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1.
Cell ; 161(6): 1437-52, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26046443

RESUMO

Germ cells are vital for transmitting genetic information from one generation to the next and for maintaining the continuation of species. Here, we analyze the transcriptome of human primordial germ cells (PGCs) from the migrating stage to the gonadal stage at single-cell and single-base resolutions. Human PGCs show unique transcription patterns involving the simultaneous expression of both pluripotency genes and germline-specific genes, with a subset of them displaying developmental-stage-specific features. Furthermore, we analyze the DNA methylome of human PGCs and find global demethylation of their genomes. Approximately 10 to 11 weeks after gestation, the PGCs are nearly devoid of any DNA methylation, with only 7.8% and 6.0% of the median methylation levels in male and female PGCs, respectively. Our work paves the way toward deciphering the complex epigenetic reprogramming of the germline with the aim of restoring totipotency in fertilized oocytes.


Assuntos
Metilação de DNA , Células Germinativas/metabolismo , Transcriptoma , Movimento Celular , Cromossomos Humanos X , Análise por Conglomerados , Embrião de Mamíferos/metabolismo , Feminino , Histonas/metabolismo , Humanos , Masculino , Análise de Componente Principal , Fatores de Transcrição SOX/metabolismo
2.
Nature ; 622(7983): 594-602, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37821698

RESUMO

Metagenomes encode an enormous diversity of proteins, reflecting a multiplicity of functions and activities1,2. Exploration of this vast sequence space has been limited to a comparative analysis against reference microbial genomes and protein families derived from those genomes. Here, to examine the scale of yet untapped functional diversity beyond what is currently possible through the lens of reference genomes, we develop a computational approach to generate reference-free protein families from the sequence space in metagenomes. We analyse 26,931 metagenomes and identify 1.17 billion protein sequences longer than 35 amino acids with no similarity to any sequences from 102,491 reference genomes or the Pfam database3. Using massively parallel graph-based clustering, we group these proteins into 106,198 novel sequence clusters with more than 100 members, doubling the number of protein families obtained from the reference genomes clustered using the same approach. We annotate these families on the basis of their taxonomic, habitat, geographical and gene neighbourhood distributions and, where sufficient sequence diversity is available, predict protein three-dimensional models, revealing novel structures. Overall, our results uncover an enormously diverse functional space, highlighting the importance of further exploring the microbial functional dark matter.


Assuntos
Metagenoma , Metagenômica , Microbiologia , Proteínas , Análise por Conglomerados , Metagenoma/genética , Metagenômica/métodos , Proteínas/química , Proteínas/classificação , Proteínas/genética , Bases de Dados de Proteínas , Conformação Proteica
3.
Mol Cell ; 79(6): 881-901, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32768408

RESUMO

Nucleosomes package genomic DNA into chromatin. By regulating DNA access for transcription, replication, DNA repair, and epigenetic modification, chromatin forms the nexus of most nuclear processes. In addition, dynamic organization of chromatin underlies both regulation of gene expression and evolution of chromosomes into individualized sister objects, which can segregate cleanly to different daughter cells at anaphase. This collaborative review shines a spotlight on technologies that will be crucial to interrogate key questions in chromatin and chromosome biology including state-of-the-art microscopy techniques, tools to physically manipulate chromatin, single-cell methods to measure chromatin accessibility, computational imaging with neural networks and analytical tools to interpret chromatin structure and dynamics. In addition, this review provides perspectives on how these tools can be applied to specific research fields such as genome stability and developmental biology and to test concepts such as phase separation of chromatin.


Assuntos
Cromatina/genética , Cromossomos/genética , DNA/genética , Nucleossomos/genética , Reparo do DNA/genética , Replicação do DNA/genética , Epigênese Genética/genética , Humanos
4.
Nucleic Acids Res ; 52(D1): D502-D512, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37811892

RESUMO

The Novel Metagenome Protein Families Database (NMPFamsDB) is a database of metagenome- and metatranscriptome-derived protein families, whose members have no hits to proteins of reference genomes or Pfam domains. Each protein family is accompanied by multiple sequence alignments, Hidden Markov Models, taxonomic information, ecosystem and geolocation metadata, sequence and structure predictions, as well as 3D structure models predicted with AlphaFold2. In its current version, NMPFamsDB hosts over 100 000 protein families, each with at least 100 members. The reported protein families significantly expand (more than double) the number of known protein sequence clusters from reference genomes and reveal new insights into their habitat distribution, origins, functions and taxonomy. We expect NMPFamsDB to be a valuable resource for microbial proteome-wide analyses and for further discovery and characterization of novel functions. NMPFamsDB is publicly available in http://www.nmpfamsdb.org/ or https://bib.fleming.gr/NMPFamsDB.


