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1.
Nat Immunol ; 17(5): 514-522, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27043414

RESUMO

Cytosolic DNA-mediated activation of the transcription factor IRF3 is a key event in host antiviral responses. Here we found that infection with DNA viruses induced interaction of the metabolic checkpoint kinase mTOR downstream effector and kinase S6K1 and the signaling adaptor STING in a manner dependent on the DNA sensor cGAS. We further demonstrated that the kinase domain, but not the kinase function, of S6K1 was required for the S6K1-STING interaction and that the TBK1 critically promoted this process. The formation of a tripartite S6K1-STING-TBK1 complex was necessary for the activation of IRF3, and disruption of this signaling axis impaired the early-phase expression of IRF3 target genes and the induction of T cell responses and mucosal antiviral immunity. Thus, our results have uncovered a fundamental regulatory mechanism for the activation of IRF3 in the cytosolic DNA pathway.


Assuntos
DNA/imunologia , Fator Regulador 3 de Interferon/imunologia , Proteínas de Membrana/imunologia , Proteínas Quinases S6 Ribossômicas 90-kDa/imunologia , Adenoviridae/genética , Adenoviridae/imunologia , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Citosol/imunologia , Citosol/metabolismo , Citosol/virologia , DNA/genética , DNA/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células HEK293 , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/fisiologia , Humanos , Imunização/métodos , Immunoblotting , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Nucleotidiltransferases/metabolismo , Ovalbumina/genética , Ovalbumina/imunologia , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo
2.
J Comput Chem ; 45(12): 863-877, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38153839

RESUMO

This work provides a detailed multi-component analysis of aromaticity in monosubstituted (X = CH3, C H 2 - , C H 2 + , NH2, NH-, NH+, OH, O-, and O+) and para-homodisubstituted (X = CH3, CH2, NH2, NH, OH, and O) benzene derivatives. We investigate the effects of substituents using single-reference (B3LYP/DFT) and multireference (CASSCF/MRCI) methods, focusing on structural (HOMA), vibrational (AI(vib)), topological (ELFπ), electronic (MCI), magnetic (NICS), and stability (S0-T1 splitting) properties. The findings reveal that appropriate π-electron-donating and π-electron-accepting substituents with suitable size and symmetry can interact with the π-system of the ring, significantly influencing π-electron delocalization. While the charge factor has a minimal impact on π-electron delocalization, the presence of a pz orbital capable of interacting with the π-electron delocalization is the primary factor leading to a deviation from the typical aromaticity characteristics observed in benzene.

3.
Cell Tissue Res ; 396(2): 141-155, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38539007

RESUMO

Telocytes (TCs) are CD34-positive interstitial cells that have long cytoplasmic projections, called telopodes; they have been identified in several organs and in various species. These cells establish a complex communication network between different stromal and epithelial cell types, and there is growing evidence that they play a key role in physiology and pathology. In many tissues, TC network impairment has been implicated in the onset and progression of pathological conditions, which makes the study of TCs of great interest for the development of novel therapies. In this review, we summarise the main methods involved in the characterisation of these cells as well as their inherent difficulties and then discuss the functional assays that are used to uncover the role of TCs in normal and pathological conditions, from the most traditional to the most recent. Furthermore, we provide future perspectives in the study of TCs, especially regarding the establishment of more precise markers, commercial lineages and means for drug delivery and genetic editing that directly target TCs.


Assuntos
Telócitos , Telócitos/citologia , Telócitos/metabolismo , Humanos , Animais
4.
Colorectal Dis ; 26(3): 466-475, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38243617

