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1.
Cell ; 187(19): 5267-5281.e13, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39127037

RESUMEN

The nuclear pore complex (NPC) is the sole mediator of nucleocytoplasmic transport. Despite great advances in understanding its conserved core architecture, the peripheral regions can exhibit considerable variation within and between species. One such structure is the cage-like nuclear basket. Despite its crucial roles in mRNA surveillance and chromatin organization, an architectural understanding has remained elusive. Using in-cell cryo-electron tomography and subtomogram analysis, we explored the NPC's structural variations and the nuclear basket across fungi (yeast; S. cerevisiae), mammals (mouse; M. musculus), and protozoa (T. gondii). Using integrative structural modeling, we computed a model of the basket in yeast and mammals that revealed how a hub of nucleoporins (Nups) in the nuclear ring binds to basket-forming Mlp/Tpr proteins: the coiled-coil domains of Mlp/Tpr form the struts of the basket, while their unstructured termini constitute the basket distal densities, which potentially serve as a docking site for mRNA preprocessing before nucleocytoplasmic transport.


Asunto(s)
Transporte Activo de Núcleo Celular , Proteínas de Complejo Poro Nuclear , Poro Nuclear , Saccharomyces cerevisiae , Animales , Poro Nuclear/metabolismo , Poro Nuclear/ultraestructura , Poro Nuclear/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas de Complejo Poro Nuclear/química , Ratones , Núcleo Celular/metabolismo , Toxoplasma/metabolismo , Toxoplasma/ultraestructura , Microscopía por Crioelectrón , ARN Mensajero/metabolismo , Modelos Moleculares , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/ultraestructura
2.
Nat Methods ; 20(2): 268-275, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36646896

RESUMEN

Cryo-electron tomography (cryo-ET) is a revolutionary technique for resolving the structure of subcellular organelles and macromolecular complexes in their cellular context. However, the application of the cryo-ET is hampered by the sample preparation step. Performing cryo-focused ion beam milling at an arbitrary position on the sample is inefficient, and the target of interest is not guaranteed to be preserved when thinning the cell from several micrometers to less than 300 nm thick. Here, we report a cryogenic correlated light, ion and electron microscopy (cryo-CLIEM) technique that is capable of preparing cryo-lamellae under the guidance of three-dimensional confocal imaging. Moreover, we demonstrate a workflow to preselect and preserve nanoscale target regions inside the finished cryo-lamellae. By successfully preparing cryo-lamellae that contain a single centriole or contact sites between subcellular organelles, we show that this approach is generally applicable, and shall help in innovating more applications of cryo-ET.


Asunto(s)
Tomografía con Microscopio Electrónico , Manejo de Especímenes , Tomografía con Microscopio Electrónico/métodos , Sustancias Macromoleculares/química , Manejo de Especímenes/métodos , Electrones , Imagenología Tridimensional/métodos , Microscopía por Crioelectrón/métodos
3.
Proc Natl Acad Sci U S A ; 120(48): e2307389120, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37983515

RESUMEN

Granulocytes are indispensable for various immune responses. Unlike other cell types in the body, the nuclei of granulocytes, particularly neutrophils, are heavily segmented into multiple lobes. Although this distinct morphological feature has long been observed, the underlying mechanism remains incompletely characterized. In this study, we utilize cryo-electron tomography to examine the nuclei of mouse neutrophils, revealing the cytoplasmic enrichment of intermediate filaments on the concave regions of the nuclear envelope. Aided by expression profiling and immuno-electron microscopy, we then elucidate that the intermediate-filament protein vimentin is responsible for such perinuclear structures. Of importance, exogenously expressed vimentin in nonimmune cells is sufficient to form cytoplasmic filaments wrapping on the concave nuclear surface. Moreover, genetic deletion of the protein causes a significant reduction of the number of nuclear lobes in neutrophils and eosinophils, mimicking the hematological condition of the Pelger-Huët anomaly. These results have uncovered a new component establishing the nuclear segmentation of granulocytes.


