Ferritin-mediated iron detoxification promotes hypothermia survival in Caenorhabditis elegans and murine neurons

How animals rewire cellular programs to survive cold is a fascinating problem with potential biomedical implications, ranging from emergency medicine to space travel. Studying a hibernation-like response in the free-living nematode Caenorhabditis elegans, we uncovered a regulatory axis that enhances the natural resistance of nematodes to severe cold. This axis involves conserved transcription factors, DAF-16/FoxO and PQM-1, which jointly promote cold survival by upregulating FTN-1, a protein related to mammalian ferritin heavy chain (FTH1). Moreover, we show that inducing expression of FTH1 also promotes cold survival of mammalian neurons, a cell type particularly sensitive to deterioration in hypothermia. Our findings in both animals and cells suggest that FTN-1/FTH1 facilitates cold survival by detoxifying ROS-generating iron species. We finally show that mimicking the effects of FTN-1/FTH1 with drugs protects neurons from cold-induced degeneration, opening a potential avenue to improved treatments of hypothermia.

Strategies to improve cold resistance are of potential biomedical interest. Here the authors demonstrate that ferritin-mediated detoxification of iron, preventing the generation of reactive oxygen species, promotes cold survival in both Caenorhabditis elegans and cultured mammalian neurons.

Left ventricular systolic function parameters are increased in patients with primary biliary cholangitis without cirrhosis

Funding Acknowledgements

Type of funding sources: None.

Background

Primary biliary cholangitis (PBC) is a chronic, autoimmune liver disease causing destruction of the small intralobular bile ducts in the liver. PBC patients can also develop extrahepatic manifestations, mostly related to skin, nervous system and laboratory abnormalities. Cardiac involvement is inconsistent in PBC studies despite high levels of serum lipids. Cardiac abnormalities are especially important because with the treatment many patients with early-stage PBC may have a normal life expectancy and therefore the cardiovascular complications can develop. Additionally, in recent years new echocardiographic modalities emerged letting for more precise analysis of cardiac morphology and function.

Purpose

The purpose of the study was to compare novel and classic echocardiographic indices in patients with confirmed PBC without cirrhosis and in control subjects.

Methods

22 female patients with PBC and without cirrhosis and 44 healthy females, matched for age, (53.3 ± 9 years and 50.9 ± 8 years respectively, p = 0.065) were investigated. TTE study was performed and analysis of left ventricular (LV) global longitudinal strain (GLS) and myocardial work was performed.

Results

Systolic blood pressure (SBP) differed between PBC and control group  (128 ± 17 mmHg and 116 ± 11 mmHg respectively, p = 0.006),  while diastolic blood pressure (DBP) (78 ± 10 mmHg and 76 ± 10 mmHg, p = 0.2) and heart rate (HR) (73 ± 12 bpm and 70 ± 8 bpm , p = 0.32) did not. PBC group had increased diameter of cardiac chambers when adjusted for body surface area (BSA), including left atrium (LA/BSA) and right ventricle (RV/BSA), as well as left ventricular mass (LWMI) and relative wall thickness (RWT) (Table) with no difference in left ventricular end diastolic diameter (LVEDD/BSA). LV ejection fraction (EF) measured by Simpson method was increased in PBC group (Table).  LV diastolic function parameters (E/A, E/e’) were impaired in patients with PBC when compared with controls (Table 1). LV GLS indices (GLSAVG, GLSLAX, GLS4C, GLS2C) were significantly higher in PBC group, as well as global myocardial work indexes : global myocardial work (GWI) and global constructive work (GCW).  Global work efficiency (GWE) and global wasted work (GWW)  indexes were not different (Table).

Conclusion

Our study shows that in patients with PBC without cirrhosis LV systolic function is increased. That implies hyperkinetic circulation in that group of patients even before the development of  cirrhosis. Abstract Table

Weight reduction after bariatric surgery improves myocardial work indices and global longitudinal strain

Funding Acknowledgements

Type of funding sources: None.

Background

Obesity is known to affect cardiovascular morphology, function and outcomes. Most parameters used to evaluate cardiac function, especially ejection fraction, but also strain are load dependent and the research focused on the effects of the weight loss on cardiac systolic function are inconsistent.  Myocardial work is a novel cardiovascular parameter that characterizes cardiac systolic function and is less load dependent. However, there is lack of data how bariatric surgery affects parameters of the non-invasively calculated myocardial work indices obtained from pressure-strain loops obtained in patients referred with severe obesity.

Purpose

The purpose of the study was to analyze whether myocardial work indices change after bariatric surgery.

