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1.
Nature ; 616(7957): 504-509, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37046091

RESUMO

Epstein-Barr virus (EBV) is an oncogenic herpesvirus associated with several cancers of lymphocytic and epithelial origin1-3. EBV encodes EBNA1, which binds to a cluster of 20 copies of an 18-base-pair palindromic sequence in the EBV genome4-6. EBNA1 also associates with host chromosomes at non-sequence-specific sites7, thereby enabling viral persistence. Here we show that the sequence-specific DNA-binding domain of EBNA1 binds to a cluster of tandemly repeated copies of an EBV-like, 18-base-pair imperfect palindromic sequence encompassing a region of about 21 kilobases at human chromosome 11q23. In situ visualization of the repetitive EBNA1-binding site reveals aberrant structures on mitotic chromosomes characteristic of inherently fragile DNA. We demonstrate that increasing levels of EBNA1 binding trigger dose-dependent breakage at 11q23, producing a fusogenic centromere-containing fragment and an acentric distal fragment, with both mis-segregated into micronuclei in the next cell cycles. In cells latently infected with EBV, elevating EBNA1 abundance by as little as twofold was sufficient to trigger breakage at 11q23. Examination of whole-genome sequencing of EBV-associated nasopharyngeal carcinomas revealed that structural variants are highly enriched on chromosome 11. Presence of EBV is also shown to be associated with an enrichment of chromosome 11 rearrangements across 2,439 tumours from 38 cancer types. Our results identify a previously unappreciated link between EBV and genomic instability, wherein EBNA1-induced breakage at 11q23 triggers acquisition of structural variations in chromosome 11.


Assuntos
Quebra Cromossômica , DNA , Herpesvirus Humano 4 , Proteínas Virais , Humanos , Sítios de Ligação , DNA/química , DNA/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Herpesvirus Humano 4/patogenicidade , Proteínas Virais/genética , Proteínas Virais/metabolismo , Quebras de DNA de Cadeia Dupla , Cromossomos Humanos Par 11/química , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/metabolismo , Instabilidade Genômica , Mitose
2.
Genes Dev ; 35(15-16): 1093-1108, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34266887

RESUMO

Abnormal numerical and structural chromosome content is frequently found in human cancer. To test the role of aneuploidy in tumor initiation and progression, we generated mice with random aneuploidies by transient induction of polo-like kinase 4 (Plk4), a master regulator of centrosome number. Short-term chromosome instability (CIN) from transient Plk4 induction resulted in formation of aggressive T-cell lymphomas in mice with heterozygous inactivation of one p53 allele and accelerated tumor development in the absence of p53. Transient CIN increased the frequency of lymphoma-initiating cells with a specific karyotype profile, including trisomy of chromosomes 4, 5, 14, and 15 occurring early in tumorigenesis. Tumor development in mice with chronic CIN induced by an independent mechanism (through inactivation of the spindle assembly checkpoint) gradually trended toward a similar karyotypic profile, as determined by single-cell whole-genome DNA sequencing. Overall, we show how transient CIN generates cells with random aneuploidies from which ones that acquire a karyotype with specific chromosome gains are sufficient to drive cancer formation, and that distinct CIN mechanisms can lead to similar karyotypic cancer-causing outcomes.


Assuntos
Aneuploidia , Instabilidade Cromossômica , Animais , Transformação Celular Neoplásica/genética , Centrossomo , Instabilidade Cromossômica/genética , Evolução Clonal , Instabilidade Genômica/genética , Camundongos
3.
Nature ; 591(7848): 137-141, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33361815

RESUMO

Focal chromosomal amplification contributes to the initiation of cancer by mediating overexpression of oncogenes1-3, and to the development of cancer therapy resistance by increasing the expression of genes whose action diminishes the efficacy of anti-cancer drugs. Here we used whole-genome sequencing of clonal cell isolates that developed chemotherapeutic resistance to show that chromothripsis is a major driver of circular extrachromosomal DNA (ecDNA) amplification (also known as double minutes) through mechanisms that depend on poly(ADP-ribose) polymerases (PARP) and the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). Longitudinal analyses revealed that a further increase in drug tolerance is achieved by structural evolution of ecDNAs through additional rounds of chromothripsis. In situ Hi-C sequencing showed that ecDNAs preferentially tether near chromosome ends, where they re-integrate when DNA damage is present. Intrachromosomal amplifications that formed initially under low-level drug selection underwent continuing breakage-fusion-bridge cycles, generating amplicons more than 100 megabases in length that became trapped within interphase bridges and then shattered, thereby producing micronuclei whose encapsulated ecDNAs are substrates for chromothripsis. We identified similar genome rearrangement profiles linked to localized gene amplification in human cancers with acquired drug resistance or oncogene amplifications. We propose that chromothripsis is a primary mechanism that accelerates genomic DNA rearrangement and amplification into ecDNA and enables rapid acquisition of tolerance to altered growth conditions.


