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1.
Ann Nucl Med ; 37(11): 605-617, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37598412

RESUMO

OBJECTIVES: This study aimed to establish a radiomics model based on 18F-FDG PET/CT images to predict visceral pleural invasion (VPI) of solid lung adenocarcinoma preoperatively. METHODS: We retrospectively enrolled 165 solid lung adenocarcinoma patients confirmed by histopathology with 18F-FDG PET/CT images. Patients were divided into training and validation at a ratio of 0.7. To find significant VPI predictors, we collected clinicopathological information and metabolic parameters measured from PET/CT images. Three-dimensional (3D) radiomics features were extracted from each PET and CT volume of interest (VOI). Receiver operating characteristic (ROC) curve was performed to determine the performance of the model. Accuracy, sensitivity, specificity and area under curve (AUC) were calculated. Finally, their performance was evaluated by concordance index (C-index) and decision curve analysis (DCA) in training and validation cohorts. RESULTS: 165 patients were divided into training cohort (n = 116) and validation cohort (n = 49). Multivariate analysis showed that histology grade, maximum standardized uptake value (SUVmax), distance from the lesion to the pleura (DLP) and the radiomics features had statistically significant differences between patients with and without VPI (P < 0.05). A nomogram was developed based on the logistic regression method. The accuracy of ROC curve analysis of this model was 75.86% in the training cohort (AUC: 0.867; C-index: 0.867; sensitivity: 0.694; specificity: 0.889) and the accuracy rate in validation cohort was 71.55% (AUC: 0.889; C-index: 0.819; sensitivity: 0.654; specificity: 0.739). CONCLUSIONS: A PET/CT-based radiomics model was developed with SUVmax, histology grade, DLP, and radiomics features. It can be easily used for individualized VPI prediction.

2.
Nucleic Acids Res ; 51(D1): D368-D376, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36478084

RESUMO

The Biological Magnetic Resonance Data Bank (BMRB, https://bmrb.io) is the international open data repository for biomolecular nuclear magnetic resonance (NMR) data. Comprised of both empirical and derived data, BMRB has applications in the study of biomacromolecular structure and dynamics, biomolecular interactions, drug discovery, intrinsically disordered proteins, natural products, biomarkers, and metabolomics. Advances including GHz-class NMR instruments, national and trans-national NMR cyberinfrastructure, hybrid structural biology methods and machine learning are driving increases in the amount, type, and applications of NMR data in the biosciences. BMRB is a Core Archive and member of the World-wide Protein Data Bank (wwPDB).


Assuntos
Bases de Dados de Compostos Químicos , Espectroscopia de Ressonância Magnética , Bases de Dados de Proteínas , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica
3.
Eur Radiol ; 33(5): 3354-3365, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36547676

RESUMO

OBJECTIVE: In this study, based on PET/CT radiomics features, we developed and validated a nomogram to predict progression-free survival (PFS) for cases with diffuse large B cell lymphoma (DLBCL) treated with immunochemotherapy. METHODS: This study retrospectively recruited 129 cases with DLBCL. Among them, PET/CT scans were conducted and baseline images were collected for radiomics features along with their clinicopathological features. Radiomics features related to recurrence were screened for survival analysis using univariate Cox regression analysis with p < 0.05. Next, a weighted Radiomics-score (Rad-score) was generated and independent risk factors were obtained from univariate and multivariate Cox regressions to build the nomogram. Furthermore, the nomogram was tested for their ability to predict PFS using time-dependent receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: Blood platelet, Rad-score, and gender were included in the nomogram as independent DLBCL risk factors for PFS. We found that the training cohort areas under the curve (AUCs) were 0.79, 0.84, and 0.88, and validation cohort AUCs were 0.67, 0.83, and 0.72, respectively. Further, the DCA and calibration curves confirmed the predictive nomogram's clinical relevance. CONCLUSION: Using Rad-score, blood platelet, and gender of the DLBCL patients, a PET/CT radiomics-based nomogram was developed to guide cases' recurrence risk assessment prior to treatment. The developed nomogram can help provide more appropriate treatment plans to the cases. KEY POINTS: • DLBCL cases can be classified into low- and high-risk groups using PET/CT radiomics based Rad-score. • When combined with other clinical characteristics (gender and blood platelet count), Rad-score can be used to predict the outcome of the pretreatment of DLBCL cases with a certain degree of accuracy. • A prognostic nomogram was established in this study in order to aid in assessing prognostic risk and providing more accurate treatment plans for DLBCL cases.


