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1.
Planta ; 260(5): 111, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356333

RESUMO

MAIN CONCLUSION: A novel genomic map of the apogamous gametophyte of the fern Dryopteris affinis unlocks oldest hindrance with this complex plant group, to gain insight into evo-devo approaches. The gametophyte of the fern Dryopteris affinis ssp. affinis represents a good model to explore the molecular basis of vegetative and reproductive development, as well as stress responses. Specifically, this fern reproduces asexually by apogamy, a peculiar case of apomixis whereby a sporophyte forms directly from a gametophytic cell without fertilization. Using RNA-sequencing approach, we have previously annotated more than 6000 transcripts. Here, we selected 100 of the inferred proteins homolog to those of Arabidopsis thaliana, which were particularly interesting for a detailed study of their potential functions, protein-protein interactions, and distance trees. As expected, a plethora of proteins associated with gametogenesis and embryogenesis in angiosperms, such as FERONIA (FER) and CHROMATING REMODELING 11 (CHR11) were identified, and more than a dozen candidates potentially involved in apomixis, such as ARGONAUTE family (AGO4, AGO9, and AGO 10), BABY BOOM (BBM), FASCIATED STEM4 (FAS4), FERTILIZATION-INDEPENDENT ENDOSPERM (FIE), and MATERNAL EFFECT EMBRYO ARREST29 (MEE29). In addition, proteins involved in the response to biotic and abiotic stresses were widely represented, as shown by the enrichment of heat-shock proteins. Using the String platform, the interactome revealed that most of the protein-protein interactions were predicted based on experimental, database, and text mining datasets, with MULTICOPY SUPPRESSOR OF IRA4 (MSI4) showing the highest number of interactions: 16. Lastly, some proteins were studied through distance trees by comparing alignments with respect to more distantly or closely related plant groups. This analysis identified DCL4 as the most distant protein to the predicted common ancestor. New genomic information in relation to gametophyte development, including apomictic reproduction, could expand our current vision of evo-devo approaches.


Assuntos
Apomixia , Dryopteris , Perfilação da Expressão Gênica , Células Germinativas Vegetais , Proteínas de Plantas , Células Germinativas Vegetais/metabolismo , Dryopteris/genética , Dryopteris/metabolismo , Apomixia/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas , Filogenia
2.
Rev Esp Enferm Dig ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39267491

RESUMO

Spain is worldwide leader in deceased donation rates per million habitants and count on a strong network of twenty-five liver transplant institutions. Although the access to liver transplantation is higher than in other countries, approximately 10% of patients qualifying for liver transplantation in Spain will die in the waiting list or would be excluded due to clinical deterioration. A robust waiting list prioritization system is paramount to grant the sickest patients with the first positions in the waiting list for an earlier access to transplant. In addition, the allocation policy may not create or perpetuate inequities, particularly in a public and universal healthcare system. Hitherto, Spain lacks a unique national allocation system for elective liver transplantation. Most institutions establish their own rules for liver allocation and only two autonomous regions, namely Andalucía and Cataluña, share part of their waiting list within their territory to provide regional priority to patients requiring more urgent transplantation. This heterogeneity is further aggravated by the recently described sex-based disparities for accessing liver transplantation in Spain, and by the expansion of liver transplant indications, mainly for oncological indications, in absence of clear guidance on the optimal prioritization policy. The present document contains the recommendations from the first consensus of waiting list prioritization for liver transplantation issued by the Spanish Society of Liver Transplantation (SETH). The document was supported by all liver transplant institutions in Spain and by the Organización Nacional de Trasplantes (ONT). Its implementation will allow to homogenize practices and to improve equity and outcomes among patients with end-stage liver disease.

3.
J Extracell Biol ; 3(9): e70004, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39238548

RESUMO

Skeletal growth and fracture healing rely on the mineralization of cartilage in a process called endochondral ossification. Chondrocytes firstly synthesize and then modify cartilage by the release of a wide range of particles into their extracellular space. Extracellular vesicles (EVs) are one type of such particles, but their roles in endochondral ossification are yet to be fully understood. It remains a challenge to obtain representative populations of chondrocyte-derived EVs, owing to difficulties both in preserving the function of primary chondrocytes in culture and in applying the serum-free conditions required for EV production. Here, we used the ATDC5 cell-line to recover chondrocyte-derived EVs from early- and late-differentiation stages, representing chondrocytes before and during cartilage mineralization. After screening different culture conditions, our data indicate that a serum-free Opti-MEM-based culture medium preserves chondrocyte identity and function, matrix mineralization and cell viability. We subsequently scaled-up production and isolated EVs from conditioned medium by size-exclusion chromatography. The obtained chondrocyte-derived EVs had typical ultrastructure and expression of classical EV markers, at quantities suitable for downstream experiments. Importantly, chondrocyte-derived EVs from late-differentiation stages had elevated levels of alkaline phosphatase activity. Hence, we established a method to obtain functional chondrocyte-derived EVs before and during cartilage mineralization that may aid the further understanding of their roles in endochondral bone growth and fracture healing.