RESUMO

AIM: Locally advanced rectal cancer (LARC) is commonly treated with neoadjuvant chemoradiotherapy (nCRT) and total mesorectal excision (TME) to reduce local recurrence (LR) and improve survival. However, LR, particularly associated with lateral lymph node (LLN) involvement, remains a concern. The aim of this study was to investigate preoperative factors associated with LLN involvement and their impact on LR rates in LARC patients undergoing nCRT and curative surgery. METHOD: This multicentre retrospective study, including four academic high-volume institutions, involved 301 consecutive adult LARC patients treated with nCRT and curative surgery between January 2014 and December 2019 who did not undergo lateral lymph node dissection (LLND). Baseline and restaging pelvic MRIs were evaluated for suspicious LLNs based on institutional criteria. Patients were divided into two groups: cLLN+ (positive nodes) and cLLN- (no suspicious nodes). Primary outcome measures were LR and lateral local recurrence (LLR) rates at 3 years. RESULTS: Among the cohort, 15.9% had suspicious LLNs on baseline MRI, and 9.3% had abnormal LLNs on restaging MRI. At 3 years, LR and LLR rates were 4.0% and 1.0%, respectively. Ten out of 12 (83.3%) patients with LR showed no suspicious LLNs at the baseline MRI. Abnormal LLNs on MRI were not independent risk factors for LR, distant recurrence or disease-free survival. CONCLUSION: Abnormal LLNs on baseline and restaging MRI assessment did not impact LR and LLR rates in this cohort of patients with LARC submitted to nCRT and curative TME surgery.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Adulto , Humanos , Quimiorradioterapia/métodos , Excisão de Linfonodo/métodos , Linfonodos/patologia , Metástase Linfática/patologia , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Estudos Retrospectivos
5.
J Dairy Sci ; 107(4): 2390-2405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37923203

RESUMO

A study was conducted at 3 commercial dairies in California to compare outcomes of treating nonsevere (mild and moderate) gram-negative (GN) clinical mastitis (CM) with intramammary (IMM) ceftiofur HCl (125 mg of ceftiofur HCl per tube) in either 2-d (SP2) or 5-d (SP5) treatment programs compared with nontreatment (CON). In addition, we contrasted results from cases classified as mild and moderate. Four hundred fifteen cases were included in the final dataset, including 135 CON, 133 SP2, and 147 SP5. Milk from quarters with CM was sampled for on-farm culture (OFC) to differentiate gram-positive (GP) and GN bacteria, with results known within 24 h. Those with GN infections were randomly assigned to experimental groups, while those with GP, mixed infections, and contaminated samples did not continue in the study and received standard farm therapy. For cows with GN infections, a sample was submitted for MALDI-TOF assay. Only nonsevere cases were enrolled, and all quarters yielded monocultures of GN species. Clinical scores were obtained 0, 1, 2, 3, 4, 5, 14, 21, and 28 ± 3 d relative to enrollment. Milk samples were collected from quarters 14, 21, and 28 ± 3 d after enrollment, and submitted for routine culture and, when appropriate, submitted to MALDI-TOF evaluation. For many response criteria, there were significant interactions between treatments and CM severity scores at the time of enrollment, with effectiveness of ceftiofur HCl treatment being more beneficial compared with CON as mastitis clinical severity increased. While most treatment responses were significant for animals with mild or moderate GN mastitis, the largest responses were noted among cows with moderate CM cases.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Feminino , Animais , Bovinos , Antibacterianos/uso terapêutico , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Cefalosporinas/uso terapêutico , Leite , Doenças dos Bovinos/tratamento farmacológico
6.
An Acad Bras Cienc ; 96(1): e20230114, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808811

RESUMO

Self-medication (SM) is the practice of consuming medicines without a prescription. Despite being a potentially dangerous action, SM is practiced globally and has been highlighted during the COVID-19 pandemic. The aim of this study was to evaluate SM for the prevention or treatment of COVID-19 and the factors associated with this practice among undergraduate students in Southern Brazil. A cross-sectional study was conducted between July and November 2020 using an electronic questionnaire to collect information about the practice of SM and the associated sociodemographic characteristics, health perception, and lifestyle. We collected 1,553 responses and identified a prevalence of 14.9% for SM. The risk factors for SM were earning between BRL 2,101 and BRL 5,250, studying at a public university, and studying a distance undergraduate course. The protective factors were age above 30 years, female sex, working or participating in internships, occasionally recommending their own medications to other people, and worsening health during the pandemic. The main drugs or products used were ivermectin, vitamins C and D, tea, azithromycin, zinc, and propolis. Our data could help in the development of health education measures to reduce SM among undergraduate students and guide the population regarding the risks of this practice.


