Normal modes analysis
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Two theories address the origin of repeating patterns, such as hair follicles, limb digits, and intestinal villi, during development. The Turing reaction-diffusion system posits that interacting diffusible signals produced by static cells first define a prepattern that then induces cell rearrangements to produce an anatomical structure. The second theory, that of mesenchymal self-organisation, proposes that mobile cells can form periodic patterns of cell aggregates directly, without reference to any prepattern. Early hair follicle development is characterised by the rapid appearance of periodic arrangements of altered gene expression in the epidermis and prominent clustering of the adjacent dermal mesenchymal cells. We assess the contributions and interplay between reaction-diffusion and mesenchymal self-organisation processes in hair follicle patterning, identifying a network of fibroblast growth factor (FGF), wingless-related integration site (WNT), and bone morphogenetic protein (BMP) signalling interactions capable of spontaneously producing a periodic pattern. Using time-lapse imaging, we find that mesenchymal cell condensation at hair follicles is locally directed by an epidermal prepattern. However, imposing this prepattern's condition of high FGF and low BMP activity across the entire skin reveals a latent dermal capacity to undergo spatially patterned self-organisation in the absence of epithelial direction. This mesenchymal self-organisation relies on restricted transforming growth factor (TGF) β signalling, which serves to drive chemotactic mesenchymal patterning when reaction-diffusion patterning is suppressed, but, in normal conditions, facilitates cell movement to locally prepatterned sources of FGF. This work illustrates a hierarchy of periodic patterning modes operating in organogenesis.
- MeSH
- buněčná diferenciace MeSH
- inbrední kmeny myší MeSH
- kůže cytologie embryologie metabolismus MeSH
- myši MeSH
- rozvržení tělního plánu MeSH
- signální transdukce MeSH
- stanovení celkové genové exprese MeSH
- transformující růstový faktor beta metabolismus fyziologie MeSH
- vlasový folikul embryologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
AIMS: The aim of this project was to define normal values of right ventricular (RV) volumes and ejection fraction (EF) in healthy population using 2D echocardiography. METHODS AND RESULTS: The "patient" group comprised 91 healthy volunteers aged 17-62 years. RV volumetry was based on ellipsoidal shell model method. Left ventricular (LV) volumes were assessed by Teichholz formula. All volumes were indexed per m(2) of BSA and the rate distribution of measured and calculated values were evaluated. The normal range of individual parameters was expressed as mean value+/-2 standard deviations (delta). A pair test was used to compare corresponding results of the RV and LV measurements. The regression analysis was used to test the relationship between LV and RV volumes and age. Indexed enddiastolic and endsystolic RV volumes were 79.1+/-29.9ml and 32.6+/-19.7ml, respectively, EF being 50+/-9.7% in men and 58+/-13.6% in women. No correlation with patient's age was observed. CONCLUSION: Enddiastolic and endsystolic volumes of RV were significantly higher than those of LV. EF of RV was lower as compare to LV. Right ventricular EF in men was lower than that in women. There was no correlation between EF and patient's age.
- MeSH
- dospělí MeSH
- echokardiografie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- normální rozdělení MeSH
- pohlavní dimorfismus MeSH
- regresní analýza MeSH
- srdce - funkce komor MeSH
- srdeční komory ultrastruktura MeSH
- tepový objem fyziologie MeSH
- věkové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
The characterization of differences among polar lipid classes in tumors and surrounding normal tissues of 20 kidney cancer patients is performed by hydrophilic interaction liquid chromatography (HILIC) coupled to electrospray ionization mass spectrometry (ESI-MS). The detailed analysis of identified lipid classes using relative abundances of characteristic ions in negative- and positive-ion modes is used for the determination of more than 120 individual lipid species containing attached fatty acyls of different chain length and double bond number. Lipid species are described using relative abundances, providing a better visualization of lipidomic differences between tumor and normal tissues. The multivariate data analysis methods using unsupervised principal component analysis (PCA) and supervised orthogonal partial least square (OPLS) are used for the characterization of statistically significant differences in identified lipid species. Ten most significant up- and down-regulated lipids in OPLS score plots are also displayed by box plots. A notable increase of relative abundances of lipids containing four and more double bonds is detected in tumor compared to normal tissues.
