Zajímavé a srozumitelné informace o lidském těle. Z kolika buněk se skládáme, naše svaly, krevní oběh, nervy, srdce. Něco o dýchání, odpadních látkách. Jak se bránit nemocem a správné návyky. Též o rozmnožování, až po narození miminka. Nechybí slovníček pojmů

Zábavné poučení o anatomii člověka a fungování jeho orgánů. S obrázky, vhodné pro děti do 10 let

• MeSH
• biologie MeSH
• lidské tělo MeSH
• Publikační typ
• populární práce MeSH

• Konspekt
• Literatura pro děti a mládež
• Anatomie člověka a srovnávací anatomie
• NLK Obory
• biologie
• NLK Publikační typ
• literatura pro děti a mládež

Medicago truncatula represents a model plant species for understanding legume-bacteria interactions. M. truncatula roots form a specific root-nodule symbiosis with the nitrogen-fixing bacterium Sinorhizobium meliloti. Symbiotic nitrogen fixation generates high iron (Fe) demands for bacterial nitrogenase holoenzyme and plant leghemoglobin proteins. Leguminous plants acquire Fe via "Strategy I," which includes mechanisms such as rhizosphere acidification and enhanced ferric reductase activity. In the present work, we analyzed the effect of S. meliloti volatile organic compounds (VOCs) on the Fe-uptake mechanisms of M. truncatula seedlings under Fe-deficient and Fe-rich conditions. Axenic cultures showed that both plant and bacterium modified VOC synthesis in the presence of the respective symbiotic partner. Importantly, in both Fe-rich and -deficient experiments, bacterial VOCs increased the generation of plant biomass, rhizosphere acidification, ferric reductase activity, and chlorophyll content in plants. On the basis of our results, we propose that M. truncatula perceives its symbiont through VOC emissions, and in response, increases Fe-uptake mechanisms to facilitate symbiosis.

• MeSH
• biomasa MeSH
• chlorofyl analýza   MeSH
• FMN-reduktasa metabolismus   MeSH
• koncentrace vodíkových iontů MeSH
• kořenové hlízky rostlin mikrobiologie   MeSH
• Medicago truncatula chemie   růst a vývoj   metabolismus   mikrobiologie   MeSH
• půda chemie   MeSH
• Sinorhizobium meliloti metabolismus   MeSH
• těkavé organické sloučeniny metabolismus   MeSH
• železo metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

CD4 and CD8 mark helper and cytotoxic T cell lineages, respectively, and serve as coreceptors for MHC-restricted TCR recognition. How coreceptor expression is matched with TCR specificity is central to understanding CD4/CD8 lineage choice, but visualising coreceptor gene activity in individual selection intermediates has been technically challenging. It therefore remains unclear whether the sequence of coreceptor gene expression in selection intermediates follows a stereotypic pattern, or is responsive to signaling. Here we use single cell RNA sequencing (scRNA-seq) to classify mouse thymocyte selection intermediates by coreceptor gene expression. In the unperturbed thymus, Cd4+Cd8a- selection intermediates appear before Cd4-Cd8a+ selection intermediates, but the timing of these subsets is flexible according to the strength of TCR signals. Our data show that selection intermediates discriminate MHC class prior to the loss of coreceptor expression and suggest a model where signal strength informs the timing of coreceptor gene activity and ultimately CD4/CD8 lineage choice.