Assuntos
COVID-19 , Automedicação , Estudantes , Humanos , Feminino , Brasil/epidemiologia , Automedicação/estatística & dados numéricos , Masculino , Estudos Transversais , COVID-19/prevenção & controle , COVID-19/epidemiologia , Estudantes/estatística & dados numéricos , Adulto Jovem , Adulto , Prevalência , Universidades , SARS-CoV-2 , Inquéritos e Questionários , Fatores de Risco , Adolescente , Tratamento Farmacológico da COVID-19 , Pandemias/prevenção & controle
7.
Behav Res Methods ; 56(3): 1852-1862, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37326772

RESUMO

A popular approach to the simulation of multivariate, non-normal data in the social sciences is to define a multivariate normal distribution first, and then alter its lower-dimensional marginals to achieve the shape of the distribution intended by the researchers. A consequence of this process is that the correlation structure is altered, so further methods are needed to specify an intermediate correlation matrix in the multivariate normal distribution step. Most of the techniques available in the literature estimate this intermediate correlation matrix bivariately (i.e., correlation by correlation), risking the possibility of generating a non-positive definite matrix. The present article addresses this issue by offering an algorithm that estimates all elements of the intermediate correlation matrix simultaneously, through stochastic approximation. A small simulation study demonstrates the feasibility of the present method to induce the correlation structure both in simulated and empirical data.


Assuntos
Algoritmos , Humanos , Método de Monte Carlo , Simulação por Computador
8.
J Biol Chem ; 298(9): 102277, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35863436

RESUMO

La-related protein 1 (LARP1) has been identified as a key translational inhibitor of terminal oligopyrimidine (TOP) mRNAs downstream of the nutrient sensing protein kinase complex, mTORC1. LARP1 exerts this inhibitory effect on TOP mRNA translation by binding to the mRNA cap and the adjacent 5'TOP motif, resulting in the displacement of the cap-binding protein eIF4E from TOP mRNAs. However, the involvement of additional signaling pathway in regulating LARP1-mediated inhibition of TOP mRNA translation is largely unexplored. In the present study, we identify a second nutrient sensing kinase GCN2 that converges on LARP1 to control TOP mRNA translation. Using chromatin-immunoprecipitation followed by massive parallel sequencing (ChIP-seq) analysis of activating transcription factor 4 (ATF4), an effector of GCN2 in nutrient stress conditions, in WT and GCN2 KO mouse embryonic fibroblasts, we determined that LARP1 is a GCN2-dependent transcriptional target of ATF4. Moreover, we identified GCN1, a GCN2 activator, participates in a complex with LARP1 on stalled ribosomes, suggesting a role for GCN1 in LARP1-mediated translation inhibition in response to ribosome stalling. Therefore, our data suggest that the GCN2 pathway controls LARP1 activity via two mechanisms: ATF4-dependent transcriptional induction of LARP1 mRNA and GCN1-mediated recruitment of LARP1 to stalled ribosomes.


Assuntos
Aminoácidos , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases , Sequência de Oligopirimidina na Região 5' Terminal do RNA , RNA Mensageiro , Proteínas de Ligação a RNA , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos/metabolismo , Animais , Técnicas de Cultura de Células , Imunoprecipitação da Cromatina , Fator de Iniciação 4E em Eucariotos/metabolismo , Fibroblastos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
9.
J Comput Chem ; 44(6): 755-765, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36373956

RESUMO

The chemical stability and the low-lying singlet and triplet excited states of BN-n-acenes (n = 1-7) were studied using single reference and multireference methodologies. From the calculations, descriptors such as the singlet-triplet splitting, the natural orbital (NO) occupations and aromaticity indexes are used to provide structural and energetic analysis. The boron and nitrogen atoms form an isoelectronic pair of two carbon atoms, which was used for the complete substitution of these units in the acene series. The structural analysis confirms the effects originated from the insertion of a uniform pattern of electronegativity difference within the molecular systems. The covalent bonds tend to be strongly polarized which does not happen in the case of a carbon-only framework. This effect leads to a charge transfer between neighbor atoms resulting in a more strengthened structure, keeping the aromaticity roughly constant along the chain. The singlet-triplet splitting also agrees with this stability trend, maintaining a consistent gap value for all molecules. The BN-n-acenes molecules possess a ground state with monoconfigurational character indicating their electronic stability. The low-lying singlet excited states have charge transfer character, which proceeds from nitrogen to boron.