Assuntos
Bases de Dados de Proteínas , Metagenoma , Proteínas , Sequência de Aminoácidos , Bases de Dados Factuais , Ecossistema , Proteínas/química , Geografia
5.
J Transl Med ; 22(1): 26, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183100

RESUMO

BACKGROUND: (Pro)renin receptor (PRR) is highly expressed in renal tubules, which is involved in physiological and pathological processes. However, the role of PRR, expressed in renal tubular epithelial cells, in diabetic kidney disease (DKD) remain largely unknown. METHODS: In this study, kidney biopsies, urine samples, and public RNA-seq data from DKD patients were used to assess PRR expression and cell pyroptosis in tubular epithelial cells. The regulation of tubular epithelial cell pyroptosis by PRR was investigated by in situ renal injection of adeno-associated virus9 (AAV9)-shRNA into db/db mice, and knockdown or overexpression of PRR in HK-2 cells. To reveal the underlined mechanism, the interaction of PRR with potential binding proteins was explored by using BioGrid database. Furthermore, the direct binding of PRR to dipeptidyl peptidase 4 (DPP4), a pleiotropic serine peptidase which increases blood glucose by degrading incretins under diabetic conditions, was confirmed by co-immunoprecipitation assay and immunostaining. RESULTS: Higher expression of PRR was found in renal tubules and positively correlated with kidney injuries of DKD patients, in parallel with tubular epithelial cells pyroptosis. Knockdown of PRR in kidneys significantly blunted db/db mice to kidney injury by alleviating renal tubular epithelial cells pyroptosis and the resultant interstitial inflammation. Moreover, silencing of PRR blocked high glucose-induced HK-2 pyroptosis, whereas overexpression of PRR enhanced pyroptotic cell death of HK-2 cells. Mechanistically, PRR selectively bound to cysteine-enrich region of C-terminal of DPP4 and augmented the protein abundance of DPP4, leading to the downstream activation of JNK signaling and suppression of SIRT3 signaling and FGFR1 signaling, and then subsequently mediated pyroptotic cell death. CONCLUSIONS: This study identified the significant role of PRR in the pathogenesis of DKD; specifically, PRR promoted tubular epithelial cell pyroptosis via DPP4 mediated signaling, highlighting that PRR could be a promising therapeutic target in DKD.


Assuntos
Nefropatias Diabéticas , Receptor de Pró-Renina , Animais , Humanos , Camundongos , Diabetes Mellitus , Nefropatias Diabéticas/metabolismo , Dipeptidil Peptidase 4 , Células Epiteliais , Sistema de Sinalização das MAP Quinases , Receptor de Pró-Renina/metabolismo , Piroptose
6.
Exp Cell Res ; 424(2): 113512, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36775185

RESUMO

Excessive mitochondrial fission in podocytes is a critical feature of diabetic nephropathy (DN). Mitochondria-associated endoplasmic reticulum membranes (MAMs) are contact sites between the endoplasmic reticulum (ER) and mitochondria, which are suggested to be related to mitochondrial function. However, the role of MAMs in mitochondrial dynamics disorder in podocytes remains unknown. Here, we firstly reported a novel mechanism of MAMs' effects on mitochondrial dynamics in podocytes under diabetic conditions. Increased MAMs were found in diabetic podocytes in vivo and in vitro, which were positively correlated with excessive mitochondrial fission. What's more, we also found that A-kinase anchoring protein 1 (AKAP1) was located in MAMs, and its translocation to MAMs was increased in podocytes cultured with high glucose (HG). In addition, AKAP1 knockdown significantly reduced mitochondrial fission and attenuated high glucose induced-podocyte injury through regulating phosphorylation of dynamin-related protein 1 (Drp1) and its subsequent mitochondrial translocation. On the contrary, AKAP1 overexpression in these podocytes showed the opposite effect. Finally, pharmacological inhibition of Drp1 alleviated excessive mitochondrial fission and podocyte damage in AKAP1 overexpressed podocytes. Our data suggest that MAMs were increased in podocytes under diabetic conditions, leading to excessive mitochondrial fission and podocyte damage through AKAP1-Drp1 signaling.


