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1.
Biomaterials ; 312: 122709, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39094521

RESUMO

Sonodynamic therapy (SDT) relies heavily on the presence of oxygen to induce cell death. Its effectiveness is thus diminished in the hypoxic regions of tumor tissue. To address this issue, the exploration of ultrasound-based synergistic treatment modalities has become a significant research focus. Here, we report an ultrasonic cavitation effect enhanced sonodynamic and 1208 nm photo-induced cancer treatment strategy based on thermoelectric/piezoelectric oxygen-defect bismuth oxychloride nanosheets (BNs) to realize the high-performance eradication of tumors. Upon ultrasonic irradiation, the local high temperature and high pressure generated by the ultrasonic cavitation effect combined with the thermoelectric and piezoelectric effects of BNs create a built-in electric field. This facilitates the separation of carriers, increasing their mobility and extending their lifetimes, thereby greatly improving the effectiveness of SDT and NIR-Ⅱ phototherapy on hypoxia. The Tween-20 modified BNs (TBNs) demonstrate ∼88.6 % elimination rate against deep-seated tumor cells under hypoxic conditions. In vivo experiments confirm the excellent antitumor efficacy of TBNs, achieving complete tumor elimination within 10 days with no recurrences. Furthermore, due to the high X-ray attenuation of Bi and excellent NIR-Ⅱ absorption, TBNs enable precise cancer diagnosis through photoacoustic (PA) imaging and computed tomography (CT).


Assuntos
Bismuto , Neoplasias da Mama , Oxigênio , Terapia por Ultrassom , Bismuto/química , Feminino , Animais , Neoplasias da Mama/terapia , Terapia por Ultrassom/métodos , Oxigênio/química , Camundongos , Camundongos Endogâmicos BALB C , Humanos , Linhagem Celular Tumoral , Raios Infravermelhos , Nanoestruturas/química , Fototerapia/métodos
2.
J Gastrointest Oncol ; 15(4): 1686-1697, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39279926

RESUMO

Background: Vascular invasion is a major risk factor for poor prognosis of liver transplantation (LT) for hepatocellular carcinoma (HCC), and this study aimed to evaluate the feasibility and efficacy of deceased donor LT (DDLT) for the treatment of microvascular invasion (MVI) and segmental portal vein tumor thrombus (PVTT). Methods: We retrospectively analyzed 141 patients who received DDLT for HCC combined with vascular invasion from January 2016 to December 2023 at Shulan (Hangzhou) Hospital. To assess the risk of vascular invasion associated with the LT prognosis, we evaluated various clinicopathologic variables. The recurrence-free survival (RFS) and overall survival (OS) based on different types of vascular invasion were also analyzed. Results: A total of 141 patients were enrolled in this study, including patients with MVI (MVI group, n=60), segmental PVTT with segmental branches of the portal vein or above (segmental PVTT group, n=13), and lobar PVTT involving the left and right branches of the portal vein or the main portal vein (lobar PVTT group, n=68). Between the tumor recurrence group and the no recurrence group, there were significant differences in alpha-fetoprotein (AFP) level, tumor total diameter, pretransplant treatment, histological grade, and types of vascular invasion. Subgroup analyses were performed according to the types of vascular invasion, the lobar PVTT group had a significantly higher recurrence rate (lobar vs. MVI: 88.2% vs. 35.0%, lobar vs. segmental: 88.2% vs. 30.8%, both P<0.001), but there was no difference in recurrence rate between the MVI group and the segmental PVTT group (35.0% vs. 30.8%, P>0.99). The 3-year RFS rate and OS rate were as low as 9.1% and 45.9% in the lobar PVTT group, compared with 65.5% and 76.0% in the MVI group, 58.3% and 75.0% in the segmental PVTT group. Multivariate analysis showed that Child-Pugh classification, tumor total diameter, histological grade, and lobar PVTT were the main risk factors affecting RFS, whereas Child-Pugh classification, tumor total diameter, and lobar PVTT were the main risk factors affecting OS. Finally, analysis of the segmental PVTT group revealed that RFS was significantly higher in well and moderately-differentiated patients than in poor-differentiated patients (P=0.01). Conclusions: Lobar PVTT remains a contraindication to LT, whereas segmental PVTT can still be considered for LT after careful screening.

