Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 507
Filtrar
1.
J Acoust Soc Am ; 155(5): 3394-3409, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775634

RESUMO

In this paper, a series of impulse response functions between acoustic quantities on the source plane and particle velocity on the hologram plane are derived. In virtue of these functions, real-time nearfield acoustic holography (RT-NAH) is extended from pressure-based to particle velocity. Pressure, normal velocity, acceleration, and displacement radiated from planar sources can be reconstructed by measuring time-dependent particle velocity signals on the hologram plane. A simulation of an excited aluminum plate is performed to evaluate the difference in accuracy between RT-NAHs based on pressure and based on particle velocity. This study also examines the impact of impulse response functions on the reconstruction results, allowing for detailed analysis of the reconstruction accuracy based on these functions. The simulation results demonstrate that using RT-NAH based on particle velocity obtains significantly higher-accuracy reconstruction results when reconstructing normal velocity and displacement and slightly more accurate reconstructed pressure and normal acceleration.

2.
Parkinsonism Relat Disord ; 124: 106985, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38718478

RESUMO

BACKGROUND: Essential tremor (ET) and dystonic tremor (DT) are the two most common tremor disorders, and misdiagnoses are very common due to similar tremor symptoms. In this study, we explore the structural network mechanisms of ET and DT using brain grey matter (GM) morphological networks and combine those with machine learning models. METHODS: 3D-T1 structural images of 75 ET patients, 71 DT patients, and 79 healthy controls (HCs) were acquired. We used voxel-based morphometry to obtain GM images and constructed GM morphological networks based on the Kullback-Leibler divergence-based similarity (KLS) method. We used the GM volumes, morphological relations, and global topological properties of GM-KLS morphological networks as input features. We employed three classifiers to perform the classification tasks. Moreover, we conducted correlation analysis between discriminative features and clinical characteristics. RESULTS: 16 morphological relations features and 1 global topological metric were identified as the discriminative features, and mainly involved the cerebello-thalamo-cortical circuits and the basal ganglia area. The Random Forest (RF) classifier achieved the best classification performance in the three-classification task, achieving a mean accuracy (mACC) of 78.7%, and was subsequently used for binary classification tasks. Specifically, the RF classifier demonstrated strong classification performance in distinguishing ET vs. HCs, ET vs. DT, and DT vs. HCs, with mACCs of 83.0 %, 95.2 %, and 89.3 %, respectively. Correlation analysis demonstrated that four discriminative features were significantly associated with the clinical characteristics. CONCLUSION: This study offers new insights into the structural network mechanisms of ET and DT. It demonstrates the effectiveness of combining GM-KLS morphological networks with machine learning models in distinguishing between ET, DT, and HCs.

3.
Epilepsy Res ; 203: 107368, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38713974

RESUMO

BACKGROUND: Researchers have studied the risk factors for epilepsy recurrence among patients who withdraw from antiseizure medication (ASM). These studies aimed to determine the optimal time for ASM withdrawal. EEG findings are one of the risk factors that has been studied. However, it remains unclear whether abnormal pretreatment EEG findings are a risk factor for recurrence after ASM withdrawal. We performed this meta-analysis to clarify this issue. METHODS: We retrieved literature from the PubMed and Embase databases, and used the NewcastleOttawa Scale to evaluate the methodological quality of the included studies. RevMan 5.3 software was used to analyse the data. RESULTS: In total,710 articles were retrieved from the databases. Ultimately, after screening, 11 articles involving 1686 patients with epilepsy were included. Compared with that for a normal EEG, the odds ratio (OR) for an abnormal EEG was 1.10 (P=0.50), with an I2 value of 32% (P=0.15). Subgroup analysis revealed that the children-to-adolescents subgroup had an OR of 1.21 (P=0.27), and the children-to-adults subgroup had an OR of 0.64 (P=0.14) for an abnormal EEG. A separate subgroup analysis revealed that the focal epilepsy subgroup had an OR of 1.30 (P=0.37), and the generalized epilepsy and focal epilepsy subgroup had an OR of 1.07 (P=0.67) for an abnormal EEG. CONCLUSIONS: The risk of epilepsy recurrence is not related to pretreatment EEG findings, regardless of age or epilepsy classification. The associations of pre- and posttreatment EEG alterations with epilepsy recurrence are controversial. Due to the limitations of our article, further research is needed.

