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1.
Front Neurosci ; 18: 1455129, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145298

RESUMO

Background: The Montreal Cognitive Assessment (MoCA) is a valuable tool for detecting cognitive impairment, widely used in many countries. However, there is still a lack of large sample normative data and whose cut-off values for detecting cognitive impairment is considerable controversy. Methods: The assessment conducted in this study utilizes the MoCA scale, specifically employing the Mandarin-8.1 version. This study recruited a total of 3,097 healthy adults aged over 20 years. We performed multiple linear regression analysis, incorporating age, gender, and education level as predictor variables, to examine their associations with the MoCA total score and subdomain scores. Subsequently, we established normative values stratified by age and education level. Finally, we included 242 patients with vascular cognitive impairment (VCI) and 137 controls with normal cognition, and determined the optimal cut-off value of VCI through ROC curves. Results: The participants in this study exhibit a balanced gender distribution, with an average age of 54.46 years (SD = 14.38) and an average education period of 9.49 years (SD = 4.61). The study population demonstrates an average MoCA score of 23.25 points (SD = 4.82). The multiple linear regression analysis indicates that MoCA total score is influenced by age and education level, collectively accounting for 46.8% of the total variance. Higher age and lower education level are correlated with lower MoCA total scores. A score of 22 is the optimal cut-off value for diagnosing vascular cognitive impairment (VCI). Conclusion: This study offered normative MoCA values specific to the Chinese adults. Furthermore, this study indicated that a score of 26 may not represent the most optimal cut-off value for VCI. And for detecting VCI, a score of 22 may be a better cut-off value.

2.
Mol Cell ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39047724

RESUMO

RNA-RNA interactions (RRIs) can dictate RNA molecules to form intricate higher-order structures and bind their RNA substrates in diverse biological processes. To elucidate the function, binding specificity, and regulatory mechanisms of various RNA molecules, especially the vast repertoire of non-coding RNAs, advanced technologies and methods that globally map RRIs are extremely valuable. In the past decades, many state-of-the-art technologies have been developed for this purpose. This review focuses on those high-throughput technologies for the global mapping of RRIs. We summarize the key concepts and the pros and cons of different technologies. In addition, we highlight the novel biological insights uncovered by these RRI mapping methods and discuss the future challenges for appreciating the crucial roles of RRIs in gene regulation across bacteria, viruses, archaea, and mammals.

3.
Nat Commun ; 15(1): 5985, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013850

RESUMO

The mechanism by which aging induces aortic aneurysm and dissection (AAD) remains unclear. A total of 430 participants were recruited for the screening of differentially expressed plasma microRNAs (miRNAs). We found that miR-1204 is significantly increased in both the plasma and aorta of elder patients with AAD and is positively correlated with age. Cell senescence induces the expression of miR-1204 through p53 interaction with plasmacytoma variant translocation 1, and miR-1204 induces vascular smooth muscle cell (VSMC) senescence to form a positive feedback loop. Furthermore, miR-1204 aggravates angiotensin II-induced AAD formation, and inhibition of miR-1204 attenuates ß-aminopropionitrile monofumarate-induced AAD development in mice. Mechanistically, miR-1204 directly targets myosin light chain kinase (MYLK), leading to the acquisition of a senescence-associated secretory phenotype (SASP) by VSMCs and loss of their contractile phenotype. MYLK overexpression reverses miR-1204-induced VSMC senescence, SASP and contractile phenotypic changes, and the decrease of transforming growth factor-ß signaling pathway. Our findings suggest that aging aggravates AAD via the miR-1204-MYLK signaling axis.


Assuntos
Envelhecimento , Aneurisma Aórtico , Dissecção Aórtica , Senescência Celular , MicroRNAs , Músculo Liso Vascular , Quinase de Cadeia Leve de Miosina , Transdução de Sinais , Animais , Feminino , Humanos , Masculino , Camundongos , Envelhecimento/genética , Envelhecimento/metabolismo , Angiotensina II/metabolismo , Aneurisma Aórtico/metabolismo , Aneurisma Aórtico/genética , Aneurisma Aórtico/patologia , Dissecção Aórtica/metabolismo , Dissecção Aórtica/genética , Dissecção Aórtica/patologia , Proteínas de Ligação ao Cálcio , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Fator de Crescimento Transformador beta/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética
4.
Biol Psychiatry ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942349

