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1.
Int J Biol Macromol ; 185: 513-524, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34214575

RESUMO

It remains a great challenge to prepare polylactic acid (PLA) composites with excellent mechanical properties, superior anti-bacteria, and highly effective electromagnetic interference (EMI) shielding using ultralow loading of functional fillers. Herein, lignin particles were uniformly nano-sized as the matrix reinforcement and the fillers carrier via green mechanochemistry for improved thermal properties of polymer matrix. Through one-pot approach to a multitasking engineered agent, hybridized ZnO/Ag particles were synthesized for multi-functionalities. Inspired by mussels, the bio-derived dopamine cross-linker was introduced to in-situ synthesize the polypyrrole (PPy-PDa) glutinous nanofibrils as an interfacial modifier and a particles dispersant to regulate surface free energy of nanoparticles and improve filler-matrix interactions. With effective constructed 3D conductive networks by glutinous nanofibrils and hybridized particles, the dramatic improvement in EMI shielding and electrical conductivity was accomplished using an ultralow content of the conductive particles modifier (0.29 vol% Ag). The resulted biobased composites presented outstanding anti-dripping properties, mechanical properties, electrical conductivity (104.2 S/cm), anti-bacteria, joule heating, photothermal conversion ability and EMI shielding effectiveness (48.6 dB at X-band), which are superior to those reported. This work will broaden the application prospects of PLA composites in the fields of wearable electronics, food packaging and medical devices.

2.
BMC Cancer ; 21(1): 792, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238262

RESUMO

BACKGROUND: The effects of adjuvant chemotherapy in patients with stage II colorectal cancer (CRC) has been in controversy for a long time. Our study aimed to find an effective inflammatory marker to predict the effects of chemotherapy. METHODS: Seven hundred eight stage II CRC patients in our institution were included. The subpopulation treatment effect pattern plot (STEPP) analysis was used to determine the optimal inflammatory marker and cut-off value. Propensity score matching (PSM) was performed to balance discrepancy between the chemotherapy and non-chemotherapy group. Survival analyses based on overall survival (OS) and cancer-specific survival (CSS) were performed with Kaplan-Meier methods with log-rank test and Cox proportional hazards regression. The restricted mean survival time (RMST) was used to measure treatment effect. RESULTS: The platelet to lymphocyte ratio (PLR) was chosen as the optimal marker with a cut-off value of 130 according to STEPP. In OS analysis, PLR was significantly associated with the effects of chemotherapy (interaction p = 0.027). In the low-PLR subgroup, the chemotherapy patients did not have a longer OS than the non-chemotherapy patients (HR: 0.983, 95% CI: 0.528-1.829). In the high-PLR subgroup, the chemotherapy patients had a significantly longer OS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212-0.649). After PSM, PLR was still associated with the effects of chemotherapy. In CSS analysis, PLR was not significantly associated with the effects of chemotherapy (interaction p = 0.116). In the low-PLR subgroup, the chemotherapy patients did not have a longer CSS than the non-chemotherapy patients (HR: 1.016, 95% CI: 0.494-2.087). In the high-PLR subgroup, the chemotherapy patients had a longer CSS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212-0.649). After PSM, PLR was not associated with the effects of chemotherapy. CONCLUSIONS: PLR is an effective marker to predict the effects of chemotherapy in patients with stage II CRC.

4.
J Hazard Mater ; 417: 126041, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229381

RESUMO

Simultaneous conversion of most harmful As(III) and Cr(VI) to their less toxic counterparts is environmentally desirable and cost-effective. It has been confirmed that simultaneous oxidation of As(III) to As(V) and reduction of Cr(VI) to Cr(III) can occur via free radical or mediated electron transfer processes. While Cr(VI) is reduced by reacting with H•, eaq-, photoelectron directly or undergoing ligand exchange with H2O2 and SO32-, As(III) is oxidized by HO•, SO4•-, O2•-, and holes (h+) in free radical process. The ability to concentrate Cr and As species on heterogeneous interface and conductivity determining the co-conversion efficiency in mediated electron transfer process. Acidity has positive effect on these co-conversion, while mediated electron transfer process is not much affected by dissolved oxygen (O2). Organic compounds (e.g., oxalate, citrate and phenol) commonly favor Cr(VI) reduction and inhibit As(III) oxidation. To better understand the trends in the existing data and to identify the knowledge gaps, this review elaborates the complicated mechanisms for co-conversion of As(III) and Cr(VI) by various methods. Some challenges and prospects in this active field are also briefly discussed.

