Structural Doubleness and Repetition

Chapter 2, treating comic doubleness as a structural matter, explores the way scenes, actions, and plot lines reflect each other, as if to create an uncanny closed circuit or dream-world. Those reflections call up a long-standing critical recognition of ‘magical parallelisms,’ such as between the story lines of Viola and Sebastian, that express the Renaissance fascination with analogy and with occult theories of sympathetic influence. Within the play, structural doublings create affects ranging from enervation and frustrated desires, to a premonition of fatedness and converging destinies, to the agitation of manically accelerated action, to the liberating recognition of differences with in repetitions. Focusing on Twelfth Night, this chapter considers how the play creates the sense of a numinous but opaque providentialism, features that it also finds in other Shakespearean, Italian, and Tudor plays, including those of John Lyly.

Trophic sympathetic influence weakens pro-contractile role of Cl− channels in rat arteries during postnatal maturation

Membrane transporters and their functional contribution in vasculature change during early postnatal development. Here we tested the hypothesis that the contribution of Cl− channels to arterial contraction declines during early postnatal development and this decline is associated with the trophic sympathetic influence. Endothelium‐denuded saphenous arteries from 1- to 2-week-old and 2- to 3-month-old male rats were used. Arterial contraction was assessed in the isometric myograph, in some experiments combined with measurements of membrane potential. mRNA and protein levels were determined by qPCR and Western blot. Sympathectomy was performed by treatment with guanethidine from the first postnatal day until 8–9-week age. Cl− substitution in the solution as well as Cl−-channel blockers (MONNA, DIDS) had larger suppressive effect on the methoxamine-induced arterial contraction and methoxamine-induced depolarization of smooth muscle cells in 1- to 2-week-old compared to 2- to 3-month-old rats. Vasculature of younger group demonstrated elevated expression levels of TMEM16A and bestrophin 3. Chronic sympathectomy increased Cl− contribution to arterial contraction in 2-month-old rats that was associated with an increased TMEM16A expression level. Our study demonstrates that contribution of Cl− channels to agonist-induced arterial contraction and depolarization decreases during postnatal development. This postnatal decline is associated with sympathetic nerves development.

Effect of Amiodarone, Sotalol and Bisoprolol on Heart Rate Variability in Patients with Atrial Fibrillation

Aim. To study the effect of class III antiarrhythmic drugs (amiodarone and sotalol), and the β-blocker bisoprolol on the spectral parameters of heart rate variability in patients with different forms of atrial fibrillation (AF).Material and methods. Spectral analysis of heart rate variability of 5-minute electrocardiography intervals was used. The study included patients with newly diagnosed AF and having a duration of the disease from 6 months to 8 years. Arterial hypertension, coronary artery disease, myocardial infarction (in history), conduction disorders and type 2 diabetes mellitus were diagnosed as comorbidities. The following parameters were calculated: the total power (TP) of the spectrum, the power of very low frequencies (VLF), low frequencies (LF) and high frequencies (HF).Results. In the group of patients with newly diagnosed AF without concomitant diseases after administration of amiodarone, VLF prevails in the spectrum structure, which indicates a significant role of humoral factors in the regulation of heart rate. The power of LF, reflecting the activity of the sympathetic nervous system, prevails over HF power after administration of amiodarone. In patients with newly diagnosed AF, having concomitant diseases, sympathetic influences prevail over parasympathetic ones by 3.6 times after administration of amiodarone. In the group of patients who have reduced the number of comorbidities, the LF/HF decreases and is only 1.66 after administration of amiodarone. The decrease in the number of negative factors is also accompanied by an increase in the influence of the vagus nerve on the activity of the heart. In the study of the effects of sotalol, the LF/HF in this group was twice lower in the group of patients with long-term AF. In patients receiving bisoprolol as antiarrhythmic therapy, the proportion of LF in the group of patients with newly diagnosed AF is 2 times lower, and the proportion of HF is twice higher than in the group of patients with long-term AF.Conclusion. The effect of antiarrhythmic drugs on the spectral parameters of heart rate variability depends on the duration AF. The presence of concomitant diseases of the cardiovascular system can significantly change the effect of antiarrhythmic drugs on the spectral parameters of heart rate variability and is accompanied by an increase in sympathetic activity. In patients with newly diagnosed AF, amiodarone and sotalol cause a similar effect – the predominance of sympathetic influence; when using bisoprolol, the predominant influence belongs to the vagus nerve. In patients with long-term AF, the opposite effect of drugs is observed: the use of amiodarone is accompanied by a more pronounced influence of the vagus nerve, and bisoprolol – the predominance of sympathetic influence. When using sotalol, sympathetic influences also prevail, more pronounced in patients with newly diagnosed AF.

