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The reductive catalytic fractionation (RCF) of lignocellulosic biomass is an attractive method for the conversion of lignin toward valuable low-molecular weight aromatics. A limitation to the upscaling of such technology is represented by the use ofpressurized hydrogen gas. Here, the role of hydrogen gas within the RCF of wheat straw biomass is investigated. The use of H 2 is shown to enhance lignin depolymerization, by virtue of an improved hydrogenolysis and hydrogenation of lignin fragments, with a yield of phenolic monomers that increased from ca. 12 wt % of acid-insoluble lignin in the initial biomass under inert atmosphere to up to ca. 25 wt % under H 2 (in methanol, at 250 °C, with Ru/C). The adoption of methanol, ethanol or isopropanol as hydrogen-donor solvents was also investigated in the absence of H 2 . Ethanol was found to give the highest yield of monophenolic compounds (up to ≈20 wt %) owing to a better balance between solvolysis, hydrogenolysis, and hydrogenation of lignin. Nevertheless, a substantial loss of the carbohydrate fraction was observed. The use of a lower temperature (200 °C) in combination with H 3 PO 4 resulted in an improved recovery of cellulose in the pulp and in the solubilization of hemicellulose and lignin, with the formation of monosaccharides (≈14 wt % of polysaccharides in the initial biomass) and phenolic monomers (up to 18 wt %, in the absence of H 2 ). Overall, a tradeoff exists between the removal of H 2 from the process and the production of low-molecular weight phenolics during RCF., (© 2023 Wiley-VCH GmbH.)

Abiotic stress conditions, such as salinity, affect plant development and productivity and threaten the sustainability of agricultural production. Salt has been proven to accumulate in soil and water over time as a result of various anthropogenic activities and climatic changes. Species of the genus Salicornia thrive in the most saline environments and have a wide climatic tolerance. They can be found in a variety of subtropical, oceanic, and continental environments. This study aims to establish Salicornia europaea as a novel source of plant-based compounds that can grow in areas unsuitable for other crops. The morphological and compositional changes in the tissues of S. europaea in different consecutive developmental stages have not been investigated so far. Therefore, a comprehensive study of changes during the lifecycle of S. europaea was carried out, following changes in the plant's composition, including biomass yield, and soluble and insoluble compounds. For this, plants were cultivated in hydroponics for 15 weeks and harvested weekly to analyze biomass production, to determine soluble and insoluble compounds, protein content, and polyphenols. According to the results, glucan, xylan, and lignin increase with plant age, while water extractives decrease. Protein content is higher in young plants, while flavonoid content depends on the phenological stage, decreasing in the early flowering stage and then increasing as plants enter early senescence. Our results can aid in finding the optimal harvesting stage of S. europaea, depending on the component of interest.

The stone of Cornus mas L. remains the least known morphological part of this plant, whereas the fruit is appreciated for both consumption purposes and biological activity. The stone is considered to be a byproduct of fruit processing and very little is known about its phytochemical composition and biological properties. In this study, the complete qualitative determination of hydrolyzable tannins, their quantitative analysis, total polyphenolic content, and antioxidant properties of the stone of C. mas are presented for the first time. The 37 identified compounds included the following: various gallotannins ( 11 ), monomeric ellagitannins ( 7 ), dimeric ellagitannins ( 10 ), and trimeric ellagitannins ( 7 ). The presence of free gallic acid and ellagic acid was also reported. Our results demonstrate that C. mas stone is a source of various bioactive hydrolyzable tannins and shows high antioxidant activity which could allow potential utilization of this raw material for recovery of valuable pharmaceutical or nutraceutical substances. The principal novelty of our findings is that hydrolyzable tannins, unlike other polyphenols, have been earlier omitted in the evaluation of the biological activities of C. mas . Additionally, the potential recovery of these bioactive chemicals from the byproduct is in line with the ideas of green chemistry and sustainable production.

