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1.
Cell ; 175(7): 1756-1768.e17, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30550785

RESUMO

Irisin is secreted by muscle, increases with exercise, and mediates certain favorable effects of physical activity. In particular, irisin has been shown to have beneficial effects in adipose tissues, brain, and bone. However, the skeletal response to exercise is less clear, and the receptor for irisin has not been identified. Here we show that irisin binds to proteins of the αV class of integrins, and biophysical studies identify interacting surfaces between irisin and αV/ß5 integrin. Chemical inhibition of the αV integrins blocks signaling and function by irisin in osteocytes and fat cells. Irisin increases both osteocytic survival and production of sclerostin, a local modulator of bone remodeling. Genetic ablation of FNDC5 (or irisin) completely blocks osteocytic osteolysis induced by ovariectomy, preventing bone loss and supporting an important role of irisin in skeletal remodeling. Identification of the irisin receptor should greatly facilitate our understanding of irisin's function in exercise and human health.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Remodelação Óssea , Fibronectinas/metabolismo , Integrina alfaV/metabolismo , Osteócitos/metabolismo , Osteólise/metabolismo , Adipócitos/patologia , Animais , Linhagem Celular Tumoral , Feminino , Fibronectinas/genética , Células HEK293 , Humanos , Integrina alfaV/genética , Camundongos , Osteócitos/patologia , Osteólise/genética
3.
Nature ; 621(7977): 138-145, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37587337

RESUMO

Maintaining body temperature is calorically expensive for endothermic animals1. Mammals eat more in the cold to compensate for energy expenditure2, but the neural mechanism underlying this coupling is not well understood. Through behavioural and metabolic analyses, we found that mice dynamically switch between energy-conservation and food-seeking states in the cold, the latter of which are primarily driven by energy expenditure rather than the sensation of cold. To identify the neural mechanisms underlying cold-induced food seeking, we used whole-brain c-Fos mapping and found that the xiphoid (Xi), a small nucleus in the midline thalamus, was selectively activated by prolonged cold associated with elevated energy expenditure but not with acute cold exposure. In vivo calcium imaging showed that Xi activity correlates with food-seeking episodes under cold conditions. Using activity-dependent viral strategies, we found that optogenetic and chemogenetic stimulation of cold-activated Xi neurons selectively recapitulated food seeking under cold conditions whereas their inhibition suppressed it. Mechanistically, Xi encodes a context-dependent valence switch that promotes food-seeking behaviours under cold but not warm conditions. Furthermore, these behaviours are mediated by a Xi-to-nucleus accumbens projection. Our results establish Xi as a key region in the control of cold-induced feeding, which is an important mechanism in the maintenance of energy homeostasis in endothermic animals.


Assuntos
Temperatura Corporal , Temperatura Baixa , Comportamento Alimentar , Tálamo , Animais , Camundongos , Temperatura Corporal/fisiologia , Mapeamento Encefálico , Cálcio/metabolismo , Comportamento Alimentar/fisiologia , Metabolismo Energético/fisiologia , Tálamo/anatomia & histologia , Tálamo/citologia , Tálamo/fisiologia , Optogenética , Neurônios/metabolismo , Núcleo Accumbens/citologia , Núcleo Accumbens/fisiologia , Homeostase/fisiologia , Termogênese/fisiologia
4.
Nature ; 596(7870): 119-125, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34290406

RESUMO

Interactions between T cell receptors (TCRs) and their cognate tumour antigens are central to antitumour immune responses1-3; however, the relationship between phenotypic characteristics and TCR properties is not well elucidated. Here we show, by linking the antigenic specificity of TCRs and the cellular phenotype of melanoma-infiltrating lymphocytes at single-cell resolution, that tumour specificity shapes the expression state of intratumoural CD8+ T cells. Non-tumour-reactive T cells were enriched for viral specificities and exhibited a non-exhausted memory phenotype, whereas melanoma-reactive lymphocytes predominantly displayed an exhausted state that encompassed diverse levels of differentiation but rarely acquired memory properties. These exhausted phenotypes were observed both among clonotypes specific for public overexpressed melanoma antigens (shared across different tumours) or personal neoantigens (specific for each tumour). The recognition of such tumour antigens was provided by TCRs with avidities inversely related to the abundance of cognate targets in melanoma cells and proportional to the binding affinity of peptide-human leukocyte antigen (HLA) complexes. The persistence of TCR clonotypes in peripheral blood was negatively affected by the level of intratumoural exhaustion, and increased in patients with a poor response to immune checkpoint blockade, consistent with chronic stimulation mediated by residual tumour antigens. By revealing how the quality and quantity of tumour antigens drive the features of T cell responses within the tumour microenvironment, we gain insights into the properties of the anti-melanoma TCR repertoire.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Melanoma/imunologia , Especificidade por Substrato/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Regulação da Expressão Gênica , Humanos , Linfócitos do Interstício Tumoral/imunologia , Melanoma/sangue , Fenótipo , Receptores de Antígenos de Linfócitos T/imunologia , Análise de Célula Única , Transcriptoma/genética , Microambiente Tumoral
5.
Proc Natl Acad Sci U S A ; 120(44): e2313825120, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37871217

