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1.
PLoS Pathog ; 20(6): e1012271, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829910

RESUMO

Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in many biological processes, and epigenomic analysis is used to determine the involved enhancers and transcription factors. To determine new transcription factors in anti-DNA-virus response, we have performed H3K27ac ChIP-Seq and identified three transcription factors, NR2F6, MEF2D and MAFF, in promoting HSV-1 replication. NR2F6 promotes HSV-1 replication and gene expression in vitro and in vivo, but not dependent on cGAS/STING pathway. NR2F6 binds to the promoter of MAP3K5 and activates AP-1/c-Jun pathway, which is critical for DNA virus replication. On the other hand, NR2F6 is transcriptionally repressed by c-Jun and forms a negative feedback loop. Meanwhile, cGAS/STING innate immunity signaling represses NR2F6 through STAT3. Taken together, we have identified new transcription factors and revealed the underlying mechanisms involved in the network between DNA viruses and host cells.


Assuntos
Herpesvirus Humano 1 , Imunidade Inata , Humanos , Animais , Herpesvirus Humano 1/imunologia , Camundongos , Replicação Viral , Herpes Simples/imunologia , Herpes Simples/virologia , Herpes Simples/metabolismo , Transdução de Sinais , Células HEK293 , Proteínas Repressoras
2.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34571533

RESUMO

Cancer stem cells (CSCs) actively reprogram their tumor microenvironment (TME) to sustain a supportive niche, which may have a dramatic impact on prognosis and immunotherapy. However, our knowledge of the landscape of the gastric cancer stem-like cell (GCSC) microenvironment needs to be further improved. A multi-step process of machine learning approaches was performed to develop and validate the prognostic and predictive potential of the GCSC-related score (GCScore). The high GCScore subgroup was not only associated with stem cell characteristics, but also with a potential immune escape mechanism. Furthermore, we experimentally demonstrated the upregulated infiltration of CD206+ tumor-associated macrophages (TAMs) in the invasive margin region, which in turn maintained the stem cell properties of tumor cells. Finally, we proposed that the GCScore showed a robust capacity for prediction for immunotherapy, and investigated potential therapeutic targets and compounds for patients with a high GCScore. The results indicate that the proposed GCScore can be a promising predictor of prognosis and responses to immunotherapy, which provides new strategies for the precision treatment of GCSCs.


Assuntos
Neoplasias Gástricas , Humanos , Imunoterapia/métodos , Células-Tronco Neoplásicas/patologia , Farmacogenética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Microambiente Tumoral
3.
Eur J Nucl Med Mol Imaging ; 51(4): 1012-1022, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37955791

RESUMO

PURPOSE: Aging is a major societal concern due to age-related functional losses. Synapses are crucial components of neural circuits, and synaptic density could be a sensitive biomarker to evaluate brain function. [11C]UCB-J is a positron emission tomography (PET) ligand targeting synaptic vesicle glycoprotein 2A (SV2A), which can be used to evaluate brain synaptic density in vivo. METHODS: We evaluated age-related changes in gray matter synaptic density, volume, and blood flow using [11C]UCB-J PET and magnetic resonance imaging (MRI) in a wide age range of 80 cognitive normal subjects (21-83 years old). Partial volume correction was applied to the PET data. RESULTS: Significant age-related decreases were found in 13, two, and nine brain regions for volume, synaptic density, and blood flow, respectively. The prefrontal cortex showed the largest volume decline (4.9% reduction per decade: RPD), while the synaptic density loss was largest in the caudate (3.6% RPD) and medial occipital cortex (3.4% RPD). The reductions in caudate are consistent with previous SV2A PET studies and likely reflect that caudate is the site of nerve terminals for multiple major tracts that undergo substantial age-related neurodegeneration. There was a non-significant negative relationship between volume and synaptic density reductions in 16 gray matter regions. CONCLUSION: MRI and [11]C-UCB-J PET showed age-related decreases of gray matter volume, synaptic density, and blood flow; however, the regional patterns of the reductions in volume and SV2A binding were different. Those patterns suggest that MR-based measures of GM volume may not be directly representative of synaptic density.


