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1.
Med Image Anal ; 97: 103285, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39116766

RESUMO

We introduce the largest abdominal CT dataset (termed AbdomenAtlas) of 20,460 three-dimensional CT volumes sourced from 112 hospitals across diverse populations, geographies, and facilities. AbdomenAtlas provides 673 K high-quality masks of anatomical structures in the abdominal region annotated by a team of 10 radiologists with the help of AI algorithms. We start by having expert radiologists manually annotate 22 anatomical structures in 5,246 CT volumes. Following this, a semi-automatic annotation procedure is performed for the remaining CT volumes, where radiologists revise the annotations predicted by AI, and in turn, AI improves its predictions by learning from revised annotations. Such a large-scale, detailed-annotated, and multi-center dataset is needed for two reasons. Firstly, AbdomenAtlas provides important resources for AI development at scale, branded as large pre-trained models, which can alleviate the annotation workload of expert radiologists to transfer to broader clinical applications. Secondly, AbdomenAtlas establishes a large-scale benchmark for evaluating AI algorithms-the more data we use to test the algorithms, the better we can guarantee reliable performance in complex clinical scenarios. An ISBI & MICCAI challenge named BodyMaps: Towards 3D Atlas of Human Body was launched using a subset of our AbdomenAtlas, aiming to stimulate AI innovation and to benchmark segmentation accuracy, inference efficiency, and domain generalizability. We hope our AbdomenAtlas can set the stage for larger-scale clinical trials and offer exceptional opportunities to practitioners in the medical imaging community. Codes, models, and datasets are available at https://www.zongweiz.com/dataset.


Assuntos
Algoritmos , Benchmarking , Imageamento Tridimensional , Radiografia Abdominal , Tomografia Computadorizada por Raios X , Humanos , Imageamento Tridimensional/métodos , Conjuntos de Dados como Assunto
3.
J Thorac Dis ; 16(6): 3909-3922, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38983179

RESUMO

Background: Immunochemotherapy was an emerging neoadjuvant treatment mode that can potentially benefit patients with esophageal carcinoma, but its synergistic mechanism and impact on the tumor immune microenvironment were still unclear. The purpose of this study was to investigate the outcomes of neoadjuvant chemotherapy (nCT) and neoadjuvant immunochemotherapy (nICT) in tumor microenvironment (TME) remodeling among patients with esophageal squamous cell carcinoma (ESCC) and to evaluate the prognostic value of immune-related biomarkers and clinicopathological characteristics. Methods: Patients with locally advanced ESCC who underwent neoadjuvant therapy followed by esophagectomy at the Fourth Hospital of Hebei Medical University between December 2019 and March 2022 were enrolled in this retrospective study. We examined TME features and immune antigen-related biomarkers before and after neoadjuvant therapy. Logistic and Cox regression model were used to evaluate the correlation between these factors and other clinical features and outcomes. Results: A total of 50 eligible participants were analyzed, including 31 males (62%), 25 patients of ≥65 years old, 4/28/18 of upper/middle/lower thoracic cancer, 25/17/8 of poor/moderate/high tumor differentiation, 8/42 of cT1+2/T3+4 stages and 30/20 of cN0/N+ stages. In the entire cohort, the rates of pathological complete response (pCR) and major pathological response (MPR) were 18% and 30%, respectively. pCR rates were 7.1% and 22.2% (χ2=0.699; P=0.40) MPR rates were 7.1% and 38.9% (χ2=4.837; P=0.03) in the nCT and nICT groups, respectively. Compared with the non-pCR patients, the pCR patients had a higher baseline programmed cell death ligand-1 (PD-L1) tumor proportion score (TPS) positive expression rate (16.7% vs. 77.8%, χ2=13.089; P<0.001). Following neoadjuvant therapy, the expression rates of PD-L1, CD3+ T cells, and CD8+ T cells in the tumor tissue was higher in the nICT group compared to the nCT group (P<0.05). Deficient expression of mismatch repair (MMR) genes was only observed in one patient (2%). Among patient-related biomarkers, lymphocyte and neutrophil counts decreased after treatment, with no significant changes in the neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio (PLR). Cox regression analysis showed that pretreatment, well-differentiated tumors and positive PD-L1 status were positive predictors of MPR (P<0.05). MPR was an independent predictor of disease-free survival (DFS) (P=0.03). Conclusions: Compared to nCT, nICT could more significantly upregulates PD-L1 TPS, PD-L1 combined positive score (CPS), CD3+ T cells, and CD8+ T cells. Pretreatment tumor differentiation and PD-L1 TPS level could be predictive of MPR. Our findings suggested that the combination of chemotherapy and immunotherapy may be more beneficial for activating anti-tumor immunity in the TME.