RESUMO

Lipoprotein lipase (LPL), the enzyme that carries out the lipolytic processing of triglyceride-rich lipoproteins (TRLs), is synthesized by adipocytes and myocytes and secreted into the interstitial spaces. The LPL is then bound by GPIHBP1, a GPI-anchored protein of endothelial cells (ECs), and transported across ECs to the capillary lumen. The assumption has been that the LPL that is moved into capillaries remains attached to GPIHBP1 and that GPIHBP1 serves as a platform for TRL processing. In the current studies, we examined the validity of that assumption. We found that an LPL-specific monoclonal antibody (mAb), 88B8, which lacks the ability to detect GPIHBP1-bound LPL, binds avidly to LPL within capillaries. We further demonstrated, by confocal microscopy, immunogold electron microscopy, and nanoscale secondary ion mass spectrometry analyses, that the LPL detected by mAb 88B8 is located within the EC glycocalyx, distant from the GPIHBP1 on the EC plasma membrane. The LPL within the glycocalyx mediates the margination of TRLs along capillaries and is active in TRL processing, resulting in the delivery of lipoprotein-derived lipids to immediately adjacent parenchymal cells. Thus, the LPL that GPIHBP1 transports into capillaries can detach and move into the EC glycocalyx, where it functions in the intravascular processing of TRLs.


Assuntos
Lipase Lipoproteica , Receptores de Lipoproteínas , Anticorpos Monoclonais/metabolismo , Capilares/metabolismo , Células Endoteliais/metabolismo , Glicocálix/metabolismo , Lipase Lipoproteica/metabolismo , Lipoproteínas/metabolismo , Receptores de Lipoproteínas/metabolismo , Triglicerídeos/metabolismo , Humanos , Animais
6.
Nature ; 565(7738): 234-239, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30568305

RESUMO

Neoantigens, which are derived from tumour-specific protein-coding mutations, are exempt from central tolerance, can generate robust immune responses1,2 and can function as bona fide antigens that facilitate tumour rejection3. Here we demonstrate that a strategy that uses multi-epitope, personalized neoantigen vaccination, which has previously been tested in patients with high-risk melanoma4-6, is feasible for tumours such as glioblastoma, which typically have a relatively low mutation load1,7 and an immunologically 'cold' tumour microenvironment8. We used personalized neoantigen-targeting vaccines to immunize patients newly diagnosed with glioblastoma following surgical resection and conventional radiotherapy in a phase I/Ib study. Patients who did not receive dexamethasone-a highly potent corticosteroid that is frequently prescribed to treat cerebral oedema in patients with glioblastoma-generated circulating polyfunctional neoantigen-specific CD4+ and CD8+ T cell responses that were enriched in a memory phenotype and showed an increase in the number of tumour-infiltrating T cells. Using single-cell T cell receptor analysis, we provide evidence that neoantigen-specific T cells from the peripheral blood can migrate into an intracranial glioblastoma tumour. Neoantigen-targeting vaccines thus have the potential to favourably alter the immune milieu of glioblastoma.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Glioblastoma/imunologia , Glioblastoma/terapia , Linfócitos T/imunologia , Adulto , Idoso , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dexametasona/administração & dosagem , Glioblastoma/diagnóstico , Glioblastoma/genética , Humanos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Supressoras de Tumor/genética , Adulto Jovem
7.
J Am Chem Soc ; 146(23): 15701-15717, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38819106