5.
BMC Plant Biol ; 21(1): 338, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271854

RESUMO

BACKGROUND: Mulberry (Morus alba L.) is an important sericulture crop; however, root-knot nematode infection seriously limits its production. Understanding the mechanism of interaction between mulberry and nematode is important for control of infection. RESULTS: Using sequencing and de novo transcriptome assembly, we identified 55,894 unigenes from root samples of resistant and susceptible mulberry cultivars at different stages after infection with the nematode Meloidogyne enterolobii; 33,987 of these were annotated in the Nr, SWISS-PROT, KEGG, and KOG databases. Gene ontology and pathway enrichment analyses of differentially expressed genes (DEGs) revealed key genes involved in hormone metabolic processes, plant hormone signal transduction, flavonoid biosynthesis, phenylpropanoid biosynthesis, and peroxisomal and photosynthetic pathways. Analysis of key trends in co-expression networks indicated that expression of unigenes 0,015,083, 0,073,272, 0,004,006, and 0,000,628 was positively correlated with resistance to M. enterolobii. Unigene 0015083 encodes tabersonine 16-O-methyltransferase (16OMT), which is involved in alkaloid biosynthesis. Unigene 0073272 encodes a transcription factor contributing to nitric oxide accumulation during plant immune responses. Unigenes 0,004,006 and 0,000,628 encode ERF and MYB transcription factors, respectively, involved in plant hormone signaling. We verified the accuracy of transcriptome sequencing results by RT-qPCR of 21 DEGs. CONCLUSIONS: The results of this study increase our understanding of the resistance mechanisms and candidate genes involved in mulberry-M. enterolobii interaction. Thus, our data will contribute to the development of effective control measures against this pathogen.

6.
Phytomedicine ; 90: 153627, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34247115

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disorder prevalent in the aged population. Tetrandrine is a natural metabolite isolated from herbal medicine Stephania tetrandra with various activities. PURPOSE: In this study, we investigated the therapeutic role of tetrandrine in 5XFAD mouse, a transgenic model of AD. METHODS: 5XFAD mice were intraperitoneally injected with saline or different doses of tetrandrine (10, 20, and 40 mg/kg per 2 days) from the age of 5 months to 7 months followed by the determination of cognitive ability, amyloid plaque load, cell apoptosis, and inflammation in the brain. In vitro, the protective roles of tetrandrine against inflammatory activation of microglia and the resulting neurotoxicity were studied in BV2 cells and differentiated PC12 cells, respectively. RESULTS: Morris water maze test showed that two months of tetrandrine treatment dose-dependently improved the cognitive ability of 5XFAD mice. Immunostaining against Aß 1-42 demonstrated reduced amyloid plaque deposition in the brain of tetrandrine-treated 5XFAD mice. TUNEL assay revealed decreased cell apoptosis in the hippocampus after tetrandrine treatment. Further, RT-PCR showed that the ectopic transcription of inflammation-associated genes including TNFα, IL-1ß, IL-6, COX-2, iNOS, and p65 was reversed in 5XFAD mice treated with tetrandrine. In vitro, Aß 1-42 stimulated the secretion of inflammatory cytokines TNFα and IL-1ß in microglial BV2 cells as determined by ELISA, which was suppressed by tetrandrine pre-treatment. Tetrandrine pre-treatment also inhibited the expression of TLR4, p65, iNOS, and COX-2 in BV2 cells induced by Aß 1-42. Most importantly, treatment of PC12-derived neuron-like cells with conditional medium from Aß 1-42-stimulated BV2 cells remarkably impaired cell viability and promoted cell apoptosis, which was attenuated by the conditional medium from BV2 cells with tetrandrine pre-treatment. CONCLUSION: Collectively, findings in this study demonstrated that tetrandrine ameliorates AD by suppressing microglia-mediated inflammation and neurotoxicity.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34232895