4.
BMC Med ; 22(1): 310, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075419

RESUMO

BACKGROUND: Uterine corpus endometrial carcinoma (UCEC) is a prevalent gynecologic malignancy with a favorable prognosis if detected early. However, there is a lack of accurate and reliable early detection tests for UCEC. This study aims to develop a precise and non-invasive diagnostic method for UCEC using circulating cell-free DNA (cfDNA) fragmentomics. METHODS: Peripheral blood samples were collected from all participants, and cfDNA was extracted for analysis. Low-coverage whole-genome sequencing was performed to obtain cfDNA fragmentomics data. A robust machine learning model was developed using these features to differentiate between UCEC and healthy conditions. RESULTS: The cfDNA fragmentomics-based model showed high predictive power for UCEC detection in training (n = 133; AUC 0.991) and validation cohorts (n = 89; AUC 0.994). The model manifested a specificity of 95.5% and a sensitivity of 98.5% in the training cohort, and a specificity of 95.5% and a sensitivity of 97.8% in the validation cohort. Physiological variables and preanalytical procedures had no significant impact on the classifier's outcomes. In terms of clinical benefit, our model would identify 99% of Chinese UCEC patients at stage I, compared to 21% under standard care, potentially raising the 5-year survival rate from 84 to 95%. CONCLUSION: This study presents a novel approach for the early detection of UCEC using cfDNA fragmentomics and machine learning showing promising sensitivity and specificity. Using this model in clinical practice could significantly improve UCEC management and control, enabling early intervention and better patient outcomes. Further optimization and validation of this approach are warranted to establish its clinical utility.


Assuntos
Ácidos Nucleicos Livres , Detecção Precoce de Câncer , Neoplasias do Endométrio , Humanos , Feminino , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/genética , Pessoa de Meia-Idade , Ácidos Nucleicos Livres/sangue , Detecção Precoce de Câncer/métodos , Idoso , Aprendizado de Máquina , Adulto , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Sensibilidade e Especificidade
5.
Childs Nerv Syst ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985317

RESUMO

PURPOSE: This article aims to analyze pediatric meningioma's imaging characteristics, especially those in unusual locations. METHODS: Pediatric patients with pathologically confirmed meningiomas at our hospital from January 2010 to January 2024 were enrolled. Meningiomas located in the cerebral convexity, parasagittal falcine region, anterior skull base, middle skull base, sphenoid ridge, cerebellopontine angle (CPA), olfactory groove, or juxtasella were considered in usual locations. Meningiomas found in other areas were considered in unusual locations. Clinical information, pathology results, and imaging features of pediatric meningiomas in usual and usual locations were analyzed and compared. RESULTS: A total of 18 patients (19 meningiomas) were enrolled, including 14 males and 4 females, with an average age of 14 years (ranging from 6 to 18 years). A total of 12 (63.2%) meningiomas were in the unusual location, including four (33.3%) were intraparenchymal, four (33.3%) were intraventricular, two (16.7%) were intraosseous, one (8.3%) case was in the paranasal sinus, and one (8.3%) was intraspinal. The meningiomas in unusual locations usually lacked the meningeal tail sign, and the misdiagnosis rate on preoperative imaging was significantly higher than that of meningiomas in usual locations. CONCLUSION: Pediatric meningiomas are prone to occur in unusual locations. When they occur in usual locations, they often lack typical radiographic features of meningiomas, leading to potential misdiagnosis before surgery. Recognition of the imaging characteristics of meningiomas in unusual locations in children may facilitate accurate preoperative imaging diagnosis.