3.
BMJ Open ; 14(9): e085733, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39260857

RESUMO

OBJECTIVE: Pulmonary tuberculosis (PTB) is a critical challenge worldwide, particularly in China. This study aimed to explore the spatiotemporal transmission patterns and socioeconomic factors of PTB in Dongguan city, China. METHODS/DESIGN: An ecological study based on the reported new PTB cases between 2011 and 2020 was conducted in Dongguan city, China. The spatiotemporal analysis methods were used to explore the long-term trend, spatiotemporal transmission pattern and socioeconomic factors of PTB. MAIN OUTCOME MEASURES: The number of new PTB cases. PARTICIPANTS: We collected 35 756 new PTB cases, including 23 572 males and 12 184 females. RESULTS: The seasonal-trend decomposition indicated a significant downward trend for PTB with a significant peak in 2017 and 2018, and local spatial autocorrelation showed more and more high-high clusters in the central and north-central towns with high incidence. The multivariate spatial time series analysis revealed that the endemic component had a leading role in driving PTB transmission, with a high total effect value being 189.40 (95% CI: 171.65-207.15). A Bayesian spatiotemporal model revealed that PTB incidence is positively associated with the agricultural population ratio (relative risk (RR) =1.074), gender ratio (RR=1.104) and the number of beds in medical institutions (RR=1.028). CONCLUSIONS: These findings revealed potential spatiotemporal variability and spatial aggregation of PTB, so targeted preventive strategies should be made in different towns based on spatiotemporal transmission patterns and risk factors.


Assuntos
Fatores Socioeconômicos , Análise Espaço-Temporal , Tuberculose Pulmonar , Humanos , Tuberculose Pulmonar/epidemiologia , China/epidemiologia , Feminino , Masculino , Adulto , Incidência , Pessoa de Meia-Idade , Teorema de Bayes , Adulto Jovem , Fatores de Risco , Adolescente , Idoso
4.
Biomolecules ; 14(8)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39199334

RESUMO

The interaction between microbes and drugs encompasses the sourcing of pharmaceutical compounds, microbial drug degradation, the development of drug resistance genes, and the impact of microbial communities on host drug metabolism and immune modulation. These interactions significantly impact drug efficacy and the evolution of drug resistance. In this study, we propose a novel predictive model, termed GCGACNN. We first collected microbe, disease, and drug association data from multiple databases and the relevant literature to construct three association matrices and generate similarity feature matrices using Gaussian similarity functions. These association and similarity feature matrices were then input into a multi-layer Graph Neural Network for feature extraction, followed by a two-dimensional Convolutional Neural Network for feature fusion, ultimately establishing an effective predictive framework. Experimental results demonstrate that GCGACNN outperforms existing methods in predictive performance.


Assuntos
Redes Neurais de Computação , Humanos , Preparações Farmacêuticas/metabolismo , Algoritmos , Algoritmo Florestas Aleatórias
5.
IEEE Trans Med Imaging ; PP2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088492

RESUMO

Semi-supervised learning (SSL) has been proven beneficial for mitigating the issue of limited labeled data, especially on volumetric medical image segmentation. Unlike previous SSL methods which focus on exploring highly confident pseudo-labels or developing consistency regularization schemes, our empirical findings suggest that differential decoder features emerge naturally when two decoders strive to generate consistent predictions. Based on the observation, we first analyze the treasure of discrepancy in learning towards consistency, under both pseudo-labeling and consistency regularization settings, and subsequently propose a novel SSL method called LeFeD, which learns the feature-level discrepancies obtained from two decoders, by feeding such information as feedback signals to the encoder. The core design of LeFeD is to enlarge the discrepancies by training differential decoders, and then learn from the differential features iteratively. We evaluate LeFeD against eight state-of-the-art (SOTA) methods on three public datasets. Experiments show LeFeD surpasses competitors without any bells and whistles, such as uncertainty estimation and strong constraints, as well as setting a new state of the art for semi-supervised medical image segmentation. Code has been released at https://github.com/maxwell0027/LeFeD.