Assuntos
Podócitos , Dinaminas/metabolismo , Retículo Endoplasmático/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Podócitos/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo
7.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33712545

RESUMO

The protein design problem is to identify an amino acid sequence that folds to a desired structure. Given Anfinsen's thermodynamic hypothesis of folding, this can be recast as finding an amino acid sequence for which the desired structure is the lowest energy state. As this calculation involves not only all possible amino acid sequences but also, all possible structures, most current approaches focus instead on the more tractable problem of finding the lowest-energy amino acid sequence for the desired structure, often checking by protein structure prediction in a second step that the desired structure is indeed the lowest-energy conformation for the designed sequence, and typically discarding a large fraction of designed sequences for which this is not the case. Here, we show that by backpropagating gradients through the transform-restrained Rosetta (trRosetta) structure prediction network from the desired structure to the input amino acid sequence, we can directly optimize over all possible amino acid sequences and all possible structures in a single calculation. We find that trRosetta calculations, which consider the full conformational landscape, can be more effective than Rosetta single-point energy estimations in predicting folding and stability of de novo designed proteins. We compare sequence design by conformational landscape optimization with the standard energy-based sequence design methodology in Rosetta and show that the former can result in energy landscapes with fewer alternative energy minima. We show further that more funneled energy landscapes can be designed by combining the strengths of the two approaches: the low-resolution trRosetta model serves to disfavor alternative states, and the high-resolution Rosetta model serves to create a deep energy minimum at the design target structure.


Assuntos
Redes Neurais de Computação , Proteínas/química , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Termodinâmica
8.
Int J Mol Sci ; 25(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39125776

RESUMO

Heat shock proteins (HSPs) play an important role in all living organisms under stress conditions by acting as molecular chaperones. The expression of different HSPs during stress varies depending on their protective functions and anti-apoptotic activities. The application of HSPs improves the efficiency and decreases the economic cost of animal breeding. By upregulating the expression of HSPs, feed supplements can improve stress tolerance in farm animals. In addition, high expression of HSPs is often a feature of tumor cells, and inhibiting the expression of HSPs is a promising novel method for killing these cells and treating cancers. In the present review, the findings of previous research on the application of HSPs in animal breeding and veterinary medicine are summarized, and the knowledge of the actions of HSPs in animals is briefly discussed.


Assuntos
Proteínas de Choque Térmico , Animais , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética , Cruzamento/métodos , Estresse Fisiológico , Resposta ao Choque Térmico
9.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612498

RESUMO

Sericin derived from the white cocoon of Bombyx mori has been attracting more attention for its utilization in food, cosmetics, and biomedicine. The potential health benefits of natural carotenoids for humans have also been well-established. Some rare strains of Bombyx mori (B. mori) produce yellow-red cocoons, which endow a potential of natural carotenoid-containing sericin. We hypothesized that natural carotenoid-containing sericin from yellow-red cocoons would exhibit better properties compared with white cocoon sericin. To investigate the physicochemical attributes of natural carotenoid-containing sericin, we bred two silkworm strains from one common ancestor, namely XS7 and XS8, which exhibited different cocoon colors as a result of the inconsistent distribution of lutein and ß-carotene. Compared with white cocoon sericin, the interaction between carotenoids and sericin molecules in carotenoid-containing sericin resulted in a unique fluorescence emission at 530, 564 nm. The incorporation of carotenoids enhanced the antibacterial effect, anti-cancer ability, cytocompatibility, and antioxidant of sericin, suggesting potential wide-ranging applications of natural carotenoid-containing sericin as a biomass material. We also found differences in fluorescence characteristics, antimicrobial effects, anti-cancer ability, and antioxidants between XS7 and XS8 sericin. Our work for the first time suggested a better application potential of natural carotenoid-containing sericin as a biomass material than frequently used white cocoon sericin.