RESUMO

BACKGROUND: Striatal hyperdopaminergia is implicated in the pathoetiology of schizophrenia, but how this relates to dopaminergic midbrain activity is unclear. Neuromelanin (NM)-sensitive magnetic resonance imaging provides a marker of long-term dopamine function. We examined whether midbrain NM-sensitive magnetic resonance imaging contrast-to-noise ratio (NM-CNR) was higher in people with schizophrenia than in healthy control (HC) participants and whether this correlated with dopamine synthesis capacity. METHODS: One hundred fifty-four participants (schizophrenia group: n = 74, HC group: n = 80) underwent NM-sensitive magnetic resonance imaging of the substantia nigra and ventral tegmental area (SN-VTA). A subset of the schizophrenia group (n = 38) also received [18F]-DOPA positron emission tomography to measure dopamine synthesis capacity (Kicer) in the SN-VTA and striatum. RESULTS: SN-VTA NM-CNR was significantly higher in patients with schizophrenia than in HC participants (effect size = 0.38, p = .019). This effect was greatest for voxels in the medial and ventral SN-VTA. In patients, SN-VTA Kicer positively correlated with SN-VTA NM-CNR (r = 0.44, p = .005) and striatal Kicer (r = 0.71, p < .001). Voxelwise analysis demonstrated that SN-VTA NM-CNR was positively associated with striatal Kicer (r = 0.53, p = .005) and that this relationship seemed strongest between the ventral SN-VTA and associative striatum in schizophrenia. CONCLUSIONS: Our results suggest that NM levels are higher in patients with schizophrenia than in HC individuals, particularly in midbrain regions that project to parts of the striatum that receive innervation from the limbic and association cortices. The direct relationship between measures of NM and dopamine synthesis suggests that these aspects of schizophrenia pathophysiology are linked. Our findings highlight specific mesostriatal circuits as the loci of dopamine dysfunction in schizophrenia and thus as potential therapeutic targets.

5.
J Med Virol ; 96(6): e29712, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38808555

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV) has caused severe intestinal diseases in pigs. It originates from bat coronaviruses HKU2 and has a potential risk of cross-species transmission, raising concerns about its zoonotic potential. Viral entry-related host factors are critical determinants of susceptibility to cells, tissues, or species, and remain to be elucidated for SADS-CoV. Type II transmembrane serine proteases (TTSPs) family is involved in many coronavirus infections and has trypsin-like catalytic activity. Here we examine all 18 members of the TTSPs family through CRISPR-based activation of endogenous protein expression in cells, and find that, in addition to TMPRSS2 and TMPRSS4, TMPRSS13 significantly facilitates SADS-CoV infection. This is confirmed by ectopic expression of TMPRSS13, and specific to trypsin-dependent SADS-CoV. Infection with pseudovirus bearing SADS-CoV spike protein indicates that TMPRSS13 acts at the entry step and is sensitive to serine protease inhibitor Camostat. Moreover, both human and pig TMPRSS13 are able to enhance the cell-cell membrane fusion and cleavage of spike protein. Overall, we demonstrate that TMPRSS13 is another host serine protease promoting the membrane-fusion entry of SADS-CoV, which may expand its host tropism by using diverse TTSPs.


Assuntos
Proteínas de Membrana , Serina Endopeptidases , Internalização do Vírus , Animais , Serina Endopeptidases/metabolismo , Serina Endopeptidases/genética , Suínos , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Alphacoronavirus/genética , Alphacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/metabolismo , Gabexato/análogos & derivados , Gabexato/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Células HEK293 , Linhagem Celular , Chlorocebus aethiops , Doenças dos Suínos/virologia , Ésteres , Guanidinas
6.
Neurology ; 102(12): e209460, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38815233