4.
iScience ; 27(6): 109867, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38784000

RESUMO

This study examines the relationship between gastrointestinal symptoms in patients with functional gastrointestinal disorders (FGIDs) and type D personality traits, as well as emotion regulation strategies. Analyzing a diverse group of FGID patients, we uncover significant effects of gender and age on gastrointestinal symptoms. Negative Affectivity emerges as a key predictor, positively associated with symptom severity, whereas Social Inhibition correlates negatively with Abdominal Pain. Additionally, our findings suggest that the expressive suppression strategy predicts heightened gastrointestinal symptoms, whereas cognitive reappraisal predicts lower levels of certain symptoms. These findings provide valuable insights for precise diagnosis and tailored treatments of FGIDs. Further research is warranted to explore underlying mechanisms and inform evidence-based interventions.

5.
Epilepsy Behav ; 154: 109748, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38640553

RESUMO

OBJECTIVE: Comorbid depression and anxiety in patients with epilepsy (PWE) are common and frequently under-treated, thus, causing poor health-related quality of life (HRQoL). However, little is known regarding the interconnections between anxious/depressive symptoms and the dimensions of HRQoL. Therefore, we conducted a network analysis to explore these relationships in detail among Chinese adult PWE. METHODS: A cohort of adult PWE was consecutively recruited from the First Affiliated Hospital of Chongqing Medical University. HRQoL, depression, and anxiety were measured with Quality of Life in Epilepsy Inventory-31, Neurological Disorders Depression Inventory for Epilepsy, and Generalized Anxiety Disorder 7-Item Scale, respectively. A regularized partial correlation network was constructed to investigate the interconnections between symptoms of anxiety/depression and the dimensions of HRQoL. We calculated expected influence (EI) and bridge expected influence (BEI) values to identify the most influential nodes. RESULTS: A total of 396 PWE were enrolled in this study, 78.1% of whom had focal onset epilepsy. The prevalence of anxiety and depression was 30.3% and 28.8%, respectively. The symptoms "frustrated" and "uncontrollable worry" had the highest EI values, whereas "emotional well-being", "seizure worry", "difficulty finding pleasure", and "nervousness or anxiety" had the highest BEI values. CONCLUSION: This study provides new insights into the relationships among anxiety, depression, and HRQoL. Critical central symptoms and bridge symptoms identified in the network might help to quickly identify PWE comorbid anxiety and depression in busy outpatient settings, thereby enabling early intervention and enhancing quality of life.


Assuntos
Ansiedade , Depressão , Epilepsia , Qualidade de Vida , Humanos , Qualidade de Vida/psicologia , Feminino , Masculino , Adulto , Epilepsia/psicologia , Epilepsia/epidemiologia , Epilepsia/complicações , Depressão/epidemiologia , Depressão/psicologia , Ansiedade/psicologia , Ansiedade/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem , Escalas de Graduação Psiquiátrica , Estudos de Coortes , Adolescente , Idoso , Comorbidade
6.
Neurol Sci ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528280

RESUMO

BACKGROUND: Essential tremor (ET) and Parkinson's disease (PD) are the two most prevalent movement disorders, sharing several overlapping tremor clinical features. Although growing evidence pointed out that changes in similar brain network nodes are associated with these two diseases, the brain network topological properties are still not very clear. OBJECTIVE: The combination of graph theory analysis with machine learning (ML) algorithms provides a promising way to reveal the topological pathogenesis in ET and tremor-dominant PD (tPD). METHODS: Topological metrics were extracted from Resting-state functional images of 86 ET patients, 86 tPD patients, and 86 age- and sex-matched healthy controls (HCs). Three steps were conducted to feature dimensionality reduction and four frequently used classifiers were adopted to discriminate ET, tPD, and HCs. RESULTS: A support vector machine classifier achieved the best classification performance of four classifiers for discriminating ET, tPD, and HCs with 89.0% mean accuracy (mACC) and was used for binary classification. Particularly, the binary classification performances among ET vs. tPD, ET vs. HCs, and tPD vs. HCs were with 94.2% mACC, 86.0% mACC, and 86.3% mACC, respectively. The most power discriminative features were mainly located in the default, frontal-parietal, cingulo-opercular, sensorimotor, and cerebellum networks. Correlation analysis results showed that 2 topological features negatively and 1 positively correlated with clinical characteristics. CONCLUSIONS: These results demonstrated that combining topological metrics with ML algorithms could not only achieve high classification accuracy for discrimination ET, tPD, and HCs but also help to reveal the potential brain topological network pathogenesis in ET and tPD.

