Ventricle In Man Research Articles

Plasma aryl hydrocarbon receptor associated with epicardial adipose tissue in men: a cross-sectional study

BackgroundEpicardial adipose tissue (EAT) is a type of ectopic fat with endocrine and paracrine functions. Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that responds to environmental stimuli. AhR expression is associated with obesity. In this cross-sectional study, we aimed to determine the relationship between circulating AhR concentrations and EAT.MethodsA total of 30 men with obesity and 23 age-matched men as healthy controls were enrolled. Plasma AhR concentrations were determined at fasting. The EAT thickness was measured on the free wall of the right ventricle from the basal short-axis plane by magnetic resonance imaging.ResultsThe participants with obesity had a higher plasma AhR level than the controls (81.0 ± 24.5 vs. 65.1 ± 16.4 pg/mL, P = 0.010). The plasma AhR level was positively correlated with EAT thickness (correlation coefficient = 0.380, P = 0.005). After adjusting for fasting glucose levels, plasma AhR levels were still significantly associated with EAT thickness (95% CI 0.458‒5.357, P = 0.021) but not with body mass index (P = 0.168).ConclusionPlasma AhR concentrations were positively correlated with EAT thickness on the free wall of the right ventricle in men. Further investigations are needed to evaluate the causal effects and underlying mechanisms between AhR and EAT.

Low‐dose Lithium is Associated with Left Ventricular Ejection Fraction in Healthy Young Men but not Women

The impact of lithium (Li) exposure on the cardiovascular system is perplexing, as beneficial, negative, and null effects have been identified. Li is an inhibitor of glycogen‐synthase kinase 3β (GSK3‐β) which has been identified as a possible therapeutic target for cardiovascular disease (CVD) and mental health disorders. While earlier ecological studies suggest that trace amounts of Li may protect against CVD, no study to date has investigated the effects of low‐dose Li exposure on cardiac structure and function in healthy young adults without CVD and whether these associations are sex dependent. The purpose of the present investigation was to examine the association between Li exposure and left ventricular mass (LVM) and function in healthy young adults. This investigation represents a cross‐sectional analysis of the Niagara Longitudinal Heart Study (NLHS) at the midpoint of data collection for 156 participants aged 19 – 25 years. A final sample size of 117 had both valid Li and left ventricular data upon analyses. LVM was indexed to height2.7 (LVMi), ejection fraction (EF), fractional shortening (FS), and stroke volume (SV) were assessed following echocardiography in the parasternal long‐axis view of the left ventricle. Serum Li levels were measured using inductively‐coupled plasma mass spectrometry. Li concentration was significantly associated with EF (r = −0.183, p = 0.05) and ESV (r = 0.197, p = 0.03) among the total sample. Li concentration did not differ when examined by sex (p > 0.05), however LVMi, ESV, EDV, SV, and EF were all significantly higher in males than females (p < 0.05). Li was only significantly correlated with EF in men (r = −0.320, p = 0.02) however no correlation was observed among women (p > 0.05). The novel result of our investigation was naturally occurring concentration of Li is associated with decreased EF in men, but not women, although, there was no significant difference in SV. Further, there was no effect of low‐dose Li on LVMi. This is in contrast to some animal studies which demonstrate long‐term exposure to Li has potent hypertrophic effect on the left ventricle, although, Li concentrations in our sample were considerably lower and fall within a normal physiological range. These findings may result from differential sensitivities of the GSK‐3β receptor to Li in the left ventricle in men and women, although further investigation is required.Support or Funding InformationThis research project is funded by the Canadian Institutes of Health Research (CIHR #s 363774, 399332). KSD is funded by a CIHR Doctoral Research Award – Frederick Banting and Charles Best Canada Graduate Scholarship (RFN#167014). VAF is supported by a Brock Explore Grant and an NSERC Discovery Grant (2019‐05833).