6.
Br J Hosp Med (Lond) ; 85(8): 1-15, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212565

RESUMO

Aims/Background: The coronavirus disease 2019 (COVID-19) pandemic has highlighted the need for accurate and efficient diagnostic methods. This study aims to improve COVID-19 detection by integrating chest X-ray (CXR) and computerized tomography (CT) images using deep learning techniques, further improving diagnostic accuracy by using a combined imaging approach. Methods: The study used two publicly accessible databases, COVID-19 Questionnaires for Understanding the Exposure (COVID-QU-Ex) and Integrated Clinical and Translational Cancer Foundation (iCTCF), containing CXR and CT images, respectively. The proposed system employed convolutional neural networks (CNNs) for classification, specifically EfficientNet and ResNet architectures. The data underwent preprocessing steps, including image resizing, Gaussian noise addition, and data augmentation. The dataset was divided into training, validation, and test sets. Gradient-weighted Class Activation Mapping (Grad-CAM) was used for model interpretability. Results: The EfficientNet-based models outperformed the ResNet-based models across all metrics. The highest accuracy achieved was 99.44% for CXR images and 99.81% for CT images with EfficientNetB5. The models also demonstrated high precision, recall, and F1 scores. For statistical significance, the p-values were less than 0.05, indicating that the results are significant. Conclusion: Integrating CXR and CT images using deep learning significantly improves the accuracy of COVID-19 diagnosis. The EfficientNet-based models, with their superior feature extraction capabilities, show better performance than ResNet models. Grad-CAM Visualizations provide insights into the model's decision-making process, potentially reducing diagnostic errors and accelerating diagnosis processes. This approach can improve patient care and support healthcare systems in managing the pandemic more effectively.


Assuntos
COVID-19 , Aprendizado Profundo , Radiografia Torácica , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Humanos , COVID-19/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Radiografia Torácica/métodos , Redes Neurais de Computação
7.
World J Gastrointest Oncol ; 16(6): 2476-2486, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994164

RESUMO

BACKGROUND: The objectives of this study were to assess the safety and efficacy of drug-eluting bead transarterial chemoembolization (DEB-TACE) as neoadjuvant therapy before liver transplantation (LT) for advanced-stage hepatocellular carcinoma (HCC) and to analyze the prognostic factors. AIM: To determine whether DEB-TACE before LT is superior to LT for advanced-stage HCC. METHODS: A total of 99 individuals diagnosed with advanced HCC were studied retrospectively. The participants were categorized into the following two groups based on whether they had received DEB-TACE before LT: DEB-TACE group (n = 45) and control group (n = 54). The participants were further divided into two subgroups based on the presence or absence of segmental portal vein tumor thrombus (PVTT). The DEB-TACE group consisted of two subgroups: Group A (n = 31) without PVTT and group B (n = 14) with PVTT. The control group also had two subgroups: Group C (n = 37) without PVTT and group D (n = 17) with PVTT. Data on patient demographics, disease characteristics, therapy response, and adverse events (AEs) were collected. The overall survival (OS) and recurrence-free survival (RFS) rates were assessed using Kaplan-Meier curves. Univariate and multivariate Cox regression analyses were conducted to determine the parameters that were independently related to OS and RFS. RESULTS: The DEB-TACE group exhibited an overall response rate of 86.6%. Following therapy, there was a significant decrease in the median alpha-fetoprotein (AFP) level (275.1 ng/mL vs 41.7 ng/mL, P < 0.001). The main AE was post-embolization syndrome. The 2-year rates of RFS and OS were significantly higher in the DEB-TACE group than in the control group (68.9% vs 38.9%, P = 0.003; 86.7% vs 63.0%, P = 0.008). Within the subgroups, group A had higher 2-year rates of RFS and OS compared to group C (71.0% vs 45.9%, P = 0.038; 83.8% vs 62.2%, P = 0.047). The 2-year RFS rate of group B was markedly superior to that of group D (64.3% vs 23.5%, P = 0.002). Results from multivariate analyses showed that pre-LT DEB-TACE [hazard ratio (HR) = 2.73, 95% confidence interval (CI): 1.44-5.14, P = 0.04], overall target tumor diameter ≤ 7 cm (HR = 1.98, 95%CI: 1.05-3.75, P = 0.035), and AFP level ≤ 400 ng/mL (HR = 2.34; 95%CI: 1.30-4.19, P = 0.009) were significant risk factors for RFS. Additionally, pre-LT DEB-TACE (HR = 3.15, 95%CI: 1.43-6.96, P = 0.004) was identified as a significant risk factor for OS. CONCLUSION: DEB-TACE is a safe and efficient therapy for advanced-stage HCC and also enhances patient survival after LT.