7.
Front Plant Sci ; 15: 1362125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486855

RESUMO

The presence of burrowing mammals can have extensive effects on plants and soils, creating bare soil patches in alpine meadows and potentially altering plant-soil carbon (C) and nitrogen (N). This study focuses on the plateau pika (Ochotona curzoniae) to examine the responses of plant-soil C and N to a small burrowing mammal from quadrat scale to plot scale. The density of active burrow entrances in disturbed plots was used as an indicator of the disturbance intensity of plateau pikas. The study found that the below-ground biomass (BGB) and its C and N, as well as soil C and N concentrations were significantly lower in bare soil areas than in vegetated areas and undisturbed plots. This shows that the quadrat scale limited the estimation of the C and N sequestration potential. Therefore, further research on the plot scale found that the disturbance by plateau pika significantly reduced plant biomass and BGB carbon stock. However, plateau pika did not affect soil C and N stocks or ecosystem C and N stocks. These findings suggest the bare soil patches formed by plateau pika caused plant and soil heterogeneity but had a trade-off effect on plant-soil C and N stocks at the plot scale. Nevertheless, moderate disturbance intensity increased the C and N sequestration potential in grassland ecosystems. These results provide a possible way to estimate how disturbance by small burrowing mammals affects C and N cycling in grassland ecosystems while accurately assessing the effects of small burrowing mammal densities on C and N in grassland ecosystems.

8.
Int J Biol Sci ; 20(5): 1815-1832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481817

RESUMO

Chronic pressure overload can cause pathological cardiac remodeling and eventually heart failure. The ubiquitin specific protease (USP) family proteins play a prominent role in regulating substrate protein degradation and cardiac structural and functional homeostasis. Although USP38 is expressed in the heart, uncertainty exists regarding the function of USP38 in pathological cardiac remodeling. We constructed and generated cardiac specific USP38 knockout mice and cardiac specific USP38 overexpression mice to assess the role of USP38 in pathological cardiac remodeling. Furthermore, we used co-immunoprecipitation (Co-IP) assays and western blot analysis to identify the molecular interaction events. Here, we reported that the expression of USP38 is significantly elevated under a hypertrophic condition in vivo and in vitro. USP38 deletion significantly mitigates cardiomyocyte enlargement in vitro and hypertrophic effect induced by pressure overload, while overexpression of USP38 markedly aggravates cardiac hypertrophy and remodeling. Mechanistically, USP38 interacts with TANK-binding kinase 1 (TBK1) and removes K48-linked polyubiquitination of TBK1, stabilizing p-TBK1 and promoting the activation of its downstream mediators. Overexpression of TBK1 in the heart of cardiac specific USP38 knockout mice partially counteracts the benefit of USP38 deletion on pathological cardiac remodeling. The TBK1 inhibitor Amlexanox significantly alleviates pressure overload induced-cardiac hypertrophy and myocardial fibrosis in mice with USP38 overexpression. Our results demonstrate that USP38 serves as a positive regulator of pathological cardiac remodeling and suggest that targeting the USP38-TBK1 axis is a promising treatment strategy for hypertrophic heart failure.


Assuntos
Insuficiência Cardíaca , Transdução de Sinais , Animais , Camundongos , Cardiomegalia/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Remodelação Ventricular/genética
9.
Foods ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38472821