6.
PeerJ ; 12: e17628, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952983

RESUMO

Background: Ovarian cancer is an aggressive malignancy with high mortality known for its considerable metastatic potential. This study aimed to explore the expression and functional role of Unc-51 like autophagy activating kinase 2 (ULK2) in the progression of ovarian cancer. Methods: ULK2 expression patterns in ovarian cancer tissues as well as benign tumor control samples obtained from our institution were evaluated using immunohistochemistry. Cell counting kit 8 and Transwell assays were applied to assess the effects of ULK2 overexpression on cell proliferation, migration and invasion, respectively. RNA sequencing was performed to explore potential mechanisms of action of ULK2 beyond its classical autophagy modulation. Results: Our experiments showed significant downregulation of ULK2 in ovarian cancer tissues. Importantly, low expression of ULK2 was markedly correlated with decreased overall survival. In vitro functional studies further demonstrated that overexpression of ULK2 significantly suppressed tumor cell proliferation, migration, and invasion. RNA sequencing analysis revealed a potential regulatory role of ULK2 in the insulin signaling pathway through upregulation of insulin-like growth factor binding protein-3 (IGFBP3) in ovarian cancer cells. Conclusions: In summary, the collective data indicated that ULK2 acted as a tumor suppressor in ovarian cancer by upregulating the expression of IGFBP3. Our study underscores the potential utility of ULK2 as a valuable prognostic marker for ovarian cancer.


Assuntos
Movimento Celular , Proliferação de Células , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Invasividade Neoplásica , Neoplasias Ovarianas , Humanos , Feminino , Movimento Celular/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Linhagem Celular Tumoral , Invasividade Neoplásica/genética , Proliferação de Células/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Regulação Neoplásica da Expressão Gênica , Regulação para Cima , Transdução de Sinais , Proteínas Serina-Treonina Quinases
7.
J Hazard Mater ; 475: 134911, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38889457

RESUMO

1-Nitropyrene (1-NP) is a neurodevelopmental toxicant. This study was to evaluate the impact of exposure to 1-NP after weaning on anxiety-like behavior. Five-week-old mice were administered with 1-NP (0.1 or 1 mg/kg) daily for 4 weeks. Anxiety-like behaviour was measured using elevated-plus maze (EPM) and open field test (OFT). In EPM test, time spending in open arm and times entering open arm were reduced in 1-NP-treated mice. In OFT test, time spent in the center region and times entering the center region were diminished in 1-NP-treated mice. Prefrontal dendritic length and number of dendrite branches were decreased in 1-NP-treated mice. Prefrontal PSD95, an excitatory postsynaptic membrane protein, and gephyrin, an inhibitory postsynaptic membrane protein, were downregulated in 1-NP-treated mice. Further analysis showed that peripheral steroid hormones, including serum testosterone (T) and estradiol (E2), testicular T, and ovarian E2, were decreased in 1-NP-treated mice. Interestingly, T and E2 were diminished in 1-NP-treated prefrontal cortex. Prefrontal T and E2 synthases were diminished in 1-NP-treated mice. Mechanistically, GCN2-eIF2α, a critical pathway that regulates ribosomal protein translation, was activated in 1-NP-treated prefrontal cortex. These results indicate that exposure to 1-NP after weaning induces anxiety-like behaviour partially by inhibiting steroid hormone synthesis in prefrontal cortex.


Assuntos
Ansiedade , Córtex Pré-Frontal , Pirenos , Desmame , Animais , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ansiedade/induzido quimicamente , Masculino , Pirenos/toxicidade , Feminino , Camundongos , Comportamento Animal/efeitos dos fármacos , Testosterona/sangue , Estradiol
8.
BMC Cancer ; 24(1): 679, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38831450