Methods

Out of 171 consecutive subjects that were referred to bariatric surgery and characterized elsewhere (1) 15 subjects, that had both, adequate visualization, and post- surgery transthoracic echo (TTE) performed, were taken into analysis. Echocardiographic examination was performed using GE Vivid 9 and analyzed with EchoPac 204 software.

Results

Global myocardial work (GWI), global constructive work (GCW) and global work efficiency (GWE) indexes increased, while global wasted work index (GWW) decreased significantly after bariatric surgery (Figure). GLS increased significantly after bariatric surgery (Figure). LV ejection fraction did not change significantly after surgery (60.2 ± 6.5% vs. 60.9 ± 7 %, p = 0.68). LV end-diastolic diameter (LVEDD) did not change (4.86 cm ± 0.35 vs. 4.89 cm ± 0.38, p = 0.55), while posterior wall thickness (PW) and relative wall thickness (RWT) decreased significantly (1.08 ± 0.13 vs. 0.99 ± 0.13, p = 0.001 and 0.45 ± 0.05 vs. 0.41 ± 0.06, p= 0.0003, respectively). Left atrial diameter (Figure) and left atrial area were lower after bariatric surgery (18.6 cm2 ± 2.5 vs. 16.7 cm2 ± 2.5, p = 0.027). Both systolic blood pressure and heart rate decreased after bariatric surgery (Figure). Mean time to post – surgery TTE was 400 days ± 151 and mean weight reduction was 38 kg ± 8.

Conclusion

Left ventricular systolic function evaluated using myocardial work indexes increased after bariatric surgery. After bariatric surgery, the myocardial work parameters returned to normal range, when based on the values recorded in the reference STAAB cohort study (2). Abstract Figure

Individualizing the target diastolic blood pressure in patients being treated for hypertension and diabetes

Background/Introduction

The J-curve hypothesis in hypertension is related to an increased risk of cardiovascular events associated with both too high and too low diastolic blood pressure (DBP) values.

European Society of Cardiology recommended DBP in the range of 70–80 mm Hg as a treatment target for subjects with hypertension, regardless of age, history of cardiovascular disease (CVD) or diabetes mellitus (DM) presence.

Such a recommendation is based on studies performed in subjects with prior CVD. There is no scientific evidence to support a target DBP of 70–80 mmHg in people with DM and without history of CVD.

Purpose

The aim of the study is to determine the relationship between DBP and cardiovascular risk according to age and the presence of CVD in people with DM.

Methods

The ACCORD study dataset (participants with diabetes) available from National Heart, Lung and Blood Institute was used to perform the analysis.

The DBP value during the study was defined as the mean of all DBP measurements obtained during the study individually for each participant.

The composite endpoint (CE) was defined as myocardial infarction, stroke, exacerbation of heart failure or cardiovascular death.

The relationship between the DBP value during the study and the risk of CE was presented using the Cox proportional hazard model and spline curves.

This analysis was performed for 4 sub-populations defined on the basis of 2 criteria: age <65 years and the presence of CVD in the past. Each model was adjusted for other cardiovascular risk factors (age, sex, smoking, systolic blood pressure, chronic kidney disease).

Results

The data of 4,733 participants of the ACCORD BP study were analyzed. The table (Figure 1) presents the baseline characteristics of the 4 sub-populations and CE occurrence.

For each sub-population studied, a Cox model describing the relationship between DBP during the study and CE risk was developed and presented in the Figure 2.

In subjects with CVD the J-curve relationship between DBP and CE risk was observed. Among subjects without prior CVD, no J-curve relationship was observed.

Conclusions

Optimal DBP treatment target in subjects with CVD and DM is slightly lower than the currently recommended range of 70–80 mm Hg.

DBP values in the range of 70–80 mm Hg should not be recommended as the treatment target for subjects with DM and no history of CVD.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

The impact of resting heart rate measured on cardiovascular events in subject with hypertension

Background

Available evidence does not indicate whether resting heart rate (RHR) is an independent risk factor or just marker of elevated risk. None of the studies assessed impact of RHR on cardiovascular events, when RHR was measured using automated blood pressure measurements (AOBPM).

Purpose

To assess the relationship between RHR (measured using AOBPM) and cardiovascular events risk in subjects with hypertension.

Methods

The data of SPRINT trial obtained via NHLBI were used to perform the analysis. SPRINT trial assessed intensive lowering of systolic BP to a target <120 mm Hg in comparison to standard goal (<140 mm Hg).