RESUMO

BACKGROUND AND OBJECTIVES: Alzheimer disease (AD) copathologies of ß-amyloid and tau are common in the Lewy body diseases (LBD), dementia with Lewy bodies (DLB) and Parkinson disease (PD), and target distinct hippocampal subfields compared with Lewy pathology, including subiculum and CA1. We investigated the hypothesis that AD copathologies impact the pattern of hippocampal subregion volume loss and cognitive function in LBD. METHODS: This was a cross-sectional and longitudinal, single-center, observational cohort study. Participants underwent neuropsychological testing and 3T-MRI with hippocampal segmentation using FreeSurferV7. PiB-PET and flortaucipir-PET imaging of comorbid ß-amyloid (A) and tau (T) were acquired. The association of functional cognition, ß-amyloid, and tau loads with hippocampal subregion volume was assessed. The contribution of subregion volumes to the relationship of AD-related deposits on functional cognition was examined with mediation analysis. The effects of AD-related deposits on the rate of subregion atrophy were evaluated with mixed-effects models. RESULTS: Of 103 participants (mean age: 70.3 years; 37.3% female), 52 had LBD with impaired cognition (LBD-I), 26 had normal cognition (LBD-N), and 25 were A- healthy controls (HCs). Volumes of hippocampal subregions prone to AD copathologies, including subiculum (F = 6.9, p = 0.002), presubiculum (F = 7.3, p = 0.001), and parasubiculum (F = 5.9, p = 0.004), were reduced in LBD-I compared with LBD-N and HC. Volume was preserved in CA2/3, Lewy pathology susceptible subregions. In LBD-I, reduced CA1, subiculum, and presubiculum volumes were associated with greater functional cognitive impairment (all p < 0.05). Compared with HC, subiculum volume was reduced in A+T+ but not A-T- participants (F = 2.62, p = 0.043). Reduced subiculum volume mediated the effect of amyloid on functional cognition (0.12, 95% CI: 0.005 to 0.26, p = 0.040). In 26 longitudinally-evaluated participants, baseline tau deposition was associated with faster CA1 (p = 0.021) and subiculum (p = 0.002) atrophy. DISCUSSION: In LBD, volume loss in hippocampal output subregions-particularly the subiculum-is associated with functional cognition and AD-related deposits. Tau deposition appears to accelerate subiculum and CA1 atrophy, whereas Aß does not. Subiculum volume may have value as a biomarker of AD copathology-mediated neurodegeneration and disease progression.


Assuntos
Peptídeos beta-Amiloides , Hipocampo , Doença por Corpos de Lewy , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/patologia , Feminino , Masculino , Idoso , Proteínas tau/metabolismo , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/metabolismo , Estudos Transversais , Peptídeos beta-Amiloides/metabolismo , Estudos Longitudinais , Imageamento por Ressonância Magnética , Idoso de 80 Anos ou mais , Testes Neuropsicológicos , Estudos de Coortes , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Pessoa de Meia-Idade
7.
Plants (Basel) ; 13(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38794447

RESUMO

In response to the challenge of low recognition rates for similar phenotypic symptoms of tea diseases in low-light environments and the difficulty in detecting small lesions, a novel adaptive method for tea disease severity detection is proposed. This method integrates an image enhancement algorithm based on an improved EnlightenGAN network and an enhanced version of YOLO v8. The approach involves first enhancing the EnlightenGAN network through non-paired training on low-light-intensity images of various tea diseases, guiding the generation of high-quality disease images. This step aims to expand the dataset and improve lesion characteristics and texture details in low-light conditions. Subsequently, the YOLO v8 network incorporates ResNet50 as its backbone, integrating channel and spatial attention modules to extract key features from disease feature maps effectively. The introduction of adaptive spatial feature fusion in the Neck part of the YOLOv8 module further enhances detection accuracy, particularly for small disease targets in complex backgrounds. Additionally, the model architecture is optimized by replacing traditional Conv blocks with ODConv blocks and introducing a new ODC2f block to reduce parameters, improve performance, and switch the loss function from CIOU to EIOU for a faster and more accurate recognition of small targets. Experimental results demonstrate that YOLOv8-ASFF achieves a tea disease detection accuracy of 87.47% and a mean average precision (mAP) of 95.26%. These results show a 2.47 percentage point improvement over YOLOv8, and a significant lead of 9.11, 9.55, and 7.08 percentage points over CornerNet, SSD, YOLOv5, and other models, respectively. The ability to swiftly and accurately detect tea diseases can offer robust theoretical support for assessing tea disease severity and managing tea growth. Moreover, its compatibility with edge computing devices and practical application in agriculture further enhance its value.