Кореляційні зв’язки між окремими структурами лікворної системи

Introduction into medical practice of new methods of neuroimaging — computer and magnetic resonance tomography, changed principles of diagnosis of brain morphological changes and opened new horizons in the study of its structure. The aim of our study was to evaluate morphometric parameters of ventricular system of the brain on the results of MRI of elderly persons (females of 56-74 years, males 61-74 years). Object and methods. A survey was conducted in the department of radiation diagnosis of clinical institution «Rivne Regional Clinical Hospital» on computer tomograph General Electric Nealthcare «SignaMRI 1,5T» and in the office of magnetic resonance tomography ща clinical institution «Lutsk Clinical Hospital» on computer tomograph Signa Profile Ce Medical Sistem - 1,5 Tl in standard anatomical planes (sagittal, frontal and axial).bMeasurements were carried out in people without visual signs of organic lesions of the brain and skull. 38 tomograms of elderly patients (14 males and 24 females) were analyzed. 13 morphometric parameters of cerebrospinal fluid system of the brain were studied, namely the size of lateral, the III and IV brain ventricles and the length of aqueductus cerebri in elderly persons of both sexes. In the course of the study we determined the prevalence of size of ventricular system of the brain in males, namely the length of the anterior horns of the lateral ventricles on both sides, the length of the body of lateral ventricles on right and left parts, width of posterior horns of the lateral ventricles and the length of the lower right and left horns, anteroposterior dimensions of the lateral ventricles and the length of the III and IV ventricles. Significant interhemispheric asymmetry with increased body width and length of the rear horn of the lateral ventricle in males, increasing of the length of the lower horn of the lateral ventricle on the right side both in male and female, increasing the anteroposterior size of the left lateral ventricle in men were observed. It can be assumed that this age structural reorganization of the brain are caused by persistent metabolic changes that occur in the brain during the «aging». Conclusions. Thus, there is reason to believe that presented intravital morphometric characteristic of the human brain of elderly persons and identified on this basis criteria of age brain reorganization may be of interest to experts in the field of age anatomy, neurophysiology and neurosurgery, and for specialists of MRI-diagnostic can be an anatomical standard of ventricular system of the brain.

Changes in laboratory parameters and functional state of the left ventricle in men with overweight and obesity depending on the severity of chronic heart failure

The main links of CHF pathogenesis are: structural-geometric heart reconstruction, myocardium functional state disorder (formation of systolic and diastolic heart functions disorder), local and system inflammatory changes, specific metabolic disorders and so on. The aim of research was the study of changes of laboratory parameters and functional state of the left ventricle (LV) in men with overweight and obesity depending on CHF severity. Methods: There were examined 123 persons with CHF of I-III functional class (FC) who had normal and surplus body weight and abdominal obesity of I-III degree. All patients underwent laboratory and echocardiographic examination. The processing of received data was carried out with methods of parametric and non-parametric statistics. Results : Laboratory changes in men at CHF deepening are demonstrated in inclination to formation and spreading of anemia, kidney dysfunction and cardiogenic liver injury. With an increase of FC of disease there takes place the gradual decrease of CHF frequency with preserved emission fraction (EF) of LV at the expense of systolic dysfunction spreading. The decrease of myocardium systolic function at CHF deepening is attended with development of pulmonary hypertension parallel with spreading and deepening of diastolic dysfunction (DD) of I type. The more severe clinical course of CHF is attended with the decrease of isolated DD frequency of myocardium of I type at the expense of increase of spreading of combined systolic and diastolic dysfunction of the LV. Conclusions : With an increase of CHF FC there takes place an inclination to anemisation, formation of kidney dysfunction and cardiogenic liver injury, the spreading of systolic and diastolic LV dysfunction and pulmonary hypertension

Особливості циркумвентрикулярної системи головного мозку в осіб літнього віку

<p>Резюме. У ході морфометричного дослідження магнітно-резонансних томограм дано комплексну прижиттєву характеристику вентрикулярної системи головного мозку людини літнього віку. Вивчені гендерні особливості та міжпівкульна асиметрія відповідних показників.</p>Ключові слова: вентрикулярна система, літній вік, чоловіки, жінки, МРТ, морфометрія.

