Campos, Francisco* Dotaz Zobrazit nápovědu
Hypothermia is an effective neuroprotective strategy for acute stroke. However, in clinical practice, the induction of hypothermia is achieved through the systemic reduction of body temperature (using thermal covers or endovascular cooling devices) which results in a complex system associated in many cases to side effects. Therefore, the aim of this study was to test the magnetocaloric effect as a potential new therapeutic strategy for stroke by means of an adiabatic magnetic refrigerator device. As a first approach, we have developed a simple device to evaluate in vitro the thermodynamic behavior of different concentrations of commercial gadolinium powder as a reference magnetocaloric material. The samples, properly thermally insulated, were cyclically magnetized and demagnetized at room temperature by 1 T permanent magnets in order to induce an adiabatic magnetic effect. Under the experimental conditions tested, results showed a maximun non-accumulative temperature variation of 0.2 °C, insufficient to carry out an effective hypothermia. This study allowed us to discuss about the use of new materials and strategies for further in vivo experiments.
- MeSH
- biokompatibilní materiály MeSH
- cévní mozková příhoda terapie MeSH
- gadolinium MeSH
- magnetické pole MeSH
- magnetismus metody přístrojové vybavení MeSH
- techniky in vitro MeSH
- tepelná vodivost MeSH
- terapeutická hypotermie * metody přístrojové vybavení MeSH
- Publikační typ
- práce podpořená grantem MeSH
OMED terminology for digestive endoscopy ; 34
3a ed. XII, 124 s. : il. ; 24 cm
The oncogenic mutated kinase BRAFV600E is an attractive molecular target because it is expressed in several human cancers, including melanoma. To present, only three BRAF small inhibitors are approved by the FDA for the treatment of patients with metastatic melanoma: Vemurafenib, Dabrafenib and Encorafenib. Although many protocol treatments have been probed in clinical trials, BRAF inhibition has a limited effectiveness because patients invariably develop resistance and secondary toxic effects associated with the therapy. These limitations highlight the importance of designing new and better inhibitors with different structures that could establish different interactions in the active site of the enzyme and therefore decrease resistance progress. Considering the data from our previous report, here we studied two series of derivatives of structural scaffolds as potential BRAF inhibitors: hydroxynaphthalenecarboxamides and substituted piperazinylpropandiols. Our results indicate that structural analogues of substituted piperazinylpropandiols do not show significantly better activities to that previously reported. In contrast, the hydroxynaphthalenecarboxamides derivatives significantly inhibited cell viability and ERK phosphorylation, a measure of BRAF activity, in Lu1205 BRAFV600E melanoma cells. In order to better understand these experimental results, we carried out a molecular modeling study using different combined techniques: docking, MD simulations and quantum theory of atoms in molecules (QTAIM) calculations. Thus, by using this approach we determined that the molecular interactions that stabilize the different molecular complexes are closely related to Vemurafenib, a well-documented BRAF inhibitor. Furthermore, we found that bi-substituted compounds may interact more strongly respect to the mono-substituted analogues, by establishing additional interactions with the DFG-loop at the BRAF-active site. On the bases of these results we synthesized and tested a new series of hydroxynaphthalenecarboxamides bi-substituted. Remarkably, all these compounds displayed significant inhibitory effects on the bioassays performed. Thus, the structural information reported here is important for the design of new BRAFV600E inhibitors possessing this type of structural scaffold.
The identification of the V600E activating mutation in the protein kinase BRAF in around 50% of melanoma patients has driven the development of highly potent small inhibitors (BRAFi) of the mutated protein. To date, Dabrafenib and Vemurafenib, two specific BRAFi, have been clinically approved for the treatment of metastatic melanoma. Unfortunately, after the initial response, tumors become resistant and patients develop a progressive and lethal disease, making imperative the development of new therapeutic options. The main objective of this work was to find new BRAF inhibitors with different structural scaffolds than those of the known inhibitors. Our study was carried out in different stages; in the first step we performed a virtual screening that allowed us to identify potential new inhibitors. In the second step, we synthesized and tested the inhibitory activity of the novel compounds founded. Finally, we conducted a molecular modelling study that allowed us to understand interactions at the molecular level that stabilize the formation of the different molecular complexes. Our theoretical and experimental study allowed the identification of four new structural scaffolds, which could be used as starting structures for the design and development of new inhibitors of BRAF. Our experimental data indicate that the most active compounds reduced significantly ERK½ phosphorylation, a measure of BRAF inhibition, and cell viability. Thus, from our theoretical and experimental results, we propose new substituted hydroxynaphthalenecarboxamides, N-(hetero)aryl-piperazinylhydroxyalkylphenylcarbamates, substituted piperazinylethanols and substituted piperazinylpropandiols as initial structures for the development of new inhibitors for BRAF. Moreover, by performing QTAIM analysis, we are able to describe in detail the molecular interactions that stabilize the different Ligand-Receptor complexes. Such analysis indicates which portion of the different molecules must be changed in order to obtain an increase in the binding affinity of these new ligands.