8.
Sensors (Basel) ; 24(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38733002

RESUMO

In order to efficiently identify early tea diseases, an improved YOLOv8 lesion detection method is proposed to address the challenges posed by the complex background of tea diseases, difficulty in detecting small lesions, and low recognition rate of similar phenotypic symptoms. This method focuses on detecting tea leaf blight, tea white spot, tea sooty leaf disease, and tea ring spot as the research objects. This paper presents an enhancement to the YOLOv8 network framework by introducing the Receptive Field Concentration-Based Attention Module (RFCBAM) into the backbone network to replace C2f, thereby improving feature extraction capabilities. Additionally, a mixed pooling module (Mixed Pooling SPPF, MixSPPF) is proposed to enhance information blending between features at different levels. In the neck network, the RepGFPN module replaces the C2f module to further enhance feature extraction. The Dynamic Head module is embedded in the detection head part, applying multiple attention mechanisms to improve multi-scale spatial location and multi-task perception capabilities. The inner-IoU loss function is used to replace the original CIoU, improving learning ability for small lesion samples. Furthermore, the AKConv block replaces the traditional convolution Conv block to allow for the arbitrary sampling of targets of various sizes, reducing model parameters and enhancing disease detection. the experimental results using a self-built dataset demonstrate that the enhanced YOLOv8-RMDA exhibits superior detection capabilities in detecting small target disease areas, achieving an average accuracy of 93.04% in identifying early tea lesions. When compared to Faster R-CNN, MobileNetV2, and SSD, the average precision rates of YOLOv5, YOLOv7, and YOLOv8 have shown improvements of 20.41%, 17.92%, 12.18%, 12.18%, 10.85%, 7.32%, and 5.97%, respectively. Additionally, the recall rate (R) has increased by 15.25% compared to the lowest-performing Faster R-CNN model and by 8.15% compared to the top-performing YOLOv8 model. With an FPS of 132, YOLOv8-RMDA meets the requirements for real-time detection, enabling the swift and accurate identification of early tea diseases. This advancement presents a valuable approach for enhancing the ecological tea industry in Yunnan, ensuring its healthy development.


Assuntos
Redes Neurais de Computação , Doenças das Plantas , Chá , Doenças das Plantas/microbiologia , Algoritmos , Camellia sinensis , Folhas de Planta/química
9.
BMC Public Health ; 24(1): 1307, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745217

RESUMO

BACKGROUND: In Guangdong Province, China, there is lack of information on the HIV epidemic among high-risk groups and the general population, particularly in relation to sexual transmission, which is a predominant route. The new HIV infections each year is also uncertain owing to HIV transmission from men who have sex with men (MSM) to women, as a substantial proportion of MSM also have female sexual partnerships to comply with social demands in China. METHODS: A deterministic compartmental model was developed to predict new HIV infections in four risk groups, including heterosexual men and women and low- and high-risk MSM, in Guangdong Province from 2016 to 2050, considering HIV transmission from MSM to women. The new HIV infections and its 95% credible interval (CrI) were predicted. An adaptive sequential Monte Carlo method for approximate Bayesian computation (ABC-SMC) was used to estimate the unknown parameter, a mixing index. We calibrated our results based on new HIV diagnoses and proportions of late diagnoses. The Morris and Sobol methods were applied in the sensitivity analysis. RESULTS: New HIV infections increased during and 2 years after the COVID-19 pandemic, then declined until 2050. New infections rose from 8,828 [95% credible interval (CrI): 6,435-10,451] in 2016 to 9,652 (95% CrI: 7,027-11,434) in 2019, peaking at 11,152 (95% CrI: 8,337-13,062) in 2024 before declining to 7,084 (95% CrI: 5,165-8,385) in 2035 and 4,849 (95% CrI: 3,524-5,747) in 2050. Women accounted for approximately 25.0% of new HIV infections, MSM accounted for 40.0% (approximately 55.0% of men), and high-risk MSM accounted for approximately 25.0% of the total. The ABC-SMC mixing index was 0.504 (95% CrI: 0.239-0.894). CONCLUSIONS: Given that new HIV infections and the proportion of women were relatively high in our calibrated model, to some extent, the HIV epidemic in Guangdong Province remains serious, and services for HIV prevention and control are urgently needed to return to the levels before the COVID-19 epidemic, especially in promoting condom-based safe sex and increasing awareness of HIV prevention to general population.