RHR was measured using AOBPM device and calculated as an average of 3 measurements during the baseline visit of the study.

Clinical composite endpoint (CE) of the study was defined as: myocardial infarction, acute coronary syndrome, decompensation of heart failure, stroke or cardiovascular death.

The relationship between RHR and CE was assessed according to presence of cardiovascular disease (CVD) in past medical history.

The statistical methods included t-test and chi-square test, Cox proportional risk models. The Cox models were adjusted for adjusted for age, sex, current smoking status and mean SBP during the trial. Restricted cubic splines were used to describe the relationship between RHR and hazard ratio.

Results

Data of 1877 participants with CVD and 7484 participants without CVD were analyzed. Subjects with cardiovascular disease were older (69.7±9.5 vs 67.5 years ± 9.4, p<0.001), more often were men (72.8% vs 62.3%, p<0.001) and had prior chronic kidney disease (34.3% vs 26.8%, p<0.001) than subjects without CVD. CE was more than twice often when CVD was present (10.9% vs 4.8%, p<0.001). RHR was lower in subjects with CVD disease than in subjects without CVD (63.6±11 vs 66.9±11.6 bpm, p=0<00.1). Elevated RHR was associated with increased risk both in subjects with and without CVD (Figure 1).

The multivariable Cox proportional hazard risk model revealed that RHR>80 bpm is an independent risk factor for CE in subjects without CVD (hazard ratio 1.37, 95% CI 1.01–1.85, p=0.043) while not in subjects with CVD (hazard ratio 0.99, 95% CI 0.57–1.71, p=0.98).

Conclusion

Elevated RHR (>80 bpm) measured using AOBPM is an independent risk factor for cardiovascular events in subjects with hypertension and without CVD.

Figure 1. Heart ratio vs hazard ratio.

Funding Acknowledgement

Type of funding source: None

P798Automated blood pressure measurements: optimal diastolic blood pressure range in treated hypertensives at high cardiovascular risk

Background/Introduction

Automated office blood pressure measurements (AOBPM) is recommended for the diagnosis of arterial hypertension. Nevertheless, use of automated office blood pressure in monitoring of treated patients with hypertension is limited by the discrepancies between AOBPM, auscultatory and research grade measurements of blood pressure. The treatment targets using AOBPM are not well-determined.

Purpose

This post-hoc analysis is aimed to establish the optimal range for on-treatment diastolic blood pressure (DBP) measured with AOBPM in hypertensive patients without cardiovascular disease but at high risk, who achieved systolic blood pressure treatment goal (SBP).

Methods

Data of 3715 subjects without prior cardiovascular disease treated to achieve SBP goal <120 mm Hg were selected from SPRINT trial database obtained from National Heart, Lung and Blood Institute. Clinical endpoint was defined as myocardial infarction, acute coronary syndrome not resulting in myocardial infarction, stroke, acute decompensated heart failure or death from cardiovascular causes.

On-treatment blood pressure was computed as mean of AOBPM readings in a period from 6th month until to end of the study, which was considered as with a stable blood pressure.

Optimal on-treatment DBP range was established on the basis of hazard ratio plot for clinical endpoint after adjustment for age, sex, SBP, smoking habits and history of chronic kidney disease. The target DBP range was set to be 10 mm Hg wide, what is line with current ESC/ESH guidelines. To evaluate nonlinear relationship between continuous variables and outcome cubic spline methods were used.

Results

Data of 3715 (38.3% female and 61.7% male) subjects aged 67.3±9.2 mm Hg were analysed. Mean on-treatment SBP and DBP were 120.8±8.5 mm Hg and 68.2±8.1 mm Hg, respectively. Lowest hazard risk of primary endpoint was found in on-treatment DBP range 62.8–72.8 mm Hg with a minimum at 67.8 mm Hg (Figure 1). Hazard risk increased linearly toward lower and higher values than selected optimal DBP range.

Figure 1

Conclusion(s)

In treated hypertensives at high cardiovascular risk, but without prior cardiovascular disease who achieved SBP treatment goal, on treatment DBP 62.8–72.8 mm Hg range should be considered when treatment is monitored using AOBPM.

