Urocortin 2 - a protective effect in hypertension?

Urocortin 2, an endogenous selective ligand for the corticotropin-releasing hormone receptor type 2, has been suggested to exert cardioprotective effects. We analyzed the possible relationship between the level of Ucn2 and specific indicators of cardiovascular risk factors in patients with untreated hypertension and in healthy subjects. Sixty seven subjects were recruited: 38 with newly diagnosed treatment-naive hypertension (with no pharmacological treatment - HT group) and 29 healthy subjects without hypertension (nHT group). We evaluated ambulatory blood pressure monitoring, Ucn2 levels and metabolic indices. Multivariable regression analyses were performed to assess the effects of gender, age, and Ucn2 levels on metabolic indices or blood pressure (BP) level. Log of Ucn2 levels were higher in healthy subjects than in hypertensive patients (2.44±0.7 versus 2.09±0.66, p<.05) and correlated inversely with 24-hour diastolic blood pressure, and both night-time systolic and diastolic blood pressure regardless of age and gender (R2=0.06; R2=0.06; R2=0.052; respectively). Furthermore, Ucn2 levels inversely correlated with cholesterol and low-density cholesterol (LDL) concentrations in healthy subjects only. Ucn2 was independently related to total cholesterol (but not to LDL) regardless of age, gender and the presence of hypertension (R2=0.18). However, we did not find any relationship between urocortin 2, body mass index or waist-hip ratio as well as parameters of glucose metabolism. Our data indicates that higher levels of urocortin 2 are related to more favorable lipid profiles and lower blood pressure.

Urocortin 2 - a protective effect in hypertension?

Urocortin 2, an endogenous selective ligand for the corticotropin-releasing hormone receptor type 2, has been suggested to exert cardioprotective effects. We analyzed the possible relationship between the level of Ucn2 and specific indicators of cardiovascular risk factors in patients with untreated hypertension and in healthy subjects. Sixty seven subjects were recruited: 38 with newly diagnosed treatment-naive hypertension (with no pharmacological treatment - HT group) and 29 healthy subjects without hypertension (nHT group). We evaluated ambulatory blood pressure monitoring, Ucn2 levels and metabolic indices. Multivariable regression analyses were performed to assess the effects of gender, age, and Ucn2 levels on metabolic indices or blood pressure (BP) level. Log of Ucn2 levels were higher in healthy subjects than in hypertensive patients (2.44±0.7 versus 2.09±0.66, p<.05) and correlated inversely with 24-hour diastolic blood pressure, and both night-time systolic and diastolic blood pressure regardless of age and gender (R2=0.06; R2=0.06; R2=0.052; respectively). Furthermore, Ucn2 levels inversely correlated with cholesterol and low-density cholesterol (LDL) concentrations in healthy subjects only. Ucn2 was independently related to total cholesterol (but not to LDL) regardless of age, gender and the presence of hypertension (R2=0.18). However, we did not find any relationship between urocortin 2, body mass index or waist-hip ratio as well as parameters of glucose metabolism. Our data indicates that higher levels of urocortin 2 are related to more favorable lipid profiles and lower blood pressure.

Predicting silent atrial fibrillation in the elderly – NOMED-AF study

Background

Asymptomatic (“silent”) atrial fibrillation is common and associated with poor outcomes. It is important to determine the risk factors that predispose elderly individuals from the general population to atrial fibrillation (AF). However, population-based data for silent AF (SAF) are limited.

Design

First, to study the risk factors for symptomatic AF and SAF in an elderly (≥65 years) general population. Second, to develop a risk stratification model for predicting SAF.

Methods

Continuous ECG monitoring was performed for up to 30 days using a vest-based system in a cohort from NOMED-AF, a cross-sectional study based on a nationwide population sample. The independent risk factors for AF and SAF were determined using multiple logistic regression. ROC analysis was applied to validate developed risk stratification score.

