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mTORC2 controls glucose and lipid metabolism, but the mechanisms are unclear. Here, we show that conditionally deleting the essential mTORC2 subunit Rictor in murine brown adipocytes inhibits de novo lipid synthesis, promotes lipid catabolism and thermogenesis, and protects against diet-induced obesity and hepatic steatosis. AKT kinases are the canonical mTORC2 substrates; however, deleting Rictor in brown adipocytes appears to drive lipid catabolism by promoting FoxO1 deacetylation independently of AKT, and in a pathway distinct from its positive role in anabolic lipid synthesis. This facilitates FoxO1 nuclear retention, enhances lipid uptake and lipolysis, and potentiates UCP1 expression. We provide evidence that SIRT6 is the FoxO1 deacetylase suppressed by mTORC2 and show an endogenous interaction between SIRT6 and mTORC2 in both mouse and human cells. Our findings suggest a new paradigm of mTORC2 function filling an important gap in our understanding of this more mysterious mTOR complex.
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Adipócitos Marrons/metabolismo , Proteína Forkhead Box O1/metabolismo , Lipólise , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Sirtuínas/metabolismo , Adipócitos Marrons/citologia , Animais , Proteína Forkhead Box O1/genética , Células HEK293 , Células HeLa , Humanos , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Camundongos , Camundongos Transgênicos , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Sirtuínas/genéticaRESUMO
RNA import into mammalian mitochondria is considered essential for replication, transcription, and translation of the mitochondrial genome but the pathway(s) and factors that control this import are poorly understood. Previously, we localized polynucleotide phosphorylase (PNPASE), a 3' --> 5' exoribonuclease and poly-A polymerase, in the mitochondrial intermembrane space, a location lacking resident RNAs. Here, we show a new role for PNPASE in regulating the import of nuclear-encoded RNAs into the mitochondrial matrix. PNPASE reduction impaired mitochondrial RNA processing and polycistronic transcripts accumulated. Augmented import of RNase P, 5S rRNA, and MRP RNAs depended on PNPASE expression and PNPASE-imported RNA interactions were identified. PNPASE RNA processing and import activities were separable and a mitochondrial RNA targeting signal was isolated that enabled RNA import in a PNPASE-dependent manner. Combined, these data strongly support an unanticipated role for PNPASE in mediating the translocation of RNAs into mitochondria.
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Mitocôndrias/metabolismo , Polirribonucleotídeo Nucleotidiltransferase/metabolismo , RNA/metabolismo , Animais , Linhagem Celular , Técnicas de Inativação de Genes , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Polirribonucleotídeo Nucleotidiltransferase/genética , Processamento Pós-Transcricional do RNA , Ribonuclease P/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMO
BACKGROUND: Glofitamab is a bispecific antibody with promise for treating relapsed/refractory B-cell lymphoma according to a phase 1/2 clinical trial. This study examined its real-world effectiveness. METHODS: This was an investigator-initiated, multicenter retrospective study including 34 patients who had relapsed/refractory B-cell lymphomas after at least three prior lines of therapy and received glofitamab monotherapy in a compassionate use program in Taiwan between January 2021 and October 2022. RESULTS: At a median follow-up of 15.9 months, 56% of patients responded to glofitamab and 23% achieved complete remission. Response to the previous line of therapy significantly correlated with response to glofitamab (p = .020). Most responses were durable; only five out of the 19 responders had documented disease recurrence at the data cutoff date. The estimated progression-free survival (PFS) was 3.2 months, and the estimated 1-year PFS was 33% for the entire cohort. PFS was better for responders than nonresponders (median PFS, 16.9 vs. 1.8 months; 1-year PFS, 60% vs. 0%). Forty-three cytokine release syndrome (CRS) events were observed, three of which were grade 3; all were manageable without glofitamab discontinuation. No immune effector cell-associated neurotoxicity was reported. Among seven hepatitis B virus (HBV) carriers (six had antiviral prophylaxis) and 14 patients with remote HBV (four had antiviral prophylaxis), no HBV reactivation was observed. CONCLUSIONS: In this real-world cohort, glofitamab exhibited effectiveness comparable to trial results without excessive CRS or new safety issues. With appropriate prophylaxis, glofitamab-treated patients with chronic or remote HBV infection are unlikely to experience virus reactivation.