Assuntos
Substância Cinzenta , Glicoproteínas de Membrana , Humanos , Idoso de 80 Anos ou mais , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/metabolismo , Glicoproteínas de Membrana/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Sinapses/metabolismo
4.
Am J Geriatr Psychiatry ; 32(1): 17-28, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37673749

RESUMO

OBJECTIVE: Multimodal imaging techniques have furthered our understanding of how different aspects of Alzheimer's disease (AD) pathology relate to one another. Diffusion tensor imaging (DTI) measures such as mean diffusivity (MD) may be a surrogate measure of the changes in gray matter structure associated with AD. Positron emission tomography (PET) imaging of synaptic vesicle glycoprotein 2A (SV2A) has been used to quantify synaptic loss, which is the major pathological correlate of cognitive impairment in AD. In this study, we investigated the relationship between gray matter microstructure and synaptic density. METHODS: DTI was used to measure MD and [11C]UCB-J PET to measure synaptic density in 33 amyloid-positive participants with AD and 17 amyloid-negative cognitively normal (CN) participants aged 50-83. Univariate regression analyses were used to assess the association between synaptic density and MD in both the AD and CN groups. RESULTS: Hippocampal MD was inversely associated with hippocampal synaptic density in participants with AD (r = -0.55, p <0.001, df = 31) but not CN (r = 0.13, p = 0.62, df = 15). Exploratory analyses across other regions known to be affected in AD suggested widespread inverse associations between synaptic density and MD in the AD group. CONCLUSION: In the setting of AD, an increase in gray matter MD is inversely associated with synaptic density. These co-occurring changes may suggest a link between synaptic loss and gray matter microstructural changes in AD. Imaging studies of gray matter microstructure and synaptic density may allow important insights into AD-related neuropathology.


Assuntos
Doença de Alzheimer , Substância Branca , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Imagem de Tensor de Difusão , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Tomografia por Emissão de Pósitrons/métodos , Imagem Multimodal , Encéfalo/metabolismo , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso/metabolismo
5.
BMC Anesthesiol ; 24(1): 121, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38539078

RESUMO

INTRODUCTION: Postoperative nausea and vomiting (PONV) is one of the most common adverse events following orthognathic surgery. It's a distressing feeling for patients and continues to be the cause of postoperative complications such as bleeding, delayed healing, and wound infection. This scoping review aims to identify effective PONV prophylaxis strategies during orthognathic surgery that have emerged in the past 15 years. METHODS: We searched Pubmed, Cochrane Controlled Register of Trials, and Embase from 2008 to May 2023. Studies meeting the following criteria were eligible for inclusion: (1) recruited patients undergo any orthognathic surgery; (2) evaluated any pharmacologic or non-pharmacologic method to prevent PONV. Studies meeting the following criteria were excluded: (1) case series, review papers, or retrospective studies; (2) did not report our prespecified outcomes. RESULTS: Twenty-one studies were included in this review. Pharmacological methods for PONV prevention include ondansetron and dexamethasone (3 studies), peripheral nerve block technique (4 studies), dexmedetomidine (1 study), pregabalin (2 studies), nefopam (2 studies), remifentanil (1 study), propofol (2 studies), and penehyclidine (1 study). Non-pharmacologic methods include capsicum plaster (1 study), throat packs (2 studies) and gastric aspiration (2 studies). CONCLUSIONS: Based on current evidence, we conclude that prophylactic antiemetics like dexamethasone, ondansetron, and penehyclidine are the first defense against PONV. Multimodal analgesia with nerve block techniques and non-opioid analgesics should be considered due to their notable opioid-sparing and PONV preventive effect. For the non-pharmacological methods, throat packs are not recommended for routine use because of their poor effect and serious complications. More prospective RCTs are required to confirm whether gastric aspiration can prevent PONV effectively for patients undergoing orthognathic surgery.