RESUMO

Polar and chiral crystal symmetries confer a variety of potentially useful functionalities upon solids by coupling otherwise noninteracting mechanical, electronic, optical, and magnetic degrees of freedom. We describe two phases of the 3D perovskite, CsSnBr3, which emerge below 85 K due to the formation of Sn(II) lone pairs and their interaction with extant octahedral tilts. Phase II (77 K < T < 85 K, space group P21/m) exhibits ferroaxial order driven by a noncollinear pattern of lone pair-driven distortions within the plane normal to the unique octahedral tilt axis, preserving the inversion symmetry observed at higher temperatures. Phase I (T < 77 K, space group P21) additionally exhibits ferroelectric order due to distortions along the unique tilt axis, breaking both inversion and mirror symmetries. This polar and chiral phase exhibits second harmonic generation from the bulk and pronounced electrostriction and negative thermal expansion along the polar axis (Q22 ≈ 1.1 m4 C-2; αb = -7.8 × 10-5 K-1) through the onset of polarization. The structures of phases I and II were predicted by recursively following harmonic phonon instabilities to generate a tree of candidate structures and subsequently corroborated by synchrotron X-ray powder diffraction and polarized Raman and 81Br nuclear quadrupole resonance spectroscopies. Preliminary attempts to suppress unintentional hole doping to allow for ferroelectric switching are described. Together, the polar symmetry, small band gap, large spin-orbit splitting of Sn 5p orbitals, and predicted strain sensitivity of the symmetry-breaking distortions suggest bulk samples and epitaxial films of CsSnBr3 or its neighboring solid solutions as candidates for bulk Rashba effects.

8.
Breast Cancer Res ; 26(1): 102, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886818

RESUMO

BACKGROUND: Early menarche is an established risk factor for breast cancer but its molecular contribution to tumor biology and prognosis remains unclear. METHODS: We profiled transcriptome-wide gene expression in breast tumors (N = 846) and tumor-adjacent normal tissues (N = 666) from women in the Nurses' Health Studies (NHS) to investigate whether early menarche (age < 12) is associated with tumor molecular and prognostic features in women with breast cancer. Multivariable linear regression and pathway analyses using competitive gene set enrichment analysis were conducted in both tumor and adjacent-normal tissue and externally validated in TCGA (N = 116). Subgroup analyses stratified on ER-status based on the tumor were also performed. PAM50 signatures were used for tumor molecular subtyping and to generate proliferation and risk of recurrence scores. We created a gene expression score using LASSO regression to capture early menarche based on 28 genes from FDR-significant pathways in breast tumor tissue in NHS and tested its association with 10-year disease-free survival in both NHS (N = 836) and METABRIC (N = 952). RESULTS: Early menarche was significantly associated with 369 individual genes in adjacent-normal tissues implicated in extracellular matrix, cell adhesion, and invasion (FDR ≤ 0.1). Early menarche was associated with upregulation of cancer hallmark pathways (18 significant pathways in tumor, 23 in tumor-adjacent normal, FDR ≤ 0.1) related to proliferation (e.g. Myc, PI3K/AKT/mTOR, cell cycle), oxidative stress (e.g. oxidative phosphorylation, unfolded protein response), and inflammation (e.g. pro-inflammatory cytokines IFN α and IFN γ ). Replication in TCGA confirmed these trends. Early menarche was associated with significantly higher PAM50 proliferation scores (ß = 0.082 [0.02-0.14]), odds of aggressive molecular tumor subtypes (basal-like, OR = 1.84 [1.18-2.85] and HER2-enriched, OR = 2.32 [1.46-3.69]), and PAM50 risk of recurrence score (ß = 4.81 [1.71-7.92]). Our NHS-derived early menarche gene expression signature was significantly associated with worse 10-year disease-free survival in METABRIC (N = 952, HR = 1.58 [1.10-2.25]). CONCLUSIONS: Early menarche is associated with more aggressive molecular tumor characteristics and its gene expression signature within tumors is associated with worse 10-year disease-free survival among women with breast cancer. As the age of onset of menarche continues to decline, understanding its relationship to breast tumor characteristics and prognosis may lead to novel secondary prevention strategies.