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Anticorpos Biespecíficos , Linfoma de Células B , Terapia de Salvação , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Linfoma de Células B/tratamento farmacológico , Terapia de Salvação/métodos , Estudos Retrospectivos , Adulto , Taiwan , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/efeitos adversos , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Recidiva Local de Neoplasia/tratamento farmacológico , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversosRESUMO
Germ cells in Drosophila melanogaster are specified maternally shortly after fertilization and are transcriptionally quiescent until their zygotic genome is activated to sustain further development. To understand the molecular basis of this process, we analyzed the progressing transcriptomes of early male and female germ cells at the single-cell level between germline specification and coalescence with somatic gonadal cells. Our data comprehensively cover zygotic activation in the germline genome, and analyses on genes that exhibit germline-restricted expression reveal that polymerase pausing and differential RNA stability are important mechanisms that establish gene expression differences between the germline and soma. In addition, we observe an immediate bifurcation between the male and female germ cells as zygotic transcription begins. The main difference between the two sexes is an elevation in X Chromosome expression in females relative to males, signifying incomplete dosage compensation, with a few select genes exhibiting even higher expression increases. These indicate that the male program is the default mode in the germline that is driven to female development with a second X Chromosome.
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Proteínas de Drosophila , Drosophila , Animais , Mecanismo Genético de Compensação de Dose , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Masculino , Diferenciação SexualRESUMO
In this study, our objective was to assess the performance of two deep learning-based hippocampal segmentation methods, SynthSeg and TigerBx, which are readily available to the public. We contrasted their performance with that of two established techniques, FreeSurfer-Aseg and FSL-FIRST, using three-dimensional T1-weighted MRI scans (n = 1447) procured from public databases. Our evaluation focused on the accuracy and reproducibility of these tools in estimating hippocampal volume. The findings suggest that both SynthSeg and TigerBx are on a par with Aseg and FIRST in terms of segmentation accuracy and reproducibility, but offer a significant advantage in processing speed, generating results in less than 1 min compared with several minutes to hours for the latter tools. In terms of Alzheimer's disease classification based on the hippocampal atrophy rate, SynthSeg and TigerBx exhibited superior performance. In conclusion, we evaluated the capabilities of two deep learning-based segmentation techniques. The results underscore their potential value in clinical and research environments, particularly when investigating neurological conditions associated with hippocampal structures.
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Aprendizado Profundo , Hipocampo , Imageamento por Ressonância Magnética , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Feminino , Tamanho do Órgão , Reprodutibilidade dos Testes , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Pessoa de Meia-Idade , Processamento de Imagem Assistida por Computador/métodos , AdultoRESUMO
BACKGROUND: The modified Look-Locker inversion recovery (MOLLI) sequence is commonly used for myocardial T1 mapping. However, it acquires images with different inversion times, which causes difficulty in motion correction for respiratory-induced misregistration to a given target image. HYPOTHESIS: Using a generative adversarial network (GAN) to produce virtual MOLLI images with consistent heart positions can reduce respiratory-induced misregistration of MOLLI datasets. STUDY TYPE: Retrospective. POPULATION: 1071 MOLLI datasets from 392 human participants. FIELD STRENGTH/SEQUENCE: Modified Look-Locker inversion recovery sequence at 3 T. ASSESSMENT: A GAN model with a single inversion time image as input was trained to generate virtual MOLLI target (VMT) images at different inversion times which were subsequently used in an image registration algorithm. Four VMT models were investigated and the best performing model compared with the standard vendor-provided motion correction (MOCO) technique. STATISTICAL TESTS: The effectiveness of the motion correction technique was assessed using the fitting quality index (FQI), mutual information (MI), and Dice coefficients of motion-corrected images, plus subjective quality evaluation of T1 maps by three independent readers using Likert score. Wilcoxon signed-rank test with Bonferroni correction for multiple comparison. Significance levels were defined as P < 0.01 for highly significant differences and P < 0.05 for significant differences. RESULTS: The best performing VMT model with iterative registration demonstrated significantly better performance (FQI 0.88 ± 0.03, MI 1.78 ± 0.20, Dice 0.84 ± 0.23, quality score 2.26 ± 0.95) compared to other approaches, including the vendor-provided MOCO method (FQI 0.86 ± 0.04, MI 1.69 ± 0.25, Dice 0.80 ± 0.27, quality score 2.16 ± 1.01). DATA CONCLUSION: Our GAN model generating VMT images improved motion correction, which may assist reliable T1 mapping in the presence of respiratory motion. Its robust performance, even with considerable respiratory-induced heart displacements, may be beneficial for patients with difficulties in breath-holding. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 1.
