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1.
Small ; : e2402430, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623987

RESUMO

The electronic states of metal catalysts can be redistributed by the rectifying contact between metal and semiconductor e.g., N-doped carbon (NC), while the interfacial regulation degree is very limited. Herein, a deep electronic state regulation is achieved by constructing a novel double-heterojunctional Co/Co3O4@NC catalyst containing Co/Co3O4 and Co3O4/NC heterojunctions. When used for dilute electrochemical NO3 - reduction reaction (NO3RR), the as-prepared Co/Co3O4@NC exhibits an outstanding Faradaic efficiency for NH3 formation (FENH3) of 97.9%, -0.4 V versus RHE and significant NH3 yield of 303.5 mmol h-1 gcat -1 at -0.6 V at extremely low nitrate concentrations (100 ppm NO3 --N). Experimental and theoretical results reveal that the dual junctions of Co/Co3O4 and Co3O4/NC drive a unidirectional electron transfer from Co to NC (Co→Co3O4→NC), resulting in electron-deficient Co atoms. The electron-deficient Co promotes NO3 - adsorption, the rate-determining step (RDS) for NO3RR, facilitating the dilute NO3RR to NH3. The design strategy provides a novel reference for unidirectional multistage regulation of metal electronic states boosting electrochemical dilute NO3RR, which opens up an avenue for deep electronic state regulation of electrocatalyst breaking the limitation of the electronic regulation degree by rectifying contact.

2.
Huan Jing Ke Xue ; 45(5): 2793-2805, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629542

RESUMO

The purpose of this study was to reveal the spatial and temporal evolution patterns of habitat quality in karst counties of Guizhou plateau and its driving factors and to provide scientific basis for balanced ecological conservation and sustainable development of karst regions. Using DEM data, meteorological data, socio-economic data, and four periods of land use data in 1989, 2003, 2010, and 2020, the InVEST model was used to analyze the spatial and temporal evolution characteristics of habitat quality in Puding County from 1989 to 2020 and to quantitatively detect the driving forces of its spatial divergence. The results were as follows:① Arable land and forest land were the main land use types in Puding County, which constituted the surface cover landscape matrix. Land use changes from 2003-2010 were the most significant, among which forest land had the largest increase of 86.42%; arable land was the most severely lost land use type, with an area decrease of 157.57 km2, mainly flowing to forest land and construction land. ② From 1989 to 2020, the average value of habitat quality index in Puding County increased from 0.60 to 0.73. Spatially, the distribution pattern of "high-low-high" was generally from northeast to southwest, with the high value areas of habitat quality mainly distributed in the woodland and grassland areas in the northeast and the low value areas concentrated in the construction land in the central and south areas. ③ Land use type was the primary factor affecting the spatial and temporal distribution of habitat quality, with an explanation of 91.00%. In the interaction detection, the interaction of any two influencing factors was greater than that of individual factors alone, and the interaction between land use type and average annual precipitation was the strongest, reaching 96.00%; the interaction with lithological factors reached 94.00%, with natural and human factors jointly dominating the spatial and temporal changes in habitat quality. From the results of this study, we concluded that the habitat quality of Puding County was generally good from 1989 to 2020, and the relationship between land use type changes and habitat quality was close. Optimizing the land use structure and reducing the influence of human activities are important to improve the habitat quality of Puding County.

3.
Exp Neurol ; : 114777, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636772

RESUMO

BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH) is a devastating acute cerebrovascular event with high mortality and permanent disability rates. Higher galectin-3 levels on days 1-3 have been shown to predict the development of delayed cerebral infarction or adverse outcomes after SAH. Recent single-cell analysis of microglial transcriptomic diversity in SAH revealed that galectin could influence the development and course of neuroinflammation after SAH. METHODS: This study aimed to investigate the role and mechanism of galectin-3 in SAH and to determine whether galectin-3 inhibition prevents early brain injury by reducing microglia polarization using a mouse model of SAH and oxyhemoglobin-treated activation of mouse BV2 cells in vitro. RESULTS: We found that the expression of galectin-3 began to increase 12 h after SAH and continued to increase up to 72 h. Importantly, TD139-inhibited galectin-3 expression reduced the release of inflammatory factors in microglial cells. In the experimental SAH model, TD139 treatment alleviated neuroinflammatory damage after SAH and improved defects in neurological functions. Furthermore, we demonstrated that galectin-3 inhibition affected the activation and M1 polarization of microglial cells after SAH. TD139 treatment inhibited the expression of TLR4, p-NF-κB p65, and NF-κB p65 in microglia activated by oxyhemoglobin as well as eliminated the increased expression and phosphorylation of JAK2 and STAT3. CONCLUSION: These findings suggest that regulating microglia polarization by galectin-3 after SAH to improve neuroinflammation may be a potential therapeutic target.