Morphometric study on dimensions of various parts of pons and comparison of data in accordance with age and sex of healthy people by MRI

Objectives: The emergence of magnetic Resonance Imaging (MRI) technique has made it possible to answer many questions in the field of anatomy more precisely while observing different anatomic parts of living persons at different ages. This study was conducted to determine the dimensions of different parts of pons and also comparing the data in accordance with age and sex by MRI.Methods: The present study carried out on 300 healthy individuals referred to imaging center at Imam Reza hospital in the city of Kermanshah, Iran. The precondition for people to be included in the study was the approval made by in-house physician based on person's state of health and the lack of any pathological lesion in brain on the basis of images obtained by MRI. Following MRI procedure, the dimensions of target parts in pons were calculated by the MRI-associated measuring system and recorded along with the age and sex of the patients. Measurements were recorded in mm and based on selecting the largest height, width and length of the organ during the examination of all axial, sagital, and T1 coronal profiles. Data analysis was performed using t-student test and Pearson's correlation. The significance level was set at P=0.05.Results: The mean size of different parts of pons recorded in mm was as follows: The height of tegmentum of pons in men and women were 21.10±1.99 and 20.35±1.95, respectively. The height of ventricle of pons was 24.96±1.45 in men and 23.72±1.41 in women. The length of pons in men was 21.40±1.55 and in women 21.10±1.28. The length of ventricle in men and women were 16.85±1.21 and 16.77±1.36, respectively. The length of tegmentum of pons was 4.57±0.50 in men and 4.40±0.58 in women. Lastly, the transverse length of the ventricle of pons was 27.30±1.68 in men and 26.52±1.63 in women.Discussion: The values obtained for the transverse length, length of tegmentum of ventricle, height of ventricle and height of tegmentum in men were larger than those found for women. There were significant relationships between the transverse length, length of tegmentum of pons, height of ventricle of pons and the age in men. There was no significant relationship between dimension of pons and age in women.

Intracerebroventricular infusion of nerve growth factor induces pain-like response in rats

New strategies have recently been developed where infusion of neurotrophic factors into the brain can rescue different neuronal populations. However, negative side effects have been observed in clinical trials infusing nerve growth factor (NGF) into the lateral ventricle in man, namely pain. Little is known about pain behavior in animals after intracerebroventricular (i.c.v.) neurotrophic injections. Thus, we have examined the effects of i.c.v. infusion of NGF for 2 weeks on the behavioral response of rats to mechanical, cold and heat stimulation. Seven micrograms/day of NGF elicited a significant decrease in vocalization threshold to mechanical stimulation and a significantly increased response to cold and heat stimuli as compared with control. The concentration of NGF in cerebrospinal fluid (CSF) was significantly increased as compared with non-allodynic rats. The enhanced responses to mechanical and heat, but not to cold, stimulation were significantly reduced by CP-99994, a selective antagonist to tachykinin NK-1 receptors. When NGF was infused into the brain parenchyma (striatum, cortex and septum) no allodynic nor hyperalgesic responses could be detected. These results indicate that in rats i.c.v. but not intraparenchymal infusion of NGF induce mechanical and cold allodynia as well as heat hyperalgesia, which is mediated, at least in part, by activation of NK-1 receptors.

Insulin-Like Growth Factor-1 (IGF-1) is Synthesized in the Transplanted Ventricle in Man with Increased Expression in Younger Recipients

Insulin-Like Growth Factor-1 (IGF-1) is Synthesized in the Transplanted Ventricle in Man with Increased Expression in Younger Recipients

Effect of a Decrease in Aortic Compliance on the Isovolumic Relaxation Period of the Left Ventricle in Man

A decrease in aortic compliance can modify the loading sequence to the left ventricular ejection in the elderly. To determine whether a decreased aortic compliance influences the left ventricular relaxation in man, 83 healthy volunteers, aged 34-87 years, were studied. The left ventricular relaxation was characterized by the isovolumic relaxation period (IRP) of the left ventricle. The aortic compliance was characterized by the aortic pulse wave velocity (AoPWV). The loading sequence to left ventricular ejection was classified into three groups by carotid pulse contour; type A, dominant tidal wave; type B, percussion wave almost equal to the tidal wave; type C, dominant percussion wave. IRP and AoPWV increased with age. The mean arterial pressure was unrelated to age. IRP was significantly related to AoPWV and mean arterial pressures. Multiple regression analysis, correlating IRP with AoPWV and mean arterial pressure, demonstrated that only AoPWV was an independent factor to explain IRP. IRP was longer in type A than in type C, and AoPWV was faster in type A than in type C volunteers. The prominent tidal wave in type A may reflect a more rapid transmission of arterial wave reflection which can result in a change of the loading sequence to the left ventricular ejection. These results reveal that a decrease in aortic compliance with aging can affect left ventricular relaxation through the change of the loading sequence in man.