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BACKGROUND Clinical training for allied health trainees (AHTs) and postgraduate-year (PGY) doctors needed to go online during the outbreak of coronavirus disease 2019 (COVID-19), which may have caused academic stress and consequent outcomes among this cohort. MATERIAL AND METHODS To evaluate academic-related stress, clinical confidence, psychological distress, and insomnia, an online survey-based study was conducted among Taiwanese AHTs and PGY doctors between July and December, 2022, during the COVID-19 pandemic. The survey included the 21-item Depression, Anxiety, and Stress Scale (DASS-21), the Insomnia Severity Index (ISI), and self-designed questions. It was distributed using convenience sampling and snowball sampling and was completed by 522 participants. RESULTS Structural equational modelling showed that academic stress was negatively associated with clinical confidence (standardized coefficient [ß]=-0.382, p<0.001). Clinical confidence was negatively associated with psychological distress (ß=-0.397, p<0.001), which was associated with insomnia (ß=0.648, p<0.001). Additionally, clinical confidence and psychological distress were the significant mediators. Results indicated that higher academic stress was associated with higher level of insomnia via the mediation of clinical confidence and psychological distress. CONCLUSIONS Academic stress related to changes in clinical training may have led to insomnia among AHTs and PGY doctors during the pandemic. Factors to reduce academic stress should be investigated to promote good mental health while providing sufficient clinical training, especially during events that can cause increased stress (eg, epidemics, pandemics).
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COVID-19 , Distúrbios do Início e da Manutenção do Sono , Estresse Psicológico , Ideação Suicida , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Taiwan/epidemiologia , Masculino , Feminino , Adulto , Estresse Psicológico/psicologia , Inquéritos e Questionários , SARS-CoV-2 , Ansiedade/psicologia , Pandemias , Depressão/psicologia , Corpo Clínico Hospitalar/psicologiaRESUMO
BACKGROUND: Based on a longitudinal cohort design, the aim of this study was to investigate whether individual-based 18F fluorodeoxyglucose positron emission tomography (18F-FDG-PET) regional signals can predict dementia conversion in patients with mild cognitive impairment (MCI). METHODS: We included 44 MCI converters (MCI-C), 38 non-converters (MCI-NC), 42 patients with Alzheimer's disease with dementia, and 40 cognitively normal controls. Data from annual cognitive measurements, 3D T1 magnetic resonance imaging (MRI) scans, and 18F-FDG-PET scans were used for outcome analysis. An individual-based FDG-PET approach was applied using seven volumes of interest (VOIs), Z transformed using a normal FDG-PET template. Hypometabolism was defined as a Z score < -2 of regional standard uptake value ratio. For the longitudinal cognitive test scores, generalized estimating equations were used. A linear mixed-effects model was used to compare the temporal impact of cortical hypometabolism and cortical thickness degeneration. RESULTS: The clinical follow-up period was 6.6 ± 3.8 years (range 3.1 to 16.0 years). The trend of cognitive decline could differentiate MCI-C from MCI-NC after 3 years of follow-up. In the baseline 18F-FDG-PET scan of the patients with MCI, medial temporal lobe (MTL; 94.7% sensitivity, 80.5% specificity) and posterior cingulate cortex (PCC; 89.5% sensitivity, 73.1% specificity) hypometabolism predicted conversion with high accuracy. 18F-FDG-PET hypometabolism preceded dementia conversion at an interval of 3.70 ± 1.68 years and was earlier than volumetric changes, with the exception of the MTL. CONCLUSIONS: Our finding supports the use of individual-based 18F-FDG-PET analysis to predict MCI conversion to dementia. Reduced FDG-PET metabolism in the MTL and PCC were strongly associated with future cognitive decline in the MCI-C group. Changes in 18F-FDG-PET occurred 1 to 8 years prior to conversion to dementia. Progressive hypometabolism in the PCC, precuneus and lateral temporal lobe, but not MTL, preceded MRI findings at the MCI stage.