Assuntos
Cromotripsia , Evolução Molecular , Amplificação de Genes/genética , Neoplasias/genética , Oncogenes/genética , Dano ao DNA , Reparo do DNA por Junção de Extremidades , DNA Circular/química , DNA Circular/metabolismo , DNA de Neoplasias/química , DNA de Neoplasias/metabolismo , Proteína Quinase Ativada por DNA , Resistencia a Medicamentos Antineoplásicos , Células HEK293 , Células HeLa , Humanos , Micronúcleos com Defeito Cromossômico , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Seleção Genética , Sequenciamento Completo do Genoma
4.
Hum Mol Genet ; 33(4): 333-341, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903058

RESUMO

Transcriptome-wide association studies (TWAS) have identified many putative susceptibility genes for colorectal cancer (CRC) risk. However, susceptibility miRNAs, critical dysregulators of gene expression, remain unexplored. We genotyped DNA samples from 313 CRC East Asian patients and performed small RNA sequencing in their normal colon tissues distant from tumors to build genetic models for predicting miRNA expression. We applied these models and data from genome-wide association studies (GWAS) including 23 942 cases and 217 267 controls of East Asian ancestry to investigate associations of predicted miRNA expression with CRC risk. Perturbation experiments separately by promoting and inhibiting miRNAs expressions and further in vitro assays in both SW480 and HCT116 cells were conducted. At a Bonferroni-corrected threshold of P < 4.5 × 10-4, we identified two putative susceptibility miRNAs, miR-1307-5p and miR-192-3p, located in regions more than 500 kb away from any GWAS-identified risk variants in CRC. We observed that a high predicted expression of miR-1307-5p was associated with increased CRC risk, while a low predicted expression of miR-192-3p was associated with increased CRC risk. Our experimental results further provide strong evidence of their susceptible roles by showing that miR-1307-5p and miR-192-3p play a regulatory role, respectively, in promoting and inhibiting CRC cell proliferation, migration, and invasion, which was consistently observed in both SW480 and HCT116 cells. Our study provides additional insights into the biological mechanisms underlying CRC development.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Transcriptoma/genética , Estudo de Associação Genômica Ampla , Neoplasias Colorretais/metabolismo , Células HCT116 , Regulação Neoplásica da Expressão Gênica/genética , Proliferação de Células/genética
5.
J Allergy Clin Immunol ; 154(4): 965-973, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38944393

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) play important roles in therapeutic applications by regulating immune responses. OBJECTIVE: We investigated the safety and efficacy of allogenic human bone marrow-derived clonal MSCs (hcMSCs) in subjects with moderate to severe atopic dermatitis (AD). METHODS: The study included a phase 1 open-label trial followed by a phase 2 randomized, double-blind, placebo-controlled trial that involved 72 subjects with moderate to severe AD. RESULTS: In phase 1, intravenous administration of hcMSCs at 2 doses (1 × 106 and 5 × 105 cells/kg) was safe and well tolerated in 20 subjects. Because there was no difference between the 2 dosage groups (P = .9), it was decided to administer low-dose hcMSCs only for phase 2. In phase 2, subjects receiving 3 weekly intravenous infusions of hcMSCs at 5 × 105 cells/kg showed a higher proportion of an Eczema Area and Severity Index (EASI)-50 response at week 12 compared to the placebo group (P = .038). The differences between groups in the Dermatology Life Quality Index and pruritus numeric rating scale scores were not statistically significant. Most adverse events were mild or moderate and resolved by the end of the study period. CONCLUSIONS: The hcMSC treatment resulted in a significantly higher rate of EASI-50 at 12 weeks compared to the control group in subjects with moderate to severe AD. The safety profile of hcMSC treatment was acceptable. Further larger-scale studies are necessary to confirm these preliminary findings.


