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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
... Introduction 18 -- 4.2 General Principles 19 -- 4.2.1 Chromosome Abnormality Description Rules 20 -- 4.3 Order ... ... of Chromosome Abnormalities 78 -- 6.3.3 Order of Clones 78 -- 6.3.3.1 Cytogenetically Related Clones ... ... 7.3.2 Normal Interphase Signal Pattern 108 -- 7.3.3 Abnormal Interphase Signal Pattern 108 -- 7.3.3.1 Order ... ... Bodies -- 8.3.1 Normal Polar Body Results -- 8.3.2 Abnormal Polar Bodies PB1 -- 8.3.3 Abnormal Aneuploidy ... ... Bodies 138 -- 8.3.1 Normal Polar Body Results 138 -- 8.3.2 Abnormal Polar Bodies PB1 138 -- 8.3.3 Abnormal ...
Genetics
viii, 224 stran : 16 grafických znázornění, ilustrace, 12 tabulek
- Konspekt
- Obecná genetika. Obecná cytogenetika. Evoluce
- NLK Obory
- cytologie, klinická cytologie
- genetika, lékařská genetika
- NLK Publikační typ
- kolektivní monografie
BACKGROUND: Innovations in computer hardware and software capabilities have paved the way for advances in molecular modelling techniques and methods, leading to an unprecedented expansion of their potential applications. In contrast to the docking technique, which usually identifies the most stable selector-selectand (SO-SA) complex for each enantiomer, the molecular dynamics (MD) technique enables the consideration of a distribution of the SO-SA complexes based on their energy profile. This approach provides a more truthful representation of the processes occurring within the column. However, benchmark procedures and focused guidelines for computational treatment of enantioselectivity at the molecular level are still missing. RESULTS: Twenty-eight molecular dynamics simulations were performed to study the enantiorecognition mechanisms of seven N-3,5-dinitrobenzoylated α- and β-amino acids (DNB-AAs), occurring with the two quinine- and quinidine-based (QN-AX and QD-AX) chiral stationary phases (CSPs), under polar-ionic conditions. The MD protocol was optimized in terms of box size, simulation run time, and frame recording frequency. Subsequently, all the trajectories were analyzed by calculating both the type and amount of the interactions engaged by the selectands (SAs) with the two chiral selectors (SOs), as well as the conformational and interaction energy profiles of the formed SA-SO associates. All the MDs were in strict agreement with the experimental enantiomeric elution order and allowed to establish (i) that salt-bridge and H-bond interactions play a pivotal role in the enantiorecognition mechanisms, and (ii) that the π-cation and π-π interactions are the discriminant chemical features between the two SOs in ruling the chiral recognition mechanism. SIGNIFICANCE: The results of this work clearly demonstrate the high contribution given by MD simulations in the comprehension of the enantiorecognition mechanism with Cinchona alkaloid-based CSPs. However, from this research endeavor it clearly emerged that the MD protocol optimization is crucial for the quality of the produced results.
Cíl: V rámci procesu in vitro fertilizace (IVF) zhodnotit možnost použití stavu meiotického vřeténka jako indikátoru zralosti oocytů za účelem optimalizace načasování vitrifikace. Pacienti a metody: V rámci léčby neplodnosti 38leté ženy a 43letého muže metodou IVF-ICSI (intracytoplazmatická injekce spermie) byla zobrazena dělicí vřeténka jako markery zralosti oocytů před jejich vitrifikací z důvodu azoospermie u partnera. Oocyty, u nichž byl úhel mezi polárním tělískem a meiotickým vřeténkem ≤ 30°, případně měly špatně viditelné meiotické vřeténko, byly vitrifikovány 4 hod po vyhodnocení meiotického vřeténka (8 hod po odběru oocytů). Standardně jsou oocyty vitrifikovány 6 hod po odběru oocytů. Výsledky: Delší doba inkubace oocytů pacientky umožnila, aby oocyty před vitrifikací plně dozrály (do fáze MII) a po rozmrazení byly připraveny pro oplodnění. U partnera pacientky byly následně získány vitální spermie po léčbě tamoxifenem, oocyty byly rozmrazeny a oplodněny získanými spermiemi, s následným embryotransferem a porodem zdravého dítěte v termínu. Závěr: Meiotické vřeténko je možné použít jako marker plné zralosti u oocytů před jejich vitrifikací u starších žen. Po rozmrazení byly oocyty zralé a připravené pro oplodnění metodou ICSI.