RESUMO

OBJECTIVE: To evaluate the feasibility, safety and efficacy of concurrent simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) combined with nimotuzumab in the treatment of locally advanced esophageal squamous cell cancer (ESCC). METHODS: Eligible patients were histologically proven to have locally advanced ESCC, and were unable to tolerate or refuse concurrent chemoradiotherapy (CCRT). Enrolled patients underwent concurrent SIB-IMRT in combination with nimotuzumab. SIB-IMRT: For the planning target volume of clinical target volume (PTV-C), the prescription dose was 50.4 Gy/28fractions, 1.8 Gy/fraction, 5fractions/week, concurrently, the planning target volume of gross tumor (PTV-G) undergone an integrated boost therapy, with a prescription dose of 63 Gy/28fractions, 2.25 Gy/fraction, 5 fractions/week. Nimotuzumab was administered concurrently with radiotherapy, 200 mg/time, on D1, 8, 15, 22, 29, and 36, with a total accumulation of 1200 mg through intravenous infusion. The primary endpoint of the study was the safety and efficacy of the combined treatment regimen, and the secondary endpoints were 1-year, 2-year, and 3-year local control and survival outcomes. RESULTS: (1) From December 2018 to August 2021, 35 patients with stage II-IVA ESCC were enrolled and 34 patients completed the full course of radiotherapy and the intravenous infusion of full-dose nimotuzumab. The overall completion rate of the protocol was 97.1%. (2) No grade 4-5 adverse events occurred in the entire group. The most common treatment-related toxicity was acute radiation esophagitis, with a total incidence of 68.6% (24/35). The incidence of grade 2 and 3 acute esophagitis was 25.7% (9/35) and 17.1% (6/35), respectively. The incidence of acute radiation pneumonitis was 8.6% (3/35), including one case each of Grades 1, 2, and 3 pneumonitis. Adverse events in other systems included decreased blood cells, hypoalbuminemia, electrolyte disturbances, and skin rash. Among these patients, five experienced grade 3 electrolyte disturbances during the treatment period (three with grade 3 hyponatremia and two with grade 3 hypokalemia). (3) Efficacy: The overall CR rate was 22.8%, PR rate was 71.4%, ORR rate was 94.2%, and DCR rate was 97.1%.(4) Local control and survival: The 1-, 2-, and 3-year local control (LC) rate, progression-free survival(PFS) rate, and overall survival(OS) rate for the entire group were 85.5%, 75.4%, and 64.9%; 65.7%, 54.1%, and 49.6%; and 77.1%, 62.9%, and 54.5%, respectively. CONCLUSIONS: The combination of SIB-IMRT and nimotuzumab for locally advanced esophageal cancer demonstrated good feasibility, safety and efficacy. It offered potential benefits in local control and survival. Acute radiation esophagitis was the primary treatment-related toxicity, which is clinically manageable. This comprehensive treatment approach is worthy of further clinical exploration (ChiCTR1900027936).


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Radioterapia de Intensidade Modulada , Humanos , Masculino , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Feminino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/tratamento farmacológico , Idoso , Quimiorradioterapia/métodos , Adulto , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/administração & dosagem , Resultado do Tratamento
9.
NPJ Precis Oncol ; 8(1): 99, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831114

RESUMO

Fetal adenocarcinoma of the lung (FLAC) is a rare form of lung adenocarcinoma and was divided into high-grade (H-FLAC) and low-grade (L-FLAC) subtypes. Despite the existence of some small case series studies, a comprehensive multi-omics study of FLAC has yet to be undertaken. In this study, we depicted the multi-omics landscapes of this rare lung cancer type by performing multi-regional sampling on 20 FLAC cases. A comparison of multi-omics profiles revealed significant differences between H-FLAC and L-FLAC in a multi-omic landscape. Two subtypes also showed distinct relationships between multi-layer intratumor heterogeneity (ITH). We discovered that a lower genetic ITH was significantly associated with worse recurrence-free survival and overall survival in FLAC patients, whereas higher methylation ITH in H-FLAC patients suggested a short survival. Our findings highlight the complex interplay between genetic and transcriptional heterogeneity in FLAC and suggest that different types of ITH may have distinct implications for patient prognosis.

10.
Med Image Anal ; 97: 103226, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38852215

RESUMO

The advancement of artificial intelligence (AI) for organ segmentation and tumor detection is propelled by the growing availability of computed tomography (CT) datasets with detailed, per-voxel annotations. However, these AI models often struggle with flexibility for partially annotated datasets and extensibility for new classes due to limitations in the one-hot encoding, architectural design, and learning scheme. To overcome these limitations, we propose a universal, extensible framework enabling a single model, termed Universal Model, to deal with multiple public datasets and adapt to new classes (e.g., organs/tumors). Firstly, we introduce a novel language-driven parameter generator that leverages language embeddings from large language models, enriching semantic encoding compared with one-hot encoding. Secondly, the conventional output layers are replaced with lightweight, class-specific heads, allowing Universal Model to simultaneously segment 25 organs and six types of tumors and ease the addition of new classes. We train our Universal Model on 3410 CT volumes assembled from 14 publicly available datasets and then test it on 6173 CT volumes from four external datasets. Universal Model achieves first place on six CT tasks in the Medical Segmentation Decathlon (MSD) public leaderboard and leading performance on the Beyond The Cranial Vault (BTCV) dataset. In summary, Universal Model exhibits remarkable computational efficiency (6× faster than other dataset-specific models), demonstrates strong generalization across different hospitals, transfers well to numerous downstream tasks, and more importantly, facilitates the extensibility to new classes while alleviating the catastrophic forgetting of previously learned classes. Codes, models, and datasets are available at https://github.com/ljwztc/CLIP-Driven-Universal-Model.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Radiografia Abdominal/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Inteligência Artificial
11.
Adv Sci (Weinh) ; 11(28): e2306294, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757379

