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1.
Eur J Med Chem ; 280: 116961, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39447457

RESUMEN

Pancreatic cancer (PC) is an extremely lethal malignant tumor. The Hedgehog (Hh) signaling pathway is implicated in embryonic development, regulation of tumor stem cells, and modulation of the tumor microenvironment. Aberrant activation of Hh pathway leads to the development of multiple malignant tumors, especially Hh-driven PC. Targeting the molecular regulation of the Hh signaling pathway presents a promising therapeutic strategy for PC treatment. Hence, there is a high demand for novel molecules that inhibit the Hh pathway. In this study, the Hh pathway inhibitors bearing pyridyl pyrimidine skeleton were designed, synthesized, and characterized. Among them, N-(4-((dimethylamino)methyl)phenyl)-4-((4-(pyridin-3-yl)pyrimidin-2-yl)amino)benzamide (B31) emerged as the most potent analog following screening with a Gli luciferase reporter assay, competing with cyclopamine in the binding site of Smo protein. Molecular simulation revealed that B31 interacts with Smo through hydrogen bonds, hydrophobic interactions, and electrostatic forces. B31 inhibited PC cell proliferation, migration, and induced apoptosis by suppressing Gli1 expression at both the transcriptional and translational levels. Moreover, B31 significantly regressed subcutaneous tumors formed by BxPC-3 cells in nude mice without inducing toxic effects. These results underscore the enhanced efficacy of B31 in the PC model and offer a new avenue for developing effective Hh pathway inhibitors for clinical PC treatment.

2.
Seismica ; 3(2)2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39351191

RESUMEN

In the past decade, distributed acoustic sensing (DAS) has enabled many new monitoring applications in diverse fields including hydrocarbon exploration and extraction; induced, local, regional, and global seismology; infrastructure and urban monitoring; and several others. However, to date, the open-source software ecosystem for handling DAS data is relatively immature. Here we introduce DASCore, a Python library for analyzing, visualizing, and managing DAS data. DASCore implements an object-oriented interface for performing common data processing and transformations, reading and writing various DAS file types, creating simple visualizations, and managing file system-based DAS archives. DASCore also integrates with other Python-based tools which enable the processing of massive data sets in cloud environments. DASCore is the foundational package for the broader DAS data analysis ecosystem (DASDAE), and as such its main goal is to facilitate the development of other DAS libraries and applications.

3.
Sci Total Environ ; 955: 176895, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39401594

RESUMEN

Sodium p-perfluorous nonenoxybenzene sulfonate (OBS) is a prominent alternative to perfluorooctanesulfonic acid (PFOS). Numerous studies have demonstrated hepatotoxicity and neurotoxicity of OBS and PFOS in mammals. The lungs, as a sensitive organ, are among the potential target organs for OBS and PFOS exposure. However, their toxic effects on the lungs remain unclear. In the present study, three-dimensional (3D) spheroids constructed from A549 cells were exposed to OBS and PFOS for 7 days to evaluate pulmonary toxicity through morphological examination, growth kinetics, transcriptomic profiling, and biochemical assays. Our results showed that OBS significantly reduced the diameter, volume, and growth fraction of the spheroids compared to PFOS. Transcriptomic analysis revealed a notable enrichment of the IL-17 signaling pathway after 7 days of OBS exposure. Significant differences in the transcription of genes within this pathway were observed between OBS and PFOS exposure. OBS reduced the transcription of tnfaip3, nfkbiα, map3k8, enpp2, jun, il6, cxcl1, cxcl2, cxcl3, and cxcl8 in the IL-17 signaling pathway, while PFOS enhanced the transcription of nfkbiα. Additionally, OBS decreased the level of IL-8, whereas PFOS had a minor effect. Cluster analysis confirmed significant differences in the pulmonary toxicity between OBS and PFOS. Our study demonstrated the utility of spheroids as an in vitro cell model complemented with omics technology, for comparing the pulmonary toxicity of OBS and PFOS. It provided a novel approach for evaluating the pulmonary toxicity of new pollutants like OBS.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(5): 1614-1617, 2024 Oct.
Artículo en Chino | MEDLINE | ID: mdl-39479856

RESUMEN

Research on the participation of exosomes in pathogenesis and prognosis of multiple myeloma (MM) has made encouraging progress. However, the specific mechanism has not yet been clarified. Recently, domestic and foreign researchers have pressed forward on deeper study on exosomes. This article mainly summarizes the role of exosomes in the pathophysiological processes, such as bone marrow microenvironment changes, immunosuppression, myeloma bone disease generation and myeloma drug resistance, so as to provide new reference for further clinical research of exosomes as potential biomarkers for MM.