RESUMO

In medical image analysis, in order to reduce the impact of unbalanced data sets on data-driven deep learning models, according to the characteristic that the area under the Precision-Recall curve (AUCPR) is sensitive to each category of samples, a novel Harmony loss function with fast convergence speed and high stability was constructed. Since AUCPR needs to be calculated in discrete domain, in order to ensure the continuous differentiability and gradient existence of the Harmony loss, first, the Logistic function was used to approximate the Logical function in AUCPR. Then, to improve the optimization speed of the Harmony loss during model training, a method of manually setting a certain number of classification thresholds was proposed to further approximate the calculation of AUCPR. After the above two approximate calculation processes, the Harmony loss with stable gradient and high computational efficiency was designed. In the optimization process of the model, since Harmony loss can reconcile recall and precision of each category under different classification thresholds, thereby, it can not only improve the models ability to recognize categories with less samples, but also maintain the stability of the training curve. To comprehensively evaluate the effects of Harmony loss function, we performed experiments on image 3D reconstruction, 2D segmentation, and unbalanced classification tasks. Experimental results showed that the Harmony loss achieved the state-of-the-art results on four unbalanced data sets. Moreover, the Harmony loss can be easily combined with existing loss functions, and is suitable for most common deep learning models.

8.
Nanotechnology ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233312

RESUMO

For decades, lab-on-fiber (LOF) sensing systems have become an emerging optical sensing platform due to the features of small size and light weight. Herein, a simple and efficient in-situ construction strategy was reported for the preparation of LOF sensing platform based on the integration of responsive Fabry-Perot optical resonance cavity on optical fibers. The responsive Fabry-Perot optical resonance cavity with thermal poly(N-isopropylacrylamide) (PNIPAm) polymer brush layer sandwiched by two silver layers was constructed on the end surface of the optical fiber through combining in-situ surface-initiated polymerization and metal film deposition techniques. Owing to the thermo-responsiveness of the intermediate layer, the as-prepared LOF sensing system shows a sensitive response towards the environmental temperature. Importantly, the as-prepared LOF sensing system also possesses excellent repeatability and rapid response rate. Together with the features of high sensitivity, excellent repeatability and rapid response rate, we believe such LOF sensing system will provide a foundation for the future applications of medical diagnosis, in-vivo detection and public security.

9.
ANZ J Surg ; 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224199

RESUMO

BACKGROUND: An updated meta-analysis was performed on the significance of preoperative jaundice in the surgical management of gallbladder carcinoma (GBC). METHODS: A thorough database searching was performed in PubMed, EMBASE, and the Cochrane library for comparative studies between jaundiced and non-jaundiced GBC patients. RevMan5.3 and Stata 13.0 software were used for statistical analysis. A total of nine measured outcomes were identified: resectability, R0 resection rate, concurrent bile duct resection, major hepatectomy, vital vascular reconstruction, combined adjacent organ resections, postoperative morbidities, mortalities, and overall survival (OS). RESULTS: A total of eight studies were finally included. Newcastle- Ottawa Quality Assessment Scale was used for evaluating the quality of all included studies and the details were recorded in Table S1. Our pooled results revealed that preoperative jaundice was associated with a significantly lower resectability (p < 0.00001), a significantly lower R0 resection rate (p < 0.00001), a significantly higher concurrent bile duct resection rate (p < 0.00001), major hepatectomy rate (≥3 segments) (p < 0.00001), and vital vascular reconstruction rate (portal vein or hepatic artery) (p < 0.00001). Moreover, jaundiced patients experienced more postoperative morbidities (p < 0.00001), mortalities (p < 0.0001), and worse OS (p < 0.00001). However, jaundice was not related to combined adjacent organ resections (p = 0.58). CONCLUSION: Preoperative jaundice in GBC patients seems to be contraindicated to curative resection and the optimal therapeutic strategies should be identified via multidisciplinary team rather than surgery alone. Candidates for curative surgery should be highly selected and experienced centers are preferred. More significant well-designed studies are required for further exploration.