RESUMO

Freshly harvested Tremella fuciformis contains high water content with an unprotected outer surface and exhibits high respiration rates, which renders it prone to moisture and nutrient loss, leading to decay during storage. Our research utilized ε-poly-L-lysine (ε-PL) and chitosan as a composite coating preservative on fresh T. fuciformis. The findings revealed that the ε-PL + chitosan composite coating preservative effectively delayed the development of diseases and reduced weight loss during storage compared to the control group. Furthermore, this treatment significantly decreased the respiration rate of T. fuciformis and the activity of respiratory metabolism-related enzymes, such as alternative oxidase (AOX), cytochrome c oxidase (CCO), succinic dehydrogenase (SDH), 6-phosphogluconate dehydrogenase, and glucose-6-phosphate dehydrogenase (6-PGDH and G-6-PDH). Additionally, the composite coating preservative also delayed the depletion of ATP and ADP and maintained higher levels of the energy charge while preserving low levels of AMP. It also sustained heightened activities of Mg2+-ATPase, Ca2+-ATPase, and H+-ATPase enzymes. These results demonstrate that utilizing the ε-PL + chitosan composite coating preservative can serve as a sufficiently safe and efficient method for prolonging the shelf life of post-harvest fresh T. fuciformis.

11.
Brain Behav ; 14(3): e3463, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38451009

RESUMO

BACKGROUND: Despite numerous investigations into the relationship between physical activities (PA) and epilepsy, the causal effects remain contentious. Thus, we conducted a two-sample Mendelian randomization (MR) study to assess the potential causality. METHODS: Single-nucleotide polymorphisms (SNPs) predisposed to self-reported moderate and vigorous physical activities (MPA and VPA) and overall acceleration average (OAA) calculated through wrist-worn accelerometers were selected as exposure instrumental variables. Five subtypes of epilepsy, including all epilepsy, focal epilepsy and generalized epilepsy (with or without each other), focal epilepsy-strict definition and generalized epilepsy-strict definition (without overlap), were chosen as the outcomes. The MR study utilized the inverse-variance weighted (IVW) method as the primary analytical tool, supplemented by MR-Egger, simple mode, weighted mode, and weighted median methods. Cochran's Q and MR-Egger intercept tests were employed to assess heterogeneity and pleiotropy, while MR pleiotropy residual sum and outlier and leave-one-out analyses were conducted to identify potential SNP outliers. RESULTS: The study indicated that OAA was genetically linked to a decreased risk of both focal epilepsy (OR = 0.812, 95% CI: 0.687-0.960, p = .015, IVW) and focal epilepsy-strict definition (OR = 0.732, 95% CI: 0.596-0.900, p = .003, IVW; OR = 0.749, 95% CI: 0.573-0.979, p = .035, Weighted median). Genetically predicted MPA and VPA did not exhibit a causal association with all epilepsy or its subtypes (p>.05). No evidence of heterogeneity, pleiotropy, or SNP outlier was observed. CONCLUSIONS: Our findings suggested that PA with accelerometer monitoring may potentially reduce the risk of focal epilepsy, while there is no evidence supporting causal association between self-reported MPA or VPA and either focal or generalized epilepsy.


Assuntos
Epilepsias Parciais , Epilepsia Generalizada , Epilepsia , Humanos , Análise da Randomização Mendeliana , Epilepsia/genética , Exercício Físico
12.
Math Biosci Eng ; 21(1): 679-711, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303439

RESUMO

In recent years, with the development of science and technology, powerful computing devices have been constantly developing. As an important foundation, deep learning (DL) technology has achieved many successes in multiple fields. In addition, the success of deep learning also relies on the support of large-scale datasets, which can provide models with a variety of images. The rich information in these images can help the model learn more about various categories of images, thereby improving the classification performance and generalization ability of the model. However, in real application scenarios, it may be difficult for most tasks to collect a large number of images or enough images for model training, which also restricts the performance of the trained model to a certain extent. Therefore, how to use limited samples to train the model with high performance becomes key. In order to improve this problem, the few-shot learning (FSL) strategy is proposed, which aims to obtain a model with strong performance through a small amount of data. Therefore, FSL can play its advantages in some real scene tasks where a large number of training data cannot be obtained. In this review, we will mainly introduce the FSL methods for image classification based on DL, which are mainly divided into four categories: methods based on data enhancement, metric learning, meta-learning and adding other tasks. First, we introduce some classic and advanced FSL methods in the order of categories. Second, we introduce some datasets that are often used to test the performance of FSL methods and the performance of some classical and advanced FSL methods on two common datasets. Finally, we discuss the current challenges and future prospects in this field.

