Equilibration time
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The aim of this study was to determine the effect of Camellia sinensis extract as antioxidant supplement and pre-freezing equilibration times in a soybean lecithin extender for freezing ram semen. In this study, a total of 20 ejaculates were collected from four Ghezel rams and diluted with extenders (1.5% soybean lecithin, 7% glycerol) containing no supplements (control) and Camellia sinensis extract (5, 10, and 15 mg/L) and cryopreserved, immediately after thermal equilibrium was reached at 5 °C (0 h), or 4 h after equilibration. Sperm motility characteristics, membrane integrity, abnormal morphology, mitochondria activity, apoptotic status, MDA and antioxidant activities (GPx, SOD and total antioxidant capacity (TAC)) were evaluated following freeze-thawing. Camellia sinensis extract at level 10 mg/L led to the highest total and progressive motilities percentages, in comparison to other treatments (P < 0.05). Our results showed that Camellia sinensis extract at level of 5 and 10 mg/L led to higher plasma membrane integrity, mitochondria activity and Total antioxidant capacity (TAC) in comparison to the level of 15 mg/L and control group (P < 0.05). Camellia sinensis extract at 10 mg/L level produced the highest percentage of live spermatozoa and the lowest apoptotic spermatozoa in comparison to all treatments (P < 0.05). In addition, level of MDA formation significantly decreased at this concentration, 10 mg/L, compared to all treatments (P < 0.05). No differences (P > 0.05) were observed between equilibration times (0 h vs. 4 h) for sperm samples incubated with or without different concentrations of Camellia sinensis extract. In conclusion, addition of Camellia sinensis extract at level of 10 mg/L can improve post-thawing quality of ram semen cryopreserved in a soybean lecithin extender. However, further research is needed to standardize the process of Camellia sinensis extraction and specially for identifying which compounds are responsible of its beneficial effect on ram sperm cryopreservation.
- MeSH
- antioxidancia farmakologie MeSH
- čaj chemie MeSH
- čajovník čínský MeSH
- glycerol farmakologie MeSH
- Glycine max chemie MeSH
- kryoprezervace metody MeSH
- kryoprotektivní látky farmakologie MeSH
- lecitiny farmakologie MeSH
- motilita spermií účinky léků MeSH
- ovce MeSH
- rostlinné extrakty farmakologie MeSH
- sperma účinky léků MeSH
- spermie účinky léků MeSH
- uchování spermatu metody MeSH
- zmrazování MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Východiska: Nukleosidové analogy představují významnou skupinu léčiv zvaných antimetabolity, využívaných pro léčbu různých typů nádorových onemocnění. Nicméně, efektivita léčby je často limitována vývojem lékové rezistence. Schopnost nádorových buněk přenášet nukleosidy a nukleosidová analoga dovnitř buňky je považována za jeden z významných faktorů ovlivňujících odpověď na léčbu antimetabolity. Vzhledem k hydrofilním vlastnostem antimetabolitů je jejich transport skrze plazmatickou membránu zprostředkováván dvěma strukturně odlišnými skupinami transmembránových proteinů hENT (SLC29) a hCNT (SLC28) zprostředkovávající rovnovážný, resp. koncentrativní nukleosidový transport. Ztráta funkčnosti nukleosidových transportérů byla asociována se snížením efektivity léčby antimetabolity a jejich deriváty u řady různých nádorových onemocnění vč. adenokarcinomu slinivky. Materiál a metody: Efektivita a kinetika inkorporace antimetabolitů byla analyzována na kontrolních a docetaxel-rezistentních modelech nádoru prostaty. Za tímto účelem bylo využito fluorescenčního nukleosidového analogu uridine-furanu a inhibitoru nukleosidových transportérů S-(4-nitrobenzyl) -6-thioinosinu. Pro analýzu byly využity metodické přístupy zahrnující průtokovou cytometrii, konfokální mikroskopii a kvantitativní real-time polymerázovou řetězovou reakci. Výsledky: V této studii jsme s využitím průtokové cytometrie a fluorescenčního nukleosidového analogu, uridine-furanu, aplikovali metodický přístup pro analýzu aktivity nukleosidových transportérů. Zaměřili jsme se na popis dlouhodobé kinetiky a inkorporace uridine-furanu do buňky u kontrolních a chemorezistentních buněčných modelů PC3. Výsledkem naší práce je průkaz asociace aktivity a mRNA exprese nukleosidových transportérů se senzitivitou daných modelů k různým nukleosidovým analogům. Závěr: Fluorescenční techniky mohou sloužit jako verifikovaný a efektivní nástroj k analýze aktivity nukleosidových transportérů, který má potenciál aplikace v klinické onkologii.