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, characterized by social communication disability and stereotypic behavior. This study aims to investigate the impact of prenatal exposure to 1-nitropyrene (1-NP), a key component of motor vehicle exhaust, on autism-like behaviors in a mouse model. Three-chamber test finds that prenatal 1-NP exposure causes autism-like behaviors during the weaning period. Patch clamp shows that inhibitory synaptic transmission is reduced in medial prefrontal cortex of 1-NP-exposed weaning pups. Immunofluorescence finds that prenatal 1-NP exposure reduces the number of prefrontal glutamate decarboxylase 67 (GAD67) positive interneurons in fetuses and weaning pups. Moreover, prenatal 1-NP exposure retards tangential migration of GAD67-positive interneurons and downregulates interneuron migration-related genes, such as Nrg1, Erbb4, and Sema3F, in fetal forebrain. Mechanistically, prenatal 1-NP exposure reduces hydroxymethylation of interneuron migration-related genes through inhibiting ten-eleven translocation (TET) activity in fetal forebrain. Supplement with alpha-ketoglutarate (α-KG), a cofactor of TET enzyme, reverses 1-NP-induced hypohydroxymethylation at specific sites of interneuron migration-related genes. Moreover, α-KG supplement alleviates 1-NP-induced migration retardation of interneurons in fetal forebrain. Finally, maternal α-KG supplement improves 1-NP-induced autism-like behaviors in weaning offspring. In conclusion, prenatal 1-NP exposure causes autism-like behavior partially by altering DNA hydroxymethylation of interneuron migration-related genes in developing brain.


Assuntos
Encéfalo , Modelos Animais de Doenças , Efeitos Tardios da Exposição Pré-Natal , Animais , Camundongos , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/genética , Feminino , Gravidez , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Transtorno Autístico/genética , Transtorno Autístico/induzido quimicamente , Transtorno Autístico/metabolismo , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Comportamento Animal/efeitos dos fármacos , Masculino , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/metabolismo , Pirenos/toxicidade , Camundongos Endogâmicos C57BL
12.
ACS Biomater Sci Eng ; 10(6): 3568-3598, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38815129

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive subtype with the worst prognosis and highest recurrence rates. The treatment choices are limited due to the scarcity of endocrine and HER2 targets, except for chemotherapy. However, the side effects of chemotherapy restrict its long-term usage. Immunotherapy shows potential as a promising therapeutic strategy, such as inducing immunogenic cell death, immune checkpoint therapy, and immune adjuvant therapy. Nanotechnology offers unique advantages in the field of immunotherapy, such as improved delivery and targeted release of immunotherapeutic agents and enhanced bioavailability of immunomodulators. As well as the potential for combination therapy synergistically enhanced by nanocarriers. Nanoparticles-based combined application of multiple immunotherapies is designed to take the tactics of enhancing immunogenicity and reversing immunosuppression. Moreover, the increasing abundance of biomedical materials holds more promise for the development of this field. This review summarizes the advances in the field of nanoparticle-mediated immunotherapy in terms of both immune strategies for treatment and the development of biomaterials and presents challenges and hopes for the future.