The impact of in vitro cell culture duration on the maturation of human cardiomyocytes derived from induced pluripotent stem cells of myogenic origin

Ischemic heart disease, also known as coronary artery disease (CAD), poses a challenge for regenerative medicine. iPSC technology might lead to a breakthrough due to the possibility of directed cell differentiation delivering a new powerful source of human autologous cardiomyocytes. One of the factors supporting proper cell maturation is in vitro culture duration. In this study, primary human skeletal muscle myoblasts were selected as a myogenic cell type reservoir for genetic iPSC reprogramming. Skeletal muscle myoblasts have similar ontogeny embryogenetic pathways (myoblasts vs. cardiomyocytes), and thus, a greater chance of myocardial development might be expected, with maintenance of acquired myogenic cardiac cell characteristics, from the differentiation process when iPSCs of myoblastoid origin are obtained. Analyses of cell morphological and structural changes, gene expression (cardiac markers), and functional tests (intracellular calcium transients) performed at two in vitro culture time points spanning the early stages of cardiac development (day 20 versus 40 of cell in vitro culture) confirmed the ability of the obtained myogenic cells to acquire adult features of differentiated cardiomyocytes. Prolonged 40-day iPSC-derived cardiomyocytes (iPSC-CMs) revealed progressive cellular hypertrophy; a better-developed contractile apparatus; expression of marker genes similar to human myocardial ventricular cells, including a statistically significant CX43 increase, an MHC isoform switch, and a troponin I isoform transition; more efficient intercellular calcium handling; and a stronger response to β-adrenergic stimulation.

Does field hockey increase morphofunctional asymmetry? A pilot study

Common practice in field hockey requires athletes to adopt a semi-crouched posture, so players have a greater risk of musculoskeletal disorders than non-athletes. The aim of the present study was to assess how field hockey determines asymmetry in morphological and functional characteristics of the body by comparing athletes to control participants. The sample consisted of 15 male field hockey players from the Polish Youth National Team and 14 male university students. Antimeric differences in the chosen variables between body sub-regions were assessed. All morphological characteristics (bone mineral density, fat mass, and lean mass) were estimated using a dual energy X-ray absorptiometry. Additionally, the range of motion in transverse and frontal planes of the cervical, thoracic and lumbar spine was measured by using an electrogoniometric system. The results showed that the values of all morphological characteristics were higher in the left body segments, both in athletes and controls. However, the differences between sides were much more pronounced in the field hockey players. With regard to functional traits, higher values were obtained for the right body side in athletes but for the left side of the body among the controls. The difference between right and left side bending increased from the cervical spine (2.7%) through thoracic spine (7.8%) to lumbar spine (16.5%) in athletes. Rotational asymmetry in the thoracic spine was the largest in both groups. These findings indicate that it is important to monitor all athletes to prevent injury and health problems connected with strong morphological asymmetry.

Techniques for the induction of human pluripotent stem cell differentiation towards cardiomyocytes

The derivation of pluripotent stem cells from human embryos and the generation of induced pluripotent stem cells (iPSCs) from somatic cells opened a new chapter in studies on the regeneration of the post-infarction heart and regenerative medicine as a whole. Thus, protocols for obtaining iPSCs were enthusiastically adopted and widely used for further experiments on cardiac differentiation. iPSC-mediated cardiomyocytes (iPSC-CMs) under in vitro culture conditions are generated by simulating natural cardiomyogenesis and involve the wingless-type mouse mammary tumour virus integration site family (WNT), transforming growth factor beta (TGF-β) and fibroblast growth factor (FGF) signalling pathways. New strategies have been proposed to take advantage of small chemical molecules, organic compounds and even electric or mechanical stimulation. There are three main approaches to support cardiac commitment in vitro: embryoid bodis (EBs), monolayer in vitro cultures and inductive co-cultures with visceral endoderm-like (END2) cells. In EB technique initial uniform size of pluripotent stem cell (PSC) colonies has a pivotal significance. Hence, some methods were designed to support cells aggregation. Another well-suited procedure is based on culturing cells in monolayer conditions in order to improve accessibility of growth factors and nutrients. Other distinct tactics are using visceral endoderm-like cells to culture them with PSCs due to secretion of procardiac cytokines. Finally, the appropriate purification of the obtained cardiomyocytes is required prior to their administration to a patient under the prospective cellular therapy strategy. This goal can be achieved using non-genetic methods, such as the application of surface markers and fluorescent dyes. Copyright © 2016 John Wiley & Sons, Ltd.

Laparoscopic adrenalectomy - ten-year experience

Objectives

The objective of the study is to summarize the authors’ 10-year experience with laparoscopic adrenalectomy and to analyze the intra- and postoperative complications of the procedure.

