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1.
Biochem Pharmacol ; 225: 116264, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38710334

RESUMO

The retrosplenial cortex (RSC) plays a central role in processing contextual fear conditioning. In addition to corticocortical and thalamocortical projections, the RSC receives subcortical inputs, including a substantial projection from the nucleus incertus in the pontine tegmentum. This GABAergic projection contains the neuropeptide, relaxin-3 (RLN3), which inhibits target neurons via its Gi/o-protein-coupled receptor, RXFP3. To assess this peptidergic system role in contextual fear conditioning, we bilaterally injected the RSC of adult rats with an adeno-associated-virus (AAV), expressing the chimeric RXFP3 agonist R3/I5 or a control AAV, and subjected them to contextual fear conditioning. The R3/I5 injected rats did not display any major differences to control-injected and naïve rats but displayed a significantly delayed extinction. Subsequently, we employed acute bilateral injections of the specific RXFP3 agonist peptide, RXFP3-Analogue 2 (A2), into RSC. While the administration of A2 before each extinction trial had no impact on the extinction process, treatment with A2 before each acquisition trial resulted in delayed extinction. In related anatomical studies, we detected an enrichment of RLN3-immunoreactive nerve fibers in deep layers of the RSC, and a higher level of co-localization of RXFP3 mRNA with vesicular GABA transporter (vGAT) mRNA than with vesicular glutamate transporter-1 (vGLUT1) mRNA across the RSC, consistent with an effect of RLN3/RXFP3 signalling on the intrinsic, inhibitory circuits within the RSC. These findings suggest that contextual conditioning processes in the RSC involve, in part, RLN3 afferent modulation of local inhibitory neurons that provides a stronger memory acquisition which, in turn, retards the extinction process.

2.
Behav Brain Res ; 462: 114874, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38266780

RESUMO

Contextual fear conditioning is a behavioral paradigm used to assess hippocampal-dependent memory in experimental animals. Perception of the context depends on activation of a distinct population of neurons in the hippocampus and in hippocampal-related areas that process discrete aspects of context perception. In the absence of any putatively associated cue, the context becomes the salient element that may warn of an upcoming aversive event; and in particular conditions, animals generalize this warning to any new or similar context. In this study we evaluated the effects of the number of sessions, the number of unconditioned stimuli per acquisition session and the distribution of extinction sessions to assess fear acquisition and extinction and determine under which conditions generalization occurred in adult, male rats. We observed that the organization and spacing of sessions were relevant factors in the acquisition and extinction of contextual fear memories. Extinction occurred with significantly greater robustness when sessions were spread over two days. Furthermore, results indicated that exposure to a single 0.3 mA, 0.5 s footshock in two different sessions could produce context-specific fear, while more acquisition sessions or more footshocks within a single session produced a generalization of the fear response to a new context. Notably, when generalization occurred, successive re-exposure to the generalized context produced extinction in a similar way to the paired exposure. Together, the present findings identify clear procedural and behavioral parameters amenable to neural systems analysis of three clinically relevant outcomes of contextual fear conditioning, i.e., memory acquisition, storage and extinction.


Assuntos
Extinção Psicológica , Medo , Ratos , Masculino , Animais , Extinção Psicológica/fisiologia , Medo/fisiologia , Memória/fisiologia , Condicionamento Clássico/fisiologia , Hipocampo/fisiologia
3.
Pathophysiology ; 30(3): 389-399, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37755396

RESUMO

In this article, we discuss a class of MYC-interacting lncRNAs (long non-coding RNAs) that share the following criteria: They are direct transcriptional targets of MYC. Their expression is coordinated with the expression of MYC. They are required for sustained MYC-driven cell proliferation, and they are not essential for cell survival. We refer to these lncRNAs as "MYC facilitators" and discuss two representative members of this class of lncRNAs, SNHG17 (small nuclear RNA host gene) and LNROP (long non-coding regulator of POU2F2). We also present a general hypothesis on the role of lncRNAs in MYC-mediated transcriptional regulation.