Assuntos
Bombyx , Sericinas , Humanos , Animais , Carotenoides/farmacologia , Sericinas/farmacologia , Antioxidantes/farmacologia , beta Caroteno/farmacologia
10.
Anal Chem ; 95(28): 10580-10587, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37413791

RESUMO

CRISPR-Cas12a is an accurate and responsive biosensing technique, but its limited stability has restricted its widespread applications. To address this, we propose a strategy using metal-organic frameworks (MOFs) to protect Cas12a from harsh environments. After screening multiple candidate MOFs, it was found that hydrophilic MAF-7 is highly compatible with Cas12a, and the as-formed Cas12a-on-MAF-7 (COM) not only retains high enzymatic activity but also possesses excellent tolerance to heat, salt, and organic solvents. Further investigation showed that COM can serve as an analytical component for nucleic acid detection, resulting in an ultrasensitive assay for SARS-CoV-2 RNA detection with a detection limit of 1 copy. This is the first successful attempt to create an active Cas12a nanobiocomposite that functions as a biosensor without the need for shell deconstruction or enzyme release.


Assuntos
Técnicas Biossensoriais , COVID-19 , Estruturas Metalorgânicas , Humanos , COVID-19/diagnóstico , Sistemas CRISPR-Cas/genética , RNA Viral/genética , SARS-CoV-2/genética
11.
Radiology ; 306(1): 220-228, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35997608

RESUMO

Background Synovial hypoxia is a hallmark of rheumatoid arthritis (RA). Photoacoustic (PA) imaging, based on the use of laser-generated US, can detect the oxygenation status of tissue in individuals with RA. However, large studies are lacking, with few investigating the correlation between oxygenation status and disease activity. Purpose To measure synovial oxygenation status in participants with RA by using a multimodal PA US imaging system and to determine the correlation between PA imaging-measured oxygen saturation (SO2) and disease activity. Materials and Methods In this prospective observational cohort study, multimodal PA US imaging examinations were performed on small joints of consecutive participants with RA, who were treated at two outpatient rheumatology clinics from 2019 to 2021, and healthy controls. The SO2 values of the synovium were measured with dual-wavelength PA imaging and classified into three categories-hyperoxia, intermediate oxygenation status, or hypoxia-based on the signal coloration and clustering analysis of the SO2 values. The correlations of oxygenation status with power Doppler US (PDUS) scoring and clinical disease activity index were evaluated with one-way analysis of variance and the Kruskal-Wallis test with Bonferroni correction. Results A total of 118 participants with RA (median age, 55 years [IQR, 41-62 years]; 92 women) and 15 healthy control participants (median age, 37 years [IQR, 33-41 years]; 11 women) were included. The wrist synovium was categorized as hyperoxic in 36 participants with RA, of intermediate oxygenation status in 48 participants, and hypoxic in 34 participants. All control participants had hyperoxic synovial tissues. For participants with RA, hyperoxic synovium had more affluent Doppler US-depicted vasculature than those with hypoxia and intermediate oxygenation status (mean PDUS grade: hyperoxia, 2.7 ± 0.6 [SD]; intermediate, 1.3 ± 0.7; hypoxia, 1.1 ± 0.8; P < .001). Participants with intermediate status synovium had a lower clinical disease activity index than those with hypoxia (intermediate, 11.0 [IQR, 5.0-21.5] vs hypoxia, 26.0 [IQR, 18.0-39.0]; P = .001). Conclusion Photoacoustic imaging-detected hypoxia in thickened synovium correlated with less vascularization and higher disease activity in participants with rheumatoid arthritis. Clinical trial registration no. NCT04297475 © RSNA, 2022 Online supplemental material is available for this article.


Assuntos
Artrite Reumatoide , Hiperóxia , Técnicas Fotoacústicas , Sinovite , Humanos , Feminino , Pessoa de Meia-Idade , Adulto , Sinovite/tratamento farmacológico , Estudos Prospectivos , Hipóxia
12.
Small ; 19(33): e2300201, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36967560

RESUMO

Surface reconstruction of electrocatalysts is very important to clarify the structure-component-activity relationship. In this work, in situ Raman and ex situ technologies are used to capture the surface structure evolution of F-Fe-CoP during the oxygen evolution reaction (OER). The results reveal that the leaching of F accelerates the dynamic reconstruction response of CoP to rapidly convert into active (oxy)hydroxide species. The further introduction of Fe can accelerate the charge transfer rate and alleviate the structural stacking caused by insufficient kinetics. The introduction of F and Fe increases the electron occupation states of cobalt sites and promotes the adsorption of OH- ions on the CoP catalyst, which significantly improves the OER performance. F-Fe-CoP exhibits excellent OER performance with an overpotential of 259 mV at 20 mA cm-2 . This finding enriches the OER mechanism associated with the surface reconstruction of CoP and provides a reference for the rational design of efficient electrocatalysts.