Assuntos
Antieméticos , Cirurgia Ortognática , Humanos , Náusea e Vômito Pós-Operatórios/prevenção & controle , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Ondansetron/uso terapêutico , Estudos Prospectivos , Estudos Retrospectivos , Antieméticos/uso terapêutico , Dexametasona/uso terapêutico
6.
Int J Mol Sci ; 25(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38999981

RESUMO

The interferon regulatory factors (IRFs) family comprises 11 members that are involved in various biological processes such as antiviral defense, cell proliferation regulation, differentiation, and apoptosis. Recent studies have highlighted the roles of IRF1-9 in a range of liver diseases, including hepatic ischemia-reperfusion injury (IRI), alcohol-induced liver injury, Con A-induced liver injury, nonalcoholic fatty liver disease (NAFLD), cirrhosis, and hepatocellular carcinoma (HCC). IRF1 is involved in the progression of hepatic IRI through signaling pathways such as PIAS1/NFATc1/HDAC1/IRF1/p38 MAPK and IRF1/JNK. The regulation of downstream IL-12, IL-15, p21, p38, HMGB1, JNK, Beclin1, ß-catenin, caspase 3, caspase 8, IFN-γ, IFN-ß and other genes are involved in the progression of hepatic IRI, and in the development of HCC through the regulation of PD-L1, IL-6, IL-8, CXCL1, CXCL10, and CXCR3. In addition, IRF3-PPP2R1B and IRF4-FSTL1-DIP2A/CD14 pathways are involved in the development of NAFLD. Other members of the IRF family also play moderately important functions in different liver diseases. Therefore, given the significance of IRFs in liver diseases and the lack of a comprehensive compilation of their molecular mechanisms in different liver diseases, this review is dedicated to exploring the molecular mechanisms of IRFs in various liver diseases.


Assuntos
Fatores Reguladores de Interferon , Hepatopatias , Humanos , Hepatopatias/metabolismo , Hepatopatias/patologia , Hepatopatias/genética , Animais , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/genética , Transdução de Sinais
7.
J Am Chem Soc ; 145(22): 12193-12205, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37208802

RESUMO

Selenoprotein plays a crucial role in immune cells and inflammatory regulation. However, as a protein drug that is easily denatured or degraded in the acidic environment of the stomach, efficient oral delivery of selenoprotein is a great challenge. Herein, we innovated an oral hydrogel microbeads-based biochemical strategy that can in situ synthesize selenoproteins, therefore bypassing the necessity and harsh conditions for oral protein delivery while effectively generating selenoproteins for therapeutic applications. The hydrogel microbeads were synthesized by coating hyaluronic acid-modified selenium nanoparticles with a protective shell of calcium alginate (SA) hydrogel. We tested this strategy in mice with inflammatory bowel disease (IBD), one of the most representative diseases related to intestinal immunity and microbiota. Our results revealed that hydrogel microbeads-mediated in situ synthesis of selenoproteins could prominently reduce proinflammatory cytokines secretion and mediate immune cells (e.g., reduce neutrophils and monocytes and increase immune regulatory T cells) to effectively relieve colitis-associated symptoms. This strategy was also able to regulate gut microbiota composition (increase probiotics abundance and suppress detrimental communities) to maintain intestinal homeostasis. Considering intestinal immunity and microbiota widely associated with cancers, infections, inflammations, etc., this in situ selenoprotein synthesis strategy might also be possibly applied to broadly tackle various diseases.


Assuntos
Hidrogéis , Microbiota , Animais , Camundongos , Microesferas , Selenoproteínas/metabolismo , Inflamação
8.
Curr Issues Mol Biol ; 45(4): 3640-3657, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37185761

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease with multifactorial pathogenesis; histone demethylases (HDMs) are emerging as attractive targets. We identified HDM genes (including KDM5C, KDM6B, KDM8, KDM4A, and JMJD7) that were differentially expressed in NAFLD and normal samples by exploring gene expression profiling datasets. There was no significant difference in the expression of genes related to histone demethylation between mild and advanced NAFLD. In vitro and in vivo studies indicated that KDM6B and JMJD7 were upregulated at the mRNA level in NAFLD. We explored the expression levels and prognostic values of the identified HDM genes in hepatocellular carcinoma (HCC). KDM5C and KDM4A were upregulated in HCC compared to normal tissue, while KDM8 showed downregulation. The abnormal expression levels of these HDMs could provide prognostic values. Furthermore, KDM5C and KDM4A were associated with immune cell infiltration in HCC. HDMs were associated with cellular and metabolic processes and may be involved in the regulation of gene expression. Differentially expressed HDM genes identified in NAFLD may provide value to understanding pathogenesis and in the development of epigenetic therapeutic targets. However, on the basis of the inconsistent results of in vitro studies, future in vivo experiments combined with transcriptomic analysis are needed for further validation.