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Doença de Alzheimer , Disfunção Cognitiva , Humanos , Fluordesoxiglucose F18 , Progressão da Doença , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/metabolismoRESUMO
PURPOSE: We aimed to explore the clinical outcomes and prognostic factors for PTCL-NOS patients in the real world. METHODS: Clinical data were retrospectively collected from adult patients with PTCL-NOS treated at a single center in Taiwan. RESULTS: 104 PTCL-NOS patients with a median age of 53.0 years were enrolled. Patients with the International Prognostic Index (IPI) or prognostic index for peripheral T-cell lymphoma (PIT) scores of zero had a longer overall survival (OS) and progression free survival (PFS), while patients with IPI or PIT scores ≥1 did poorly. For patients who are eligible for transplantation, the use of pralatrexate as salvage chemotherapy has shown better OS (2-year OS 83.3% vs. 24.4%, P = 0.011) compared to patients who did not. By multivariate analysis, age >60 years, male, B symptoms, ECOG >1, lung involvement, and thrombocytopenia were independent adverse factors for OS. Incorporating factors in multivariate analysis, we established a novel predictive index for PTCL-NOS which efficiently stratifies patients into low (0-1 factor), intermediate-1 (2 factors), intermediate-2 (3 factors), and high risk (4-6 factors) groups with 2-year OS rates of 81.5%, 32.9%, 8.8%, and 0%, respectively (P < 0.001). CONCLUSION: PTCL-NOS patients have a dismal prognosis in Taiwan. Novel agents may improve the outcomes of PTCL-NOS patients. The usefulness of the novel prognostic index for PTCL-NOS needs further validation.
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Linfoma de Células T Periférico , Humanos , Masculino , Pessoa de Meia-Idade , Linfoma de Células T Periférico/tratamento farmacológico , Intervalo Livre de Progressão , Estudos Retrospectivos , Resultado do Tratamento , População do Leste AsiáticoRESUMO
BACKGROUND: Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is rare, with a high incidence of central nervous system (CNS) relapse. This study aims to investigate clinical characteristics, prognostic factors, and outcomes in Taiwanese PB-DLBCL patients and review the literature on PB-DLBCL. METHODS: Thirty-one PB-DLBCL patients diagnosed between 2000 and 2021 were retrospectively enrolled for analysis. RESULTS: The median age was 49 (range 26-79) years. The complete remission (CR) rate was 90.3%. Nine (90%) of the ten patients who experienced relapse had CNS involvement at the time of relapse. The one-year, two-year, and five-year progression-free survival (PFS) rates were 86.6% (95% confidence interval [CI] 75.2-99.8), 75.8% (95% CI 61.6-93.2), and 45.1% (95% CI 29.5-68.9), respectively. The five-year overall survival (OS) rate was 64.1% (95 % CI 48.4-85.0). A stage-modified International Prognostic Index (mIPI) less than two (five-year PFS rate 52.5% vs. 17.1%, P = 0.02) and the achievement of CR after first-line treatment (two-year PFS rate 80.3% vs. 33.3%, P < 0.001) were significant favorable prognostic factors for PFS. Hematopoietic stem cell transplantation (HSCT) after the first relapse was associated with significantly improved post-relapse OS (five-year OS rate 85.7% vs. 20.0%, P = 0.02) and PFS (five-year PFS rate 85.7% vs. 20.0%, P = 0.02). CONCLUSION: Patients with low-risk mIPI scores, CR after first-line treatment, and those who underwent HSCT after the first relapse had significantly better survival. Intrathecal chemotherapy conferred no benefit in preventing CNS relapse. Further research is needed to assess frontline HSCT's effectiveness in improving outcomes and preventing CNS relapses in PB-DLBCL patients.