4.
J Extra Corpor Technol ; 56(3): 128-135, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39303136

RESUMO

INTRODUCTION: Ventricular assist devices represent a treatment option for patients with advanced heart failure, offering control over various haemodynamic variables. Similarly, the prescription of exercise within a cardiac rehabilitation programme for heart failure patients is recommended to reduce symptoms, and hospitalisations, improve cardiorespiratory fitness, and increase exercise tolerance. Therefore, exercise prescription can impact those with ventricular assist devices. Given the limited evidence on exercise-based cardiac rehabilitation programmes for this population, this review aims to describe the most commonly used strategies and their health benefits when physical exercise is included in a cardiac rehabilitation programme for patients with ventricular assist devices. MATERIALS AND METHODS: An exploratory review was conducted through searches in the databases: PubMed, SCOPUS, PeDro, and ScienceDirect. The search was limited to studies published between 2013 and 2023. Filters were applied independently by title, abstract, and full text. The included articles were analysed based on the description of the types of cardiac rehabilitation strategies used in patients with ventricular assist devices. RESULTS: Seven articles were included. Each programme employed a cardiopulmonary exercise test before prescribing physical exercise. The most commonly used strategy was aerobic exercise, predominantly high-intensity interval training (HIIT) with intensities close to 90% of peak VO2, followed by continuous moderate-intensity exercise. Limb strength exercises were included in three programmes. CONCLUSIONS: The analysed literature suggests that cardiac rehabilitation in patients with ventricular assist devices is safe and can provide benefits in cardiorespiratory fitness and exercise tolerance. High-intensity interval training is identified as an appropriate strategy for achieving results, offering short-term improvements.


Assuntos
Reabilitação Cardíaca , Terapia por Exercício , Insuficiência Cardíaca , Coração Auxiliar , Humanos , Reabilitação Cardíaca/métodos , Terapia por Exercício/métodos , Terapia por Exercício/instrumentação , Insuficiência Cardíaca/reabilitação , Tolerância ao Exercício
5.
Toxics ; 12(9)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39330565

RESUMO

Human precision-cut lung slices (hPCLS) prepared from fibrotic lungs recapitulate the pathophysiological hallmarks of fibrosis. These hallmark features can also be induced by treating non-fibrotic hPCLS with a fibrotic cocktail (FC). As a result, the fibrotic and fibrosis-induced hPCLS are rapidly emerging as preferred models for disease modeling and drug discovery. However, current hPCLS models are limited by tissue viability in culture, as they are usually only viable for one week after harvesting. Here, we demonstrate that the fibrotic hPCLS can be cryopreserved, stored for months, and then thawed on demand without loss of hPCLS viability or protein content for 14 days post-thawing. Cryopreservation also preserves the pro-fibrotic potential of non-fibrotic hPCLS. Specifically, when we treated the thawed non-fibrotic hPCLS with an FC, we observed significant pro-fibrotic cytokine secretion and elevated tissue stiffness. These pro-fibrotic changes were inhibited by the small-molecule tyrosine kinase inhibitor, Nintedanib. Taken together, our work indicates that a feasible solution to prolong the pre-clinical utility of fibrotic and fibrosis-induced hPCLS is cryopreservation. We anticipate that cryopreserved hPCLS will serve as an advantageous predictive model for the evaluation of pro-fibrotic pathways during acute and chronic toxicity testing.

6.
bioRxiv ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39091837

RESUMO

The ketogenic diet, characterized by high fat and low carbohydrates, has gained popularity not only as a strategy for managing body weight but also for its efficacy in delaying cognitive decline associated with neurodegenerative diseases and the aging process. Since this dietary approach stimulates the liver's production of ketone bodies, primarily ß-hydroxybutyrate (BHB), which serves as an alternative energy source for neurons, we investigated whether BHB could mitigate impaired AMPA receptor trafficking, synaptic dysfunction, and cognitive decline induced by metabolic challenges such as saturated fatty acids. Here, we observe that, in cultured primary cortical neurons, exposure to palmitic acid (200µM) decreased surface levels of glutamate GluA1-containing AMPA receptors, whereas unsaturated fatty acids, such as oleic acid and ω-3 docosahexaenoic acid (200µM), and BHB (5mM) increased them. Furthermore, BHB countered the adverse effects of palmitic acid on synaptic GluA1 levels in hippocampal neurons, as well as excitability and plasticity in hippocampal slices. Additionally, daily intragastric administration of BHB (100 mg/kg/day) for two months reversed cognitive impairment induced by a saturated high-fat diet (49% of calories from fat) in a mouse experimental model of obesity. In summary, our findings underscore the significant impact of fatty acids and ketone bodies on AMPA receptors abundance, synaptic function and neuroplasticity, shedding light on the potential use of BHB to delay cognitive impairments associated with metabolic diseases.