In this study Salicornia sinus-persica, a succulent halophyte was assessed for its potential to be used as a feedstock for bioethanol production. For such succulent, salty, green biomasses, direct fractionation and fermentation allow for water preservation in the process. Fresh biomass of S. sinus-persica was collected and split into two fractions by wet fractionation; liquid (juice) and solid (pulp). Sugar contents were found to be 1.0-1.5% for the juice fraction and 50% (w/w) for the fresh pulp. Direct fermentation of the juice using Saccharomyces cerevisiae showed no salt inhibition of the yeast and ethanol yields of ~70% were achieved. A pretreatment study was carried out for the pulp fraction applying mild hydrothermal pretreatment. Cellulose convertibility was found to be significantly higher for severity factors above 2.00, and the highest ethanol yield (76.91 ± 3.03%) was found at process severity of 3.06 (170 °C, 10 min).

The large water consumption (1.9-5.9 m(3) water per m(3) of biofuel) required by biomass processing plants has become an emerging concern, which is particularly critical in arid/semiarid regions. Seawater, as a widely available water source, could be an interesting option. This work was to study the technical feasibility of using seawater to replace freshwater in the pretreatment of date palm leaflets, a lignocellulosic biomass from arid regions, for bioethanol production. It was shown that leaflets pretreated with seawater exhibited lower cellulose crystallinity than those pretreated with freshwater. Pretreatment with seawater produced comparably digestible and fermentable solids to those obtained with freshwater. Moreover, no significant difference of inhibition to Saccharomyces cerevisiae was observed between liquids from pretreatment with seawater and freshwater. The results showed that seawater could be a promising alternative to freshwater for lignocellulose biorefineries in coastal and/or arid/semiarid areas., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Date palm residues are one of the most promising lignocellulosic biomass for bioethanol production in the Middle East. In this study, leaflets and rachis were subjected to hydrothermal pretreatment to overcome the recalcitrance of the biomass for enzymatic conversion. Evident morphological, structural, and chemical changes were observed by scanning electron microscopy, X-ray diffraction, and infrared spectroscopy after pretreatment. High glucan (>90% for both leaflets and rachis) and xylan (>75% for leaflets and >79% for rachis) recovery were achieved. Under the optimal condition of hydrothermal pretreatment (210°C/10 min) highly digestible (glucan convertibility, 100% to leaflets, 78% to rachis) and fermentable (ethanol yield, 96% to leaflets, 80% to rachis) solid fractions were obtained. Fermentability test of the liquid fractions proved that no considerable inhibitors to Saccharomyces cerevisiae were produced in hydrothermal pretreatment. Given the high sugar recovery, enzymatic digestibility, and ethanol yield, production of bioethanol by hydrothermal pretreatment could be a promising way of valorization of date palm residues in this region.

