The biosynthesis of the lincosamide antibiotics lincomycin A and celesticetin involves the pyridoxal-5'-phosphate (PLP)-dependent enzymes LmbF and CcbF, which are responsible for bifurcation of the biosynthetic pathways. Despite recognizing the same S-glycosyl-L-cysteine structure of the substrates, LmbF catalyses thiol formation through β-elimination, whereas CcbF produces S-acetaldehyde through decarboxylation-coupled oxidative deamination. The structural basis for the diversification mechanism remains largely unexplored. Here we conduct structure-function analyses of LmbF and CcbF. X-ray crystal structures, docking and molecular dynamics simulations reveal that active-site aromatic residues play important roles in controlling the substrate binding mode and the reaction outcome. Furthermore, the reaction selectivity and oxygen-utilization of LmbF and CcbF were rationally engineered through structure- and calculation-based mutagenesis. Thus, the catalytic function of CcbF was switched to that of LmbF, and, remarkably, both LmbF and CcbF variants gained the oxidative-amidation activity to produce an unnatural S-acetamide derivative of lincosamide.

• MeSH
• katalytická doména MeSH
• krystalografie rentgenová MeSH
• linkosamidy * chemie   biosyntéza   metabolismus   MeSH
• pyridoxalfosfát * metabolismus   chemie   MeSH
• simulace molekulární dynamiky MeSH
• simulace molekulového dockingu MeSH
• Publikační typ
• časopisecké články MeSH

The glycoprotein clusterin (CLU) is involved in cell proliferation and DNA damage repair and is highly expressed in tumor cells. Here, we aimed to investigate the effects of CLU dysregulation on two human astrocytic cell lines: CCF-STTG1 astrocytoma cells and SV-40 immortalized normal human astrocytes. We observed that suppression of CLU expression by RNA interference inhibited cell proliferation, triggered the DNA damage response, and resulted in cellular senescence in both cell types tested. To further investigate the underlying mechanism behind these changes, we measured reactive oxygen species, assessed mitochondrial function, and determined selected markers of the senescence-associated secretory phenotype. Our results suggest that CLU deficiency triggers oxidative stress-mediated cellular senescence associated with pronounced alterations in mitochondrial membrane potential, mitochondrial mass, and expression levels of OXPHOS complex I, II, III and IV, indicating mitochondrial dysfunction. This report shows the important role of CLU in cell cycle maintenance in astrocytes. Based on these data, targeting CLU may serve as a potential therapeutic approach valuable for treating gliomas.

• MeSH
• astrocyty * metabolismus   patologie   MeSH
• klusterin * metabolismus   genetika   MeSH
• lidé MeSH
• membránový potenciál mitochondrií * fyziologie   MeSH
• mitochondrie * metabolismus   MeSH
• nádorové buněčné linie MeSH
• oxidační stres fyziologie   MeSH
• oxidativní fosforylace MeSH
• poškození DNA MeSH
• proliferace buněk * MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• stárnutí buněk * fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

AIM: To assess the feasibility, safety and efficacy of using a high-flow nasal cannula (HFNC) for stabilising very preterm infants after birth. METHODS: A prospective observational study included preterm infants born at 28 + 0 to 31 + 6 weeks' gestation between February 2021 and December 2022 at the General University Hospital in Prague. Following delayed cord clamping, HFNC was administered at a flow rate of 8 L/min through the infants' nostrils. Criteria for switching to continuous positive airway pressure (CPAP) or positive pressure ventilation (PPV) included persistent bradycardia in the first few minutes or low saturation of oxygen (SpO2) after 5 min, respectively. RESULTS: Of the 65 infants enrolled in the study, 56 (86%) were successfully stabilised exclusively using HFNC while 7 (11%) required PPV. Additionally, 52 (80%) infants achieved SpO2 > 80% at 5 min, and 54 (83%) infants were successfully treated with HFNC within the first 3 h of life. CONCLUSION: The primary use of HFNC seems to be an appropriate alternative to CPAP for the stabilisation of very premature infants after birth and subsequent transfer to the NICU. A randomised trial comparing HFNC and CPAP in the delivery room will enable to answer the questions raised in this study.