4.
Molecules ; 29(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38611742

RESUMO

Tumor vaccines have been considered a promising therapeutic approach for treating cancer in recent years. With the development of sequencing technologies, tumor vaccines based on neoantigens or genomes specifically expressed in tumor cells, mainly in the form of peptides, nucleic acids, and dendritic cells, are beginning to receive widespread attention. Therefore, in this review, we have introduced different forms of neoantigen vaccines and discussed the development of these vaccines in treating cancer. Furthermore, neoantigen vaccines are influenced by factors such as antigen stability, weak immunogenicity, and biosafety in addition to sequencing technology. Hence, the biological nanomaterials, polymeric nanomaterials, inorganic nanomaterials, etc., used as vaccine carriers are principally summarized here, which may contribute to the design of neoantigen vaccines for improved stability and better efficacy.


Assuntos
Vacinas Anticâncer , Nanoestruturas , Neoplasias , Ácidos Nucleicos , Humanos , Vacinas Anticâncer/uso terapêutico , Medicina de Precisão , Nanoestruturas/uso terapêutico , Neoplasias/terapia
5.
Front Neurosci ; 18: 1364338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486967

RESUMO

In clinical practice and research, the classification and diagnosis of neurological diseases such as Parkinson's Disease (PD) and Multiple System Atrophy (MSA) have long posed a significant challenge. Currently, deep learning, as a cutting-edge technology, has demonstrated immense potential in computer-aided diagnosis of PD and MSA. However, existing methods rely heavily on manually selecting key feature slices and segmenting regions of interest. This not only increases subjectivity and complexity in the classification process but also limits the model's comprehensive analysis of global data features. To address this issue, this paper proposes a novel 3D context-aware modeling framework, named 3D-CAM. It considers 3D contextual information based on an attention mechanism. The framework, utilizing a 2D slicing-based strategy, innovatively integrates a Contextual Information Module and a Location Filtering Module. The Contextual Information Module can be applied to feature maps at any layer, effectively combining features from adjacent slices and utilizing an attention mechanism to focus on crucial features. The Location Filtering Module, on the other hand, is employed in the post-processing phase to filter significant slice segments of classification features. By employing this method in the fully automated classification of PD and MSA, an accuracy of 85.71%, a recall rate of 86.36%, and a precision of 90.48% were achieved. These results not only demonstrates potential for clinical applications, but also provides a novel perspective for medical image diagnosis, thereby offering robust support for accurate diagnosis of neurological diseases.

6.
Opt Lett ; 49(6): 1453-1456, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489423

RESUMO

Surface plasmon resonance holographic microscopy (SPRHM) has been employed to measure the refractive index but whose performance is generally limited by the metallic intrinsic loss. Herein we first, to our knowledge, utilize guided wave resonance (GWR) with low loss to realize the monitoring of the refractive index by integrating with digital holographic microscopy (DHM). By depositing a dielectric layer on a silver film, we observe a typical GWR in the dielectric layer with stronger field enhancement and higher sensitivity to the surrounding refractive index compared to the silver film-supported SPR, which agrees well with calculations. The innovative combination of the GWR and DHM contributes to the highly sensitive dynamic monitoring of the surrounding refractive index variation. Through the measurement with DHM, we found that the GWR presents an excellent sensitivity, which is 2.6 times higher than that of the SPR on the silver film. The results will pave a new pathway for digital holographic interferometry and its applications in environmental and biological detections.

7.
Chem Soc Rev ; 53(8): 3976-4019, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38450547

RESUMO

Mitochondria are essential for a diverse array of biological functions. There is increasing research focus on developing efficient tools for mitochondria-targeted detection and treatment. BODIPY dyes, known for their structural versatility and excellent spectroscopic properties, are being actively explored in this context. Numerous studies have focused on developing innovative BODIPYs that utilize optical signals for imaging mitochondria. This review presents a comprehensive overview of the progress made in this field, aiming to investigate mitochondria-related biological events. It covers key factors such as design strategies, spectroscopic properties, and cytotoxicity, as well as mechanism to facilitate their future application in organelle imaging and targeted therapy. This work is anticipated to provide valuable insights for guiding future development and facilitating further investigation into mitochondria-related biological sensing and phototherapy.

