Acute Hyperthermia Syndromes

A high core body temperature is a medical emergency. Neuronal mitochondria and plasma membranes are thought to undergo protein changes at temperatures higher than 40°C, which lead to brain damage or dysfunction. In addition, the effects of hyperthermia on an already injured brain cause further injury. Control of fever is one of the important additional interventions necessary to control increased intracranial pressure and status epilepticus and to treat hypertensive surges in patients with sympathetic system overdrive.

The Bezold-Jarisch Reflex and The Inflammatory Response Modulation in Unanesthetized Endotoxemic Rats

Evidence indicates that the activation of the parasympathetic branch of the autonomic nervous system may be effective in treating inflammatory diseases. Previously, we have described that baroreflex activation displays anti-inflammatory properties. Analogous to the baroreflex, the Bezold-Jarisch reflex also promotes parasympathetic activation with simultaneous inhibition of the sympathetic system. Thus, the present study aimed to evaluate whether the activation of the Bezold-Jarisch reflex would also have the ability to reduce inflammation in unanesthetized rats. We used lipopolysaccharide (LPS) injection (5mg/kg, i.p.) to induce systemic inflammation in male Wistar Hannover rats and phenylbiguanide (PBG) administration (5μg/kg, i.v.) to activate the Bezold-Jarisch reflex. Spleen, heart, hypothalamus, and blood samples were collected to determine the levels of cytokines. Compared to baseline, PBG reduced the arterial pressure (115±2 vs. 88±5mmHg) and heart rate (380±7 vs. 114±26bpm), immediately after its administration, confirming the activation of the parasympathetic system and inhibition of the sympathetic system. From the immunological point of view, the activation of the Bezold-Jarisch reflex decreased the plasma levels of TNF (LPS: 775±209 vs. PBG + LPS: 248±30pg/ml) and IL-6 levels in the spleen (LPS: 39±6 vs. PBG + LPS: 24±4pg/mg of tissue). However, it did not change the other cytokines in the plasma or the other tissues evaluated. These findings confirm that the activation of the Bezold-Jarisch reflex can modulate inflammation and support the understanding that the cardiovascular reflexes regulate the immune system.

Analysis of cardiac rhythm variability in Jersey breed cows with different vegetative status

Purpose: Conduct an analysis of cardiac rhythm variability in the cows of the Jersey breed with a different vegetative status.Materials and methods. Indicators of the electrocardiogram (ECG) and cardiac rhythm variability studied on cows of the Jersey breed (n = 103). For the analysis and removal of ECG, the animal studied used the program «Conan-4.5» in the system of frontal administrations according to the method of P. M. Roshchensky. Clinical research methods were carried out according to the methods of clinical inspection of animals B. V. Ears and included — inspection, palpation, percussion and auscultation of the heart area.Results. Among the entire studied array of animals, the largest amount was sympathyone — 50,5%, normotonics — 24,3%, hypersympathicotonics — 16,5%. The smallest amount — vagotonic — 8,7%. For the vagotonic, the respiratory modulation index was 8,16±0,02%, the index of the sympathetic system is 43±0,1%, and the index of slowly wave arrhythmia is 0,8±0,1%. This group of cows parasympathetic (software) prevails over the sympathetic department of the vegetative nervous system. For normotonics, the value of the respiratory modulation index was 4,14±0,03%, the index of the sympathetic system is 96±0,2%, and im is 2,5±0,2%. This group is characterized by an equilibrium state between sympathetic department and VNS. The ids for sympathicotonists amounted to 2,78±0,03%, the index of the sympathetic system is 195±0,2%, and im is 8,2±0,1%. At sympathicotonists, which are characterized by a predominance with VNS above software. The hyper smpathetical respiratory modulation index was 1,34±0,02%, ICAS — 588±0,1%, and im is 11,4±0,3%. In hypersympathicotonists, which are characterized by the predominance of the super-viper vehicle of the vegetative nervous system over parasympathetic.Conclusion. The separation of the entire array on the subgroups based on the vegetative status of animals was based on the indicators of the voltage index of regulatory systems. To confirm the correctness of the separation of the studied array of animals on the subgroup, statistical processing was carried out and a classification matrix was built. Also, to confirm the classification separation matrix, additional statistical processing of the material of the differences between the obtained groups in the square of the distance of the Mahalonobis D2 was carried out. In the course of further registration and mathematical analysis of the variability of the heart rate of cattle (cows of the Jersey breed) with the help of a modern complex electrophysiological laboratory «Conan-4.5» features of indexes of A. Ya. Kaplan were established.