8.
Front Neurol ; 15: 1416557, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994489

RESUMO

The abuse of nitrous oxide (N2O) poses a substantial public health challenge. In many countries, including China, regulations governing the utilization and accessibility to N2O remain ambiguous, particularly within the food industry. Here, we report a case of a 21-year-old female who presented with symptoms of subacute combined degeneration (SCD) of the spinal cord due to N2O abuse. The patient exhibited bilateral lower limb numbness and weakness, low serum vitamin B12 levels with elevated homocysteine levels, and lumbar spine magnetic resonance imaging (MRI) revealed abnormal signals of the spinal cord. Following cessation of N2O and comprehensive therapy including methylcobalamin and nerve growth factor, the symptoms significantly improved. A follow-up examination 3 months later showed good progress in gait stability. At a 5-year follow-up, the patient's previous clinical symptoms had completely disappeared, and her quality of life had returned to normal. This case underscores the urgency of raising awareness and prevention of N2O abuse, emphasizing the importance of timely diagnosis and comprehensive treatment for patient recovery. Clear formulation and enforcement of relevant regulatory measures are equally crucial in reducing instances of abuse.

9.
Artigo em Inglês | MEDLINE | ID: mdl-39042333

RESUMO

PURPOSE: PSMA/PET has been increasingly used to detect PCa, and PSMA/PET-guided biopsy has shown promising results. However, it cannot be confirmed immediately whether the tissues are the targeted area. In this study, we aimed to develop a novel probe, [123I]I-PSMA-7. First, we hope that [123I]I-PSMA-7 can provide instant confirmation for prostate biopsy. Second, we hope it will help detect PCa. METHODS: We synthesized a high-affinity probe, [123I]I-PSMA-7, and evaluated its properties. We included ten patients with suspected PCa and divided them into two groups. The injection and biopsy were approximately 24 h apart. The activity in biopsy lesions was measured as the cpm by a γ-counter. Moreover, we enrolled 3 patients to evaluate the potential of [123I]I-PSMA-7 for detecting PCa. RESULTS: Animal experiments verified the safety, targeting and effectiveness of [123I]I-PSMA-7, and the tumor-to-muscle ratio was greatest at 24 h, which confirmed the results of this study in humans. After injection of 185MBq [123I]I-PSMA-7, 18/55 cores were positive, and the cpm was significantly greater (4345 ± 3547 vs. 714 ± 547, P < 0.001), with an AUC of 0.97 and a cutoff of 1312 (sens/spec of 94.40%/91.90%). At a lower dose, 10/55 biopsy cores were cancerous, and the cpm was 2446 ± 1622 vs. 153 ± 112 (P < 0.001). The AUC was 1, with a cutoff value of 490 (sens/spec of 100%). When the radiopharmaceuticals were added to 370 MBq, we achieved better SPECT/CT imaging. CONCLUSION: With the aid of [123I]I-PSMA-7 and via cpm-based biopsy, we can reduce the number of biopsies to a minimum operation. [123I]I-PSMA-7 PSMA SPECT/CT can also provide good imaging results. TRIAL REGISTRATION: Chinese Clinical trial registry ChiCTR2300069745, Registered 24 March 2023.

