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EN
Thermolysins constitute a family of secreted bacterial metalloproteases expressed, among others, by several pathogens. Strains of Staphylococcus pseudintermedius isolated from diseased dogs and judged as protease-positive, by skim milk agar plate culture, were investigated for protease content. No proteolytic activity was detected when the bacteria were grown in regular liquid media. Unexpectedly, supplementation of the medium with calcium ions resulted in expression of a metalloprotease and profound changes in the profile of extracellular proteins. On the basis of homology to other staphylococcal metalloproteases, the nucleotide sequence of the gene encoding this protease (Pst) and its flanking regions was determined. The full-length pst codes for a protein with an open reading frame of 505 amino acids. The internal region contains the HEXXH catalytic domain that is conserved in members of the thermolysin family. Regardless of the presence of calcium in the medium, the expression of the protease gene was of the same intensity. This suggests that regulation of the metalloprotease production by calcium ions is at a post-transcriptional level. Isolates of S. pseudintermedius exhibit a proteolytic phenotype due to the metalloprotease expression, however only in presence of calcium ions, which most probably stabilize the structure of the protease.
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An extensively used fluoroquinolone antibiotic ciprofloxacin shows a broad-spectrum antibacterial activity against both gram-positive and gram-negative strains. It works mainly by the inhibition of DNA gyrase and topoisomerase IV which results in impaired DNA replication leading towards microbial cell death. Eryptosis is an alternative term used for suicidal erythrocyte death. In current study, eryptotic effect of ciprofloxacin was investigated by exposing erythrocytes for 48 hours to the different concentrations (45-90µM) of ciprofloxacin. The experimental work related to the investigation of eryptosis was done by cell size measurement and confirmation of calcium role in membrane blebbing. As a possible mechanism of eryptosis, oxidative stress induced by ciprofloxacin was determined by catalase, glutathion peroxidase and superoxide dismutase activities measurement. Similarly, necrotic effect of ciprofloxacin was also illustrated by hemolysis measurement. Results of our study revealed that the therapeutical doses of ciprofloxacin may induce oxidative stress by significant decrease in superoxide dismutase, catalase and glutathione peroxidase activities as well as induce eryptosis, featured by erythrocytes membrane blebbing and hemolysis.
EN
The effect of calcium compounds present in lignite on the effectiveness of steam gasification of lignite chars has been studied at the temperature of 750° C. lignites from three Polish mines were used. Samples were demineralized with 2M HCl to remove alkali and alkaline earth metals. The demineralized lignites were loaded with Ca using: calcium acetate Ca(CH3COO)2, calcium hydroxite Ca(OH)2 and calcium carbonate CaCO3. The lignite samples were carbonized at the temperature of 900 °C in order to obtain lignite chars. The gasification process, applying steam as the oxidizing agent, was studied using thermogravimetric analysis at the temperature of 750 °C. For the process of gasification, the catalytic effect caused by the presence of calcium in lignite was found to be very important (2-7 times reaction rate acceleration). Even more important appeared to be the fact, that the effect of calcium was practically independent of the kind of calcium compound used. The inherent minerals present in raw lignite exert a similar catalytic effect to that caused by the added calcium.
PL
Przedstawiono metodę bilansowania wapnia w kotle fluidalnym. Zaprezentowano metodykę wyznaczania skuteczności odsiarczania, stosunku molowego Ca/S, stopnia wykorzystania sorbentu, a także metody wyznaczania właściwości sorpcyjnych sorbentów przeznaczonych do kotłów fluidalnych, a mianowicie wskaźników reaktywności i sorpcji bezwzględnej. Przedstawiono także propozycje metodyki wyznaczania części palnych oraz węglanów w popiele.
EN
The method of the elaboration of calcium balance in fluidized bed boilers is presented. Also the effectiveness of desulfurization, Ca/S ratio, rate of sorbent molaire consumption and the method of determination of sorption properties of sorbents used in fluidized bed boilers. The method of determination of share of combustible and carbonates in the ash is proposed.
