29 research outputs found

    Extradermal melanin transfer? : lack of macroscopic spleen melanization in old C57BL/6 mice with de-synchronized hair cycle

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    In quest of alternate, extradermal path of melanin transfer from skin to the visceral organs, we suggested that some portions of such melanin may be deposited in the spleen, which in young black C57BL/6 mice is often melanized. Here, we confirm these observation using young C57BL/6 female mice (up to 17 weeks) and show that this phenomenon cannot be observed in old animals where the hair cycle is not synchronized any more. The experiments were carried out both on spontaneous and depilation-induced hair cycle. We have checked it as a side-observation over many other experiments carried out on young and old C57BL/6 female mice (up to 2.5 years of life). The presence or absence of melanin in the spleens was checked macroscopically, and histologically by Fontana-Masson (FM) staining, and synchronization of the hair cycle - by standard histomorphometric analysis of the back skin hair follicles. In about 40% of old spleens black FM-stainable 'debris' could be found under closer histological examination. This study shows that, at least in part, the phenomenon of splenic melanosis in C57BL/6 mice can be correlated with the synchronized skin melanization parallel to the hair cycle progress, and that splenic melanin undergoes gradual degradation during the mouse life

    The effect of hemodynamically-guided hypotensive therapy in one-year observation: Randomized, prospective and controlled trial (FINEPATH study)

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    Background: The use of impedance cardiography (ICG) revealed to provide beneficial blood pressure (BP) lowering effect. However, the follow-up in previous trials was short and brachial BP was the only evaluated hemodynamic variable. Thus, we aimed to estimate the influence of ICG-guided therapy on brachial and central BP, impedance-derived hemodynamic profile and echocardiographic features after 12 months in a randomized, prospective and controlled trial (NCT01996085). Methods: One hundred and forty-four hypertensives were randomly assigned to groups of empiric (GE) and ICG-guided therapy (HD). Office BP, ambulatory BP monitoring, central BP and echocardiography (left ventricular hypertrophy and diastolic function assessment) were performed before and after 12 months of treatment. Results: Blood pressure reduction was higher in HD (office BP: 21.8/14.1 vs. 19.9/11.8 mm Hg; mean 24-h BP: 19.0/10.9 vs. 14.4/9.2 mm Hg). However, the only statistically significant differences were: percentage of patients achieving BP reduction of minimum 20 mm Hg for of­fice diastolic BP (27.3% vs. 12.1%; p = 0.034) and mean 24-h systolic BP (49.1% vs. 27.3%; p = 0.013). More pronounced improvement in the left ventricular diastolic dysfunction (delta E/A 0.34 vs. 0.12, p = 0.017) was the only other beneficial hemodynamic effect. Conclusions: Beneficial BP lowering effect of hemodynamically-guided pharmacotherapy, observed previously in short-term observation, persists over time. Hemodynamic effects of such a treatment approach, especially those of prognostic value (central BP, myocardial hypertrophy), should be evaluated in further studies including patients with resistant hypertension, heart failure, diabetes mellitus and chronic kidney disease

    Silver nanoparticles induced changes in DNA methylation and histone H3 methylation in a mouse model of breast cancer

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    The importance of epigenetic changes as a measurable endpoint in nanotoxicological studies is getting more and more appreciated. In the present work, we analyzed the epigenetic effects induced by citrate- and PEG-coated 20 nm silver nanoparticles (AgNPs) in a model consisting of 4T1 breast cancer tumors in mice. Animals were administered with AgNPs intragastrically (1 mg/kg b.w. daily—total dose 14 mg/kg b.w.) or intravenously (administration twice with 1 mg/kg b.w.—total dose 2 mg/kg b.w.). We observed a significant decrease in 5-methylcytosine (5-mC) level in tumors from mice treated with citrate-coated AgNPs regardless of the route of administration. For PEG-coated AgNPs, a significant decrease in DNA methylation was observed only after intravenous administration. Moreover, treatment of 4T1 tumor-bearing mice with AgNPs decreased histone H3 methylation in tumor tissue. This effect was the most pronounced for PEG-coated AgNPs administered intravenously. No changes in histone H3 Lys9 acetylation were observed. The decrease in methylation of DNA and histone H3 was accompanied by changes in expression of genes encoding chromatin-modifying enzymes (Setd4, Setdb1, Smyd3, Suv39h1, Suv420h1, Whsc1, Kdm1a, Kdm5b, Esco2, Hat1, Myst3, Hdac5, Dnmt1, Ube2b, and Usp22) and genes related to carcinogenesis (Akt1, Brca1, Brca2, Mlh1, Myb, Ccnd1, and Src). The significance of the observed changes and the mechanisms responsible for their development are unclear, and more research in this area is warranted. Nevertheless, the present work points to the epigenetic effects as an important level of interaction between nanomaterials and biological systems, which should always be taken into consideration during analysis of the biological activity of nanomaterials and development of nanopharmaceuticals