Assuntos
Linfoma Difuso de Grandes Células B , Nomogramas , Humanos , Prognóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18/farmacologia , Estudos Retrospectivos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem
4.
BMC Pediatr ; 22(1): 113, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236316

RESUMO

BACKGROUND: Retinopathy of prematurity (ROP) remains a leading cause of childhood blindness worldwide. This study aimed to investigate whether supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) in parenteral nutrition may have beneficial effects on ROP in preterm infants. METHODS: A total of 89 preterm infants, admitted to Neonatal Intensive Care Unit (NICU) in Anhui Provincial Children's Hospital from September 2017 to August 2020, were recruited in the study. Based on the medical documents, the subjects were categorised into two groups: administration of the fish oil emulsion (n=43) containing soy oil, medium-chain-triglycerides (MCT), olive oil and fish oil (6g/dL, 6g/dL, 5g/dL and 3g/dL respectively), and the soy oil emulsion (n=46) containing 10g/dL of soy oil and MCT each. At 4 weeks of hospitalization, ROP was screened and diagnosed. Fatty acids in erythrocytes were determined using gas chromatography. RESULTS: The averaged birth weight and gestational age were 1594±296 g and 31.9±2.3 wk, 1596±263 g and 31.6±2.3 wk respectively for preterm infants in the fish oil group and soy oil group. After 4 to 6 weeks of hospitalization, among all the preterm infants, 52 developed ROP (all stages) indicating an incidence of ROP at 58.43%. Although the incidence of ROP with any stages showed no differences between the two groups, the severe ROP incidence in the group with fish oil emulsions (2.33%) was significantly lower than that in the group with soy oil emulsions (23.91%) (P<0.05). After 14 days of nutrition support, the preterm infants administered fish oil emulsions had an increase in erythrocyte DHA content, with a reduction in ratio of arachidonic acid (AA) to DHA and an increase of n-3 index. CONCLUSION: Supplementation of n-3 PUFAs through parenteral fish oil containing lipid emulsions resulted in an increase in erythrocyte DHA, and this might have beneficial effects on prevention of severe ROP in preterm infants.


Assuntos
Ácidos Graxos Ômega-3 , Retinopatia da Prematuridade , Emulsões , Óleos de Peixe , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Óleo de Soja , Triglicerídeos
5.
Front Nutr ; 7: 589771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330591

RESUMO

Quantitative PCR (qPCR), the most accurate and sensitive technique for quantifying mRNA expression, and choice of appropriate reference genes for internal error controlling in qPCR are essential to understanding the molecular mechanisms that drive the obesity epidemic and its comorbidities. In this study, using the high-fat diet (HFD)-induced obese mouse model, we assessed the expression of 10 commonly used reference genes to validate gene-expression stability in adipose tissue, liver, and muscle across different time points (4, 8, 12, and 16 weeks after HFD feeding) during the process of obesity. The data were analyzed by the GeNorm, NormFinder, BestKeeper, and Delta-Ct method, and the results showed that the most stable reference genes were different for a specific organ or tissue in a specific time point; however, PPIA, RPLP0, and YWHAZ were the top three most stable reference genes in qPCR experiments on adipose, hepatic tissues, and muscles of mice in diet-induced obesity. In addition, the mostly used genes ACTB and GAPDH were more unstable in the fat and liver, the ACTB mRNA levels were increased in four adipose tissues, and the GAPDH mRNA levels were decreased in four adipose tissues and liver after HFD feeding. These results suggest that PPIA, RPLP0, or YWHAZ may be more appropriate to be used as reference gene than ACTB and GAPDH in the adipose tissue and liver of mice during the process of high-fat diet-induced obesity.