4.
Sensors (Basel) ; 23(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37430900

RESUMO

Underwater imaging has been present for many decades due to its relevance in vision and navigation systems. In recent years, advances in robotics have led to the availability of autonomous or unmanned underwater vehicles (AUVs, UUVs). Despite the rapid development of new studies and promising algorithms in this field, there is currently a lack of research toward standardized, general-approach proposals. This issue has been stated in the literature as a limiting factor to be addressed in the future. The key starting point of this work is to identify a synergistic effect between professional photography and scientific fields by analyzing image acquisition issues. Subsequently, we discuss underwater image enhancement and quality assessment, image mosaicking and algorithmic concerns as the last processing step. In this line, statistics about 120 AUV articles fro recent decades have been analyzed, with a special focus on state-of-the-art papers from recent years. Therefore, the aim of this paper is to identify critical issues in autonomous underwater vehicles encompassing the entire process, starting from optical issues in image sensing and ending with some issues related to algorithmic processing. In addition, a global underwater workflow is proposed, extracting future requirements, outcome effects and new perspectives in this context.

5.
PLoS Genet ; 19(5): e1010774, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37216416

RESUMO

Pbp1 (poly(A)-binding protein-binding protein 1) is a cytoplasmic stress granule marker that is capable of forming condensates that function in the negative regulation of TORC1 signaling under respiratory conditions. Polyglutamine expansions in its mammalian ortholog ataxin-2 lead to spinocerebellar dysfunction due to toxic protein aggregation. Here, we show that loss of Pbp1 in S. cerevisiae leads to decreased amounts of mRNAs and mitochondrial proteins which are targets of Puf3, a member of the PUF (Pumilio and FBF) family of RNA-binding proteins. We found that Pbp1 supports the translation of Puf3-target mRNAs in respiratory conditions, such as those involved in the assembly of cytochrome c oxidase and subunits of mitochondrial ribosomes. We further show that Pbp1 and Puf3 interact through their respective low complexity domains, which is required for Puf3-target mRNA translation. Our findings reveal a key role for Pbp1-containing assemblies in enabling the translation of mRNAs critical for mitochondrial biogenesis and respiration. They may further explain prior associations of Pbp1/ataxin-2 with RNA, stress granule biology, mitochondrial function, and neuronal health.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Animais , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Ataxina-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biogênese de Organelas , Proteínas de Ligação a RNA/metabolismo , Mamíferos/genética , Proteínas de Transporte/genética
6.
Cell Death Dis ; 14(2): 168, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849510

RESUMO

MYC controls most of the non-coding genome. Several long noncoding transcripts were originally identified in the human B cell line P496-3 and then shown to be required for MYC-driven proliferation of Burkitt lymphoma-derived RAMOS cells. In this study, we used RAMOS cells exclusively as a representative of the human B cell lineage. One of the MYC-controlled lncRNAs required for RAMOS cell proliferation is ENSG00000254887 which we will term LNROP (long non-coding regulator of POU2F2). In the genome, LNROP is located in close proximity of POU2F2, the gene encoding OCT2. OCT2 is a transcription factor with important roles in sustaining the proliferation of human B cells. Here we show that LNROP is a nuclear RNA and a direct target of MYC. Downregulation of LNROP attenuates the expression of OCT2. This effect of LNROP on the expression of OCT2 is unidirectional as downregulation of OCT2 does not alter the expression of LNROP. Our data suggest that LNROP is a cis-acting regulator of OCT2. To illustrate the downstream reach of LNROP, we chose a prominent target of OCT2, the tyrosine phosphatase SHP-1. Downregulation of OCT2 elevates the expression of SHP-1. Our data suggest the following path of interactions: LNROP enables the proliferation of B cells by positively and unidirectionally regulating the growth-stimulatory transcription factor OCT2. In actively proliferating B cells, OCT2 attenuates the expression and anti-proliferative activity of SHP-1.