Assuntos
Imunoterapia , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Imunoterapia/métodos , Nanopartículas/uso terapêutico , Nanopartículas/química , Feminino , Animais
13.
Materials (Basel) ; 17(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38673276

RESUMO

Bismuth telluride (Bi2Te3)-based alloys have been extensively employed in energy harvesting and refrigeration applications for decades. However, commercially produced Bi2Te3-based alloys using the zone-melting (ZM) technique often encounter challenges such as insufficient mechanical properties and susceptibility to cracking, particularly in n-type Bi2Te3-based alloys, which severely limit the application scenarios for bismuth telluride devices. In this work, we seek to enhance the mechanical properties of n-type Bi2Te2.7Se0.3 alloys while preserving their thermoelectrical performance by a mixed mechanism of grain refinement and the TiN composite phase-introduced pinning effect. These nanoscale processes, coupled with the addition of TiN, result in a reduction in grain size. The pinning effects of nano-TiN contribute to increased resistance to crack propagation. Finally, the TiN-dispersed Bi2Te2.7Se0.3 samples demonstrate increased hardness, bending strength and compressive strength, reaching 0.98 GPa, 36.3 MPa and 74 MPa. When compared to the ZM ingots, those represent increments of 181%, 60% and 67%, respectively. Moreover, the thermoelectric performance of the TiN-dispersed Bi2Te2.7Se0.3 samples is identical to the ZM ingots. The samples exhibit a peak dimensionless figure of merit (ZT) value of 0.957 at 375 K, with an average ZT value of 0.89 within the 325-450 K temperature range. This work has significantly enhanced mechanical properties, increasing the adaptability and reliability of bismuth telluride devices for various applications, and the multi-effect modulation of mechanical properties demonstrated in this study can be applied to other thermoelectric material systems.

14.
Neuroradiology ; 66(8): 1383-1390, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38678123

RESUMO

PURPOSE: In brain development, Myelination is the characteristic feature of white matter maturation, which plays an important role in efficient information transmitting. The white matter abnormality has been reported to be associated with self-limited epilepsy with centrotemporal spikes (SeLECTS). This study aimed to detect the altered white matter region in the SeLECTS patients by the combination of diffusion tensor imaging (DTI) and quantitative susceptibility mapping (QSM) technique. METHODS: 27 children with SeLECTS and 23 age- and gender-matched healthy children were enrolled. All participants were scanned with 3.0-T MRI to acquire the structure, diffusion and susceptibility-weighted data. The susceptibility and diffusion weighted data were processed to obtain quantitative susceptibility map and fraction anisotropy (FA) map. Then voxel-wise tract-based spatial statistics (TBSS) were used to analyze quantitative susceptibility and FA data. RESULTS: Both DTI and QSM revealed extensive white matter alterations in the frontal, parietal, and temporal lobes in SeLECTS patients. The overlapped region of DTI and QSM analyses was located in the fiber tracts of the corona radiata. The FA values in this overlapped region were negatively correlated with the magnetic susceptibility values. CONCLUSION: Our results suggest that TBSS-based QSM can be employed as a novel approach for characterizing alterations in white matter in SeLECTS. And the combination of QSM and DTI can provide a more comprehensive evaluation of white matter integrity by utilizing different biophysical features.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Feminino , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Criança , Epilepsia Rolândica/diagnóstico por imagem , Epilepsia Rolândica/fisiopatologia , Estudos de Casos e Controles , Anisotropia , Mapeamento Encefálico/métodos , Pré-Escolar , Adolescente
15.
J Mater Chem B ; 12(12): 2938-2949, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38426380

RESUMO

The standard treatment for non-muscle invasive bladder cancer (NMIBC) is transurethral resection of bladder tumor (TURBT). However, this procedure may miss small lesions or incompletely remove them, resulting in cancer recurrence or progression. As a result, intravesical instillation of chemotherapy or immunotherapy drugs is often used as an adjunctive treatment after TURBT to prevent cancer recurrence. In the traditional method, drugs are instilled into the patient's bladder through a urinary catheter under sterile conditions. However, this treatment exposes the bladder mucosa to the drug directly, leading to potential side effects like chemical cystitis. Furthermore, this treatment has several limitations, including a short drug retention period, susceptibility to urine dilution, low drug permeability, lack of targeted effect, and limited long-term clinical efficacy. Hydrogel, a polymer material with a high-water content, possesses solid elasticity and liquid fluidity, making it compatible with tissues and environmentally friendly. It exhibits great potential in various applications. One emerging use of hydrogels is in intravesical instillation. By employing hydrogels, drug dilution is minimized, and drug absorption, retention, and persistence in the bladder are enhanced due to the mucus-adhesive and flotation properties of hydrogel materials. Furthermore, hydrogels can improve drug permeability and offer targeting capabilities. This article critically examines the current applications and future prospects of hydrogels in the treatment of bladder cancer.