13.
Zhen Ci Yan Jiu ; 49(2): 135-144, 2024 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38413034

RESUMO

OBJECTIVES: To observe the effect of electroacupuncture (EA) of scalp acupoint (Dingnieqian-xiexian, MS6) on expression of retinoid-related orphan receptor γT (ROR γ t), interleukin (IL)-17A, IL-10, transfor-ming growth factor-ß1 (TGF-ß1), IL-6, IL-21, and IL-17A+ Thelper cells(Th) 17 and forkhead transcription factor P3 (FOXP3)+ regulatory T cells (Treg) differentiation of ischemic cortex in ischemic stroke rats, so as to explore its molecular mechanisms underlying relief of inflammatory injury of ischemic stroke. METHODS: A total of 120 male SD rats were randomly assigned to sham operation, model, EA, inhibitor, agonist and EA+agonist groups, with 15 rats in each group. The ischemic stroke model was established by occlusion of the left middle cerebral artery according to Longa's methods. For rats of the EA group and EA+agonist group, EA (2 Hz/100 Hz, 1 mA) was applied to bilateral MS6 for 30 min, once daily for 7 days. Rats of the inhibitor group received intraperitoneal injection of solution of SR1001 (RORγt inhibitor) (2.5 mg/mL, 10 mg/kg), once daily for 7 days. Rats of the agonist and EA+agonist groups received intraperitoneal injection of solution of SR1078 (RORγt agonist) (5 mg/mL, 5 mg/kg) before EA, once daily for 7 days. Rats of the sham operation and model groups were grabbed and fixed in the same way with the other groups. The Zea-longa's score, modified neurological severity score (mNSS) and the neurobehavioral score were assessed before and after the intervention. At the end of experiments, the ischemic cortex tissue was collected. The 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining was used to detect the volume of cerebral infarction. The expression of RORγt mRNA was detected by real-time quantitative PCR;the protein expression levels of RORγt, IL-17A, IL-10 and TGF-ß1 were detected by Western blot;the immunoactivity of IL-6 and IL-21 were detected by immunohistochemistry;the fluorescence areas of IL-17A+Th17 and FOXP3+Treg cells were measured by immunofluorescence and their ratio was calculated in the tissue of ischemic cortex. RESULTS: Relevant to the sham operation group, the model group had a significant increase in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01), and an obvious decrease in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.01). In contrast to the model group, both EA and inhibitor groups had a significant decrease in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01, P<0.05), and a marked increase in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.05, P<0.01), while the above indicators of the agonist group were all reversed (P<0.01, P<0.05). Comparison between the agonist and EA+agonist groups showed that the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg were significantly lower (P<0.01, P<0.05), and the expression of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity were obviously higher (P<0.01, P<0.05) in the EA+agonist group than in the agonist group, suggesting that EA intervention can effectively weaken the effects of RORγt agonist. CONCLUSIONS: EA of scalp acupoint MS6 can effectively improve the neurological function, behavior reaction and reduce cerebral infarct volume in ischemic stroke rats, which may be associated with its functions in down-regulating the expression of RORγt and promoting the balance of IL-17A+Th17/FOXP3+Treg to alleviate inflammatory injury after ischemic stroke.


Assuntos
Isquemia Encefálica , Eletroacupuntura , AVC Isquêmico , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Interleucina-10 , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Interleucina-17/genética , Interleucina-6 , Pontos de Acupuntura , Couro Cabeludo , Linfócitos T Reguladores , Fator de Crescimento Transformador beta1 , Infarto Cerebral , Fatores de Transcrição Forkhead , RNA Mensageiro
14.
Front Cardiovasc Med ; 11: 1344975, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414922

RESUMO

Primary pericardial angiosarcoma is a rare malignancy of the pericardium with variable clinical features and imaging characteristics. Herein, we report a case of histopathologically confirmed pericardial angiosarcoma in a 66-year-old man. The patient developed cardiac tamponade in a short time period. The transthoracic echocardiography showed the presence of multiple irregular echodensities, heterogeneous in echogenicity, encasing the apex of both ventricles in the pericardial space, initially misinterpreted as pericardial effusion. The patient died of cardiogenic shock despite undergoing a surgical pericardiectomy. Pericardial angiosarcoma can manifest as a mass obliterating the pericardial sac, rather than the typical pericardial effusion observed on echocardiography. Multimodality imaging studies aid in diagnosing primary pericardial angiosarcoma, but the final diagnosis relies on tissue histopathology.