Salicornia bigelovii straw was characterized and evaluated as a potential lignocellulosic bioethanol feedstock. S. bigelovii used in the study was grown in the United Arab Emirates using saltwater (40ppt) for irrigation. Salt removal was performed prior to pretreatment to protect the processing equipment and avoid inhibition of enzymes and yeast. Composition of the washed biomass was comparable to traditional lignocellulosic biomasses with relatively high glucan and xylan content (26 and 22g/100gDM, respectively) but with lower lignin content (7g/100gDM). The washed feedstock was subjected to hydrothermal pretreatment, producing highly digestible (up to 92% glucan-to-glucose conversion) and fermentable (up to 100% glucose-to-ethanol conversion) fiber fractions. Liquid fractions obtained in the pretreatment did not show inhibition towards Saccharomyces cerevisiae. No significant differences among the enzymatic convertibility and microbial fermentability of the fibers as well as low xylose recoveries suggest that lower severity pretreatment conditions could be exploited for S. bigelovii., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Prairie cordgrass (PCG) was pretreated by sequential extrusion and clean fractionation (CF) processing. Following CF, PCG was fractionated into cellulose, hemicellulose and lignin-rich fractions. Cellulose pulp was then enzymatically hydrolyzed, producing glucose. The main purpose of this study was to produce the highest glucose yield as possible. The effects of time, temperature, catalyst concentration and solvent mixture composition on the fractionation were tested. Different proportions of methyl isobutyl ketone (MIBK), ethanol and water with sulfuric acid as a catalyst were evaluated. Optimal conditions for sequential extrusion and clean fractionation (39 min, 129 °C, 0.69% catalyst, and 28% MIBK) resulted in higher glucose yield (92%), and more lignin (87%) and xylan (95%) removal than for clean fractionation alone. Pairwise comparison of raw PCG with extruded PCG clean fractionation revealed no difference in glucose yields, but xylan and AIL removal were higher in the case of clean fractionation of the pre-extruded PCG., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The purpose of this study was to fractionate switchgrass (SG) to obtain hemicellulose-, lignin-rich fractions and highly digestible pulp, using a clean fractionation (CF) approach. The main objective was to produce highest glucose yield in the enzymatic hydrolysis of pulp. Effects of processing factors such as time (10-50 min), temperature (120-160 °C), catalyst concentration (0.21-0.93% w/w sulfuric acid) and organic solvent mixture composition (7-43% w/w methyl isobutyl ketone) were evaluated. Response surface methodology and central composite design were used for process optimization and statistical analyses. High lignin (75-93%) and xylan (83-100%) removal from biomass were obtained, leaving solid pulp rich in glucan (78-94%). High enzymatic hydrolysis glucose yields (more than 90%) were obtained for selected optimal conditions. Pulp can be used for ethanol production while separated xylan and lignin fractions can be used as a feedstock for value-added products which suggests the applicability of clean fractionation technology in a biorefinery concept., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Switchgrass was used as a lignocellulosic feedstock for second generation ethanol production, after pretreatment using sulfuric acid-catalyzed modified clean fractionation based on NREL's (National Renewable Energy Laboratory) original procedure. Optimization of temperature, catalyst concentration and solvent composition was performed using Response Surface Methodology, and 59.03 ± 7.01% lignin recovery, 84.85 ± 1.34% glucose, and 44.11 ± 3.44% aqueous fraction xylose yields were obtained at 140.00 °C, 0.46% w/w catalyst concentration, 36.71% w/w ethyl acetate concentration, and 25.00% w/w ethanol concentration. The cellulose fraction did not inhibit the fermentation performance of Saccharomyces cerevisiae and resulted in an ethanol yield of 89.60 ± 2.1%., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Lignin extracted from prairie cordgrass, switchgrass, and corn stover (using ethyl acetate-ethanol-water organosolv pretreatment) was analyzed and characterized using several methods. These methods included analysis of purity (by determination of Klason lignin, carbohydrate, and ash contents), solubility (with several organic solvents), phenolic group analysis (ultraviolet ionization difference spectra, and nitrobenzene oxidation), and general functional group analysis (by (1)H NMR). Results showed that all the examined lignin samples were relatively pure (contained over 50% Klason lignin, less than 5% carbohydrate contamination, and less than 3% ash), but switchgrass-derived lignin was observed to be the purest. All the lignins were found to contain high amounts of phenolic groups, while switchgrass-derived lignin was the most phenolic, according to the ionization difference spectra. Nitrobenzene oxidation revealed that all the lignin samples contained available guaiacyl units in high amounts., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The main objective of this study was to fractionate prairie cordgrass (PCG) obtaining the highest cellulose digestibility. Following clean fractionation (CF) processing, the PCG lignocellulosic biomass was fractionated into three main building blocks: cellulose, hemicellulose and lignin. Effects of processing factors such as time, temperature, catalyst concentration and organic solvent mixture composition were evaluated. Organic solvent-aqueous mixture contained methyl isobutyl ketone (MIBK), ethanol and water in different proportions. Sulfuric acid was used as a catalyst. In order to evaluate the degree of pre-treatment, enzymatic saccharification was employed on the cellulose fraction obtained from the CF process. Response surface methodology was used for process optimization and statistical analysis. Optimal conditions (39 min, 154°C, 0.69% catalyst and 9% MIBK) resulted in 84% glucose yield and 87% acid insoluble lignin (AIL)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The World Health Organization (WHO) conference on a "second wave" epidemic of cardiovascular diseases connected with arterial sclerosis (AS) foresee that in 2020 cardiovascular diseases will most likely be the leading cause of death in the world. The development of AS begins in youth and progresses with age. It's intensity depends on the risk factors involved, such as: smoking, hypertension, obesity and fat and sugar disorder in a body. Many of these risk factors, manifesting themselves as diseases in adults, can be found during adolescence. The aim of this study was to establish the spread of smoking and other risk factors of cardiovascular diseases, like: hereditary and increasing incidence hypertension and body mass index (BMI), among youth of upper gymnasium school in Podkarpacie. The research was conducted between November 2007 and March 2008, using 193 volunteer students from upper and lower gymnasium schools, aged between 16-20 years. Our research methods included: diagnostic questionnaire, measurement of blood pressure (BP) through the use of sphygmomanometer, as well as anthropometric measurements including high, weight and body mass estimation. BP was established by obtaining an average between two measurements taken under normal conditions. The results were statistically analyzed, in with the in dependent test chi-Parson square, the level of changes a = 0.05--was used. The research showed that 23.31% of respondents smoke, that's 64.44% girls, and 35.56% boys. 12.41% of the girls and 15.09% of boys smoke on regular basis. And 8.57% girls and 15.09% boys smoke from time to time. More than half of young smokers (51.10%) smoked for longer than 2 years, and the initiations of smoking starts at the age of 15 (26.67%) and the age of 16 (26.67%). 10 and more cigarettes a day smoke 26.67% of boys and 13.79% girls. 75.74% of respondents agree that they are victims of passive smoking. Through 17.61% of respondents (mostly boys 64.70%) we found increasing incidence of hypertension, and 82.35% were related to systolic BP. In the group of people with higher BP systolic hypertension demonstrated itself in 35.72% of positive cases, while diastolic hypertension related to 16.66% of the population and was present mainly among adolescence girls. Most of respondents with higher systolic (75.00%) and diastolic (83.00%) BP were found to be present in those with an obesity problem (50.00%, 10.00%) than in those with correct BMI (12.91%, 5.81%).Hereditary risk factors of AS, from father side, was found among 33.67% of respondents, and mother side, through 23.31% of respondents. Through respondents parents we found quite often: hypertension (fathers 18.65%, mothers 10.36%) and overweight and obesity (fathers 15.03%, mothers 13.99%) also through fathers we found hiperlipidemia (14.51%). Through mothers only, we found cases of diabetes (2.07%) but we didn't find heart stroke cases, which were found through fathers only (2.07%). Among respondents, 43.52% cases, we found one of risk factor of AS and more than half of respondents (56.48%) we found co -existence of 2 and more factors, including: 30.57%--2, 19.18%--3, 5.70%--4, 1.03%--5 risk factors. Through all respondents we found the existence of at least one of the risk factor of AS and through more than half of them, co-existence of two and more risk factors. Hereditary (33.67%--father side, 23.31%--mother side) and smoking (23.31%) were the common risk factors of AS in youth. An increase of hypertension and an increase incidence of BMI were present in (17.61%, 12.43%) respondents.