10.
IEEE J Biomed Health Inform ; 28(10): 6117-6129, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38905094

RESUMO

Universal lesion detection (ULD) has great value in clinical practice as it can detect various lesions across multiple organs. Deep learning-based detectors have great potential but require high-quality annotated training data. In practice, due to cost, expertise requirements, and the diverse nature of lesions, incomplete annotations are encountered. Directly training ULD detectors under this condition can yield suboptimal results. Leading pseudo-label methods rely on a dynamic lesion-mining mechanism operating at the mini-batch level to address this issue. However, the quality of mined lesions is inconsistent across different iterations, potentially limiting performance enhancement. Inspired by the observation that deep models learn concepts with increasing complexity, we propose an exploratory-training-based ULD (ET-ULD) method to assess the reliability of mined lesions over time. Our approach uses a teacher-student detection model where the teacher mines suspicious lesions, which are then combined with incomplete annotations to train the student. On top of that, we design a bounding-box bank to record the mining timestamps. Each image is trained in several rounds, allowing us to get a sequence of timestamps for the mined lesions. If a mined lesion consistently appears, it is likely to be a true lesion, otherwise, it may just be a noise. This serves as a crucial criterion for selecting reliable mined lesions for retraining. Experimental results show that ET-ULD surpass existing state-of-the-art methods on two distinct lesion image datasets. Notably, on the DeepLesion dataset, ET-ULD achieved a 5.4% improvement in Average Precision (AP) over the previous methods, demonstrating its superior performance.


Assuntos
Mineração de Dados , Aprendizado Profundo , Interpretação de Imagem Assistida por Computador , Humanos , Mineração de Dados/métodos , Interpretação de Imagem Assistida por Computador/métodos , Algoritmos
11.
Int J Pharm ; 658: 124208, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38723731

RESUMO

Pseudomonas aeruginosa (PA), a predominant pathogen in lung infections, poses significant challenges due to its biofilm formation, which is the primary cause of chronic and recalcitrant pulmonary infections. Bacteria within these biofilms exhibit heightened resistance to antibiotics compared to their planktonic counterparts, and their secreted toxins exacerbate lung infections. Diverging from traditional antibacterial therapy for biofilm eradication, this study introduces a novel dry powder inhalation containing muco-inert ciprofloxacin and colistin co-encapsulated liposomes (Cipro-Col-Lips) prepared using ultrasonic spray freeze drying (USFD) technique. This USFD dry powder is designed to efficiently deliver muco-inert Cipro-Col-Lips to the lungs. Once deposited, the liposomes rapidly diffuse into the airway mucus, reaching the biofilm sites. The muco-inert Cipro-Col-Lips neutralize the biofilm-secreted toxins and simultaneously trigger the release of their therapeutic payload, exerting a synergistic antibiofilm effect. Our results demonstrated that the optimal USFD liposomal dry powder formulation exhibited satisfactory in vitro aerosol performance in terms of fine particle fraction (FPF) of 44.44 ± 0.78 %, mass median aerodynamic diameter (MMAD) of 4.27 ± 0.21 µm, and emitted dose (ED) of 99.31 ± 3.31 %. The muco-inert Cipro-Col-Lips effectively penetrate the airway mucus and accumulate at the biofilm site, neutralizing toxins and safeguarding lung cells. The triggered release of ciprofloxacin and colistin works synergistically to reduce the biofilm's antibiotic resistance, impede the development of antibiotic resistance, and eliminate 99.99 % of biofilm-embedded bacteria, including persister bacteria. Using a PA-beads induced biofilm-associated lung infection mouse model, the in vivo efficacy of this liposomal dry powder aerosol was tested, and the results demonstrated that this liposomal dry powder aerosol achieved a 99.7 % reduction in bacterial colonization, and significantly mitigated inflammation and pulmonary fibrosis. The USFD dry powder inhalation containing muco-inert Cipro-Col-Lips emerges as a promising therapeutic strategy for treating PA biofilm-associated lung infections.


Assuntos
Antibacterianos , Biofilmes , Ciprofloxacina , Colistina , Inaladores de Pó Seco , Lipossomos , Infecções por Pseudomonas , Pseudomonas aeruginosa , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Biofilmes/efeitos dos fármacos , Colistina/administração & dosagem , Colistina/farmacologia , Administração por Inalação , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Infecções por Pseudomonas/tratamento farmacológico , Camundongos , Aerossóis , Pulmão/microbiologia , Pulmão/efeitos dos fármacos , Pós , Feminino , Tamanho da Partícula
12.
Sci Rep ; 14(1): 11860, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789583