Assuntos
Dermatite Atópica , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Dermatite Atópica/terapia , Dermatite Atópica/imunologia , Feminino , Masculino , Adulto , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Células-Tronco Mesenquimais/imunologia , Pessoa de Meia-Idade , Método Duplo-Cego , Índice de Gravidade de Doença , Adulto Jovem , Resultado do Tratamento
6.
J Biol Chem ; 299(9): 105148, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37567474

RESUMO

Mutations in sterile alpha motif domain and histidine-aspartate domain-containing protein 1 (SAMHD1) are found in a neurodevelopmental disorder, Aicardi-Goutières syndrome, and cancers, and SAMHD1, which is a deoxynucleoside triphosphate (dNTP) triphosphorylase, was identified as a myeloid-specific HIV-1 restriction factor. Here, we characterized the enzymology and structure of an SAMHD1 ortholog of Caenorhabditis elegans, ZK177.8, which also reportedly induces developmental defects upon gene knockdown. We found ZK177.8 protein is a dNTPase allosterically regulated by dGTP. The active site of ZK177.8 recognizes both 2' OH and triphosphate moieties of dNTPs but not base moiety. The dGTP activator induces the formation of the enzymatically active ZK177.8 tetramers, and ZK177.8 protein lowers cellular dNTP levels in a human monocytic cell line. Finally, ZK177.8 tetramers display very similar X-ray crystal structure with human and mouse SAMHD1s except that its lack of the canonical sterile alpha motif domain. This striking conservation in structure, function, and allosteric regulatory mechanism for the hydrolysis of the DNA building blocks supports their host developmental roles.

7.
Neuroimage ; 288: 120528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311125

RESUMO

Quantitative susceptibility mapping (QSM) is frequently employed in investigating brain iron related to brain development and diseases within deep gray matter (DGM). Nonetheless, the acquisition of whole-brain QSM data is time-intensive. An alternative approach, focusing the QSM specifically on areas of interest such as the DGM by reducing the field-of-view (FOV), can significantly decrease scan times. However, severe susceptibility value underestimations have been reported during QSM reconstruction with a limited FOV, largely attributable to artifacts from incorrect background field removal in the boundary region. This presents a considerable barrier to the clinical use of QSM with small spatial coverages using conventional methods alone. To mitigate the propagation of these errors, we proposed a harmonic field extension method based on a physics-informed generative adversarial network. Both quantitative and qualitative results demonstrate that our method outperforms conventional methods and delivers results comparable to those obtained with full FOV. Furthermore, we demonstrate the versatility of our method by applying it to data acquired prospectively with limited FOV and to data from patients with Parkinson's disease. The method has shown significant improvements in local field results, with QSM outcomes. In a clear illustration of its feasibility and effectiveness in real clinical environments, our proposed method addresses the prevalent issue of susceptibility underestimation in QSM with small spatial coverage.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos
8.
Br J Haematol ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39389908

RESUMO

The role of imatinib in PDGFRA/B-negative hypereosinophilic syndromes (HES) is controversial because of the heterogeneity of HES and the scarcity of prospective studies. We conducted a phase II clinical trial to evaluate the efficacy of imatinib in PDGFRA/B-negative HES. Thirty-two patients were treated with imatinib (100-400 mg daily), and the molecular basis of their response was identified using whole-exome sequencing (WES) and whole-transcriptome sequencing (WTS). The haematological response rate was 46.9%, with a complete haematological response (CHR) rate of 18.8%. The median time to response was 1.5 months. Among the six patients who achieved CHR, five maintained it until the 24th cycle of imatinib and one lost response after 20 months. The median progression-free survival was 4.3 months. WES and WTS were conducted for 11 patients. The number of non-silent mutations did not differ between responders and non-responders. Nine differentially expressed genes, including SNORD15A, were downregulated in responders. STAT5B::RARA, PAK2::PIGX, and FIP1L1::CHIC2 fusions were identified in patients with sustained responses, and RNF130::BRAF and WNK1::KDM5A fusions were identified in non-responders. Imatinib, along with an appropriate biomarker, could be a promising option for PDGFRA/B-negative HES.

9.
Coord Chem Rev ; 5002024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38645709

RESUMO

Photonic nanomaterials, characterized by their remarkable photonic tunability, empower a diverse range of applications, including cutting-edge advances in cancer nanomedicine. Recently, ferroptosis has emerged as a promising alternative strategy for effectively killing cancer cells with minimizing therapeutic resistance. Novel design of photonic nanomaterials that can integrate photoresponsive-ferroptosis inducers, -diagnostic imaging, and -synergistic components provide significant benefits to effectively trigger local ferroptosis. This review provides a comprehensive overview of recent advancements in photonic nanomaterials for image-guided ferroptosis cancer nanomedicine, offering insights into their strengths, constraints, and their potential as a future paradigm in cancer treatment.