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Background. Long-term exercise contributes to the inhibition of osteoblast cell activity and to the decrease of bone resorption. Objectives. The research objective was to analyze the chronic effect of regular, long-term physical activity and physical inactivity on carboxyterminal collagen cross-linking telopeptide levels (CTx) and calcium levels in healthy adults. Material and methods. This study was a prospective cohort study. Fifty-four men and women, aged 17–26 years, were divided into 2 groups of 27 people each: exercise and non-exercise. This research was carried out from April 2015 to April 2016 at the Faculty of Medicine, Syiah Kuala University, Aceh, Indonesia. Bone resorption can be determined by measuring the carboxyterminal cross-linking telopeptide of collagen (CTx). The data were analyzed using Student’s t-test and regression correlation analysis with a significance level of 5%. Results. The highest levels of CTx were found in the non-exercise group; the lowest levels of CTx were in the exercise group (1.6 ng/mL and 0.30 ng/mL, respectively). This difference in CTx levels between groups was statistically significant (0.52 ± 0.22 ng/mL vs 0.72 ± 0.28 ng/mL; p = 0.005). Calcium was significantly higher in the exercise group than in the non-exercise one (9.67 ± 0.30 vs 9.01 ± 0.21 mg/dl; p = 0.006). There was a negative correlation between calcium levels and CTx in the exercise group (r = 0.038; p = 0.001). Conclusions. Regular exercise led to lower CTx levels and increased calcium levels. The increase in calcium is an effect of the decrease in CTx in healthy adults. Regular exercise decreases bone resorption and increases bone calcium
EN
Mitochondrial NADP-specific isocitrate dehydrogenase (ICDH) partially purified from rabbit adrenals is sensitive to low concentrations of Ca2+. In the absence of Ca2+ (addition of 1 mM EGTA) the Km of ICDH for DL-isocitrate was 143 jaM, and in the presence of about 10 jaM Ca2+ (EGTA-Ca2+ buffer) it was decreased to 55 ¿iM. The JCm value of ICDH for NADP was similar in the absence (4.4 jxM) and in the presence (5.0 jiM) of Ca2+. The Km of mitochondrial NADP-ICDH for DL-isocitrate was higher than that of cytoplasmic NADP-ICDH from the same source.
EN
A crucial technological task that must be solved in the production of sausage products is to stabilize the product’s red colour. In this paper, we propose a scheme to determine the most significant parameters of the quality of dry-cured sausages by their colour characteristics. For this purpose, colour digital images were obtained, which were further processed using two classical colour representation systems: RGB and xyY. We monitored changes in pH and the ratio of water to dry matter in meat products. These crucial sausage properties were changed by introducing chitin-containing supplements into their recipes, which allowed us to solve two tasks simultaneously. The first comprises, as already mentioned, changing the properties of sausages to obtain correlations with colour characteristics. The second is to enrich meat products with chitin complex for preventive purposes to improve people’s nutrition. The construction of correlation dependencies using each coordinate separately in two colour systems showed that each system (RGB and xyY) has one colour channel with a maximum correlation coefficient. This is due to the colour features of sausages, which can be represented to the greatest extent with the help of only one colour coordinate in the considered colour representation systems (RGB and xyY). Using these colour coordinates will allow one to achieve maximum measurement accuracy. Thus, two tasks are being solved: the enrichment of food with dietary supplement and the development of a method to control their content.
EN
Effects of solution treatment on room temperature mechanical properties were studied in cast AZ91 (Mg-9%Al-1%Zn-0.2%Mn) and AZ91-0.5%Ca alloys. In as-cast state, the Ca addition contributed to the suppression of discontinuous β phase precipitation and the formation of Al2 Ca phase. After solution treatment, the AZ91 alloy had only a small amount of Al8 Mn5 particles, while β and Al2 Ca phases were still present in the Ca-containing alloy. In as-cast state, the AZ91-0.5%Ca alloy showed better yield strength and hardness than the AZ91 alloy. The solution treatment increased the elongation in both alloys, which eventually led to the increase in ultimate tensile strength. The solution treatment resulted in a marked decrease in yield strength and hardness in the AZ91 alloy, whereas the decrements in those values were relatively negligible in the Ca-containing alloy due to the residual phases and solution hardening effect of Ca.
EN
Background: Nutrition influence on cystic fibrosis (CF) patients survival is well documented and dietary therapy is one of basic elements of their treatment. Prolonged survival of CF patients might yet emerge comorbidities, which include bone mineral disease. The aim: The assessment of the dietary pattern and its relationship between bone density in boys and girls with cystic fibrosis. Material and methods: 89 patients aged 10-18 years from 3 Polish CF Centres were included into the study. To obtain a knowledge about quality of diet, a 3-day food record was assessed and percent of recommended for CF patients intake of energy, protein, carbohydrates, fat, vitamin D3, calcium, phosphorus was counted. Bone mineral density (BMD) in lumbar spine (L1-L4) was measured and expressed as a Z-score. To assess nutritional status, anthropometric measurements was evaluated (body weight, height and BMI). Descriptive methods, Mann-Whitney test, T-Student test, Spearman correlation and one-way ANOVA were used for statistical analyses. Results: The patients with cystic fibrosis did not meet specific for CF nutritional guidelines. A deficiency in recommended intake was observed in energy (88%), protein (82%), calcium (78%) and vitamin D3 (71%). The intake of phosphorus was higher than recommended (142%). A nutritional status was significantly reduced, as compared with the reference group (p<0.001). Boys characterized significantly lower body weight (p=0.019) and height (p=0.036) than girls as well as worse caloric (p=0.023) and carbohydrates intake (p=0.005). However, girls had reduced vitamin D3 content in their diet (p<0.001). The bone mineral density in the whole group was reduced and Z-score amounted to -0.95±1.17. Tendency to decreasing of BMD with age was observed. BMI showed important correlation with bone mineral density both in girls (p<0.001) and in boys (p=0.020). Conclusion: CF patients do not follow specific for them dietary recommendations and essential differences were observed between girls and boys. Nutritional status (BMI) showed correlation with bone mineral density in CF patients. Therefore intensive nutritional therapy according to recommendations is needed.