Results

From the total cohort of 3014 subjects, AF was diagnosed in 680 individuals (mean age, 77.5±7.9; 50.1% men) with AF, and of these, 279 (41%) had SAF. Independent associations with an increased risk of AF were age, male gender, coronary heart disease, thyroid diseases, prior ischemic stroke or transient ischemic attack (ICS/TIA), diabetes, heart failure, chronic kidney disease (CKD), obesity (BMI&gt;30) and NT-proBNP &gt;125 ng/ml. Prior revascularization was negatively associated with risk of AF.

The main risk factors for SAF were age, male gender, prior ICS/TIA, diabetes, heart failure, CKD and NT-proBNP &gt;125 ng/ml.

We developed a simple clinical risk scale (MR-DASH score) which had good prediction in the derivation cohort (AUC 0.726) and the validation cohort (AUC 0.730).

Conclusions

SAF is associated with various clinical risk factors in a population sample of individuals ≥65 years. Stratifying individuals from the general population according to their risk for SAF may be possible using the MR-DASH score, facilitating targeted screening programs of individuals with high risk of SAF

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National Centre for Research and Development

Risk factors for silent and symptomatic atrial fibrillation in an elderly population screening programme:a report from the noninvasive monitoring for early detection of atrial fibrillation (NOMED-AF)

Background

It is important to determine the risk factors that predispose elderly subjects from the general population for symptomatic atrial fibrillation and atrial flutter (AF/AFl), but population-based data for silent AF (SAF) are limited.

Aim

To study risk factors for symptomatic AF and SAF in a general population screen for subjects age ≥65 where continuous monitoring was performed up to 30 days with a vest-based monitor.

Methods

The NOMED-AF study was a cross-sectional study based on a representative population sample (n=3014; mean age 77.5±7.9 years; F=1479). In 680 subjects AF/AFl (including 279 with SAF) was diagnosed. Independent risk factors for AF/AFl and SAF were determine on weighted data using multiple logistic regression.

Results

The independent risk factors for AF/AFl and SAF are summarised in the Table. There are nine independent risk factors for AF/AFl and eight for SAF. Revascularization and obesity were independently associated with patients with (symptomatic) AF/AFl, and CKD was associated with SAF. Other risk factors are common for AF/AFl and SAF.

Conclusions

AF/AFl and SAF have slightly different associated clinical risk factors in this representative population sample aged ≥65 years. This may facilitated targeted screening programmes for high risk subgroups, particularly for SAF.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The research has received funding from the National Centre for Research and Development under grant agreement (STRATEGMED2/269343/18/NCBR/2016)

Screening for atrial fibrillation in subjects aged 65 using a long-term continuous ECG telemonitoring vest: the NOninvasive Monitoring for early detection of atrial fibrillation (NOMED-AF) study

Background

Atrial fibrillation (AF) confers a high healthcare burden from stroke, heart failure, dementia and hospitalisation, and one challenge is. Early detection of this arrhythmia in the community, given that it is often asymptomatic.

Aim

To perform population screening for atrial fibrillation and flutter (AF/AFl) using a mobile long-term continuous ECG telemonitoring vest in a representative Polish and European population aged ≥65 years (age range 65–100 years).

Methods

The NOMED-AF study is a cross-sectional study based on a representative sample of adults aged ≥65 years (n=3014; mean age 77.5±7.9 years; 49.1% female). All study participants were equipped with a mobile long-term continuous ECG telemonitoring vest. National and European estimations were calculated on weighted data.