9.
Sci Rep ; 14(1): 3901, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365809

RESUMO

Disulfidptosis is a condition where dysregulated NAPDH levels and abnormal accumulation of cystine and other disulfides occur in cells with high SLC7A11 expression under glucose deficiency. This disrupts normal formation of disulfide bonds among cytoskeletal proteins, leading to histone skeleton collapse and triggering cellular apoptosis. However, the correlation between disulfidptosis and immune responses in relation to glioblastoma survival rates and immunotherapy sensitivity remains understudied. Therefore, we utilized The Cancer Genome Atlas and The Chinese Glioma Genome Atlas to identify disulfidptosis-related immune checkpoint genes and established an overall survival (OS) prediction model comprising six genes: CD276, TNFRSF 14, TNFSF14, TNFSF4, CD40, and TNFRSF18, which could also be used for predicting immunotherapy sensitivity. We identified a cohort of glioblastoma patients classified as high-risk, which exhibited an upregulation of angiogenesis, extracellular matrix remodeling, and epithelial-mesenchymal transition as well as an immunosuppressive tumor microenvironment (TME) enriched with tumor associated macrophages, tumor associated neutrophils, CD8 + T-cell exhaustion. Immunohistochemical staining of CD276 in 144 cases further validated its negative correlation with OS in glioma. Disulfidptosis has the potential to induce chronic inflammation and an immunosuppressive TME in glioblastoma.


Assuntos
Glioblastoma , Glioma , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Microambiente Tumoral/genética , Prognóstico , Fatores de Transcrição , Apoptose , Ligante OX40 , Antígenos B7
10.
J Am Chem Soc ; 146(6): 3974-3983, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38299512

RESUMO

Biologics, including proteins and antisense oligonucleotides (ASOs), face significant challenges when it comes to achieving intracellular delivery within specific organs or cells through systemic administrations. In this study, we present a novel approach for delivering proteins and ASOs to liver cells, both in vitro and in vivo, using conjugates that tether N-acetylated galactosamine (GalNAc)-functionalized, cell-penetrating polydisulfides (PDSs). The method involves the thiol-bearing cargo-mediated ring-opening polymerization of GalNAc-functionalized lipoamide monomers through the so-called aggregation-induced polymerization, leading to the formation of site-specific protein/ASO-PDS conjugates with narrow dispersity. The hepatocyte-selective intracellular delivery of the conjugates arises from a combination of factors, including first GalNAc binding with ASGPR receptors on liver cells, leading to cell immobilization, and the subsequent thiol-disulfide exchange occurring on the cell surface, promoting internalization. Our findings emphasize the critical role of the close proximity of the PDS backbone to the cell surface, as it governs the success of thiol-disulfide exchange and, consequently, cell penetration. These conjugates hold tremendous potential in overcoming the various biological barriers encountered during systemic and cell-specific delivery of biomacromolecular cargos, opening up new avenues for the diagnosis and treatment of a range of liver-targeting diseases.


Assuntos
Produtos Biológicos , Galactosamina , Galactosamina/química , Hepatócitos/metabolismo , Oligonucleotídeos Antissenso/química , Dissulfetos/metabolismo , Compostos de Sulfidrila/metabolismo , Produtos Biológicos/metabolismo
11.
J Am Chem Soc ; 146(8): 5678-5692, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38359327

RESUMO

The rapid and controlled synthesis of high-molecular-weight (HMW) polysarcosine (pSar), a potential polyethylene glycol (PEG) alternative, via the ring-opening polymerization (ROP) of N-carboxyanhydride (NCA) is rare and challenging. Here, we report the well-controlled ROP of sarcosine NCA (Sar-NCA) that is catalyzed by various carboxylic acids, which accelerate the polymerization rate up to 50 times, and enables the robust synthesis of pSar with an unprecedented ultrahigh molecular weight (UHMW) up to 586 kDa (DP ∼ 8200) and exceptionally narrow dispersity (D̵) below 1.05. Mechanistic experiments and density functional theory calculations together elucidate the role of carboxylic acid as a bifunctional catalyst that significantly facilitates proton transfer processes and avoids charge separation and suggest the ring opening of NCA, rather than decarboxylation, as the rate-determining step. UHMW pSar demonstrates improved thermal and mechanical properties over the low-molecular-weight counterparts. This work provides a simple yet highly efficient approach to UHMW pSar and generates a new fundamental understanding useful not only for the ROP of Sar-NCA but also for other NCAs.

