Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Prague Med Rep ; 123(4): 215-224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36416460

RESUMO

There is a clear experience in clinical practice: boys with a diagnosis of ADHD are clearly in greater numbers than girls. It is noteworthy that even in the "older" review articles, the cause of sex-dependent incidence is not mentioned. If we accept the neurodevelopmental hypothesis of such disorder, then the possible genetic predisposition breaks down into two separate groups. On the genome of an individual with ADHD and on the genome of the parents. However, it cannot be overlooked that the incidence of ADHD (3-7%) corresponds to the incidence and sex differences of the number of newborns born at a certain risk (premature birth, immaturity, hypotrophy, hypoxic-ischemic syndrome, low birth weight, etc.). This association of possible genetic predisposition with "external" risks in the genesis of ADHD raises the question of whether a higher incidence of ADHD, as well as higher morbidity and mortality in males, are a) the norm and the female is privileged, or b) the female is the norm and the male is handicapped. The picture of ADHD includes various cognitive dysfunctions with one possible cause in norepinephrine and dopamine insufficiency. Experimental work shows that in response to stress females release more catecholamines in the CNS than males. Since catecholamines stimulate membrane Na+ K+ ATPase activity, this means both the value of the membrane potential and the threshold for activation is increased. Females are more successful in responding to and adapting to a stressful situation due to their higher production of noradrenaline in the CNS.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Caracteres Sexuais , Recém-Nascido , Gravidez , Humanos , Feminino , Masculino , Incidência , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Predisposição Genética para Doença , Norepinefrina , Catecolaminas
2.
Prague Med Rep ; 123(1): 5-19, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35248160

RESUMO

The objective of the study was to determine the effects of inferior alveolar nerve transection on inorganic components in mandibular molars of the rat. We used 26 male laboratory rats of the Wistar strain for the study, age 7-9 weeks. The rats were divided in three groups. The control group (intact) included 6 rats. The surgery was performed under general anesthesia. The experimental group included (group with the nerve transected on the left) included 12 rats. The sham group (group with the nerve prepared without transection) included 8 rats. The animals were sacrificed after 4 weeks. Molars from the left and right sides of the mandible were extracted. Element content levels were determined using inductively coupled plasma mass spectrometry. The following elements were determined in all samples: magnesium (Mg), sodium (Na), potassium (K), calcium (Ca), zinc (Zn), and strontium (Sr). The nerve transection caused: a reduction of the contents of Ca and Sr in the mandibular molars; an increase in the contents of Mg and Zn; a difference arrangement of both sides for Na. The surgery approach itself caused a decrease in the contents of Na and K in the experimental and sham groups; the difference in K in M3 between the left and right sides disappeared due to the surgery. Our results have confirmed the hypothesis of inferior alveolar nerve transection having an effect on inorganic components in mandibular molars in the rat.


Assuntos
Mandíbula , Nervo Mandibular , Animais , Masculino , Mandíbula/cirurgia , Nervo Mandibular/fisiologia , Nervo Mandibular/cirurgia , Dente Molar/cirurgia , Ratos , Ratos Wistar
3.
Polymers (Basel) ; 14(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35012221

RESUMO

Nowadays, additive manufacturing-also called 3D printing-represents a well-established technology in the field of the processing of various types of materials manufacturing products used in many industrial sectors. The most common type of 3D printing uses the fused filament fabrication (FFF) method, in which materials based on thermoplastics or elastomers are processed into filaments. Much effort was dedicated to improving the properties and processing of such printed filaments, and various types of inorganic and organic additives have been found to play a beneficial role. One of them, calcium carbonate (CaCO3), is standardly used as filler for the processing of polymeric materials. However, it is well-known from its different applications that CaCO3 crystals may represent particles of different morphologies and shapes that may have a crucial impact on the final properties of the resulting products. For this reason, three different synthetic polymorphs of CaCO3 (aragonite, calcite, and vaterite) and commercially available calcite powders were applied as fillers for the fabrication of polymeric filaments. Analysis of obtained data from different testing techniques has shown significant influence of filament properties depending on the type of applied CaCO3 polymorph. Aragonite particles showed a beneficial impact on the mechanical properties of produced filaments. The obtained results may help to fabricate products with enhanced properties using 3D printing FFF technology.