10.
J Neuroinflammation ; 21(1): 224, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277768

RESUMO

BACKGROUND: Gut microbiota dysbiosis is closely associated with psychiatric disorders such as depression and anxiety (DA). In our preliminary study, fecal microbiota transplantation from volunteers with psychological stress and subclinical symptoms of depression (Vsd) induced DA-like behaviors in mice. Escherichia fergusonii (Esf) was found to be more abundant in the feces of Vsd compared to healthy volunteers. Therefore, we investigated the effect of Esf on DA-like behavior and neuroinflammation in mice with and without celiac vagotomy. METHODS AND RESULTS: Orally gavaged Esf increased DA-like behaviors, tumor necrosis factor (TNF)-α, and toll-like receptor-4 (TLR4) expression, and NF-κB+Iba1+ and lipopolysaccharide (LPS)+Iba1+ cell populations, while decreasing serotonin, 5-HT1A receptor, and brain-derived neurotrophic factor (BDNF) expression in the hippocampus and prefrontal cortex. However, celiac vagotomy attenuated Esf-induced DA-like behavior and neuroinflammation. Orally gavaged extracellular vesicle (EV) from Vsd feces (vfEV) or Esf culture (esEV) induced DA-like behavior and inflammation in hippocampus, prefrontal cortex and colon. However, celiac vagotomy attenuated vfEV- or esEV-induced DA-like behaviors and inflammation in the brain alone, while vfEV- or esEV-induced blood LPS and TNF-α levels, colonic TNF-α expression and NF-κB-positive cell number, and fecal LPS level were not. Although orally gavaged fluorescence isothiocyanate-labeled esEV was translocated into the blood and hippocampus, celiac vagotomy decreased its translocation into the hippocampus alone. CONCLUSIONS: esEVs may be translocated into the brain via the vagus nerve and bloodstream, subsequently inducing TNF-α expression and suppressing serotonin, its receptor, and BDNF expression through the activation of TLR4-mediated NF-κB signaling, thereby contributing to DA pathogenesis.


Assuntos
Depressão , Vesículas Extracelulares , Doenças Neuroinflamatórias , Nervo Vago , Animais , Camundongos , Nervo Vago/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Masculino , Doenças Neuroinflamatórias/metabolismo , Depressão/metabolismo , Depressão/etiologia , Camundongos Endogâmicos C57BL , Vagotomia
11.
Small ; 20(34): e2312249, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38618929

RESUMO

Phase-change random access memory represents a notable advancement in nonvolatile memory technology; however, it faces challenges in terms of thermal stability and reliability, hindering its broader application. To mitigate these issues, doping and structural modification techniques such as phase-change heterostructures (PCH) are widely studied. Although doping typically enhances thermal stability, it can adversely affect the switching speed. Structural modifications such as PCH have struggled to sustain stable performance under high atmospheric conditions. In this study, these challenges are addressed by synergizing oxygen-doped Sb2Te3 (OST) with PCH technology. This study presents a novel approach in which OST significantly improves the crystallization temperature, power efficiency, and cyclability. Subsequently, the integration of the PCH technology bolsters the switching speed and further amplifies the device's reliability and endurance by refining the grain size (≈7 nm). The resultant OST-PCH devices exhibit exceptional performance metrics, including a drift coefficient of 0.003 in the RESET state, endurance of ≈4 × 108 cycles, an switching speed of 300 ns, and 67.6 pJ of RESET energy. These findings suggest that the OST-PCH devices show promise for integration into embedded systems, such as those found in automotive applications and Internet of Things devices.

12.
Magn Reson Med ; 91(6): 2483-2497, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38342983

RESUMO

PURPOSE: We introduced a novel reconstruction network, jointly unrolled cross-domain optimization-based spatio-temporal reconstruction network (JUST-Net), aimed at accelerating 3D multi-echo gradient-echo (mGRE) data acquisition and improving the quality of resulting myelin water imaging (MWI) maps. METHOD: An unrolled cross-domain spatio-temporal reconstruction network was designed. The main idea is to combine frequency and spatio-temporal image feature representations and to sequentially implement convolution layers in both domains. The k-space subnetwork utilizes shared information from adjacent frames, whereas the image subnetwork applies separate convolutions in both spatial and temporal dimensions. The proposed reconstruction network was evaluated for both retrospectively and prospectively accelerated acquisition. Furthermore, it was assessed in simulation studies and real-world cases with k-space corruptions to evaluate its potential for motion artifact reduction. RESULTS: The proposed JUST-Net enabled highly reproducible and accelerated 3D mGRE acquisition for whole-brain MWI, reducing the acquisition time from fully sampled 15:23 to 2:22 min within a 3-min reconstruction time. The normalized root mean squared error of the reconstructed mGRE images increased by less than 4.0%, and the correlation coefficients for MWI showed a value of over 0.68 when compared to the fully sampled reference. Additionally, the proposed method demonstrated a mitigating effect on both simulated and clinical motion-corrupted cases. CONCLUSION: The proposed JUST-Net has demonstrated the capability to achieve high acceleration factors for 3D mGRE-based MWI, which is expected to facilitate widespread clinical applications of MWI.