PL
Wprowadzenie: Wpływ żywienia na długość życia chorych z mukowiscydozą (ang. Cystic Fibrosis − CF) jest dobrze udokumentowany, a postępowanie dietetyczne jest jednym z podstawowych elementów leczenia pacjentów z CF. Systematyczne wydłużanie się wieku przeżycia chorych może powodować ujawienie się niedoborów żywieniowych prowadzących do chorób towarzyszących, jakimi są m.in. zaburzenia w gospodarce mineralnej kości. Cel: Celem pracy była ocena sposobu żywienia dziewcząt i chłopców z mukowiscydozą i jego związku z gęstością mineralną kości. Materiał imetody: Do badania włączono 89 pacjentów wwieku 10-18 lat. Wcelu ustalenia jakości diety, oceniono sposób żywienia za pomocą zapisu 3-dniowych jadłospisów, obliczając procent realizacji zapotrzebowania zgodnie z rekomendacjami opracowanymi dla pacjentów z mukowiscydozą. Dotyczyło to pokrycia zapotrzebowania kalorycznego, białka, tłuszczu, węglowodanów, witaminy D3, wapnia i fosforu. Oceniono gęstość mineralną kości (Bone Mineral Density − BMD) w odcinku lędźwiowym (L1-L4). Wynik wyrażono, jako wartość standaryzowaną Z-score. W celu określenia stanu odżywienia dokonano pomiarów antropometrycznych (masa i wysokość ciała oraz BMI). Wykonano następujące obliczenia statystyczne: analizy opisowe, test Manna-Whitneya, test t-Studenta, korelację Spearmana, oraz jednoczynnikową analizę wariancji ANOVA. Wyniki: Badani pacjenci nie spełniali opracowanych dla chorych na mukowiscydozę zaleceń żywieniowych. W diecie zaobserwowano niedobory energii (88% normy), białka (82%), wapnia (78%) oraz witaminy D3 (71%). Wykazano nadmierne spożycie fosforu (142%). Stan odżywienia (parametry antropometryczne) badanej grupy był obniżony i w sposób statystycznie istotny różnił się od grupy referencyjnej (p<0,001). Chłopcy charakteryzowali się znacznie niższą masą ciała (p=0,019) iwysokością (p=0,036) niż dziewczęta, a także niższą kalorycznością diety (p=0,023) oraz zawartością węglowodanów (p=0,005). Dietę dziewcząt cechowała mniejsza zawartość witaminy D3 w diecie (p<0,001) w porównaniu do chłopców. Średnia wartość gęstości mineralnej kości w całej grupie była obniżona i wynosiła -0,95±1,17. Zaobserwowano tendencję do obniżania się BMD wraz z wiekiem. Stan odżywienia wyrażony jako BMI wykazał statystycznie istotną korelację z gęstością mineralną kości, zarówno u dziewcząt (p<0,001), jak i u chłopców (p=0,020). Wnioski: Pacjenci z CF nie przestrzegali opracowanych dla nich zaleceń dietetycznych. Zaobserwowano istotne różnice między dziewczętami i chłopcami. Stan odżywienia (BMI), wykazał korelację z gęstością mineralną kości (BMD), co wymaga intensywnej terapii żywieniowej, zgodnie z opracowanymi rekomendacjami.
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Content available remote Thermal utilization of mixtures of bone waste
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EN
The results of a research related to the physico - chemical properties of the mixture of bone - waste and their ingredients have been presented. The mixtures was made up from waste: bovine bones, pork bones, bone sludge and bone meal. The content of the individual waste in the mixtures was selected on the basis of the heat of the combustion of the mixture and the amount of the waste produced in a meat processing plant. The heat of the combustion has been determined by the calorimeter, the content of phosphorus by spectrophotometric method, calcium by titration and phase composition by X - ray diffraction.The investigations confirmed that pork bones have the highest heat of the combustion 17 MJ/kg because of a big amount of fats. The analyzed waste has contained on average 16.5 wt % phosphorus and above 30 wt % calcium. X - ray diffraction method has proved that in bone waste one phase - hydroxyapatite occurs.