Assuntos
Neoplasias da Mama , Perfilação da Expressão Gênica , Menarca , Recidiva Local de Neoplasia , Transcriptoma , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Menarca/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Pessoa de Meia-Idade , Prognóstico , Adulto , Biomarcadores Tumorais/genética , Fatores de Risco , Regulação Neoplásica da Expressão Gênica , Fatores Etários
9.
Int J Eat Disord ; 57(2): 265-285, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38111296

RESUMO

OBJECTIVE: This systematic review updates an existing review examining the cost-effectiveness of interventions to prevent and treat eating disorders (EDs). METHOD: Literature search was conducted in Academic Search Complete, MEDLINE, CINAHL, PsycINFO, EconLit, Global Health, ERIC, Health Business Elite, and Health Policy Reference Center electronic databases, capturing studies published between March 2017 to April 2023. Hand-searching was conducted as supplementary including gray literature search. Included articles were (1) full economic evaluations or return-on-investment studies, (2) in English and (3) aimed at prevention and treatment of any ED. Included studies were added and synthesized with previously reviewed studies. Screening and extraction followed PRISMA guidelines. Quality assessment was conducted using the Drummond checklist. PROSPERO registration CRD42021287464. RESULTS: A total of 28 studies were identified, including 15 published after the previous review. There were nine prevention, seven anorexia nervosa (AN) treatment, five bulimia nervosa (BN) treatment, four binge-eating disorder (BED), and three non-specific ED treatment studies. Findings indicate value-for-money evidence supporting all interventions. Quality assessment showed studies were fair-to-good quality. DISCUSSION: There has been significant growth in cost-effectiveness studies over the last 5 years. Findings suggest that interventions to prevent and treat ED offer value for money. Interventions such as Featback (ED prevention and non-specific ED treatment); focal psychodynamic therapy, enhanced cognitive behavioral therapy, and high-calorie refeeding (AN treatment); stepped-care with assisted self-help and internet-based cognitive behavioral therapy (BN treatment); and cognitive behavioral therapy guided self-help intervention (BED treatment) have good quality economic evidence. Further research in implementation of interventions is required. PUBLIC SIGNIFICANCE STATEMENT: The increasing prevalence of ED globally has significant impact on healthcare systems, families, and society. This review is showcasing the value for money of interventions of eating disorders prevention and treatment. This review found that existing interventions offers positive economic benefit for the healthcare system.


OBJETIVO: Esta revisión sistemática actualiza una revisión existente que examina la rentabilidad de las intervenciones para prevenir y tratar los trastornos de la conducta alimentaria (TCA). MÉTODO: Se realizó una búsqueda bibliográfica en las bases de datos electrónicas Academic Search Complete, MEDLINE, CINAHL, PsycINFO, EconLit, Global Health, ERIC, Health Business Elite y Health Policy Reference Center, abarcando estudios publicados entre marzo de 2017 y abril de 2023. Se realizó una búsqueda manual como complemento, incluyendo la búsqueda de literatura gris. Los artículos incluidos eran (1) evaluaciones económicas completas o estudios de retorno de inversión, (2) en inglés y (3) dirigidos a la prevención y tratamiento de cualquier TCA. Los estudios incluidos se añadieron y sintetizaron con estudios previamente revisados. El cribado y la extracción siguieron las pautas PRISMA. La evaluación de la calidad se realizó utilizando la lista de verificación de Drummond. Registro en PROSPERO CRD42021287464. RESULTADOS: Se identificaron 28 estudios, incluyendo 15 publicados después de la revisión anterior. Hubo nueve estudios de prevención, siete de tratamiento de anorexia nerviosa (AN), cinco de tratamiento de bulimia nerviosa (BN), cuatro de trastorno por atracón (TpA) y tres de tratamiento de TCA no especificados. Los hallazgos indican evidencia de valor por dinero que respalda todas las intervenciones. La evaluación de la calidad mostró que los estudios eran de calidad aceptable a buena. DISCUSIÓN: Ha habido un crecimiento significativo en los estudios de rentabilidad en los últimos cinco años. Los hallazgos sugieren que las intervenciones para prevenir y tratar los TCA ofrecen valor por dinero. Intervenciones como Featback (prevención de TCA y tratamiento de TCA no específicos); terapia psicodinámica focal, terapia cognitivo-conductual mejorada y rehabilitación nutricional con alto contenido calórico (tratamiento de AN); atención escalonada con autoayuda asistida y terapia cognitivo-conductual en línea (tratamiento de BN); y terapia cognitivo-conductual guiada de autoayuda (tratamiento de TpA) tienen una buena evidencia económica de calidad. Se requiere más investigación en la implementación de intervenciones.