7.
Dalton Trans ; 53(36): 15101-15112, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39212934

RESUMO

A library of new neutral and cationic Ni(II) complexes containing isocyanide ligands and mono- or dialkyl-dithiophosphate have been easily prepared and fully characterized. The synthesis of the neutral complexes unfolds through the alkyl transfer from one alkyldithiophosphate leaving group coordinated to the Ni(II) complex. The alkyl transfer is controlled by steric factors and is highly solvent-dependent. These complexes shown to constitute excellent precursors to obtain new families of air stable Ni(II)-based acyclic diaminocarbene complexes (Ni(II)-ADCs) by nucleophilic attack with various alkyl-substituted amines. Remarkably, the ADC is only produced at one of the isocyanide ligands, keeping the other isocyanide unreacted. This was subsequently exploited to prepare the unprecedented neutral and cationic dinuclear Ni(II) complexes containing a bridging bis-carbene ligand using piperazine.

8.
Clin Kidney J ; 17(8): sfae205, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39135937

RESUMO

Anaemia is common in chronic kidney disease (CKD) and has a significant impact on quality of life (QoL), work productivity and outcomes. Current management includes oral or intravenous iron and erythropoiesis-stimulating agents (ESAs), to which hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) have been recently added, increasing the available therapeutic options. In randomised controlled trials, only intravenous iron improved cardiovascular outcome, while some ESAs were associated with increased adverse cardiovascular events. Despite therapeutic advances, several challenges and unmet needs remain in the current management of anaemia of CKD. In particular, clinical practice does not include an assessment of QoL, which prompted a group of European nephrologists and representatives of patient advocacy groups to revisit the current approach. In this consensus document, the authors propose a move towards a more holistic, personalised and long-term approach, based on existing evidence. The focus of treatment should be on improving QoL without increasing the risk of adverse cardiovascular events, and tailoring management strategies to the needs of the individual. In addition, the authors discuss the suitability of a currently available anaemia of CKD-specific health-related QoL measure for inclusion in the routine clinical management of anaemia of CKD. The authors also outline the logistics and challenges of incorporating such a measure into electronic health records and how it may be used to improve QoL for people with anaemia of CKD.

9.
Mol Biochem Parasitol ; 260: 111647, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002760

RESUMO

Entamoeba histolytica, an intestinal parasite of global significance, poses substantial health risks with its associated high morbidity and mortality rates. Despite the current repertoire of molecular tools for the study of gene function in, the regulatory mechanisms governing its pathogenicity remain largely unexplored. This knowledge gap underscores the need to elucidate key genetic determinants orchestrating cellular functions critical to its virulence. Previously, our group generated an avirulent strain, termed UG10, with the same genetic background as the HM1:IMSS strain. UG10 strain, despite showing normal expression levels of well-known virulence factors, was unable to perform in-vitro and in-vivo activities related to amoebic virulence. In this study, we aimed to uncover the genome-wide modifications that rendered the avirulent phenotype of the UG10 strain through whole-genome sequencing. As a complementary approach, we conducted Methylated DNA Immunoprecipitation coupled with sequencing (MeDIP-seq) analysis on both the highly virulent HM1:IMSS strain and the low-virulence UG10 strain to uncover the genome-wide methylation profile. These dual methodologies revealed two aspects of the UG10 avirulent strain. One is the random integration of fragments from the ribosomal gene cluster and tRNA genes, ranging from 120 to 400 bp; and secondly, a clear, enriched methylation profile in the coding and non-coding strand relative to the start codon sequence in genes encoding small GTPases, which is associated with the previously described avirulent phenotype. This study provides the foundation to explore other genetic and epigenetic regulatory circuitries in E. histolytica and novel targets to understand the pathogenic mechanism of this parasite.

10.
Data Brief ; 55: 110597, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38993234

RESUMO

There are several methods for simulating internal combustion engines. The computational fluid dynamics method is the best way to simulate these engines because it can simulate the combustion process, which is a microscopic process. In this study, the simulation of the combustion process in a closed cycle in a diesel engine with a mixture of diesel and hydrogen is done by AVL Fire software. In order to simulate the combustion in the Species and chemical transmission section, a chemkin mechanism is coupled with AVL Fire software. In this study, the effect of 10 % hydrogen fuel and 90 % diesel fuel as well as the effect of nozzle holes (1, 3 and 6 holes) on the engine performance were directly investigated. In order to validate the results of the pressure simulation and the temperature inside the cylinder in the diesel fuel combustion mode, at 2800 rpm and 100 % load, the data were compared with the experimental data. The research also included verification of the heat transfer coefficient (HTC) results with theoretical data obtained by Woschni and Hohenberg. To accurately simulate the combustion process, the simulation data was validated by comparing the pressure and temperature inside the cylinder at a specific operating condition with experimental data. The results indicate that the maximum heat transfer coefficient is achieved at the angle of maximum pressure, with the exhaust valve having the highest coefficient. The addition of hydrogen to diesel fuel results in a 1.72 % increase in the heat transfer coefficient due to increased collisions. In addition, the introduction of hydrogen fuel increases cylinder pressure and engine power, while increasing the number of fuel nozzle holes decreases the coefficient and pressure, which affects fuel penetration and evaporation rate.

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