EN
Introduction: Thyroidectomy is a common surgery performed especially in treatment of multinodular goitre. The most common post-thyroidectomy complication is a postoperative hypocalcaemia, and the percentage of postoperative hypoparathyroidism could reach even 50%. Tested group and methods: A forward-looking, randomized testing was done on a group of 113 women being subject to multinodular goitre surgery. In this article, we wish to present an analysis of the results obtained in the control group, focusing on the predicative factors which determine the development of postoperative hypocalcaemia. Obtained results: The rate of postoperative biochemical hypocalcaemia development was significantly higher in the group of patients, where the preoperative calcium concentration was lower than 2,4 mmol/l. In that group, the development of biochemical hypocalcaemia was observed in 93,7% of cases (30 out of 32 patients), in comparison with 65,3% (17 out of 26) in the group of higher preoperative concentration of calcium. The highest risk of occurrence of postoperative hypocalcaemia was borne by the total thyroidectomy, while the lowest one by the subtotal thyroid lobectomy of one lobe only. Conclusions: A higher preoperative concentration of calcium in blood serum is related to the lower rate of occurrence of postoperative biochemical hypocalcaemia. However, no such correlation was revealed in the case of postoperative symptomatic hypocalcaemia. Lack of correlation was determined between the preoperative concentration of TSH and FT4 in blood serum and the rate of occurrence of postoperative hypocalcaemia, both symptomatic and asymptomatic. The performed statistics did not reveal a relation between the postoperative hypocalcaemia and the duration of the surgery, but a significant correlation was stated with the scope of the performed surgery. Revealing a relation between the rate of occurrence of postoperative hypocalcaemia and the experience of the surgeon performing the surgery was not successful.
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Content available remote Toxicological and cytophysiological aspects of lanthanides action.
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EN
Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.
EN
The choice of bottled waters available for sale is large. The assessment of their mineral composition was based on the results of 120 natural waters and 46 mineral waters (in relation to the hydrogeological classification of water mineralization). Significant diversity was found in terms of the basic mineral composition, and in many cases also a wealth of microcompounds (e.g. fluorides, iodine, selenium), which have a positive effect on the human health. Both the deficiency and excess of the water consumed and the amount of contained ingredients have an influence on the human health. While choosing water, it is worth considering the volume of water consumed, the age and health of the consumer, season of year, activity, type of diet, taken dietary supplements, vitamins and medicines. The information on the label is sufficient to choose the water suited to the individual needs. The waters with high mineralization and/or with large concentrations of microcompounds should be used after medical consultations to determine their use: specify the area of application and recommended drinking amount and frequency.
EN
The mechanical link coupling cytoskeletal and contractile proteins to the sarcolemma of smooth muscle cells is essential for transmitting tension from the cell's interior to exterior. In addition to the well-characterized actin-integrin associations present in adhaerens junctions, our recent work has postulated the existence of a reversible annexin-dependent membrane-cytoskeleton complex, forged in response to a rise in intracellular Ca2+ concentration following smooth muscle cell stimulation (Babiychuk et al., J. Biol Chem. 1999, 274, 35191-35195). Detailed biochemical characterization of the interactions responsible for the formation of this complex revealed that annexins II and VI interact with actomyosin, or detergent-insoluble glycosphingolipid-enriched membrane domains (rafts) purified from smooth muscle, in a concentration- and Ca2+-dependent manner. Annexin II interacted with lipid rafts with high Ca2+-sensitivity, while for annexin VI this interaction required non-physiologically high concentrations of free Ca2+. However, the Ca2+-sensitivity of the latter interaction strongly increased in the presence of purified smooth muscle actomyosin. The detailed biochemical analysis of the interactions occurring between annexin II, annexin VI, actomyosin and rafts suggests that annexins regulate sarcolemmal organization during smooth muscle cell contraction.
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Content available remote Structure and functions of plant calcium-dependent protein kinases
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EN
Calcium ions as second messengers play an essential role in many important cellular processes. In plants, transient changes in calcium content in the cytosol (calcium signatures) have been observed during growth, development and under stress conditions. Such diverse functions require many different calcium sensors. One of the largest and most differentiated group of calcium sensors are protein kinases, among them calcium-dependent protein kinases (CDPKs) which were identified only in plants and protists. CDPKs have a regulatory domain which is able to bind calcium ions. For regulation of CDPKs activities not only calcium ions but also specific phospholipids and autophosphorylation are responsible. CDPKs have many different substrates, which reflects the diversity of their functions. Potential protein substrates of CDPK are involved in carbon and nitrogen metabolism, phospholipid synthesis, defense responses, ion and water transport, cytoskeleton organization, transcription and hormone responses. Presently, participation of CDPKs in stress signal transduction pathways (e.g., cold, drought, high salinity, wounding) is intensively studied in many laboratories. An intriguing, but still not fully clarified problem is the cross-talk via CDPKs among different signaling pathways that enables signal integration at different levels and ensure appropriate downstream responses.
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