10.
Schizophr Res ; 233: 89-96, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34246865

RESUMO

OBJECTIVE: The symptom-related neurobiology characteristic of schizophrenia in the brain from a network perspective is still poorly understood, leading to a lack of potential biologically-based markers and difficulty identifying therapeutic targets. We aim to test the dysregulated cross-network interactions among the Salience Network (SN), Central Executive Network (CEN) and Default Mode Network (DMN) and how they contributed to different symptoms in schizophrenia patients. METHODS: We examined network interactions among the SN, CEN and DMN in 76 patients with schizophrenia vs. 80 well-matched controls using dynamic causal modeling (DCM). We further analyzed the relation between network dynamics and Positive and Negative Syndrome Scale (PANSS). RESULTS: We observed that the DMN, CEN and SN across healthy controls and schizophrenia patients showed several similarities within or between-network pattern in the resting state. Comparing schizophrenia to controls, SN-centered cross-network interactions were most significantly reduced. Crucially, the strength of connections from CEN subnetwork 1 to DMN subnetwork 1 was positively correlated with the Positive Score of PANSS. The connection from the DMN subnetwork 2 to CEN subnetwork 2 was negatively correlated with the Negative Score of PANSS. CONCLUSIONS: Our study provides strong evidence for the dysregulation among SN, CEN and DMN in a triple-network perspective in schizophrenia. The connection between DMN and CEN could be clinically-relevant neurobiological signature of schizophrenia symptoms. Our study indicated that the description of brain triple network hypothesis could be a novel and possible bio-marker for schizophrenia.

11.
Int J Infect Dis ; 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34217874

RESUMO

INTRODUCTION AND AIMS: Meningitis in neonates and young infants leads to significant morbidity and mortality worldwide. This study aims to investigate pathogens, antibiotics resistance and secular change of incidence in Hong Kong. METHODS: We performed a retrospective search on meningitis in neonates and infants <3 months old in three Hong Kong public hospitals from 2004 to 2019. Medical charts were reviewed, focusing on the identification and antibiotics resistance of the pathogens. RESULTS: 200 cases of meningitis were identified (67% were bacterial). Group B Streptococcus (GBS) and Escherichia coli (E. coli) were the commonest bacterial pathogens. The annual rates of early-onset GBS meningitis decreased since the implementation of the universal GBS screening and intrapartum antibiotics prophylaxis (IAP) in 2012, while that of late-onset GBS meningitis remained similar. A significant portion of E. coli isolates were resistant to ampicillin and/or gentamicin. CONCLUSION: GBS and E. coli remained the commonest bacteria for meningitis in this age group. The annual rate of bacterial meningitis in Hong Kong declined in recent years, which was attributed by the decline in that of early-onset GBS meningitis due to the universal GBS screening and IAP. Antimicrobial-resistant bacterial strains that caused meningitis require further clinical and public health attention.

12.
Front Immunol ; 12: 692051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194440

RESUMO

The meningeal lymphatic vessels (mLVs) in central nervous system (CNS) have been validated by rodent and human studies. The mLVs play a vital role in draining soluble molecules and trafficking lymphocytes, antigens and antibodies from CNS into cervical lymph nodes (CLNs). This indicates that mLVs may serve as a link between the CNS and peripheral immune system, perhaps involving in the neuroinflammatory disease. However, the morphology and drainage function of mLVs in patients with neuroinflammatory disease, such as neuromyelitis optica spectrum disorders (NMOSD), remains unexplored. Using the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), we found that slower flow through mLVs along superior sagittal sinus in NMOSD patients with acute attack instead of NMOSD patients in chronic phase. The reduced flow in mLVs correlated with the disease severity evaluated by expanded disability status scale (EDSS). The receiver operating characteristic curve (ROC) indicated DCE-MRI might provide objective evidence to predict the acute relapse of NMOSD through evaluating the function of mLVs. Promoting or restoring the function of mLVs might be a new target for the treatment of NMOSD relapse.

13.
Fitoterapia ; 153: 104949, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34087408

RESUMO

Illicium difengpi is well-known as its stem barks that have been widely used in the Traditional Chinese Medicine (TCM) for therapy rheumatoid arthritis and traumatic injury. To comprehensive utilization of resources, the phytochemical investigation on the branches and leaves of this plant was carried out, which led to the isolation of an undescribed neolignan along with three known lignans. Their structures were elucidated on the basis of extensive spectroscopic data and the new compound was elucidated as a neolignan possessing a dihydropyran ring formed by a unique conjugation way and named difengpienol C. Difengpienol C showed the strongest anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, which powerfully inhibited nitric oxide (NO), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) production and suppressed the mRNA transcription of inducible nitric oxide synthase (iNOS), IL-6 and TNF-α. Besides, difengpienol C blocked the activation of TLR4/MyD88/NF-κB signaling pathway. Therefore, difengpienol C might be a potent agent for anti-inflammatory drug development, and the non-traditional medicinal parts of Illicium difengpi can be identified as the source of natural anti-inflammatory molecules.