10.
Opt Express ; 31(24): 40041-40055, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041314

RESUMO

The pursuit of high-power solar laser systems with high efficiency and capacity for large tracking error compensation is determinant for the applicability of this renewable technology. A side-pumped dual-rod Ce:Nd:YAG solar laser was developed and tested at the focus of a 2 m diameter parabolic concentrator. Maximum continuous-wave total solar laser power of 58 W was measured. To the best of our knowledge, this is the highest laser power from a Ce:NdYAG solar laser. Moreover, wide tracking error compensation width of 5.1° in the azimuthal direction was reached, being 4.25 times higher than the previous measurement without solar tracking assistance.

11.
Ecol Appl ; 33(2): e2801, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36546604

RESUMO

Agricultural expansion and intensification are major drivers of global change. Quantifying the importance of different processes governing the assembly of local communities in agroecosystems is essential to guide the conservation effort allocated to enhancing habitat connectivity, improving habitat quality or managing species interactions. We used multiple detection methods to record the occurrence of medium-sized and large-sized mammals in three managed landscapes of a heterogeneous Mediterranean region. Then we used a joint species distribution model to evaluate the relative influence of dispersal limitation, environmental filtering, and interspecific interactions on the local assembly of mammal communities in 4-km2 plots. The partitioning of the explained variation in species occurrence was attributed on average 99% to environmental filters and 1% to dispersal filters. No role was attributed to biotic filters, in agreement with the scarce support for strong competition or other negative interactions found after a literature review. Four principal environmental factors explained on average 63% of variance in species occurrence and operated mainly at the landscape scale. The amount of shrub cover in the neighboring landscape was the most influential factor favoring mammal occurrence and accounted for nearly one-third of the total variance. The proportion of intensively managed croplands and proxies of human activity within landscape samples limited mammal presence. At the microhabitat scale (~80 m2 plots) the mean percentage area deprived of woody vegetation also had a negative effect. Functional traits such as body mass or social behavior accounted for a substantial fraction of the variation attributed to environmental factors. We concluded that multiscale environmental filtering governed local community assembly, whereas the role of dispersal limitation and interspecific interactions was negligible. Our results suggest that further removal of shrubland, the expansion of intensive agriculture, and the increase of human activity are expected to result in species losses. The fact that community integrity responds to a single type of ecological process simplifies practical recommendations. Management strategies should focus on the conservation and restoration of shrubland, adopting alternatives to intensive schemes of agricultural production, and minimizing recreational and other human activities in remnant natural habitats within agroecosystems or mosaic landscapes.


Assuntos
Biodiversidade , Ecossistema , Animais , Humanos , Mamíferos , Agricultura/métodos , Região do Mediterrâneo
12.
Chem Rev ; 121(22): 14088-14188, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34415732

RESUMO

This review considers the most recent developments in supramolecular and supraparticle structures obtained from natural, renewable biopolymers as well as their disassembly and reassembly into engineered materials. We introduce the main interactions that control bottom-up synthesis and top-down design at different length scales, highlighting the promise of natural biopolymers and associated building blocks. The latter have become main actors in the recent surge of the scientific and patent literature related to the subject. Such developments make prominent use of multicomponent and hierarchical polymeric assemblies and structures that contain polysaccharides (cellulose, chitin, and others), polyphenols (lignins, tannins), and proteins (soy, whey, silk, and other proteins). We offer a comprehensive discussion about the interactions that exist in their native architectures (including multicomponent and composite forms), the chemical modification of polysaccharides and their deconstruction into high axial aspect nanofibers and nanorods. We reflect on the availability and suitability of the latter types of building blocks to enable superstructures and colloidal associations. As far as processing, we describe the most relevant transitions, from the solution to the gel state and the routes that can be used to arrive to consolidated materials with prescribed properties. We highlight the implementation of supramolecular and superstructures in different technological fields that exploit the synergies exhibited by renewable polymers and biocolloids integrated in structured materials.