Contribution of beta 1- and beta 2-adrenoceptors of human atrium and ventricle to the effects of noradrenaline and adrenaline as assessed with (-)-atenolol.

1. (-)-Atenolol was used as a tool to assess the function of beta 1- and beta 2-adrenoceptors in human heart. Right atrial and left ventricular preparations from patients undergoing open heart surgery were set up to contract isometrically. Membrane particles were prepared for beta-adrenoceptor labelling with [3H]-(-)-bupranolol and adenylate cyclase assays. 2. The positive inotropic effects of (-)-noradrenaline were antagonized to a similar extent by (-)-atenolol in atrial and ventricular preparations. (-)-Atenolol consistently antagonized the effects of (-)-adrenaline to a lesser extent than those of (-)-noradrenaline in atrial preparations. In ventricular preparations (-)-atenolol antagonized the effects of low concentrations of (-)-adrenaline to a lesser extent than those of high concentrations. 3. pKB values (M) of (-)-atenolol, estimated with non-linear analysis from the blockade of the positive inotropic effects of the catecholamines, were 7.4 for beta 1-adrenoceptors and 6.0 for beta 2-adrenoceptors. 4. (-)-Atenolol inhibited the binding of [3H]-(-)-bupranolol to ventricular beta 1-adrenoceptors with a pKD (M) of 5.9 and to ventricular beta 2-adrenoceptors with a pKD of 4.6. 5. (-)-Atenolol inhibited the catecholamine-induced adenylate cyclase stimulation in the atrium and ventricle with pKB values of 5.8-6.4 for beta 1- and pKB values of 4.7-5.7 for beta 2-adrenoceptors. The binding and cyclase assays suggest a partial affinity loss for (-)-atenolol inherent to membrane preparations. 6. beta 1-Adrenoceptors mediate the maximum positive inotropic effects of (-)-noradrenaline in both the atrium and ventricle of man. beta 2-Adrenoceptors appear to be capable of mediating maximal positive inotropic effects of (-)-adrenaline in atrium. In contrast, ventricular beta 2-adrenoceptors mediated only submaximal effects of (-)-adrenaline.

Ependymal foldings and other related ependymal structures in the cerebral aqueduct and fourth ventricle of man.

The ependymal lining of the cerebral aqueduct and fourth ventricle of 100 normal humans was studied with the light microscope. Ependymal foldings with normal morphology and a constant distribution pattern were detected in all. The most common sites were the median sulcus and sulcus limitans in the fourth ventricle, and the ventral and lateral walls in the cerebral aqueduct. Rows, islands and rosettes of ependymal cells embedded in normal subependyma were present in 25/82 adults (30%) and in 3/18 children (16%) in a similar distribution pattern as that of the ependymal foldings. We illustrate these normal structures which probably result from fusion between the walls of the ependymal foldings and distinguish them from granular ependymitis and postmortem artifact.

Cineangiographic evaluation of diastolic properties of the left ventricle in man.

Diastolic properties of the left ventricle were evaluated cineangiographically in 110 patients with various heart diseases (19 normal cases, 13 mitral stenosis, 19 left ventricular volume overload, 18 coronary artery diseases without myocardial infarction, 27 myocardial infarction, 6 hypertrophic cardiomyopathy, 5 congestive cardiomyopathy and 3 chronic constrictive pericarditis). Early diastolic ventricular filling was assessed by diastolic maximal circumferential relaxation velocity (maxVcf), diastolic maximal dV/dt, volume change during early 1/3 of ventricular filling (V1/3), rapid filling time and isovolumic relaxation time; myocardial stiffness constant K was calculated at end-diastole. Increase in myocardial stiffness constant was not necessarily associated with abnormal indices measured during the early diastolic period but well correlate with isovolumic relaxation time. During the isovolumic relaxation period, the affected left ventricular segments where myocardial infarction or myocardial hypertrophy existed, showed reduced and delayed relaxation resulting in a total increase in the isovolumic relaxation period. Calcium antagonist was effective in improving the delayed relaxation in patients with left ventricular hypertrophy, suggesting a role of calcium on delayed myocardial relaxation in the hypertrophied heart.