Results

In 680 subjects AF/AFl (including 279 with SAF; 9.3%) was confirmed. In the NOMED-AF population, the prevalence of AF/AFl was 22.6%, estimated to be 19.2% for Poland [1,251,100 (95% CI: 1,158,300–1,344,000) and 480,100 (95% CI: 426,60–533,700) subjects with AF/AFl and SAF, respectively] and 20.4% for Europe [20,300,000 (95% CI 18.8–21.9 M), including 8,000,000 (95% CI: 6.9–9.3 M) subjects with AF/AFl and SAF, respectively]. The prevalence of AF/AFl was 2.56-fold higher in men than in women and the incidence of silent AF (SAF) was 4.73-fold higher in men than in women. Although the risk of either AF/AFl or SAF increased with age, the odds ratio was significantly higher in women of a particular age group than in men of the corresponding age. Based on our survey, the total number of subjects with AF/AFl in Europe is estimated to be roughly 20.3 million (95% CI 18.8–21.9M), including 8.0 million (95% CI: 6.9–9.3M) subjects with silent AF/AFl (Figure).

Conclusions

Approximately 1 in 5 subjects aged ≥65 years suffers from AF/AFl. The risk for AF/AFl and SAF is higher in men than that in women, but when correlated to a particular age group, the risk increases significantly in women. Continuous ECG telemonitoring allows for more credible AF/AFl and SAF detection.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): The research has received funding from the National Centre for Research and Development under grant agreement (STRATEGMED2/269343/18/NCBR/2016

Arterial structure and function and its short- and long-term changes after bariatric surgery

Subclinical arterial damage connected with endothelial dysfunction is a common denominator of cardiovascular complications in a variety of metabolic diseases, including obesity. The aims of the study was to assess functional vascular changes measured by flow-mediated dilatation (FMD) and nitroglycerin-mediated dilation (NMD) of brachial artery, and to measure vascular structural alterations estimated by carotid intima-media complex thickness (IMT) in short- (10 days) and medium-term (6 months) time after bariatric surgery in patients with extreme obesity. Anthropometric, blood pressure (BP), FMD, NMD, IMT measurements, and laboratory assessment were performed on patients who met the eligibility criteria for bariatric surgery (age 18 - 60 years old, BMI ≥ 40.0 kg/m² or with BMI 35.0 - 39.9 kg/m² and co-morbidities), at baseline and during follow-up. The study population consisted of 71 patients: mean SD aged 45.6 (± 10.9) years; BMI = 47.7 (± 6.1) kg/m²; 45% of them were men). A significant reduction of systolic BP, glucose, HDL cholesterol, leptin, insulin and HOMA-IR were observed 10 days post intervention. A significant increase of FMD values was observed in the entire group 6 months after surgery (median (IQR) 6.2 (2.9 - 10.3) versus 8.5 (6.1 - 16.6), P < 0.05). Changes of NMD were insignificant. Carotid IMT diminished significantly after 6 months (median (IQR) 0.6 (0.5 - 0.7) versus 0.6 (0.5 - 0.6) mm, P < 0.05). A subgroup analysis revealed that FMD parameters had improved significantly after 6 months, mainly in men, hypertensives, and in the Roux-en Y bypass (RYGB) subgroup. In conclusion, endothelial function and subclinical atherosclerosis improved after bariatric surgery in patients with extreme obesity. A lack of changes of the dilatation independent of endothelial function may indicate the persistence of residual changes in the vascular bed.

Urocortin 2 in patients with hypertension treated with angiotensin converting enzyme inhibitors or angiotensin receptor blockers