Assuntos
Bainha de Mielina , Água , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Imageamento Tridimensional/métodos , Processamento de Imagem Assistida por Computador/métodos
13.
J Med Virol ; 96(1): e29361, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38178612

RESUMO

Early and accurate detection of viruses in children might help prevent transmission and severe diseases. In this study, the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) detection in children was evaluated using saliva specimens with a Proteinase K (PTK)-based RNA preparation, as saliva collection is a simple and noninvasive procedure, even in young children, with fewer concerns about sample contamination. The saliva-based PTK and the conventional paired nasopharyngeal aspiration (NPA)-based detection methods were compared between COVID-19-positive and -negative children. In addition, the detection rate for SARS-COV-2 and the difference between admission and discharge by the saliva-based PTK method was tested in COVID-19 patients. The diagnostic accuracy of the saliva-based PTK method was 98.8% compared to NP swab-based reverse transcriptase polymerase chain reaction. Saliva samples showed high sensitivity (94.1%) and specificity (100%) when using the PTK method. Furthermore, the saliva-based PTK method significantly reduced the test processing time by 2 h. Notably, Ct values at discharge increased in saliva samples compared with those at admission, which might indicate patients' clinical conditions or virus activity. In conclusion, the saliva-based PTK implemented in this study streamlines RNA extraction, making the process faster, safer, and more cost-effective, demonstrating that this method is a rapid and reliable diagnostic tool for SARS-CoV-2 detection in children.


Assuntos
COVID-19 , Saliva , Criança , Humanos , Pré-Escolar , SARS-CoV-2/genética , Endopeptidase K , COVID-19/diagnóstico , RNA , Manejo de Espécimes , Nasofaringe , Teste para COVID-19
14.
Osteoarthritis Cartilage ; 32(8): 990-1000, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38648876

RESUMO

OBJECTIVE: To examine associations between serum oxylipins, which regulate tissue repair and pain signalling, and knee pain/radiographic osteoarthritis (OA) at baseline and knee pain at 3 year follow-up. METHOD: Baseline, and 3 year follow-up, knee pain phenotypes were assessed from 154 participants in the Knee Pain in the Community (KPIC) cohort study. Serum and radiographic Kellgren and Lawrence (KL) and Nottingham line drawing atlas OA scores were collected at baseline. Oxylipin levels were quantified using liquid chromatography coupled with mass spectrometry. Associations were measured by linear regression and receiver operating characteristics (ROC). RESULTS: Serum levels of 8,9-epoxyeicosatrienoic acid (EET) (ß(95% confidence intervals (CI)) = 1.809 (-0.71 to 2.91)), 14,15-dihydroxyeicosatrienoic acid (DHET) (ß(95%CI) = 0.827 (0.34-1.31)), and 12-hydroxyeicosatetraenoic acid (HETE) (ß(95%CI) = 4.090 (1.92-6.26)) and anandamide (ß(95%CI) = 3.060 (1.35-4.77)) were cross-sectionally associated with current self-reported knee pain scores (numerical rating scale (NRS) item 3, average pain). Serum levels of 9- (ß(95%CI) = 0.467 (0.18-0.75)) and 15-HETE (ß(95%CI) = 0.759 (0.29-1.22)), 14-hydroxydocosahexaenoic acid (ß(95%CI) = 0.483(0.24-0.73)), and the ratio of 8,9-EET:DHET (ß(95%CI) = 0.510(0.19-0.82)) were cross-sectionally associated with KL scores. Baseline serum concentrations of 8,9-EET (ß(95%CI) = 2.166 (0.89-3.44)), 5,6-DHET (ß(95%CI) = 152.179 (69.39-234.97)), and 5-HETE (ß(95%CI) = 1.724 (0.677-2.77) showed positive longitudinal associations with follow-up knee pain scores (NRS item 3, average pain). Combined serum 8,9-EET and 5-HETE concentration showed the strongest longitudinal association (ß(95%CI) = 1.156 (0.54-1.77) with pain scores at 3 years, and ROC curves distinguished between participants with no pain and high pain scores at follow-up (area under curve (95%CI) = 0.71 (0.61-0.82)). CONCLUSIONS: Serum levels of a combination of hydroxylated metabolites of arachidonic acid may have prognostic utility for knee pain, providing a potential novel approach to identify people who are more likely to have debilitating pain in the future.