RESUMO

Acute lung injury (ALI) is life-threatening. MicroRNAs (miRNAs) are often abnormally expressed in inflammatory diseases and are closely associated with ALI. This study investigates whether miRNA-206-3p attenuates pyroptosis in ALI and elucidates the underlying molecular mechanisms. ALI mouse and cell models were established through lipopolysaccharide (LPS) treatment for 24 h. Subsequently, the models were evaluated based on ultrasonography, the lung tissue wet/dry (W/D) ratio, pathological section assessment, electron microscopy, and western blotting. Pyroptosis in RAW264.7 cells was then assessed via electron microscopy, immunofluorescence, and western blotting. Additionally, the regulatory relationship between miRNA-206-3p and the Toll-like receptor (TLR)4/nuclear factor (NF)-κB/Nod-like receptor protein-3 (NLRP3) pathway was verified. Finally, luciferase reporter gene and RNA pull-down assays were used to verify the targeting relationship between miRNA-206-3p and TLR4. miRNA206-3p levels are significantly decreased in the LPS-induced ALI model. Overexpression of miRNA-206-3p improves ALI, manifested as improved lung ultrasound, improved pathological changes of lung tissue, reduced W/D ratio of lung tissue, release of inflammatory factors in lung tissue, and reduced pyroptosis. Furthermore, overexpression of miRNA-206-3p contributed to reversing the ALI-promoting effect of LPS by hindering TLR4, myeloid differentiation primary response 88 (MyD88), NF-κB, and NLRP3 expression. In fact, miRNA-206-3p binds directly to TLR4. In conclusion, miRNA-206-3p alleviates LPS-induced ALI by inhibiting inflammation and pyroptosis via TLR4/NF-κB/NLRP3 pathway modulation.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , MicroRNAs , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Masculino , Camundongos , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Modelos Animais de Doenças , Inflamação/metabolismo , Inflamação/patologia , Inflamação/genética , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Piroptose/genética , Células RAW 264.7 , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Camundongos Endogâmicos BALB C
14.
Org Lett ; 26(15): 3086-3090, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38591933

RESUMO

An organocatalytic enantioselective alkylation of α,α-disubstituted aldehydes with 3-bromooxindoles is reported. Enantioenriched oxindoles with vicinal quaternary stereocenters are accessed by an asymmetric conjugate addition process of branched aldehydes with o-azaxylylene intermediates (indol-2-ones). Key to the success of highly diastereo- and enantioselective transformations is the combined use of a triphenylsilyl-protected ß-amino alcohol catalyst derived from the spiropyrrolidine scaffold and 3,5-dinitrobenzoic acid. This study also presents a rare example of aldehyde alkylation with the formation of consecutive quaternary stereocenters.

15.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38441429

RESUMO

Superconducting magnets are widely used in nuclear fusion reactors, high-energy particle accelerators, steady-state high magnetic fields, etc. Higher magnetic fields and higher operating temperatures are two application trends. High temperature superconducting (HTS) materials are the only choice for high temperature and high field magnets in the future. The first- and second-generation HTS materials have a typical tape structure; their critical performance is magnetic field angle and temperature dependent. A new test facility is developed for an experimental study on the an-isotropic critical current. The field angle can be changed from 0° to 360° with a resolution of 1°. The rotation deviation angle is measured to be 0.2° when the upper part rotates 90°. The temperature can be changed from 4.2 to 80 K. The temperature errors are ±50, ±80, and ±135 mK for 4.2-20, 20-40, and 40-80 K, respectively. The angle dependence of critical current (Ic) of the tested rare-earth barium copper oxide tape within 0°-30° is strong. From 30° to 90°, the sample Ic almost does not change with the magnetic field angle. The implementation of the project will not only promote the structural optimization of HTS tapes but also promote the miniaturization and economical application of HTS magnets.

16.
J Hazard Mater ; 466: 133587, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280329

RESUMO

Microplastics (MPs) have been shown to adsorb heavy metals and serve as vehicles for their environmental transport. To date, insufficient studies have focused on enterohepatic injury in mice co-exposed to both MPs and cadmium (Cd). Here, we report that Cd adsorption increased the surface roughness and decreased the monodispersity of PS-MPs. Furthermore, exposure to both PS-MPs and Cd resulted in a more severe toxic effect compared to single exposure, with decreased body weight gain, shortened colon length, and increased colonic and hepatic inflammatory response observed. This can be attributed to an elevated accumulation of Cd resulting from increased gut permeability, coupled with the superimposed effects of oxidative stress. In addition, using 16 S sequencing and fecal microbiota transplantation, it was demonstrated that gut microbiota dysbiosis plays an essential role in the synergistic toxicity induced by PS-MPs and Cd in mice. This study showed that combined exposure to MPs and Cd induced more severe intestinal and liver damage in mice compared to individual exposure, and provided a new perspective for a more systematic risk assessment process related to MPs exposure.