Assuntos
COVID-19 , Infecções por HIV , Humanos , China/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/prevenção & controle , Masculino , Feminino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Teorema de Bayes , Homossexualidade Masculina/estatística & dados numéricos , Adulto , Modelos Estatísticos
10.
Waste Manag ; 179: 1-11, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38442433

RESUMO

The application of in-situ aeration technology in landfills has been reported to promote fungal growth, but the community diversity and function of fungi in the aerated landfill system remain unknown. This study firstly investigated an in-situ aerated remediation landfill site to characterize the fungal community diversity in refuse. And to further reveal the fungal involvement in the nitrogen cycling system, laboratory-scale simulated aerated landfill reactors were then constructed. The results in the aerated landfill site showed a significant correlation between fungal community structure and ammonia nitrogen content in the refuse. Dominant fungi in the fungal community included commonly found environmental fungi such as Fusarium, Aspergillus, Gibberella, as well as unique fungi in the aerated system like Chaetomium. In the laboratory-scale aerated landfill simulation experiments, the fungal system was constructed using bacterial inhibitor, and nitrogen balance analysis confirmed the significant role of fungal nitrification in the nitrogen cycling process. When ammonia nitrogen was not readily available, fungi converted organic nitrogen to nitrate, serving as the main nitrification mechanism in the system, with a contribution rate ranging from 62.71 % to 100 % of total nitrification. However, when ammonia nitrogen was present in the system, autotrophic nitrification became the main mechanism, and the contribution of fungal nitrification to total nitrification was only 15.96 %. Additionally, fungi were capable of directly utilizing nitrite for nitrate production with a rate of 4.65 mg L-1 d-1. This research article contributes to the understanding of the importance of fungi in the aerated landfill systems, filling a gap in knowledge.


Assuntos
Micobioma , Poluentes Químicos da Água , Nitrogênio , Amônia , Nitratos , Nitrificação , Instalações de Eliminação de Resíduos , Reatores Biológicos , Desnitrificação
11.
Biol Psychiatry ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38521158

RESUMO

BACKGROUND: Electroconvulsive therapy (ECT) is an effective treatment for patients with major depressive disorder (MDD), but its underlying neural mechanisms remain largely unknown. The aim of this study was to identify changes in brain connectome dynamics after ECT in MDD and to explore their associations with treatment outcome. METHODS: We collected longitudinal resting-state functional magnetic resonance imaging data from 80 patients with MDD (50 with suicidal ideation [MDD-SI] and 30 without [MDD-NSI]) before and after ECT and 37 age- and sex-matched healthy control participants. A multilayer network model was used to assess modular switching over time in functional connectomes. Support vector regression was used to assess whether pre-ECT network dynamics could predict treatment response in terms of symptom severity. RESULTS: At baseline, patients with MDD had lower global modularity and higher modular variability in functional connectomes than control participants. Network modularity increased and network variability decreased after ECT in patients with MDD, predominantly in the default mode and somatomotor networks. Moreover, ECT was associated with decreased modular variability in the left dorsal anterior cingulate cortex of MDD-SI but not MDD-NSI patients, and pre-ECT modular variability significantly predicted symptom improvement in the MDD-SI group but not in the MDD-NSI group. CONCLUSIONS: We highlight ECT-induced changes in MDD brain network dynamics and their predictive value for treatment outcome, particularly in patients with SI. This study advances our understanding of the neural mechanisms of ECT from a dynamic brain network perspective and suggests potential prognostic biomarkers for predicting ECT efficacy in patients with MDD.

12.
Elife ; 122024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271475

RESUMO

Spermatogonial stem cells (SSCs) are essential for continuous spermatogenesis and male fertility. The underlying mechanisms of alternative splicing (AS) in mouse SSCs are still largely unclear. We demonstrated that SRSF1 is essential for gene expression and splicing in mouse SSCs. Crosslinking immunoprecipitation and sequencing data revealed that spermatogonia-related genes (e.g. Plzf, Id4, Setdb1, Stra8, Tial1/Tiar, Bcas2, Ddx5, Srsf10, Uhrf1, and Bud31) were bound by SRSF1 in the mouse testes. Specific deletion of Srsf1 in mouse germ cells impairs homing of precursor SSCs leading to male infertility. Whole-mount staining data showed the absence of germ cells in the testes of adult conditional knockout (cKO) mice, which indicates Sertoli cell-only syndrome in cKO mice. The expression of spermatogonia-related genes (e.g. Gfra1, Pou5f1, Plzf, Dnd1, Stra8, and Taf4b) was significantly reduced in the testes of cKO mice. Moreover, multiomics analysis suggests that SRSF1 may affect survival of spermatogonia by directly binding and regulating Tial1/Tiar expression through AS. In addition, immunoprecipitation mass spectrometry and co-immunoprecipitation data showed that SRSF1 interacts with RNA splicing-related proteins (e.g. SART1, RBM15, and SRSF10). Collectively, our data reveal the critical role of SRSF1 in spermatogonia survival, which may provide a framework to elucidate the molecular mechanisms of the posttranscriptional network underlying homing of precursor SSCs.


