PURPOSE: To assess cardiac structural and functional changes induced by competitive amateur cycling. METHODS: Fifty-one young competitive amateur male cyclists and 47 age- and gender-matched control subjects underwent complex transthoracic echocardiographic examination focused on the detailed assessment of cardiac size and function, especially of the left ventricle (LV). Subsequently, spiroergometry was performed in all study participants and its results were compared to echocardiographic data. RESULTS: Higher left ventricular mass indexes due to the greater LV wall thickness and LV end-diastolic diameter were found in amateur cyclists as compared to control subjects. There were no differences with regard to the LV systolic function parameters. However, significantly better indices of LV diastolic function were present in cyclists. A significant correlation between maximal oxygen pulse and LV mass index/height(2.7), LV diastolic parameters and right ventricular size was noted. CONCLUSIONS: Amateur competitive cycling leads to considerable LV structural and functional changes. The increases in LV wall thickness and cavity size together with supranormal diastolic properties are key characteristics of this LV remodeling. As well, LV mass, diastolic function, and RV size are predictors of exercise capacity, indicating an important involvement of these elements in improving cardiac function with endurance training.

• MeSH
• cyklistika fyziologie   MeSH
• funkce levé komory srdeční fyziologie   MeSH
• kompetitivní chování MeSH
• lidé MeSH
• mladý dospělý MeSH
• srdeční komory diagnostické zobrazování   MeSH
• tělesná námaha fyziologie   MeSH
• tělesná výkonnost fyziologie   MeSH
• ultrasonografie MeSH
• velikost orgánu MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Acidic chitinase (Chia) digests the chitin of insects in the omnivorous stomach and the chitinase activity in carnivorous Chia is significantly lower than that of the omnivorous enzyme. However, mechanistic and evolutionary insights into the functional changes in Chia remain unclear. Here we show that a noninsect-based diet has caused structural and functional changes in Chia during the course of evolution in Carnivora. By creating mouse-dog chimeric Chia proteins and modifying the amino acid sequences, we revealed that F214L and A216G substitutions led to the dog enzyme activation. In 31 Carnivora, Chia was present as a pseudogene with stop codons in the open reading frame (ORF) region. Importantly, the Chia proteins of skunk, meerkat, mongoose, and hyena, which are insect-eating species, showed high chitinolytic activity. The cat Chia pseudogene product was still inactive even after ORF restoration. However, the enzyme was activated by matching the number and position of Cys residues to an active form and by introducing five meerkat Chia residues. Mutations affecting the Chia conformation and activity after pseudogenization have accumulated in the common ancestor of Felidae due to functional constraints. Evolutionary analysis indicates that Chia genes are under relaxed selective constraint in species with noninsect-based diets except for Canidae. These results suggest that there are two types of inactivating processes in Carnivora and that dietary changes affect the structure and activity of Chia.

• Klíčová slova
• Chia, acidic chitinase, carnivores, digestive enzyme, gene loss, insectivores,
• MeSH
• Carnivora * metabolismus   MeSH
• chitin chemie   metabolismus   MeSH
• chitinasy * genetika   metabolismus   MeSH
• dieta MeSH
• myši MeSH
• psi MeSH
• sekvence aminokyselin MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chitin MeSH
• chitinasy * MeSH

OBJECTIVE: Postpartum depression (PPD) is a serious condition with debilitating consequences for the mother, offspring, and the whole family. The scope of negative outcomes of PPD highlights the need to specify effective diagnostics and treatment which might differ from major depressive disorder (MDD). In order to improve our clinical care, we need to better understand the underlying neuropathological mechanisms of PPD. Therefore, we conducted a systematic review of published neuroimaging studies assessing functional, structural, and metabolic correlates of PPD. METHODS: Relevant papers were identified using a search code for English-written studies in the PubMed, Scopus, and Web of Science databases published by March 2022. Included were studies with structural magnetic resonance imaging, functional magnetic resonance imaging, both resting-state and task-related, magnetic resonance spectroscopy, or positron emission tomography. The findings were analyzed to assess signatures in PPD-diagnosed women compared to healthy controls. The review protocol was registered in PROSPERO (CRD42022313794). RESULTS: The total of 3,368 references were initially identified. After the removal of duplicates and non-applicable papers, the search yielded 74 full-text studies assessed for eligibility. Of them, 26 met the inclusion criteria and their findings were analyzed and synthesized. The results showed consistent functional, structural, and metabolic changes in the default mode network and the salient network in women with PPD. During emotion-related tasks, PPD was associated with changes in the corticolimbic system activity, especially the amygdala. DISCUSSION: This review offers a comprehensive summary of neuroimaging signatures in PPD-diagnosed women. It indicates the brain regions and networks which show functional, structural, and metabolic changes. Our findings offer better understanding of the nature of PPD, which clearly copies some features of MDD, while differs in others.