Assuntos
Cádmio , Metais Pesados , Animais , Camundongos , Cádmio/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Metais Pesados/toxicidade , Estresse Oxidativo , Poliestirenos/farmacologia
17.
IEEE Trans Pattern Anal Mach Intell ; 46(6): 4398-4409, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38236681

RESUMO

Label-noise learning (LNL) aims to increase the model's generalization given training data with noisy labels. To facilitate practical LNL algorithms, researchers have proposed different label noise types, ranging from class-conditional to instance-dependent noises. In this paper, we introduce a novel label noise type called BadLabel, which can significantly degrade the performance of existing LNL algorithms by a large margin. BadLabel is crafted based on the label-flipping attack against standard classification, where specific samples are selected and their labels are flipped to other labels so that the loss values of clean and noisy labels become indistinguishable. To address the challenge posed by BadLabel, we further propose a robust LNL method that perturbs the labels in an adversarial manner at each epoch to make the loss values of clean and noisy labels again distinguishable. Once we select a small set of (mostly) clean labeled data, we can apply the techniques of semi-supervised learning to train the model accurately. Empirically, our experimental results demonstrate that existing LNL algorithms are vulnerable to the newly introduced BadLabel noise type, while our proposed robust LNL method can effectively improve the generalization performance of the model under various types of label noise. The new dataset of noisy labels and the source codes of robust LNL algorithms are available at https://github.com/zjfheart/BadLabels.

18.
Adv Healthc Mater ; 13(9): e2303200, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38183410

RESUMO

Narrow photo-absorption range and low carrier utilization are significant barriers that restrict the antitumor efficiency of 2D bismuth oxyhalide (BiOX, X = Cl, Br, I) nanosheets (NSs). Introducing oxygen vacancy (OV) defects can expand the absorption range and improve carrier utilization, which are crucial but also challenging. In this study, a series of BiOxCl NSs with different OV defect concentrations (x = 1, 0.7, 0.5) is developed, which shows full spectrum absorption and strong absorption in the second near-infrared region (NIR-II). Density functional theory calculations are utilized to calculate the crystal structure and density states of BiOxCl, which confirm that part of the carriers is separated by OV enhanced internal electric field to improve carrier utilization. The carriers without redox reaction can be trapped in the OV, leading to great majority of photo-generated carriers promoting the photothermal performance. Triggered by single NIR-II (1064 nm), BiOxCl NSs' bidirectional efficient utilization of carriers achieves synchronously combined phototherapy, leading to enhanced tumor ablation and multimodal diagnostic in vitro and vivo. It is thus believed that this work provides an innovative strategy to design and construct nanoplatforms of indirect band gap semiconductors for clinical phototheranostics.


Assuntos
Nanopartículas , Neoplasias , Humanos , Oxigênio/química , Fototerapia/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Imagem Multimodal , Nanopartículas/química , Nanomedicina Teranóstica/métodos , Linhagem Celular Tumoral
19.
Quant Imaging Med Surg ; 14(1): 604-617, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223061