13.
Electrophoresis ; 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37590395

RESUMO

Microfluidics offers a versatile and promising platform for various applications in biomedical and other fields, boasting cost-effectiveness, rapid analysis time, and a compact equipment footprint. However, achieving controlled and versatile microfluidic motion within implantable devices presents a significant challenge. In this study, we propose a novel bidirectional micro-pump design that leverages two sharp-edge microcantilever arrays, driven by ultrasound, to enable selective flow direction by manipulating the ultrasound frequency. Through systematic numerical simulation, we demonstrate the feasibility of this design and further optimize its performance through comprehensive parametric analysis. This work provides valuable guidance for the practical development of sharp-edge-based acoustic micro-pumps, particularly for potential implantable applications such as controlled drug release and in vivo sampling for advanced diagnostics.

14.
Analyst ; 148(19): 4637-4654, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37698090

RESUMO

Implantable microfluidics involves integrating microfluidic functionalities into implantable devices, such as medical implants or bioelectronic devices, revolutionizing healthcare by enabling personalized and precise diagnostics, targeted drug delivery, and regeneration of targeted tissues or organs. The impact of implantable microfluidics depends heavily on advancements in both methods and applications. Despite significant progress in the past two decades, continuous advancements are still required in fluidic control and manipulation, device miniaturization and integration, biosafety considerations, as well as the development of various application scenarios to address a wide range of healthcare issues. In this review, we discuss advancements in implantable microfluidics, focusing on methods and applications. Regarding methods, we discuss progress made in fluid manipulation, device fabrication, and biosafety considerations in implantable microfluidics. In terms of applications, we review advancements in using implantable microfluidics for drug delivery, diagnostics, tissue engineering, and energy harvesting. The purpose of this review is to expand research ideas for the development of novel implantable microfluidic devices for various healthcare applications.


Assuntos
Sistemas de Liberação de Medicamentos , Microfluídica , Dispositivos Lab-On-A-Chip , Miniaturização , Próteses e Implantes
15.
J Nanobiotechnology ; 21(1): 466, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049845

RESUMO

Xenogeneic extracellular matrices (xECM) for cell support have emerged as a potential strategy for addressing the scarcity of donor matrices for allotransplantation. However, the poor survival rate or failure of xECM-based organ transplantation is due to the negative impacts of high-level oxidative stress and inflammation on seed cell viability and stemness. Herein, we constructed xenogeneic bioengineered tooth roots (bio-roots) and used extracellular vesicles from human adipose-derived mesenchymal stem cells (hASC-EVs) to shield bio-roots from oxidative damage. Pretreatment with hASC-EVs reduced cell apoptosis, reactive oxygen species generation, mitochondrial changes, and DNA damage. Furthermore, hASC-EV treatment improved cell proliferation, antioxidant capacity, and odontogenic and osteogenic differentiation, while significantly suppressing oxidative damage by activating the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and nuclear factor erythroid 2 (NFE2)-related factor 2 (NRF2) nuclear translocation via p62-associated Kelch-like ECH-associated protein 1 (KEAP1) degradation. Inhibition of PI3K/Akt and Nrf2 knockdown reduced antioxidant capacity, indicating that the PI3K/Akt/NRF2 pathway partly mediates these effects. In subcutaneous grafting experiments using Sprague-Dawley rats, hASC-EV administration significantly enhanced the antioxidant effect of the bio-root, improved the regeneration efficiency of periodontal ligament-like tissue, and maximized xenograft function. Conclusively, therefore, hASC-EVs have the potential to be used as an immune modulator and antioxidant for treating oxidative stress-induced bio-root resorption and degradation, which may be utilized for the generation and restoration of other intricate tissues and organs.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Estresse Oxidativo , Animais , Humanos , Ratos , Antioxidantes/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Osteogênese , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
16.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38139429