Assuntos
Nanofibras , Polímeros , Biopolímeros/química , Celulose , Nanofibras/química , Seda/química
13.
Genet Sel Evol ; 55(1): 57, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550618

RESUMO

BACKGROUND: Most genomic prediction applications in animal breeding use genotypes with tens of thousands of single nucleotide polymorphisms (SNPs). However, modern sequencing technologies and imputation algorithms can generate ultra-high-density genotypes (including millions of SNPs) at an affordable cost. Empirical studies have not produced clear evidence that using ultra-high-density genotypes can significantly improve prediction accuracy. However, (whole-genome) prediction accuracy is not very informative about the ability of a model to capture the genetic signals from specific genomic regions. To address this problem, we propose a simple methodology that detects chromosome regions for which a specific model (e.g., single-step genomic best linear unbiased prediction (ssGBLUP)) may fail to fully capture the genetic signal present in such segments-a phenomenon that we refer to as signal leakage. We propose to detect regions with evidence of signal leakage by testing the association of residuals from a pedigree or a genomic model with SNP genotypes. We discuss how this approach can be used to map regions with signals that are poorly captured by a model and to identify strategies to fix those problems (e.g., using a different prior or increasing marker density). Finally, we explored the proposed approach to scan for signal leakage of different models (pedigree-based, ssGBLUP, and various Bayesian models) applied to growth-related phenotypes (average daily gain and backfat thickness) in pigs. RESULTS: We report widespread evidence of signal leakage for pedigree-based models. Including a percentage of animals with SNP data in ssGBLUP reduced the extent of signal leakage. However, local peaks of missed signals remained in some regions, even when all animals were genotyped. Using variable selection priors solves leakage points that are caused by excessive shrinkage of marker effects. Nevertheless, these models still miss signals in some regions due to low linkage disequilibrium between the SNPs on the array used and causal variants. Thus, we discuss how such problems could be addressed by adding sequence SNPs from those regions to the prediction model. CONCLUSIONS: Residual single-marker regression analysis is a simple approach that can be used to detect regional genomic signals that are poorly captured by a model and to indicate ways to fix such problems.


Assuntos
Genoma , Genômica , Animais , Suínos , Teorema de Bayes , Genômica/métodos , Genótipo , Fenótipo , Polimorfismo de Nucleotídeo Único , Linhagem , Modelos Genéticos
14.
Appl Opt ; 62(10): 2697-2706, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132823

RESUMO

Solar laser technology typically requires a highly accurate solar tracking system that operates continuously, which increases energy consumption and reduces the system's lifetime. We propose a multi-rod solar laser pumping approach to enhance solar laser stability under non-continuous solar tracking conditions. Using a heliostat, solar radiation is redirected toward a first-stage parabolic concentrator. At its focus, an aspheric lens further concentrates the solar rays onto five Nd:YAG rods positioned within an elliptical-shaped pump cavity. Numerical analysis using Zemax and LASCAD software showed that the tracking error width at 10% laser power loss for the five 6.5 mm diameter and 15 mm length rods was 2.20°, which is 50% higher than that of the solar laser in previous non-continuous solar tracking experiments. 2.0% solar-to-laser conversion efficiency was also attained.

15.
Nucleic Acids Res ; 49(1): 458-478, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33332560

RESUMO

The mammalian target of rapamycin (mTOR) is a critical regulator of cell growth, integrating multiple signalling cues and pathways. Key among the downstream activities of mTOR is the control of the protein synthesis machinery. This is achieved, in part, via the co-ordinated regulation of mRNAs that contain a terminal oligopyrimidine tract (TOP) at their 5'ends, although the mechanisms by which this occurs downstream of mTOR signalling are still unclear. We used RNA-binding protein (RBP) capture to identify changes in the protein-RNA interaction landscape following mTOR inhibition. Upon mTOR inhibition, the binding of LARP1 to a number of mRNAs, including TOP-containing mRNAs, increased. Importantly, non-TOP-containing mRNAs bound by LARP1 are in a translationally-repressed state, even under control conditions. The mRNA interactome of the LARP1-associated protein PABPC1 was found to have a high degree of overlap with that of LARP1 and our data show that PABPC1 is required for the association of LARP1 with its specific mRNA targets. Finally, we demonstrate that mRNAs, including those encoding proteins critical for cell growth and survival, are translationally repressed when bound by both LARP1 and PABPC1.