Assuntos
Espermatogônias , Testículo , Animais , Masculino , Camundongos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Processamento de RNA/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Espermatogênese/genética , Espermatogônias/metabolismo , Células-Tronco/metabolismo , Testículo/metabolismo
13.
Chem Sci ; 15(4): 1318-1323, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38274074

RESUMO

As an important class of multicomponent reactions, the palladium/norbornene (Pd/NBE) cooperative catalysis has been mainly restricted to the coupling of an aryl halide, an electrophile and a nucleophile. Here, we report the development of a Pd/NBE-catalyzed four-component reaction, which involves ortho C-H amination/ipso conjunctive coupling using an alkene and an external nucleophile. The use of alkene-tethered nitrogen electrophiles provides a rapid and modular synthesis of 3,3-disubstituted indolines from readily available aryl iodides. The reaction exhibits broad functional group tolerance, and its utility is exemplified in a streamlined formal synthesis of a rhodamine dye. Preliminary results of the asymmetric version of this reaction have also been obtained.

14.
Prog Neurobiol ; 233: 102568, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216113

RESUMO

The Topoisomerase 3B (Top3b) - Tudor domain containing 3 (Tdrd3) protein complex is the only dual-activity topoisomerase complex that can alter both DNA and RNA topology in animals. TOP3B mutations in humans are associated with schizophrenia, autism and cognitive disorders; and Top3b-null mice exhibit several phenotypes observed in animal models of psychiatric and cognitive disorders, including impaired cognitive and emotional behaviors, aberrant neurogenesis and synaptic plasticity, and transcriptional defects. Similarly, human TDRD3 genomic variants have been associated with schizophrenia, verbal short-term memory and educational attainment. However, the importance of Tdrd3 in normal brain function has not been examined in animal models. Here we generated a Tdrd3-null mouse strain and demonstrate that these mice display both shared and unique defects when compared to Top3b-null mice. Shared defects were observed in cognitive behaviors, synaptic plasticity, adult neurogenesis, newborn neuron morphology, and neuronal activity-dependent transcription; whereas defects unique to Tdrd3-deficient mice include hyperactivity, changes in anxiety-like behaviors, olfaction, increased new neuron complexity, and reduced myelination. Interestingly, multiple genes critical for neurodevelopment and cognitive function exhibit reduced levels in mature but not nascent transcripts. We infer that the entire Top3b-Tdrd3 complex is essential for normal brain function, and that defective post-transcriptional regulation could contribute to cognitive and psychiatric disorders.


Assuntos
Disfunção Cognitiva , Regulação da Expressão Gênica , Animais , Humanos , Camundongos , Sequência de Aminoácidos , Neurogênese/genética , Plasticidade Neuronal/genética , Proteínas/genética , Proteínas/metabolismo
15.
ACS Cent Sci ; 10(1): 65-76, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38292618

RESUMO

Quantifying adsorption behaviors is crucial for various applications such as catalysis, separation, and sensing, yet it is generally challenging to access in solution. Here, we report a combined experimental and computational study of the adsorption behaviors of alkyl-trimethylammonium bromides (xTAB), a class of ligands important for colloidal nanoparticle stabilization and shape control, with various alkyl chain lengths x on Au nanoparticles. We use density functional theory (DFT) to calculate xTAB binding energies on Au{111} and Au{110} surfaces with standing-up and lying-down configurations, which provides insights into the adsorption affinity and cooperativity differences of xTAB on these two facets. We demonstrate the key role of van der Waals interactions in determining the xTAB adsorption behavior. These computational results predict and explain the experimental discovery of xTAB's adsorption behavior switch from stronger affinity, negative cooperativity to weaker affinity, positive cooperativity when the concentration of xTAB increases in solution. We also show that in the standing-up configuration, bilayer adsorption may occur on both facets, which can lead to different differential binding energies and consequently adsorption crossover between the two facets when the ligand concentration increases. Our combined experimental and computational approaches demonstrate a paradigm for gaining molecular-scale insights into adsorbate-surface interactions.