12.
World Neurosurg ; 184: e613-e632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367857

RESUMO

BACKGROUND: Stem cells have shown tremendous potential and vast prospects in the research of intervertebral disc (IVD) regeneration and repair, attracting considerable attention in recent years. In this study, a bibliometric analysis and visualization techniques were employed to probe and analyze the hotspots and frontiers of stem cell research in IVD regeneration and repair, aiming to provide valuable references and insights for further investigations. METHODS: This study utilized the Science Citation Index Expanded from the Web of Science Core Collection database to retrieve and extract relevant literature records as research samples. Visual analysis tools such as VOSviewer 1.6.19, CiteSpace 6.2.R4, and bibliometric online analysis platforms were employed to construct scientific knowledge maps, providing a comprehensive and systematic exposition from various perspectives including collaboration networks, cocitation networks, and co-occurrence networks. RESULTS: A total of 1075 relevant studies have been published in 303 journals by 4181 authors from 1198 institutions across 54 countries/regions. Over the past 20 years, the field of research has witnessed a significant growth in annual publications and citations. China and the United States have emerged as the primary participants and contributors, with the AO Research Institute Davos, Zhejiang University, and Tokai University being the top 3 leading research institutions. The most productive and highly cited author is Sakai D, who is regarded as a key leader in this research field. The journals with the highest number of publications and citations are Spine and Biomaterials, which are considered to be high-quality and authoritative core journals in this field. The current research focuses primarily on the sources and selection of stem cells, optimization of transplantation strategies, mechanisms of IVD regeneration, and the combined application of stem cells and biomaterials. However, there are still some challenges that need to be addressed, including posttransplantation stability, assessment of regenerative effects, and translation into clinical applications. Future research will concentrate on the diversity of stem cell sources, the application of novel biomaterials, personalized treatments, and the development of gene editing technologies, among other cutting-edge directions. CONCLUSIONS: This study utilized bibliometric analysis and visualization techniques to unveil the hotspots and frontiers in the research on stem cells for IVD regeneration and repair. These research findings provide essential guidance and references for further experimental design and clinical applications. However, additional experiments and clinical studies are still needed to address the challenges and difficulties faced in the field of IVD regeneration and repair, thus offering novel strategies and approaches for the treatment of IVD diseases.


Assuntos
Disco Intervertebral , Pesquisa com Células-Tronco , Humanos , Bibliometria , Materiais Biocompatíveis , Regeneração
13.
Cell Commun Signal ; 22(1): 3, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169382

RESUMO

Primary subarachnoid hemorrhage (SAH) is a type of acute stroke, accounting for approximately 10% of cases, with high disability and mortality rate. Early brain injury (EBI) is a critical factor in determining SAH mortality; however, there are no effective treatment interventions for EBI. Based on our results, the transmission of cyclic GMP-AMP (cGAMP) from neurons to microglia is a key molecular event that triggers type I interferon response, amplifies neuroinflammation, and leads to neuronal apoptosis. Abnormal intracytoplasmic mitochondrial DNA (mtDNA) is the initiating factor of the cGAS-cGAMP-STING signaling axis. Overall, the cGAS-cGAMP-STING signaling axis is closely associated with neuroinflammation after subarachnoid hemorrhage. Targeting cGAS triggered by cytoplasmic mtDNA may be useful for comprehensive clinical treatment of patients after SAH. Further studies targeting cGAS-specific antagonists for treating SAH are warranted. Video Abstract.


Assuntos
Interferon Tipo I , Hemorragia Subaracnóidea , Humanos , Microglia , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Doenças Neuroinflamatórias , Nucleotidiltransferases/genética , DNA Mitocondrial , Neurônios
14.
Res Sq ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38260302