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PURPOSE: How to factor both tumor burden and oncogenic genomic mutations as variables to predict the outcome of endocrine-based therapy (ET) in ER-positive/HER2-negative metastatic breast cancer patients (MBC) remains to be explored. METHOD: Blood samples prospectively collected from 163 ER-positive/HER2-negative female MBC patients, before ET, were used for cell-free tumor DNA (cfDNA) analysis. cfDNA was subjected to next-generation sequencing (NGS) to interrogate oncogenic PIK3CA hotspot and TP53 DNA-binding domain (DBD) mutations, including single nucleotide variants (SNVs) or small insertions and deletions (InDels). The variant calling threshold was set at 0.5%. Progression-free survival (PFS) was measured from the start of the ET treatment to the time of disease progression of the same treatment regimen. RESULTS: Overall, the median PFS was 8.3 months (95% CI 5.7-11.1 months). The median cfDNA was 38.5 ng (range 4.4-1935 ng). The proportion of patients with PIK3CA and TP53 alterations were 25.1 and 15.3%, respectively. Patients with high total cfDNA (HR 1.74, p = 0.003), PIK3CA mutation (HR 1.74, p = 0.007), and TP53 mutation (HR 1.64, p = 0.047) in liquid biopsy conferred worse outcome after ET. Even for patients with low tumor burden, the detrimental effect of PIK3CA or TP53 mutation remained significant (p < 0.001). For patients with either PIK3CA (p < 0.001) or TP53 mutation (p = 0.004), there was significant positive correlation between allele frequency (AF) and total cfDNA. CONCLUSION: After adjustment of cfDNA level, PIK3CA and TP53 mutations observed in liquid biopsy exerted detrimental effects on the outcome of ET-based regimens. The AF of PIK3CA or TP53 may be a surrogate marker for PFS.
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Neoplasias da Mama , Ácidos Nucleicos Livres , DNA Tumoral Circulante , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , Mutação , Resultado do Tratamento , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteína Supressora de Tumor p53/genéticaRESUMO
BACKGROUND: To evaluate the effect of the weighting of input imaging combo and ADC threshold on the performance of the U-Net and to find an optimized input imaging combo and ADC threshold in segmenting acute ischemic stroke (AIS) lesion. METHODS: This study retrospectively enrolled a total of 212 patients having AIS. Four combos, including ADC-ADC-ADC (AAA), DWI-ADC-ADC (DAA), DWI-DWI-ADC (DDA), and DWI-DWI-DWI (DDD), were used as input images, respectively. Three ADC thresholds including 0.6, 0.8 and 1.8 × 10-3 mm2/s were applied. Dice similarity coefficient (DSC) was used to evaluate the segmentation performance of U-Nets. Nonparametric Kruskal-Wallis test with Tukey-Kramer post-hoc tests were used for comparison. A p < .05 was considered statistically significant. RESULTS: The DSC significantly varied among different combos of images and different ADC thresholds. Hybrid U-Nets outperformed uniform U-Nets at ADC thresholds of 0.6 × 10-3 mm2/s and 0.8 × 10-3 mm2/s (p < .001). The U-Net with imaging combo of DDD had segmentation performance similar to hybrid U-Nets at an ADC threshold of 1.8 × 10-3 mm2/s (p = .062 to 1). The U-Net using the imaging combo of DAA at the ADC threshold of 0.6 × 10-3 mm2/s achieved the highest DSC in the segmentation of AIS lesion. CONCLUSIONS: The segmentation performance of U-Net for AIS varies among the input imaging combos and ADC thresholds. The U-Net is optimized by choosing the imaging combo of DAA at an ADC threshold of 0.6 × 10-3 mm2/s in segmentating AIS lesion with highest DSC. KEY POINTS: ⢠Segmentation performance of U-Net for AIS differs among input imaging combos. ⢠Segmentation performance of U-Net for AIS differs among ADC thresholds. ⢠U-Net is optimized using DAA with ADC = 0.6 × 10-3 mm2/s.