• MeSH
• kanyla * MeSH
• lidé MeSH
• novorozenci extrémně nezralí * MeSH
• novorozenec nedonošený MeSH
• novorozenec MeSH
• oxygenoterapie * přístrojové vybavení   metody   MeSH
• prospektivní studie MeSH
• studie proveditelnosti MeSH
• trvalý přetlak v dýchacích cestách MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH

Chronická obštrukčná choroba pľúc (CHOCHP) je jedno z najzávažnejších chronických respiračných ochorení, charakterizované vysokou morbiditou a mortalitou. Akútne exacerbácie CHOCHP sú hlavnou príčinou hospitalizácií týchto pacientov a vedú k progresívnemu zhoršovaniu pľúcnych funkcií. Manažment exacerbácií CHOCHP zahŕňa farmakologické a nefarmakologické postupy, pričom neinvazívna ventilácia (NIV) je základnou metódou liečby hyperkapnického respiračného zlyhávania. Vysokoprietoková nazálna oxygenoterapia (HFNO) predstavuje inovatívnu formu respiračnej podpory, ktorá sa postupne dostáva do klinickej praxe a odporúčaní manažmentu akútneho respiračného zlyhávania (I. a II. typu). HFNO dodáva ohriatu zmes plynov pri vysokej prietokovej rýchlosti (až 60 l/min), čím zabezpečuje stabilnú oxygenáciu, vymývanie mŕtveho priestoru a vytvára pozitívny pretlak v dýchacích cestách (3-5 cm H2O). Aktuálne vedecké dôkazy naznačujú, že HFNO môže zlepšiť oxygenáciu, znižovať dychovú prácu a zvýšiť komfort pacientov s akútnou exacerbáciou CHOCHP v porovnaní s NIV, resp. konvenčnou kyslíkovou liečbou. Súčasné odporúčania Európskej respiračnej spoločnosti navrhujú možnosť uprednostniť použitie HFNO u pacientov s hypoxemickým respiračným zlyhávaním bez hyperkapnie oproti použitiu štandardnej oxygenoterapie. Taktiež odporúčajú uprednostniť použitie HFNO v prestávkach ventilácie u pacientov liečených NIV oproti použitiu štandardnej oxygenoterapie. Cieľom predkladanej práce je poskytnúť prehľad súčasných poznatkov o mechanizmoch priaznivého účinku HFNO a o možnostiach použitia tejto liečby pri exacerbáciách CHOCHP spojených s akútnym respiračným zlyhávaním. Súčasťou príspevku je aj kazuistika pacienta s akútnou exacerbáciou CHOCHP, u ktorého bola v manažmente závažného hypoxického respiračného zlyhávania úspešne použitá liečba HFNO.

BACKGROUND: In refractory cardiac arrest, extracorporeal cardiopulmonary resuscitation may increase the survival chance. However, in cases of unsuccessful treatment, extracorporeal cardiopulmonary resuscitation may additionally provide an important source of organ donors. Therefore, we hypothesized that implementing extracorporeal cardiopulmonary resuscitation service into a high-volume cardiac arrest center's routine would increases organ donors' availability. METHODS: Our retrospective observational study analyzed out-of-hospital cardiac arrest patients admitted to the General University Hospital in Prague between 2007 and 2020. The following groups were analyzed regarding the recruitment of donors: before and after extracorporeal cardiopulmonary resuscitation implementation. We assessed the number of donors referred, the number of organs harvested, and the organ's survival. RESULTS: We analyzed the results of 1,158 patients after out-of-hospital cardiac arrest. In the conventional approach period, 11 donors were referred, of which 7 were accepted. During the extracorporeal cardiopulmonary resuscitation period, the number of donors increased to 80, of whom 42 were accepted. The number of donated organs was 18 and 119 in the respective periods, corresponding to 3.6 vs 13.2 (p = 0.033) harvested organs per year. One-year survival of transplanted organs was 94.4% vs 99.2%, and 5-year survival was 94.4% vs 95.9% in relevant periods. Conventional and extracorporeal cardiopulmonary resuscitation did not affect donor organ survival. CONCLUSION: Establishing a high-volume cardiac arrest center providing an extracorporeal cardiopulmonary resuscitation service may increase not only the number of prolonged cardiac arrest survivors but also the number of organ donors. In addition, the performances of donated organs were high and comparable between both treatment methods.