The aim of our study was to check the responsiveness the chemoreceptor reflex in 28 young mildly hypertensive men (HTS), aged 18-32 years and 25 normotensive male subjects (NTS) aged 19-32 years, before and after 3-months dynamic exercise training. We tested the hypothesis that dynamic training reduces arterial chemoreceptor drive in mild hypertension. Circulatory response to 3-min hyperoxic inactivation of arterial chemoreceptors induced by 70% oxygen breathing was measured before and after training. Arterial blood pressure (BP) was recorded continuously by Finapres method, stroke volume and arm blood flow were registered by impedance reography, heart rate by ECG. Both groups were submitted to moderate 3-months dynamic exercise training. Before training the hyperoxic breathing caused in HTS a significant decrease in systolic BP by 6+/-1 mmHg p<0.01, in diastolic BP by 2+/-0.6 mmHg p<0.01, and in total peripheral vascular resistance (TPR) by 0.24+/-0.04 TPRU (p<0.01). After training hyperoxia augmented systolic BP by 2.64+/-1.9 mmHg (NS), diastolic BP by 2+/-1 mmHg p<0.05, and TPR by 0.043+/-0.05 TPRU (ANOVA). In NTS before training brief hyperoxia produced insignificant change in BP and TPR. In NTS after training hyperoxia increased systolic BP by 4.2 mm Hg+/-1.23 p<0.01 and diastolic BP by 3.1+/-0.6 mmHg p<0.01 respectively and TPR by 0.053+/-0.02 TPRU. Our results confirm earlier finding on the enhanced arterial chemoreceptor reflex drive in mild human hypertension. We conclude that normalizing arterial blood pressure in subjects with mild hypertension which occurred after 3-months dynamical exercise training is due to attenuation of the sympathoexcitatory chemoreceptor reflex drive by exercise training. The mechanism of this effect requires further study.