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AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagemRESUMO
PURPOSE: New drug development and delivery approaches result in an ever-increasing demand for tailored microparticles with defined sizes and structures. Inkjet printing technologies could be promising new processes to engineer particles with defined characteristics, as they are created to precisely deliver liquid droplets with high uniformity. METHODS: D-mannitol was used as a model compound alone or co-processed with the pore former agent ammonium bicarbonate, and the polymer polyethylene glycol 200. Firstly, a drop shape analyzer was used to characterize and understand ink/substrate interactions, evaporation, and solidification kinetics. Consequently, the process was transferred to a laboratory-scale inkjet printer and the resulting particles collected, characterized and compared to others obtained via an industrial standard technique. RESULTS: The droplet shape analysis allowed to understand how 3D structures are formed and helped define the formulation and process parameters for inkjet printing. By adjusting the drop number and process waveform, spherical particles with a mean size of approximately 100 µm were obtained. The addition of pore former and polymer allowed to tailor the crystallization kinetics, resulting in particles with a different surface (i.e., spike-like surface) and bulk (e.g. porous and non-porous) structure. CONCLUSION: The workflow described enabled the production of 3D structures via inkjet printing, demonstrating that this technique can be a promising approach to engineer microparticles.
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Polímeros , Fluxo de TrabalhoRESUMO
Cannabinoid receptor 1 (CB1) is a G protein-coupled receptor and a therapeutic target for metabolic disorders. Numerous CB1 antagonists have been developed, but their functional selectivities and bias towards G protein or ß-arrestin signaling have not been systemically characterized. In this study, we analyzed the binding affinities and downstream signaling of two series of pyrazole derivatives bearing 1-aminopiperidine (Series I) or 4-aminothiomorpholine 1,1-dioxide (Series II) moieties, as well as the well-known CB1 antagonists rimonabant and taranabant. Analyses of the results for the Series I and II derivatives showed that minor structure modifications to their functional groups and especially the incorporation of 1-aminopiperidine or 4-aminothiomorpholine 1,1-dioxide motifs can profoundly affect their bias toward G protein or ß-arrestin signaling, and that their binding affinity and functional activity can be disassociated. Docking and molecular dynamics simulations revealed that the binding modes of Series I and II antagonists differed primarily in that Series I antagonists formed an additional hydrogen bond with the receptor, whereas those in Series II formed a water bridge.
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Antagonistas de Receptores de Canabinoides , Proteínas de Ligação ao GTP , Antagonistas de Receptores de Canabinoides/farmacologia , Antagonistas de Receptores de Canabinoides/metabolismo , Rimonabanto , beta-Arrestinas/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Receptores de Canabinoides/metabolismoRESUMO
BACKGROUND: The diffusion tensor imaging analysis along the perivascular space (ALPS)-index can be used to model the glymphatic system in vivo. AIM: This study explores putative mechanisms between prediction of ALPS-index and cognitive outcomes in young-onset Alzheimer's disease (YOAD) and age-matched controls (CTLs) and analyzes whether the link was mediated by the integrity of ALPS-index-anchored cerebral gray matter (GM). METHODS: We enrolled 130 patients with YOAD and 137 CTLs. All participants underwent three-dimensional T1 -weighted MRI, diffusion tensor imaging and cognitive tests. We constructed GM regions correlated with the ALPS-index in the YOAD and CTL groups. For the GM regions significantly correlated with the ALPS-index and cognitive measures, we extracted a 4-mm radius sphere. In the YOAD and CTL groups, we used mediator analysis to explore the ALPS-index as predictor, GM partitions as mediators, and significant cognitive test scores as outcomes. RESULTS: Patient group had significantly lower ALPS-index. The ALPS-index was associated with GM volume in the cerebellar gray, dorsolateral prefrontal, thalamus, superior frontal, amygdala and hippocampus, and these coherent regions coincided with those showing GM atrophy in the YOAD group. Mediation analysis of the YOAD group suggested that the relationships between the ALPS-index and cognitive performance were fully mediated by the integrity of ALPS-index coherent GM areas. DISCUSSION: Reserved GM mediates the link between the glymphatic system and cognition. Our findings suggest that GM integrity rather than the glymphatic system could serve as a direct cognitive test scores predictor in patients with YOAD.