• Klíčová slova
• fMRI, magnetic resonance imaging, magnetic resonance spectroscopy, neuroimaging, perinatal depression, postpartum depression, structural MRI,
• Publikační typ
• časopisecké články MeSH
• systematický přehled MeSH

As phospholipases of Salmonella species may play a role in the pathogenesis of gastrointestinal tract diseases. Salmonella newport, the causative agent of infantile diarrhoea was examined for the production of phospholipase. The enzyme was purified by gel filtration chromatography and was found to be a protein of molar mass ranging from 43 to 67 kDa. The purified enzyme alone or in combination with organisms, produced both structural and functional changes in rabbit ileum, contributing towards pathogenesis of diarrhoea due to this organism.

• MeSH
• fosfolipasy A izolace a purifikace   farmakologie   MeSH
• ileum účinky léků   metabolismus   patologie   MeSH
• králíci MeSH
• průjem etiologie   MeSH
• Salmonella enzymologie   patogenita   MeSH
• salmonelová infekce u zvířat etiologie   MeSH
• tělesné tekutiny účinky léků   metabolismus   MeSH
• virulence MeSH
• vodní a elektrolytová rovnováha účinky léků   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfolipasy A MeSH

Chronic kidney disease (CKD) leads to profound metabolic and hemodynamic changes, which damage other organs, such as heart and brain. The brain abnormalities and cognitive deficit progress with the severity of the CKD and are mostly expressed among hemodialysis patients. They have great socio-economic impact. In this review, we present the current knowledge of involved mechanisms.

• MeSH
• chronická renální insuficience komplikace   patologie   MeSH
• kognitivní poruchy etiologie   patologie   MeSH
• lidé MeSH
• mozek diagnostické zobrazování   patologie   MeSH
• rizikové faktory MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: The known impairments of the cardiovascular system in Parkinson´s disease (PD) are caused by autonomic dysfunction and manifested mainly in postural hypotension, chronotropic insufficiency, and reduced heart rate variability. Other dysfunctions, mainly stress response, arrhythmia occurrence, and heart morphology changes, are still the subject of research. OBJECTIVES: To assess the heart rate and blood pressure reaction during exercise, advanced measurements of heart volumes and mass using cardiac magnetic resonance (CMR), and occurrence of arrhythmias in PD patients. METHODS: Thirty PD patients (19 men, mean age 57.5 years) without known cardiac comorbidities underwent bicycle ergometry, electrocardiogram Holter monitoring and CMR. Exercise and CMR parameters were compared with controls (24 subjects for ergometry, 20 for CMR). RESULTS: PD patients had lower baseline systolic blood pressure (SBP) (117.8 vs. 128.3 mmHg, p < 0.01), peak SBP (155.8 vs. 170.8 mmHg, p < 0.05), and lower heart rate increase (49.7 vs. 64.3 beats per minute, p < 0.01). PD patients had higher indexed left and right ventricular end-diastolic volumes (68.5 vs. 57.3, p = 0.003 and 73.5 vs. 61.0 mL/m2 , respectively) and also indexed left and right ventricular end-systolic volumes (44.1 vs. 39.0, p = 0.013 and 29.0 vs. 22.0 mL/m2 , p = 0.013, respectively). A high prevalence of atrial fibrillation (8 subjects, 26.7%) was found. CONCLUSIONS: This novel study combining functional and structural approaches showed that PD is linked with weaker blood pressure and heart rate reaction during exercise, increased myocardial mass and heart volumes compared to controls, and a high prevalence of atrial fibrillation.

• Klíčová slova
• Parkinson´s disease, arrhythmia, cardiac magnetic resonance, cardiovascular system, symptoms,
• MeSH
• elektrokardiografie MeSH
• fibrilace síní * komplikace   MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• Parkinsonova nemoc * komplikace   epidemiologie   MeSH
• srdce MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Climate change is predicted to drive geographical range shifts that will result in changes in species diversity and functional composition and have potential repercussions for ecosystem functioning. However, the effect of these changes on species composition and functional diversity (FD) remains unclear, especially for mammals, specifically bats. We used species distribution models and a comprehensive ecological and morphometrical trait database to estimate how projected future climate and land-use changes could influence the distribution, composition, and FD of the European bat community. Future bat assemblages were predicted to undergo substantial shifts in geographic range and trait structure. Range suitability decreased substantially in southern Europe and increased in northern latitudes. Our findings highlight the potential for climate change to drive shifts in bat FD, which has implications for ecosystem function and resilience at a continental scale. It is important to incorporate FD in conservation strategies. These efforts should target species with key functional traits predicted to be lost and areas expected to experience losses in FD. Conservation strategies should include habitat and roost protection, enhancing landscape connectivity, and international monitoring to preserve bat populations and their ecosystem services.