The role of polyunsaturated n-3 fatty acids in prevention of many diseases, especially cardiovascular diseases, is becoming more and more important. In the article most important, selected by the author, studies on their legitimacy of application in prevention of coronary heart disease, sudden death and general cardio-protection are presented.

The objective of our study was to compare the cardiovascular effects of moderate exercise training in healthy young (NTS, n=18, 22.9+/-0.44 years) and in hypertensive human subjects (HTS, n=30, 23+/-1.1). The VO(2max) did not significantly differ between groups. HTS of systolic blood pressure (SBP) 148+/-3.6 mmHg and diastolic blood pressure(DBP) 88+/-2.2 mmHg, and NTS of SBP: 128.8 +/- 4 mmHg and DBP: 72 +/- 2.9 mmHg were submitted to moderate dynamic exercise training, at about 50% VO(2max) 3 times per week for one hour, over 3 months. VO(2max) was measured by Astrand's test. Arterial blood pressure was measured with Finapres technique, the stroke volume, cardiac output and arm blood flow were assessed by impedance reography. Variability of SBP and pulse interval values (PI) were estimated by computing the variance and power spectra according to FFT algorithm. After training period significant improvements in VO(2max) were observed in NTS- by 1.92 +/-0.76 and in HTS by 3+/-0.68 ml/kg/min). In HTS significantly decreased: SBP by 19 +/-2.9 mmHg, in DBP by 10.7+/-2 mmHg total peripheral resistance (TPR) by 0.28 +/-0.05 TPR units. The pretraining value of low frequency component power spectra SBP (LF(SPB)) was significantly greater in HTS, compared to NTS. PI variance was lower in HTS, compared to NTS. After physical training, in HTS PI variance increased suggesting a decrease in frequency modulated sympathetic activity and increase in vagal modulation of heart rate in mild hypertension. A major finding of the study is the significant decrease of resting low frequency component SBP power spectrum after training in HTS. The value of LF(SPB) in trained hypertensive subjects normalized to the resting level of LF(SPB) in NTS. Our findings suggest that antihypertensive hemodynamic effects of moderate dynamic physical training are associated with readjustment of the autonomic cardiovascular control system.