Urocortin 2 (Ucn2) - corticotropin-releasing hormone receptor 2 signalling has favourable effects in the cardiovascular system, including vasodilation, lowering of blood pressure and systemic peripheral resistance, increase in cardiac output and cardiac contractility, as well as cardioprotection against ischemia-reperfusion injury. Vasodilation and lowering of blood pressure seem to be very interesting and important effects, but their mechanism and interaction with the antihypertensive drugs have not been evaluated. The aim of the present study was to assess the relationship between Ucn2 concentration and antihypertensive therapy in patients with primary hypertension. We examined a group of 65 patients with primary hypertension receiving at least 3 antihypertensive drugs. In all of them plasma level of Ucn2, anthropometric measurements, biochemical tests, ambulatory blood pressure monitoring (ABPM), and echocardiography were performed. There were no differences in Ucn2 level related to beta-blockers, calcium channel blockers or diuretics, but we observed that in patients treated with angiotensin converting enzyme inhibitors (ACEI) (n = 52) serum Ucn2 levels were significantly higher than in patients treated with angiotensin-receptor blockers (ARBs) (n = 13) (10.93 versus 5.56 ng/mL; P < 0.05). Moreover, we did not observe any differences in terms of blood pressure on ABPM, biochemical measurements, left ventricular mass index, or presence of diabetes. In addition, in a small subgroup receiving alpha-blockers we also found a lower level of Ucn2, with coexisting higher systolic blood pressure at night, higher left ventricle mass index (LVMI) and more frequent occurrences of diabetes compared to non-alpha-blockers. Our findings suggest that the hypotensive action of renin-angiotensin-aldosterone system blockade may be related to the urocortin system. Ucn2 may be an important element in the mosaic of blood pressure-lowering factors in patients treated for essential hypertension.

Effects of controlled physical activity on immune cell phenotype in peripheral blood in prehypertension - studies in preclinical model and randomised crossover study

Hypertension (HT) is a global public health issue. There are many behavioural risk factors including unhealthy diet, tobacco use and alcohol consumption as well physical inactivity that contribute to the development of high blood pressure (BP) and its complications. Favourable effect of regular physical activity on treatment or prevention of hypertension by improvement of endothelial function is widely accepted however little is known about its relationship with immune system. Thus, the aim of this study was to assess the role of moderate regular physical activity on immune cell phenotype. T cell and monocyte subsets were characterised in 31 subjects with prehypertension (130 - 139 mmHg systolic and 85 - 89 mmHg diastolic blood pressure) who participated in moderate training (3 times/week) on cyclometers for 3 months in crossover study design. Complementary study was performed in murine model of Ang II-induced hypertension and ten-week-old animals were trained on a treadmill (5 times/week, 1 hour) for 2 weeks before and 1.5 weeks after minipumps implantation. In the context of elevated blood pressure regular physical activity had modest influence on immune cell phenotype. Both in human study and murine model we did not observe effects of applied exercise that can explain the mechanism of BP reduction after short-term regular training. Twelve-weeks regular training did not affect the activation status of T lymphocytes measured as expression of CD69, CD25 and CCR5 in human study. Physical activity resulted in higher expression of adhesion molecule CD11c on CD16+ monocytes (especially CD14 high) without any changes in leukocytes subpopulation counts. Similar results were observed in murine model of hypertension after the training. However the training caused significant decrease of CCR5 and CD25 expressions (measured as a mean fluorescence intensity) on CD8+ T cells infiltrating perivascular adipose tissue. Our studies show modest regulatory influence of moderate training on inflammatory markers in prehypertensive subjects and murine model of Ang II induced hypertension.

Controlled aerobic training improves endothelial function and modifies vascular remodeling in healthy adults with high normal blood pressure

The aim of the study was to assess endothelial function in adults with high normal blood pressure (HNBP) undergoing controlled aerobic training. The study was conducted among 31 volunteers with HNBP. Subjects underwent supervised cycle ergometer training for 12 weeks. Exercise intensity was assessed by monitoring the pulse with intention to keep the heart rate increase within the range of 40% to 65% of the heart rate reserve. The control group consisted of 14 healthy adults, not subjected to any intervention. The control group was examined twice at 12-week intervals (non-exercising time control). Vascular endothelial function was determined by flow-mediated dilation (FMD) and by measuring total nitric oxide products (NOx). The measurement of carotid intima-media complex thickness (IMT) was an indirect method of assessing vascular remodeling. Blood pressure (ABPM method), anthropological parameters and lipid profile were also assessed. There was a significant change in FMD after 3-month training in the study group: the average FMD training was 5.21 ± 2.17%, while after the program FMD increased to 9.46 ± 3.69% (P < 0.001). After training, the NO_x also increased from 1.01 ± 0.38 μmol/L to 1.27 ± 0.48 μmol/L (P < 0.001). Effects were observed irrespective of participants' sex. Interestingly, a modest but significant reduction of IMT was also observed, from 0.5 ± 0.06 mm to 0.46 ± 0.10 mm (P = 0.04). There was also a reduction in the percentage of body fat content from 25.01 ± 8.77% to 22.31 ± 8.79% (P < 0.001). No statistically significant changes were noted after 12 weeks of training in the blood pressure and lipid profile. In the control group no statistically significant changes of any parameter were observed. Regular aerobic exercise improves nitric oxide-dependent endothelial function of the vessels and can initiate regression of atherosclerosis in people with HNBP.