Assuntos
Artralgia , Progressão da Doença , Osteoartrite do Joelho , Humanos , Feminino , Masculino , Osteoartrite do Joelho/sangue , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Artralgia/sangue , Estudos Longitudinais , Estudos de Coortes , Oxilipinas/sangue , Articulação do Joelho , Ácidos Hidroxieicosatetraenoicos/sangue , Ácidos Araquidônicos/sangue , Biomarcadores/sangue , Medição da Dor , Ácido Araquidônico/sangue
15.
Blood ; 139(22): 3325-3339, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35226727

RESUMO

We previously demonstrated that interferon γ (IFN-γ) derived from donor T cells co-opts the indoleamine 2,3-dioxygenase 1 (IDO1) → aryl hydrocarbon receptor (AHR) axis to suppress idiopathic pneumonia syndrome (IPS). Here we report that the dysregulated expression of AP-1 family genes in Ahr-/- lung epithelial cells exacerbated IPS in allogeneic bone marrow transplantation settings. AHR repressed transcription of Jund by preventing STAT1 from binding to its promoter. As a consequence, decreased interleukin-6 impaired the differentiation of CD4+ T cells toward Th17 cells. IFN-γ- and IDO1-independent induction of Ahr expression indicated that the AHR agonist might be a better therapeutic target for IPS than the IDO1 activator. We developed a novel synthetic AHR agonist (referred to here as PB502) that potently inhibits Jund expression. PB502 was highly effective at inducing AHR activation and ameliorating IPS. Notably, PB502 was by far superior to the endogenous AHR ligand, L-kynurenine, in promoting the differentiation of both mouse and human FoxP3+ regulatory CD4+ T cells. Our results suggest that the IDO1-AHR axis in lung epithelial cells is associated with IPS repression. A specific AHR agonist may exhibit therapeutic activity against inflammatory and autoimmune diseases by promoting regulatory T-cell differentiation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Pneumonia , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Interferon gama/metabolismo , Camundongos , Pneumonia/tratamento farmacológico , Transdução de Sinais , Linfócitos T Reguladores/metabolismo
16.
J Magn Reson Imaging ; 59(4): 1218-1228, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37477575

RESUMO

BACKGROUND: While breast ultrasound (US) is a useful tool for diagnosing breast masses, it can entail false-positive biopsy results because of some overlapping features between benign and malignant breast masses and subjective interpretation. PURPOSE: To evaluate the performance of conductivity imaging for reducing false-positive biopsy results related to breast US, as compared to diffusion-weighted imaging (DWI) and abbreviated MRI consisting of one pre- and one post-contrast T1-weighted imaging. STUDY TYPE: Prospective. SUBJECTS: Seventy-nine women (median age, 44 years) with 86 Breast Imaging Reporting and Data System (BI-RADS) category 4 masses as detected by breast US. FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted turbo spin echo sequence, DWI, and abbreviated contrast-enhanced MRI (T1-weighted gradient echo sequence). ASSESSMENT: US-guided biopsy (reference standard) was obtained on the same day as MRI. The maximum and mean conductivity parameters from whole and single regions of interest (ROIs) were measured. Apparent diffusion coefficient (ADC) values were obtained from an area with the lowest signal within a lesion on the ADC map. The performance of conductivity, ADC, and abbreviated MRI for reducing false-positive biopsies was evaluated using the following criteria: lowest conductivity and highest ADC values among malignant breast lesions and BI-RADS categories 2 or 3 on abbreviated MRI. STATISTICAL TESTS: One conductivity parameter with the maximum area under the curve (AUC) from receiver operating characteristics was selected. A P-value <0.05 was considered statistically significant. RESULTS: US-guided biopsy revealed 65 benign lesions and 21 malignant lesions. The mean conductivity parameter of the single ROI method was selected (AUC = 0.74). Considering conductivity (≤0.10 S/m), ADC (≥1.60 × 10-3 mm2 /sec), and BI-RADS categories 2 or 3 reduced false-positive biopsies by 23% (15 of 65), 38% (25 of 65), and 43% (28 of 65), respectively, without missing malignant lesions. DATA CONCLUSION: Conductivity imaging may show lower performance than DWI and abbreviated MRI in reducing unnecessary biopsies. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Meios de Contraste , Feminino , Humanos , Adulto , Estudos Prospectivos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Biópsia , Biópsia Guiada por Imagem , Diagnóstico Diferencial , Neoplasias da Mama/diagnóstico por imagem , Sensibilidade e Especificidade
17.
Brain Behav Immun ; 118: 136-148, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428648