Assuntos
Anorexia Nervosa , Transtorno da Compulsão Alimentar , Bulimia Nervosa , Terapia Cognitivo-Comportamental , Transtornos da Alimentação e da Ingestão de Alimentos , Humanos , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Bulimia Nervosa/psicologia , Transtorno da Compulsão Alimentar/psicologia , Anorexia Nervosa/terapia , Análise Custo-Benefício
10.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38676043

RESUMO

The Polar Qualification System (PQS) was applied on hue spectra fingerprinting to describe color changes in tomato during storage. The cultivar 'Pitenza' was harvested at six different maturity stages, and half of the samples were subjected to gaseous 1-methylcyclopropene (1-MCP) treatment. Reference color parameters were recorded with a vision system colorimeter instrument, and the fruit pigment concentration was assessed with the DA-index®. Additionally, acoustic firmness (Stiffness) was measured. All acquired reference parameters were used to grade fruit in the supply chain. The applied 1-MCP treatments were used to control the ripening of climacteric horticultural produce. Both the DA-index® and stiffness values, presented as chlorophyll concentration and acoustic firmness, showed significant differences among maturity stages and treated and control samples and in their kinetics during storage. The machine vision parameter PQS-X was significantly affected by 1-MCP treatment (F = 10.18, p < 0.01), while PQS-Y was primarily affected by storage time (F = 18.18, p < 0.01) and maturity stage (F = 11.15, p < 0.01). A significant correlation was achieved for acoustic firmness with normalized color (r > 0.78) and PQS-Y (r > 0.80), as well as for the DA-index® (r > 0.9). The observed color changes agreed with the reference measurements. The significant statistical effect on the PQS coordinates suggests that hue spectra fingerprinting with this data compression technique is suitable for quality assessment based on color.


Assuntos
Cor , Ciclopropanos , Solanum lycopersicum , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Ciclopropanos/farmacologia , Frutas/química , Frutas/efeitos dos fármacos , Pigmentação/efeitos dos fármacos , Pigmentação/fisiologia , Clorofila/análise , Clorofila/metabolismo , Pigmentos Biológicos/análise
11.
Stem Cells ; 40(4): 397-410, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35385105

RESUMO

Somatic cell reprogramming proceeds through a series of events to generate induced pluripotent stem cells (iPSCs). The early stage of reprogramming of mouse embryonic fibroblasts is characterized by rapid cell proliferation and morphological changes, which are accompanied by downregulation of mesenchyme-associated genes. However, the functional relevance of their downregulation to reprogramming remains poorly defined. In this study, we have screened transcriptional regulators that are downregulated immediately upon reprogramming, presumably through direct targeting by reprogramming factors. To test if these transcriptional regulators impact reprogramming when expressed continuously, we generated an expression vector that harbors human cytomegalovirus upstream open reading frame 2 (uORF2), which reduces translation to minimize the detrimental effect of an expressed protein. Screening of transcriptional regulators with this expression vector revealed that downregulation of (odd-skipped related 2 [Osr2]) is crucial for efficient reprogramming. Using a cell-based model for epithelial-mesenchymal transition (EMT), we show that Osr2 is a novel EMT regulator that acts through induction of transforming growth factor-ß (TGF-ß) signaling. During reprogramming, Osr2 downregulation not only diminishes TGF-ß signaling but also allows activation of Wnt signaling, thus promoting mesenchymal-epithelial transition (MET) toward acquisition of pluripotency. Our results illuminate the functional significance of Osr2 downregulation in erasing the mesenchymal phenotype at an early stage of somatic cell reprogramming.


Assuntos
Transição Epitelial-Mesenquimal , Células-Tronco Pluripotentes Induzidas , Animais , Reprogramação Celular/genética , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
12.
Mol Cell Proteomics ; 20: 100133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34391888

RESUMO

MS is the most effective method to directly identify peptides presented on human leukocyte antigen (HLA) molecules. However, current standard approaches often use 500 million or more cells as input to achieve high coverage of the immunopeptidome, and therefore, these methods are not compatible with the often limited amounts of tissue available from clinical tumor samples. Here, we evaluated microscaled basic reversed-phase fractionation to separate HLA peptide samples offline followed by ion mobility coupled to LC-MS/MS for analysis. The combination of these two separation methods enabled identification of 20% to 50% more peptides compared with samples analyzed without either prior fractionation or use of ion mobility alone. We demonstrate coverage of HLA immunopeptidomes with up to 8107 distinct peptides starting with as few as 100 million cells. The increased sensitivity obtained using our methods can provide data useful to improve HLA-binding prediction algorithms as well as to enable detection of clinically relevant epitopes such as neoantigens.