Background: Primary aldosteronism (PA) is a secondary form of hypertension resulting from the autonomous hypersecretion of aldosterone. The recognition of PA has an important impact on clinical management, since the choice of therapy is different - surgical for adenoma and medical for hyperplasia., Aim: To evaluate patients with PA in regard to clinical and biochemical factors differentiating between adenoma of adrenal cortex (APA) and idiopathic adrenal hyperplasia (IHA)., Methods: We retrospectively analysed 62 patients with PA (33 females, 29 males, mean age 49.3+/-12.5 years, range 26-78) diagnosed in the Department of Hypertension between 1990-2001. In 37 patients (mean age 47.4+/-12.1 years, 22 females, 15 males) APA was diagnosed whereas in the remaining 26 patients (mean age 52.2+/-12.6 years, 14 males, 11 females) IHA was detected. Clinical manifestation, biochemical, serum aldosterone (SA), plasma renin activity (PRA) as well as echocardiographic parameters and blood pressure (BP) levels were evaluated. Diagnostic accuracy of computed tomography (CT) and scintigraphy was also assessed., Results: Mean systolic BP was significantly higher in the patients with APA. Both groups had similar mean diastolic BP. Severe hypertension, resistant to three or more medications, was found in 63.3% of all patients. Muscle weakness was reported by 39.7% of patients, polyuria - by 19%, and polydypsia - by 10.3% of patients. Patients with muscle weakness had higher mean systolic BP level and lower plasma potassium level than patients without this complaint. Symptoms suggesting cardiac arrhythmia were reported by 45% of patients. A normal potassium level was found in 25.8% of all patients. The hypokalemic patients were younger, had shorter known duration of hypertension, higher mean systolic BP level and higher SA concentration than the normokalemic patients. Supine SA levels were significantly higher in the APA group than in the IHA group (50.3+/-29.0 ng% vs 30.5+/-14.7 ng%; p<0.001). The SA/PRA ratio higher than 30:1 was found in all patients. Response to postural test with a rise in SA concentration higher than 30% was observed in 40% patients with APA and in 87.5% patients with IHA (p<0.0001). There was a strong correlation between supine and upright SA level, and systolic and diastolic BP level as well as plasma potassium level. Left ventricular hypertrophy was present in 60% of patients. The differentiation between APA and IHA was possible using CT, scintigraphy or both methods in 75%, 89.2% and 100% of patients, respectively., Conclusions: One quarter of patients with PA were normokalemic. PA should be suspected especially in patients with severe hypertension, resistant to three or more antihypertensive drugs. Changes in SA concentration during the postural tests such as CT and scintigraphy are useful for differentiation between APA and IHA.

Unlabelled: Takaysu's arteritis (TA) is regarded to be a frequent cause of hypertension in Asian population. However some reports have recently informed about increasing frequency of its also in non Asian people. The aim of this study was to evaluated own experiences on diagnosis and treatment of TA as well as prevalence of TA in hypertensive patients in Caucasian population., Materials and Methods: During last 15 years we examined 4190 hypertensive patients hospitalized in our department. Renovascular hypertension was recognized in 139 cases. The diagnosis of TA was based on angiographically proven vascular changes and its inflammatory phase on estimation increased (> 40 mm/h) sedimentation rate and immunoglobulins above normal level. The patients with acute phase of TA initially received typical immunosuppressive therapy (prednisone in monotherapy or combined with azatioprine or cyclophosphamide), followed by chronic administration of prednisone. In every case, if it was possible, we proposed angio-corrective procedure. All patients have received hypotensive and antiplatelet therapy., Results: TA was recognized in 15 patients--4 men and 11 women, average age 36.3 +/- 9.8 y. The patients with TA represented 0.37% hypertensive and 10.9% cases of renovascular hypertension. Significant stenosis of renal artery and various degree of lesions in aorta and some arteries was discovered in all persons. In the observed group hypertension was effectively controlled with 2-3 hypotensive drugs, including ACE inhibitors, diuretics and Ca antagonists. The acute phase of TA was diagnosed in 11 patients and it was treated successfully (except one case) with immunosuppressive therapy. After discontinuation of the treatment (4 patients) progression of the disease was observed. In 6 patients, characterised by clinical and biochemical remission of acute phase percutaneous angioplasty renal artery was performed. A good result in long-term follow-up period was observed in 4 cases (in 2 after repeated procedure). Surgical procedure was performed in 4 cases--in 2 on carotid and in 1 on renal and the next one on coronary artery. In first 3 cases the procedures were unsuccessful (reocclusion ?)., Conclusions: Our observation suggested that 1. The incidence of TA in hypertensive (especially renovascular hypertension) population is more frequent than expected. 2. Acute phase of the disease is indication to long-term the immunosuppressive therapy. 3. Angiocorrective procedure is necessary reflected in every case in period of remission of acute phase.