Asunto(s)
Exosomas , Mieloma Múltiple , Exosomas/metabolismo , Humanos , Microambiente Tumoral , Médula Ósea , Pronóstico , Resistencia a Antineoplásicos
5.
Artículo en Inglés | MEDLINE | ID: mdl-39233286

RESUMEN

17α-Ethinylestradiol (EE2) is known for its endocrine-disrupting effects on embryonic and adult fish. However, its impact on juvenile zebrafish has not been well established. In this study, juvenile zebrafish were exposed to EE2 at concentrations of 5 ng/L (low dose, L), 10 ng/L (medium dose, M), and 50 ng/L (high dose, H) from 21 days post-fertilization (dpf) to 49 dpf. We assessed their growth, development, behavior, transcriptome, and metabolome. The findings showed that the survival rate in the EE2-H group was 66.8 %, with all surviving fish displaying stunted growth and swollen, transparent abdomens by 49 dpf. Moreover, severe organ deformities were observed in the gills, kidneys, intestines, and heart of fish in both the EE2-H and EE2-M groups. Co-expression analysis of mRNA and lncRNA revealed that EE2 downregulated the transcription of key genes involved in the cell cycle, DNA replication, and Fanconi anemia signaling pathways. Additionally, metabolomic analysis indicated that EE2 influenced metabolism and development-related signaling pathways. These pathways were also significantly identified based on the genes regulated by lncRNA. Consequently, EE2 induced organ deformities and mortality in juvenile zebrafish by disrupting signaling pathways associated with development and metabolism. The results of this study offer new mechanistic insights into the adverse effects of EE2 on juvenile zebrafish based on multiomics analysis. The juvenile zebrafish are highly sensitive to EE2 exposure, which is not limited to adult and embryonic stages. It is a potential model for studying developmental toxicity.


Asunto(s)
Etinilestradiol , Contaminantes Químicos del Agua , Pez Cebra , Animales , Etinilestradiol/toxicidad , Contaminantes Químicos del Agua/toxicidad , Disruptores Endocrinos/toxicidad , Transcriptoma/efectos de los fármacos , Multiómica
6.
Nicotine Tob Res ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39233590

RESUMEN

INTRODUCTION: This study investigates the effects of varying nicotine doses and administration frequencies on mouse body weight, adipose tissues, and liver. METHODS: Male C57BL6/J mice received subcutaneous nicotine doses (0.5mg/kg, 1mg/kg, or 2mg/kg) once daily (qd), twice daily (bid), or four times daily (qid) for 4 weeks. Body weight, inguinal white adipose tissue (iWAT), epididymal white adipose tissue (eWAT), brown adipose tissue (BAT) weight and size, and UCP1 expression were assessed, along with liver fat deposition and morphology. RESULTS: Nicotine administration reduced body weight and decreased the weight and size of iWAT and eWAT compared to controls. The frequency of nicotine administration had a more significant impact on body weight and fat tissues than the dosage itself, with 2mg/kg bid being optimal for weight reduction. Nicotine increased BAT cell numbers and amplified UCP1 expression in iWAT and BAT. It had minor effects on eWAT UCP1 expression and no substantial impact on liver fat deposition or morphology, except for a reduction in liver weight with doses exceeding 4mg/kg. CONCLUSIONS: Nicotine-induced weight reduction is frequency-dependent, with 2mg/kg bid being the optimal regimen. The mechanisms may include reductions in iWAT and eWAT weights and cell sizes, induction of browning in iWAT, increased BAT quantity and UCP1 expression, and heightened energy expenditure in iWAT and BAT. Nicotine's ability to induce eWAT browning is relatively weak, indicating diverse mechanisms of action across different adipose tissue types. These findings provide a foundation for further exploration of nicotine's multifaceted functions and underlying mechanisms. IMPLICATIONS: This study examines how different nicotine doses and administration frequencies affect mouse body weight and adipose tissues. It finds that administering nicotine bid (twice daily) at 2mg/kg leads to optimal weight reduction. Nicotine induces browning in white adipose tissue, increases brown adipose tissue quantity and UCP1 expression, and affects energy expenditure. The findings underscore nicotine's nuanced effects across different adipose tissue types and lay groundwork for further exploration of its mechanisms and therapeutic potential in weight management.