4.
Materials (Basel) ; 14(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34640301

RESUMO

Most of the historical and old building stock in Europe are constructed from masonry, when brick, stones, or their combination are bound with traditional mortars. Rising damp, due to accompanying effects, is the main factor influencing the quality of indoor climate as well as having an important impact on the durability of masonry structures. In this study, new types of lightweight concrete with waste aggregate content as a suitable material for remediation of damp damaged masonries were designed and tested. Alternative aggregate served as silica sand substitution in the range of 0-100 vol.%. Basic structural properties, mechanical resistance, water, and water vapor transport properties were measured after 28 days of water curing and were compared with dense reference concrete and with traditional masonry materials as well. Moreover, the porous structure of produced concretes and changes caused by usage of alternative aggregate usage were evaluated with the mercury intrusion porosimetry (MIP) technique. Obtained experimental data showed the suitability of modified concretes with 25-50 vol.% of waste aggregate content to ensure acceptable strength and hydric properties, and these properties were found to be comparable with masonry structures and materials used in the past.

5.
Front Endocrinol (Lausanne) ; 12: 613983, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953692

RESUMO

The equilibrium and reciprocal actions among appetite-stimulating (orexigenic) and appetite-suppressing (anorexigenic) signals synthesized in the gut, brain, microbiome and adipose tissue (AT), seems to play a pivotal role in the regulation of food intake and feeding behavior, anxiety, and depression. A dysregulation of mechanisms controlling the energy balance may result in eating disorders such as anorexia nervosa (AN) and bulimia nervosa (BN). AN is a psychiatric disease defined by chronic self-induced extreme dietary restriction leading to an extremely low body weight and adiposity. BN is defined as out-of-control binge eating, which is compensated by self-induced vomiting, fasting, or excessive exercise. Certain gut microbiota-related compounds, like bacterial chaperone protein Escherichia coli caseinolytic protease B (ClpB) and food-derived antigens were recently described to trigger the production of autoantibodies cross-reacting with appetite-regulating hormones and neurotransmitters. Gut microbiome may be a potential manipulator for AT and energy homeostasis. Thus, the regulation of appetite, emotion, mood, and nutritional status is also under the control of neuroimmunoendocrine mechanisms by secretion of autoantibodies directed against neuropeptides, neuroactive metabolites, and peptides. In AN and BN, altered cholinergic, dopaminergic, adrenergic, and serotonergic relays may lead to abnormal AT, gut, and brain hormone secretion. The present review summarizes updated knowledge regarding the gut dysbiosis, gut-barrier permeability, short-chain fatty acids (SCFA), fecal microbial transplantation (FMT), blood-brain barrier permeability, and autoantibodies within the ghrelin and melanocortin systems in eating disorders. We expect that the new knowledge may be used for the development of a novel preventive and therapeutic approach for treatment of AN and BN.


Assuntos
Autoanticorpos , Transtornos da Alimentação e da Ingestão de Alimentos/imunologia , Microbioma Gastrointestinal/imunologia , Grelina/imunologia , Insulina/imunologia , Leptina/imunologia , Hormônios Estimuladores de Melanócitos/imunologia , Neuropeptídeo Y/imunologia , Transtornos da Alimentação e da Ingestão de Alimentos/microbiologia , Humanos
6.
Polymers (Basel) ; 13(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375094

RESUMO

Epoxy resins are characterized by excellent properties such as chemical resistance, shape stability, hardness and heat resistance, but they present low flame resistance. In this work, the synthesized derivatives, namely hexacyclohexylamino-cyclotriphosphazene (HCACTP) and novel diaminotetracyclohexylamino-cyclotriphosphazene (DTCATP), were applied as curing agents for halogen-free flame retarding epoxy materials. The thermal properties and combustion behavior of the cured epoxy resins were investigated. The obtained results revealed that the application of both derivatives significantly increased flame resistance. The epoxy resins cured with HCACTP and DTCATP exhibited lower total heat release together with lower total smoke production compared to the epoxy materials based on conventional curing agents (dipropylenetriamine and ethylenediamine). Comparing both derivatives, the HCACTP-cured epoxy resin was found to provide a higher flame resistance. The designed novel class of epoxy materials may be used for the preparation of materials with improved flame resistance properties in terms of flame spreading and smoke inhibition.