• MeSH
• aktivace lymfocytů genetika   MeSH
• analýza hlavních komponent MeSH
• buněčná diferenciace imunologie   MeSH
• buněčný rodokmen imunologie   MeSH
• CD4-pozitivní T-lymfocyty cytologie   imunologie   MeSH
• CD8-pozitivní T-lymfocyty cytologie   imunologie   MeSH
• cytokiny metabolismus   MeSH
• DNA vazebné proteiny metabolismus   MeSH
• histokompatibilní antigeny metabolismus   MeSH
• messenger RNA genetika   metabolismus   MeSH
• myši inbrední C57BL MeSH
• protein PEBP2A3 metabolismus   MeSH
• receptory antigenů T-buněk metabolismus   MeSH
• regulace genové exprese MeSH
• signální transdukce MeSH
• thymus cytologie   imunologie   MeSH
• transkripční faktory metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Halophilic bacterias from saline soil from former Lake Texcoco were isolated, identified based on 16 rRNA and tested to produce glucolytic, nucleolytic, proteolytic and lipolytic exoenzymes. The Bacillus, Virgibacillus, Kocuria, Salinicoccus, Gracilibacillus, Halobacillus, Tenuibacillus and Nesterekonia genera where identified. Lipase/eserases and proteases from Nesterenkonia sp. and Nesterenkonia aethiopica showed halotolerant characteristics and were selected to synthesize the oleochemical n-butyl oleate and antioxidant peptides from muscle protein of common carp (Cyprinus carpio), respectively. In organic media (2,2,4-Trimethylpentane), the lipase/esterases from Nesterenkonia sp. (0.6 U/mL) and N. aethiopica (1.2 U/mL) achieved a 62.7% and 53.2% of n-butyl oleate conversion, respectively. The protein hydrolysis from muscle of common carp (C. carpio) showed a degree of hydrolysis of 4.5 ± 0.2% and 2.8 ± 0.1% when proteases from Nesterenkonia sp. and N. aethiopica were used, respectively. Three peptidic fractions ranging molecular masses between 254 and 1002 Da [M + H] show antioxidant scavenging activity, and the principal fraction with a peptide of 547.3 Da [M + H] showed an inhibition of 37.7 ± 1.8% and 16.3 ± 0.6%, when 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) were used, respectively. These findings showed that the enzymatic battery of the halophilic bacteria from former lake Texcoco can be used in hydrolysis and synthesis of molecules with applications in different fields as food technology or bioenergy.

• MeSH
• antioxidancia chemie   metabolismus   MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• bakteriální proteiny metabolismus   MeSH
• esterasy metabolismus   MeSH
• fylogeneze MeSH
• hydrolýza MeSH
• jezera MeSH
• kapři metabolismus   MeSH
• kyseliny olejové metabolismus   MeSH
• lipasa metabolismus   MeSH
• peptidy chemie   metabolismus   MeSH
• proteasy metabolismus   MeSH
• půdní mikrobiologie MeSH
• RNA ribozomální 16S genetika   MeSH
• tolerance k soli * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Abnormal aggregation of Tau in glial cells has been reported in Alzheimer's disease (AD) and other tauopathies; however, the pathological significance of these aggregates remains unsolved to date. In this study, we evaluated whether full-length Tau (Tau441) and its aspartic acid421-truncated Tau variant (Tau421) produce alterations in the normal organization of the cytoskeleton and plasma membrane (PM) when transiently expressed in cultured C6-glial cells. Forty-eight hours post-transfection, abnormal microtubule bundling was observed in the majority of the cells, which expressed either Tau441 or Tau421. Moreover, both variants of Tau produced extensive PM blebbing associated with cortical redistribution of filamentous actin (F-Actin). These effects were reverted when Tau-expressing cells were incubated with drugs that depolymerize F-Actin. In addition, when glial cells showing Tau-induced PM blebbing were incubated with inhibitors of the Rho-associated protein kinase (ROCK) signaling pathway, both formation of abnormal PM blebs and F-Actin remodeling were avoided. All of these effects were initiated upstream by abnormal Tau-induced microtubule bundling, which may release the microtubule-bound guanine nucleotide exchange factor-H1 (GEF-H1) into the cytoplasm in order to activate its major effector RhoA-GTPase. These results may represent a new mechanism of Tau toxicity in which Tau-induced microtubule bundling produces activation of the Rho-GTPase-ROCK pathway that in turn mediates the remodeling of cortical Actin and PM blebbing. In AD and other tauopathies, these Tau-induced abnormalities may occur and contribute to the impairment of glial activity.