9.
Hepatology ; 76(3): 576-588, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35073427

RESUMO

BACKGROUND AND AIMS: The incidence of HCC has recently been consistently reported to decline in the United States. However, decreased overall mortality of HCC has just been suggested and needs further examination. APPROACH AND RESULTS: Using data from the Surveillance, Epidemiology, and End Results databases, we assessed HCC incidence, incidence-based mortality (IBM), and 1-year survival rates from 1992 through 2017 in the United States. These secular trends were analyzed using the National Cancer Institute's Joinpoint Regression Program. Age-period-cohort analyses were performed to address underlying reasons for the observed temporal trends. The incidence and mortality of liver cancer in the United States by different etiologies were acquired from the Global Burden of Disease study (1990-2019) as a likely validation set. Joinpoint and age-period-cohort analyses were performed by etiologies. The incidence rates of HCC increased during 1992-2011 and sharply decreased thereafter by -2.3% annually (95% CI: -3.5% to -1.1%). IBM peaked in 2013 (age-standardized mortality rate: 6.98 per 100,000 person-years) in the US population. IBM started to decrease significantly in 2013 by -3.2%/year (95% CI: -5.4% to -1.1% per year) after a continuous increase of 3.5% annually during 1993-2013. Overall, the 1-year survival of HCC improved from 21.4% to 56.6% over the study period. However, the highest HCC incidence and mortality risk for patients aged 60-69 and born between 1952-1957 were found. CONCLUSIONS: We found significantly decreased overall HCC-specific mortality since 2013 in the US population, along with decreased incidence and continuously improved survival. The changing etiologies, advances in screening and diagnosis, and improved treatment modality and allocation might all contribute to the downward trends of the disease burden of HCC in the United States.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/epidemiologia , Efeitos Psicossociais da Doença , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Programa de SEER , Estados Unidos/epidemiologia
10.
J Gastroenterol Hepatol ; 38(8): 1426-1437, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37332142

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. The detailed epigenomic changes during fat accumulation in liver are not clear yet. Here, we performed ChIP-Seq analysis in the liver tissues of high-fat diet and regular chow diet mice and investigated the dynamic landscapes of H3K27ac and H3K9me3 marks on chromatin. We find that the activated typical enhancers marked with H3K27ac are enriched on lipid metabolic pathways in fat liver; however, super enhancers do not change much. The regions covered with H3K9me3 repressive mark seem to undergo great changes, and its peak number and intensity both decrease in fat liver. The enhancers located in lost H3K9me3 regions are enriched in lipid metabolism and inflammatory pathways; and motif analysis shows that they are potential targets for transcription factors involved in metabolic and inflammatory processes. Our study has revealed that H3K9me3 may play an important role during the pathogenesis of NAFLD through regulating the accessibility of enhancers.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Metabolismo dos Lipídeos/genética , Epigênese Genética
11.
J Am Chem Soc ; 144(45): 20825-20833, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36318653

RESUMO

Thioredoxin reductase (TrxR) is highly overexpressed in cancer cells to promote malignant tumor survival. Designing drugs that inhibit TrxR activity is a promising approach to achieve highly effective cancer chemotherapy. However, the selectivity of TrxR inhibitors continue to be a challenge for scientists. In this work, we demonstrate a new strategy to selectively inhibit TrxR through constructing electrophilic center -N-Se(δ+)-N- by using the polarization effect of the selenium atom. The constructed electrophilic center interacts noncovalently with the active motif of TrxR to avoid the interference of other residues in human tissues, thereby selectively inhibiting intracellular TrxR activity. Computational and experimental analysis confirms that the formed electrophilic selenium center preferred to attack the SeC residues in the redox active center of TrxR at the 498 site through strong noncovalent interactions. Both in vitro and in vivo experimental results confirmed that this strategy can significantly improve the anticancer effect. This study may provide a novel route to design highly effective and selective chemotherapeutic drugs.