Influence of Sociodemographic, Behavioral and Other Health-Related Factors on Healthy Ageing Based on Three Operative Definitions

OBJECTIVES

Healthy ageing (HA) is a key concept and highly desirable phenomenon in every ageing and already old societies. The aim of our study was to evaluate the influence of socio-economic conditions as well as life-style and other health-related factors on the WHO definition of HA.

DESIGN, SETTING, PARTICIPANTS

The study used cross-sectional data of the PolSenior Project - nationwide research evaluating different aspects of ageing in Poland - which included 4'653 respondents aged 65 years and over.

MEASUREMENTS

Data were collected by trained interviewers in respondents' homes. Three definitions of HA including or not the participants' chronic conditions were analyzed.

RESULTS

The prevalence of HA appeared as high as 17.6% if none or 1 chronic disease was present and 42.8% if no information about chronic diseases was taken into account. The association between known health predictors (age, marital status, education, income) and HA was observed. Moreover, HA appeared in relation with indicators of physical functioning and lifestyle. There was a strong concordance between HA and the fair self-rated health (OR = 1.87; 1.99, and 2.74 for the 1st, 2nd and 3rd definitions, respectively) and opposite relation with self-reported need for help (OR = 0.15; 0.15; and 0.13, respectively).

CONCLUSIONS

The HA definition based on no functional activity limitations, no cognitive impairment, no depressive symptoms, no more than one disease and being socially active seems to be a useful approach of HA.

Components of metabolic syndrome in relation to plasma levels of retinol binding protein 4 (RBP4) in a cohort of people aged 65 years and older

PURPOSE

Elevated plasma concentration of retinol binding protein 4 (RBP4) has recently emerged as a potential risk factor as a component of developing metabolic syndrome (MS). Therefore, this study aimed to analyse the relationship between components of MS and concentrations of plasma RBP4 in a population of subjects 65 years and older.

METHODS

The study sample consisted of 3038 (1591 male) participants of the PolSenior study, aged 65 years and older. Serum lipid profile, concentrations of RBP4, glucose, insulin, C-reactive protein, IL-6, and activity of aminotransferases were measured. Nutritional status (BMI/waist circumference) and treatment with statins and fibrates were evaluated. Glomerular filtration rate (eGFR), de Ritis ratio, and fatty liver index (FLI), as well as HOMA-IR were calculated.

RESULTS

Our study revealed a strong relationship between components of MS and RBP4 in both sexes: plasma RBP4 levels were increased in men by at least 3×, and in women by at least 4×. Hypertriglyceridemia was most strongly associated with elevated plasma RBP4 levels. Multivariate, sex-adjusted regression analysis demonstrated that chronic kidney disease [OR 1.86 (95% CI 1.78-1.94)], hypertriglyceridemia [OR 1.52 (1.24-1.87)], hypertension [OR 1.15 (1.12-1.19)], low serum HDL cholesterol [OR 0.94 (0.92-0.97)], and age > 80 years [OR 0.86 (0.81-0.90)] were each independently associated with RBP4 concentration (all p < 0.001).