• MeSH
• aktiny účinky léků   metabolismus   MeSH
• buněčná membrána účinky léků   metabolismus   patologie   MeSH
• buněčné linie MeSH
• cytoplazma metabolismus   MeSH
• elektroforéza MeSH
• fluorescenční protilátková technika MeSH
• kinázy asociované s rho metabolismus   MeSH
• koncové značení zlomů DNA in situ MeSH
• konfokální mikroskopie MeSH
• krysa rodu rattus MeSH
• neuroglie účinky léků   metabolismus   patologie   MeSH
• proteiny tau genetika   metabolismus   MeSH
• rhoA protein vázající GTP metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• transfekce MeSH
• tubulin metabolismus   MeSH
• výměnné faktory guaninnukleotidů metabolismus   MeSH
• western blotting MeSH
• zelené fluorescenční proteiny genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. METHODS: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March-June 2019 and 2020. Patients were divided according to age (< or ≥75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. RESULTS: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825-0.861, p < 0.0001). We found a significant age-related reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24-1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05-1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. CONCLUSIONS: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Several reports have demonstrated the impact of the COVID-19 pandemic on the management and outcome of patients with ST-segment elevation myocardial infarction (STEMI). The aim of the current analysis is to investigate the potential gender difference in the effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI patients within the ISACS-STEMI COVID-19 Registry. METHODS: This retrospective multicenter registry was performed in high-volume primary percutaneous coronary intervention (PPCI) centers on four continents and included STEMI patients undergoing PPCIs in March-June 2019 and 2020. Patients were divided according to gender. The main outcomes were the incidence and timing of the PPCI, (ischemia time ≥ 12 h and door-to-balloon ≥ 30 min) and in-hospital or 30-day mortality. RESULTS: We included 16683 STEMI patients undergoing PPCIs in 109 centers. In 2020 during the pandemic, there was a significant reduction in PPCIs compared to 2019 (IRR 0.843 (95% CI: 0.825-0.861, p < 0.0001). We did not find a significant gender difference in the effects of the COVID-19 pandemic on the numbers of STEMI patients, which were similarly reduced from 2019 to 2020 in both groups, or in the mortality rates. Compared to prepandemia, 30-day mortality was significantly higher during the pandemic period among female (12.1% vs. 8.7%; adjusted HR [95% CI] = 1.66 [1.31-2.11], p < 0.001) but not male patients (5.8% vs. 6.7%; adjusted HR [95% CI] = 1.14 [0.96-1.34], p = 0.12). CONCLUSIONS: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures similarly observed in both genders. Furthermore, we observed significantly increased in-hospital and 30-day mortality rates during the pandemic only among females. Trial registration number: NCT 04412655.