Assuntos
Neoplasias , Selênio , Humanos , Tiorredoxina Dissulfeto Redutase , Selênio/farmacologia , Neoplasias/tratamento farmacológico , Oxirredução , Antioxidantes
12.
Eur J Nucl Med Mol Imaging ; 49(9): 3086-3097, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35277742

RESUMO

A novel deep learning (DL)-based attenuation correction (AC) framework was applied to clinical whole-body oncology studies using 18F-FDG, 68 Ga-DOTATATE, and 18F-Fluciclovine. The framework used activity (λ-MLAA) and attenuation (µ-MLAA) maps estimated by the maximum likelihood reconstruction of activity and attenuation (MLAA) algorithm as inputs to a modified U-net neural network with a novel imaging physics-based loss function to learn a CT-derived attenuation map (µ-CT). METHODS: Clinical whole-body PET/CT datasets of 18F-FDG (N = 113), 68 Ga-DOTATATE (N = 76), and 18F-Fluciclovine (N = 90) were used to train and test tracer-specific neural networks. For each tracer, forty subjects were used to train the neural network to predict attenuation maps (µ-DL). µ-DL and µ-MLAA were compared to the gold-standard µ-CT. PET images reconstructed using the OSEM algorithm with µ-DL (OSEMDL) and µ-MLAA (OSEMMLAA) were compared to the CT-based reconstruction (OSEMCT). Tumor regions of interest were segmented by two radiologists and tumor SUV and volume measures were reported, as well as evaluation using conventional image analysis metrics. RESULTS: µ-DL yielded high resolution and fine detail recovery of the attenuation map, which was superior in quality as compared to µ-MLAA in all metrics for all tracers. Using OSEMCT as the gold-standard, OSEMDL provided more accurate tumor quantification than OSEMMLAA for all three tracers, e.g., error in SUVmax for OSEMMLAA vs. OSEMDL: - 3.6 ± 4.4% vs. - 1.7 ± 4.5% for 18F-FDG (N = 152), - 4.3 ± 5.1% vs. 0.4 ± 2.8% for 68 Ga-DOTATATE (N = 70), and - 7.3 ± 2.9% vs. - 2.8 ± 2.3% for 18F-Fluciclovine (N = 44). OSEMDL also yielded more accurate tumor volume measures than OSEMMLAA, i.e., - 8.4 ± 14.5% (OSEMMLAA) vs. - 3.0 ± 15.0% for 18F-FDG, - 14.1 ± 19.7% vs. 1.8 ± 11.6% for 68 Ga-DOTATATE, and - 15.9 ± 9.1% vs. - 6.4 ± 6.4% for 18F-Fluciclovine. CONCLUSIONS: The proposed framework provides accurate and robust attenuation correction for whole-body 18F-FDG, 68 Ga-DOTATATE and 18F-Fluciclovine in tumor SUV measures as well as tumor volume estimation. The proposed method provides clinically equivalent quality as compared to CT in attenuation correction for the three tracers.


Assuntos
Aprendizado Profundo , Neoplasias , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Cintilografia , Compostos Radiofarmacêuticos
13.
FASEB J ; 35(9): e21667, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34405442

RESUMO

Long noncoding RNAs (lncRNAs) are central regulators of the inflammatory response and play an important role in inflammatory diseases. PINT has been reported to be involved in embryonic development and tumorigenesis. However, the potential functions of PINT in the innate immune system are largely unknown. Here, we revealed the transcriptional regulation of inflammatory genes by PINT, whose expression is primarily dependent on the NF-κB signaling pathway in human and mouse macrophage and intestinal epithelial cell lines. Functionally, PINT selectively regulates the expression of TNF-α in basal and LPS-stimulated cells. Mechanistically, PINT acts as a modular scaffold of p65 and EZH2 to coordinate their localization and specify their binding to the target genes. Further, a high expression level of PINT was detected in intestinal mucosal tissues from patients with ulcerative colitis (UC). Together, these findings demonstrate that PINT acts as an activator of inflammatory responses, highlighting the importance of this lncRNA as a potential therapeutic target in infectious diseases and inflammatory diseases.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação da Expressão Gênica , RNA Longo não Codificante/genética , Fator de Transcrição RelA/metabolismo , Transcrição Gênica , Fator de Necrose Tumoral alfa/genética , Animais , Linhagem Celular , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Citocinas/genética , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transcrição Gênica/genética
14.
Brain Behav Immun ; 106: 262-269, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36058419