Background: Nucleoside analogues represent a relevant class of antimetabolites used for therapy of various types of cancer. However, their effectivity is limited by drug resistance. The nucleoside transport capability of tumour cells is considered to be a determinant of the clinical outcome of treatment regimens using antimetabolites. Due to hydrophilic properties of antimetabolites, their transport across the plasma membrane is mediated by two families of transmembrane proteins, the SLC28 family of cation-linked concentrative nucleoside transporters (hCNTs) and SLC29 family of energy-independent equilibrative nucleoside transporters (hENTs). Loss of functional nucleoside transporters has been associated with reduced efficacy of antimetabolites and their derivatives and treatment failure in diverse malignancies including solid tumours, such as pancreatic adenocarcinoma. Material and Methods: The effectivity and kinetics of antimetabolite uptake were analysed using control and docetaxel-resistant PC3 cells. For this purpose, fluorescent nucleoside analogue probe uridine-furane and inhibitor of nucleoside transporters, S-(4-nitrobenzyl) -6-thioinosine were exploited. Combination of flow cytometry, confocal microscopy and real-time quantitative polymerase chain reaction methodology were used for the analysis. Results: Here we utilized flow cytometric assay for analysis of nucleoside transporters activity employing fluorescent nucleoside analogue, uridine-furane. We have determined the long-time kinetics of uridine-furane incorporation and quantified its levels in the parental prostate cancer cell line PC3 and its chemoresistant derivative. Finally, we have shown an association between the activity and mRNA expression of nucleoside transporters and sensitivity to various nucleoside analogues. Conclusion: Fluorescent techniques can serve as an effective tool for the detection of nucleoside transporter activity which has the potential for application in clinical oncology.
- MeSH
- chemorezistence * MeSH
- docetaxel MeSH
- down regulace MeSH
- konfokální mikroskopie MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- nádory prostaty * genetika patologie MeSH
- nukleosidy MeSH
- proteiny přenášející nukleosidy * metabolismus MeSH
- protinádorové antimetabolity MeSH
- průtoková cytometrie MeSH
- taxoidy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Cílem práce bylo hodnocení výsledků léčby vad Angleovy II.třídy, 1. oddělení u pacientů léčených horním a dolním fixním aparátem s extrakcí dvou horních premolárů. Byly hodnoceny také výsledky léčby 3-8 let po ukoncení aktivní fáze (sejmutí aparátu). Soubor měl 110 pacientů. Výsledky byly hodnoceny na sádrových modelech, zhotovených před léčením (čas T0), po sejmutí aparátu (T1) a v období 3-8 let po ukončení aktivnífáze léčení (T2). Na sádrových modelech bylo hodnoceno: Angleova třída v molárech, vztah ve špičácích, incizální schůdek (OJ), hloubka skusu (OB), délka zubního oblouku, mezišpičáková vzdálenost a velikost stěsnání. Výsledky: po ukončení aktivní fáze léčení (T0-T1) se statisticky významně změnila poloha molárů, špičáků, incizální schůdek hloubka skusu, délka dolního zubního oblouku. V období 3-8 let po sejmutí fixního aparátu (T1-T2) se mírně zvětšila hloubka skusu, mírně se zvětšil incizální schůdek, ale všechny změny byly statisticky nevýznamné.
Treatment results for Angle Class II, Division 1 male lilocclusions are evaluated in patients treated with upper and lower fixed appliance; the therapy involved also extraction of two upper premolars. The treatment results were evaluated also after 3-8 years after the finished active phase (after the removal of fixed appliance). The sample included 110 patients. The results were evaluated in models made prior the commencement of the therapy (time To), after the appliance removal (time T1), and between 3 and 8 years after the active phase ended (time T2). The parameters evaluated were: Angle Class in molars, relationship of canines, overjet (OJ), overbite (OB), length of dental arch, intercanine distance, and the amount of crowding. Results: after the active phase of therapy (To-T1) positions of molars, canines, overjet, overbite, and the length of dental arch changed significantly. In the period of 3-8 years after the appliance was removed (T1T2) only mild increase of overbite and overjet was noticed, however, these changes were statistically insignificant.
Light-harvesting complex II (LHCII) from the marine green macroalga Bryopsis corticulans is spectroscopically characterized to understand the structural and functional changes resulting from adaptation to intertidal environment. LHCII is homologous to its counterpart in land plants but has a different carotenoid and chlorophyll (Chl) composition. This is reflected in the steady-state absorption, fluorescence, linear dichroism, circular dichroism and anisotropic circular dichroism spectra. Time-resolved fluorescence and two-dimensional electronic spectroscopy were used to investigate the consequences of this adaptive change in the pigment composition on the excited-state dynamics. The complex contains additional Chl b spectral forms - absorbing at around 650 nm and 658 nm - and lacks the red-most Chl a forms compared with higher-plant LHCII. Similar to plant LHCII, energy transfer between Chls occurs on timescales from under hundred fs (mainly from Chl b to Chl a) to several picoseconds (mainly between Chl a pools). However, the presence of long-lived, weakly coupled Chl b and Chl a states leads to slower exciton equilibration in LHCII from B. corticulans. The finding demonstrates a trade-off between the enhanced absorption of blue-green light and the excitation migration time. However, the adaptive change does not result in a significant drop in the overall photochemical efficiency of Photosystem II. These results show that LHCII is a robust adaptable system whose spectral properties can be tuned to the environment for optimal light harvesting.
Common carp (Cyprinus carpio) is one of the most cultured fish species over the world with many different breeds and plenty of published protocols for sperm cryopreservation. However, data regarding preservation of gonadal tissue and surrogate production is still missing. A protocol for freezing common carp spermatogonia was developed through varying different factors along a set of serial subsequent experiments. Among the six cryoprotectants tested, the best survival was achieved with dimethyl sulfoxide (Me2SO). In the next experiment, a wide range of cooling rates (0.5-10°C/min) and different concentrations of Me2SO were tested resulting in the highest survival achieved using 2 M Me2SO and cooling rate of -1°C/min. When testing different tissue sizes and incubation times in the cryomedia, the highest viability was observed when incubating 100 mg tissue fragments for 30 min. Finally, sugar supplementation did not yield significant differences. When testing different equilibration (ES) and vitrification solutions (VS) used for needle-immersed vitrification, no significant differences were observed between the tested groups. Additionally, varied exposure time to VS did not improve the vitrification outcome where the viability was 4-fold lower than that of freezing. The functionality of cryopreserved cells was tested by interspecific transplantation into sterilized goldfish recipients. The exogenous origin of the germ cells in gonads of goldfish recipient was confirmed by molecular markers and incorporation rate was over 40% at 3 months post-transplantation. Results of this study can serve for long-term preservation of germplasm in carp which can be recovered in a surrogate recipient.
Byly sledovány změny v poloze zubů od počátečního postavení před léčbou až po polohu zubů po retenční fázi léčby, nejméně 10 let po skončení aktivní ortodontické léčby. Měřená data byla získána ze sádrových modelu 47 pacientů v čase T1, před aktivní léčbou, T2 po aktivní ortodontické léčbě a T3 minimálně 10 let po léčbě. Bylo zjištěno signifikantní zmenšení mezišpičákové vzdálenosti, jakož i zmenšení délky i hloubky dolního zubního oblouku v čase. Stěsnávání frontálního úseku dolního zubního oblouku se v čase vyvíjí.
Changes in the position of teeth from their place before treatment to their position after retention, at least 10 years after the active orthodontic treatment had been measured. The data were obtained from casts of 47 pa tients at time T1 (before active treatment), T2 (after the active orthodontic treatment), and T3 (at least 10 years after the therapy ended). A significant decrease of lower intercanine distance was observed, together with reduction of length and depth of lower dental arch over the time. Crowding in lower anterior teeth is increasing through the time.
A rapid, high-throughput method employing ultra-performance liquid chromatography with tandem quadrupole mass spectrometry (UPLC-MS/MS) was developed and optimized for simultaneous quantification and confirmation of 64 pesticide residues and their toxic metabolites in fruit extracts prepared by a buffered QuEChERS procedure. The total time required for UPLC-MS/MS analysis was 8 min plus 2 min for re-equilibration to the initial UPLC conditions. Performance characteristics were determined for apple extracts spiked at 10 microg kg(-1). The repeatability of measurements expressed as relative standard deviations was in the range 1.5-13% at this level for most analytes. Thanks to very low limits of quantification (<10 microg kg(-1)for the majority of pesticides), an optimized method allows for the reliable control of not only common maximum residue limits (MRLs) set by European Union regulation for various pesticides/fruit combinations, but also of a uniform MRL of 10 microg kg(-1)endorsed for baby food.