RESUMO

Diabetes nephropathy (DN) is the leading cause of end-stage renal disease (ESRD) worldwide, and podocyte injury is the central contributor to the progression of DN. Despite the emerging evidence that has established the importance of podocyte endoplasmic reticulum (ER) stress in the pathogenesis of DN, abnormal protein O-GlcNAcylation is also augmented. Currently, the mechanism associating these two hyperglycemia-induced disorders remains poorly understood. This study intended to elucidate whether ER stress drives hyper-protein O-GlcNAcylation to cause podocyte injury in DN. We used both type 1 and type 2 DN models to confirm the occurrence of ER stress and excessive protein O-GlcNAcylation, and then podocyte purification was also conducted for further investigation. Nephroseq V5 data were mined and in vitro studies were applied to reveal the involvement of ER stress and hyper-O-GlcNAcylation in podocyte injury. Our results indicated that ER stress was induced in both type 1 and type 2 DN, and the human RNA-seq data from Nephroseq V5 showed that O-GlcNAcylation-related genes were significantly upregulated in the DN patients. We further demonstrated that ER stress occurred prior to hyper-O-GlcNAc modification and that pharmacologically inhibited protein O-GlcNAcylation can help decrease the podocyte apoptosis induced by hyperglycemia. Together, these discoveries will aid in uncovering the activation of the ER stress-O-GlcNAcylation axis in podocyte injury under DN, which will help open up new therapeutic approaches for preventing DN progression.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Hiperglicemia , Podócitos , Humanos , Podócitos/metabolismo , Nefropatias Diabéticas/metabolismo , Estresse do Retículo Endoplasmático/genética , Proteínas/metabolismo , Hiperglicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo
17.
BMC Neurosci ; 23(1): 72, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471242

RESUMO

BACKGROUND: To explore the feasibility of diffusion-weighted imaging (DWI) metrics to predict the histologic subtypes and genetic status of gliomas (e.g., IDH, MGMT, and TERT) noninvasively. METHODS: One hundred and eleven patients with pathologically confirmed WHO grade II-IV gliomas were recruited retrospectively. Apparent diffusion coefficient (ADC) values were measured in solid parts of gliomas on co-registered T2-weighted images and were compared with each other in terms of WHO grading and genotypes using t-tests. Receiver operating characteristic analysis was performed to assess the diagnostic performances of ADC. Subsequently, multiple linear regression was used to find independent variables, which can directly affect ADC values. RESULTS: The values of overall mean ADC (omADC) and normalized ADC (nADC) of high grade gliomas and IDH wildtype gliomas were lower than low grade gliomas and IDH mutated gliomas (P < 0.05). nADC values showed better diagnostic performance than omADC in identifying tumor grade (AUC: 0.787 vs. 0.750) and IDH status (AUC: 0.836 vs. 0.777). ADC values had limited abilities in distinguishing TERT status (AUC = 0.607 for nADC and 0.617 for omADC) and MGMT status (AUC = 0.651 for nADC). Only tumor grade and IDH status were tightly associated with ADC values. CONCLUSION: DWI metrics can predict glioma grading and IDH mutation noninvasively, but have limited use in detecting TERT mutation and MGMT methylation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Estudos Retrospectivos , Estudos de Viabilidade , Gradação de Tumores , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Organização Mundial da Saúde
18.
Eur Radiol ; 31(5): 3542-3552, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33180165

RESUMO

OBJECTIVES: We aimed to assess the clinical value of multimodal photoacoustic/ultrasound (PA/US) articular imaging scores, a novel imaging method which can reflect the micro-vessels and oxygenation level of inflamed joints of rheumatoid arthritis (RA). METHODS: Seven small joints were examined by the PA/US imaging system. A 0-3 scoring system was used to semi-quantify the PA and power-Doppler (PD) signals, and the sums of PA and PD scores (PA-sum and PD-sum scores) of the seven joints were calculated. The relative oxygen saturation (SO2) values of the inflamed joints were measured and classified into 3 PA+SO2 patterns. The correlations between the PA/US imaging scores and the disease activity scores were assessed. RESULTS: Thirty-one patients of RA and a total of 217 joints were examined using the PA/US system. The PA-sum had high positive correlations with the standard clinical scores of RA (DAS28 [ESR] ρ = 0.754, DAS28 [CRP] ρ = 0.796, SDAI ρ = 0.836, CDAI ρ = 0.837, p < 0.001), which were superior to the PD-sum (DAS28 [ESR] ρ = 0.651, DAS28 [CRP] ρ = 0.676, SDAI ρ = 0.716, CDAI ρ = 0.709, p < 0.001). For the patients with high PA-sum scores, significant differences between hypoxia and hyperoxia were identified in pain visual analog score (p = 0.020) and patient's global assessment (p = 0.026). The PA+SO2 patterns presented moderate and high correlation with PGA (ρ = 0.477, p = 0.0077) and VAS pain score (ρ = 0.717, p < 0.001). CONCLUSION: The PA scores have significant correlations with standard clinical scores for RA, and the PA+SO2 patterns are also related with clinical scores that reflect pain severity. PA may have clinical potential in evaluating RA. KEY POINTS: • Multimodal photoacoustic/ultrasound imaging is a novel method to assess micro-vessels and oxygenation of local lesions. • Significant correlations between multimodal imaging parameters and clinical scores of RA patients were verified. • The multimodal PA/US system can provide objective imaging parameters, including PA scores of micro-vessels and relative SO2 value, as a supplementary to disease activity evaluation.