RESUMO

Immune-brain interactions influence the pathophysiology of addiction. Lipopolysaccharide (LPS)-induced systemic inflammation produces effects on reward-related brain regions and the dopamine system. We previously showed that LPS amplifies dopamine elevation induced by methylphenidate (MP), compared to placebo (PBO), in eight healthy controls. However, the effects of LPS on the dopamine system of tobacco smokers have not been explored. The goal of Study 1 was to replicate previous findings in an independent cohort of tobacco smokers. The goal of Study 2 was to combine tobacco smokers with the aforementioned eight healthy controls to examine the effect of LPS on dopamine elevation in a heterogenous sample for power and effect size determination. Eight smokers were each scanned with [11C]raclopride positron emission tomography three times-at baseline, after administration of LPS (0.8 ng/kg, intravenously) and MP (40 mg, orally), and after administration of PBO and MP, in a double-blind, randomized order. Dopamine elevation was quantified as change in [11C]raclopride binding potential (ΔBPND) from baseline. A repeated-measures ANOVA was conducted to compare LPS and PBO conditions. Smokers and healthy controls were well-matched for demographics, drug dosing, and scanning parameters. In Study 1, MP-induced striatal dopamine elevation was significantly higher following LPS than PBO (p = 0.025, 18 ± 2.9 % vs 13 ± 2.7 %) for smokers. In Study 2, MP-induced striatal dopamine elevation was also significantly higher under LPS than under PBO (p < 0.001, 18 ± 1.6 % vs 11 ± 1.5 %) in the combined sample. Smoking status did not interact with the effect of condition. This is the first study to translate the phenomenon of amplified dopamine elevation after experimental activation of the immune system to an addicted sample which may have implications for drug reinforcement, seeking, and treatment.


Assuntos
Estimulantes do Sistema Nervoso Central , Metilfenidato , Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Dopamina/metabolismo , Humanos , Inflamação/metabolismo , Lipopolissacarídeos/metabolismo , Metilfenidato/farmacologia , Tomografia por Emissão de Pósitrons , Racloprida/metabolismo , Racloprida/farmacologia , Fumantes
15.
Nicotine Tob Res ; 24(10): 1597-1606, 2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-35100429

RESUMO

INTRODUCTION: Tobacco smoking is a major public health burden. The first-line pharmacological treatment for tobacco smoking is nicotine replacement therapy (eg, the nicotine patch (NIC)). Nicotine acts on nicotinic-acetylcholine receptors on dopamine terminals to release dopamine in the ventral and dorsal striatum encoding reward and habit formation, respectively. AIMS AND METHODS: To better understand treatment efficacy, a naturalistic experimental design combined with a kinetic model designed to characterize smoking-induced dopamine release in vivo was used. Thirty-five tobacco smokers (16 female) wore a NIC (21 mg, daily) for 1-week and a placebo patch (PBO) for 1-week in a randomized, counter-balanced order. Following 1-week under NIC and then overnight abstinence, smokers participated in a 90-minute [11C]raclopride positron emission tomography scan and smoked a cigarette while in the scanner. Identical procedures were followed for the PBO scan. A time-varying kinetic model was used at the voxel level to model transient dopamine release peaking instantaneously at the start of the stimulus and decaying exponentially. Magnitude and spatial extent of dopamine release were estimated. Smokers were subcategorized by nicotine dependence level and nicotine metabolism rate. RESULTS: Dopamine release magnitude was enhanced by NIC in ventral striatum and diminished by NIC in dorsal striatum. More-dependent smokers activated more voxels than the less-dependent smokers under both conditions. Under PBO, fast metabolizers activated more voxels in ventral striatum and fewer voxels in dorsal striatum compared to slow metabolizers. CONCLUSIONS: These findings demonstrate that the model captured a pattern of transient dopamine responses to cigarette smoking which may be different across smoker subgroup categorizations. IMPLICATIONS: This is the first study to show that NIC alters highly localized patterns of cigarette smoking-induced dopamine release and that levels of nicotine dependence and nicotine clearance rate contribute to these alterations. This current work included a homogeneous subject sample with regards to demographic and smoking variables, as well as a highly sensitive model capable of detecting significant acute dopamine transients. The findings of this study add support to the recent identification of biomarkers for predicting the effect of nicotine replacement therapies on dopamine function which could help refine clinical practice for smoking cessation.