RESUMO

Gut microbiota communicates bidirectionally with the brain through the nervous, immune, and endocrine systems of the gut. In our preliminary study, the fecal microbiota of volunteers with mild cognitive impairment (Fmci) exhibited a higher abundance of Escherichia fergusonii (NK2001), Veillonella infantium (NK2002), and Enterococcus faecium (NK2003) populations compared with those of healthy volunteers. Therefore, we examined the effects of Fmci, NK2001 (gram-negative), NK2002 (gram-negative-like), and NK2003 (gram-positive) on cognitive impairment-like behavior, neuroinflammation, and colitis in mice with or without antibiotics. Fmci transplantation increased cognitive impairment-like behavior, hippocampal tumor necrosis factor (TNF)-α expression, and the size of toll-like receptor (TLR)4+Iba1+, TLR2+Iba1+, and NF-κB+Iba1+ cell populations independent of antibiotic treatment. Oral gavage of NK2001, NK2002, or NK2003, which induced TNF-α expression in Caco-2 cells, significantly increased cognitive impairment-like behavior and hippocampal TNF-α expression and Iba1-positive cell populations and decreased brain-derived neurotrophic factor (BDNF) expression in mice. Celiac vagotomy significantly decreased NK2001- or NK2002-induced cognitive impairment-like behavior and hippocampal Iba1+ cell population and TNF-α expression and increased NK2001- or NK2002-suppressed hippocampal BDNF expression. However, NK2003-induced cognitive impairment-like behavior and hippocampal Iba1+ cell population and TNF-α expression were partially, but not significantly, attenuated by celiac vagotomy. Furthermore, celiac vagotomy did not affect NK2001-, NK2002-, or NK2003-induced lipopolysaccharide (LPS) levels in the blood and feces and TNF-α expression and NF-κB-positive cell population in the colon. In conclusion, LPS-producing NK2001 and NK2002 and LPS-nonproducing NK2003 may induce NF-κB-mediated neuroinflammation through the translocation of byproducts such as LPS and peptidoglycan into the brain through gut-blood/vagus nerve-brain and gut-blood-brain pathways, respectively, resulting in cognitive impairment.


Assuntos
Disfunção Cognitiva , Escherichia , Lipopolissacarídeos , Veillonella , Humanos , Camundongos , Animais , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Fator Neurotrófico Derivado do Encéfalo , Fator de Necrose Tumoral alfa/metabolismo , Doenças Neuroinflamatórias , Células CACO-2 , Nervo Vago , Camundongos Endogâmicos C57BL
18.
Mol Pharm ; 21(10): 5005-5014, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39169803

RESUMO

Biodegradable radioactive microspheres labeled with positron emitters hold significant promise for diagnostic and therapeutic applications in cancers and other diseases, including arthritis. The alginate-based polymeric microspheres offer advantages such as biocompatibility, biodegradability, and improved stability, making them suitable for clinical applications. In this study, we developed novel positron emission tomography (PET) microspheres using alginate biopolymer radiolabeled with gallium-68 (68Ga) through a straightforward conjugation reaction. Polyethylenimine (PEI)-decorated calcium alginate microspheres (PEI-CAMSs) were fabricated and further modified using azadibenzocyclooctyne-N-hydroxysuccinimide ester (ADIBO-NHS). Subsequently, azide-functionalized NOTA chelator (N3-NOTA) was labeled with [68Ga]Ga to obtain [68Ga]Ga-NOTA-N3, which was then reacted with the surface-modified PEI-CAMSs using strain-promoted alkyne-azide cycloaddition (SPAAC) reaction to develop [68Ga]Ga-NOTA-PEI-CAMSs, a novel PET microsphere. The radiolabeling efficiency and radiochemical stability of [68Ga]Ga-NOTA-PEI-CAMSs were determined using the radio-instant thin-layer chromatography-silica gel (radio-ITLC-SG) method. The in vivo PET images were also acquired to study the in vivo stability of the radiolabeled microspheres in normal mice. The radiolabeling efficiency of [68Ga]Ga-NOTA-PEI-CAMSs was over 99%, and the microspheres exhibited high stability (92%) in human blood serum. PET images demonstrated the stability and biodistribution of the microspheres in mice for up to 2 h post injection. This study highlights the potential of biodegradable PET microspheres for preoperative imaging and targeted radionuclide therapy. Overall, the straightforward synthesis method and efficient radiolabeling technique provide a promising platform for the development of theranostic microspheres using other radionuclides such as 90Y, 177Lu, 188Re, and 64Cu.