6.
Theranostics ; 10(15): 6854-6874, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32550908

RESUMO

Repeated failures of "Aß-lowering" therapies call for new targets and therapeutic approaches for Alzheimer's disease (AD). We propose to treat AD by halting neuronal death and repairing synapses using a BDNF-based therapy. To overcome the poor druggability of BDNF, we have developed an agonistic antibody AS86 to mimic the function of BDNF, and evaluate its therapeutic potential for AD. Method: Biochemical, electrophysiological and behavioral techniques were used to investigate the effects of AS86 in vitro and in vivo. Results: AS86 specifically activated the BDNF receptor TrkB and its downstream signaling, without affecting its other receptor p75NTR. It promoted neurite outgrowth, enhanced spine growth and prevented Aß-induced cell death in cultured neurons, and facilitated Long-Term Potentiation (LTP) in hippocampal slices. A single-dose tail-vein injection of AS86 activated TrkB signaling in the brain, with a half-life of 6 days in the blood and brain. Bi-weekly peripheral administration of AS86 rescued the deficits in object-recognition memory in the APP/PS1 mouse model. AS86 also reversed spatial memory deficits in the 11-month, but not 14-month old AD mouse model. Conclusion: These results demonstrate the potential of AS86 in AD therapy, suggesting that neuronal and/or synaptic repair as an alternative therapeutic strategy for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Anticorpos Monoclonais/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração , Plasticidade Neuronal , Receptor trkB/agonistas , Doença de Alzheimer/imunologia , Doença de Alzheimer/metabolismo , Animais , Células Cultivadas , Cricetinae , Modelos Animais de Doenças , Hipocampo/metabolismo , Fatores Imunológicos/farmacologia , Camundongos , Camundongos Transgênicos , Receptor trkB/metabolismo
7.
Genes Nutr ; 15(1): 12, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32586265

RESUMO

BACKGROUND: Adiponectin and resistin are typically secreted by the adipose tissue and are abnormally expressed in obesity. However, the underlying influential factors and mechanisms are to be elucidated. It is well known that the expression of genes is regulated by epigenetics while gut microbiota participates in epigenetic processes through its metabolites such as folate, biotin, and short-chain fatty acids (SCFAs). Therefore, we supposed that alteration of gut microbiota might affect the transcriptional expression of adiponectin and resistin through epigenetic regulation in obesity. METHODS: C57BL/6J mice were fed either a high-fat diet (34.9% fat by wt., 60% kcal) or a normal-fat diet (4.3% fat by wt., 10% kcal) for 16 weeks, with ampicillin and neomycin delivered via drinking water to interfere with gut microbiota development. Fecal microbiota was analyzed by 16S rRNA high-throughput sequencing. The mRNA expression levels of genes were measured by real-time quantitative RT-PCR. SCFA contents in feces were examined using gas chromatography. RESULTS: Alteration of the gut microbiota induced by antibiotic use, characterized by a dramatic reduction of the phylum Firmicutes and Actinobacteria and an increase of Proteobacteria with reductions of genera including Lactobacillus, norank_f_Bacteroidales_S24-7_group, Alistipes, Desulfovibrio, Helicobacter, etc., and increases in Bacteroides, Enterobacter, Klebsiella, inhibited the body weight gain in mice fed the high-fat diet instead of the normal-fat diet. The mRNA expression of adiponectin and resistin was upregulated by antibiotic use in mice fed the high-fat diet, accompanied by increased expression of fat oxidation and thermogenesis-related genes (PPAR-α, Pgc-1α, and Atgl) in the fat and/or liver, whereas no change in the expression of adiponectin and resistin was found in mice fed the normal-fat diet. Furthermore, antibiotic use reduced DNA methylation fractions of the adiponectin and resistin promoters and downregulated the expression of DNA methyltransferase 1 and 3a (DNMT1 and DNMT3a) with the high-fat diet feeding. CONCLUSION: Alteration of gut microbiota induced by antibiotic use may affect the expression of adiponectin and resistin in mice fed the high-fat diet by modifying promoter DNA methylation, thus leading to increased fatty acid oxidation and less body weight gain.