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Doença de Alzheimer , Sistema Glinfático , Humanos , Substância Cinzenta/diagnóstico por imagem , Imagem de Tensor de Difusão , Doença de Alzheimer/diagnóstico por imagem , Sistema Glinfático/diagnóstico por imagem , Córtex CerebralRESUMO
Mitochondria (MITO) and peroxisomes (PEXO) are the major organelles involved in the oxidative metabolism of cells, but detailed examination of their dynamics and functional adaptations during skeletal muscle (SKM) development (myogenesis) is still lacking. In this study, we found that during myogenesis, MITO DNA, ROS level, and redox ratio increased in myotubes, but the membrane potential (Δψm) and ATP content reduced, implying that the MITO efficiency might reduce during myogenesis. The PEXO number and density both increased during myogenesis, which probably resulted from the accumulation and increased biogenesis of PEXO. The expression of PEXO biogenesis factors was induced during myogenesis in vitro and in utero, and their promoters were also activated by MyoD. Knockdown of the biogenesis factors Pex3 repressed not only the PEXO density and functions but also the levels of MITO genes and functions, suggesting a close coupling between PEXO biogenesis and MITO functions. Surprisingly, Pex3 knockdown by the CRISPRi system repressed myogenic differentiation, indicating critical involvement of PEXO biogenesis in myogenesis. Taken together, these observations suggest that the dynamics and functions of both MITO and PEXO are coupled with each other and with the metabolic changes that occur during myogenesis, and these metabolic couplings are critical to myogenesis.
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Fibras Musculares Esqueléticas , Peroxissomos , Peroxissomos/metabolismo , Diferenciação Celular/genética , Fibras Musculares Esqueléticas/metabolismo , Mitocôndrias/metabolismo , Desenvolvimento Muscular/genética , Músculo Esquelético/metabolismoRESUMO
STATEMENT OF PROBLEM: The properties of commercially pure titanium are better than those of cobalt chromium alloys in various ways. However, casting pure titanium is challenging because of its high melting point and chemical reactivity. Because of excellent mechanical strength, a titanium alloy, Ti-6Al-4V, has been commonly adopted, but the aluminum and vanadium ions released may be cytotoxic. PURPOSE: The purpose of the present study was to evaluate a new titanium alloy, Ti-7.5Mo, developed by the National Cheng Kung University for casting removable denture frameworks. The casting success rate, porosity, and guide plane or rest fit were compared among frameworks cast with Ti-7.5Mo alloy and pure titanium for 3 types of edentulism. MATERIAL AND METHODS: Ti-7.5Mo alloy and pure titanium were used to cast frameworks for Kennedy Class I and II and completely edentulous conditions, with 5 frameworks for each condition. Wax patterns of the frameworks were designed and fabricated by using computer-aided design and computer-aided manufacture (CAD-CAM) technology to ensure their geometrical consistency. They were then invested with aluminum oxide-based material and cast. The castings were examined with microcomputed tomography (µCT) for porosity, and fit was evaluated from the thickness of a vinyl polyether silicone material at the guide plane or the rest by using an optical microscope. The casting was determined to be successful if the frameworks were complete. The porosity and fit were statistically evaluated by using 2-way ANOVA (α=.05). RESULTS: Using pure titanium, the casting success rate was 80%, with only 64% of the major connectors in the deficient castings being complete. The µCT images showed that the percentage of casting defects in Ti-7.5Mo castings was one-third of the pure titanium castings. Furthermore, internal voids were detected in the clasps of the pure titanium castings, while the Ti-7.5Mo castings had few defects in the minor connectors and no radiographically detectable defects in the clasps. The fit analysis demonstrated smaller gaps over both guide planes and rests in the Ti-7.5Mo castings. CONCLUSIONS: Ti-7.5Mo alloy had better castability than pure titanium. Based on the results, Ti-7.5Mo alloy is suitable for dental casting and may provide better performance.