Material and methods

The records of 80 patients who had undergone laparoscopic adrenalectomy from January 2002 to January 2012 were reviewed retrospectively. There were 51 female and 29 male patients. The average age was 52. In 33 cases the right adrenal gland was affected, in 47 it was the left adrenal gland. Nineteen operations were performed with the retroperitoneal approach, in 61 a transperitoneal access was used. The average size of the tumor was 5 cm. The diagnosis was based on ultrasonography (USG) and computed tomography (CT). The biochemical tests were performed in all cases to assess hormonal activity of the tumor. Pheochromocytoma was diagnosed in 16 cases, Cushing syndrome in 3 cases, and Conn syndrome in 4 cases. All other tumors were hormonally inactive. Six patients were operated on because of adrenal metastases – from renal carcinoma in five cases and from lung carcinoma in one case.

Results

There were three open conversions. The mean operative time was 158 minutes. The mean hospital stay was 5.5 days Blood transfusion was necessary in three patients. Postoperative complications were observed in 11 patients (13.7%).

Conclusions

Laparoscopic adrenalectomy is a safe and effective procedure and should be considered the first – line treatment of benign adrenal masses. Our experience indicates that patients with adrenal metastases are suitable candidates for laparoscopic adrenalectomy, providing a skilled laparoscopic surgeon is involved in operation.

Nasal septum morphology in human fetuses in computed tomography images

Objectives

Nasal septum deformation (NSD) may cause breathing dysfunction. The reason for a septal deviation is the developmental anomaly in growth of the elastic septum or its skeleton. Such a type of deviation is called physiological. Some deviations can result from the prenatal trauma. The aim of the work was the analysis of the anatomy of the nasal cavity with a special interest focused on the nasal septum and its deviation.

Materials and methods

The nasal cavity with its bones and septum was analyzed in CT images of 105 spontaneously aborted fetuses (57 males and 48 females) aged 12 and 40 weeks of gestation. We attempted to assess the morphometric development of the nasal cavity with tomographic scanning methods and to detect anatomical variations.

Results

In 15 (14.3%) fetuses, NSD were detected on radiological sections. The angle between the virtual line from the sphenoid sinus ostium through limen nasi and the horizontal plane was 33.6 ± 2.3°, on average.

Conclusions

NSD may already be found in fetuses. The observation of the nasal cavity development enables to evaluate the growth and symmetry of the nasal septum and to foretell predispositions for dysfunction in the upper respiratory tract.

Why study sympathetic nervous system?

Cardiovascular diseases are the most frequent causes of morbidity and mortality around the world. However, during last decades, an improvement was made in diagnosis and therapy of cardiovascular diseases, there was still a need for better understanding of their pathophysiology. Among neurohormonal systems, SNS plays a central role in cardiovascular regulation in both health and disease. Involvement of SNS in pathogenesis of hypertension, coronary artery disease or heart failure is well known and proved. Methods such as microneurography, direct catecholamine measurements, heart rate variability or baroreflex sensitivity assessment allowed studying sympathetic activity and its influence on cardiovascular disorders. Although introduced into scientific practice methods of SNS evaluation are not commonly used in the clinic. However, two of the methods: analysis of heart rate variability (HRV) and baroreflex sensitivity (BRS) were recommended as the diagnostic tools and can be found in clinical guidelines as basic assessment methods.

Glycocalyx-mimetic dextran-modified poly(vinyl amine) surfactant coating reduces platelet adhesion on medical-grade polycarbonate surface

A dextran-modified poly(vinyl amine) comb-like surfactant polymer, poly(N-vinyl dextran aldonamide-co-N-vinyl hexanamide), that can surface-adsorb on hydrophobic polymeric substrates, was designed to improve the interfacial blood-compatibility of polymeric biomaterials. Medical-grade polycarbonate was selected as a model substrate because of its extensive use in blood-contacting biomedical devices like hemodialyzers, blood pumps and oxygenators. The surfactant polymer was physisorbed from aqueous solution onto the polycarbonate substrate. The surfactant coating was stable under dynamic shear conditions in whole blood, as confirmed by fluorescence microscopy and total internal reflection fluorescence (TIRF) experiments with fluorescein-labeled surfactant polymer. The coated disks and uncoated control disks were exposed to platelet-rich plasma (PRP) and whole human blood in a rotating disk system (RDS) to study platelet-adhesion under dynamic shear stress environments. Adhered platelets were stained with fluorescein isothiocyante (FITC)-tagged anti-CD41a monoclonal antibody and imaged by epifluorescence microscopy. Complimentary images were obtained by phase-contrast microscopy. Platelet adhesion on the surfactant-coated disks was reduced by approximately 90%, compared with uncoated disks. The images also showed a concomitant reduction in platelet-derived microparticles on surfactant-coated disks, compared with uncoated disks. The results suggest potential application of carbohydrate-modified surfactant polymers as a glycocalyx-mimetic non-thrombogenic interfacial coating for blood-contacting biomaterials.