Assuntos
Linfoma de Burkitt , RNA Longo não Codificante , Humanos , Linfócitos B , Proliferação de Células/genética , RNA Longo não Codificante/genética , Fatores de Transcrição
7.
iScience ; 25(5): 104334, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35602938

RESUMO

Targeted therapies for epilepsies associated with the mTORC1 signaling negative regulator GATOR1 are lacking. NPRL2 is a subunit of the GATOR1 complex and mutations in GATOR1 subunits, including NPRL2, are associated with epilepsy. To delineate the mechanisms underlying NPRL2-related epilepsies, we created a mouse (Mus musculus) model with neocortical loss of Nprl2. Mutant mice have increased mTORC1 signaling and exhibit spontaneous seizures. They also display abnormal synaptic function characterized by increased evoked and spontaneous EPSC and decreased evoked and spontaneous IPSC frequencies, respectively. Proteomic and metabolomics studies of Nprl2 mutants revealed alterations in known epilepsy-implicated proteins and metabolic pathways, including increases in the neurotransmitter, glycine. Furthermore, glycine actions on the NMDA receptor contribute to the electrophysiological and survival phenotypes of these mice. Taken together, in this neuronal Nprl2 model, we delineate underlying molecular, metabolic, and electrophysiological mechanisms contributing to mTORC1-related epilepsy, providing potential therapeutic targets for epilepsy.

8.
Sci Rep ; 12(1): 6408, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35436992

RESUMO

Inosine triphosphate pyrophosphatases (ITPases) are ubiquitous house-cleaning enzymes that specifically recognize deaminated purine nucleotides and catalyze their hydrolytic cleavage. In this work, we have characterized the Trypanosoma brucei ITPase ortholog (TbITPA). Recombinant TbITPA efficiently hydrolyzes (deoxy)ITP and XTP nucleotides into their respective monophosphate form. Immunolocalization analysis performed in bloodstream forms suggests that the primary role of TbITPA is the exclusion of deaminated purines from the cytosolic nucleoside triphosphate pools. Even though ITPA-knockout bloodstream parasites are viable, they are more sensitive to inhibition of IMP dehydrogenase with mycophenolic acid, likely due to an expansion of IMP, the ITP precursor. On the other hand, TbITPA can also hydrolyze the activated form of the antiviral ribavirin although in this case, the absence of ITPase activity in the cell confers protection against this nucleoside analog. This unexpected phenotype is dependant on purine availability and can be explained by the fact that ribavirin monophosphate, the reaction product generated by TbITPA, is a potent inhibitor of trypanosomal IMP dehydrogenase and GMP reductase. In summary, the present study constitutes the first report on a protozoan inosine triphosphate pyrophosphatase involved in the removal of harmful deaminated nucleotides from the cytosolic pool.


Assuntos
Nucleotídeos , Trypanosoma brucei brucei , IMP Desidrogenase , Inosina , Inosina Trifosfato , Pirofosfatases/genética , Ribavirina/farmacologia
9.
Food Chem ; 383: 132371, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35176716

RESUMO

The extraordinary organoleptic qualities of Iberian ham derive from the singular producing pig breed and from the traditional rearing conditions, both of which define its lipid content and composition. In this work 1H NMR spectroscopy is used for the first time to analyse the lipid profile of Iberian hams as determinant of quality. Quantification of fatty acids is readily obtained from the spectra, with the monounsaturated fatty acids standing out, especially in the higher quality hams. Unprecedently, triacylglyceride hydrolysis products formed during the curing process can also be directly detected and quantified. Furthermore, chemometric analysis of the NMR data allows to classify Iberian hams according to the pig's crossbreed and feeding regime. Principal component analysis shows fatty acid unsaturation and triacylglyceride hydrolysis as discriminating variables. 1H NMR spectroscopy has thus revealed as a convenient and powerful tool for the lipid analysis and classification of Iberian hams and for detection of fraud.