Asunto(s)
Filamentos Intermedios , Neutrófilos , Animales , Ratones , Neutrófilos/metabolismo , Vimentina/metabolismo , Núcleo Celular , Eosinófilos
4.
Environ Toxicol ; 38(12): 2967-2980, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37598414

RESUMEN

Radiation-induced lung injury (RILI) is a common side effect in thoracic tumor patients undergoing radiotherapy. At present, there is no ideal radio-protective agent which is widely used in RILI treatment. Astilbin (AST), a bioactive flavonoid, exhibits various biological effects, including anti-inflammatory, antioxidant, and anti-fibrotic activities, which partly result from reducing oxidative stress and inflammation in various pathogenic conditions. However, the protective efficacy of AST to ameliorate RILI has not been reported. In this study, we employed network pharmacology, RNA sequencing, and experimental evaluation to reveal the effects and pharmacological mechanism of AST to treat RILI in vivo and in vitro. We observed that AST reduced radiation-induced apoptosis, DNA damage, inflammatory reactions, and the reactive oxygen species (ROS) level in human normal lung epithelial cells BEAS-2B. Further study showed that AST treatment significantly ameliorated RILI by reducing the radiation-induced pathology changes and inflammatory reaction of lung tissue in C57BL/6J mice. Mechanistically, the expression of epithelial-mesenchymal transition (EMT) markers and radiation-triggered acetylation of the p53 protein were alleviated by AST treatment. Furthermore, AST alleviated the acetylation of p53 after intervention of Trichostatin A (TSA). Our data indicate that AST can alleviate RILI by inhibiting inflammatory reactions and the EMT process through decreasing the expression of p53 acetylation. In conclusion, our study suggests that AST has great potential to be a new protective and therapeutic compound for RILI.


Asunto(s)
Lesión Pulmonar , Traumatismos por Radiación , Animales , Ratones , Humanos , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/prevención & control , Lesión Pulmonar/metabolismo , Acetilación , Proteína p53 Supresora de Tumor/metabolismo , Ratones Endogámicos C57BL , Pulmón/patología , Traumatismos por Radiación/tratamiento farmacológico , Inflamación/metabolismo
5.
Genomics ; 113(4): 2547-2560, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34029696

RESUMEN

Water quality parameter dynamics, gut, sediment and water bacteria communities were studied to understand the environmental influence on the gut microbial community of a new strain of Huanghe common carp. A total of 3,384,078 raw tags and 5105 OTUs were obtained for the gut, water and sediment bacteria. The water quality had a stronger influence on the water bacteria community than gut and sediment bacteria communities. The ambient water quality parameters also significantly influenced the water and sediment bacteria communities. Comparing the gut, sediment, and water microbial communities, a relationship was found among them. However, gut bacteria were more closely related to sediment bacterial communities than to water bacteria communities. The results showed that the top three bacterial taxa were identical in gut and sediment samples in the early days of rearing. Interestingly, bacterial communities in the carp gut, water, and sediment had different adaptabilities to variations in environmental factors.


Asunto(s)
Carpas , Microbiota , Agricultura , Animales , Bacterias/genética , Estanques , ARN Ribosómico 16S/genética
6.
Prep Biochem Biotechnol ; 51(2): 120-126, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33342390

RESUMEN

Ginseng (Panax ginseng C. A. Meyer) is a famous Traditional Chinese Medicine, which is widely used to treat cardiovascular disease. Monascus ruber (M. ruber) is a fungus used in food and medicine fermentation, and lovastatin, its metabolite, is used extensively in the treatment of dyslipidemia. In this study, ginseng has been fermented by M. ruber, and the response surface methodology (RSM) was applied to optimize fermentation parameters to obtain optimal fermentation system, with further exploring to lipid-lowering activity of P. ginseng C. A. Meyer-M. ruber fermentation products (PM). The concentration of ginseng, temperature, and rotating speed were set as variables and the lovastatin yield was optimized by a Box-Behnken design (BBD) analyzed by RSM. The binding capacity of PM for sodium taurocholate and sodium cholate was assayed by UV spectrophotometry. The highest content of lovastatin production (85.53 µg g-1) was obtained at a ginseng concentration of 1.96%, temperature of 30.11 °C, and a rotating speed of 160.47 rpm. PM exhibited bile acid binding capacity, which was stronger than unfermented ginseng. The RSM can be used to optimize the fermentation system to obtain the best fermentation process. In addition, the fermentation of ginseng by M. ruber can enhance the lipid-lowering effect.