Unlabelled: The aim of the study was to analyse plasma renin activity (PRA), aldosterone (Ald) and catecholamines at rest, after psychological stress and physical exercise in patients with essential hypertension (EH) and normotensive persons with (FH +) and without (FH-) family history of hypertension., Materials and Methods: 100 men, aged 18-35 years, were investigated: 36 in EH, 32 in FH + and 32 in FH- groups. PRA, Ald and plasma level of adrenaline (A), noradrenaline (NA) and dopamine (D) were estimated at rest, after 30' of stress (Kraepelins test) and at the end and 30, after submaximal ergometric exercise., Results: The groups did not differ in respect to PRA and Ald in all periods of study as well as to A and NA at rest and during stress. A in EH and FH + as well as NA in FH + were significantly higher than FH- at the end and 30 after exercise. D in EH was higher (p < 0.05) than in both normotensive groups and at rest and stress than FH- during exercise and recovery. There were also some correlations between PRA, Ald and catecholamines. In FH + and FH- but not in EH group PRA and Ald positively correlated at rest (r = 0.588 and 0.612) and during stress (r = 0.626 and 0.477). On the contrary in EH as well as FH + groups PRA positively correlated with A (r = 0.385 and 0.368) and NA (r = 0.370 and 0.386) at rest. In addition PRA correlated positively with A during stress (r = 0.368) as well as with NA during recovery (r = 0.313) in FH + groups. Ald correlated with D positively in FH + (r + 0.380) and negatively (r = 0.304) in FH- at rest, whereas Ald was positively correlated with A in EH (r = 0.511) as well as in FH + (r = 0.354) during exercise., Conclusions: Hypertension and family history of it changes adrenergic reactivity and influences the relationship between plasma renin activity, aldosterone, and catecholamines.

Unlabelled: Nonspecific aortoarteritis (Takayasu's arteritis) is a systemic disease of unknown cause. No characteristic symptoms may delay diagnosis and treatment as well as deteriorate prognosis. The aim of the study was analysis of prevalence, course, diagnosis and treatment of Takayasu's arteritis. 10 patients (9 female, 1 male) with inflammatory phase of Takayasu's arteritis were seen at the Department of Hypertension of Institute of Cardiology between 1981 and 1992 (0.1% of all patients). The diagnosis was performed on the basis of typical arteriographic picture and laboratory investigations such as elevated of erythrocyte sedimentation rate and increase of immunoglobins, especially G fraction levels. Three patients were in poor general condition (fever, tachypnea, progressive weakness and severe arthralgia); in the remaining the symptoms were less severe, consisting mainly of weakness and arthralgia. All patients had multiple sites of arterial involvement (clinically and angiographically). Hypertension occurred in 9, aortic valve disease in 4, mitral valve disease in 2 and angina pectoris in 3 persons. All patients were treated with prednisone in initial dose of 1-1.5 mg/kg daily. After normalization of inflammatory indices (in average after 3 weeks therapy) this dose was gradually diminished to maintenance dose 5-15 mg daily. 4 patients were treated with prednisone in monotherapy, 6 received combined therapy--prednisone and cyclophosphamide or prednisone and azathioprine. Responses to immunosuppressive treatment were usually very good. In follow-up period (43.4 +/- 30.7 months) in 9 patients the regression of symptoms of inflammatory phase was observed (all patients were treated with maintenance dose of prednisone). Immunosuppressive therapy was ineffective in one woman, despite long term treatment with prednisone combined alternately with cyclophosphamide, azathioprine or methotrexate. She died of progressive heart and renal failure., Conclusions: 1. Takayasu's arteritis is serious systemic disease with considerable risk of death. 2. Early and proper management of Takayasu's arteritis can improve prognosis of this disease. 3. In every case with multiple sites of arterial involvement, especially with associated symptoms of unidentified inflammatory disease it is necessary to consider diagnosis of Takayasu's arteritis, which prevalence seems to be underestimated.