Assuntos
Produtos da Carne , Carne de Porco , Animais , Ácidos Graxos/análise , Manipulação de Alimentos/métodos , Produtos da Carne/análise , Espectroscopia de Prótons por Ressonância Magnética , Suínos
10.
PeerJ Comput Sci ; 7: e583, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34179451

RESUMO

The use of low-field magnetic resonance imaging (LF-MRI) scanners has increased in recent years. The low economic cost in comparison to high-field (HF-MRI) scanners and the ease of maintenance make this type of scanner the best choice for nonmedical purposes. However, LF-MRI scanners produce low-quality images, which encourages the identification of optimization procedures to generate the best possible images. In this paper, optimization of the image acquisition procedure for an LF-MRI scanner is presented, and predictive models are developed. The MRI acquisition procedure was optimized to determine the physicochemical characteristics of pork loin in a nondestructive way using MRI, feature extraction algorithms and data processing methods. The most critical parameters (relaxation times, repetition time, and echo time) of the LF-MRI scanner were optimized, presenting a procedure that could be easily reproduced in other environments or for other purposes. In addition, two feature extraction algorithms (gray level co-occurrence matrix (GLCM) and one point fractal texture algorithm (OPFTA)) were evaluated. The optimization procedure was validated by using several evaluation metrics, achieving reliable and accurate results (r > 0.85; weighted absolute percentage error (WAPE) lower than 0.1%; root mean square error of prediction (RMSEP) lower than 0.1%; true standard deviation (TSTD) lower than 2; and mean absolute error (MAE) lower than 2). These results support the high degree of feasibility and accuracy of the optimized procedure of LF-MRI acquisition. No other papers present a procedure to optimize the image acquisition process in LF-MRI. Eventually, the optimization procedure could be applied to other LF-MRI systems.

11.
Farm. hosp ; 45(3): 121-125, mayo-junio 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-218116

RESUMO

Objetivo: Efectividad y seguridad de atezolizumab, nivolumab y pembrolizumab en cáncer de pulmón no microcítico metastásico.Método: Estudio observacional retrospectivo en pacientes con cáncer de pulmón no microcítico metastásico tratados en segunda línea oposteriores. La efectividad fue evaluada mediante supervivencia globaly supervivencia libre de progresión. La toxicidad mediante los CriteriosComunes de Terminología de Efectos Adversos v5.0.Resultados: Se incluyeron 8 pacientes con atezolizumab, 19 con nivolumab y 16 con pembrolizumab. La mediana de supervivencia libre deprogresión con atezolizumab fue 9,6 meses (intervalo de confianza del95% [IC95%] 2-17,2), 12,6 meses (IC95% 6,9-18,2) para nivolumab y8,5 meses (IC95% 0-19) para pembrolizumab. La mediana de supervivencia global con nivolumab fue 13,4 meses (IC95% 6-20,9) y no se alcanzópara atezolizumab y pembrolizumab. Ambas fueron superiores para lospacientes con 0-1 metástasis para nivolumab y en los pacientes conECOG 0-1 para pembrolizumab. Alrededor de un 85% de los pacientessufrieron efectos adversos. Dos pacientes tratados con nivolumab experimentaron vitíligo, con una supervivencia global mayor de 2,5 años.Conclusiones: En la muestra analizada, la efectividad de nivolumabes menor en pacientes con dos o más metástasis, y la de pembrolizumabes menor en pacientes con ECOG 2. La aparición de vitíligo se relacionócon una respuesta duradera. (AU)


Objective: To determine the effectiveness and safety of atezolizumab,nivolumab and pembrolizumab in patients with non-small cell lung cancer.Method: This is a retrospective observational study including patientstreated in second line and beyond. The effectiveness of treatment wasassessed by means of overall survival and progression free survival measurements. Toxicity was described according to the Common Criteria forAdverse Event Terminology v5.0.Results: The study included 8 patients treated with atezolizumab,19 withnivolumab, and 16 with pembrolizumab. Median progression free survival with atezolizumab was 9.6 months (95%CI 2-17.2), 12.6 months(95%CI 6.9-18.2) for nivolumab, and 8.5 months (95%CI 0-19) for pembrolizumab. Median overall survival was 13.4 months (95%CI 6-20.9)for nivolumab. Both PFS and OS were statistically higher in patients withgrade 0-1 metastasis in the case of nivolumab, and in ECOG 0-1 patientsfor pembrolizumab. Median overall survival was not reached for atezolizumab or pembrolizumab. Around 85% of patients suffered adverse effectsof some degree. Two of the patients treated with nivolumab developedvitiligo. Overall survival of both was higher than 2.5 years.Conclusions: For the patients included in the sample, nivolumab wasless effective in those with two or more metastases; the effectiveness ofpembrolizumab was lower in ECOG-2 patients. Vitiligo was related to amore durable response to treatment. (AU)