7.
BMC Public Health ; 24(1): 2563, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300422

RESUMEN

BACKGROUND: Despite major primary health care (PHC) reforms in China with the 2009 launch of the National Essential Public Health Service Package, the country experiences many challenges in improving the management of non-communicable diseases in PHC facilities. "EMERALD" is a multifaceted implementation strategy to strengthen the management of hypertension and type-2 diabetes mellitus (T2DM) in PHC facilities. The study aims to: (1) examine the effectiveness of EMERALD in improving hypertension and T2DM management; (2) evaluate the implementation of the interventions; and (3) use the study findings to model the long-term health economic impact of the interventions. METHODS: The EMERALD intervention components include: (1) empowerment for PHC providers through training and capacity building; (2) empowerment for patient communities through multi-media health education; and  (3) empowerment for local health administrators through health data monitoring and strengthening governance of local PHC programs. An interrupted time series design will be used to determine the effectiveness of the interventions based on routinely collected health data extracted from local health information systems. The primary effectiveness outcome is the guideline-recommended treatment rates for people with hypertension and T2DM. Secondary effectiveness outcomes include hypertension and T2DM diagnosis and control rates, and enrolment and adherence rates to the recommended care processes in the National Essential Public Health Service Package. A mixed-methods process evaluation will be conducted to evaluate the implementation of the interventions, including the reach of the target population, adequacy of adoption, level of implementation fidelity, and maintenance. Qualitative interviews with policy makers, health administrators, PHC providers, and patients with hypertension and/or T2DM will be conducted to further identify factors influencing the implementation. In addition, health economic modelling will be performed to explore the long-term incremental costs and benefits of the interventions. DISCUSSION: This study is expected to generate important evidence on the effectiveness, implementation, and health economic impact of complex PHC interventions to strengthen the primary care sector's contribution to addressing the growing burden of non-communicable diseases in China. TRIAL REGISTRATION: The study has been registered on Chinese Clinical Trial Registry at https://www.chictr.org.cn/ (Registration number ChiCTR2400082036, on March 19th 2024).


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipertensión , Análisis de Series de Tiempo Interrumpido , Atención Primaria de Salud , Humanos , Hipertensión/terapia , China , Diabetes Mellitus Tipo 2/terapia , Atención Primaria de Salud/economía , Análisis Costo-Beneficio , Evaluación de Procesos, Atención de Salud
8.
Comput Biol Med ; 182: 109106, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39241326

RESUMEN

Learning using privileged information (LUPI) has shown its effectiveness to improve the B-mode ultrasound (BUS) based computer-aided diagnosis (CAD) by transferring knowledge from the elasticity ultrasound (EUS). However, LUPI only performs transfer learning between the paired data with shared labels, and cannot handle the scenario of modality imbalance. In order to conduct the supervised transfer learning between the paired ultrasound data together with the additional single-modal BUS images, a novel multi-view LUPI algorithm with Dual-Level Modality Completion, named DLMC-LUPI, is proposed to improve the performance of BUS-based CAD. The DLMC-LUPI implements both image-level and feature-level (dual-level) completions of missing EUS modality, and then performs multi-view LUPI for knowledge transfer. Specifically, in the dual-level modality completion stage, a variational autoencoder (VAE) model for feature generation and a novel generative adversarial network (VAE-based GAN) model for image generation are sequentially trained. The proposed VAE-based GAN can improve the synthesis quality of EUS images by adopting the features generated by VAE from the BUS images as the model constrain to make the features generated from the synthesized EUS images more similar to them. In the multi-view LUPI stage, two feature vectors are generated from the real or pseudo images as two source domains, and then fed them to the multi-view support vector machine plus classifier for model training. The experiments on two ultrasound datasets indicate that the DLMC-LUPI outperforms all the compared algorithms, and it can effectively improve the performance of single-modal BUS-based CAD.