RESUMO

Tripartite motif-containing protein 26 (TRIM26) is an E3 ubiquitin ligase that exhibits divergent roles in various cancer types (oncogenic and anti-oncogenic). This study investigates the interaction of TRIM26 with the tumor suppressor protein p53 in colorectal cancer (CRC) cells by performing a comprehensive set of biochemical, cell-based assays, and xenograft experiments. As a result, we found that overexpression of TRIM26 significantly enhances CRC cell proliferation and colony formation, while knockdown of TRIM26 suppresses these processes. Xenograft experiments further validated the tumor-promoting role of TRIM26 in CRC. Supporting this is that TRIM26 is highly expressed in human CRC tissues as revealed by our analysis of the TCGA database. Biochemically, TRIM26 directly bound to the C-terminus of p53 and facilitated its ubiquitination, resulting in proteolytic degradation and attenuated p53 activity independently of MDM2. Also, TRIM26 increased the MDM2-mediated ubiquitination of p53 by binding to MDM2's C-terminus. This study uncovers the oncogenic potential of TRIM26 in CRC by inhibiting p53 function. Through its ubiquitin ligase activity, TRIM26 destabilizes p53, consequently promoting CRC cell proliferation and tumor growth. These findings shed light on the complex involvement of TRIM26 in cancer and identify this ubiquitin ligase as a potential therapeutic target for future development of CRC treatment.

15.
Clin Neurol Neurosurg ; 236: 108111, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38199117

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the effectiveness of endoscopic endonasal surgery (EES) for Rathke's cleft cysts (RCCs) and the advantages of detailed preoperative imaging evaluation, intraoperative personalized removal and multilevel sellar floor reconstruction. METHODS: The clinical data of 43 patients with RCCs who were treated by EES in the neurosurgery department of affiliated hospital of Jiangnan University and Wuxi No.2 People's Hospital from January 2018 to January 2023 were retrospectively analyzed. The effectiveness of EES for RCCs was analyzed by imaging information, surgical procedures, symptom improvement and complications. RESULTS: All 43 RCCs were completely removed by EES, and all clinical symptoms improved to varying degrees. Postoperative relief of headache was achieved in 23 out of 26 patients (88.5 %); there was improvement in 10 out of 13 patients with visual field disorders (76.9 %) and in 8 out of 10 patients with endocrine abnormalities (80 %). New hormonal deficiency was discovered in 7 of all the patients postoperatively. There were 8 patients with postoperative diabetes insipidus and 1 patient with cerebrospinal fluid leakage. The incidence of new hormonal dysfunction and postoperative DI in expanded EES (33.3 %, 33.3 %) was higher than it in conventional EES (4 %, 8 %) (P < 0.05). The average follow-up time was 29.1 ± 14.8 months, and there were no deaths or infections. Three patients presented with cyst recurrence on MRI. CONCLUSIONS: The clinical manifestations and imaging characteristics of RCCs are variable, and a detailed preoperative review of the imaging is helpful for the development of surgical plans. RCCs can be treated more safely and thoroughly with less trauma and complications by intraoperative personalized removal and multilevel sellar floor reconstruction. The high incidence of new hormonal dysfunction and postoperative DI may be related to the disturbance of the pituitary stalk. EES has unique advantages and high clinical application value for the treatment of RCCs.


Assuntos
Cistos do Sistema Nervoso Central , Cistos , Neoplasias Hipofisárias , Humanos , Estudos Retrospectivos , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Cistos do Sistema Nervoso Central/cirurgia , Cistos do Sistema Nervoso Central/complicações , Endoscopia , Cistos/complicações , Hipófise/diagnóstico por imagem , Hipófise/cirurgia , Neoplasias Hipofisárias/cirurgia
16.
Sci Total Environ ; 917: 170348, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38281647

RESUMO

Terrestrial ecosystem carbon storage (TECS) could significantly affect the concentration of atmospheric CO2, which is critical for climate change prediction. Along these lines, the Integrated Valuation of Ecosystem Services and Trade-offs model was employed to determine the TECS of Hainan Island (HN) from 2015 to 2050 accurately. Besides, the Future Land-use Simulation model combined with natural and anthropogenic factors was used to forecast the land-use types from 2025 to 2050 in HN by considering different Shared-socioeconomic pathway-Rrepresentative concentration pathway (SSP-RCP) scenarios. Finally, the geographical detector explored the influence mechanism concerning the TECS. Under the SSP1-RCP1.9 scenario, the TECS of HN will be gradually increased to 388.10 million tons in 2050, mainly due to the increase in forest areas and the fact that the majority of grassland in the western part of HN is being converted into forest. Under different SSP-RCP scenarios except for SSP1-RCP1.9, HN's TECS is expected to gradually decrease from 2015 to 2050, mainly due to the loss of grassland and forest in coastal low-altitude areas. From the single/pair factor perspective influenced mechanism concerning the TECS, the elevation (DEM) and DEM∩Slope were found to be the dominant single/pair factor under the SSP1-RCP1.9, SSP1-RCP2.6 and SSP2-RCP4.5 scenarios. The least distance to residential area (LDP) and LDP∩LDR (i.e. LDP and least distance to roads or railways) were found to be the dominant factors under the SSP3-RCP7.0, SSP4-RCP3.4, SSP4-RCP6.0, SSP5-RCP3.4 and SSP5-RCP8.5 scenarios. Besides, the pair factors provided a higher determinant power for TECS than a single factor. Given the results of the TECS and the influence mechanism concerning the TECS under different SSP-RCP scenarios, we suggest reasonably planning the transportation network and limiting the disorderly expansion of construction land.