Asunto(s)
Ácidos y Sales Biliares/química , Fermentación , Lovastatina/química , Monascus/metabolismo , Reactores Biológicos , Biotecnología/métodos , Química Farmacéutica/métodos , Técnicas In Vitro , Lípidos/química , Medicina Tradicional China , Oryza , Panax , Unión Proteica , Colato de Sodio/química , Espectrofotometría Ultravioleta , Ácido Taurocólico/química , Temperatura
7.
Parasitol Res ; 114(10): 3807-13, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26202840

RESUMEN

With the accelerated movement of population, human parasitoses become an increasingly serious public health's problem. Currently, detections of parasite eggs through microscopic images are still the golden standard for diagnoses. However, this conventional method relies heavily on the experiences of inspectors, thus giving rise to misdiagnoses and missed diagnoses occasionally. And, as the number of clinical specimens increases rapidly, manual identification seems impractical. Hence, a fully automatic method is in desperate need. In this paper, we propose a robust method to segment and recognize the parasite eggs. Their contours are extracted using phase coherence technology, and the support vector machine (SVM) method based on shape and texture features is employed to classification of parasite eggs. Our novel method was comparable to the traditional method. The overall recognition rate was up to 95%, and the overall robustness indexes, including si, fnvf, fvpf, tpvf, were 95.7, 4.9, 3.7, 95.1, respectively, suggesting that our method is effective and the robustness is good, which has great potential to become a diagnostic method in the parasitological clinic.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Microscopía/métodos , Óvulo/clasificación , Óvulo/citología , Enfermedades Parasitarias/diagnóstico , Animales , Humanos , Enfermedades Parasitarias/parasitología
8.
Comput Biol Med ; 170: 107988, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38232452

RESUMEN

Nowadays, skin disease is becoming one of the most malignant diseases that threaten people's health. Computer aided diagnosis based on deep learning has become a widely used technology to assist medical professionals in diagnosis, and segmentation of lesion areas is one of the most important steps in it. However, traditional medical image segmentation methods rely on numerous pixel-level labels for fully supervised training, and such labeling process is time-consuming and requires professional competence. In order to reduce the costs of pixel-level labeling, we proposed a method only using image-level label to segment skin lesion areas. Due to the lack of lesion's spatial and intensity information in image-level labels, and the wide distribution range of irregular shape and different texture on skin lesions, the algorithm must pay great attention to the automatic lesion localization and perception of lesion boundary. In this paper, we proposed a Self-Guided Multiple Information Aggregation Network (SG-MIAN). Our backbone network MIAN utilizes the Multiple Spatial Perceptron (MSP) solely using classification information as guidance to discriminate the key classification features of lesion areas, and thereby performing more accurate localization and activation of lesion areas. Additionally, adjunct to MSP, we also proposed an Auxiliary Activation Structure (AAS) and two auxiliary loss functions to further self-guided boundary correction, achieving the goal of accurate boundary activation. To verify the effectiveness of the proposed method, we conducted extensive experiments using the HAM10000 dataset and the PH2dataset, which demonstrated superior performance compared to most existing weakly supervised segmentation methods.


Asunto(s)
Nitrosaminas , Enfermedades de la Piel , Humanos , Enfermedades de la Piel/diagnóstico por imagen , Algoritmos , Diagnóstico por Computador , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador
9.
Neoplasia ; 56: 101034, 2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-39128424