9.
Adv Sci (Weinh) ; : e2404518, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225325

RESUMEN

With the increase in the aging population, senile osteoporosis (SOP) has become a major global public health concern. Here, it is found that Prx1 and Bmi-1 co-localized in trabecular bone, bone marrow cavity, endosteum, and periosteum. Prx1-driven Bmi-1 knockout in bone-marrow mesenchymal stem cells (BMSCs) reduced bone mass and increased bone marrow adiposity by inhibiting osteoblastic bone formation, promoting osteoclastic bone resorption, downregulating the proliferation and osteogenic differentiation of BMSCs, and upregulating the adipogenic differentiation of BMSCs. However, Prx1-driven Bmi-1 overexpression showed a contrasting phenotype to Prx1-driven Bmi-1 knockout in BMSCs. Regarding mechanism, Bmi-1-RING1B bound to DNMT3A and promoted its ubiquitination and inhibited DNA methylation of Runx2 at the region from 45047012 to 45047313 bp, thus promoting the osteogenic differentiation of BMSCs. Moreover, Bmi-1-EZH2 repressed the transcription of Cebpa by promoting H3K27 trimethylation at the promoter region -1605 to -1596 bp, thus inhibiting the adipogenic differentiation of BMSCs. It is also found that Prx1-driven Bmi-1 overexpression rescued the SOP induced by Prx1-driven Bmi-1 knockout in BMSCs. Thus, Bmi-1 functioned as a hub protein in the epigenetic regulation of BMSCs differentiation to delay bone aging. The Prx1-driven Bmi-1 overexpression in BMSCs can be used as an approach for the translational therapy of SOP.

10.
J Appl Physiol (1985) ; 137(5): 1285-1300, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39169840

RESUMEN

Several experimental studies have found that females have higher particle deposition in the airways than males. This has implications for the delivery of aerosolized therapeutics and for understanding sex differences in respiratory system response to environmental exposures. This study evaluates several factors that potentially contribute to sex differences in particle deposition, using scale-specific structure-function models of one-dimensional (1-D) ventilation distribution, particle transport, and deposition. The impact of gravity, inhalation flow rate, and dead space are evaluated in 12 structure-based models (7 females; 5 males). Females were found to have significantly higher total, bronchial, and alveolar deposition than males across a particle size range from 0.01 to 10 µm. Results suggest that higher deposition fraction in females is due to higher alveolar deposition for smaller particle sizes and higher bronchial deposition for larger particles. Females had higher alveolar deposition in the lower lobes and slightly lower particle concentration in the left upper lobe. Males were found to be more sensitive to changes due to gravity, showing greater reduction in bronchial deposition fraction. Males were also more sensitive to change in inhalation flow rate and to scaling of dead space due to the larger male baseline airway size. Predictions of sex differences in particle deposition-that are consistent with the literature-suggest that sex-based characteristics of lung and airway size interacting with particle size gives rise to differences in regional deposition.NEW & NOTEWORTHY Sex differences in airway tract particle deposition are analyzed using computational models that account for scale-specific structure and function. We show that sex-related differences in lung and airway size can explain experimental observations of increased deposition fraction in females, with females tending toward enhanced fine particle deposition in the alveolar airways and enhanced bronchial deposition for larger particles.


Asunto(s)
Aerosoles , Tamaño de la Partícula , Caracteres Sexuales , Femenino , Masculino , Humanos , Bronquios/metabolismo , Bronquios/fisiología , Modelos Biológicos , Pulmón/metabolismo , Pulmón/fisiología , Administración por Inhalación , Alveolos Pulmonares/metabolismo , Alveolos Pulmonares/fisiología , Factores Sexuales
11.
Food Funct ; 15(17): 8740-8758, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39101469

RESUMEN

Consuming probiotic products is a solution that people are willing to choose to augment health. As a global health hazard, sleep deprivation (SD) can cause both physical and mental diseases. The present study investigated the protective effects of Lacticaseibacillus rhamnosus GG (LGG), a widely used probiotic, on a SD mouse model. Here, it has been shown that SD induced intestinal damage in mice, while LGG supplementation attenuated disruption of the intestinal barrier and enhanced the antioxidant capacity. Microbiome analysis revealed that SD caused dysbiosis in the gut microbiota, characterized by increased levels of Clostridium XlVa, Alistipes, and Desulfovibrio, as well as decreased levels of Ruminococcus, which were partially ameliorated by LGG. Moreover, SD resulted in elevated pro-inflammatory cytokine concentrations in both the intestine and the brain, while LGG provided protection in both organs. LGG supplementation significantly improved locomotor activity in SD mice. Although heat-killed LGG showed some protective effects in SD mice, its overall efficacy was inferior to that of live LGG. In terms of mechanism, it was found that AG1478, an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, could diminish the protective effects of LGG. In conclusion, LGG demonstrated the ability to alleviate SD-induced intestinal barrier dysfunction through EGFR activation and alleviate neuroinflammation.