Is There Any Sympathetic Skin Response (SSR) Abnormality in Raynaud Phenomenon?

Objectives: Sympathetic skin response (SSR) is a technique for assessment of the damage of peripheral neuropathies and the disorders of the sympathetic system. This study aimed to evaluate SSR among patients with Raynaud phenomenon (RP). Methods: Between January 1, 2015 and December 30, 2018, about 20 patients with RP and 20 healthy subjects as the control group were recruited from patients referring to the Outpatient Clinics of Shiraz medical University. All the participants were clinically examined, and the SSR was performed using a standard protocol. SSR is abnormal when the latency is prolonged and/or the amplitude reduced. Results: Raynaud's group consisted of 19 women (95 %) and 1 male (5%). 3 patients (15 %) with primary Raynaud's phenomenon (PRP) and 17 patients (85%) with secondary Raynaud's phenomenon (SRP). The control group consisted of 16 women (80%) and 4 males (20%). The mean age of the Raynaud's group and control subjects was 43.1±9 and 36.7±8.6 years, respectively. The SSR to the electrical stimulus was absent in 3 patients (PRP patients). The total median nerve mean latencies in the upper limb were 1.9±0.57 and 1.19±0.52 seconds for the Raynaud's group and control groups, respectively (p <0.001). These findings revealed significantly prolonged SSR latencies in the Raynaud's group, while the mean amplitude showed no significant differences in both groups (p =0.756). Conclusion: Absence or prolonged latency of SSR was associated with the disorders of the unmyelinated axons in the sympathetic system. Our findings suggested the disorders of unmyelinated axons in Raynaud's phenomenon. Keywords: Raynaud Disease; Autonomic Nervous System; Electrodiagnosis; Sympathetic Fibers; Nerve Conduction.

Maturation of the cardiac autonomic regulation system, as function of gestational age in a cohort of low risk preterm infants born between 28 and 32 weeks of gestation

Objectives The maturation of the sympathetic nervous system (SNS) occurs steadily throughout gestation while the myelinated vagus has accelerated maturation periods, between 25 and 32 weeks of gestation and a further increase around 37–38 weeks of gestation. The aim was to quantify the cardiac autonomic regulation maturation, as a function of gestational age (GA) in a cohort of low risk preterm infants born between 28 and 32 weeks of gestation by assessing heart rate variability (HRV) at week 32, and at week 35 postmenstrual age (PMA). Methods Forty preterm infants were recruited, 24 h recordings of breathing rate and RR intervals were obtained at week 32 and week 35 PMA. Results A significant difference was noted between preterm infants born before 32 weeks GA and preterm infants born at week 32; the latter present higher HRV values throughout the follow-up period. No significant change over time was noted for the parasympathetic HRV measures while a significant increase was found in the sympathetic system. Moreover, a significant interaction effect of time and system was found, the increase in values of the sympathetic system over time was significantly larger than the change noted in the vagal HRV measures. Conclusion Given the beneficial influence of vagal tone on health and developmental outcomes in preterm infants, the findings of the current study highlight the need for further studies on the impact of specifics gestational age on vagal development and later assessing interventions associate with its continue development and maturation at these specific periods.

Plasma metanephrins are associated with myocardial hypertrophy and cardiac diastolic function in patients with essential hypertension

Purpose: To explore the association between the sympathetic system activity and myocardial hypertrophy in patients with essential hypertension. Methods: A total of 84 essential hypertension inpatients were recruited from China-Japan Friendship Hospital between January 2019 and September 2019. Activity of sympathetic system was quantified by plasma metanephrines (MNs) levels. All subjects received an echocardiographic test. Results: The interventricular septum thickness (diastolic), left ventricular mass and left ventricular mass index increased significantly with plasma MNs quartiles, and plasma MNs were positively and significantly correlated with early diastolic transmitral flow velocity to early diastolic mitral annular tissue velocity. Conclusions: In patients with essential hypertension, high level of plasma MNs associates with left ventricular hypertrophy and impaired diastolic function.