17.
Quant Imaging Med Surg ; 14(1): 861-876, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223039

RESUMO

Background: Accurate classification techniques are essential for the early diagnosis and treatment of patients with diabetic retinopathy (DR). However, the limited amount of annotated DR data poses a challenge for existing deep-learning models. This article proposes a difficulty-aware and task-augmentation method based on meta-learning (DaTa-ML) model for few-shot DR classification with fundus images. Methods: The difficulty-aware (Da) method operates by dynamically modifying the cross-entropy loss function applied to learning tasks. This methodology has the ability to intelligently down-weight simpler tasks, while simultaneously prioritizing more challenging tasks. These adjustments occur automatically and aim to optimize the learning process. Additionally, the task-augmentation (Ta) method is used to enhance the meta-training process by augmenting the number of tasks through image rotation and improving the feature-extraction capability. To implement the expansion of the meta-training tasks, various task instances can be sampled during the meta-training stage. Ultimately, the proposed Ta method was introduced to optimize the initialization parameters and enhance the meta-generalization performance of the model. The DaTa-ML model showed promising results by effectively addressing the challenges associated with few-shot DR classification. Results: The Asia Pacific Tele-Ophthalmology Society (APTOS) 2019 blindness detection data set was used to evaluate the DaTa-ML model. The results showed that with only 1% of the training data (5-way, 20-shot) and a single update step (training time reduced by 90%), the DaTa-ML model had an accuracy rate of 89.6% on the test data, which is a 1.7% improvement over the transfer-learning method [i.e., residual neural network (ResNet)50 pre-trained on ImageNet], and a 16.8% improvement over scratch-built models (i.e., ResNet50 without pre-trained weights), despite having fewer trainable parameters (the parameters used by the DaTa-ML model are only 0.47% of the ResNet50 parameters). Conclusions: The DaTa-ML model provides a more efficient DR classification solution with little annotated data and has significant advantages over state-of-the-art methods. Thus, it could be used to guide and assist ophthalmologists to determine the severity of DR.

18.
Eur J Pharm Sci ; 192: 106663, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056780

RESUMO

BACKGROUND: Brozopentyl Sodium (BZP), a novel agent for ischemic stroke, has shown promising results in preclinical pharmacological studies, prompting the initiation of the first-in-human investigation. PURPOSE: This study aimed to assess the safety, tolerability, and pharmacokinetic (PK) characteristics of BZP in Chinese healthy volunteers. METHODS: The study consisted of two parts. Part I was a single-center, randomized, single-blinded, placebo-controlled, single-ascending study with six BZP dose cohorts (SAD: 25, 50, 100, 200, 300, and 400 mg). Part II was a single-center, randomized, single-blinded, placebo-controlled, multi-dose- and dose-elevated study with three BZP dose cohorts (MAD: 50, 100, and 200 mg). Doses were administered once daily on days 1 and 7 and twice daily on days 2-6. The PK properties of BZP and its bioactive metabolites, BNBP, were assessed. Safety and tolerability evaluations were also conducted. RESULTS: In the SAD study, BZP reached peak plasma concentrations (Tmax) at the end of administration, with median Tmax values ranging from 1 to 1.03 h, while BNBP reached Tmax between 1.25 to 1.38 h. The terminal half-lives (T1/2) were approximately 8 h for BZP and 15 h for BNBP. In the MAD study, steady-state plasma concentrations of BZP were reached by day 5. There was minimal accumulation of both BZP and BNBP after 7 days of administration. The area under the plasma concentration-time curve from 0 to time of the last measurable concentration (AUC0-t) and maximum plasma drug concentration (Cmax) showed dose-proportional increases for BZP but not for BNBP in both study parts. Single and multiple doses of BZP demonstrated a good safety profile and were well-tolerated. CONCLUSION: BZP displayed safety, good tolerability and predictable PK characteristics following both single and multiple ascending intravenous administrations. These findings provide a basis for further clinical development of BZP for ischemic stroke patients.