Verification of selected anatomic landmarks used as reference points for universal goniometer positioning during knee joint mobility range measurements

The study was concerned with verification of the selection of reference points used for knee joint mobility range goniometry. The verification was based on photometric and electrogoniometric methods of femorotibial angle measurements. The material for measurements were three knee joint preparations. The obtained data were subjected to descriptive analysis; photographic documentation of geometric relations between the reference points was also prepared. Considerable divergence of measurement results was observed with respect to the actual knee joint flexion angle, amounting even to 16 degrees. The differences are due to the selection of anatomic landmarks, and depend in particular on the distance of the point to which the goniometer axis is applied from the approximate location of the mechanical joint axis. The corrections of knee joint flexion angle measurements were also estimated on the basis of data obtained from the photographs and the derived mathematical formula.

Generic isolated horizons and their applications

The notion of isolated horizons is extended to allow for distortion and rotation. Space-times containing a black hole, itself in equilibrium but possibly surrounded by radiation, satisfy these conditions. The framework has three types of applications: (i) it provides new tools to extract physics from strong field geometry; (ii) it leads to a generalization of the zeroth and first laws of black hole mechanics and sheds new light on the "origin" of the first law; and (iii) it serves as a point of departure for black hole entropy calculations in nonperturbative quantum gravity.

Blood pressure, plasma NPY and catecholamines during physical exercise in relation to menstrual cycle, ovariectomy, and estrogen replacement

Some evidences indicate that the female sex hormones protect against the development of cardiovascular diseases. Modulation of sympathetic activity may be one of the possibilities. We investigated the influence of treadmill stress on blood pressure (BP) and plasma neuropeptide Y (NPY), norepinephrine (NE) and epinephrine (E) concentrations in 11 normotensive, menstruating women in the follicular (HWf) and luteal (HWl) phases and in eight ovariectomized women, before (OVX) and after estrogen supplementation (OVXe). Both at rest and during exercise there were no differences in BP between HWf and HWl and between OVX and OVXe. During stress BP was significantly lower in HWf and HWl than in OVX but not in OVXe. NPY did not differ significantly between the groups of women either at rest or during activity. We did not observe differences in resting and stimulated NE and E between HWf and HWl and between OVX and OVXe. Neither resting nor activated NE and E differed between the groups, except higher stimulated NE in OVX than in HWf. These results suggest that the female sex hormones may modulate the BP response to dynamic exercise. Our data support evidence that this influence may be exerted by circulating catecholamines and not by NPY.

Hemorrheological indices, catecholamines, neuropeptide Y and serotonin in patients with essential hypertension

Hemorrheological and humoral abnormalities and excessive platelet activity can predict the development of cardiovascular complications in patients with essential hypertension. A study was conducted to assess the influence of gender on these factors and the interrelations between changes in hemorrheology and the sympatho-adrenal system in 54 patients (18 women, 36 men) with essential hypertension (aged 39.6 +/- 9.7 years) and 25 healthy volunteers (10 women, 15 men; aged 36.0 +/- 7.2 years). A decrease in erythrocyte deformability (p < 0.01) was found in the hypertensive men compared with the hypertensive women. Hematocrit (p < 0.01), blood viscosity at the shear rates of 0.3 s-1 (p < 0.01) and 6 s-1 (p < 0.01), plasma viscosity (p < 0.01), erythrocyte aggregation (p < 0.01), and neuropeptide Y (p < 0.02) concentrations were higher in the hypertensive men than in the hypertensive women. A positive correlation between blood fibrinogen and serotonin was found in the pooled hypertensive group and in the hypertensive men (p < 0.01) and between blood viscosity (shear rate 6 s-1) and neuropeptide Y in the pooled hypertensive group (p < 0.01). Neuropeptide Y correlated with filtration time of 1 mL blood in the hypertensive men (p < 0.05) and in the pooled normotensive group (p < 0.01) and with beta-thromboglobulin in the hypertensive women (p < 0.001). A positive correlation was also found in the hypertensive men between erythrocyte and platelet aggregation (p < 0.01) and between beta-thromboglobulin and adrenaline (p < 0.01). Hemorrheological and humoral abnormalities are more pronounced in men than in women with essential hypertension and may contribute to the increased incidence of cardiovascular events in men.