CONCLUSIONS

In Caucasians 65 years and older, RBP4 serum levels are associated with a number of components of MS, independent of sex and kidney function. Hypertriglyceridemia as a component of MS is most significantly related to RBP4 concentration.

Atrial fibrillation independently linked with depression in community-dwelling older population. Results from the nationwide PolSenior project

BACKGROUND

Depression is a frequently observed comorbid condition in patients with cardiovascular diseases. In contrast to coronary heart disease and heart failure there is a limited amount of published data concerning the increased prevalence of depression among patients with atrial fibrillation (AF). Therefore, we decided to assess the prevalence of depression in Polish community-dwelling older patients with a history of AF.

METHODS

The data were collected as part of the nationwide PolSenior project (2007-2012). Out of 4979 individuals (age range 65-104 years), data on self-reported history of AF were available for 4677 (93.9%). Finally, 4049 participants without suspected moderate or severe dementia in Mini Mental State Examination test were assessed with the 15-item Geriatric Depression Scale (GDS), and a score of 6 points and more was regarded as suspected depression.

RESULTS

Mean age (±SD) of the study population was 78.1 (±8.3) years; 52% were males. The history of AF was reported by 788 (19.5%) subjects. In the univariate analysis a self-reported AF history was associated with 42% increase of suspected depression (41% vs 29%; P < 0.001). In multivariate logistic regression AF remained an independent predictor of depression (OR = 1.69; 95%CI: 1.43-2.00), stronger than heart failure, diabetes or coronary heart disease.

CONCLUSIONS

In community-dwelling geriatric Polish population AF is associated with higher prevalence of depression. This association is independent from the demographic factors, disabilities and comorbidities (including history of stroke).

Multifractal characterization of morphology of human red blood cells membrane skeleton

The purpose of this paper is to show applicability of multifractal analysis in investigations of the morphological changes of ultra-structures of red blood cells (RBCs) membrane skeleton measured using atomic force microscopy (AFM). Human RBCs obtained from healthy and hypertensive donors as well as healthy erythrocytes irradiated with neutrons (45 μGy) were studied. The membrane skeleton of the cells was imaged using AFM in a contact mode. Morphological characterization of the three-dimensional RBC surfaces was realized by a multifractal method. The nanometre scale study of human RBCs surface morphology revealed a multifractal geometry. The generalized dimensions Dq and the singularity spectrum f(α) provided quantitative values that characterize the local scale properties of their membrane skeleton organization. Surface characterization was made using areal ISO 25178-2: 2012 topography parameters in combination with AFM topography measurement. The surface structure of human RBCs is complex with hierarchical substructures resulting from the organization of the erythrocyte membrane skeleton. The analysed AFM images confirm a multifractal nature of the surface that could be useful in histology to quantify human RBC architectural changes associated with different disease states. In case of very precise measurements when the red cell surface is not wrinkled even very fine differences can be uncovered as was shown for the erythrocytes treated with a very low dose of ionizing radiation.

Human monocyte subsets exhibit divergent angiotensin I-converting activity

Immune cells may take part in the renin-angiotensin-aldosterone system (RAAS), which plays a pivotal role in the regulation of vascular tone and blood pressure. The aim of the study was to analyse the expression and activity of angiotensin-converting enzyme type 1 (ACE1) and ACE2 in human monocytes (MO) and their subsets. The highest relative level of ACE1-, as well as ACE2-mRNA expression, was observed in CD14(++)CD16(-) (classical) MO. Moreover, in these cells, mean level of ACE2-mRNA was almost two times higher than that of ACE1-mRNA (11.48 versus 7.073 relative units, respectively). In peripheral blood mononuclear cells (PBMC), MO and classical MO, ACE1 and ACE2 protein expression was stronger compared to other MO subpopulations. The highest level of Ang II generated from Ang I in vitro was observed in classical MO. In this setting, generation of Ang-(1-9) by PBMC and classical MO was higher when compared to the whole MO population (P < 0.05). The generation rate of vasoprotective Ang-(1-7) was comparable in all analysed cell populations. However, in CD14(+)CD16(++) (non-classical) MO, formation of Ang-(1-7) was significantly greater than Ang II (P < 0.001). We suggest that in physiological conditions MO (but also lymphocytes forming the rest of PBMC pool) may be involved in the regulation of vessel wall homeostasis via the RAAS-related mechanisms. Moreover, non-classical MO, which are associated preferentially with the vascular endothelium, express the vasoprotective phenotype.