7.
Materials (Basel) ; 13(21)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167529

RESUMO

Reclaimed asphalt pavement (RAP) is a valuable commodity originating during processes of road/highways rehabilitations, resurfacing in the cases of the revelation of underneath-placed layers. Removed material can be successfully recycled and utilized as a supplementing material for new hot asphalt mixes. However, its dosages are limited because of variations in properties of aged bitumen compared to fresh material and, thus, a significant amount of waste material is remaining as waste products. Nonetheless, this commodity may find usage in the construction industry that suffers from a shortage of high-quality and easily available aggregates. This work aimed to investigate the optimal substitution of mined natural aggregate with commonly available RAP in order to produce composites with the comparable mechanical performance of reference ordinary Portland concrete. The aggregate substitutions up to 100% with RAP have been studied with a combination of mechanical and analytical techniques. Obtained experimental data showed changes in the porous structure, mineralogy, and in the amount of formed cement-related hydration products that influenced the mechanical performance of produced composites. Composite with 10% of natural aggregate substitution with RAP has shown the strength class C16/20 after 28 days of water curing, according to the EN 206-1. Such innovative products could be utilized in the construction industry. The usage of waste RAP could contribute to preservation of our environment for future generations.

8.
J Musculoskelet Neuronal Interact ; 20(2): 272-281, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32481243

RESUMO

OBJECTIVE: The aim of the study was to test the effect of transecting the inferior alveolar nerve on the inorganic bone component of the rat mandible. METHODS: 7-9 weeks old, male Wistar rats were used for the study. The animals were divided in 3 groups: control, experimental (nerve was transected) and sham (nerve was only prepared but not transected). After 4 weeks, the animals were killed, their teeth were extracted, and the mandibular bone was divided in 4 parts. Inductively coupled plasma mass spectrometry was used to the levels of 7 elements in the bone. RESULTS: The study results demonstrate that transection of the inferior alveolar nerve caused a decrease in calcium, iron, and strontium, and an increase of zinc. It caused the differences in potassium contents between the sides was significantly lower in the experimental group. The increase in the magnesium content, and decrease of sodium and potassium in the experimental group, as well as differences in the contents of: magnesium, sodium, potassium, iron and zinc between individual locations in the mandible are associated with the surgical approach. CONCLUSION: The results support our hypothesis - that sensory innervation has an impact on the inorganic component of the mandibular bone.


Assuntos
Mandíbula/química , Mandíbula/inervação , Nervo Mandibular/fisiologia , Animais , Axotomia , Masculino , Ratos , Ratos Wistar
9.
Neuro Endocrinol Lett ; 41(7-8): 392-400, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33754596

RESUMO

OBJECTIVES: Changes in the hippocampus induced by water intoxication were studied using fluorescence microscopy (FM) and magnetic resonance imaging (MRI). METHODS: In three animals (rats), intracellular/extracellular distribution of Evans blue (EB) in cerebral cortex and hippocampus of both hemispheres was revealed by injection of EB into the internal carotid artery (ICA) in hyperhydrated rats (water intoxication, WI). A total of 8 experimental rats were used for the MRI study. The animals were scanned before WI, then the experimental brain edema was induced by WI and MR scanning was performed at day 1 and day 8 after WI. Besides standard T2-weighted imaging an apparent diffusion coefficient (ADC) and transverse relaxation time (T2) were evaluated. RESULTS: Hyperhydration brought about the largest intracellular deposits of EB in CA3 hippocampal region, followed by the cerebral cortex and CA1 hippocampal region with the lowest amount of intracellular EB in the dentate gyrus. A higher apparent diffusion coefficient (corresponding to a vasogenic edema) was found the first day after hyperhydration in the cortex and in the CA1 and CA3 regions with no changes in dentate gyrus. CONCLUSION: Both FM and MRI confirmed a selectively higher vulnerability to hyperhydration and hyponatremia (achieved by water intoxication) of the hippocampal cells compared to dentate gyrus cells.