16.
Neuroendocrinology ; 114(2): 158-169, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37703840

RESUMO

INTRODUCTION: To investigate the impact of prognostic nutritional index (PNI) on short- and long-term outcomes of patients who underwent curative-intent resection for gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs). METHODS: Patients with GET-NETs who underwent curative-intent resection were identified from a multi-center database. The prognostic impact of clinicopathological factors including PNI on post-operative outcomes were evaluated. A novel nomogram was developed and externally validated. RESULTS: A total of 2,099 patients with GEP-NETs were included in the training cohort; 255 patients were in the external validation cohort. Median PNI (n = 973) was 47.4 (IQR 43.1-52.4). At the time of presentation, 1,299 (61.9%) patients presented with some type of clinical symptom. Low-PNI (≤42.2) was associated with gastrointestinal symptoms, as well as nodal metastasis and distant metastasis (all p < 0.05). Patients with a low PNI had a higher incidence of severe (≥Clavien-Dindo grade IIIa: low PNI 24.9% vs. high PNI 15.4%, p = 0.001) and multiple (≥3 types of complications: low PNI 14.5% vs. high PNI 9.2%, p = 0.024) complications, as well as a worse overall survival (OS)(5-year OS, low PNI 73.7% vs. high PNI 88.5%, p < 0.001), and RFS (5-year RFS, low PNI 68.5% vs. high PNI 79.8%, p = 0.008) versus patients with high PNI (>42.2). A nomogram based on PNI, tumor grade and metastatic disease demonstrated excellent discrimination and calibration to predict OS in both the training (C-index 0.748) and two external validation (C-index 0.827, 0.745) cohorts. CONCLUSIONS: Low PNI was common and associated with worse short- and long-term outcomes among patients with GEP-NETs.


Assuntos
Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Avaliação Nutricional , Prognóstico , Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos
17.
Anticancer Drugs ; 35(1): 55-62, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823256

RESUMO

Sorafenib has been approved for advance hepatocellular carcinoma (HCC), however, drug resistance often occurred. Therefore, it is of great significance to clarify the underlying mechanisms of sorafenib resistance and to find out the effective strategies to overcome sorafenib resistance. The expression of HCG18 was detected by qPCR, MTT, colony formation, flow cytometry and TUNEL assay were used to explore the function of HCG18 on sorafenib resistance in HCC. RNA pull-down, RNA immunoprecipitation, immunofluorescence labeling, luciferase reporter assay, western blot and qPCR were used to investigate the mechanism of HCG18 regulating sorafenib resistance in HCC. Our results showed that HCG18 was significantly increased in HCC, which resulted in shorter 5-year survival for patients with HCC. Sorafenib can induce the expression of HCG18, suggesting HCG18 might be involved in sorafenib resistance in HCC. Further analysis showed that knockdown of HCG18 can reduce viability and increase apoptosis of HCC cells. Mechanistically, HCG18 can bind to USP15, further regulated the protein stability of p65, TAB2 and TAB3, and nuclear location of p65, which finally modulated the NF-κB signaling. Our findings showed that HCG18 played an important role in sorafenib resistance in HCC. And knockdown of HCG18 can promote the sensitivity of HCC cells to sorafenib, inferring that targeting HCG18 might be an effective strategy to overcome sorafenib resistance in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Sorafenibe/farmacologia , Neoplasias Hepáticas/genética , Resistencia a Medicamentos Antineoplásicos , RNA/farmacologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Proteases Específicas de Ubiquitina/farmacologia
18.
Nat Chem ; 16(2): 210-217, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37945834