8.
Br J Nutr ; 124(4): 396-406, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32213218

RESUMO

Aberration in leptin expression is one of the most frequent features in the onset and progression of obesity, but the underlying mechanisms are still unclear and need to be clarified. This study investigated the effects of the absence of gut microbiota on body weight and the expression and promoter methylation of the leptin. Male C57 BL/6 J germ-free (GF) and conventional (CV) mice (aged 4-5 weeks) were fed either a normal-fat diet (NFD) or a high-fat diet (HFD) for 16 weeks. Six to eight mice from each group, at 15 weeks, were administered exogenous leptin for 7 d. Leptin expression and body weight gain in GF mice were increased by NFD with more CpG sites hypermethylated at the leptin promoter, whereas there was no change with HFD, compared with CV mice. Adipose or hepatic expression of genes associated with fat synthesis (Acc1, Fas and Srebp-1c), hydrolysis and oxidation (Atgl, Cpt1a, Cpt1c, Ppar-α and Pgc-1α) was lower, and hypothalamus expression of Pomc and Socs3 was higher in GF mice than levels in CV mice, particularly with NFD feeding. Exogenous leptin reduced body weight in both types of mice, with a greater effect on CV mice with NFD. Adipose Lep-R expression was up-regulated, and hepatic Fas and hypothalamic Socs3 were down-regulated in both types of mice. Expression of fat hydrolysis and oxidative genes (Atgl, Hsl, Cpt1a, Cpt1c, Ppar-α and Pgc-1α) was up-regulated in CV mice. Therefore, the effects of gut microbiota on the leptin expression and body weight were affected by dietary fat intake.


Assuntos
Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Leptina/metabolismo , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Adiposidade/genética , Animais , Modelos Animais de Doenças , Hipotálamo/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Pró-Opiomelanocortina/metabolismo , Receptores para Leptina/metabolismo
9.
Methods Mol Biol ; 2112: 187-218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32006287

RESUMO

The Biological Magnetic Resonance Data Bank (BioMagResBank or BMRB), founded in 1988, serves as the archive for data generated by nuclear magnetic resonance (NMR) spectroscopy of biological systems. NMR spectroscopy is unique among biophysical approaches in its ability to provide a broad range of atomic and higher-level information relevant to the structural, dynamic, and chemical properties of biological macromolecules, as well as report on metabolite and natural product concentrations in complex mixtures and their chemical structures. BMRB became a core member of the Worldwide Protein Data Bank (wwPDB) in 2007, and the BMRB archive is now a core archive of the wwPDB. Currently, about 10% of the structures deposited into the PDB archive are based on NMR spectroscopy. BMRB stores experimental and derived data from biomolecular NMR studies. Newer BMRB biopolymer depositions are divided about evenly between those associated with structure determinations (atomic coordinates and supporting information archived in the PDB) and those reporting experimental information on molecular dynamics, conformational transitions, ligand binding, assigned chemical shifts, or other results from NMR spectroscopy. BMRB also provides resources for NMR studies of metabolites and other small molecules that are often macromolecular ligands and/or nonstandard residues. This chapter is directed to the structural biology community rather than the metabolomics and natural products community. Our goal is to describe various BMRB services offered to structural biology researchers and how they can be accessed and utilized. These services can be classified into four main groups: (1) data deposition, (2) data retrieval, (3) data analysis, and (4) services for NMR spectroscopists and software developers. The chapter also describes the NMR-STAR data format used by BMRB and the tools provided to facilitate its use. For programmers, BMRB offers an application programming interface (API) and libraries in the Python and R languages that enable users to develop their own BMRB-based tools for data analysis, visualization, and manipulation of NMR-STAR formatted files. BMRB also provides users with direct access tools through the NMRbox platform.