Effect of diuresis on the performance of the failing left ventricle in man : Wilson JR, Reichek N, Dunkman WB, Goldberg S: Am J Med 1981; 70: 234–239

Effect of diuresis on the performance of the failing left ventricle in man : Wilson JR, Reichek N, Dunkman WB, Goldberg S: Am J Med 1981; 70: 234–239

Effect of diuresis on the performance of the failing left ventricle in man

To determine the effect of diuresis on the performance of the failing left ventricle, we measured cardiac output, pulmonary wedge pressure and M-mode echo left ventricular diastolic dimension before and after diuresis in 13 patients with heart failure. Diuresis increased stroke volume (43 ± 23 ml to 50 ± 18 ml (p < 0.05) and decreased pulmonary wedge pressure (28 ± 3 mm Hg to 19 ± 5 mm Hg (p < 0.01)), mean blood pressure (100 ± 14 mm Hg to 88 ± 10 mm Hg (p < 0.01)) and systemic vascular resistance (2,059 ± 622 dynes-sec-cm−5 to 1,783 ± 556 dynes-sec-cm−5 (p < 0.05)). Echo left ventricular diastolic dimension was not changed by diuresis (6.0 ± 0.8 cm to 6.0 ± 0.8 cm). Percent change in stroke volume correlated with systemic vascular resistance (r = 0.60, p < 0.05) and with left ventricular diastolic dimension (r = 0.62, p < 0.05) but not with pulmonary wedge pressure (r = 0.12) or right atrial pressure (r = 0.04). Thus, diuresis improved the performance of the failing ventricle and reduced afterload, but it did not alter left ventricular diastolic dimension, an index of preload. These data suggest that diuresis improves ventricular function by decreasing afterload.

Electro- and echocardiographic study of the left ventricle in man after training.

Fourteen sedentary middle-aged men underwent a chest X-ray, a 12 lead ECG, a VCG, and an echocardiographic examination prior to and following 5 months of training a moderately severe intensity, on a cycle ergometer. No modification in the X-ray cardiac profile was observed following training. Some electrocardiographic (R wave amplitude in V5 and V6 and Sokolow index: SV1 + RV5 or V6) and vectorcardiographic (maximal QRS vector amplitude, maximal spatial QRS vector, and R wave amplitude) indices of left ventricular hypertrophy were slightly but significantly increased following training. The echocardiographic measurements in diastole (septal and posterior wall thickness, left ventricular internal diameter, and left ventricular mass) were unchanged after training. Results suggest that electrical changes may not provide adequate indications of left ventricular morphological modifications. The lack of echocardiographic evidences of left ventricular hypertrophy suggest that: (1) training does not necessarily induce left ventricular hypertrophy; (2) the large heart sometimes observed in athletes may be the result of a genetic factor or of a prolonged and very intensive training pursued since a very young age, over a number of years; and (3) left ventricular enlargement probably plays a minor role in the increase in aerobic capacity following training.

A simple technique for producing cast specimens of the cardiac ventricles.

In a convenient method, a methacrylate dental plastic, Kallocryl C, was used to make cast specimens of both ventricles of man. The casts are suitable for use in comparative measurements and highly accurate determinations of ventricular volumes.

Effect of mexiletine on monophasic action potentials recorded from the right ventricle in man.