Evaluation of plasma aldosterone to plasma renin activity ratio in patients with primary aldosteronism

The plasma aldosterone to renin activity ratio (A/PRA) was assessed retrospectively in 103 patients with primary aldosteronism including 74 patients with surgically proven adrenal cortical adenoma (APA) and 29 patients with idiopathic adrenal cortical hyperplasia (IHA). The results were compared with those obtained in 31 patients with essential hypertension (EH) and 45 healthy normotensive controls. The upper limit of normal A/PRA ratio, as obtained in the controls was 17.8. This value was exceeded in 89% of patients with APA; postoperatively it decreased in 97% of the APA group, and returned to normal in 81%. In the IHA group the A/PRA was elevated in 70% of patients. The normal ratios in patients with primary aldosteronism were associated with unsuppressed plasma renin activity (PRA). Although the mean values of the A/PRA ratio differed significantly between the groups, complete separation was not obtained. The serum potassium level at time of testing did not influence the diagnostic value of the A/PRA ratio, although an inverse correlation between serum potassium and the A/PRA ratio was found in the patients with APA. This study supports the high sensitivity of the A/PRA ratio in diagnosis of primary aldosteronism, however, a single determination with a normal result may not be sufficient for exclusion of the disease.

Formation of morphological traits of the quadriceps femoris muscle (QFM) before and after birth. Part I. Rectus femoris muscle (RFM)

Studies on the formation of morphological traits of the quadriceps femoris muscle were carried out on the material of 138 human fetuses (70 males and 68 females), 9-36 weeks old, and 50 adults (33 male, and 17 female). Some intermediary conclusions were drawn for probable changes occurring in the morphological formation of the muscle after birth by comparing proportions of the muscle at the fetal stage with its form in adults. In this research, anthropometric methods and statistical analysis of results have been applied. The analysis of the results in the fetal group has shown that all metrical characteristics of the muscle reach their maximum values at the end of the investigated ontogenetic period. This is, naturally, a consequence of the development and growth of all fetal body measures, including an elongation of the thigh. Yet, the development of the individual muscle characteristics is not regular and although the trend of this growth is similar, its extent varies, and differs slightly in the two sexual groups. A comparison of the values of muscle indices for 9 month old fetuses with the same indices for adults shows that the relative dimensions of all investigated muscular characteristics decrease during the post-natal period except the relative length of the tendon.

[Evaluation of blood rheology indices in patients with pheochromocytoma]

Investigated group consisted of 28 patients (21 female and 7 male) with pheochromocytoma in mean age of 39.9 +/- 13 years, while control group comprised 25 healthy volunteers in mean age 36.0 +/- 7.2 years. Following parameters were determined: plasma and blood viscosity, erythrocyte and platelets aggregation, erythrocyte deformability, hematocrit, beta-thromboglobulin plasma concentration, plasma fibrinogen concentration, lipids concentration, noradrenaline, adrenaline, serotonin, neuropeptide Y plasma concentrations. Plasma fibrinogen and beta-thromboglobulin were increased in pheochromocytoma before surgery after pharmacological treatment and also after excision of the tumor. Whereas altered erythrocyte deformability before any treatment, only. Plasma neuropeptide Y concentration was higher in pheochromocytoma before surgery and after pharmacological treatment. There was no correlation between plasma catecholamines, plasma fibrinogen, beta-thromboglobulin, and erythrocyte deformability. Our results suggest that rheological abnormalities observed in patients with pheochromocytoma may contribute to vascular complications in this subjects. Sympathetic nervous system seems to influence indirectly observed rheological abnormalities.

Endothelin-1 and neuropeptide Y plasma concentrations in renal venous blood of hypertensive patients with unilateral renal artery stenosis

The aim of the study was to investigate endothelin-1 (ET-1) and neuropeptide Y (NPY) plasma concentrations in renal venous blood of hypertensive patients with unilateral renal artery stenosis (URAS). The study was performed in 22 patients with URAS and 18 patients diagnosed as essentially hypertensive. In each subject renal arteriography and renal vein catheterisation was performed. Blood samples for ET-1, NPY and plasma renin activity (PRA) were withdrawn from renal veins and vena cava inferior, and for ET-1 and NPY from the aorta. Patients with URAS were divided in two subgroups according to the renal vein renin ratio. Both in nine patients with URAS and ratio > 1.5 and in 13 patients with URAS and ratio < 1.5, ET-1 and NPY plasma concentrations evaluated in renal venous blood of the ischaemic kidney were not different from those assessed in the contralateral side, in vena cava inferior and in the aorta. In essential hypertension, the mean ET-1 and NPY plasma concentrations of both renal veins were not different from the ET-1 and NPY plasma values assessed in renal vein of stenosed and contralateral side, vena cava and aorta of patients with URAS with and without activation of the renin system. Our study indicates that chronic ischaemia does not affect ET-1 and NPY plasma concentrations in renal venous blood of hypertensive URAS patients both with and without activation of the renin system.