• MeSH
• dárci tkání * zásobování a distribuce   MeSH
• dospělí MeSH
• kardiopulmonální resuscitace * metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mimotělní membránová oxygenace * metody   MeSH
• retrospektivní studie MeSH
• senioři MeSH
• zástava srdce mimo nemocnici * terapie   MeSH
• získávání tkání a orgánů * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH

Úvod: Plicní sekvestrace je vzácná vrozená anomálie dolních dýchacích cest, která je většinou diagnostikována už v dětském věku. Jde o plicní parenchym, který má anomální nebo chybějící komunikaci s tracheobronchiálním stromem. Cévní zásobení není napojeno na plicní oběh, ale pochází ze systémového oběhu. Intralobární plicní sekvestrací se rozumí plicní sekvestr, který má společnou pleuru s normálním parenchymem. Naopak extralobární sekvestr má svou vlastní viscerální pleuru, která nesouvisí s normální plící. Extralobární sekvestrace na rozdíl od intralobární většinou nemá infekční projevy, protože chybí napojení na tracheobronchiální strom. Naopak se může projevit hypoxií, kardiálním selháním či vzácně torzí sekvestru. Častěji však jde o náhodný asymptomatický nález. Vedoucí úlohu v diagnostice má v současnosti CT, které umožňuje zobrazení přívodných cév. Metodou léčby je chirurgická resekce, hlavně jako prevence krvácení či maligního zvratu tkáně. Resekce také poskytne materiál pro bioptické vyšetření. Kazuistika: 68letá pacientka s nefropatií byla v režii nefrologa indikována k ultrasonografii břicha, kde byl náhodně zjištěn tumor v retroperitoneu vlevo. Bylo doplněno CT vyšetření a poté byla indikována k exstirpaci tumoru pro podezření na neurogenní tumor, avšak histologicky šlo o extralobární plicní sekvestraci. Další průběh pak nebyl nijak komplikován. Propuštěna do domácí péče byla 5. pooperační den. Závěr: Kazuistikou chceme prezentovat velmi raritní diagnózu, která je o to vzácnější, že byla nalezena u dospělé pacientky.

Introduction: Pulmonary sequestration is a rare congenital anomaly of the lower respiratory tract, usually diagnosed in childhood. It involves lung parenchyma that has abnormal or absent communication with the tracheobronchial tree. The blood supply is not connected to the pulmonary circulation but comes from the systemic circulation. Intralobar pulmonary sequestration refers to pulmonary sequestration that shares a common pleura with normal parenchyma. In contrast, extralobar sequestration has its own visceral pleura that is not continuous with the normal lung. Extralobar pulmonary sequestration, unlike intralobar pulmonary sequestration, typically does not present with infectious manifestations due to the absence of a connection to the tracheobronchial tree. Instead, it may manifest as hypoxia, cardiac failure, or rarely, torsion of the sequestrum. However, it is more often an incidental asymptomatic finding. Computed tomography currently plays a leading role in diagnosis, enabling visualization of the feeding vessels. Surgical resection is the mainstay of the treatment, primarily to prevent hemorrhage or malignant transformation of the tissue. Resection also provides material for biopsy examination. Case report: A 68-year-old patient with nephropathy was referred by her nephrologist for abdominal ultrasound, which incidentally detected a tumor in the left retroperitoneum. A CT scan was performed, and the patient was then referred for tumor excision due to suspicion of a neurogenic tumor. Postoperatively, she was monitored in the intensive care unit with oxygen therapy for hypoxemia. The further course was uncomplicated. She was discharged home on postoperative day 5. Conclusion: We present a case of this very rare diagnosis, which is even rarer in an adult patient.

• MeSH
• abnormality dýchací soustavy chirurgie   diagnostické zobrazování   MeSH
• bronchopulmonální sekvestrace * chirurgie   diagnostické zobrazování   MeSH
• lidé MeSH
• retroperitoneální nádory * chirurgie   diagnostické zobrazování   MeSH
• senioři MeSH
• vrozené vady MeSH
• vzácné nemoci MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH
• práce podpořená grantem MeSH