Assuntos
Artrite Reumatoide , Artrite Reumatoide/diagnóstico por imagem , Humanos , Articulações/diagnóstico por imagem , Índice de Gravidade de Doença , Ultrassonografia , Ultrassonografia Doppler
19.
BMC Neurosci ; 21(1): 35, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887546

RESUMO

BACKGROUND: The inter-scanner reproducibility of brain volumetry is important in multi-site neuroimaging studies, where the reliability of automated brain segmentation (ABS) tools plays an important role. This study aimed to evaluate the influence of ABS tools on the consistency and reproducibility of the quantified brain volumetry from different scanners. METHODS: We included fifteen healthy volunteers who were scanned with 3D isotropic brain T1-weighted sequence on three different 3.0 Tesla MRI scanners (GE, Siemens and Philips). For each individual, the time span between image acquisitions on different scanners was limited to 1 h. All the T1-weighted images were processed with FreeSurfer v6.0, FSL v5.0 and AccuBrain® with default settings to obtain volumetry of brain tissues (e.g. gray matter) and substructures (e.g. basal ganglia structures) if available. Coefficient of variation (CV) was calculated to test inter-scanner variability in brain volumetry of various structures as quantified by these ABS tools. RESULTS: The mean inter-scanner CV values per brain structure among three MRI scanners ranged from 6.946 to 12.29% (mean, 9.577%) for FreeSurfer, 7.245 to 20.98% (mean, 12.60%) for FSL and 1.348 to 8.800% (mean value, 3.546%) for AccuBrain®. In addition, AccuBrain® and FreeSurfer achieved the lowest mean values of region-specific CV between GE and Siemens scanners (from 0.818 to 5.958% for AccuBrain®, and from 0.903 to 7.977% for FreeSurfer), while FSL-FIRST had the lowest mean values of region-specific CV between GE and Philips scanners (from 2.603 to 16.310%). AccuBrain® also had the lowest mean values of region-specific CV between Siemens and Philips scanners (from 1.138 to 6.615%). CONCLUSION: There is a large discrepancy in the inter-scanner reproducibility of brain volumetry when using different processing software. Image acquisition protocols and selection of ABS tool for brain volumetry quantification have impact on the robustness of results in multi-site studies.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Automação , Feminino , Voluntários Saudáveis , Humanos , Imageamento Tridimensional , Masculino , Neuroimagem/métodos , Reprodutibilidade dos Testes , Software , Adulto Jovem
20.
Mol Biol Rep ; 47(5): 4087-4091, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32246248

RESUMO

Hormones have become a useful therapeutic aspect of clinical endocrinology but how to use them to optimize the health benefits and avoid adverse effects is a major challenge. Estrogen is an indispensable hormone for proper biological functioning but is also implicated with the pathology of both the reproductive and non-reproductive tissues. Abnormal estrogen receptor signaling may increase the risk of development of a variety of diseases including colorectal cancer (CRC). Estrogen receptor beta (ERß) is the predominant subtype in the colonic epithelium and confers the anti-tumor effect through various mechanisms. Many investigators have embarked on the search for the biological mechanisms by which estrogen and estrogen-like compounds may influence the pathogenesis of CRC. This review explores the recent findings on the therapeutic role of ERß in the colonic epithelium as a prospective candidate for targeted endocrine therapy in CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/uso terapêutico , Colo/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Receptor beta de Estrogênio/uso terapêutico , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Mucosa Intestinal/metabolismo , Fitoestrógenos/metabolismo , Fitoestrógenos/farmacologia , Receptores de Estrogênio/metabolismo , Transdução de Sinais/genética
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