Asunto(s)
Microbioma Gastrointestinal , Lacticaseibacillus rhamnosus , Probióticos , Privación de Sueño , Animales , Lacticaseibacillus rhamnosus/fisiología , Ratones , Probióticos/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Enfermedades Neuroinflamatorias , Intestinos/microbiología , Ratones Endogámicos C57BL , Mucosa Intestinal/metabolismo , Disbiosis/microbiología , Modelos Animales de Enfermedad
12.
mBio ; 15(8): e0104924, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38953354

RESUMEN

Polyomaviruses are species-specific DNA viruses that can cause disease in immunocompromised individuals. Despite their role as the causative agents for several diseases, there are no currently approved antivirals for treating polyomavirus infection. Brincidofovir (BCV) is an antiviral approved for the treatment of poxvirus infections and has shown activity against other double-stranded DNA viruses. In this study, we tested the efficacy of BCV against polyomavirus infection in vitro and in vivo using mouse polyomavirus (MuPyV). BCV inhibited virus production in primary mouse kidney cells and brain cortical cells. BCV treatment of cells transfected with MuPyV genomic DNA resulted in a reduction in virus levels, indicating that viral inhibition occurs post-entry. Although in vitro BCV treatment had a limited effect on viral DNA and RNA levels, drug treatment was associated with a reduction in viral protein, raising the possibility that BCV acts post-transcriptionally to inhibit MuPyV infection. In mice, BCV treatment was well tolerated, and prophylactic treatment resulted in a reduction in viral DNA levels and a potent suppression of infectious virus production in the kidney and brain. In mice with chronic polyomavirus infection, therapeutic administration of BCV decreased viremia and reduced infection in the kidney. These data demonstrate that BCV exerts antiviral activity against polyomavirus infection in vivo, supporting further investigation into the use of BCV to treat clinical polyomavirus infections. IMPORTANCE: Widespread in the human population and able to persist asymptomatically for the life of an individual, polyomavirus infections cause a significant disease burden in the immunocompromised. Individuals undergoing immune suppression, such as kidney transplant patients or those treated for autoimmune diseases, are particularly at high risk for polyomavirus-associated diseases. Because no antiviral agent exists for treating polyomavirus infections, management of polyomavirus-associated diseases typically involves reducing or discontinuing immunomodulatory therapy. This can be perilous due to the risk of transplant rejection and the potential development of adverse immune reactions. Thus, there is a pressing need for the development of antivirals targeting polyomaviruses. Here, we investigate the effects of brincidofovir, an FDA-approved antiviral, on polyomavirus infection in vivo using mouse polyomavirus. We show that the drug is well-tolerated in mice, reduces infectious viral titers, and limits viral pathology, indicating the potential of brincidofovir as an anti-polyomavirus therapeutic.


Asunto(s)
Antivirales , Citosina , Organofosfonatos , Infecciones por Polyomavirus , Poliomavirus , Animales , Citosina/análogos & derivados , Citosina/farmacología , Citosina/uso terapéutico , Infecciones por Polyomavirus/tratamiento farmacológico , Infecciones por Polyomavirus/virología , Poliomavirus/efectos de los fármacos , Ratones , Antivirales/farmacología , Antivirales/uso terapéutico , Organofosfonatos/farmacología , Organofosfonatos/uso terapéutico , Replicación Viral/efectos de los fármacos , Riñón/virología , Riñón/efectos de los fármacos , Femenino , ADN Viral/genética , Células Cultivadas , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Encéfalo/virología
13.
Front Pediatr ; 12: 1414177, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39022216

RESUMEN

The infant and child stage is an important stage for the continuation and development of human society. The initial years of life have a lasting impact on a child's future. Children under the age of 5 have an immature immune system, especially infants and young children under 6 months of age. At this stage, the population has a low immunity to pathogen infections, making them vulnerable to bacteria and viruses. Vaccination can enhance the immunity of infants and children to specific diseases, reduce the transmission rate of infectious diseases, and promote the development of global public health. This article summarizes the current application status of Rotavirus (RV) vaccine, Hand-foot -mouth disease (HFMD) vaccine, and Pneumococcal Conjugate Vaccine (PCV) in China, as well as the research progress of clinical trial vaccine, laying a foundation for subsequent vaccine development.