Assuntos
Autoantígenos/fisiologia , Proteína I de Ligação a Poli(A)/fisiologia , Polirribossomos/metabolismo , Biossíntese de Proteínas/fisiologia , RNA Mensageiro/metabolismo , Ribonucleoproteínas/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Regiões 5' não Traduzidas/genética , Autoantígenos/genética , Regulação da Expressão Gênica , Genes Reporter , Células HeLa , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Naftiridinas/farmacologia , Mutação Puntual , Biossíntese de Proteínas/genética , Interferência de RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Ribonucleoproteínas/genética , Antígeno SS-B
16.
Nucleic Acids Res ; 49(6): 3461-3489, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33398329

RESUMO

LARP1 is a key repressor of TOP mRNA translation. It binds the m7Gppp cap moiety and the adjacent 5'TOP motif of TOP mRNAs, thus impeding the assembly of the eIF4F complex on these transcripts. mTORC1 controls TOP mRNA translation via LARP1, but the details of the mechanism are unclear. Herein we elucidate the mechanism by which mTORC1 controls LARP1's translation repression activity. We demonstrate that mTORC1 phosphorylates LARP1 in vitro and in vivo, activities that are efficiently inhibited by rapamycin and torin1. We uncover 26 rapamycin-sensitive phospho-serine and -threonine residues on LARP1 that are distributed in 7 clusters. Our data show that phosphorylation of a cluster of residues located proximally to the m7Gppp cap-binding DM15 region is particularly sensitive to rapamycin and regulates both the RNA-binding and the translation inhibitory activities of LARP1. Our results unravel a new model of translation control in which the La module (LaMod) and DM15 region of LARP1, both of which can directly interact with TOP mRNA, are differentially regulated: the LaMod remains constitutively bound to PABP (irrespective of the activation status of mTORC1), while the C-terminal DM15 'pendular hook' engages the TOP mRNA 5'-end to repress translation, but only in conditions of mTORC1 inhibition.


Assuntos
Autoantígenos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Biossíntese de Proteínas , Ribonucleoproteínas/metabolismo , Motivos de Aminoácidos , Autoantígenos/química , Células HEK293 , Humanos , Naftiridinas/farmacologia , Fosforilação/efeitos dos fármacos , Ligação Proteica , Ribonucleoproteínas/química , Serina/metabolismo , Sirolimo/farmacologia , Treonina/metabolismo , Tirosina/metabolismo , Antígeno SS-B
17.
J Dairy Sci ; 106(11): 7725-7736, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641343

RESUMO

Automatic milking system (AMS) adoption in the United States is trending upward, with issues such as lower availability and increased cost of labor being factors frequently listed as motives for AMS implementation. In addition, more interest in precision dairy farming by the new generation of farmers may also help increase AMS adoption. The objective of this scoping review was to characterize the nature of the literature investigating non-pasture-based AMS and the opportunities and challenges for future research. The eligibility criteria included studies published in or after the year 2000, with full text in English, of at least 500 words, examining various outcomes related to AMS in non-pasture-based dairy farms. Six electronic databases were searched: Biosis (Web of Science), CAB Abstracts (CAB Direct), Medline (PubMed), PubAg, AGRIS (FAO), and Scopus (Elsevier). The review focused on studies with objectives, characteristics, farms, and AMS information. A total of 4,292 titles and abstracts were screened, and 536 studies were finally included. Most of the studies were conducted in Europe (73.5%), among commercial herds (67.9%), comprising Holstein cows (57.7%), using Lely and DeLaval brands (45.4% vs. 39.7%), with free-flow traffic (52.7%). The main research topics investigated were milk production, milk composition, and AMS efficiency, followed by behavior and welfare, health disorders (especially mastitis), and nutrition in Europe and other regions. At the same time, in the United States, trends were similar, except for nutrition. Since 2016, there has been an increased interest in studies on energy and water consumption, technological development, environment (enteric emissions), reproduction, genetics, and longevity or culling. However, the small number of studies and unclear characterization of what is optimum for reproductive management, other health disorders, economics, and water and energy consumption suggest a need for future research.