Renovascular hypertension is one of the most common causes of secondary hypertension. Its early diagnosis is particularly important, firstly because it is one of the few potentially reversible causes of chronic renal failure. In many centers, including our own, renal angioplasty (PTA) or surgery is the treatment of choice for patients with renovascular hypertension. The aim of the study was the evaluation of the early and late results of PTA versus renovascular surgery. The diagnostic procedures and clinical course of renovascular hypertension were also analyzed. Among patients with renovascular hypertension treated in our Department during the 1981-1993 years, 89 patients (46 men, 43 women) were diagnosed and having renovascular hypertension (3% of all hypertensive patients). The average duration of hypertension in this group was 5 years. High incidence of accelerated hypertension (18%) and cardiovascular complications were observed: myocardial infarction in 20.2% of cases and stroke in 4.5%. The presence of renal failure was found in 22.5% of cases, hypokalemia in 11.2%, 38.3% of patients had changes in other arteries. Renal angioscintigraphy and captopril renal scintigraphy were performed in accordance with renal arteriography in 80% of patients. Arteriography showed unilateral renal artery stenosis in 78.7% of patients and bilateral - in 21.3%. The most common cause of renovascular hypertension in our material was atherosclerosis (65.2%). Fibromuscular dysplasia and Takayasu arteritis were diagnosed less frequently (25.8% and 9.0% respectively). Forty four patients were treated with PTA, 15 underwent surgical revascularization and 11 - unilateral nephrectomy. Early beneficial therapeutic effect (normalization or improvement of blood pressure control) was observed in 88.6% for PTA and 66.7% for surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of the study was to investigate the effect of a new selective alpha 1-adrenoreceptor blocker doxazosin on blood pressure, serum lipids and lipoproteins in patients with essential hypertension. The study was done in 32 out-patients with mild-to-moderate hypertension (22 men and 10 women, mean age 45.6 +/- 10.1). After 2-week placebo period the patients were given doxazosin in increasing doses from 1 to 8 mg daily for 6 to 14 weeks (mean daily dose 2.24 +/- 1.6 mg). Twenty-nine patients completed the study. The active treatment caused highly significant drop in systolic and diastolic blood pressure both in supine and standing positions. No orthostatic hypertension was noted. There was also a statistically significant decrease in serum total cholesterol, VLDL-cholesterol, and triglyceride levels and increase in the positive prognostic lipid indicators. HDL3-cholesterol and apolipoprotein AI levels as well as HDL/total cholesterol ratio. Accordingly, the statistically significant decrease of the so called atherogenic index was noted. The drug was well tolerated and only one patient dropped from the study because of side effects. The authors conclude that doxazosin appears to be an effective and well tolerated antihypertensive drug with a favorable effect on lipid metabolism. It may be particularly useful in hypertensive patients with coexisting lipid abnormalities.

Fourteen male patients with mild hypertension, aged between 20 and 46 years (mean = 32.4 years) measured their arterial blood pressure thrice daily for 6 weeks. Prior to and after this period psychological tests were carried out, including Gough's ACL test and Spielberger's STAI questionnaire. All patients underwent also Kraeplin's test under stress conditions twice during the experiment. It was found that there is significant correlation of personality response syndromes such as: need for acceptance, inferiority complex, need for success, trust to themselves, anger and some values of blood pressure. So-called personality syndrome related to hypertension was established. Psychophysiological picture accompanying emotional stress was discussed and relationship between blood pressure values (prior to and after emotional stress) and personality syndromes were defined.

The aim of the study was to assess the usefulness of 24-hour blood pressure (BP) and heart rate (HR) monitoring in patients with "resistant" hypertension. 30 patients (44.1 +/- 9.9 years) with diastolic BP 100 mm Hg or more in spite of treatment with three or more antihypertensive drugs were studied. Ambulatory recording of BP and HR was performed by means of Del Mar Avionics monitoring system 9000. Mean recording time was 21.5 hours and mean number of measurements during one recording--56.7. Mean ambulatory systolic and diastolic BP values were significantly lower than mean value of three casual measurements (146.0 +/- 24.6 vs 171.5 +/- 21.2 mm Hg for systolic and 97.2 +/- 11.3 vs 110.4 +/- 7.5 mm Hg for diastolic BP p less than 0.01) In 14 (46.6%) systolic BP and in 10 patients (33.3%) diastolic BP were normal. The patients with normal and abnormal ambulatory BP recordings did not differ in regard to age and mean clinic BP levels. However, patients with abnormal ambulatory BP recordings were more often overweight and showed a greater frequency of left ventricular hypertrophy and family history of hypertension and its complications. The results of the study show that ambulatory BP monitoring may be of value in assessing the response to antihypertensive treatment in patients with so called resistant hypertension as judged on the basis of clinic pressure.