The role of urocortins in the cardiovascular system

Urocortins (Ucn) 1, 2 and 3 are a group of endogenous peptide hormones belonging to the corticotropin-releasing hormone (CRH) family of peptides. The presence of urocortins has been detected in the central nervous system as well as in peripheral tissues. They play an important role in a stress response (with respect to its duration, intensity and restoration of homeostasis). They also act as regulatory factors of the cardiovascular, gastrointestinal, reproductive and immune systems. Urocortins act by binding to G-protein-coupled receptors (GPCR). The "central" effects of urocortins are mediated mainly by activation of CRH receptor 1 (CRH-R1), and the "peripheral" effects by activation of CRH-R2. Ucn2 and Ucn3 are selective CRH-R2 agonists and have much higher binding affinity to this receptor than CRH and Ucn1. Recent studies have shown that urocortins exert various biological effects in the cardiovascular system, such as vasodilation, positive inotropic and lusitropic effects, as well as cardioprotection against ischemia-reperfusion injury. They also suppress the renin-angiotensin system and may have an impact on the sympathetic nervous system. Urocortins and CRH-R2 may be a potential therapeutic target in coronary heart disease, congestive heart failure and hypertension. This review summarizes the data published to date on the role of urocortins in the cardiovascular system.

Yttrium-90 distribution following radiosynoviorthesis of the knee joint in rheumatoid arthritis patients: a SPECT/CT study

Objective

To examine yttrium-90 distribution 1 and 72 h following its injection into a knee joint in patients with rheumatoid arthritis (RA).

Methods

In 14 RA patients we injected yttrium-90 into the affected knee joint using lateral approach. To assess the radioisotope distribution in the joint, the superimposed sequential SPECT and CT imaging was performed 1 and 72 h after the injection. We analyzed the percentage of radioisotope distribution in three predefined compartments of the knee joint (lower, upper medial, upper lateral).

Results

After 1 and 72 h, the mean percentage distributions were, respectively, 7.14 and 23.07 % in lower; 21.42 and 15.38 % in upper medial, and 71.42 and 61.53 % in upper lateral compartment. The percentage of isotope deposition did not change significantly with time in any of the compartments (all p > 0.26). The deposition of isotope, both at 1 and 72 h, was significantly greater in upper lateral compartment, where the injection was performed, than in all other compartments (all p < 0.05).

Conclusions

Using the SPECT/CT hybrid method, we proved that the majority of isotope is located at the compartment adjacent to the injection. Two injections targeting different compartments might improve the clinical efficacy of the procedure.

Chemical composition and inherent properties of offal from calves maintained under two production systems

The aim was to evaluate the influence of organ and calf type on the chemical composition, mineral concentration, fatty acid profile and inherent properties in offal. Organ type influenced (p<0.01) all evaluated characteristics, whereas calf type to a lesser extent affected mineral content. The highest contents of K, Zn and Fe were found in liver. The heart of veal calves contained the highest contents of Mg and Mn. In addition, the most favorable fatty acid profile was also found in hearts, by reason of the lowest SFA and highest PUFA percentage and h/H ratio. Significantly higher values of PUFA percentage, PUFA/SFA ratio, and content of CLA were found in organs of suckler beef, which is associated with the beneficial effects of grazing on the fatty acid profile. Results could help to increase the consumption of calves' offal and its utilization in meat processing.