Postural stimulation test in patients with aldosterone producing adenomas

OBJECTIVE

The purpose of this study was to evaluate the postural stimulation test before and after surgical treatment in patients with aldosterone-producing adenomas.

DESIGN

The retrospective study was made on patients with aldosterone producing adenomas.

PATIENTS

The postural stimulation test was analysed in 60 patients with surgically proven aldosterone producing adenoma and in 15 healthy volunteers.

MEASUREMENTS

The postural stimulation test was based on measurements of plasma aldosterone, cortisol and renin activity (PRA) at 0800 h and at noon after 4 hours ambulation.

RESULTS

The patients were divided into two groups according to the individual pattern of plasma aldosterone concentration following the postural test. Plasma aldosterone concentration decreased or did not change after 4 hours of standing in 42 patients (group 1, 70% of total) and increased in 18 patients (group 2, 30% of total). Mean plasma aldosterone was significantly higher in group 1 than in group 2 (1325 +/- 164 pmol/l (mean +/- SE) and 538 +/- 53 pmol/l, respectively). Mean plasma cortisol concentration after 4 hours of upright posture in both groups remained low (242 +/- 35 vs 401 +/- 63 nmol/l (group 1) and 317 +/- 46 vs 367 +/- 43 nmol/l (group 2)). Mean PRA in both groups was suppressed after 4 hours of upright posture (0.2 +/- 0.04 vs 0.2 +/- 0.04 pmol/l/s and 0.3 +/- 0.06 vs 0.1 +/- 0.02 pmol/l/s, respectively).

CONCLUSION

Diverse changes in plasma aldosterone and cortisol found in response to the postural test may indicate pathogenetic heterogeneity amongst patients with aldosterone producing adenomas and should be considered during diagnosis of primary aldosteronism.

[A case of thrombosis of the portal vein treated conservatively]

Portal vein thrombosis is a difficult diagnostic and therapeutic problem. The predominating clinical sign of isolated portal vein thrombosis is usually a haemorrhage from oesophageal varices. A case is presented of portal vein thrombosis without the above mentioned sign, treated conservatively with good effect. The importance is worth stressing of abdominal USG examination in early diagnosis of the described disease.

Lateral shear interferometer for infrared and visible light

An infrared wavefront is recorded holographically on a dynamic recording medium consisting of a thin oil film on a glass substrate. The phase hologram obtained may restore the information of the infrared wavefront or alternatively play the role of a diffraction grating for a visible reconstruction beam. On this basis, the principle of a lateral shear interferometer for the simultaneous testing of infrared or visible optical components is described and physically implemented. A theoretical discussion explains the operation of the interferometer and points out experimental restrictions due to recording medium nonuniformities, holographic aberrations, and the curvature of the reconstructed wavefronts. The interferometer is easy to set up and confirms its usefulness with experimental results that include collimation tests for both visible and infrared afocal assembly, as well as quality tests for visible components.

[Neonatal blood aldosterone]

Postnatal aldosterone levels have been studied in 13 newborns from birth to the end of the 3rd day of life. The examinations were performed in children in whom blood samples were collected frequently for the clinical reasons (mostly because of suspected serologic incompatibility). Aldosterone level was measured by radioimmunoassay in the mixed cord blood and then at 2, 6, 12, 48, 72 hours after birth. Aldosterone concentration in the cord blood was 0.35 ng/dl and rapidly increased to 0.79 ng/dl during the first two hours after birth. The same value was obtained at the 6th hour of life. The mean aldosterone concentrations were 0.85 ng/dl at the 12th hour, 0.89 ng/dl at the 24th and 48th and 0.85 at the 72nd hour of life. Postnatal variation of aldosterone levels differs from previously investigated variations of glucocorticoids levels.

Use of the leukocyte esterase and nitrite tests to determine the need for culturing urine specimens from a pediatric and adolescent population

Using a commercially available dip stick 601 urine specimens were screened for leukocytes and bacteria by testing for the presence of leukocyte esterase and nitrite. The screening method was found to have a sensitivity of 88.7% and a predictive value of negative results of 98.5%.