18.
Int J Mol Sci ; 24(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37958846

RESUMO

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults, with few effective treatment strategies. The research on the development of new treatments is often constrained by the limitations of preclinical models, which fail to accurately replicate the disease's essential characteristics. Herein, we describe the obtention, molecular, and functional characterization of the GBM33 cell line. This cell line belongs to the GBM class according to the World Health Organization 2021 Classification of Central Nervous System Tumors, identified by methylation profiling. GBM33 expresses the astrocytic marker GFAP, as well as markers of neuronal origin commonly expressed in GBM cells, such as ßIII-tubulin and neurofilament. Functional assays demonstrated an increased growth rate when compared to the U87 commercial cell line and a similar sensitivity to temozolamide. GBM33 cells retained response to serum starvation, with reduced growth and diminished activation of the Akt signaling pathway. Unlike LN-18 and LN-229 commercial cell lines, GBM33 is able to produce primary cilia upon serum starvation. In summary, the successful establishment and comprehensive characterization of this GBM cell line provide researchers with invaluable tools for studying GBM biology, identifying novel therapeutic targets, and evaluating the efficacy of potential treatments.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/metabolismo , Brasil , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Tubulina (Proteína)/metabolismo
19.
Molecules ; 28(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36838580

RESUMO

This work reports an experimental study aiming to determine the thermodynamic properties of five chlorinated compounds with environmental impact. The vapor pressures of the crystalline phases of three isomers of dichlorobenzoic acid (2,4-, 2,5-, and 2,6-) and 2,6-dichlorobenzonitrile were measured at several temperatures using the Knudsen effusion technique. Another technique (a static method based on capacitance diaphragm manometers) allowed the measurement of the vapor pressures of both the crystalline and liquid phases of 2,4-dichlorobenzonitrile between 303.0 and 380.0 K. This latter technique also enabled the measurement of sublimation vapor pressures of 2,6-dichlorobenzonitrile over a larger range interval of temperatures, T = 328.7 and 391.8 K. The standard molar enthalpy, entropy, and Gibbs energy of sublimation (for all the compounds studied) and vaporization (for 2,4-dichlorobenzonitrile) were derived, at reference temperatures, from the experimental vapor pressure results. The temperatures and enthalpies of fusion and the isobaric heat capacities of the five crystalline-substituted benzenes were determined using differential scanning calorimetry. The contributions of the three substituents (-COOH, -CN, and -Cl) to the sublimation thermodynamic properties of the compounds studied were discussed.


Assuntos
Benzeno , Termodinâmica , Temperatura , Entropia , Volatilização
20.
World J Microbiol Biotechnol ; 39(11): 287, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37632593

RESUMO

The fungi-based technology provided encouraging scenarios in the transition from a conventionally based economic system to the potential security of sources closely associated with the agricultural sphere such as the agriculture. In recent years, the intensification of fungi-based processes has generated significant gains, additionally to the production of materials with significant benefits and strong environmental importance. Furthermore, the growing concern for human health, especially in the agriculture scenario, has fostered the investigation of organisms with high biological and beneficial potential for use in agricultural systems. Accordingly, this study offered a comprehensive review of the diversity of the soil fungal microbiome and its main applications in a biotechnological approach aimed at agriculture and food chain-related areas. Moreover, the spectrum of opportunities and the extensive optimization platform for obtaining fungi compounds and metabolites are discussed. Finally, future perspectives regarding the insurgency of innovations and challenges on the broad rise of visionary solutions applied to the biotechnology context are provided.


Assuntos
Micobioma , Solo , Humanos , Agricultura , Biotecnologia , Cadeia Alimentar
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