Neurogenic and myogenic resting skin blood flowmotion in subjects with masked hypertension

The aim of our study was to investigate, whether masked hypertension (MH) and sustained hypertension (HT) are associated with alteration of resting skin blood flow and flowmotion. Subjects recruited to the study were assigned to three groups according to the results of blood pressure (BP) measurements. Resting blood flow (RF) and an index of cutaneous vascular conductance (CVC), were measured by Laser Doppler Flowmetry (LDF). Total power of the studied interval and five subintervals related to: endothelium, sympathetic, myogenic, respiration and heart activity, were analyzed. Serum glucose, sodium level, lipid profile, as well as insulin, endothelin and norepinephrine levels were measured. The study population consisted of 82 persons: 29 NT, 17 MH and 36 HT. There were no differences between the study groups with respect to age and gender, but they significantly differed with respect to body mass index (p=0.04) and waist circumference (p=0.02), triglyceride levels (p=0.04; highest in HT group), norepinephrine levels (p=0.01; highest in MH group). RF as well as CVC RF were similar in NT, MH and HT groups. Power spectrum of sympathetic origin was significantly different in the study groups (p=0.03), with highest values in MH group. Moreover, the subjects with MH revealed increased power spectrum of myogenic activity, both absolute (p=0.05) and relative (p=0.08). Daytime systolic BP was the most consistent predictor of sympathetic and myogenic origin of elevated skin blood flowmotion in multiple regression models. Our findings suggest that subjects with MH revealed altered microcirculation with elevated resting flowmotion of sympathetic and myogenic origin.

Physicochemical properties of milk fat from three breeds of cows during summer and winter feeding

Abstract. The investigations included total 515 milk samples which were collected from 309 cows of the main dairy cows’ breeds used in Poland, i.e. Polish Holstein-Friesian Black-White variety (n=150), Polish Holstein-Friesian Red-White variety (n=77) and Simmental (n=82). There was determined a content of fat, protein and dry matter, a share of fat globules ranging in size, i.e. <6 μm, 6-10 μm and >10 μm as well as a fatty acids profile. It was shown that milk gained from Holstein-Friesian cows was characterized with a higher level of fat dispersion (over 70 % globules of <6 μm diameter and a higher percentage of short- and long-chain fatty acids (ca. 19 %). The Simmentalers’ milk had a higher protein : fat ratio (about 0.89), a lower fat dispersion level (8.21 % globules of >10 μm diameter) and the highest share of the polyunsaturated fatty acids (3.28 %). Cows nutrition included pasture forage during summer (independently on the breed) had a significant influence (P≤0.01) on increased polyunsaturated fatty acids percentage (mean by 0.51 %). The winter milk, however, showed a significantly higher content of dry matter, fat and protein as well as a higher share of big-sized milk globules.

Rheological properties of erythrocytes in patients with high risk of cardiovascular disease

Rheological properties of erythrocytes from patients with high risk of cardiovascular disease (CVD) were analyzed in relation to individual patient risk factors as well as to the medication. Additionally, comparative statistical analysis was performed considering plasma concentration of the selected mediators of vascular endothelium: 6-keto-prostaglandin F(1alpha) (PGF(1alpha)), sVCAM-1 and E-selectin adhesion molecules and interleukin-6 (IL-6). It was found that antihypertensive therapy with angiotensin-converting enzyme inhibitor (ACEI) is accompanied by improvement of RBC rheology: the increase of deformability and the decrease of aggregability. This improvement is probably mediated by endothelial prostacyclin and nitric oxide which are generated by ACEI. A correlation was observed between RBC deformability/aggregability and the patient's hematocrit level, what implicates that the hematocrit level should be explicitly taken into consideration when investigating rheological properties of erythrocytes. A strong relationship was also found between the plasma concentration of sVCAM-1 and patient's age.