Assuntos
Humanos , Anticorpos Monoclonais Humanizados , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico
12.
Farm Hosp ; 45(3): 121-125, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33941055

RESUMO

OBJECTIVE: To determine the effectiveness and safety of atezolizumab, nivolumab and pembrolizumab in patients with non-small  cell lung cancer. METHOD: This is a retrospective observational study including patients treated in second line and beyond. The effectiveness of treatment  was assessed by means of overall survival and progression free survival  measurements. Toxicity was described according to the Common Criteria  for Adverse Event Terminology v5.0. RESULTS: The study included 8 patients treated with atezolizumab,19 with nivolumab, and 16 with pembrolizumab. Median progression free  survival with atezolizumab was 9.6 months (95%CI 2-17.2), 12.6 months (95%CI 6.9-18.2) for nivolumab, and 8.5 months (95%CI 0-19)  for pembrolizumab. Median overall survival was 13.4 months (95%CI 6- 20.9) for nivolumab. Both PFS and OS were statistically higher in patients  with grade 0-1 metastasis in the case of nivolumab, and in ECOG 0-1  patients for pembrolizumab. Median overall survival was not reached for  atezolizumab or pembrolizumab. Around 85% of patients suffered adverse  effects of some degree. Two of the patients treated with nivolumab  developed vitiligo. Overall survival of both was higher than 2.5 years. CONCLUSIONS: For the patients included in the sample, nivolumab was less  effective in those with two or more metastases; the effectiveness of pembrolizumab was lower in ECOG-2 patients. Vitiligo was related to a more durable response to treatment.


Objetivo: Efectividad y seguridad de atezolizumab, nivolumab y  embrolizumab en cáncer de pulmón no microcítico metastásico.Método: Estudio observacional retrospectivo en pacientes con cáncer de  pulmón no microcítico metastásico tratados en segunda línea o posteriores. La efectividad fue evaluada mediante supervivencia global y  supervivencia libre de progresión. La toxicidad mediante los Criterios Comunes de Terminología de Efectos Adversos v5.0.Resultados: Se incluyeron 8 pacientes con atezolizumab, 19 con  nivolumab y 16 con pembrolizumab. La mediana de supervivencia libre de progresión con atezolizumab fue 9,6 meses (intervalo de confianza del 95% [IC95%] 2-17,2), 12,6 meses (IC95% 6,9-18,2) para nivolumab 8,5 meses (IC95% 0-19) para pembrolizumab. La mediana de  supervivencia global con nivolumab fue 13,4 meses (IC95% 6-20,9) y no  se alcanzó para atezolizumab y pembrolizumab. Ambas fueron superiores  para los pacientes con 0-1 metástasis para nivolumab y en los pacientes  con ECOG 0-1 para pembrolizumab. Alrededor de un 85% de los pacientes sufrieron efectos adversos. Dos pacientes tratados con  nivolumab experimentaron vitíligo, con una supervivencia global mayor de  2,5 años.Conclusiones: En la muestra analizada, la efectividad de nivolumab es  menor en pacientes con dos o más metástasis, y la de pembrolizumab es  menor en pacientes con ECOG 2. La aparición de vitíligo se relacionó con  una respuesta duradera.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico
13.
Meat Sci ; 172: 108340, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33129061

RESUMO

The development of non-destructive methodologies based on Hyperspectral Imaging (HSI), Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) techniques to determine quality characteristics of fresh meat has been reviewed in this study. It has been focused primarily on research published in the last decade, and has placed particular attention on the instrumentation, data acquisition and main applications of each technique, finding a wide variety of possibilities for systems and methodologies as well as evidence of accurate and promising results. Most samples analysed were pork and beef, followed by lamb and chicken, with few studies on fresh meat from rabbit and duck. The overall evaluation is that work has been performed primarily in an experimental way but generally still lacks real application in the meat industry. In that respect, these non-destructive techniques should be improved, especially regarding speed, price and influence of external factors.