    Endocrine Responses to Physical Training and Tribulus Terrestris Supplememtation in Middle-Age Men

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    The aim of this study was to evaluate the effects of steroidal saponin supplementation on blood concentration of T, GH and IGF-1. The research involved 14 men between the age of 45 and 60 years. The duration of the experiment was 12 weeks. There were two series of laboratory tests. Independent tests were conducted at the beginning and after 12 weeks of the intervention. A two-way repeated measures ANOVA revealed a statistically significant effect of the intervention on the following variables: T-Ch (η2 = 0.542), HDL-Ch (η2 = 0.522), LDL-Ch (η2 = 0.587), T (η2 = 0.603), IGF-1 (η2 = 0.512) and GH (η2 = 0.621). Thus, FFM significantly increased while TBF and BM decreased in comparison to pre-intervention levels. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a successful form of counteracting the aging process. Nevertheless, the effects of TT supplementation on the concentration of T as well as GH and IGF-1, requires further studies, especially in middle-aged and older subjects, along with different exercise programs. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a major form of counteracting the aging process

    Współczesne wyzwania teorii i praktyki bezpieczeństwa

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    Z wprowadzenia: "Nauki o bezpieczeństwie mają niespełna sześcioletnią historię, kiedy to 8 sierpnia 2011 roku minister Nauki i Szkolnictwa Wyższego ustanowiła je swoim rozporządzeniem jako nawą dyscyplinę naukową w dziedzinie nauk społecznych nowo utworzonego obszaru wiedzy np. nauki społeczne. Samo zaś bezpieczeństwo należy do jednej z najbardziej elementarnych potrzeb człowieka. Jest podstawowym prawem i jego potrzebą, sprowadza się ono do eliminowania sytuacji zagrażających człowiekowi i jego dobrom. Poczucie bezpieczeństwa jest jedną z dwóch najistotniejszych potrzeb człowieka warunkującą dalszy jego rozwój i funkcjonowanie w społeczeństwie. Bezpieczeństwo ma umożliwić prawidłowy rozwój społeczny przy przestrzeganiu zasad współżycia społecznego."(...)Publikacja powstała w ramach projektu badawczego Krakowskiej Akademii im. Andrzeja Frycza Modrzewskiego nr WNoB/DS/3/2015-KO

    The Effects of a Low Calorie Ketogenic Diet on Glycaemic Control Variables in Hyperinsulinemic Overweight/Obese Females

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    Diet is a factor which can influence both glycaemic variables and body mass. The aim of this study was to compare the influence of a 12-week, well-planned, low-calorie ketogenic diet (LCKD) on hyperglycaemic, hyperinsulinemic and lipid profile in adult, overweight or obese females. Ninety-one females who participated in the study were divided into two groups: a LCKD group who followed a hypocaloric ketogenic diet (8% of carbohydrate, 72% of fat and 20% of proteins) (n = 46), and a control group (CG) (n = 45) who continued their typical diet (50% of carbohydrates, 32% of fat and 18% of proteins). Methods: Baseline and post-intervention glucose (Gl), insulin (I), glycated haemoglobin (HbA1c), Homeostatic model assessment HOMA-IR, triglycerides (TG) and high-density cholesterol (HDL-C) were evaluated. Also, body mass (BM), waist circumference (WC), hip circumference (HC) and thigh circumference (TC) were measured. Results: Compared with the CG, there were significant changes observed in the LCKD group regarding all biochemical variables. Also, BM, TC, WC and AC changed significantly in the LCKD group compared with the CG. Conclusions: The 12-week LCKD intervention changed the glucose control variables, body mass, as well as waist, hip and thigh circumferences. A low-calorie ketogenic diet may be recommended for adult females with glucose control variables disturbance and excess body mass

    Correction of Dynamical Properties of Data Acquisition Systems

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    Accurate and fast measurements are important in many areas of everyday engineering and research activities. This paper proposes a method that gives such measurements, additionally shortening the time in which they are obtained. To achieve this, a supplementary discrete-time filter, estimating values of delayed samples of the measured signal, is attached to the output of the data acquisition system. This filter is identified with the use of classical estimation methods, based on a dynamical model of the data acquisition system. The definition of the cost function minimised during filter identification depends on the nature of the environment in which measurements are acquired. The considerations presented in this paper are illustrated with four corresponding simulated case study examples. They show how, in a very simple way, dynamical properties of data acquisition systems may be corrected, and thus improved, using the corresponding supplementary discrete-time filters. The improvement, measured by the correction quality index introduced in the paper, was from a few times up to more than 100. The paper also raises the issue of obtaining models for tuning of the supplementary discrete-time filter. The considerations presented may be applied to formulate the artificial intelligence of data acquisition systems as well as sensors. Finally, the paper proposes to implement this intelligence as a knowledge base of the expert system