Aim: Within the in vitro fertilization (IVF) process, to evaluate the possibility of using the state of the meiotic spindle of oocytes as an indicator of maturity in order to optimize the timing of vitrification. Patients and methods: In the presented report, the cause of couple infertility was a combination of a 38-year-old female and 43-year-old male with azoospermia, which was an indication for oocyte vitrification. Oocyte polar bodies and optically birefringent meiotic spindles were visualized by polarized light microscopy and their states and relative positions were used as indicators of oocyte maturation, i.e. readiness for vitrification. Oocytes which had an angle between the polar body and meiotic spindle a ≤ 30° or had a poorly visible meiotic spindle were vitrified 4 hours post-meiotic spindle evaluation (8 hours after ovum pick-up). Results: After thawing, oocytes were fully maturated and prepared for intracytoplasmic sperm injection (ICSI). Following treatment with tamoxifen, vital sperm were retrieved from the patient’s partner, the oocytes were thawed and fertilized with the obtained sperm, with subsequent embryo transfer and delivery of a healthy baby at term. Conclusion: The meiotic spindle can be used as an oocyte maturation pointer in older women. After thawing, the oocytes were fully matured and ready for fertilization by ICSI.
- MeSH
- aparát dělícího vřeténka * ultrastruktura MeSH
- biologické markery * analýza MeSH
- dospělí MeSH
- fertilizace in vitro * metody MeSH
- infertilita terapie MeSH
- lidé MeSH
- oocyty patologie růst a vývoj ultrastruktura MeSH
- polární tělísko MeSH
- tamoxifen terapeutické užití MeSH
- vitrifikace MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
The aim of the study is to investigate the differences in the interaction of three structurally diverse anthocyanidins, namely peonidin, petunidin, and delphinidin, as well as their glucosides with model biological membranes, human albumin, and plasmid DNA in order to look into their structure-activity relationships. Fluorimetric studies, as well as ATR-FTIR analyses, were jointly used in order to determine the changes observed in both the hydrophilic and hydrophobic layers of cell-mimic membranes (MM) which reflected the membrane lipid composition of tumour cells and red blood cell membranes (RBCM). Our results showed that anthocyanins and anthocyanidins can cause an increase in the packing order of the polar heads of lipids, as well as interact with their deeper layers by reducing the fluidity of lipid chains. The results presented here indicate that all compounds tested here possessed the ability to bind to human serum albumin (HSA) and the presence of a glucose molecule within the structures formed by anthocyanidin reduces their ability to bind to proteins. Using fluorescence correlation spectroscopy, it was demonstrated that the compounds tested here were capable of forming stable complexes with plasmid DNA and, particularly, strong DNA conformational changes were observed in the presence of petunidin and corresponding glucoside, as well as delphinidin. The results we obtained can be useful in comprehending the anthocyanins therapeutic action as molecular antioxidants and provide a valuable insight into their mechanism of action.
Experimental and theoretical foundations for femtosecond time-resolved circular dichroism (TRCD) spectroscopy of excitonic systems are presented. In this method, the system is pumped with linearly polarized light and the signal is defined as the difference between the transient absorption spectrum probed with left and with right circularly polarized light. We present a new experimental setup with a polarization grating as key element to generate circularly polarized pulses. Herein the positive (negative) first order of the diffracted light is left-(right-)circularly polarized and serves as a probe pulse in a TRCD experiment. The grating is capable of transferring ultrashort broadband pulses ranging from 470 nm to 720 nm into two separate beams with opposite ellipticity. By applying a specific chopping scheme we can switch between left and right circular polarizations and detect transient absorption (TA) and TRCD spectra on a shot-to-shot basis simultaneously. We perform experiments on a squaraine polymer, investigating excitonic dynamics, and we develop a general theory for TRCD experiments of excitonically coupled systems that we then apply to describe the experimental data in this particular example. At a magic angle of 54.7° between the pump-pulse polarization and the propagation direction of the probe pulse, the TRCD and TA signals become particularly simple to analyze, since the orientational average over random orientations of complexes factorizes into that of the interaction with the pump and the probe pulse, and the intrinsic electric quadrupole contributions to the TRCD signal average to zero for isotropic samples. Application of exciton theory to linear absorption and to linear circular dichroism spectra of squaraine polymers reveals the presence of two fractions of polymer conformations, a dominant helical conformation with close interpigment distances that are suggested to lead to short-range contributions to site energy shifts and excitonic couplings of the squaraine molecules, and a fraction of unfolded random coils. Theory demonstrates that TRCD spectra of selectively excited helices can resolve state populations that are practically invisible in TA spectroscopy due to the small dipole strength of these states. A qualitative interpretation of TRCD and TA spectra in the spectral window investigated experimentally is offered. The 1 ps time component found in these spectra is related to the slow part of exciton relaxation obtained between states of the helix in the low-energy half of the exciton manifold. The dominant 140 ps time constant reflects the decay of excited states to the electronic ground state.