RESUMO

Microscopic sequences of synthetic polymers play crucial roles in the polymer properties, but are generally unknown and inaccessible to traditional measurements. Here we report real-time optical sequencing of single synthetic copolymer chains under living polymerization conditions. We achieve this by carrying out multi-colour imaging of polymer growth by single catalysts at single-monomer resolution using CREATS (coupled reaction approach toward super-resolution imaging). CREATS makes a reaction effectively fluorogenic, enabling single-molecule localization microscopy of chemical reactions at higher reactant concentrations. Our data demonstrate that the chain propagation kinetics of surface-grafted polymerization contains temporal fluctuations with a defined memory time (which can be attributed to neighbouring monomer interactions) and chain-length dependence (due to surface electrostatic effects). Furthermore, the microscopic sequences of individual copolymers reveal their tendency to form block copolymers, and, more importantly, quantify the size distribution of individual blocks for comparison with theoretically random copolymers. Such sequencing capability paves the way for single-chain-level structure-function correlation studies of synthetic polymers.

19.
Int Wound J ; 21(4): e14527, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38095110

RESUMO

Thrombophlebitis is the inflammatory condition characterized by obstruction of one or more vessels, commonly in the legs, due to the formation of blood clots. It has been reported that traditional Chinese medicine, including Mailuoning injection, is advantageous for treating inflammatory and blood disorders. This research assessed the therapeutic efficacy of Mailuoning injection in the treatment of thrombophlebitis in rodents, as well as investigated its impact on fibrinolysis, inflammation, and coagulation. An experimental setup for thrombophlebitis was established in rodents via modified ligation technique. Five groups comprised the animals: sham operation group, model group, and three Mailuoning treatment groups (low, medium, and high dosages). The pain response, edema, coagulation parameters (PT, APTT, TT, FIB), serum inflammatory markers (IL-6, TNF-α, CRP), and expression levels of endothelial markers (ICAM-1, VCAM-1, NF-κB) were evaluated. Blood flow and vascular function were further assessed by measuring hemorheological parameters and the concentrations of TXB2, ET, and 6-k-PGF1α. In contrast to the sham group, model group demonstrated statistically significant increases in endothelial expression levels, coagulation latencies, and inflammatory markers (p < 0.05). The administration of mailing, specifically at high and medium dosages, resulted in a substantial reduction in inflammatory markers, enhancement of coagulation parameters, suppression of ICAM-1 and VCAM-1 expression, and restoration of hemorheological measurements to baseline (p < 0.05). Significantly higher concentrations of 6-k-PGF1α and lower levels of TXB2 and ET were observed in high-dose group, suggesting that pro- and anti-thrombotic factors were restored to equilibrium. Utilization of Mailuoning injection in rat model of thrombophlebitis exhibited significant therapeutic impact. This effect was manifested through pain alleviation, diminished inflammation, enhanced blood viscosity and facilitation of fibrinolysis. The study indicated that Mailuoning injection may serve as a viable therapeutic option for thrombophlebitis, potentially aiding in the improvement of wound healing by virtue of its anti-inflammatory and blood flow-enhancing characteristics.


Assuntos
Medicamentos de Ervas Chinesas , Molécula 1 de Adesão Intercelular , Tromboflebite , Ratos , Animais , Molécula 1 de Adesão Intercelular/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Cicatrização , Inflamação/tratamento farmacológico , Tromboflebite/tratamento farmacológico , Dor
20.
Mol Cell ; 84(3): 490-505.e9, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128540

RESUMO

SARS-CoV-2 RNA interacts with host factors to suppress interferon responses and simultaneously induces cytokine release to drive the development of severe coronavirus disease 2019 (COVID-19). However, how SARS-CoV-2 hijacks host RNAs to elicit such imbalanced immune responses remains elusive. Here, we analyzed SARS-CoV-2 RNA in situ structures and interactions in infected cells and patient lung samples using RIC-seq. We discovered that SARS-CoV-2 RNA forms 2,095 potential duplexes with the 3' UTRs of 205 host mRNAs to increase their stability by recruiting RNA-binding protein YBX3 in A549 cells. Disrupting the SARS-CoV-2-to-host RNA duplex or knocking down YBX3 decreased host mRNA stability and reduced viral replication. Among SARS-CoV-2-stabilized host targets, NFKBIZ was crucial for promoting cytokine production and reducing interferon responses, probably contributing to cytokine storm induction. Our study uncovers the crucial roles of RNA-RNA interactions in the immunopathogenesis of RNA viruses such as SARS-CoV-2 and provides valuable host targets for drug development.


Assuntos
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , RNA Viral/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Interferons/genética , Citocinas
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