Assuntos
Hidrogéis , Neoplasias da Bexiga Urinária , Humanos , Hidrogéis/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Sistemas de Liberação de Medicamentos , Administração Intravesical , Resultado do Tratamento
16.
Opt Express ; 32(2): 1878-1889, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297730

RESUMO

Demand for ultra-small, inexpensive, and high-accurate 3D shape measurement devices is growing rapidly, especially in the industrial and consumer electronics sectors. Phase shifting profilometry (PSP) is a powerful candidate due to its advantages of high accuracy, great resolution, and insensitivity to ambient light. As a key component in PSP, the projector used to generate the phase-shifting sinusoidal fringes must be ultra-small (several millimeters), low-cost, and simple to control. However, existing projection methods make it difficult to meet these requirements simultaneously. In this paper, we present a modern technique that can be used to fabricate the desired projector. A specifically designed device based on segmented liquid crystal display (SLCD) technology is used to display the projected patterns, and a cylindrical lens is used as the projection lens. The SLCD device can display four sets of specific filled binary patterns, each yielding a sinusoidal fringe, and all four sinusoidal fringes satisfy the four-step phase shift relation. 3D shape measurement experiments verify the performance of the projector. Considering that the size of SLCD devices can be reduced to a few millimeters, the proposed technique can be easily used to manufacture ultra-small, low-cost, and simple-to-control PSP projectors.

17.
Nanoscale ; 16(6): 2955-2965, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38247885

RESUMO

Acute kidney injury (AKI), characterized by tissue inflammation and oxidative damage, is a common and potentially life-threatening complication in patients. Quercetin, a natural antioxidant, possesses diverse pharmacological properties. However, limited stability and bioavailability hinder its clinical utilization. Moreover, the application of nanotechnology in antioxidant strategies for AKI treatment faces significant knowledge gaps. These gaps stem from limited understanding of the therapeutic mechanisms and renal clearance pathways. To tackle these issues, this study aims to develop an anti-oxidation nanozyme through the coordination of quercetin (Que) with a ruthenium (Ru) doped platinum (Pt) nanozyme (RuPt nanozyme). Compared to using Que or the RuPt nanozyme alone, the combined use of Que and the nanozyme led to enhanced antioxidant activities, especially in ABTS and DPPH free radical scavenging activities. Moreover, the modified nanozyme showed remarkable efficacy in scavenging reactive oxygen species and inhibiting apoptosis in a H2O2-induced cellular model. Additionally, the in vivo study showed that the coordination-modified nanozyme effectively alleviated glycerol- and cisplatin-induced AKI by inhibiting oxidative stress. Furthermore, this nanozyme exhibited superior therapeutic efficacy when compared to free quercetin and the RuPt nanozyme. In conclusion, the findings of our study suggest that the quercetin modified RuPt nanozyme (QCN) exhibits remarkable biocompatibility and holds significant promise for the therapeutic management of AKI.


Assuntos
Injúria Renal Aguda , Quercetina , Humanos , Quercetina/farmacologia , Quercetina/química , Antioxidantes/química , Peróxido de Hidrogênio , Estresse Oxidativo , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Espécies Reativas de Oxigênio/metabolismo
18.
Heliyon ; 10(1): e23352, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163214

RESUMO

Background: Pulmonary arterial hypertension (PAH) leads to myocardial remodeling, manifesting as mechanical dyssynchrony (M-dys) and electrical dyssynchrony (E-dys), in both right (RV) and left ventricles (LV). However, the impacts of layer-specific intraventricular M-dys on biventricular functions and its association with E-dys in PAH remain unclear. Methods: Seventy-nine newly diagnosed patients with PAH undergoing cardiac magnetic resonance scanning were consecutively recruited between January 2011 and December 2017. The biventricular volumetric and layer-specific intraventricular M-dys were analyzed. The QRS duration z-scores were calculated after adjusting for age and sex. Results: 77.22 % of patients were female (mean age 30.30 ± 9.79 years; median follow-up 5.53 years). Further, 29 (36.71 %) patients succumbed to all-cause mortality by the end of the study. At the baseline, LV layer-specific intraventricular M-dys had apparent transmural gradients compared with RV in the radial and circumferential directions. However, deceased patients lost the transmural gradients. The LV longitudinal strain rate time to late diastolic peak in the myocardial region (LVmyoLSRTTLDPintra) predicted long-term survival. The Kaplan-Meier curve revealed that patients with PAH with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. Larger right ventricle (RV) intraventricular M-dys resulted in worse RV ejection fraction. However, larger LV intraventricular M-dys in the late diastolic phase indicated remarkable exercise capacity and higher LV stroke volume index. E-dys and intraventricular M-dys had no direct correlations. Conclusions: The layer-specific intraventricular M-dys had varying impacts on biventricular functions in PAH. PAH patients with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. LV intraventricular M-dys in the late diastolic phase needs more attention to precisely evaluate LV function.

