Chitosan-glucan complex hollow fibers reinforced collagen wound dressing embedded with aloe vera. Part I: Preparation and characterization.

Collagen (CO)/chitosan-glucan complex (CSGC) hollow fibers encapsulated aloe vera (AV) dressing scaffold (CO/CSGC@AV) were fabricated for the first time by the freeze-dried process. Extraction process, morphology, mechanical properties, pore size, porosity, swelling ability, and degradation behavior of composites scaffold were investigated. CSGC hollow fibers were extracted from mycelium of Schizophyllum commune CSGC hollow fiber exhibited inner diameter of (600 ±â€¯250 nm) and outer fiber diameter of (2.5 ±â€¯0.5 µm). The results of swelling and hydrolytic degradation studies demonstrated that the physicochemical of CO/CSGC@AV was significantly enhanced by CSGC in a concentration-dependent manner. The mechanical property of the CO/CSGC@AV was improved after encapsulated AV into CSGC hollow fibers compared with native CO. The pore size and porosity of the CO/CSGC@AV were slightly decreased in the presence of AV. All these results suggested that the new dressing scaffold has a potential for clinical skin regeneration, particularly for infected chronic wounds and ulcers.

Semi-continuous ultrasonic sounding and changes of ultrasonic signal characteristics as a sensitive tool for the evaluation of ongoing microstructural changes of experimental mortar bars tested for their ASR potential.

Semi-continuous ultrasonic sounding of experimental mortar bars used in the accelerated alkali silica reactivity laboratory test (ASTM C1260) is proposed as a supplementary measurement technique providing data that are highly sensitive to minor changes in the microstructure of hardening/deteriorating concrete mixture. A newly designed, patent pending, heating chamber was constructed allowing ultrasonic sounding of mortar bars, stored in accelerating solution without necessity to remove the test specimens from the bath during the measurement. Subsequent automatic data analysis of recorded ultrasonic signals proved their high correlation to the measured length changes (expansion) and their high sensitivity to microstructural changes. The changes of P-wave velocity, and of the energy, amplitude, and frequency of ultrasonic signal, were in the range of 10-80%, compared to 0.51% change of the length. Results presented in this study thus show that ultrasonic sounding seems to be more sensitive to microstructural changes due to ongoing deterioration of concrete microstructure by alkali-silica reaction than the dimensional changes.

[Cognitive functions impairment in diabetes mellitus patient]. / Poruchy kognitivních funkcí u pacientu s diabetes mellitus.

An increased research interest in the relation between diabetes mellitus and dementia or deterioration of cognitive functions has been recently noticed. The relatively rich scientific literature in this topic shows that diabetes mellitus itself can cause an impairment of cognitive functions regardless patient's age or the fact whether he has type 1 or type 2 diabetes mellitus. Type 1 diabetes mellitus leads to a psychomotor retardation while type 2 diabetes mellitus tends to be associated with impaired storage of new information. The exact mechanism through which diabetes impairs cognition has not been explained sufficiently yet, but several hypothetical mechanisms which might explain the relation between diabetes and impaired cognition have been proposed. To explain the etiopathogenetic mechanisms underlying the relation between diabetes and dementia, further research, especially research focused on process clinical-imaging studies or clinical-pathological studies is necessary. As far as clinical practice is concerned, it is important to bear in mind that prevention, timely diagnosis and optimum treatment of diabetes may help to reduce incidence of dementia or cognitive functions' impairment.

[Hippocampus, structure of the brain and schizophrenia]. / Hipokampus, morfologie mozku a schizofrenie.

Schizophrenia is a clinically heterogeneous state without clearly defined pathogenesis. This limits the classification approaches with consequent lack of ability for individual treatment strategies. It becomes evident that hippocampus is a key structure in the neuropathology of schizophrenia and a concept of hippocampal reduction as an endophenotype of schizophrenia was established. The biggest support came from MRI volumetric studies. Despite that, due to some inconsistent findings, clinical consequences of hippocampal shrinkage are not yet clear. Contemporary methods of brain imaging (computation morphometry, voxel-based morphometry) could help us to outline the concept of schizophrenia and to clarify the clinical consequences of brain structure changes.

Sorption of Cesium on smectite-rich clays from the Bohemian Massif (Czech Republic) and their mixtures with sand.

Sorption is an important process for the transport of radionuclides through backfill materials in a radioactive waste underground repository. Within this study, sorption of Cs on selected Czech clay materials and their mixtures with sand was investigated by batch tests. The experiments were performed under oxic conditions at 25 degrees C. Synthetic groundwater as a liquid phase and unconditioned clays (as they were provided by their producer) were used to reach the natural conditions as close as possible. Distribution ratios (Rds) of Cs for all selected clays rise with increase of the clay fraction in clay/sand mixtures in agreement with previous works studying sorption behaviour of such mixtures. The rise of Rds is from 10(2) cm3 g(-1) for mixtures with 80% of sand to 10(3) cm3 g(-1) for pure clays. There are significant differences between natural and technologically modified clays.

[Present status and future of imaging methods in neuropsychiatry]. / Soucasnost a budoucnost zobrazovacích metod v neuropsychiatrii.

Introduction describes historical relations between neurology and psychiatry. Both disciplines are now much nearer to each other than before--they have received similar diagnostic tools and they have similar therapeutic methods. Psychiatry is considered to be an integral part of neuroscience. The article reviews findings on the structural and functional changes accompanying the most serious psychiatric diseases and the growing role of the brain imaging methods is depicted.