Assuntos
Antígenos de Neoplasias/análise , Antígenos de Histocompatibilidade Classe I/análise , Peptídeos/análise , Linhagem Celular , Fracionamento Químico , Cromatografia Líquida , Humanos , Espectrometria de Mobilidade Iônica , Neoplasias/química , Espectrometria de Massas em Tandem
13.
BMC Med Ethics ; 24(1): 3, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647039

RESUMO

BACKGROUND: The informed consent process in clinical trials has been extensively studied to inform the development processes which protect research participants and encourage their autonomy. However, ensuring a meaningful informed consent process is still of great concern in many research settings due to its complexity in practice and interwined socio-cultural factors. OBJECTIVES: This study explored the practices and meaning of the informed consent process in two clinial trials conducted by Oxford University Clinical Research Unit in collaboration with the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam. METHODS: We used multiple data collection methods including direct observervations, in-depth interviews with study physicians and trial participants, review of informed consent documents from 2009 to 2018, and participant observation with patients' family members. We recruited seven physicians and twenty-five trial participants into the study, of whom five physicians and thirteen trial participants completed in-depth interviews, and we held twenty-two direct observation sessions. RESULTS: We use the concept "fragmented understanding" to describe the nuances of understanding about the consent process and unpack underlying reasons for differing understandings. CONCLUSIONS: Our findings show how practices of informed consent and different understanding of the trial information are shaped by trial participants' characteristics and the socio-cultural context in which the trials take place.


Assuntos
Consentimento Livre e Esclarecido , Médicos , Humanos , Vietnã , Família
14.
J Craniofac Surg ; 34(2): 611-615, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36044275

RESUMO

INTRODUCTION: The use of surgical resection for large anterior skull base (ASB) tumors and sinonasal malignancies with intracranial extension will result in a large skull base defect. Reconstruction of large ASB defects using traditional techniques is high risk and may lead to postoperative cerebral spinal fluid (CSF) leakage, meningitis, and an increase in mortality rate. The use of a pedicled double flap technique to reconstruct the ASB defect may decrease complications. This study presents the clinical outcomes of patients who underwent double flap reconstruction techniques after resection of their sinonasal malignancies with significant intracranial extension at Cho Ray hospital in Vietnam. METHODS: The case series study was conducted at Cho Ray hospital from September 2010 to September 2020. All patients with large sinonasal malignancies that invaded intracranially underwent transnasal endoscopic surgery and subfrontal craniotomy. Reconstruction of large skull base defects (>2 cm) were followed up by using the pedicled double flaps technique. This study was performed in line with the principles of the Declaration of Helsinki. Approval of the study was granted by the Independent Ethics Committee of Cho Ray Hospital (Date: March 3, 2014/No: 11/BVCRHDDD). RESULTS: During September 2010 to September 2020, there were 75 patients who underwent a modified multilayer, double flap reconstruction technique after the resection of their ASB tumor. Skull base defects were commonly seen along the horizontal plate of the ethmoid bone and the ethmoid roof (98.6%). Large skull base defects (>2 cm) accounted for 81.3% of cases. Overall, the risk of postoperative CSF leakage and meningitis after double flap repair was considerably low. Of all participants, only 1 experienced postoperative CSF leakage and 1 experienced postoperative meningitis. Despite the complications, these patients improved significantly and remained stable. CONCLUSION: The use of double vascularized pedicled flaps may decrease the incidence of postoperative CSF leakage and meningitis. This technique is an effective method for the reconstruction of ASB tumors with large defects.