- Publikační typ
- časopisecké články MeSH
In the present work, we characterized in detail strain CM-3-T8T, which was isolated from the rhizosphere soil of strawberries in Beijing, China, in order to elucidate its taxonomic position. Cells of strain CM-3-T8T were Gram-negative, non-spore-forming, aerobic, short rod. Growth occurred at 25-37 °C, pH 5.0-10.0, and in the presence of 0-8% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CM-3-T8T formed a stable clade with Lysobacter soli DCY21T and Lysobacter panacisoli CJ29T, with the 16S rRNA gene sequence similarities of 98.91% and 98.50%. The average nucleotide identity and digital DNA-DNA hybridization values between strain SG-8 T and the two reference type strains listed above were 76.3%, 79.6%, and 34.3%, 27%, respectively. The DNA G + C content was 68.4% (mol/mol). The major cellular fatty acids were comprised of C15:0 iso (36.15%), C17:0 iso (8.40%), and C11:0 iso 3OH (8.28%). The major quinone system was ubiquinone Q-8. The major polar lipids were phosphatidylethanolamine (PE), phosphatidylethanolamine (PME), diphosphatidylglycerol (DPG), and aminophospholipid (APL). On the basis of phenotypic, genotypic, and phylogenetic evidence, strain CM-3-T8T (= ACCC 61714 T = JCM 34576 T) represents a new species within the genus Lysobacter, for which the name Lysobacter changpingensis sp. nov. is proposed.
- MeSH
- DNA bakterií genetika chemie MeSH
- fosfatidylethanolaminy MeSH
- fosfolipidy chemie MeSH
- fylogeneze MeSH
- jahodník * genetika MeSH
- Lysobacter * genetika MeSH
- mastné kyseliny analýza MeSH
- půda MeSH
- rhizosféra MeSH
- RNA ribozomální 16S genetika MeSH
- sekvenční analýza DNA MeSH
- techniky typizace bakterií MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
The aim of this study was to evaluate the efficiency of using meiotic spindle (MS) visibility and relative position to the polar body (PB) as indicators of oocyte maturation in order to optimize intracytoplasmic sperm injection (ICSI) timing. This was a cohort study of patients younger than 40 years with planned ICSI, the timing of which was determined by MS status, compared with those without MS evaluation. The angle between PB and MS and MS visibility were evaluated by optical microscope with polarizing filter. Oocytes with MS evaluation were fertilized according to MS status either 5-6 h after ovum pick-up (OPU) or 7-8 h after OPU. Oocytes without MS evaluation were all fertilized 5-6 h after OPU. For patients over 35 years visualization of MS influenced pregnancy rate (PR): 182 patients with MS visualization had 32% PR (58/182); while 195 patients without MS visualization had 24% PR (47/195). For patients under 35 years, visualization of MS did not influence PR: 140 patients with MS visualization had 41% PR (58/140), while 162 patients without MS visualization had 41% PR (66/162). Visualization of MS therefore appears to be a useful parameter for assessment of oocyte maturity and ICSI timing for patients older than 35.
The aim of this work is to determine the biological activity of ellagitannins rich extracts from leaves of raspberry (Rubus idaeus L.) and wild strawberry (Fragaria vesca L.) in relation to cells and cell membranes. Detailed qualitative and quantitative analysis of phenolic compounds of the extract was made using chromatographic methods. Cytotoxic and antioxidant activities of tested extracts in relation to erythrocytes and human vascular endothelial cells (HMEC-1) were determined by using fluorimetric and spectrophotometric methods. In order to establish the influence of the extracts on the physical properties of the membrane, such as osmotic resistance and erythrocytes shapes, mobility and/or hydration of polar heads and fluidity of hydrocarbon chains of membrane lipids, microscopic and spectroscopic methods were used. The results showed that the extracts are non-toxic for erythrocytes and HMEC-1 cells (up to concentration of 50 μg/mL), but they effectively protect cells and their membranes against oxidative damage. The increase in osmotic resistance of erythrocytes, formation of echinocytes and changes only in the polar part of the membrane caused by the extracts demonstrate their location mainly in the hydrophilic part of the membrane. The results indicate that tested extracts have high biological activities and may be potentially used in delaying the ageing process of organisms and prevention of many diseases, especially those associated with oxidative stress.
- MeSH
- antioxidancia chemie farmakologie MeSH
- endoteliální buňky MeSH
- erytrocyty MeSH
- hydrolyzovatelné taniny MeSH
- jahodník * chemie MeSH
- lidé MeSH
- membránové lipidy MeSH
- oxidační stres MeSH
- rostlinné extrakty chemie farmakologie MeSH
- Rubus * chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This review article introduces the basic principles of infants' neurophysiology, while summarizing the core knowledge of the anatomical structure of the auditory pathway, and presents previous findings on newborns' neural speech processing and suggests their possible applications for clinical practice. In order to tap into the functioning of the auditory pathway in newborns, recent approaches have employed electrophysiological techniques that measure electrical activity of the brain. The neural processing of an incoming auditory stimulus is objectively reflected by means of auditory event-related potentials. The newborn's nervous system processes the incoming sound, and the associated electrical activity of the brain is measured and extracted as components characterized by amplitude, latency, and polarity. Based on the parameters of event-related potentials, it is possible to assess the maturity of a child's brain, or to identify a pathology that needs to be treated or mitigated. For instance, in children with a cochlear implant, auditory event-related potentials are employed to evaluate an outcome of the implantation procedure and to monitor the development of hearing. Event-related potentials turn out to be an irreplaceable part of neurodevelopmental care for high-risk children e.g., preterm babies, children with learning disabilities, autism and many other risk factors.