19.
Eur J Radiol ; 170: 111206, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995514

RESUMO

PURPOSE: To investigate the imaging characteristics and prognostic factors for the long-term survival of Behcet's disease (BD) with arterial involvement. METHODS: In this retrospective study, BD patients with arterial involvement were identified from January 2003 to January 2020. Arterial lesions were detected by ultrasonography, traditional arteriography, and/or computed tomography angiography (CTA). Cox proportional hazards regression analyses were performed to identify the prognostic factors. RESULTS: Totally, 84 BD patients with arterial involvement were identified (73.8 % males). The mean age at BD diagnosis was 39.1 ± 13.1 years. Arterial involvement was the initial manifestation in 33.3 % of the patients, and the median time from BD diagnosis to arterial involvement was 6 (IQR 1-15.5) years for the rest of patients. Systemic artery involvement and pulmonary artery involvement (PAI) were found in 64 and 27 patients, respectively. Approximately 94.0 % (79/84) of the patients had more than one artery involved concurrently or successively during the course of BD. Aneurysm/dilation was the most prevalent lesion in the aorta (76.0 %), while stenosis/occlusion was the main lesion of the coronary artery (90.9 %) and other aortic branches (74.5 %). Pulmonary hypertension was found in 70.4 % (19/27) of patients with PAI. The 5- and 10-year survival rates of BD patients with arterial involvement were 87.4 % and 84.1 %, respectively. Cardiac involvement (HR: 4.34) and pulmonary artery aneurysm/dilation (HR: 4.89) were independently associated with mortality. CONCLUSIONS: Arterial lesions associated with BD usually involve multiple arteries and manifest differently in different types of arteries. Cardiac involvement and pulmonary artery aneurysm/dilation are independent prognostic factors of BD patients with arterial involvement.


Assuntos
Aneurisma , Síndrome de Behçet , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Síndrome de Behçet/diagnóstico por imagem , Seguimentos , Estudos Retrospectivos , Prognóstico , Artéria Pulmonar/diagnóstico por imagem
20.
Psychol Res Behav Manag ; 16: 5185-5196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148777

RESUMO

Purpose: Inspiration is a psychological construct that has been relatively understudied in times of difficulty. This study aims to investigate the mediating effect of inspiration on the relationship between emotions and coping strategies in the context of adversity and to testify the effect in Chinese as well as the International societies. Participants and Methods: Using the snowball sampling method, two survey studies were conducted among 523 Chinese and 503 international participants during and soon after the local Covid-19 outbreak to testify how positive and negative emotions contributed to various coping strategies and whether the experience of inspiration mediated these relations. Structural equation modeling (SEM) was used to analyze the data. Results: Positive emotions had a higher impact on problem-solving and seeking social support coping strategies, whereas negative emotions had a higher impact on avoidance coping strategy. Both positive and negative emotions had positive relationships with inspiration, but positive emotions had a higher impact than negative ones. The indirect effects of emotions on problem-solving and social support coping strategies through inspiration were significantly positive, while the avoidance coping strategy was not influenced by the experience of inspiration. Conclusion: The results suggest that being inspired in both positive and negative emotions is positively related to approach coping strategies in adverse situations such as COVID-19, with the effect patterns slightly differing between Chinese participants and their Western counterparts. This study highlights the importance of inspiration experience as a motivational state that can help individuals bring newly acquired ideas into fruition, especially during times of difficulty. By understanding the role of inspiration in the context of adversity, public health systems can better assist individuals in different societies to cope with the challenges they face.

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