Assuntos
Doenças Ósseas , Procedimentos de Cirurgia Plástica , Neoplasias da Base do Crânio , Humanos , Retalhos Cirúrgicos/cirurgia , Base do Crânio/cirurgia , Osso Etmoide/cirurgia , Neoplasias da Base do Crânio/cirurgia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Doenças Ósseas/cirurgia
15.
Sensors (Basel) ; 23(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36991703

RESUMO

An electrocardiogram (ECG) is a basic and quick test for evaluating cardiac disorders and is crucial for remote patient monitoring equipment. An accurate ECG signal classification is critical for real-time measurement, analysis, archiving, and transmission of clinical data. Numerous studies have focused on accurate heartbeat classification, and deep neural networks have been suggested for better accuracy and simplicity. We investigated a new model for ECG heartbeat classification and found that it surpasses state-of-the-art models, achieving remarkable accuracy scores of 98.5% on the Physionet MIT-BIH dataset and 98.28% on the PTB database. Furthermore, our model achieves an impressive F1-score of approximately 86.71%, outperforming other models, such as MINA, CRNN, and EXpertRF on the PhysioNet Challenge 2017 dataset.


Assuntos
Arritmias Cardíacas , Infarto do Miocárdio , Eletrocardiografia , Frequência Cardíaca , Arritmias Cardíacas/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Humanos , Aprendizado de Máquina
16.
Sensors (Basel) ; 23(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36617077

RESUMO

Determining and applying 'good' postharvest and quality control practices for otherwise highly sensitive fruits, such as sour cherry, is critical, as they serve as excellent media for a wide variety of microbial contaminants. The objective of this research was to report two series of experiments on the modified atmosphere storage (MAP) of sour cherries (Prunus cerasus L. var. Kántorjánosi, Újfehértói fürtös). Firstly, the significant effect of different washing pre-treatments on various quality indices was examined (i.e., headspace gas composition, weight loss, decay rate, color, firmness, soluble solid content, total plate count) in MAP-packed fruits. Subsequently, the applicability of near infrared (NIR) spectroscopy combined with chemometrics was investigated to detect the effect of various storage conditions (packed as control or MAP, stored at 3 or 5 °C) on sour cherries of different perceived ripeness. Significant differences were found for oxygen concentration when two perforations were applied on the packages of 'Kántorjánosi' (p < 0.01); weight loss when 'Kánorjánosi' (p < 0.001) and 'Újfehértói fürtös' (p < 0.01) were packed in MAP; SSC when 'Újfehértói fürtös' samples were ozone-treated (p < 0.05); and total plate count when 'Kántorjánosi' samples were ozone-treated (p < 0.01). The difference spectra reflected the high variability in the samples, and the detectable effects of different packaging. Based on the investigations with the soft independent modelling of class analogies (SIMCA), different packaging and storage resulted in significant differences in most of the cases even on the first storage day, which in many cases increased by the end of storage. The soft independent modelling of class analogies proved to be suitable for classification with apparent error rates between 0 and 0.5 during prediction regardless of ripeness. The research findings suggest the further correlation of NIR spectroscopic and reference parameters to support postharvest handling and fast quality control.


Assuntos
Ozônio , Prunus avium , Prunus avium/química , Espectroscopia de Luz Próxima ao Infravermelho , Frutas/química , Ozônio/análise , Atmosfera
17.
Molecules ; 28(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37570892

RESUMO

Coffee pulp is an abundant residue from the coffee industry, but it still contains large amounts of valuable compounds such as polyphenols. The extraction of polyphenols from coffee pulp by the conventional method is accompanied by contaminated compounds. This study, therefore, applied an aqueous two-phase system consisting of different ratios of ethanol/ammonium sulfate to eliminate impurities from coffee-pulp crude extract. The purification efficiency was evaluated via total polyphenol content, antioxidant activity and two major polyphenols in coffee pulps including chlorogenic acid and caffeic acid. Results showed that phenolic compounds mostly predominated in the alcohol-rich phase in which the antioxidant activity was greatly increased after the purification process. Compared to un-purified crude-coffee extract, the antioxidant activity of the purified samples increased approximately 34%, which was assumed to occur due to the slight increase of chlorogenic acid and caffeic acid. Fourier-transform infrared spectroscopy supported the effectiveness of the purification process by eliminating some impurities.