Cambios en la composición de la comunidad y la diversidad funcional de murciélagos europeos bajo el cambio climático Resumen Se prevé que el cambio climático provocará desplazamientos geográficos que alterarán la diversidad de las especies y su composición funcional, con posibles repercusiones en el funcionamiento de los ecosistemas. Sin embargo, el efecto de estos cambios sobre la composición de las especies y la diversidad funcional aun no es claro, especialmente en el caso de los mamíferos, en concreto los murciélagos. Utilizamos modelos de distribución de especies y una base de datos integral de rasgos ecológicos y morfométricos para estimar cómo los futuros cambios previstos en el clima y el uso del suelo podrían influir en la distribución, composición y diversidad funcional de la comunidad europea de murciélagos. Se predijo que los futuros conjuntos de murciélagos sufrirían cambios sustanciales en su distribución geográfica y en la estructura de sus atributos. La idoneidad del área de distribución disminuyó sustancialmente en el sur de Europa y aumentó en las latitudes septentrionales. Nuestros resultados ponen de relieve la posibilidad de que el cambio climático provoque cambios en la diversidad funcional de los murciélagos, lo que tiene implicaciones para la función y la resiliencia de los ecosistemas a escala continental. Es importante incorporar la diversidad funcional a las estrategias de conservación. Estos esfuerzos deberían centrarse en las especies con rasgos funcionales clave que se prevé que se pierdan y en las zonas en las que se espera que se produzcan pérdidas de diversidad funcional. Las estrategias de conservación deberían incluir la protección del hábitat y de los dormideros, la mejora de la conectividad del paisaje y el seguimiento internacional para preservar las poblaciones de murciélagos y sus servicios ecosistémicos.

• Klíčová slova
• Cambio global, bats, community composition, composición de la comunidad, composición funcional, functional composition, global change, modelización de la distribución de especies, murciélagos, species distribution modeling,
• MeSH
• biodiverzita * MeSH
• Chiroptera * fyziologie   MeSH
• ekosystém MeSH
• klimatické změny * MeSH
• rozšíření zvířat * MeSH
• zachování přírodních zdrojů * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH

The presence of uranium, with a bulk mass fraction of about 1.5 wt% and radiolytic alterations are a feature of Cenomanian amber from Křižany, at the northeastern edge of the North Bohemian Cretaceous uranium ore district. Pores and microcracks in the amber were filled with a mineral admixture, mainly in the form of Zr-Y-REE enriched uraninite. As a result of radiolytic alterations due to the presence of uranium, structural changes were observed in the Křižany amber in comparison with a reference amber from Nové Strašecí in central Bohemia; this was of similar age and botanical origin but did not contain elevated levels of uranium. Structural changes involved an increase in aromaticity due to dehydroaromatization of aliphatic cyclic hydrocarbons, loss of oxygen functional groups, an increase in the degree of polymerization, crosslinking of CC bonds, formation of a three-dimensional hydrocarbon network in the bulk organic matrix, and carbonization of the organic matrix around the uraninite infill.

• Klíčová slova
• Amber, Fossil resin, Mapping, Micro-FTIR, Radiolytic alteration, SEM/EDX, Uranium,
• MeSH
• jantar chemie   MeSH
• molekulární struktura MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• uran analýza   chemie   MeSH
• zkameněliny MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• jantar MeSH
• uran MeSH

The paper discusses diagnostic possibilities of two-dimensional Doppler echography in ambulatory conditions in evaluating affection of the great arteries in patients with documented lesions of the vascular bed. The application of the given method substantially extends and complements information offered by routine clinical examination, and its informative value approximates that of the invasive examination methods. It makes possible visualization of the carotid, femoral and renal artery, measurement of their diameter, and quantitative assessment of the linear and volume velocity of blood flow. It proved particularly successful in diagnosing stenotic changes on the renal arteries, where it showed high specificity and sensitivity.

• MeSH
• aortitida diagnóza   MeSH
• arteriální okluzní nemoci diagnóza   patologie   MeSH
• arterie patologie   MeSH
• arterioskleróza diagnóza   MeSH
• arteritida diagnóza   MeSH
• dospělí MeSH
• echokardiografie * MeSH
• endarteritida diagnóza   MeSH
• fibromuskulární dysplazie diagnóza   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• reologie MeSH
• rychlost toku krve MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Changes in the chloroplast ultra-structure and photochemical function were studied in detached barley (Hordeum vulgare L. cv. Akcent) leaf segments senescing in darkness or in continuous white light of moderate intensity (90 mumol m-2 s-1) for 5 days. A rate of senescence-induced chlorophyll degradation was similar in the dark- and light-senescing segments. The Chl a/b ratio was almost unchanged in the dark-senescing segments, whereas in the light-senescing segments an increase in this ratio was observed indicating a preferential degradation of light-harvesting complexes of photosystem II. A higher level of thylakoid disorganisation (especially of granal membranes) and a very high lipid peroxidation were observed in the light-senescing segments. In spite of these findings, both the maximal and actual photochemical quantum yields of the photosystem II were highly maintained in comparison with the dark-senescing segments.

• MeSH
• chlorofyl a MeSH
• chlorofyl metabolismus   MeSH
• chloroplasty metabolismus   ultrastruktura   MeSH
• elektronová mikroskopie MeSH
• fotosystém II (proteinový komplex) metabolismus   účinky záření   MeSH
• ječmen (rod) metabolismus   účinky záření   ultrastruktura   MeSH
• listy rostlin metabolismus   účinky záření   ultrastruktura   MeSH
• peroxidace lipidů MeSH
• světlo MeSH
• tma MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chlorofyl a MeSH
• chlorofyl MeSH
• chlorophyll b MeSH Prohlížeč
• fotosystém II (proteinový komplex) MeSH