Assuntos
Edema Encefálico , Hipocampo , Animais , Encéfalo , Edema Encefálico/diagnóstico por imagem , Azul Evans , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Microscopia de Fluorescência , Ratos , Intoxicação por Água
10.
Materials (Basel) ; 12(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671520

RESUMO

In this paper, crushed lava granulate was used as full silica sand replacement in composition of repair mortars based on hydrated lime, natural hydraulic lime, or cement-lime binder. Lava granules were analyzed by X-ray fluorescence analysis (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Particle size distribution of both silica and lava aggregates was assessed using standard sieve analysis. Hygrothermal function of the developed lightweight materials was characterized by the measurement of complete set of hygric, thermal, and structural parameters of the hardened mortar samples that were tested for both 28 days and 90 days cured specimens. As the repair mortars must also meet requirements on mechanical performance, their compressive strength, flexural strength, and dynamic Young's modulus were tested. The newly developed mortars composed of lava aggregate and hydrated lime or natural hydraulic lime met technical, functional, compatibility, and performance criteria on masonry and rendering materials, and were found well applicable for repair of historically valuable buildings.

11.
Materials (Basel) ; 12(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295888

RESUMO

Mechanically-activated wood-based biomass ash (WBA) was studied as a potential active admixture for design of a novel lime-pozzolan-based mortar for renovation purposes. The replacement ratio of lime hydrate in a mortar mix composition was 5%, 10%, and 15% by mass. The water/binder ratio and the sand/binder ratio were kept constant for all examined mortar mixes. Both binder constituents were characterized by their powder density, specific density, BET (Brunauer-Emmett-Teller), and Blaine specific surfaces. Their chemical composition was measured by X-ray fluorescence analysis (XRF) and mineralogical analysis was performed using X-ray diffraction (XRD). Morphology of WBA was investigated by scanning electron microscopy (SEM) and element mapping was performed using an energy dispersive spectroscopy (EDS) analyzer. The pozzolanic activity of WBA was tested by the Chapelle test and assessment of the Portlandite content used simultaneous thermal analysis (STA). For the hardened mortar samples, a complete set of structural, mechanical, hygric, and thermal parameters was experimentally determined. The mortars with WBA admixing yielded similar or better functional properties than those obtained for traditional pure lime-based plaster, pointing to their presumed application as rendering and walling renovation mortars. As the Chapelle test, STA, and mechanical test proved high pozzolanity of WBA, it was classified as an alternative eco-efficient low-cost pozzolan for use in lime blend-based building materials. The savings in CO2 emissions and energy by the use of WBA as a partial lime hydrate substitute in mortar composition were also highly appreciated with respect to the sustainability of the construction industry.

12.
Materials (Basel) ; 12(10)2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117225

RESUMO

Two waste fired brick powders coming from brick factories located in Argentine and Czech Republic were examined as alternative mineral admixtures for the production of blended cements. In pastes composition, local Portland cements (Argentine and Czech) were substituted with 8-40%, by mass, with powdered ceramic waste. For the ceramic waste-Portland cement system, workability, the heat released, pozzolanity, specific density, compressive strength, hydrated phases, porosity, and pore size distribution were tested. The relevance of the dilution effect, filler effect, and pozzolanic activity was analyzed to describe the general behavior of the pozzolan/cement system. The properties and performance of cement blends made with finely ground brick powder depended on the composition of ceramic waste and its reactivity, the plain cement used, and the replacement level. Results showed that the initial mini-slump was not affected by a low ceramic waste replacement (8% and 16%), and then it was decreased with an increase in the ceramic waste content. Brick powder behaved as a filler at early ages, but when the hydration proceeded, its pozzolanic activity consumed partially the calcium hydroxide and promoted the formation of hydrated calcium aluminates depending on the age and present carbonates. Finally, blended cements with fired brick powder had low compressive strength at early ages but comparable strength-class at later age.

13.
Materials (Basel) ; 12(6)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917584

RESUMO

The goal of the paper was development and testing of a novel type of ternary blended binder based on lime hydrate, metakaolin, and biomass ash that was studied as a binding material for production of lightweight mortar for renovation purposes. The biomass ash used as one of binder components was coming from wood chips ash combustion in a biomass heating plant. The raw ash was mechanically activated by grinding. In mortar composition, wood chips ash and metakaolin were used as partial substitutes of lime hydrate. Silica sand of particle size fraction 0⁻2 mm was mixed from three normalized sand fractions. For the evaluation of the effect of biomass ash and metakaolin incorporation in mortar mix on material properties, reference lime mortar was tested as well. Among the basic physical characterization of biomass ash, metakaolin and lime hydrate, specific density, specific surface, and particle size distribution were assessed. Their chemical composition was measured by X-Ray fluorescence analysis (XRF), morphology was examined using scanning electron microscopy (SEM), elements mapping was performed using energy dispersive spectroscopy (EDS) analyser, and mineralogical composition was tested using X-Ray diffraction (XRD). For the developed mortars, set of structural, mechanical, hygric, and thermal properties was assessed. The mortars with ternary blended binder exhibited improved mechanical resistance, lower thermal conductivity, and increased water vapor permeability compared to the reference lime mortar. Based on good functional performance of the produced mortar, the tested biomass ash could potentially represent a novel sustainable alternative to other pozzolans commonly used in construction industry. Moreover, reuse of biomass ash in production of building materials is highly beneficial both from the environmental and economic reasons especially taking into account circular economy principles. The ternary blended binder examined in this paper can find use in both rendering and walling repair mortars meeting the requirements of culture heritage authorities and technical standards.