• Publikační typ
• časopisecké články MeSH

The so-called "smoking paradox", conditioning lower mortality in smokers among STEMI patients, has seldom been addressed in the settings of modern primary PCI protocols. The ISACS-STEMI COVID-19 is a large-scale retrospective multicenter registry addressing in-hospital mortality, reperfusion, and 30-day mortality among primary PCI patients in the era of the COVID-19 pandemic. Among the 16,083 STEMI patients, 6819 (42.3%) patients were active smokers, 2099 (13.1%) previous smokers, and 7165 (44.6%) non-smokers. Despite the impaired preprocedural recanalization (p < 0.001), active smokers had a significantly better postprocedural TIMI flow compared with non-smokers (p < 0.001); this was confirmed after adjustment for all baseline and procedural confounders, and the propensity score. Active smokers had a significantly lower in-hospital (p < 0.001) and 30-day (p < 0.001) mortality compared with non-smokers and previous smokers; this was confirmed after adjustment for all baseline and procedural confounders, and the propensity score. In conclusion, in our population, active smoking was significantly associated with improved epicardial recanalization and lower in-hospital and 30-day mortality compared with previous and non-smoking history.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is projected to become the third cause of mortality worldwide. COPD shares several pathophysiological mechanisms with cardiovascular disease, especially atherosclerosis. However, no definite answers are available on the prognostic role of COPD in the setting of ST elevation myocardial infarction (STEMI), especially during COVID-19 pandemic, among patients undergoing primary angioplasty, that is therefore the aim of the current study. METHODS: In the ISACS-STEMI COVID-19 registry we included retrospectively patients with STEMI treated with primary percutaneous coronary intervention (PCI) between March and June of 2019 and 2020 from 109 high-volume primary PCI centers in 4 continents. RESULTS: A total of 15,686 patients were included in this analysis. Of them, 810 (5.2%) subjects had a COPD diagnosis. They were more often elderly and with a more pronounced cardiovascular risk profile. No preminent procedural dissimilarities were noticed except for a lower proportion of dual antiplatelet therapy at discharge among COPD patients (98.9% vs. 98.1%, P = 0.038). With regards to short-term fatal outcomes, both in-hospital and 30-days mortality occurred more frequently among COPD patients, similarly in pre-COVID-19 and COVID-19 era. However, after adjustment for main baseline differences, COPD did not result as independent predictor for in-hospital death (adjusted OR [95% CI] = 0.913[0.658-1.266], P = 0.585) nor for 30-days mortality (adjusted OR [95% CI] = 0.850 [0.620-1.164], P = 0.310). No significant differences were detected in terms of SARS-CoV-2 positivity between the two groups. CONCLUSION: This is one of the largest studies investigating characteristics and outcome of COPD patients with STEMI undergoing primary angioplasty, especially during COVID pandemic. COPD was associated with significantly higher rates of in-hospital and 30-days mortality. However, this association disappeared after adjustment for baseline characteristics. Furthermore, COPD did not significantly affect SARS-CoV-2 positivity. TRIAL REGISTRATION NUMBER: NCT04412655 (2nd June 2020).

• MeSH
• chronická obstrukční plicní nemoc * diagnóza   epidemiologie   terapie   MeSH
• COVID-19 * epidemiologie   MeSH
• infarkt myokardu s elevacemi ST úseků * diagnóza   epidemiologie   terapie   MeSH
• koronární angioplastika * škodlivé účinky   MeSH
• lidé MeSH
• mortalita v nemocnicích MeSH
• pandemie MeSH
• registrace MeSH
• retrospektivní studie MeSH
• SARS-CoV-2 MeSH
• senioři MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH

Background: During the coronavirus disease 2019 (COVID-19) pandemic, concerns have been arisen on the use of renin-angiotensin system inhibitors (RASI) due to the potentially increased expression of Angiotensin-converting-enzyme (ACE)2 and patient's susceptibility to SARS-CoV2 infection. Diabetes mellitus have been recognized favoring the coronavirus infection with consequent increase mortality in COVID-19. No data have been so far reported in diabetic patients suffering from ST-elevation myocardial infarction (STEMI), a very high-risk population deserving of RASI treatment. Methods: The ISACS-STEMI COVID-19 registry retrospectively assessed STEMI patients treated with primary percutaneous coronary intervention (PPCI) in March/June 2019 and 2020 in 109 European high-volume primary PCI centers. This subanalysis assessed the prognostic impact of chronic RASI therapy at admission on mortality and SARS-CoV2 infection among diabetic patients. Results: Our population is represented by 3812 diabetic STEMI patients undergoing mechanical reperfusion, 2038 in 2019 and 1774 in 2020. Among 3761 patients with available data on chronic RASI therapy, between those ones with and without treatment there were several differences in baseline characteristics, (similar in both periods) but no difference in the prevalence of SARS-CoV2 infection (1.6% vs 1.3%, respectively, p = 0.786). Considering in-hospital medication, RASI therapy was overall associated with a significantly lower in-hospital mortality (3.3% vs 15.8%, p < 0.0001), consistently both in 2019 and in 2010. Conclusions: This is first study to investigate the impact of RASI therapy on prognosis and SARS-CoV2 infection of diabetic patients experiencing STEMI and undergoing PPCI during the COVID-19 pandemic. Both pre-admission chronic RASI therapy and in-hospital RASI did not negatively affected patients' survival during the hospitalization, neither increased the risk of SARS-CoV2 infection. Trial registration number: NCT04412655.

• Publikační typ
• časopisecké články MeSH