15.
Heliyon ; 10(4): e25840, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38370187

RESUMO

Mucormycosis is an invasive opportunistic fungal infection, which may be lethal and mostly affects patients with immunodeficiency or diabetes mellitus. Among Mucorales fungi, Rhizopus spp. is the most common cause of mucormycosis, followed by genera such as Mucor and Lichtheimia. Here we report a patient with severe COVID-19 infection who developed nasal pain, facial swelling, prominent black eschar on the nasal root. CT scan revealed pansinusitis along the maxillary, ethmoidal, and sphenoid sinuses. Mixed mold infection with Rhizopus microsporus and Mucor racemosus was detected by blood metagenomics next-generation sequencing (mNGS) and later nasal mucosa histological investigation confirmed mucormycosis. Severe COVID-19 infection led to the patient's thrombocytopenia and leukopenia. Later disseminated mucormycosis aggravated the infection and sepsis eventually resulted in death. It is the first case report of mucormycosis in which R. microsporus and M. racemosus as the etiologic agents were found simultaneously in one patient. COVID-19 infection combined with disseminated mucormycosisis can be fatal and mNGS is a fast, sensitive and accurate diagnostic method for fungi detection.

16.
IEEE Trans Image Process ; 33: 1313-1325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38329844

RESUMO

Domain adaptation leverages labeled data from a source domain to learn an accurate classifier for an unlabeled target domain. Since the data collected in practical applications usually contain noise, the weakly-supervised domain adaptation algorithm has attracted widespread attention from researchers that tolerates the source domain with label noises or/and features noises. Several weakly-supervised domain adaptation methods have been proposed to mitigate the difficulty of obtaining the high-quality source domains that are highly related to the target domain. However, these methods assume to obtain the accurate noise rate in advance to reduce the negative transfer caused by noises in source domain, which limits the application of these methods in the real world where the noise rate is unknown. Meanwhile, since source data usually comes from multiple domains, the naive application of single-source domain adaptation algorithms may lead to sub-optimal results. We hence propose a universal and scalable weakly-supervised domain adaptation method called PDCAS to ease restraints of such assumptions and make it more general. Specifically, PDCAS includes two stages: progressive distillation and domain alignment. In progressive distillation stage, we iteratively distill out potentially clean samples whose annotated labels are highly consistent with the prediction of model and correct labels for noisy source samples. This process is non-supervision by exploiting intrinsic similarity to measure and extract initial corrected samples. In domain alignment stage, we consider Class-Aligned Sampling which balances the samples for both source and target domains along with the global feature distributions to alleviate the shift of label distributions. Finally, we apply PDCAS in multi-source noisy scenario and propose a novel multi-source weakly-supervised domain adaptation method called MSPDCAS, which shows the scalability of our framework. Extensive experiments on Office-31 and Office-Home datasets demonstrate the effectiveness and robustness of our method compared to state-of-the-art methods.

17.
Nat Metab ; 6(1): 18-38, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38267631

RESUMO

Cancer cells rewire their metabolism to survive during cancer progression. In this context, tumour metabolic heterogeneity arises and develops in response to diverse environmental factors. This metabolic heterogeneity contributes to cancer aggressiveness and impacts therapeutic opportunities. In recent years, technical advances allowed direct characterisation of metabolic heterogeneity in tumours. In addition to the metabolic heterogeneity observed in primary tumours, metabolic heterogeneity temporally evolves along with tumour progression. In this Review, we summarize the mechanisms of environment-induced metabolic heterogeneity. In addition, we discuss how cancer metabolism and the key metabolites and enzymes temporally and functionally evolve during the metastatic cascade and treatment.