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Versican is a chondroitin sulfate proteoglycan (CSPG), which deposits in perineurium as a physical barrier and prevents the growth of axons out of the fascial boundary. Several studies have indicated that the chondroitin sulfate (CS) chains on versican have several possible functions beyond the physical barrier, including the ability to stabilize versican core protein in the extracellular matrix. As chondroitin sulfate synthase 1 (Chsy1) is a crucial enzyme for CS elongation, we hypothesized that in vivo knockdown of Chsy1 at peripheral nerve lesion site may decrease CS and versican accumulation, and result in accelerating neurite regeneration. In the present study, end-to-side neurorrhaphy (ESN) in Wistar rats was used as an in vivo model of peripheral nerve injury to evaluate nerve regeneration after surgical intervention. The distribution and expression of versican and Chsy1 in regenerating axons after ESN was studied using confocal microscopy and western blotting. Chsy1 was silenced at the nerve lesion (surgical) site using in vivo siRNA transfection. The results indicated that Chsy1 was successfully silenced in nerve tissue, and its downregulation was associated with functional recovery of compound muscle action potential. Silencing of Chsy1 also decreased the accumulation of versican core protein, suggesting that transient treating of Chsy1-siRNA may be an alternative and an effective strategy to promote injured peripheral nerve regeneration.
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Sulfatos de Condroitina , Versicanas , Ratos , Animais , Versicanas/genética , Sulfatos de Condroitina/farmacologia , Ratos Wistar , Axônios/metabolismo , Regeneração Nervosa , RNA Interferente Pequeno/farmacologiaRESUMO
We developed a new questionnaire-the Sarcopenia Knowledge Questionnaire (SKQ)-to evaluate the level of awareness about sarcopenia among older adults and tested the reliability and validity of this tool. A total of 293 older adults completed the questionnaire. The SKQ comprises three domains including 23 items: screening and diagnosis (10 items), sarcopenia outcomes (7 items), and lifestyle factors (6 items). The Cronbach's α value was 0.969, which indicated excellent internal consistency. The SKQ correlated well with the Mandarin Multidimensional Health Literacy Questionnaire (r = 0.511; p < 0.001), confirming its moderate convergent validity. The absolute values of the critical ratio ranged from 9.90 to 25.82 (p < 0.001), indicating satisfactory item discrimination. Thus, the SKQ appears to be a valid and reliable instrument for evaluating the knowledge of older adults about sarcopenia.
Assuntos
Letramento em Saúde , Sarcopenia , Humanos , Idoso , Sarcopenia/diagnóstico , Reprodutibilidade dos Testes , Inquéritos e Questionários , Estilo de Vida , PsicometriaRESUMO
Purpose: The cervicovaginal microbiota is essential for maintaining the health of the female reproductive tract. However, whether cervicovaginal microbiota status prior to frozen embryo transfer (FET) associates with pregnancy outcomes is largely unexplored. Methods: Cervical mucus from 29 women who had undergone FET was collected. Microbial composition was analyzed using 16 S rRNA gene sequence to assess the correlation to the pregnancy outcomes. Results: CST-categorized Lactobacillus was the most dominant (41.71%) in the pregnant group, while CST-IV-based and BV-related Gardnerella (34.96%) prevailed in the non-pregnant group. The average abundance of Gardnerella compared non-pregnant to pregnant women was the highest (34.96% vs. 4.22%, p = 0.0015) among other CST-IV indicator bacteria. Multivariate analysis revealed that CST-IV-related bacteria have a significantly adverse effect on ongoing pregnancy outcomes (odds ratio, 0.083; 95% confidence index, 0.012-0.589, p = 0.013*). Conclusions: The study found that the CST-IV microbiota, with significantly increasing Gardnerella and the loss of Lactobacilli as the dominant bacteria, can potentially contribute to pregnancy failure. Therefore, dysbiotic microbiota may be a risk factor in women undergoing FET. Assessing the health of the cervicovaginal microbiota prior to FET would enable couples to make a more thoughtful decision on the timing and might improve pregnancy outcomes.