The effect of mexiletine, a new antiarrhythmic agent, on ventricular refractoriness and monophasic action potentials recorded from the right ventricle was studied in nine subjects. The effective refractory period of the right ventricle was determined by the extra stimulus technique using a pacing electrode situated at the right ventricular apex. Following this determination the right ventricular apex was paced at a constant cycle length and premature stimuli were introduced starting at a coupling interval of 2 ms greater than the ventricular refractory period and then at progressively increasing coupling intervals of 5 ms increments. Simultaneous recordings of monophasic action potentials of both the regular paced beats and the induced premature beats were made using a specially designed suction electrode catheter. The monophasic action potential durations were measured at 50% and 90% repolarisation. All these control measurements were repeated after an intravenous dose of 2 mg.kg-1 body wt. of mexiletine. The results showed that mexiletine did not significantly change the effective ventricular refractory period nor did it alter the monophasic action potential duration of the regular paced beat. The drug did, however, significantly prolong the monophasic action potential duration of the early induced premature beats and it is possible that this property of the drug may be related to its antiarrhythmic activity.

Diastolic simple elastic and viscoelastic properties of the left ventricle in man.

The intrapatient comparison of the simple elastic and viscoelastic stress-strain relationship showed a significantly better curve fitting (r = 0.93 vs 0.96) for the viscoelastic model. The correction by the viscoelastic model occurred mainly during the highly filling-rate dependent early diastole, whereas the correction during atrial filling was low. Early diastolic deviations from the simple elastic stress-strain relationship were especially pronounced in the patients with myocardial hypertrophy. The viscoelastic constants of myocardial stiffness, B and K, were significantly different from the corresponding simple elastic constants, b and k, indicating that the simple elastic stiffness constants include both elastic and viscous forces.

Contractile state of the left ventricle in man as evaluated from end-systolic pressure-volume relations.

End-systolic pressure (PES), volume (VES), wall tension (TES) and circumference (CES) of the human left ventricle were studied at cardiac catheterization in 24 subjects with varying degrees of left ventricular dysfunction. Acute alterations in systolic load consistently resulted in changes in VES and CES, with a smaller volume and circumference characterizing the lower systolic load in each subject. End systolic pressure-volume lines were constructed by plotting PES against VES at the higher and lower systolic load in each subject. The slope of the resultant lines was considerably steeper for normal than for poorly contractile left ventricles. Vo, the volume axis intercept of the line (i.e., the theoretical VES at PES = O) was significantly smaller for normal than for poorly contractile ventricles. Similar findings were noted for Co, the theoretic end-systolic circumference at zero end-systolic ventricular wall tension. Post-extrasystolic potentiation resulted in decreased VES and CES with no change in PES and only a slight fall in TES. In conclusion, end-systolic pressure-volume and tension-circumference relations reflect the contractile state of left ventricular myocardium. Quantitation of these relationships may provide a useful new approach to the assessment of myocardial function in man.

Calcium containing particles in mitochondria of heart muscle cells as shown by cryo-ultramicrotomy and X-ray microanalysis

Mitochondria of normal myocardial cells of the sand rat and the mouse as well as of the left ventricle of man, have been examined for their content of calcium. Ultrahistochemistry and X-ray microanalysis revealed two basically different inclusions: Osmiophilic mitochondrial granules and spherical mitochondrial particles. Osmiophilic mitochondrial granules were found in conventionally fixed and plastic embedded tissues as well as in cryosections of chemically fixed and sucrose infused tissues. Such granules lacked inert electron density and probably consisted mainly of unsaturated lipids. X-ray spectra obtained from these tissues revealed no peaks for calcium. Spherical mitochondrial particles were present in dry-cut cryo-sections of N2-frozen tissues not treated by fixatives and/or cryoprotectants. These particles were deeply electron dense in unstained, freeze-dried cryo-sections. They usually measured from 600 A-900 A in diameter in the normal myocardium of the sand rat and the mouse and from 250 A-400 A in diameter in the left ventricular myocardium of man. Significant calcium peaks could be identified in the X-ray spectra of these particles, whereas none occurred in the analyses of other tissue regions. Potassium was detected with about equal frequency in the particles and in other parts of the tissue. On the basis of the inert electron density of the particles and their absence in chemically fixed tissues as well as of the results of the X-ray analysis, it is concluded that they contain precipitates of extremely labile ions of mitochondrial calcium.