14.
Cell Death Dis ; 12(6): 596, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108448

RESUMO

Mesenchymal stem cell transplantation (MSCT) has been recognized as a potent and promising approach to achieve immunomodulation and tissue regeneration, but the mechanisms of how MSCs exert therapeutic effects remain to be elucidated. Increasing evidence suggests that transplanted MSCs only briefly remain viable in recipients, after which they undergo apoptosis in the host circulation or in engrafted tissues. Intriguingly, apoptosis of infused MSCs has been revealed to be indispensable for their therapeutic efficacy, while recipient cells can also develop apoptosis as a beneficial response in restoring systemic and local tissue homeostasis. It is notable that apoptotic cells produce apoptotic extracellular vesicles (apoEVs), traditionally known as apoptotic bodies (apoBDs), which possess characterized miRnomes and proteomes that contribute to their specialized function and to intercellular communication. Importantly, it has been demonstrated that the impact of apoEVs is long-lasting in health and disease contexts, and they critically mediate the efficacy of MSCT. In this review, we summarize the emerging understanding of apoptosis in mediating MSCT, highlighting the potential of apoEVs as cell-free therapeutics.

15.
J Am Chem Soc ; 143(27): 10352-10360, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34161068

RESUMO

The direct difunctionalization of alkenes is an effective way to construct multiple C-C bonds in one-pot using a single functional group. The regioselective dicarbofunctionalization of alkenes is therefore an important area of research to rapidly obtain complex organic molecules. Herein, we report a palladium-catalyzed γ,γ'-diarylation of free alkenyl amines through interrupted chain walking for the synthesis of Z-selective alkenyl amines. Notably, while 1,3-dicarbofunctionalization of allyl groups is well precedented, the present disclosure allows 1,3-dicarbofunctionalization of highly substituted allylamines to give highly Z-selective trisubsubstituted olefin products. This cascade reaction operates via an unprotected amine-directed Mizoroki-Heck (MH) pathway featuring a ß-hydride elimination to selectively chain walk to furnish a new terminal olefin which then generates the cis-selective alkenyl amines around the sterically crowded allyl moiety. This operationally simple protocol is applicable to a variety of cyclic, branched, and linear secondary and tertiary alkenylamines, and has a broad substrate scope with regard to the arene coupling partner as well. Mechanistic studies have been performed to help elucidate the mechanism, including the presence of a likely unproductive side C-H activation pathway.

16.
Nat Commun ; 12(1): 3501, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: covidwho-1263489

RESUMO

The characteristics of COVID-19 patients with persistent SARS-CoV-2 infection are not yet well described. Here, we compare the clinical and molecular features of patients with long duration of viral shedding (LDs) with those from patients with short duration patients (SDs), and healthy donors (HDs). We find that several cytokines and chemokines, such as interleukin (IL)-2, tumor necrosis factor (TNF) and lymphotoxin α (LT-α) are present at lower levels in LDs than SDs. Single-cell RNA sequencing shows that natural killer (NK) cells and CD14+ monocytes are reduced, while regulatory T cells are increased in LDs; moreover, T and NK cells in LDs are less activated than in SDs. Importantly, most cells in LDs show reduced expression of ribosomal protein (RP) genes and related pathways, with this inversed correlation between RP levels and infection duration further validated in 103 independent patients. Our results thus indicate that immunosuppression and low RP expression may be related to the persistence of the viral infection in COVID-19 patients.


Assuntos
COVID-19/imunologia , SARS-CoV-2/patogenicidade , Linfócitos B/metabolismo , Linfócitos B/patologia , COVID-19/virologia , Citocinas/sangue , Perfilação da Expressão Gênica , Humanos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Leucócitos Mononucleares/patologia , Ativação Linfocitária/genética , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/patologia , Proteínas Ribossômicas/genética , SARS-CoV-2/isolamento & purificação , Transdução de Sinais/genética , Linfócitos T/metabolismo , Linfócitos T/patologia , Eliminação de Partículas Virais
17.
Front Immunol ; 12: 659419, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1256378