- MeSH
- glycerofosfolipidy MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací metody MeSH
- hydrofobní a hydrofilní interakce MeSH
- ledviny chemie metabolismus MeSH
- lidé MeSH
- lipidy analýza MeSH
- multivariační analýza MeSH
- nádory ledvin chemie metabolismus MeSH
- výpočetní biologie MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Default mode síť (DMN) je organizovaná síť mozkových oblastí zapojených do mozkové aktivity pozorovatelné v klidovém stavu. Při cíleném provádění experimentální kognitivní úlohy v průběhu vyšetření funkční magnetickou rezonancí (fMR) se tyto oblasti projevují jako tzv. deaktivace. Hlavními oblastmi zapojenými do této sítě jsou ventromediální prefrontální kortex/přední cingulum, zadní cingulum/precuneus a gyrus angularis/lobulus parietalis inferior. Pro sledování DMN u naší skupiny 10 zdravých dobrovolníků jsme použili jednak zobrazení deaktivace ve vztahu k paměťovému úkolu a korelační analýzu (tzv. seed funkční konektivitu) vycházející z oblasti zájmu přestavující cluster zadní cingulum/precuneus, jednak zobrazení pomocí analýzy nezávislých komponent (independent component analysis, ICA). Dále byly provedeny korelace fMR signálu s výkonem ve vizuálním prostorově paměťovém testu a v Addenbrookském kognitivním testu (ACE), konkrétně se subskóry verbální fluence (VFT) a paměť. Zobrazení DMN pomocí seed funkční konektivity významně lépe korelovalo s výsledkem ICA analýzy než s obrazem prosté deaktivace. Dále jsme našli korelaci mezi MR signálem v clusteru zadní cingulum/precuneus a kognitivním výkonem ve VFT.
The default mode network (DMN) is an organized network of brain structures involved in brain activity that may be observed in the resting state. In the course of the performance of an experimental cognitive task during functional MRI examination (fMR), these regions manifest as ?deactivations?. The main areas involved in this network are the ventromedial prefrontal cortex/anterior cingulate cortex, posterior cingulate cortex/precuneus and angular gyrus/inferior parietal cortex. In a group of 10 healthy volunteers we employed the following approaches to the detection of DMN: deactivations related to a visual spatial memory task; seed functional connectivity from the specific region of interest (cluster posterior cingulate cortex/precuneus); and independent component analysis (ICA). We then sought correlations between the MRI signal and the results of the visuo-spatial memory task and the Addenbrook cognitive examination (ACE), in concrete terms with the ACE verbal fluency subscore (VFT), and memory. The ICA approach revealed a higher correlation rate with the results from functional connectivity compared with pure deactivation mapping. We found correlation between MRI signal in the cluster posterior cingulate cortex/precuneus and VFT performance.
Stating the contribution of Doppler ultrasound examination (DU) of prostatic vascularisation towards timely diagnosing prostate cancer. 87 patients with bioptically proven prostate cancer and 10 healthy young men of control group were examined by transrectal ultrasound in B mode, colour flow mapping (CFM) and Doppler frequency analysis. (DFA) The distribution of vessels in prostate is not specific for carcinoma and using CFM, it is impossible to distinguish normal tissue from carcinoma. DU combined with other methods as rectal palpation, PSA, transrectal sonography in B mode may, however, increase carcinoma suspicion, and quicken the indication of considered bioptic puncture.
- MeSH
- adenokarcinom krevní zásobení diagnostické zobrazování MeSH
- dospělí MeSH
- lidé MeSH
- nádory prostaty krevní zásobení diagnostické zobrazování patologie MeSH
- prostata krevní zásobení MeSH
- referenční hodnoty MeSH
- regionální krevní průtok MeSH
- staging nádorů MeSH
- ultrasonografie dopplerovská barevná MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
To gain insight into the prospects for a few-dimensional ab initio quantum-mechanical description of the vibrational motions of conformationally flexible molecular systems, the NH-, NH(2)-, CO- and OH-stretching and COH-bending vibrations of the most stable tryptophan conformations have been probed using simple one- and two-dimensional anharmonic Hamiltonians and potential energy functions evaluated by means of the standard RI-MP2, CCSD(T) and DFT-D quantum chemical procedures. Although strongly dependent on the procedure used, the calculated vibrational spectral patterns have been found to be in a robust one-to-one harmony with their experimental counterparts, thus proving the adequacy of the theory used for the reliable assignment of the experimental data. Therefore, the approach appears to be a suitable tool for assigning the vibrational probing modes even of systems which are too large to be tractable by the standard normal-coordinate analysis.