14.
Neuro Endocrinol Lett ; 40(7-8): 319-324, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32304368

RESUMO

OBJECTIVES: Accurate values of the intracranial pressure (ICP) and mean arterial pressure (MAP) are the prerequisite for calculating cerebral perfusion pressure (CPP). Increased ICP values decrease CPP. The origin of ICP increase in the clinical cases after brain ischemia and diffuse brain injury is the cellular brain edema (CE). Short-term monitoring of ICP and MAP is possible only in the unconscious patients, in experiments with rats it used to be possible only in general anesthesia. Long-term monitoring of ICP or MAP in the clinical practice is not possible. We therefore introduce an experimental model with telemetric monitoring. METHODS: ICP (subdurally) and MAP (intracarotically) were monitored in freely moving rats for 72 hours by DSI™ (Data Sciences International) telemetry system. The control group consisted of 8 rats, the experimental group had 8 animals with CE-induced by water intoxication. RESULTS: The mean MAP, ICP and CPP values were significantly higher in the experimental group. Average values of MAP were 19.9 mmHg (18%), ICP 5.3 mmHg (55%), CPP 14.5 mmHg (15% higher). CONCLUSION: The results of the pilot study verified possibilities of long-term telemetric monitoring of the mean arterial and intracranial pressures for the determination of current cerebral perfusion pressure in freely moving rats under physiological conditions and with increased intracranial pressure due to the induced cerebral edema. Detailed analysis of the course of the curves in the experimental group revealed episodes of short-term CPP reduction below the optimum value of 70 mmHg. Interpretation of these episodes requires simultaneous monitoring of rat behavior.


Assuntos
Pressão Arterial , Edema Encefálico/fisiopatologia , Pressão Intracraniana , Monitorização Ambulatorial/métodos , Telemetria/métodos , Animais , Circulação Cerebrovascular , Monitorização Ambulatorial/instrumentação , Projetos Piloto , Ratos , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Telemetria/instrumentação
15.
Neuro Endocrinol Lett ; 40(6): 249-256, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32200583

RESUMO

OBJECTIVES: A novel method of long-term telemetric monitoring of mean arterial pressure (MAP) and intracranial pressure (ICP) for the determination of current cerebral perfusion pressure (CPP) and the time course of ICP in freely moving rats under physiological conditions and with increased ICP due to the induced cerebral edema were studied. METHODS: The brain edema, that caused volume enlargement and ICP elevation was achieved in entirely experimental conditions without any parallel pathological process. Vasogenic/extracellular edema was induced by osmotic blood-brain barrier disruption (BBBd) and for induction of cytotoxic/intracellular edema the water intoxication model (WI) was used. RESULTS: The results showed significantly elevated values of ICP both in conditions of osmotic blood-brain barrier disruption (BBBd model) and cytotoxic/intracellular edema (WI model) compared to intact rats. The average values of ICP were significantly higher in WI model compared to osmotic BBBd model. Distinct pattern of elevated ICP, related to the selected way of experimental brain edema induction, was found. In the experimental model of osmotic BBB disruption, the elevation of ICP started earlier but was of very short duration. In WI model the elevation of ICP was present during the whole period of monitoring. CONCLUSION: Our results indicate that purely experimental models of brain edema (WI, BBBd) without any parallel pathological process can compromise the basic brain homeostatic activity.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/etiologia , Edema Encefálico/fisiopatologia , Hipertensão Intracraniana/complicações , Intoxicação por Água/complicações , Animais , Encéfalo/fisiopatologia , Edema Encefálico/diagnóstico , Circulação Cerebrovascular/fisiologia , Hipertensão Intracraniana/diagnóstico , Hipertensão Intracraniana/fisiopatologia , Pressão Intracraniana/fisiologia , Masculino , Monitorização Fisiológica/métodos , Ratos , Ratos Wistar , Telemetria , Intoxicação por Água/diagnóstico , Intoxicação por Água/fisiopatologia
16.
Neuro Endocrinol Lett ; 39(4): 310-314, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30531705