Twenty-eight endurance-trained males aged 31.1 ± 10.2 years (body mass [BM] 81.9 ± 9.0 kg) completed this randomized double-blind placebo (PLA)-controlled crossover study investigating the effect of 12-week Colostrum Bovinum (COL) supplementation (25gCOL·day-1) on aerobic fitness and capacity, time to exhaustion, BM and body composition (BC), and blood lactate concentration. There were four main-before/after supplementation study visits (COLPRE and COLPOST; PLAPRE, and PLAPOST). During study visits, BM and BC evaluation, incremental rowing test (IRT) to exhaustion, and evaluation of resting (REST) and post-exercise (POST-IRT) blood lactate concentration were performed. COL, but not PLA supplementation, significantly increased (p < 0.05) time to ventilatory threshold (TVT). Moreover, the implemented treatments had large (mL·min-1) and moderate (mL·min-1·kg-1) effects on oxygen uptake at VT (VO2VT), as well as moderate effect on power output at VT (PVT; W·kg-1) with the highest values observed at COLPOST visit. Neither significant influence of COL supplementation on time to exhaustion (TEXH) in IRT, BM, and BC on blood lactate was observed. Importantly, there were significantly (p < 0.05) higher increases in VO2VT (mL·min-1 and mL·min-1·kg-1) after COL compared to PLA supplementation. In summary, COL supplementation resulted in a favorable increase in TVT, and tended to improve some of the evaluated threshold indicators, namely VO2VT and PVT in endurance-trained male athletes during IRT. Therefore, COL supplementation may be considered as a support to improve aerobic fitness and capacity in endurance-trained males; however, supplementation strategy must be personalized and properly incorporated into the individual training. TRIAL REGISTRATION: The study protocol was registered at ClinicalTrials.gov (NCT06390670).

• MeSH
• dospělí MeSH
• dvojitá slepá metoda MeSH
• fyzická vytrvalost * MeSH
• klinické křížové studie MeSH
• kolostrum * MeSH
• kyselina mléčná krev   MeSH
• lidé MeSH
• mladý dospělý MeSH
• potravní doplňky * MeSH
• složení těla * MeSH
• spotřeba kyslíku MeSH
• vytrvalostní trénink * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

BACKGROUND & AIMS: Despite strong evidence for improved preservation of donor livers by machine perfusion, longer post-transplant follow-up data are urgently needed in an unselected patient population. We aimed to assess long-term outcomes after transplantation of hypothermic oxygenated machine perfusion (HOPE)-treated donor livers based on real-world data (i.e., IDEAL-D stage 4). METHODS: In this international, multicentre, observational cohort study, we collected data from adult recipients of HOPE-treated livers transplanted between January 2012 and December 2021. Analyses were stratified by donation after brain death (DBD) and donation after circulatory death (DCD), sub-divided by their respective risk categories. The primary outcome was death-censored graft survival. Secondary outcomes included the incidence of primary non-function (PNF) and ischaemic cholangiopathy (IC). RESULTS: We report on 1,202 liver transplantations (64% DBD) performed at 22 European centres. For DBD, a total number of 99 benchmark (8%), 176 standard (15%), and 493 extended-criteria (41%) cases were included. For DCD, 117 transplants were classified as low risk (10%), 186 as high risk (16%), and 131 as futile (11%), with significant risk profile variations among centres. Actuarial 1-, 3-, and 5-year death-censored graft survival rates for DBD and DCD livers were 95%, 92%, and 91%, vs. 92%, 87%, and 81%, respectively (log-rank p = 0.003). Within DBD and DCD strata, death-censored graft survival was similar among risk groups (log-rank p = 0.26, p = 0.99). Graft loss due to PNF or IC was 2.3% and 0.4% (DBD), and 5% and 4.1% (DCD). CONCLUSIONS: This study shows excellent 5-year survival after transplantation of HOPE-treated DBD and DCD livers with low rates of graft loss due to PNF or IC, irrespective of their individual risk profile. HOPE treatment has now reached IDEAL-D stage 4, which further supports its implementation in routine clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05520320. IMPACT AND IMPLICATIONS: This study demonstrates the excellent long-term performance of hypothermic oxygenated machine perfusion (HOPE) treatment of donation after circulatory and donation after brain death liver grafts irrespective of their individual risk profile in a real-world setting, outside the evaluation of randomised-controlled trials. While previous studies have established safety, feasibility, and efficacy against the current standard, according to the IDEAL-D evaluation framework, HOPE treatment has now reached the final IDEAL-D stage 4, which further supports its implementation in routine clinical practice.