Assuntos
Fumar Cigarros , Receptores Nicotínicos , Abandono do Hábito de Fumar , Tabagismo , Feminino , Humanos , Biomarcadores , Dopamina/metabolismo , Nicotina , Racloprida , Nicotiana/metabolismo , Dispositivos para o Abandono do Uso de Tabaco
16.
Sensors (Basel) ; 22(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080977

RESUMO

A human can infer the magnitude of interaction force solely based on visual information because of prior knowledge in human-robot interaction (HRI). A method of reconstructing tactile information through cross-modal signal processing is proposed in this paper. In our method, visual information is added as an auxiliary source to tactile information. In this case, the receiver is only able to determine the tactile interaction force from the visual information provided. In our method, we first process groups of pictures (GOPs) and treat them as the input. Secondly, we use the low-rank foreground-based attention mechanism (LAM) to detect regions of interest (ROIs). Finally, we propose a linear regression convolutional neural network (LRCNN) to infer contact force in video frames. The experimental results show that our cross-modal reconstruction is indeed feasible. Furthermore, compared to other work, our method is able to reduce the complexity of the network and improve the material identification accuracy.


Assuntos
Robótica , Percepção do Tato , Humanos , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador , Tato
17.
Alzheimers Dement ; 18(12): 2527-2536, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35174954

RESUMO

INTRODUCTION: For 30 years synapse loss has been referred to as the major pathological correlate of cognitive impairment in Alzheimer's disease (AD). However, this statement is based on remarkably few patients studied by autopsy or biopsy. With the recent advent of synaptic vesicle glycoprotein 2A (SV2A) positron emission tomography (PET) imaging, we have begun to evaluate the consequences of synaptic alterations in vivo. METHODS: We examined the relationship between synaptic density measured by [11 C]UCB-J PET and neuropsychological test performance in 45 participants with early AD. RESULTS: Global synaptic density showed a significant positive association with global cognition and performance on five individual cognitive domains in participants with early AD. Synaptic density was a stronger predictor of cognitive performance than gray matter volume. CONCLUSION: These results confirm neuropathologic studies demonstrating a significant association between synaptic density and cognitive performance, and suggest that this correlation extends to the early stages of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Tomografia por Emissão de Pósitrons/métodos , Sinapses/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Cognição , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
18.
Neuroimage ; 238: 118248, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34119639

RESUMO

PURPOSE: 11C-UCB-J PET imaging, targeting synaptic vesicle glycoprotein 2A (SV2A), has been shown to be a useful indicator of synaptic density in Alzheimer's disease (AD). For SV2A imaging, a decrease in apparent tracer uptake is often due to the combination of gray-matter (GM) atrophy and SV2A decrease in the remaining tissue. Our aim is to reveal the true SV2A change by performing partial volume correction (PVC). METHODS: We performed two PVC algorithms, Müller-Gärtner (MG) and 'iterative Yang' (IY), on 17 AD participants and 11 cognitive normal (CN) participants using the brain-dedicated HRRT scanner. Distribution volume VT, the rate constant K1, binding potential BPND (centrum semiovale as reference region), and tissue volume were compared. RESULTS: In most regions, both PVC algorithms reduced the between-group differences. Alternatively, in hippocampus, IY increased the significance of between-group differences while MG reduced it (VT, BPND and K1 group differences: uncorrected: 20%, 27%, 17%; MG: 18%, 22%, 14%; IY: 22%, 28%, 17%). The group difference in hippocampal volume (10%) was substantially smaller than any PET measures. MG increased GM binding values to a greater extent than IY due to differences in algorithm assumptions. CONCLUSION: 11C-UCB-J binding is significantly reduced in AD hippocampus, but PVC is important to adjust for significant volume reduction. After correction, PET measures are substantially more sensitive to group differences than volumetric MRI measures. Assumptions of each PVC algorithm are important and should be carefully examined and validated. For 11C-UCB-J, the less stringent assumptions of IY support its use as a PVC algorithm over MG.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Circulação Cerebrovascular/fisiologia , Humanos , Compostos Radiofarmacêuticos
19.
Gastrointest Endosc ; 93(2): 422-432.e3, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32598959