    Dietary Recommendations for Cyclists during Altitude Training

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    The concept of altitude or hypoxic training is a common practice in cycling. However, several strategies for training regimens have been proposed, like “live high, train high” (LH-TH), “live high, train low” (LH-TL) or “intermittent hypoxic training” (IHT). Each of them combines the effect of acclimatization and different training protocols that require specific nutrition. An appropriate nutrition strategy and adequate hydration can help athletes achieve their fitness and performance goals in this unfriendly environment. In this review, the physiological stress of altitude exposure and training will be discussed, with specific nutrition recommendations for athletes training under such conditions. However, there is little research about the nutrition demands of athletes who train at moderate altitude. Our review considers energetic demands and body mass or body composition changes due to altitude training, including respiratory and urinary water loss under these conditions. Carbohydrate intake recommendations and hydration status are discussed in detail, while iron storage and metabolism is also considered. Last, but not least the risk of increased oxidative stress under hypoxic conditions and antioxidant supplementation suggestions are presented

    A Strong Impact of Soil Tetracycline on Physiology and Biochemistry of Pea Seedlings

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    Antibiotics are a new type of contaminants found in the environment. They are increasingly used in farm animal production systems and may accumulate in crops, limiting the plant growth rate and nutritive value. The aim of this study was to determine the effects of tetracycline (TC) on physiological and biochemical properties of pea seedlings. The presence of TC in the soil during 24 hours did not result in any distinct changes of the seedlings. However, after five days (120 h) of soil TC action, the seedling appearance and metabolic activities were significantly affected. Leaves lost their green coloration as a result of a 38% degradation of their chlorophyll. Total protein was isolated from shoots of pea grown for 120 h in TC-supplemented perlite (250 mg × L−1) or perlite with no TC (control plants). The 2D electrophoretic maps of proteins from non-TC shoots contained 326 spots, whereas maps of shoot proteins from TC-treated seedlings contained only 316 spots. The identity of 26 proteins was determined. The intensity of most proteins (62%) increased. This was particularly visible with diphosphate kinase, superoxide dismutase [Cu-Zn], peroxiredoxin, and glutathione S-transferase. A distinctly increased quantity of a protein involved in photosynthesis (photosystem II stability/assembly factor HCF136) was also noted. One protein was detected only in shoots of TC-treated plants (as opposed to controls); however, it could not be identified. Moreover, at the highest concentration of TC (250 mg × L−1 of perlite), a sharp increase in free-radical content was observed along with the amount of callose deposited in vascular bundles of leaves and roots and the occurrence of masses of dead cells in roots. It was found, therefore, that tetracycline which has been known for inhibiting predominantly the attachment of aminoacyl-tRNA to the ribosomal acceptor in bacteria can disturb diverse metabolic pathways in plants

    The Effects of a Ketogenic Diet on Exercise Metabolism and Physical Performance in Off-Road Cyclists

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    The main objective of this research was to determine the effects of a long-term ketogenic diet, rich in polyunsaturated fatty acids, on aerobic performance and exercise metabolism in off-road cyclists. Additionally, the effects of this diet on body mass and body composition were evaluated, as well as those that occurred in the lipid and lipoprotein profiles due to the dietary intervention. The research material included eight male subjects, aged 28.3 ± 3.9 years, with at least five years of training experience that competed in off-road cycling. Each cyclist performed a continuous exercise protocol on a cycloergometer with varied intensity, after a mixed and ketogenic diet in a crossover design. The ketogenic diet stimulated favorable changes in body mass and body composition, as well as in the lipid and lipoprotein profiles. Important findings of the present study include a significant increase in the relative values of maximal oxygen uptake (VO2max) and oxygen uptake at lactate threshold (VO2 LT) after the ketogenic diet, which can be explained by reductions in body mass and fat mass and/or the greater oxygen uptake necessary to obtain the same energy yield as on a mixed diet, due to increased fat oxidation or by enhanced sympathetic activation. The max work load and the work load at lactate threshold were significantly higher after the mixed diet. The values of the respiratory exchange ratio (RER) were significantly lower at rest and during particular stages of the exercise protocol following the ketogenic diet. The heart rate (HR) and oxygen uptake were significantly higher at rest and during the first three stages of exercise after the ketogenic diet, while the reverse was true during the last stage of the exercise protocol conducted with maximal intensity. Creatine kinase (CK) and lactate dehydrogenase (LDH) activity were significantly lower at rest and during particular stages of the 105-min exercise protocol following the low carbohydrate ketogenic diet. The alterations in insulin and cortisol concentrations due to the dietary intervention confirm the concept that the glucostatic mechanism controls the hormonal and metabolic responses to exercise
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