Electrocardiographic interpretation of the nasopharyngealresponse in conscious rabbits

The present study was conducted to recognize by part, the cardiovascular events of the nasopharyngeal reflex, through electrocardiographic interpretations. ECG patterns were traced in twelve clinically normal and healthy New Zealand White rabbits of both sexes, weighing between 2-3 kg and aged between 1-3 years with inhalant irritants. Immediately after induction of formaldehyde vapour, the heart rate fell by 69% from a mean of 192 ± 7.310 bpm to 60 ± 1.296 bpm, whereas exposure with cigarette smoke caused a fall in heart rate by 74% from a mean of 205 ± 9.605 bpm to 53 ± 3.065 bpm. With both irritants, P wave becomes smaller and totally disappeared, indicating an increased vagal activity inducing a sinoatrial node arrest. The amplitude of QRS complex also significantly decreased; and so did the duration of P wave and PR interval, presumably due to junctional escape. T wave duration decreased with slow ventricular repolarization. Bradycardia was also evident with increased QT interval. However, there was no change in QRS complex or ventricular depolarization, mediated perhaps via compensatory sympathetic influence on the ventricular myocardium. The study demonstrates that both formaldehyde and cigarette smoke provoked a similar protective response of rabbits against noxious fumes.

Autonomic regulaton in chldren of older school age with a different level of anxiety

The state of the autonomic nervous system with the use of the technique of a 5-minute registration of ECG has been studied in 57 children of older school age with low, median and high anxiety. It has been established that with low anxiety a vegetative balance is provided at the expense of the parasympathetic nervous system. The role of the suprasegmental portions of the autonomic nervous system (ANS) increases sympathetic influence enhances with medianxiety. A transformation of the regulation of the heart rate into the humoral-metabolic one, a depletion of the adaptive system and a reduction of the functional condition of the organism are marked in girls with the high level of anxiety.

Spontaneous fluctuations in the peripheral photoplethysmographic waveform: roles of arterial pressure and muscle sympathetic nerve activity

Assessment of spontaneous slow waves in the peripheral blood volume using the photoplethysmogram (PPG) has shown potential clinical value, but the physiological correlates of these fluctuations have not been fully elucidated. This study addressed the contribution of arterial pressure and muscle sympathetic nerve activity (MSNA) in beat-to-beat PPG variability in resting humans under spontaneous breathing conditions. Peripheral PPG waveforms were measured from the fingertip, earlobe, and toe in young and healthy individuals ( n = 13), together with the arterial pressure waveform, electrocardiogram, respiration, and direct measurement of MSNA by microneurography. Cross-spectral coherence analysis revealed that among the PPG waveforms, low-frequency fluctuations (0.04–0.15 Hz) in the ear PPG had the highest coherence with arterial pressure (0.71 ± 0.15) and MSNA (0.44 ± 0.18, with a peak of 0.71 ± 0.16 at 0.10 ± 0.03 Hz). The normalized midfrequency powers (0.08–0.15 Hz), with an emphasis on the 0.1-Hz region, were positively correlated between MSNA and the ear PPG ( r = 0.77, P = 0.002). Finger and toe PPGs had lower coherence with arterial pressure (0.35 ± 0.10 and 0.30 ± 0.11, respectively) and MSNA (0.33 ± 0.10 and 0.26 ± 0.10, respectively) in the LF band but displayed higher coherence between themselves (0.54 ± 0.09) compared with the ear ( P < 0.001), which may suggest the dominance of regional vasomotor activities and a common sympathetic influence in the glabrous skin. These findings highlight the differential mechanisms governing PPG waveform fluctuations across different body sites. Spontaneous PPG variability in the ear includes a major contribution from arterial pressure and MSNA, which may provide a rationale for its clinical utility.