RESUMO

Highly pathogenic virus infections usually trigger cytokine storms, which may have adverse effects on vital organs and result in high mortalities. The two cytokines interleukin (IL)-4 and interferon (IFN)-γ play key roles in the generation and regulation of cytokine storms. However, it is still unclear whether the cytokine with the largest induction amplitude is the same under different virus infections. It is unknown which is the most critical and whether there are any mathematical formulas that can fit the changing rules of cytokines. Three coronaviruses (SARS-CoV, MERS-CoV, and SARS-CoV-2), three influenza viruses (2009H1N1, H5N1 and H7N9), Ebola virus, human immunodeficiency virus, dengue virus, Zika virus, West Nile virus, hepatitis B virus, hepatitis C virus, and enterovirus 71 were included in this analysis. We retrieved the cytokine fold change (FC), viral load, and clearance rate data from these highly pathogenic virus infections in humans and analyzed the correlations among them. Our analysis showed that interferon-inducible protein (IP)-10, IL-6, IL-8 and IL-17 are the most common cytokines with the largest induction amplitudes. Equations were obtained: the maximum induced cytokine (max) FC = IFN-γ FC × (IFN-γ FC/IL-4 FC) (if IFN-γ FC/IL-4 FC > 1); max FC = IL-4 FC (if IFN-γ FC/IL-4 FC < 1). For IFN-γ-inducible infections, 1.30 × log2 (IFN-γ FC) = log10 (viral load) - 2.48 - 2.83 × (clearance rate). The clinical relevance of cytokines and their antagonists is also discussed.


Assuntos
Síndrome da Liberação de Citocina/imunologia , Citocinas/sangue , Modelos Imunológicos , Viroses/complicações , Biomarcadores/sangue , Biomarcadores/metabolismo , Síndrome da Liberação de Citocina/sangue , Síndrome da Liberação de Citocina/diagnóstico , Síndrome da Liberação de Citocina/virologia , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Carga Viral/imunologia , Viroses/sangue , Viroses/imunologia , Viroses/virologia
18.
Artigo em Inglês | MEDLINE | ID: covidwho-1276481

RESUMO

The novel 2019 Coronavirus (COVID-19) infection has spread worldwide and is currently a major healthcare challenge around the world. Chest computed tomography (CT) and X-ray images have been well recognized to be two effective techniques for clinical COVID-19 disease diagnoses. Due to faster imaging time and considerably lower cost than CT, detecting COVID-19 in chest X-ray (CXR) images is preferred for efficient diagnosis, assessment, and treatment. However, considering the similarity between COVID-19 and pneumonia, CXR samples with deep features distributed near category boundaries are easily misclassified by the hyperplanes learned from limited training data. Moreover, most existing approaches for COVID-19 detection focus on the accuracy of prediction and overlook uncertainty estimation, which is particularly important when dealing with noisy datasets. To alleviate these concerns, we propose a novel deep network named RCoNetks for robust COVID-19 detection which employs Deformable Mutual Information Maximization (DeIM), Mixed High-order Moment Feature (MHMF), and Multiexpert Uncertainty-aware Learning (MUL). With DeIM, the mutual information (MI) between input data and the corresponding latent representations can be well estimated and maximized to capture compact and disentangled representational characteristics. Meanwhile, MHMF can fully explore the benefits of using high-order statistics and extract discriminative features of complex distributions in medical imaging. Finally, MUL creates multiple parallel dropout networks for each CXR image to evaluate uncertainty and thus prevent performance degradation caused by the noise in the data. The experimental results show that RCoNetks achieves the state-of-the-art performance on an open-source COVIDx dataset of 15,134 original CXR images across several metrics. Crucially, our method is shown to be more effective than existing methods with the presence of noise in the data.

20.
Biochem Pharmacol ; 190: 114664, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34175300

RESUMO

Transient receptor potential melastatin (TRPM) channels are members of the transient receptor potential (TRP) channels, a family of evolutionarily conserved integral membrane proteins. TRPM channels are nonselective cation channels, mediating the influx of various ions including Ca2+, Na+ and Zn2+. The function of TRPM channels is vital for cell proliferation, cell development and cell death. Cell death is a key procedure during embryonic development, organism homeostasis, aging and disease. The category of cell death modalities, beyond the traditionally defined concepts of necrosis, autophagy, and apoptosis, were extended with the discovery of pyroptosis, necroptosis and ferroptosis. As upstream signaling regulators of cell death, TRPM channels have been involved inrelevant pathologies. In this review, we introduced several cell death modalities, then summarized the contribution of TRPM channels (especially TRPM2 and TRPM7) to different cell death modalities and discussed the underlying regulatory mechanisms. Our work highlighted the possibility of TRPM channels as potential therapeutic targets in cell death-related diseases.

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