RESUMO

Background: The incidence of gallbladder adenocarcinoma (GBA) is relatively low, yet it exhibits a high degree of malignancy and a significantly low 5-year survival rate. The aim of this study was to investigate the prognostic value of pretreatment 2-[18F]fluoro-D-glucose positron emission tomography {2-[18F]FDG PET} parameters in predicting outcomes for patients with GBA. Methods: In total, 67 patients with GBA who underwent 2-[18F]FDG PET/computed tomography (CT) before treatment were retrospectively analyzed at Chinese PLA General Hospital from January 2012 to June 2022. All patients were diagnosed by pathology, and their baseline characteristics and clinical data were collected. The metabolic PET parameters of the primary and metastatic lesions were measured, including the maximum and average standardized uptake values (SUVs), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). The prognostic significance of metabolic parameters and other clinical variables was assessed using Cox proportional hazards regression models. Differences in progression-free survival (PFS) and overall survival (OS) in relation to metabolic parameters were examined using the Kaplan-Meier method. Results: During a median follow-up period of 14.2 months, 43 patients (64.2%) experienced tumor recurrence or progression, and 38 patients (56.7%) died of cancer. In the univariate Cox regression analysis, liver parenchymal invasion (P=0.001), lymph node metastasis (P=0.007), distant metastases (P=0.049), tumor differentiation (P=0.028), surgery (P=0.014), carcinoembryonic antigen (CEA) level (P=0.030), carbohydrate antigen 19-9 (CA19-9) level (P=0.003), TLG (P=0.005), MTV (P<0.001), sum of the TLGs of the primary and metastatic lesions (total TLG, tTLG) (P=0.001), and sum of the MTVs of the primary and metastatic lesions (total MTV, tMTV) (P<0.001) were significant predictors of PFS. In multivariate analysis, MTV was an independent predictor of PFS [hazard ratio (HR) =2.785; 95% confidence interval (CI): 1.204-6.441; P=0.017]. In the univariate Cox regression analysis, liver parenchymal invasion (P=0.001), lymph node metastasis (P=0.027), distant metastases (P=0.036), tumor differentiation (P=0.047), surgery (P=0.002), neutrophil-to-lymphocyte ratio (NLR) (P=0.011), CEA level (P=0.036), CA19-9 level (P<0.001), TLG (P=0.007), MTV (P<0.001), tTLG (P=0.003), and tMTV (P<0.001) were significant predictors of OS. In the multivariate analysis, higher CA19-9 levels >37 U/mL and a greater tMTV (HR =2.961; 95% CI: 1.092-8.024; P=0.033) were predictive of OS. Conclusions: Our study results suggest that pretreatment 2-[18F]FDG PET parameters can not only assist in the diagnosis of patients with GBA but may also serve as predictive factors for the prognosis of these patients and should thus be applied in their treatment.

20.
PeerJ ; 12: e16807, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250731

RESUMO

Background: The objective of this study was to investigate the prognostic significance of total metabolic tumor volume (TMTV) derived from baseline 18F-2-fluoro-2-deoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT), in conjunction with epidermal growth factor receptor (EGFR) mutation status, among patients with lung adenocarcinoma (LUAD). Methods: We performed a retrospective analysis on 141 patients with LUAD (74 males, 67 females, median age 67 (range 34-86)) who underwent 18F-FDG PET/CT and had their EGFR mutation status determined. Optimal cutoff points for TMTV were determined using time-dependent receiver operating characteristic curve analysis. The survival difference was compared using Cox regression analysis and Kaplan‒Meier curves. Results: The EGFR mutant patients (n = 79, 56.0%) exhibited significantly higher 2-year progression-free survival (PFS) and overall survival (OS) rates compared to those with EGFR wild-type (n = 62, 44.0%), with rates of 74.2% vs 69.2% (P = 0.029) and 86.1% vs 67.7% (P = 0.009), respectively. The optimal cutoff values of TMTV were 36.42 cm3 for PFS and 37.51 cm3 for OS. Patients with high TMTV exhibited significantly inferior 2-year PFS and OS, with rates of 22.4% and 38.1%, respectively, compared to those with low TMTV, who had rates of 85.8% and 95.0% (both P < 0.001). In both the EGFR mutant and wild-type groups, patients exhibiting high TMTV demonstrated significantly inferior 2-year PFS and OS compared to those with low TMTV. In multivariate analysis, EGFR mutation status (hazard ratio, HR, 0.41, 95% confidence interval, CI [0.18-0.94], P = 0.034) and TMTV (HR 8.08, 95% CI [2.34-28.0], P < 0.001) were independent prognostic factors of OS, whereas TMTV was also an independent prognosticator of PFS (HR 2.59, 95% CI [1.30-5.13], P = 0.007). Conclusion: Our study demonstrates that the integration of TMTV on baseline 18F-FDG PET/CT with EGFR mutation status improves the accuracy of prognostic evaluation for patients with LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Idoso , Feminino , Humanos , Masculino , Adenocarcinoma de Pulmão/diagnóstico por imagem , Receptores ErbB/genética , Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Mutação , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Estudos Retrospectivos , Carga Tumoral , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
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