RESUMO

OBJECTIVES: Effect of recombinant human erythropoietin (rhEPO) on spontaneous motor activity was tested in young rats after intraperitoneal (i.p.) administration of rhEPO, followed by induction of cellular brain edema (CE). Induced changes in the spontaneous horizontal locomotor activity was studied by open field test (OFT). METHODS: CE was induced by water intoxication (WI) using standard method of fractional hyperhydration accompanied with desmopressin administration. Using the accepted method of OFT average time spent in locomotion (s) was determined. 48 young rats at the age of 25, and 35 days were divided into three groups - controls, rats after WI (OFT followed after 44 hours), and rats administered with rhEPO prior to application WI (OFT after 48 hours). RESULTS: In 35-day-old rats rhEPO administration increased the spontaneous locomotor activity, previously decreased by cellular edema. In 25-day-old rats, rhEPO administration prior to the induced CE, decreased spontaneous locomotor activity. CONCLUSION: Presented results demonstrate the neuroprotective capacity of rhEPO, manifested by elimination of the suppressive influence of CE on the locomotion in 35-day-old rats. In 25-day-old rats the neuroprotective effect was not present. These results confirmed that the 10 day interval in the development may represent a different stage of brain maturation in the relation to the neuroprotective effect of rhEPO.


Assuntos
Comportamento Animal/efeitos dos fármacos , Edema Encefálico/fisiopatologia , Eritropoetina/farmacologia , Locomoção/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Intoxicação por Água/fisiopatologia , Fatores Etários , Animais , Masculino , Ratos , Ratos Wistar , Proteínas Recombinantes/farmacologia
17.
Waste Manag ; 80: 89-100, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30455031

RESUMO

Wood chips ash coming from biomass heating plant is studied as an eco-friendly mineral admixture in mortar mix design. The raw material was mechanically activated by milling in a vibratory disc mill to a degree of fineness comparable to cement. For the mortars with ash dosage, basic physical, mechanical, hygric, and thermal properties is accessed. The mortars with partial Portland cement replacement with wood chips ash exhibited good functional properties for all studied ash dosages. With increasing amount of the ash used, the average pore diameter decreased due to the partial filler effect of WCHA in mortar mix. The strength activity index was very high for all studied mortars and gave evidence of the wood chips ash pozzolanity. The pozzolan effectiveness coefficient varied from 1.52 to 0.59, which proved the pozzolanity of the studied ash and synergic effects in the Portland cement-ash-water system. The results of leaching tests showed, the chlorides contained in ash were safely immobilized in the silicate matrix. The environmental evaluation revealed decrease in both carbon dioxide production and energy consumption by the use of wood chips ash in mortar mix. For the mortar with 20% substitution of Portland cement with wood chips ash, it represents 15% of CO2 and 16% of energy, as compared with the reference mortar mix. As the developed mortars possess good functional and environmental parameters the analyzed wood chips ash can be considered as an eco-efficient low-cost alternative to other pozzolans for production of blended binders.


Assuntos
Cinza de Carvão , Madeira , Biomassa , Materiais de Construção , Minerais
18.
Neuro Endocrinol Lett ; 39(3): 209-218, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30431738

RESUMO

OBJECTIVES: This paper presents our own rat model of the cellular brain edema, induced by water intoxication (WI). The basic principle of the model is an osmotic imbalance in the cell membrane followed by an intracellular flow of sodium and simultaneous accumulation of water leading to the subsequent increase of BBB permeability. METHODS: The usefulness of the model was tested in precisely specified conditions whose results were clearly expressed. The procedure determined both how WI induces cellular edema as well as the disturbances caused by cellular edema. RESULTS: The evidence of existing cellular edema with increased BBB permeability was proved by intracellular accumulation of intravital dye with a large molecular size; increased brain-water content was confirmed by using the dry/wet weight method and by the decrease in CT density; the elevated intracranial pressure (ICP) due to the expanding volume was determined by continuous monitoring the ICP; the structural lesions were proved by identification of the myelin disintegration; and the impaired nervous functions was demonstrated by the of open field test method. CONCLUSION: Our experimental model can help the future studies of pathophysiology of cellular brain edema and is suitable for testing neuroprotective agents.