14.
Lancet Reg Health West Pac ; 49: 101131, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39056090

RESUMEN

Background: Policy makers and researchers are tasked with exploring ways to strengthen primary health care (PHC) to address the growing burden of non-communicable diseases (NCDs). This study aims to use a co-design approach (i.e., meaningful involvement of research end users in study planning and design) to develop PHC interventions to improve the management of hypertension and type 2 diabetes (T2DM) in four study sites in China. Methods: The study adopted a three-step co-design approach, including (1) a two-round Delphi panel with health system and NCD professionals to identify prioritised health system challenges, (2) three co-design workshops (in each study site) with local health administrators, PHC providers, and residents with hypertension and/or T2DM, respectively, to develop interventions and identify factors influencing implementation, and (3) another round of co-design workshops with local health administrators to summarise findings and reach consensus. Qualitative synthesis was conducted to analyse results from the workshops. Findings: Thirteen experts were involved in the two-round Delphi panel, which identified three prioritised health system challenges, including limited capacities of PHC providers, suboptimal service quality and evaluation mechanisms, and unreliable health information systems. The co-design workshops involved 116 local stakeholders in 16 sessions (four in each site), and developed three groups of interventions to address the challenges: (1) empowering PHC providers through on-the-job training for capacity building; (2) empowering patient communities through health education on healthy lifestyles and NCD self-management; and (3) empowering health administrators through local health data monitoring and strengthening governance for local PHC programs. Site-specific interventions were also considered to cater for different local contexts. Several recommendations were further identified for the implementation of these interventions, emphasising the importance of local customisation, community participation, and cross-sectoral collaborations. Interpretation: By engaging multiple stakeholders in priority setting and solution generation, this study summarised several key areas for change in health workforce, service delivery, and health information. Future research should examine the effectiveness and implementation of these interventions to improve NCD management in PHC in China. Funding: This study is funded by National Health and Medical Research Council (NHMRC) Global Alliance for Chronic Diseases funding (APP1169757) and National Natural Science Foundation of China (72074065). Shangzhi Xiong is supported by University of New South Wales tuition fee scholarship.

15.
Entropy (Basel) ; 26(7)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39056952

RESUMEN

While collecting training data, even with the manual verification of experts from crowdsourcing platforms, eliminating incorrect annotations (noisy labels) completely is difficult and expensive. In dealing with datasets that contain noisy labels, over-parameterized deep neural networks (DNNs) tend to overfit, leading to poor generalization and classification performance. As a result, noisy label learning (NLL) has received significant attention in recent years. Existing research shows that although DNNs eventually fit all training data, they first prioritize fitting clean samples, then gradually overfit to noisy samples. Mainstream methods utilize this characteristic to divide training data but face two issues: class imbalance in the segmented data subsets and the optimization conflict between unsupervised contrastive representation learning and supervised learning. To address these issues, we propose a Balanced Partitioning and Training framework with Pseudo-Label Relaxed contrastive loss called BPT-PLR, which includes two crucial processes: a balanced partitioning process with a two-dimensional Gaussian mixture model (BP-GMM) and a semi-supervised oversampling training process with a pseudo-label relaxed contrastive loss (SSO-PLR). The former utilizes both semantic feature information and model prediction results to identify noisy labels, introducing a balancing strategy to maintain class balance in the divided subsets as much as possible. The latter adopts the latest pseudo-label relaxed contrastive loss to replace unsupervised contrastive loss, reducing optimization conflicts between semi-supervised and unsupervised contrastive losses to improve performance. We validate the effectiveness of BPT-PLR on four benchmark datasets in the NLL field: CIFAR-10/100, Animal-10N, and Clothing1M. Extensive experiments comparing with state-of-the-art methods demonstrate that BPT-PLR can achieve optimal or near-optimal performance.