Assuntos
Ácido Clorogênico , Polifenóis , Antioxidantes/farmacologia , Ácidos Cafeicos , Extratos Vegetais/química , Etanol
18.
Indian J Microbiol ; 63(4): 596-603, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38031615

RESUMO

Endophytic fungi are known as an alternative promising source of anticancer drug, paclitaxel, however fungi inhabiting in medicinal plant Podocarpus pilgeri and their paclitaxel production have not been reported to date. In the present study, a total of 15 culturable fungi classified into 5 genera, were successfully recovered from P. pilgeri collected in Vietnam. Screening fungal dichloromethane extracts for anticancer activity revealed that only PQF9 extract displayed potent inhibitory effects on A549 and MCF7 cancer cell lines with IC50 values of 33.9 ± 2.3 µg/mL and 43.5 ± 1.7 µg/mL, respectively. Through PCR-based molecular screening, the isolate PQF9 was found to possess 3 key genes involved in paclitaxel biosynthesis. Importantly, high-performance liquid chromatography quantification showed that fungal isolate PQF9 was able to produce 18.2 µg/L paclitaxel. The paclitaxel-producing fungus was identified as Fusarium solani PQF9 based on morphological and molecular phylogenetic analysis. Intensive investigations by chromatographic methods and spectroscopic analyses confirmed the presence of paclitaxel along with tyrosol and uracil. The pure paclitaxel had an IC50 value of 80.8 ± 9.4 and 67.9 ± 7.0 nM by using cell viability assay on A549 lung and MCF7 breast cancer cells. In addition, tyrosol exhibited strong antioxidant activity by scavenging 2, 2-diphenyl-picrylhydrazyl (DPPH) (IC50 5.1 ± 0.2 mM) and hydroxyl radical (IC50 3.6 ± 0.1 mM). In contrast, no biological activity was observed for uracil. Thus, the paclitaxel-producing fungus F. solani PQF9 could serve as a new material for large-scale production and deciphering paclitaxel biosynthesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01119-z.

19.
Gut ; 71(12): 2463-2480, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35017197

RESUMO

OBJECTIVES: Gut microbiota is a key component in obesity and type 2 diabetes, yet mechanisms and metabolites central to this interaction remain unclear. We examined the human gut microbiome's functional composition in healthy metabolic state and the most severe states of obesity and type 2 diabetes within the MetaCardis cohort. We focused on the role of B vitamins and B7/B8 biotin for regulation of host metabolic state, as these vitamins influence both microbial function and host metabolism and inflammation. DESIGN: We performed metagenomic analyses in 1545 subjects from the MetaCardis cohorts and different murine experiments, including germ-free and antibiotic treated animals, faecal microbiota transfer, bariatric surgery and supplementation with biotin and prebiotics in mice. RESULTS: Severe obesity is associated with an absolute deficiency in bacterial biotin producers and transporters, whose abundances correlate with host metabolic and inflammatory phenotypes. We found suboptimal circulating biotin levels in severe obesity and altered expression of biotin-associated genes in human adipose tissue. In mice, the absence or depletion of gut microbiota by antibiotics confirmed the microbial contribution to host biotin levels. Bariatric surgery, which improves metabolism and inflammation, associates with increased bacterial biotin producers and improved host systemic biotin in humans and mice. Finally, supplementing high-fat diet-fed mice with fructo-oligosaccharides and biotin improves not only the microbiome diversity, but also the potential of bacterial production of biotin and B vitamins, while limiting weight gain and glycaemic deterioration. CONCLUSION: Strategies combining biotin and prebiotic supplementation could help prevent the deterioration of metabolic states in severe obesity. TRIAL REGISTRATION NUMBER: NCT02059538.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Obesidade Mórbida , Complexo Vitamínico B , Humanos , Camundongos , Animais , Prebióticos , Obesidade Mórbida/cirurgia , Biotina/farmacologia , Complexo Vitamínico B/farmacologia , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Inflamação
20.
Nat Chem Biol ; 16(2): 188-196, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31959964

RESUMO

Allosteric modulators of ion channels typically alter the transitions rates between conformational states without changing the properties of the open pore. Here we describe a new class of positive allosteric modulators of N-methyl D-aspartate receptors (NMDARs) that mediate a calcium-permeable component of glutamatergic synaptic transmission and play essential roles in learning, memory and cognition, as well as neurological disease. EU1622-14 increases agonist potency and channel-open probability, slows receptor deactivation and decreases both single-channel conductance and calcium permeability. The unique functional selectivity of this chemical probe reveals a mechanism for enhancing NMDAR function while limiting excess calcium influx, and shows that allosteric modulators can act as biased modulators of ion-channel permeation.


Assuntos
Pirrolidinas/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Cálcio/metabolismo , Células Cultivadas , Feminino , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Glicina/metabolismo , Glicina/farmacologia , Células HEK293 , Ensaios de Triagem em Larga Escala/métodos , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/genética , Xenopus laevis
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