Assuntos
Comportamento Animal , Edema Encefálico/fisiopatologia , Modelos Animais de Doenças , Hipertensão Intracraniana/fisiopatologia , Locomoção , Ratos , Intoxicação por Água/fisiopatologia , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Edema Encefálico/etiologia , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Azul Evans , Hipertensão Intracraniana/etiologia , Hipertensão Intracraniana/metabolismo , Hipertensão Intracraniana/patologia , Masculino , Bainha de Mielina/patologia , Permeabilidade , Ratos Wistar , Tomografia Computadorizada por Raios X , Intoxicação por Água/complicações , Intoxicação por Água/metabolismo , Intoxicação por Água/patologia
19.
Prague Med Rep ; 119(4): 137-147, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30779698

RESUMO

The effect of the nervous system on bone remodelling has been described by many studies. Sensory and autonomic nerves are present in the bone. Immunohistochemical analysis of the bone have indicated the presence of neuropeptides and neurotransmitters that act on bone cells through receptors. Besides carrying sensory information, sensory neurons produce various neuropeptides playing an important role in maintaining bone and tooth pulp homeostasis, and dentin formation. Bone tissue and teeth contain organic and inorganic components. Bone cells enable bone mineralization and ensure its formation and resorption. Studies focused on the effects of the nervous system on the bone are proceeded using various ways. Sensory denervation itself can be achieved using capsaicin causing chemical lesion to the nerve. Surgical ways of causing only sensory lesion to nerves are substantially limited because many peripheral nerves are mixed and contain a motor component as well. From this point of view, the experimental model with transection of inferior alveolar nerve is appropriate. This nerve provides sensory innervation of the bone and teeth of the mandible. The purpose of our paper is to provide an overview of the effects exerted by the nervous system on the inorganic component of the bone and teeth, and also to present an overview of the used experimental models. As we assume, the transection of inferior alveolar nerve could be reflected in changed contents and distribution of chemical elements in the bone and teeth of rat mandible. This issue has not been studied so far.


Assuntos
Polpa Dentária , Dente , Animais , Denervação , Polpa Dentária/inervação , Neurônios Aferentes , Ratos , Dente/inervação
20.
Neuro Endocrinol Lett ; 38(7): 495-501, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29369601

RESUMO

OBJECTIVE: Locomotion, rearing and grooming represent different forms of behaviour and motor activity in rats. In this study, changes in these activities were analysed in relation to impaired function of the nervous system by single and/or concomitant lesions representing an experimental model of the dual diagnosis. METHODS: 32 rats were divided into 4 groups of 8 rats: intact rats, rats with single lesion of peripheral nervous system (PNS) - Marcaine neuropathy, rats with single CNS lesion - cellular brain edema induced by water intoxication, and the concomitant lesions (combination of CNS and PNS lesion in one rat). Water intoxication was performed in a standard way by fractionated hyperhydration. The average time spent by locomotion, rearing and grooming was registered and analyzed using an open field test. RESULTS: All activities of the rats after water intoxication became inhibited due to the generally suppressive effect of brain edema. Lesion of PNS reduced activity in locomotion only, because for rearing and grooming activities, the function of the forelimb is not dominant. Combination of lesions (dual diagnosis) reduced locomotion and rearing activity more than single lesions, and enhances the stressogenic effect, which was manifested by a long periods of grooming. CONCLUSION: Results of our study confirmed the physiological and pathophysiological differences in the movement stereotype between locomotion, rearing and grooming caused by the characteristics and algorithms of the movements, which are inborn to rats - the dominant role of the forelimbs in locomotion, the dominant exploratory activity in rearing, and the precise syntactic movement pattern in grooming.


Assuntos
Comportamento Animal/fisiologia , Edema Encefálico/fisiopatologia , Asseio Animal/fisiologia , Locomoção/fisiologia , Atividade Motora/fisiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Intoxicação por Água/fisiopatologia , Animais , Bupivacaína , Masculino , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...