Assuntos
Neoplasias , Humanos , Neoplasias/metabolismo
18.
Sleep ; 47(3)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38174762

RESUMO

STUDY OBJECTIVES: Narcolepsy type 1 (NT1), characterized by cataplexy and orexin deficiency, is a rare and frequently debilitating neurological disorder. It has been noted to have connections with the gut microbiota, yet the exact causal relationships remain unclear. METHODS: We conducted a comprehensive bidirectional Mendelian randomization (MR) study to rigorously investigate the causal links between the gut microbiota and NT1, utilizing genetic datasets from the MiBioGen consortium and FinnGen consortium, respectively. The inverse-variance weighted (IVW) method was employed to obtain the primary MR estimates, supplemented by several alternative methods as well as sensitivity analyses including Cochran's Q, MR-Egger, MR pleiotropy residual sum and outlier, leave-one-out, and genetic colocalization. RESULTS: Our findings indicated that an increased relative abundance of five genera including Blautia (p = 4.47E-5), Collinsella (p = 0.036), Gordonibacter (p = 0.047), Hungatella (p = 0.015), and Lachnospiraceae UCG010 (p = 0.027) may be associated with a decreased risk of NT1. Conversely, an increased relative abundance of class Betaproteobacteria (p = 0.032), genus Alloprevotella (p = 0.009), and genus Ruminiclostridium6 (p = 0.029) may potentially heighten the risk of NT1. The onset of NT1 may lead to a decrease in the relative abundance of genus Eubacterium eligens group (p = 0.022), while a increase in the family Family XI (p = 0.009), genus Hungatella (p = 0.005), genus Prevotella (p = 0.013), and unknown genus id.2001 (p = 0.019). These findings remained robust under all sensitivity analyses. CONCLUSIONS: Our results offer robust evidence for the bidirectional causal links between particular gut microbial taxa and NT1, underscoring the significance of the microbiota-gut-brain axis in the pathological process of NT1.


Assuntos
Cataplexia , Microbioma Gastrointestinal , Narcolepsia , Humanos , Microbioma Gastrointestinal/genética , Análise da Randomização Mendeliana , Narcolepsia/genética , Estudo de Associação Genômica Ampla
19.
J Am Chem Soc ; 146(5): 3363-3372, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38265366

RESUMO

Inverted organic solar cells (OSCs) have attracted much attention because of their outstanding stability, with zinc oxide (ZnO) being commonly used as the electron transport layer (ETL). However, both surface defects and the photocatalytic effect of ZnO could lead to serious photodegradation of acceptor materials. This, in turn, hampers the improvement of the efficiency and stability in OSCs. Herein, we developed a multiarmed aromatic ammonium salt, namely, benzene-1,3,5-triyltrimethanaminium bromide (PhTMABr), for modifying ZnO. This compound possesses mild weak acidity aimed at removing the residual amines present within ZnO film. In addition, the PhTMABr could also passivate surface defects of ZnO through multiple hydrogen-bonding interactions between its terminal amino groups and the oxygen anion of ZnO, leading to a better interface contact, which effectively enhances charge transport. As a result, an efficiency of 18.75% was achieved based on the modified ETL compared to the bare ZnO (PCE = 17.34%). The devices utilizing the modified ZnO retained 87% and 90% of their initial PCE after thermal stress aging at 65 °C for 1500 h and continuous 1-sun illumination with maximum power point (MPP) tracking for 1780 h, respectively. Importantly, the extrapolated T80 lifetime with MPP tracking exceeds 10 000 h. The new class of materials employed in this work to modify the ZnO ETL should pave the way for enhancing the efficiency and stability of OSCs, potentially advancing their commercialization process.

20.
Nat Prod Res ; 38(10): 1704-1710, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37254867

RESUMO

Two new aporphine-derived alkaloids, aporaloids C and D (1 and 2), along with eight known biogenetically related alkaloids (3-10) were isolated from the stems of Fissistigma maclurei Merr. Their structures were elucidated by detailed analysis of NMR, HRESIMS, MS, IR, UV and Optical rotations data. Compounds 1 and 2 represent a rare example of N-methylol aporphine-derived alkaloids from natural sources. The inhibitory effect of all compounds on the proliferation of primary synovial cells was evaluated. Compound 3 showed potent inhibitory effect on the proliferation of synoviocytes with an IC50 value of 4.8 µM. Compounds 1, 2, 6-9 and 10 exhibited moderate inhibitory activity on synoviocytes, with IC50 values of 36.8, 37.1, 31.2 µM, 32.5, 36.3, 36.8 and 18.2 µM, respectively.


Assuntos
Alcaloides , Annonaceae , Aporfinas , Sinoviócitos , Annonaceae/química , Estrutura Molecular , Alcaloides/química , Aporfinas/química , Proliferação de Células
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA