension remains unclear. High plasma angiotensinogen levels could increase the sensitivity to other blood pressure stressors.

Methods

Male transgenic rats with a 9-fold increase of plasma angiotensinogen concentrations and male non-transgenic rats aged 10 weeks were treated or not with NG-Nitro-L-arginine-methyl ester for 3 weeks in their drinking water (n = 3/group). Systolic blood pressure and body weight were measured at baseline and at the end of the study when left ventricular weight and ventricular expression of angiotensin I-converting enzyme and procollagen Iα1 were determined (polymerase chain reaction).

Results

At baseline, transgenic rats had +18 mmHg higher bood pressure and –8% lower body weight compared to non-transgenic rats (P < 0.05) without significant changes for the vehicle groups throughout the study (P > 0.05). NG-Nitro-L-arginine-methyl ester increased blood pressure, left ventricular weight and left ventricular weight indexed for body weight by +41%, +17.6% and +18.6% (P < 0.05) in transgenic and +25%, +5.3% and +6.7% (P > 0.05) in non-transgenic rats compared to untreated animals, respectively. Cardiac gene expression showed no differences between groups (P > 0.05).

Conclusion

Increased plasma angiotensinogen levels may sensitize to additional blood pressure stressors. Our preliminary results point towards an independent role of angiotensinogen in the pathogenesis of human hypertension and associated end-organ damage.