Structural and functional catalytic characteristics of cross-linked enzyme aggregates (CLEA) are reviewed. Firstly, advantages of enzyme immobilization and existing types of immobilization are described. Then, a wide description of the factors that modify CLEA activity, selectivity and stability is presented. Nowadays CLEA offers an economic, simple and easy tool to reuse biocatalysts, improving their catalytic properties and stability. This immobilization methodology has been widely and satisfactorily tested with a great variety of enzymes and has demonstrated its potential as a future tool to optimize biocatalytic processes.
Gold nanoparticles (AuNPs) were synthesized, in the absence of any reducing agent, using ionizing radiation or ultrasound in aqueous solutions of chloroauric acid (HAuCl4). Chitosan (average molecular weight 158 kDa, degree of deacetylation 90 %) was used as a stabilizing agent. Both techniques yielded AuNPs which were stable in solution at RT for at least 3 months after synthesis. UV-Vis spectroscopy was used to follow substrate decay, nanoparticles formation, size of the gold core and particles stability. Hydrodynamic radii and polydispersion of the chitozan-stabilized AuNPs (i.e. the whole core-shell nanoparticles) were determined by dynamic light scattering. Zeta potential measurements were performed to assess the surface charge and stability of the particles. Influence of synthesis parameters and presence of isopropanol on the formation and properties of the products have been described and reaction mechanisms have been discussed. Radiation and sonochemical methods are demonstrated to be very efficient, fast and easy-to-control methods of synthesizing gold nanoparticles, leaving behind no unreacted reducing agent or unwanted side products, while stabilization by chitosan provides AuNPs with excellent stability and long shelf life.
In the paper influence of electromagnetic field (200 MHz) on biosensor matrix component was shown. Specially designed test bench containing the scanner 3D with the robot was used for electromagnetic field monitoring. The scans of electromagnetic field distribution, before and behind sample were collected. Conformation change of studied protein was monitored by UV spectra. It indicates that fragmentation and aggregation of studied protein might occur with time. The stabilization effect caused by electromagnetic 200 MHz in protein solution was found. The effect was dose dependent (cumulative effect of electromagnetic field) and the differences in the absorption intensity between the control sample and samples after exposition were more visible with time.
Awareness of the role of physical activity in the life full of stress, incorrect sitting position, bad work ergonomics and unhealthy eating habits are reflected in the increasing number of people who perform different amateur sport disciplines. The most popular activities are riding a bike (51%), swimming (28%), jogging (18%), walking (16%), football (14%), volleyball (14%) and fitness (13%). Unfortunately, the increased physical activity is also connected with the increased risk of contusion, injury or overload. Many authors emphasize the significant role of deep muscle stability training in injury prevention, contusion, overload and chronic back pain prevention. The most important role of local muscles is their proportional and equal activation, in order to ensure the correct movement patterns in functional ranges. Weak or insufficient work of one of the links in the chain causes compensatory movement patterns which activate polyarthritis (multijoin) muscles. This phenomenon leads to loosening of stability and movement precision. The consequences include modulation of the Central Nervous System (CNS), chronic pain, deterioration of physical activity, injuries and contusions. The aim of the local muscle training is mutual activation of these muscles in the closed kinematic chain, with the correct body position in its axis, maintaing the neutral position and frequent impulsation of muscles. The aim of this presentation is to show the benefits that can be observed in deep muscle activation and the strengthening of body center in order to prevent sport injuries.
PL
Świadomość roli aktywności fizycznej w życiu przepełnionym stresem, nieprawidłową pozycją siedzącą, złą ergonomią pracy oraz niestosownym odżywianiem wyraża się rosnącą liczbą osób amatorsko trenujących różne dyscypliny sportowe. Najbardziej popularnym sportem jest jazda na rowerze (51%), pływanie (28%) następnie bieganie (18%), spacery (16%), piłka nożna (14%), siatkówka (14%), fitness (13%). Zwiększonej aktywności fizycznej towarzyszy jednak wzrost ryzyka wystąpienia kontuzji oraz przeciążeń. Wielu autorów zwraca uwagę na istotną rolę treningu stabilizacji mięśni głębokich jako prewencji przeciwko kontuzjom, przeciążeniom oraz powstawaniu przewlekłego bólu kręgosłupa. Najważniejszą rolą mięśni lokalnych jest ich proporcjonalna i równomierna aktywacja celem zapewnienia prawidłowych wzorców ruchowych w zakresach funkcjonalnych. Osłabienie lub niewystarczająca praca jednego z ogniw łańcucha wyzwala kompensacyjne wzorce ruchowe aktywizujące mięśnie wielostawowe. Zjawisko to doprowadza do utraty stabilności i precyzji ruchu. Konsekwencją jest również modulacja centralnego układu nerwowego, wystąpienie przewlekłego bólu, pogorszenie sprawności fizycznej, większa podatność na wystąpienie urazów. Istotą treningu mięśni lokalnych jest ich jednoczesna aktywacja, w zamkniętym łańcuchu kinematycznym, z odpowiednim ułożeniem ciała w osi z zachowaniem pozycji neutralnej oraz ich częsta impulsacja. Celem niniejszej prezentacji jest przedstawienie korzyści płynących z aktywacji mięśni głębokich i wzmocnienia „centrum” ciała w prewencji urazów sportowych.
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