Assuntos
Qualidade dos Alimentos , Carne/análise , Animais , Bovinos , Galinhas , Patos , Imageamento Hiperespectral/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Coelhos , Ovinos , Suínos
14.
Proc Natl Acad Sci U S A ; 117(12): 6571-6579, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32156728

RESUMO

MYC controls the transcription of large numbers of long noncoding RNAs (lncRNAs). Since MYC is a ubiquitous oncoprotein, some of these lncRNAs probably play a significant role in cancer. We applied CRISPR interference (CRISPRi) to the identification of MYC-regulated lncRNAs that are required for MYC-driven cell proliferation in the P493-6 and RAMOS human lymphoid cell lines. We identified 320 noncoding loci that play positive roles in cell growth. Transcriptional repression of any one of these lncRNAs reduces the proliferative capacity of the cells. Selected hits were validated by RT-qPCR and in CRISPRi competition assays with individual GFP-expressing sgRNA constructs. We also showed binding of MYC to the promoter of two candidate genes by chromatin immunoprecipitation. In the course of our studies, we discovered that the repressor domain SID (SIN3-interacting domain) derived from the MXD1 protein is highly effective in P493-6 and RAMOS cells in terms of the number of guides depleted in library screening and the extent of the induced transcriptional repression. In the cell lines used, SID is superior to the KRAB repressor domain, which serves routinely as a transcriptional repressor domain in CRISPRi. The SID transcriptional repressor domain is effective as a fusion to the MS2 aptamer binding protein MCP, allowing the construction of a doxycycline-regulatable CRISPRi system that allows controlled repression of targeted genes and will facilitate the functional analysis of growth-promoting lncRNAs.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proliferação de Células/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/genética , Proteínas Repressoras/metabolismo , Aptâmeros de Nucleotídeos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/química , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Proteína 9 Associada à CRISPR/genética , Proteínas do Capsídeo/metabolismo , Linhagem Celular Tumoral , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Humanos , Regiões Promotoras Genéticas , Domínios Proteicos , RNA Guia de Cinetoplastídeos , RNA Longo não Codificante/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Transcrição Gênica
15.
Sci Rep ; 10(1): 3069, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080237

RESUMO

Low blood phosphate (Pi) reduces muscle function in hypophosphatemic disorders. Which Pi transporters are required and whether hormonal changes due to hypophosphatemia contribute to muscle function is unknown. To address these questions we generated a series of conditional knockout mice lacking one or both house-keeping Pi transporters Pit1 and Pit2 in skeletal muscle (sm), using the postnatally expressed human skeletal actin-cre. Simultaneous conditional deletion of both transporters caused skeletal muscle atrophy, resulting in death by postnatal day P13. smPit1-/-, smPit2-/- and three allele mutants are fertile and have normal body weights, suggesting a high degree of redundance for the two transporters in skeletal muscle. However, these mice show a gene-dose dependent reduction in running activity also seen in another hypophosphatemic model (Hyp mice). In contrast to Hyp mice, grip strength is preserved. Further evaluation of the mechanism shows reduced ERK1/2 activation and stimulation of AMP kinase in skeletal muscle from smPit1-/-; smPit2-/- mice consistent with energy-stress. Similarly, C2C12 myoblasts show a reduced oxygen consumption rate mediated by Pi transport-dependent and ERK1/2-dependent metabolic Pi sensing pathways. In conclusion, we here show that Pit1 and Pit2 are essential for normal myofiber function and survival, insights which may improve management of hypophosphatemic myopathy.


Assuntos
Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Fator de Transcrição Pit-1/metabolismo , Alelos , Animais , Linhagem Celular , Sobrevivência Celular , Transporte de Elétrons , Metabolismo Energético , Força da Mão , Camundongos Knockout , Modelos Biológicos , Células Musculares/metabolismo , Necrose , Consumo de Oxigênio , Fosfatos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/deficiência , Fator de Transcrição Pit-1/deficiência
16.
Comput Methods Programs Biomed ; 182: 105042, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473444