Assuntos
Alginatos , Química Click , Radioisótopos de Gálio , Microesferas , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Alginatos/química , Animais , Química Click/métodos , Radioisótopos de Gálio/química , Camundongos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual , Humanos , Quelantes/química
19.
Liver Int ; 44(10): 2615-2624, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39011563

RESUMO

BACKGROUND: Socioeconomic status (SES) is a driver of health disparities and chronic diseases. People with HIV (PWH) are at risk for chronic liver diseases. We evaluated the association between low SES and hepatic outcomes in PWH. METHODS: We included PWH from a prospective cohort. SES was assessed by the Pampalon material and social deprivation index to classify the cohort into quintiles of deprivation. Multivariable linear regression was used to investigate associations of material and social deprivation with liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) as markers of hepatic fibrosis and steatosis, respectively. Incidence of outcomes was evaluated through survival analysis. RESULTS: Among the 804 PWH included, 45% and 72% were living in areas of the highest material and social deprivation, respectively. Materially deprived PWH were more frequently female and of non-white ethnicity and had higher prevalence of metabolic comorbidities. After adjustments, material deprivation correlated with increased LSM (ß = 1.86, 95% CI 0.53-3.17) but not with CAP (ß = 6.47, 95% CI -5.55-18.49). Patients were observed for a median follow-up of 3.8 years. Incidence of liver-related events was higher in most materially deprived compared to most privileged PWH (hazard ratio 3.03, 95% CI 1.03-8.92), while there was no difference in extrahepatic outcomes or all-cause mortality. Social deprivation showed no association with either LSM or clinical outcomes. CONCLUSIONS: Living in materially deprived neighbourhoods as a proxy for lower SES, is associated with LSM and liver-related events in PWH. Future strategies should explore mechanisms underlying these relationships and whether enhanced material security improves hepatic outcomes.


Assuntos
Infecções por HIV , Cirrose Hepática , Humanos , Feminino , Masculino , Infecções por HIV/complicações , Estudos Prospectivos , Pessoa de Meia-Idade , Adulto , Técnicas de Imagem por Elasticidade , Classe Social , Fígado/patologia , Incidência , Modelos Lineares , Fatores de Risco , Análise Multivariada , Disparidades nos Níveis de Saúde
20.
J Sleep Res ; 33(1): e14050, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37752626

RESUMO

Given the significant impact of sleep on overall health, radar technology offers a promising, non-invasive, and cost-effective avenue for the early detection of sleep disorders, even prior to relying on polysomnography (PSG)-based classification. In this study, we employed an attention-based bidirectional long short-term memory (Attention Bi-LSTM) model to accurately predict sleep stages using 60 GHz frequency-modulated continuous-wave (FMCW) radar. Our dataset comprised 78 participants from an ongoing obstructive sleep apnea (OSA) cohort, recruited between July 2021 and November 2022, who underwent overnight polysomnography alongside radar sensor monitoring. The dataset encompasses comprehensive polysomnography recordings, spanning both sleep and wakefulness states. The predictions achieved a Cohen's kappa coefficient of 0.746 and an overall accuracy of 85.2% in classifying wakefulness, rapid-eye-movement (REM) sleep, and non-REM (NREM) sleep (N1 + N2 + N3). The results demonstrated that the models incorporating both Radar 1 and Radar 2 data consistently outperformed those using only Radar 1 data, indicating the potential benefits of utilising multiple radars for sleep stage classification. Although the performance of the models tended to decline with increasing OSA severity, the addition of Radar 2 data notably improved the classification accuracy. These findings demonstrate the potential of radar technology as a valuable screening tool for sleep stage classification.


Assuntos
Aprendizado Profundo , Apneia Obstrutiva do Sono , Humanos , Radar , Fases do Sono , Apneia Obstrutiva do Sono/diagnóstico , Sono
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