Assuntos
Substâncias Macromoleculares/química , Biologia Molecular/métodos , Conformação Proteica , Proteínas/química , Bases de Dados de Proteínas , Ligantes , Ressonância Magnética Nuclear Biomolecular/métodos , Software
10.
Neurobiol Dis ; 132: 104590, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31470106

RESUMO

While Brain-derived Neurotrophic Factor (BDNF) has long been implicated in treating neurological diseases, recombinant BDNF protein has failed in multiple clinical trials. In addition to its unstable and adhesive nature, BDNF can activate p75NTR, a receptor mediating cellular functions opposite to those of TrkB. We have now identified TrkB agonistic antibodies (TrkB-agoAbs) with several properties superior to BDNF: They exhibit blood half-life of days instead of hours, diffuse centimeters in neural tissues instead millimeters, and bind and activate TrkB, but not p75NTR. In addition, TrkB-agoAbs elicit much longer TrkB activation, reduced TrkB internalization and less intracellular degradation, compared with BDNF. More importantly, some of these TrkB-agoAbs bind TrkB epitopes distinct from that by BDNF, and work cooperatively with endogenous BDNF. Unlike BDNF, the TrkB-agoAbs exhibit a half-life of days/weeks and diffused readily in nerve tissues. We tested one of TrkB-agoAbs further and showed that it enhanced motoneuron survival in the spinal-root avulsion model for motoneuron degeneration in vivo. Thus, TrkB-agoAbs are promising drug candidates for the treatment of neural injury.


Assuntos
Anticorpos Monoclonais/farmacologia , Neurônios Motores/efeitos dos fármacos , Degeneração Neural/patologia , Fármacos Neuroprotetores/farmacologia , Receptor trkB/agonistas , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Humanos , Neurônios Motores/patologia
11.
J Biomol NMR ; 73(1-2): 5-9, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30580387

RESUMO

The growth of the biological nuclear magnetic resonance (NMR) field and the development of new experimental technology have mandated the revision and enlargement of the NMR-STAR ontology used to represent experiments, spectral and derived data, and supporting metadata. We present here a brief description of the NMR-STAR ontology and software tools for manipulating NMR-STAR data files, editing the files, extracting selected data, and creating data visualizations. Detailed information on these is accessible from the links provided.


Assuntos
Ontologias Biológicas , Ressonância Magnética Nuclear Biomolecular , Armazenamento e Recuperação da Informação , Software , Vocabulário Controlado
12.
Nucleic Acids Res ; 36(Database issue): D402-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17984079

RESUMO

The BioMagResBank (BMRB: www.bmrb.wisc.edu) is a repository for experimental and derived data gathered from nuclear magnetic resonance (NMR) spectroscopic studies of biological molecules. BMRB is a partner in the Worldwide Protein Data Bank (wwPDB). The BMRB archive consists of four main data depositories: (i) quantitative NMR spectral parameters for proteins, peptides, nucleic acids, carbohydrates and ligands or cofactors (assigned chemical shifts, coupling constants and peak lists) and derived data (relaxation parameters, residual dipolar couplings, hydrogen exchange rates, pK(a) values, etc.), (ii) databases for NMR restraints processed from original author depositions available from the Protein Data Bank, (iii) time-domain (raw) spectral data from NMR experiments used to assign spectral resonances and determine the structures of biological macromolecules and (iv) a database of one- and two-dimensional (1)H and (13)C one- and two-dimensional NMR spectra for over 250 metabolites. The BMRB website provides free access to all of these data. BMRB has tools for querying the archive and retrieving information and an ftp site (ftp.bmrb.wisc.edu) where data in the archive can be downloaded in bulk. Two BMRB mirror sites exist: one at the PDBj, Protein Research Institute, Osaka University, Osaka, Japan (bmrb.protein.osaka-u.ac.jp) and the other at CERM, University of Florence, Florence, Italy (bmrb.postgenomicnmr.net/). The site at Osaka also accepts and processes data depositions.


Assuntos
Bases de Dados Factuais , Ressonância Magnética Nuclear Biomolecular , Carboidratos/química , Internet , Ligantes , Ácidos Nucleicos/química , Peptídeos/química , Proteínas/química , Interface Usuário-Computador
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