16.
Sensors (Basel) ; 24(11)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38894191

RESUMEN

This article discusses the use of distributed acoustic sensing (DAS) for monitoring gas-liquid two-phase slug flow in horizontal pipes, using standard telecommunication fiber optics connected to a DAS integrator for data acquisition. The experiments were performed in a 14 m long, 5 cm diameter transparent PVC pipe with a fiber cable helically wrapped around the pipe. Using mineral oil and compressed air, the system captured various flow rates and gas-oil ratios. New algorithms were developed to characterize slug flow using DAS data, including slug frequency, translational velocity, and the lengths of slug body, slug unit, and the liquid film region that had never been discussed previously. This study employed a high-speed camera next to the fiber cable sensing section for validation purposes and achieved a good correlation among the measurements under all conditions tested. Compared to traditional multiphase flow sensors, this technology is non-intrusive and offers continuous, real-time measurement across long distances and in harsh environments, such as subsurface or downhole conditions. It is cost-effective, particularly where multiple measurement points are required. Characterizing slug flow in real time is crucial to many industries that suffer slug-flow-related issues. This research demonstrated the DAS's potential to characterize slug flow quantitively. It will offer the industry a more optimal solution for facility design and operation and ensure safer operational practices.

17.
Clin Transl Immunology ; 13(5): e1514, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38770238

RESUMEN

Coronavirus disease 2019, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected 700 million people worldwide since its outbreak in 2019. The current pandemic strains, including Omicron and its large subvariant series, exhibit strong transmission and stealth. After entering the human body, the virus first infects nasal epithelial cells and invades host cells through the angiotensin-converting enzyme 2 receptor and transmembrane serine protease 2 on the host cell surface. The nasal cavity is an important body part that protects against the virus. Immunisation of the nasal mucosa produces immunoglobulin A antibodies that effectively neutralise viruses. Saline nasal irrigation, a type of physical therapy, can reduce the viral load in the nasal cavity and prevent viral infections to some extent. As a commonly used means to fight SARS-CoV-2, the intramuscular (IM) vaccine can induce the human body to produce a systemic immune response and immunoglobulin G antibody; however, the antibody is difficult to distribute to the nasal mucosa in time and cannot achieve a good preventive effect. Intranasal (IN) vaccines compensate for the shortcomings of IM vaccines, induce mucosal immune responses, and have a better effect in preventing infection. In this review, we discuss the nasal defence barrier, the harm caused by SARS-CoV-2, the mechanism of its invasion into host cells, nasal cleaning, IM vaccines and IN vaccines, and suggest increasing the development of IN vaccines, and use of IN vaccines as a supplement to IM vaccines.

18.
Materials (Basel) ; 17(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38591616

RESUMEN

Nowadays, high-pressure hydrogen storage is the most commercially used technology owing to its high hydrogen purity, rapid charging/discharging of hydrogen, and low-cost manufacturing. Despite numerous reviews on hydrogen storage technologies, there is a relative scarcity of comprehensive examinations specifically focused on high-pressure gaseous hydrogen storage and its associated materials. This article systematically presents the manufacturing processes and materials used for a variety of high-pressure hydrogen storage containers, including metal cylinders, carbon fiber composite cylinders, and emerging glass material-based hydrogen storage containers. Furthermore, it introduces the relevant principles and theoretical studies, showcasing their advantages and disadvantages compared to conventional high-pressure hydrogen storage containers. Finally, this article provides an outlook on the future development of high-pressure hydrogen storage containers.