• MeSH
• dárci tkání statistika a číselné údaje   MeSH
• dospělí MeSH
• kohortové studie MeSH
• lidé středního věku MeSH
• lidé MeSH
• perfuze * metody   přístrojové vybavení   MeSH
• přežívání štěpu * MeSH
• senioři MeSH
• terapeutická hypotermie metody   MeSH
• transplantace jater * metody   škodlivé účinky   MeSH
• uchovávání orgánů * metody   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH

Many photosensitive substances suitable for photodynamic therapy (PDT) have limited applications due to their insufficient solubility in polar solvents. Our research overcomes this challenge by means of nanotechnology in order to transform hydrophobic compounds into stable aqueous solutions, enabling them to use their full potential and unique properties in cancer therapy. In this study, the novel nano-composite cGQDs-PEG-curcumin was developed to overcome the insolubility of curcumin in water and its extraordinary efficacy in PDT was evaluated. Complex characterization was performed using high-resolution transmission electron microscopy (HR-TEM), FTIR, and UV-Vis spectroscopy. Further analysis involved fluorescence lifetime imaging (FLIM), and its cellular localization was mapped with confocal microscopy. In order to evaluate PDT effectiveness, cells treated with cGQDs-PEG-curcumin were irradiated with 5 J/cm2 of 414 nm light. After irradiation, cell viability assay, scanning electron microscopy (SEM), reactive oxygen species (ROS) detection, comet assay, and γH2AX-based DNA double-strand breaks (DSBs) detection were assessed and revealed a remarkable ability of the nano-composite to induce DNA damage after irradiation without ROS production. Our findings highlight the potential of cGQDs-PEG-curcumin as a cutting-edge PDT agent, capable of disrupting cell membrane and nucleolar integrity and impairing ribosomal synthesis, which is crucial for proliferating tumour cells.

• MeSH
• buněčné jadérko * účinky léků   metabolismus   MeSH
• dvouřetězcové zlomy DNA účinky léků   MeSH
• fotochemoterapie * metody   MeSH
• fotosenzibilizující látky * farmakologie   MeSH
• grafit * chemie   farmakologie   MeSH
• kurkumin * farmakologie   chemie   MeSH
• kvantové tečky * chemie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádory * farmakoterapie   MeSH
• polyethylenglykoly * chemie   farmakologie   MeSH
• poškození DNA * účinky léků   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Cardiovascular diseases are associated with an altered cardiomyocyte metabolism. Because of a shortage of human heart tissue, experimental studies mostly rely on alternative approaches including animal and cell culture models. Since the use of isolated primary cardiomyocytes is limited, immortalized cardiomyocyte cell lines may represent a useful tool as they closely mimic human cardiomyocytes. This study is focused on the AC16 cell line generated from adult human ventricular cardiomyocytes. Despite an increasing number of studies employing AC16 cells, a comprehensive proteomic, bioenergetic, and oxygen-sensing characterization of proliferating vs. differentiated cells is still lacking. Here, we provide a comparison of these two stages, particularly emphasizing cell metabolism, mitochondrial function, and hypoxic signaling. Label-free quantitative mass spectrometry revealed a decrease in autophagy and cytoplasmic translation in differentiated AC16, confirming their phenotype. Cell differentiation led to global increase in mitochondrial proteins [e.g. oxidative phosphorylation (OXPHOS) proteins, TFAM, VWA8] reflected by elevated mitochondrial respiration. Fatty acid oxidation proteins were increased in differentiated cells, whereas the expression levels of proteins associated with fatty acid synthesis were unchanged and glycolytic proteins were decreased. There was a profound difference between proliferating and differentiated cells in their response to hypoxia and anoxia-reoxygenation. We conclude that AC16 differentiation leads to proteomic and metabolic shifts and altered cell response to oxygen deprivation. This underscores the requirement for proper selection of the particular differentiation state during experimental planning.NEW & NOTEWORTHY Proliferating and differentiated AC16 cell lines exhibit distinct proteomic and metabolic profiles with critical implications for experimental design. Proliferating cells predominantly utilize glycolysis and are highly sensitive to hypoxia, whereas differentiated cells display enhanced mitochondrial biogenesis, oxidative phosphorylation, and resistance to anoxia-reoxygenation. These findings provide novel insights into the metabolic adaptations during differentiation and highlight the necessity of selecting the appropriate cellular stage to ensure accurate experimental outcomes.

• MeSH
• buněčná diferenciace * fyziologie   MeSH
• buněčné linie MeSH
• energetický metabolismus MeSH
• hypoxie buňky fyziologie   MeSH
• kardiomyocyty * metabolismus   MeSH
• lidé MeSH
• mitochondriální proteiny metabolismus   MeSH
• mitochondrie * metabolismus   MeSH
• oxidativní fosforylace MeSH
• proliferace buněk MeSH
• proteomika metody   MeSH
• signální transdukce * fyziologie   MeSH
• srdeční mitochondrie * metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH