downstream processing
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Despite the efficacy and potential therapeutic benefits that poly(lactic-co-glycolic acid) (PLGA) nanomedicine formulations can offer, challenges related to large-scale processing hamper their clinical and commercial development. Major hurdles for the launch of a polymeric nanocarrier product on the market are batch-to-batch variations and lack of product consistency in scale-up manufacturing. Therefore, a scalable and robust manufacturing technique that allows for the transfer of nanomedicine production from the benchtop to an industrial scale is highly desirable. Downstream processes for purification, concentration, and storage of the nanomedicine formulations are equally indispensable. Here, we develop an inline sonication process for the production of polymeric PLGA nanomedicines at the industrial scale. The process and formulation parameters are optimized to obtain PLGA nanoparticles with a mean diameter of 150 ± 50 nm and a small polydispersity index (PDI < 0.2). Downstream processes based on tangential flow filtration (TFF) technology and lyophilization for the washing, concentration, and storage of formulations are also established and discussed. Using the developed manufacturing and downstream processing technologies, production of two PLGA nanoformulations encasing ritonavir and celecoxib was achieved at 84 g/h rate. As a measure of actual drug content, encapsulation efficiencies of 49.5 ± 3.2% and 80.3 ± 0.9% were achieved for ritonavir and celecoxib, respectively. When operated in-series, inline sonication and TFF can be adapted for fully continuous, industrial-scale processing of PLGA-based nanomedicines.
- Publikační typ
- časopisecké články MeSH
In chronic myeloid leukemia, the identification of individual BCR-ABL1 fusions is required for the development of personalized medicine approach for minimal residual disease monitoring at the DNA level. Next generation sequencing (NGS) of amplicons larger than 1000 bp simplified and accelerated a process of characterization of patient-specific BCR-ABL1 genomic fusions. NGS of large regions upstream and downstream the individual breakpoints in BCR and ABL1 genes, respectively, also provided information about the sequence variants such are single nucleotide polymorphisms.
Cell communication systems based on polypeptide ligands use transmembrane receptors to transmit signals across the plasma membrane. In their biogenesis, receptors depend on the endoplasmic reticulum (ER)-Golgi system for folding, maturation, transport and localization to the cell surface. ER stress, caused by protein overproduction and misfolding, is a well-known pathology in neurodegeneration, cancer and numerous other diseases. How ER stress affects cell communication via transmembrane receptors is largely unknown. In disease models of multiple myeloma, chronic lymphocytic leukemia and osteogenesis imperfecta, we show that ER stress leads to loss of the mature transmembrane receptors FGFR3, ROR1, FGFR1, LRP6, FZD5 and PTH1R at the cell surface, resulting in impaired downstream signaling. This is caused by downregulation of receptor production and increased intracellular retention of immature receptor forms. Reduction of ER stress by treatment of cells with the chemical chaperone tauroursodeoxycholic acid or by expression of the chaperone protein BiP resulted in restoration of receptor maturation and signaling. We show a previously unappreciated pathological effect of ER stress; impaired cellular communication due to altered receptor processing. Our findings have implications for disease mechanisms related to ER stress and are particularly important when receptor-based pharmacological approaches are used for treatment.
- MeSH
- chaperon endoplazmatického retikula BiP MeSH
- kyselina taurochenodeoxycholová farmakologie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- receptory buněčného povrchu * metabolismus MeSH
- signální transdukce * účinky léků MeSH
- stres endoplazmatického retikula * účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Error detection in motor behavior is a fundamental cognitive function heavily relying on local cortical information processing. Neural activity in the high-gamma frequency band (HGB) closely reflects such local cortical processing, but little is known about its role in error processing, particularly in the healthy human brain. Here we characterize the error-related response of the human brain based on data obtained with noninvasive EEG optimized for HGB mapping in 31 healthy subjects (15 females, 16 males), and additional intracranial EEG data from 9 epilepsy patients (4 females, 5 males). Our findings reveal a multiscale picture of the global and local dynamics of error-related HGB activity in the human brain. On the global level as reflected in the noninvasive EEG, the error-related response started with an early component dominated by anterior brain regions, followed by a shift to parietal regions, and a subsequent phase characterized by sustained parietal HGB activity. This phase lasted for more than 1 s after the error onset. On the local level reflected in the intracranial EEG, a cascade of both transient and sustained error-related responses involved an even more extended network, spanning beyond frontal and parietal regions to the insula and the hippocampus. HGB mapping appeared especially well suited to investigate late, sustained components of the error response, possibly linked to downstream functional stages such as error-related learning and behavioral adaptation. Our findings establish the basic spatio-temporal properties of HGB activity as a neural correlate of error processing, complementing traditional error-related potential studies.
- MeSH
- dospělí MeSH
- elektroencefalografie MeSH
- elektrokortikografie MeSH
- gama rytmus EEG fyziologie MeSH
- lidé MeSH
- mapování mozku metody MeSH
- mladý dospělý MeSH
- mozek fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Automatic markerless estimation of infant posture and motion from ordinary videos carries great potential for movement studies "in the wild", facilitating understanding of motor development and massively increasing the chances of early diagnosis of disorders. There has been a rapid development of human pose estimation methods in computer vision, thanks to advances in deep learning and machine learning. However, these methods are trained on datasets that feature adults in different contexts. This work tests and compares seven popular methods (AlphaPose, DeepLabCut/DeeperCut, Detectron2, HRNet, MediaPipe/BlazePose, OpenPose, and ViTPose) on videos of infants in supine position and in more complex settings. Surprisingly, all methods except DeepLabCut and MediaPipe exhibit competitive performance without additional fine-tuning, with ViTPose performing the best. Next to standard performance metrics (average precision and recall), we introduce errors expressed in the neck-mid-hip (torso length) ratio and additionally study missing and redundant detections, and the reliability of the internal confidence ratings of the different methods, which are relevant for downstream tasks. Among the networks with competitive performance, only AlphaPose could run at close to real-time speed (27 fps) on our machine. We provide documented Docker containers or instructions for all the methods we used, our analysis scripts, and the processed data at https://hub.docker.com/u/humanoidsctu and https://osf.io/x465b/ .
- MeSH
- audiovizuální záznam * metody MeSH
- deep learning * MeSH
- kojenec MeSH
- lidé MeSH
- neuronové sítě * MeSH
- počítačové zpracování obrazu * metody MeSH
- postura těla * fyziologie MeSH
- reprodukovatelnost výsledků MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Fuchs endothelial corneal dystrophy (FECD) is a common disease for which corneal transplantation is the only treatment option in advanced stages, and alternative treatment strategies are urgently required. Expansion (≥50 copies) of a non-coding trinucleotide repeat in TCF4 confers >76-fold risk for FECD in our large cohort of affected individuals. An FECD subject-derived corneal endothelial cell (CEC) model was developed to probe disease mechanism and investigate therapeutic approaches. The CEC model demonstrated that the repeat expansion leads to nuclear RNA foci, with the sequestration of splicing factor proteins (MBNL1 and MBNL2) to the foci and altered mRNA processing. Antisense oligonucleotide (ASO) treatment led to a significant reduction in the incidence of nuclear foci, MBNL1 recruitment to the foci, and downstream aberrant splicing events, suggesting functional rescue. This proof-of-concept study highlights the potential of a targeted ASO therapy to treat the accessible and tractable corneal tissue affected by this repeat expansion-mediated disease.
- MeSH
- antisense oligonukleotidy farmakologie MeSH
- buněčné jádro účinky léků metabolismus MeSH
- endoteliální buňky metabolismus MeSH
- expanze trinukleotidových repetic genetika MeSH
- Fuchsova endoteliální dystrofie genetika patologie MeSH
- genetická predispozice k nemoci * MeSH
- kohortové studie MeSH
- lidé MeSH
- messenger RNA metabolismus MeSH
- myši inbrední C57BL MeSH
- orgánová specificita MeSH
- posttranskripční úpravy RNA MeSH
- prekurzory RNA genetika MeSH
- rizikové faktory MeSH
- rohovkový endotel patologie MeSH
- senioři MeSH
- sestřihové faktory metabolismus MeSH
- transkripční faktor 4 genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Nitric oxide (NO) is considered as a signalling molecule involved in a variety of important physiological and pathological processes in plant and animal systems. The major pathway of NO reactions in vivo represents S-nitrosation of thiols to form S-nitrosothiols. S-nitrosoglutathione reductase (GSNOR) is the key enzyme in the degradation pathway of S-nitrosoglutathione (GSNO), a low-molecular weight adduct of NO and glutathione. GSNOR indirectly regulates the level of protein S-nitrosothiol in the cells. This study was focused on the dynamic regulation of the activity of plant GSNORs through reversible S-nitrosation and/or oxidative modifications of target cysteine residues. Pre-incubation with NO/NO- donors or hydrogen peroxide resulted in a decreased reductase and dehydrogenase activity of all studied plant GSNORs. Incubation with thiol reducing agent completely reversed inhibitory effects of nitrosative modifications and partially also oxidative inhibition. In biotin-labelled samples, S-nitrosation of plant GSNORs was confirmed after immunodetection and using mass spectrometry S-nitrosation of conserved Cys271 was identified in tomato GSNOR. Negative regulation of constitutive GSNOR activity in vivo by nitrosative or oxidative modifications might present an important mechanism to control GSNO levels, a critical mediator of the downstream signalling effects of NO, as well as for formaldehyde detoxification in dehydrogenase reaction mode.
- MeSH
- aldehydoxidoreduktasy antagonisté a inhibitory chemie metabolismus MeSH
- cystein chemie metabolismus MeSH
- donory oxidu dusnatého farmakologie MeSH
- nitrosace MeSH
- oxid dusnatý metabolismus MeSH
- oxidace-redukce MeSH
- peroxid vodíku farmakologie MeSH
- posttranslační úpravy proteinů MeSH
- rekombinantní proteiny chemie genetika metabolismus MeSH
- rostlinné proteiny antagonisté a inhibitory chemie metabolismus MeSH
- S-nitrosoglutathion metabolismus MeSH
- S-nitrosothioly metabolismus MeSH
- signální transdukce MeSH
- Solanum lycopersicum genetika růst a vývoj metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Split reporter protein-based genetic section systems are widely used to identify and characterize protein-protein interactions (PPI). The assembly of split markers that antagonize toxins, rather than required for synthesis of missing metabolites, facilitates the seeding of high density of cells and selective growth. Here we present a newly developed split chloramphenicol acetyltransferase (split-CAT) -based genetic selection system. The N terminus fragment of CAT is fused downstream of the protein of interest and the C terminus fragment is tethered upstream to its postulated partner. We demonstrate the system's advantages for the study of PPIs. Moreover, we show that co-expression of a functional ubiquitylation cascade where the target and ubiquitin are tethered to the split-CAT fragments results in ubiquitylation-dependent selective growth. Since proteins do not have to be purified from the bacteria and due to the high sensitivity of the split-CAT reporter, detection of challenging protein cascades and post-translation modifications is enabled. In addition, we demonstrate that the split-CAT system responds to small molecule inhibitors and molecular glues (GLUTACs). The absence of ubiquitylation-dependent degradation and deubiquitylation in E. coli significantly simplify the interpretation of the results. We harnessed the developed system to demonstrate that like NEDD4, UBE3B also undergoes self-ubiquitylation-dependent inactivation. We show that self-ubiquitylation of UBE3B on K665 induces oligomerization and inactivation in yeast and mammalian cells respectively. Finally, we showcase the advantages of split-CAT in the study of human diseases by demonstrating that mutations in UBE3B that cause Kaufman oculocerebrofacial syndrome exhibit clear E. coli growth phenotypes.
- MeSH
- aktivace enzymů MeSH
- biotest metody MeSH
- chloramfenikol-O-acetyltransferasa genetika metabolismus MeSH
- Escherichia coli genetika metabolismus MeSH
- exprese genu * MeSH
- posttranslační úpravy proteinů MeSH
- proteolýza MeSH
- reportérové geny * MeSH
- ubikvitinace * MeSH
- ubikvitinligasy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
... produkci bioléčiv Saccharomyces cerevisae Transgenní zvířata a rostliny Postup výroby léčiv Upstream processing ... ... Downstream processing Hlavní operace Analýza finálních produktů Možné kontaminanty a jejich analýza ...
1. vyd. 148 s. : il., tab. ; 29 cm
Skriptum určené k výuce na VŠCHT Praha.