Assuntos
AVC Isquêmico , Sódio , Humanos , Infusões Intravenosas , Voluntários Saudáveis , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , China
19.
Nanomedicine (Lond) ; 19(2): 127-143, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38131290

RESUMO

Background: Photodynamic therapy (PDT) of cancer has been limited by the poor solubility of most photosensitizers, use of high drug dosages, and the pH difference between the tumor tissue microenvironment (slightly acidic) and the bloodstream. These affect cellular uptake, selectivity and singlet oxygen generation. Materials & methods: We formulated Photinia glabra-green synthesized zinc oxide-protoporphyrin IX (PG-ZnO-PP) nanoconjugates by conjugating the ZnO nanoparticles enriched with amino groups and PP. Results: PG-ZnO-PP nanoconjugates showed higher rate of reactive oxygen species generation, improved cellular uptake in the acidic pH and lower IC50 toward Eca-109 cells for PDT. Conclusion: PG-ZnO-PP nanoconjugates are a potential solution to reducing drug dosage of PP through improved drug uptake, for enhanced targetability and reduced skin photosensitivity with improved PDT efficacy.


The progress of treating cancer using light-sensitive drugs and laser light of known wavelength has been limited by the poor solubility of most light-sensitive drugs, the use of high drug dosages and the slightly acidic environment within the cancerous tissues compared with normal blood in the body. These affect the ability of drugs to accumulate in cancerous cells, and not the normal cells, and the ability to produce the oxygen species that are toxic to the cancerous cells. In this paper, we prepared nanoparticles from zinc acetate using Photinia glabra (PG) fruit extract which were then used to chemically react with a light-sensitive drug called protoporphyrin IX (PP) to formulate small particles known as PG­zinc oxide (ZnO)­PP nanoconjugates. Our results showed that PG­ZnO­PP nanoconjugates had the ability to produce the toxic oxygen particles at a high rate and in good quantity. They also had a higher capability to accumulate in the cancerous cells at a pH below 7 with lower values of the drug needed to cause 50% of cell death toward the cancerous cells which affect the tube that connects from the throat to the stomach when projected with laser light. We could consider PG­ZnO­PP nanoconjugates to serve as a potential solution for reducing the dosage of PP needed to treat cancer in the presence of laser light, and at the same time they can help to reduce the skin-related side effects for patients after treatment when exposed to light.


Assuntos
Neoplasias , Photinia , Fotoquimioterapia , Protoporfirinas , Óxido de Zinco , Nanoconjugados , Óxidos , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular Tumoral , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico
20.
BMC Cancer ; 23(1): 1220, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082377

RESUMO

OBJECTIVE: The aim of this study is to evaluate an AAV vector that can selectively target breast cancer cells and to investigate its specificity and anti-tumor effects on breast cancer cells both in vitro and in vivo, offering a new therapeutic approach for the treatment of EpCAM-positive breast cancer. METHODS: In this study, a modified AAV2 viral vector was used, in which EpCAM-specific DARPin EC1 was fused to the VP2 protein of AAV2, creating a viral vector that can target breast cancer cells. The targeting ability and anti-tumor effects of this viral vector were evaluated through in vitro and in vivo experiments. RESULTS: The experimental results showed that the AAV2MEC1 virus could specifically infect EpCAM-positive breast cancer cells and accurately deliver the suicide gene HSV-TK to tumor tissue in mice, significantly inhibiting tumor growth. Compared to the traditional AAV2 viral vector, the AAV2MEC1 virus exhibited reduced accumulation in liver tissue and had no impact on tumor growth. CONCLUSION: This study demonstrates that AAV2MEC1 is a gene delivery vector capable of targeting breast cancer cells and achieving selective targeting in mice. The findings offer a potential gene delivery system and strategies for gene therapy targeting EpCAM-positive breast cancer and other tumor types.


Assuntos
Neoplasias da Mama , Proteínas de Repetição de Anquirina Projetadas , Humanos , Camundongos , Animais , Feminino , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos/genética , Dependovirus/genética , Dependovirus/metabolismo
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