19.
Zhongguo Zhong Yao Za Zhi ; 49(4): 1082-1090, 2024 Feb.
Artículo en Chino | MEDLINE | ID: mdl-38621915

RESUMEN

This study aims to investigate the impact of Kuntai Capsules(KTC) on polycystic ovarian syndrome(PCOS) rat models and explore the underlying mechanism. Fifty female SD rats were randomly divided into five groups(10 rats in each group), including control group, model group, low-, medium-, and high-dose KTC group. Except for the control group, the other groups were injected with dehydroepiandrosterone(DHEA) combined with a high-fat diet(HFD) to induce the PCOS rat model for 28 days. 0.315, 0.63, and 1.26 g·kg~(-1)·d~(-1) KTC was dissolved in the same amount of normal saline and given to low-, medium-, and high-dose KTC groups by gavage. Both control group and model group were given the same amount of normal saline for 15 days. After administration, fasting blood glucose(FBG) was measured by a glucose meter. Fasting insulin(FINS), luteinizing hormone(LH), testosterone(T), and follicle-stimulating hormone(FSH) were detected by enzyme-linked immunosorbent assay(ELISA), and LH/FSH ratio and insulin resistance index(HOMA-IR) were calculated. The pathological morphology of ovarian tissue was observed by hematoxylin-eosin(HE) staining. The expression levels of collagen α type Ⅲ 1 chain(COL3A1), apoptotic factors Bax, and Bcl-2 were detected using Western blot and immunofluorescence. The mRNA expressions of COL3A1, Bax, and Bcl-2 in ovarian tissue were performed by real-time PCR(RT-PCR). The results show that compared with the control group, the body weight, serum levels of FBG, FINS, LH, T, LH/FSH, and HOMA-IR are higher in model group(P<0.05 or P<0.01), and the level of FSH is lower(P<0.05). In model group, a large number of white blood cells are found in the vaginal exfoliated cells, mainly in the interictal phase. There are more cystic prominences on the surface of the ovary. The thickness of the granular cell layer is reduced, and oocytes are absent. COL3A1 and Bax protein expression levels are increased(P<0.01), while Bcl-2 protein expression levels are decreased(P<0.05) in the ovarian tissue COL3A1 and Bax mRNA expression levels are increased in ovarian tissue(P<0.05). Compared with the model group, the body weight, FBG, FINS, LH, T, LH/FSH, and HOMA-IR in low-, medium-, and high-dose KTC groups are decreased(P<0.05 or P<0.01), while the levels of FSH in medium-, and high-dose KTC groups are increased(P<0.05 or P<0.01). Low-, medium-, and high-dose KTC groups gradually show a stable interictal phase. The surface of the ovary is smooth. Oocytes and mature follicles can be seen in ovarian tissue, and the thickness of the granular cell layer is increased. The expression level of COL3A1 protein decreases in low-and medium-dose KTC groups(P<0.05 or P<0.01), and that of Bax protein decreases in low-dose KTC group(P<0.05 or P<0.01), and the expression level of Bcl-2 protein increases in low-dose KTC group(P<0.01). The expression levels of COL3A1 and Bax mRNA decreased in the low-dose KTC group(P<0.05), while the expression levels of Bcl-2 mRNA increased(P<0.05). In summary, KTC can inhibit ovarian granulosa cell apoptosis and reduce follicular atresia by regulating the AGE-RAGE signaling pathway. It can promote insulin secretion, reduce blood sugar and body weight, restore serum hormone levels, improve symptoms of PCOS, alleviate morphological damage of the ovary, and restore ovarian function, which is of great value in the treatment of PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Ratas , Femenino , Animales , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/genética , Proteína X Asociada a bcl-2 , Solución Salina , Ratas Sprague-Dawley , Atresia Folicular , Transducción de Señal , Peso Corporal , Hormona Folículo Estimulante , ARN Mensajero
20.
J Colloid Interface Sci ; 667: 22-31, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38615620

RESUMEN

Recently, there has been a significant increase in interest in using photocatalysis for the energy conversion of polluting gases. In this research, sodium and ruthenium bimetallic functional sites co-modified bismuth tungstate (Ru/Na-Bi2WO6) nanoflower photocatalyst was synthesized via the hydrothermal method. The CO2 reduction products on the Bi2WO6 substrate were CO (1.66 µmol/g/h, 68 %) and CH4 (0.78 µmol/g/h, 32 %). After optimization, a significant change in the CO2 products of the Bi2WO6-based composite material was observed, with CO (0.61 µmol/g/h, 3.6 %) and CH4 (16.1 µmol/g/h, 96.4 %). Results showed that the dominance of CH4 as the main product in the Ru/Na-BWO system is attributed to the effective doping of Na, which generates impurity energy levels composed of oxygen vacancies, lowering the conduction band position of Bi2WO6, thereby suppressing CO generation, and enhancing CH4 selectivity by changing the CO2 activation pathway. The remarkable performance is ascribed to the synergized adsorption and activation of CO2 by the tandem Na+ sites and Ru0 sites. Specifically, the doped Na+ sites play a major role in promoting the adsorption CO2 molecules, while the Ru0 sites play a dominant role in facilitating the activation of the intermediates.

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