RESUMO

BACKGROUND AND AIMS: Rupture of gastroesophageal varices is the most common fatal adverse event of cirrhosis. EGD is considered the criterion standard for diagnosis and risk stratification of gastroesophageal variceal bleeding. The aim of this study was to train and validate a real-time deep convolutional neural network (DCNN) system, named ENDOANGEL, for diagnosing gastroesophageal varices and predicting the risk of rupture. METHODS: After training with 8566 images of endoscopic gastroesophageal varices from 3021 patients and 6152 images of normal esophagus/stomach from 3168 patients, ENDOANGEL was also tested with independent images and videos. It was also compared with endoscopists in several aspects. RESULTS: ENDOANGEL, in contrast with endoscopists, displayed higher accuracy of 97.00% and 92.00% in terms of detecting esophageal varices (EVs) and gastric varices (GVs) in an image contest (97.00% vs 93.94% , P < .01; 92.00% vs 84.43%, P < .05). It also surpassed endoscopists for red color signs of EVs and red spots of GVs (84.21% vs 73.45%, P < .01; 85.26% vs 77.52%, P < .05). Moreover, ENDOANGEL achieved comparable performance in the determination of size, form, color, and bleeding signs. ENDOANGEL also had good performance in making treatment suggestions. With regard to predicting risk factors in multicenter videos, ENDOANGEL showed great stability. CONCLUSIONS: Our data suggest that DCNNs were precise in detecting both EVs and GVs and performed excellently in uncovering the endoscopic risk factors of gastroesophageal variceal bleeding. Thus, the application of DCNNs will assist endoscopists in evaluating gastroesophageal varices more objectively and precisely. (Clinical trial registration number: ChiCTR1900023970.).


Assuntos
Varizes Esofágicas e Gástricas , Varizes , Endoscopia do Sistema Digestório , Varizes Esofágicas e Gástricas/diagnóstico , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Humanos , Cirrose Hepática/complicações , Redes Neurais de Computação , Estudos Retrospectivos
20.
Dig Dis Sci ; 66(10): 3578-3587, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33180244

RESUMO

BACKGROUND: Early detection is critical in limiting the spread of 2019 novel coronavirus (COVID-19). Although previous data revealed characteristics of GI symptoms in COVID-19, for patients with only GI symptoms onset, their diagnostic process and potential transmission risk are still unclear. METHODS: We retrospectively reviewed 205 COVID-19 cases from January 16 to March 30, 2020, in Renmin Hospital of Wuhan University. All patients were confirmed by virus nuclei acid tests. The clinical features and laboratory and chest tomographic (CT) data were recorded and analyzed. RESULTS: A total of 171 patients with classic symptoms (group A) and 34 patients with only GI symptoms (group B) were included. In patients with classical COVID-19 symptoms, GI symptoms occurred more frequently in severe cases compared to non-severe cases (20/43 vs. 91/128, respectively, p < 0.05). In group B, 91.2% (31/34) patients were non-severe, while 73.5% (25/34) patients had obvious infiltrates in their first CT scans. Compared to group A, group B patients had a prolonged time to clinic services (5.0 days vs. 2.6 days, p < 0.01) and a longer time to a positive viral swab normalized to the time of admission (6.9 days vs. 3.3 days, respectively, p < 0.01). Two patients in group B had family clusters of SARS-CoV-2 infection. CONCLUSION: Patients with only GI symptoms of COVID-19 may take a longer time to present to healthcare services and receive a confirmed diagnosis. In areas where infection is rampant, physicians must remain vigilant of patients presenting with acute gastrointestinal symptoms and should do appropriate personal protective equipment.


Assuntos
COVID-19/epidemiologia , Gastroenteropatias/epidemiologia , Adulto , Idoso , COVID-19/diagnóstico , COVID-19/virologia , China/epidemiologia , Feminino , Gastroenteropatias/diagnóstico , Gastroenteropatias/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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