- MeSH
- kvantová teorie MeSH
- molekulární konformace MeSH
- molekulární modely MeSH
- tryptofan MeSH
- vibrace MeSH
- Publikační typ
- práce podpořená grantem MeSH
INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is increasingly used in cardiac arrest (CA). Adequacy of carotid and coronary blood flows (CaBF, CoBF) and coronary perfusion pressure (CoPP) in ECMO treated CA is not well established. This study compares femoro-femoral (FF) to femoro-subclavian (FS) ECMO and intraaortic balloon counterpulsation (IABP) contribution based on CaBF, CoBF, CoPP, myocardial and brain oxygenation in experimental CA managed by ECMO. METHODS: In 11 female pigs (50.3 ± 3.4 kg), CA was randomly treated by FF versus FS ECMO ± IABP. Animals under general anesthesia had undergone 15 minutes of ventricular fibrillation (VF) with ECMO flow of 5 to 10 mL/kg/min simulating low-flow CA followed by continued VF with ECMO flow of 100 mL/kg/min. CaBF and CoBF were measured by a Doppler flow wire, cerebral and peripheral oxygenation by near infrared spectroscopy. CoPP, myocardial oxygen metabolism and resuscitability were determined. RESULTS: CaBF reached values > 80% of baseline in all regimens. CoBF > 80% was reached only by the FF ECMO, 90.0% (66.1, 98.6). Addition of IABP to FF ECMO decreased CoBF to 60.7% (55.1, 86.2) of baseline, P = 0.004. FS ECMO produced 70.0% (49.1, 113.2) of baseline CoBF, significantly lower than FF, P = 0.039. Addition of IABP to FS did not change the CoBF; however, it provided significantly higher flow, 76.7% (71.9, 111.2) of baseline, compared to FF + IABP, P = 0.026. Both brain and peripheral regional oxygen saturations decreased after induction of CA to 23% (15.0, 32.3) and 34% (23.5, 34.0), respectively, and normalized after ECMO institution. For brain saturations, all regimens reached values exceeding 80% of baseline, none of the comparisons between respective treatment approaches differed significantly. After a decline to 15 mmHg (9.5, 20.8) during CA, CoPP gradually rose with time to 68 mmHg (43.3, 84.0), P = 0 .003, with best recovery on FF ECMO. Resuscitability of the animals was high, both 5 and 60 minutes return of spontaneous circulation occured in eight animals (73%). CONCLUSIONS: In a pig model of CA, both FF and FS ECMO assure adequate brain perfusion and oxygenation. FF ECMO offers better CoBF than FS ECMO. Addition of IABP to FF ECMO worsens CoBF. FF ECMO, more than FS ECMO, increases CoPP over time.
- MeSH
- analýza rozptylu MeSH
- arteriae carotides fyziologie MeSH
- hemodynamika MeSH
- intraaortální balónková pumpa * MeSH
- koronární cévy fyziologie MeSH
- koronární cirkulace fyziologie MeSH
- mimotělní membránová oxygenace metody MeSH
- modely nemocí na zvířatech MeSH
- náhodné rozdělení MeSH
- prasata MeSH
- rychlost toku krve fyziologie MeSH
- srdeční zástava patofyziologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Using immunofluorescence microscopy, we observed that in several established cell culture lines derived from different nonepithelial tissues and species, cells spontaneously emerge, usually at low frequencies, which contain cytoplasmic structures decorated by antibodies specific for cytokeratins 8 and 18. This phenomenon was further examined at both the protein (gel electrophoreses of cytoskeletal proteins, followed by immunoblotting) and the RNA (Northern blots, "nuclear run-on" analysis, in situ hybridization) level. Positive cell lines included simian virus (SV40)-transformed human fibroblasts (HF-SV80, WI-38 VA13), human astrocytic glioma cells (U333 CG/343MG), rat (RVF-SMC) and hamster (BHK-21/13) cells derived from vascular smooth muscle and murine sarcoma MS-180 cells. In two cell lines (HF-SV80 and BHK-21/13), the frequency of the cytokeratin-containing cells and of the cytokeratin fibril arrays per cell was drastically increased upon treatment with 5-azacytidine. The structural appearance of the cytokeratins was variable in the different cell lines but could also differ among cells of the same culture: While small granular or comma-shaped structures or bizarrely shaped filament arrays prevailed in WI-38, RVF and normally grown BHK-21 cells, most of the other lines revealed extended normal-looking, fibrillar arrays. In one line (MS-180), the appearance of cytokeratins was associated with a morphological change, as it was only found in a subpopulation of cells that had lost their typical elongated and spindle-shaped phenotype and assumed a rounded ("coccoid") shape. Our results show that the expression of the genes encoding cytokeratins 8 and 18 is not necessarily restricted to programs of epithelial differentiation and that factors stochastically effective appear in cultured cell lines that allow the synthesis of these cytoskeletal components. Mechanisms possibly involved in this spontaneous and selective advent of cytokeratins 8 and 18 and implications for tumor diagnosis are discussed.
- MeSH
- buněčné linie MeSH
- fibroblasty cytologie metabolismus MeSH
- hladké svalstvo cytologie metabolismus MeSH
- imunohistochemie MeSH
- keratiny genetika metabolismus MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- messenger RNA metabolismus MeSH
- monoklonální protilátky diagnostické užití MeSH
- nádorové buňky kultivované MeSH
- neuroglie cytologie metabolismus MeSH
- regulace genové exprese * MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