RESUMO

BACKGROUND: Mobile apps have a great potential to support patients in healthcare, and to encourage healthy behavioral changes such as smoking cessation. Nevertheless, the user rejection levels are still high. A set of factors that has impact on the app effectiveness is related to the quality of those features that lead to positive user experiences when using the app. This work aims to evaluate the user experience, and more specifically the usability and the user satisfaction with a mobile application for smoking cessation. This will also provide a basis for future improvements. METHODS: We provided a smoking cessation mobile Android app to two different user cohorts, the smokers as valid users and the experts, for three weeks. The app featured usual functionalities to help quit smoking, including an achieved benefits section, mini-games to distract during cravings, and supportive motivational messages. We collected information about user experience, through game playability and message satisfaction questionnaires, and the experts' opinions. We also considered usage of app sections, the duration of the mini-game sessions, and the user ratings for motivational messages. RESULTS: We included 45 valid users and 25 experts in this study. The questionnaire indicated 80% satisfaction rate for the motivational messages. According to game questionnaires, over 69% of the participants agreed that the games have good usability features, however, for questions related to mobility and gameplay heuristics, agreements were below 67%. The most accessed app sections were achieved benefits and the one with motivational messages. The experts described issues that could help to improve the application. CONCLUSIONS: The combination of questionnaires with expert reports allowed to identify several problems and possible corrections. Our study showed that motivational messages have a good satisfaction rate, although it is necessary to consider technical features of some mobile devices that may hinder message reception. Games have good usability and it's expected that the addition of difficulty levels and a better accessibility to the game menu could make them more attractive and increase its usage. Future development of mHealth apps based on gamification and motivational messages need to consider these factors for better user satisfaction and usability.


Assuntos
Comportamento do Consumidor , Aplicativos Móveis , Abandono do Hábito de Fumar , Adulto , Estudos de Coortes , Heurística Computacional , Feminino , Humanos , Masculino , Taiwan , Telemedicina , Adulto Jovem
17.
J Mech Behav Biomed Mater ; 98: 225-234, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31271979

RESUMO

Biomedical applications need tailor-made scaffolds that exhibit biomimetic mechanical properties. In this context, electrospinning has emerged as a technique with promising features for their production. However, the electrospun scaffolds mechanical behavior as a function of the microstructure and nanofiber properties is still poorly understood. Besides, multiscale constitutive modeling appears as a powerful design tool, not only able to characterize electrospun structures, but also to determine the fiber properties and scaffold microstructure that would achieve the objective response. With focus in this last aspect, we developed a multiscale constitutive model for nanofibrous structures that takes into account the material constitutive properties, scaffold microstructure, and nanofiber progressive recruitment. A statistical approach of the nanofibers tortuosity with a modified Gaussian distribution was adopted, which allowed for reproducing the scaffolds macroscopic nonlinear mechanical behavior. It was observed that such behavior arises even if the nanofibers response is considered as mechanically linear. Experimental data from pressure vs. diameter inflation tests of electrospun tubular scaffolds was used to validate the model. In addition, the influence of the microstructural parameters upon the macroscopic constitutive behavior was studied. Finally, the model parameters were adjusted to obtain a vascular graft able to reproduce the mechanical response of a target natural tissue. The current study presents a step towards understanding, characterizing, and optimizing the mechanical properties of nanofibrous biomaterials.


Assuntos
Fenômenos Mecânicos , Modelos Teóricos , Nanofibras , Alicerces Teciduais , Teste de Materiais
18.
Free Radic Biol Med ; 131: 59-71, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30472364

RESUMO

Uracil-DNA glycosylase (UNG) initiates the base excision repair pathway by excising uracil from DNA. We have previously shown that Trypanosoma brucei cells defective in UNG exhibit reduced infectivity thus demonstrating the relevance of this glycosylase for survival within the mammalian host. In the early steps of the immune response, nitric oxide (NO) is released by phagocytes, which in combination with oxygen radicals produce reactive nitrogen species (RNS). These species can react with DNA generating strand breaks and base modifications including deaminations. Since deaminated cytosines are the main substrate for UNG, we hypothesized that the glycosylase might confer protection towards nitrosative stress. Our work establishes the occurrence of genotoxic damage in Trypanosoma brucei upon exposure to NO in vitro and shows that deficient base excision repair results in increased levels of damage in DNA and a hypermutator phenotype. We also evaluate the incidence of DNA damage during infection in vivo and show that parasites recovered from mice exhibit higher levels of DNA strand breaks, base deamination and repair foci compared to cells cultured in vitro. Notably, the absence of UNG leads to reduced infectivity and enhanced DNA damage also in animal infections. By analysing mRNA and protein levels, we found that surviving UNG-KO trypanosomes highly express tryparedoxin peroxidase involved in trypanothione/tryparedoxin metabolism. These observations suggest that the immune response developed by the host enhances the activation of genes required to counteract oxidative stress and emphasize the importance of DNA repair pathways in the protection to genotoxic and oxidative stress in trypanosomes.