- MeSH
- antitumorózní látky chemická syntéza metabolismus farmakologie MeSH
- inhibitory proteinkinas chemická syntéza metabolismus farmakologie MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- molekulární struktura MeSH
- nádorové buněčné linie MeSH
- protoonkogenní proteiny B-raf antagonisté a inhibitory metabolismus MeSH
- simulace molekulového dockingu MeSH
- vazba proteinů MeSH
- vemurafenib farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Alpha-1 antitrypsin deficiency (AATD) is a rare disease that is associated with an increased risk of pulmonary emphysema. The European AATD Research Collaboration (EARCO) international registry was founded with the objective of characterising the individuals with AATD and investigating their natural history. METHODS: The EARCO registry is an international, observational and prospective study of individuals with AATD, defined as AAT serum levels < 11 μM and/or proteinase inhibitor genotypes PI*ZZ, PI*SZ and compound heterozygotes or homozygotes of other rare deficient variants. We describe the characteristics of the individuals included from February 2020 to May 2022. RESULTS: A total of 1044 individuals from 15 countries were analysed. The most frequent genotype was PI*ZZ (60.2%), followed by PI*SZ (29.2%). Among PI*ZZ patients, emphysema was the most frequent lung disease (57.2%) followed by COPD (57.2%) and bronchiectasis (22%). Up to 76.4% had concordant values of FEV1(%) and KCO(%). Those with impairment in FEV1(%) alone had more frequently bronchiectasis and asthma and those with impairment in KCO(%) alone had more frequent emphysema and liver disease. Multivariate analysis showed that advanced age, male sex, exacerbations, increased blood platelets and neutrophils, augmentation and lower AAT serum levels were associated with worse FEV1(%). CONCLUSIONS: EARCO has recruited > 1000 individuals with AATD from 15 countries in its first 2 years. Baseline cross sectional data provide relevant information about the clinical phenotypes of the disease, the patterns of functional impairment and factors associated with poor lung function. Trial registration www. CLINICALTRIALS: gov (ID: NCT04180319).
- MeSH
- alfa-1-antitrypsin genetika MeSH
- bronchiektazie * diagnóza epidemiologie MeSH
- chronická obstrukční plicní nemoc * genetika MeSH
- deficit alfa1-antitrypsinu * diagnóza epidemiologie genetika MeSH
- genotyp MeSH
- lidé MeSH
- plicní emfyzém * diagnóza epidemiologie komplikace MeSH
- prospektivní studie MeSH
- průřezové studie MeSH
- registrace MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
- MeSH
- alfa-1-antitrypsin genetika MeSH
- deficit alfa1-antitrypsinu * diagnóza epidemiologie genetika MeSH
- fenotyp MeSH
- lidé MeSH
- registrace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem MeSH
Mexico is one of the most biodiverse countries in the world, with an important proportion of endemism mainly because of the convergence of the Nearctic and Neotropical biogeographic regions, which generate great diversity and species turnover at different spatial scales. However, most of our knowledge of the Mexican ant biota is limited to a few well-studied taxa, and we lack a comprehensive synthesis of ant biodiversity information. For instance, most of the knowledge available in the literature on Mexican ant fauna refers only to species lists by states, or is focused on only a few regions of the country, which prevents the study of several basic and applied aspects of ants, from diversity and distribution to conservation. Our aims in this data paper are therefore (1) to compile all the information available regarding ants across the Mexican territory, and (2) to identify major patterns in the gathered data set and geographic gaps in order to direct future sampling efforts. All records were obtained from raw data, including both unpublished and published information. After exhaustive filtering and updating information and synonyms, we compiled a total of 21,731 records for 887 ant species distributed throughout Mexico from 1894 to 2018. These records were concentrated mainly in the states of Chiapas (n = 6,902, 32.76%) and Veracruz de Ignacio de la Llave (n = 4,329, 19.92%), which together comprise half the records. The subfamily with the highest number of records was Myrmicinae (n = 10,458 records, 48.12%), followed by Formicinae (n = 3,284, 15.11%) and Ponerinae (n = 1,914, 8.8%). Most ant records were collected in the Neotropical region of the country (n = 12,646, 58.19%), followed by the Mexican transition zone (n = 5,237, 24.09%) and the Nearctic region (n = 3,848, 17.72%). Native species comprised 95.46% of the records (n = 20,745). To the best of our knowledge, this is the most complete data set available to date in the literature for the country. We hope that this compilation will encourage researchers to explore different aspects of the population and community research of ants at different spatial scales, and to aid in the establishment of conservation policies and actions. There are no copyright restrictions. Please cite this data paper when using its data for publications or teaching events.
- MeSH
- biodiverzita MeSH
- Formicidae * MeSH
- incidence MeSH
- společenstvo MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Geografické názvy
- Mexiko MeSH
In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
- MeSH
- autofagie * fyziologie MeSH
- autofagozomy MeSH
- biologické markery MeSH
- biotest normy MeSH
- lidé MeSH
- lyzozomy MeSH
- proteiny spojené s autofagií metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- směrnice MeSH