- MeSH
- časové faktory MeSH
- Evropská unie MeSH
- financování organizované MeSH
- kalibrace MeSH
- kojenec MeSH
- lidé MeSH
- Malus chemie MeSH
- maximální přípustná koncentrace MeSH
- potrava pro kojence normy MeSH
- referenční standardy MeSH
- reprodukovatelnost výsledků MeSH
- rezidua pesticidů analýza MeSH
- řízení kvality MeSH
- tandemová hmotnostní spektrometrie metody MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- validační studie MeSH
The steady-state operation of Chinese hamster ovary (CHO) cells in perfusion bioreactors requires the equilibration of reactor dynamics and cell metabolism. Accordingly, in this work we investigate the transient cellular response to changes in its environment and their interactions with the bioreactor hydrodynamics. This is done in a benchtop perfusion bioreactor using MALDI-TOF MS through isotope labeling of complex intracellular nucleotides (ATP, UTP) and nucleotide sugars (UDP-Hex, UDP-HexNAc). By switching to a 13 C6 glucose containing feed media during constant operation at 20 × 106 cells and a perfusion rate of 1 reactor volume per day, isotopic steady state was studied. A step change to the 13 C6 glucose medium in spin tubes allowed the determination of characteristic times for the intracellular turnover of unlabeled metabolites pools, τST (≤0.56 days), which were confirmed in the bioreactor. On the other hand, it is shown that the reactor residence time τR (1 day) and characteristic time for glucose uptake τGlc (0.33 days), representative of the bioreactor dynamics, delayed the consumption of 13 C6 glucose in the bioreactor and thus the intracellular 13 C enrichment. The proposed experimental approach allowed the decoupling of bioreactor hydrodynamics and intrinsic dynamics of cell metabolism in response to a change in the cell culture environment. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1630-1639, 2017.
- MeSH
- bioreaktory * MeSH
- buněčné kultury metody MeSH
- CHO buňky MeSH
- Cricetulus MeSH
- glukosa metabolismus MeSH
- hydrodynamika MeSH
- izotopové značení metody MeSH
- křečci praví MeSH
- metabolismus * MeSH
- perfuze MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cílem studie bylo formou dotazníkového šetření zmapovat indikace, celkový zájem a zkušenosti s jednotlivými ortodontickým/ anomáliemi vhodnými k interceptivní léčbě z pohledu praktického zubního lékaře. Do studie bylo zahrnuto 448 dotazníků, které se týkaly konkrétních ortodontických anomálií, vhodné doby jejich odeslání na konzultaci k ortodontistovi, léčebných postupů a možných důsledků v případě zanedbání. Na základě našeho šetření bylo v prevenci a profylaxi ortodontických anomálií ze strany ošetřujících zubních lékařů zjištěno mnoho potěšujících výstupů, ale zároveň i řada nedostatků.
The purpose of the questionnaire survey was to map the indications, overall demand, and experience with individual orthodontic ancomalies suitable for interceptive treatment from the viewpoint of a general dentist. The survey included 448 questionnaires focused on specific orthodontic anomalies, appropriate time of the first consulfation with an orthodontist, therapeutic approaches, and possible consequences due to neglect. Our study brought about a number of satisfying outcomes regarding prevention and prophylaxis of orthodontic anomalies provided by general dentists, however, we also found some deficiencies.
- Klíčová slova
- interceptivní léčba, ortodontické anomálie, spolupráce ortodontisty a pedostomatologa,
- MeSH
- dítě MeSH
- hodnotící studie jako téma MeSH
- lidé MeSH
- ortodoncie korekční * metody využití MeSH
- předškolní dítě MeSH
- statistika jako téma MeSH
- stomatologická péče o děti MeSH
- úprava zubní okluze MeSH
- věkové faktory * MeSH
- vývoj dítěte MeSH
- zuby mléčné abnormality MeSH
- zuby růst a vývoj MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- předškolní dítě MeSH
Hulled, or ancient, wheats were the earliest domesticated wheats by mankind and the ancestors of current wheats. Their cultivation drastically decreased during the 1960s; however, the increasing demand for a healthy and equilibrated diet led to rediscovering these grains. Our aim was to use a non-targeted metabolomic approach to discriminate and characterize similarities and differences between ancient Triticum varieties. For this purpose, 77 hulled wheat samples from three different varieties were collected: Garfagnana T. turgidum var. dicoccum L. (emmer), ID331 T. monococcum L. (einkorn) and Rouquin T. spelta L. (spelt). The ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-QTOF) metabolomics approach highlighted a pronounced sample clustering according to the wheat variety, with an excellent predictability (Q²), for all the models built. Fifteen metabolites were tentatively identified based on accurate masses, isotopic pattern, and product ion spectra. Among these, alkylresorcinols (ARs) were found to be significantly higher in spelt and emmer, showing different homologue composition. Furthermore, phosphatidylcholines (PC) and lysophosphatidylcholines (lysoPC) levels were higher in einkorn variety. The results obtained in this study confirmed the importance of ARs as markers to distinguish between Triticum species and revealed their values as cultivar markers, being not affected by the environmental influences.