Assuntos
Reparo do DNA , DNA de Protozoário/genética , Óxido Nítrico/farmacologia , Proteínas de Protozoários/genética , Trypanosoma brucei brucei/genética , Uracila-DNA Glicosidase/genética , Animais , Dano ao DNA , DNA de Protozoário/imunologia , Feminino , Expressão Gênica , Genótipo , Glutationa/análogos & derivados , Glutationa/metabolismo , Interações Hospedeiro-Parasita , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Estresse Nitrosativo/genética , Parasitemia/imunologia , Parasitemia/metabolismo , Parasitemia/parasitologia , Peroxidases/genética , Peroxidases/metabolismo , Fenótipo , Proteínas de Protozoários/metabolismo , Espermidina/análogos & derivados , Espermidina/metabolismo , Tiorredoxinas/metabolismo , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei brucei/metabolismo , Trypanosoma brucei brucei/patogenicidade , Tripanossomíase/imunologia , Tripanossomíase/metabolismo , Tripanossomíase/parasitologia , Uracila-DNA Glicosidase/deficiência
19.
Science ; 362(6410): 86-91, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30166439

RESUMO

Mutations in the gene encoding dystrophin, a protein that maintains muscle integrity and function, cause Duchenne muscular dystrophy (DMD). The deltaE50-MD dog model of DMD harbors a mutation corresponding to a mutational "hotspot" in the human DMD gene. We used adeno-associated viruses to deliver CRISPR gene editing components to four dogs and examined dystrophin protein expression 6 weeks after intramuscular delivery (n = 2) or 8 weeks after systemic delivery (n = 2). After systemic delivery in skeletal muscle, dystrophin was restored to levels ranging from 3 to 90% of normal, depending on muscle type. In cardiac muscle, dystrophin levels in the dog receiving the highest dose reached 92% of normal. The treated dogs also showed improved muscle histology. These large-animal data support the concept that, with further development, gene editing approaches may prove clinically useful for the treatment of DMD.


Assuntos
Distrofina/genética , Edição de Genes/métodos , Distrofia Muscular de Duchenne/terapia , Adenoviridae , Animais , Sistemas CRISPR-Cas , Modelos Animais de Doenças , Cães , Distrofina/metabolismo , Feminino , Técnicas de Transferência de Genes , Masculino
20.
J Sci Food Agric ; 98(11): 4227-4236, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29406611

RESUMO

BACKGROUND: The main objectives of this study were to evaluate the use of near infrared spectroscopy (NIRS) to classify pork loins under different methods and cooking conditions, and to predict sensory attributes of this product. RESULTS: Samples were oven cooked at two temperatures (150 and 180 °C) for different times (45, 60 and 75 min) and confit cooked for different times (120, 180 and 240 min). All cooked loin samples were subjected to a Quantitative Descriptive Analysis by a trained panel. For classification, principal component analysis was performed based on the NIRS database, showing a good discrimination between loins samples subjected to different cooking conditions. Regarding prediction, a data mining technique (multiple linear regression) was applied on a database constructed with data from NIRS and sensory analysis. CONCLUSION: The correlation coefficient and the mean absolute error obtained suggest that the calculated prediction equations of this study are valid to predict the changes in the sensory attributes depending on the cooking method and conditions used for pork loins. © 2018 Society of Chemical Industry.


Assuntos
Culinária/métodos , Carne/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto , Animais , Feminino , Humanos , Masculino , Suínos , Paladar , Adulto Jovem
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