RESUMEN

BACKGROUND: Radiotherapy is the primary treatment for patients with nasopharyngeal carcinoma (NPC); however, almost 20% of patients experience treatment failure due to radioresistance. Therefore, understanding the mechanisms of radioresistance is imperative. HOTAIRM1 is deregulated in various human cancers, yet its role in NPC radioresistance are largely unclear. METHODS: This study investigated the association between HOTAIRM1 and radioresistance using CCK8, flow cytometry, and comet assays. Additionally, xenograft mice and patient-derived xenografts (PDX) models were employed to elucidate the biological functions of HOTAIRM1, and transcriptomic RNA sequencing was utilized to identify its target genes. RESULTS: Our study revealed an upregulation of HOTAIRM1 levels in radioresistant NPC cell lines and tissues. Furthermore, a positive correlation was noted between high HOTAIRM1 expression and increased NPC cell proliferation, reduced apoptosis, G2/M cell cycle arrest, and diminished cellular DNA damage following radiotherapy. HOTAIRM1 modulates the acetylation and stability of the FTO protein, and inhibiting FTO elevates the m6A methylation level of CD44 precursor transcripts in NPC cells. Additionally, silencing the m6A reading protein YTHDC1 was found to increase the expression of CD44V. HOTAIRM1 enhances NPC cell resistance to ferroptosis and irradiation through the HOTAIRM1-FTO-YTHDC1-CD44 axis. Mechanistically, HOTAIRM1 interacts with the FTO protein and induces m6A demethylation of the CD44 transcript. The absence of m6A modification in the CD44 transcript prevents its recognition by YTHDC1, resulting in the transition from CD44S to CD44V. An abundance of CD44V suppresses ferroptosis induced by irradiation and contributes to NPC radioresistance. CONCLUSIONS: In conclusion, the results in this study support the idea that HOTAIRM1 stimulates CD44 alternative splicing via FTO-mediated demethylation, thereby attenuating ferroptosis induced by irradiation and promoting NPC radioresistance.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Empalme Alternativo , Regulación Neoplásica de la Expresión Génica , Receptores de Hialuranos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Tolerancia a Radiación , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/radioterapia , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Ratones , Tolerancia a Radiación/genética , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Animales , Línea Celular Tumoral , Acetilación , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/metabolismo , Proliferación Celular , Apoptosis/genética , Ensayos Antitumor por Modelo de Xenoinjerto , MicroARNs
10.
J Ovarian Res ; 17(1): 48, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38389075

RESUMEN

BACKGROUND: Despite advances in medical imaging technology, the accurate preoperative prediction of lymph node status remains challenging in ovarian cancer. This retrospective study aimed to investigate the feasibility of using ultrasound-based radiomics combined with preoperative clinical characteristics to predict lymph node metastasis (LNM) in patients with high-grade serous ovarian cancer (HGSOC). RESULTS: Patients with 401 HGSOC lesions from two institutions were enrolled: institution 1 for the training cohort (n = 322) and institution 2 for the external test cohort (n = 79). Radiomics features were extracted from the three preoperative ultrasound images of each lesion. During feature selection, primary screening was first performed using the sample variance F-value, followed by recursive feature elimination (RFE) to filter out the 12 most significant features for predicting LNM. The radscore derived from these 12 radiomic features and three clinical characteristics were used to construct a combined model and nomogram to predict LNM, and subsequent 10-fold cross-validation was performed. In the test phase, the three models were tested with external test cohort. The radiomics model had an area under the curve (AUC) of 0.899 (95% confidence interval [CI]: 0.864-0.933) in the training cohort and 0.855 (95%CI: 0.774-0.935) in the test cohort. The combined model showed good calibration and discrimination in the training cohort (AUC = 0.930) and test cohort (AUC = 0.881), which were superior to those of the radiomic and clinical models alone. CONCLUSIONS: The nomogram consisting of the radscore and preoperative clinical characteristics showed good diagnostic performance in predicting LNM in patients with HGSOC. It may be used as a noninvasive method for assessing the lymph node status in these patients.


Asunto(s)
Nomogramas , Neoplasias Ováricas , Humanos , Femenino , Estudios Retrospectivos , Radiómica , Neoplasias Ováricas/diagnóstico por imagen , Metástasis Linfática , Ganglios Linfáticos/diagnóstico por imagen
11.
J Inflamm Res ; 17: 5567-5586, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39188632

RESUMEN

Background: Radiation-induced pulmonary fibrosis (RIPF) is a common complication after radiotherapy in thoracic cancer patients, and effective treatment methods are lacking. The purpose of this study was to investigate the protective effect of rosmarinic acid (RA) on RIPF in mice as well as the mechanism involved. Methods: m7G-tRNA-seq and tRNA-seq analyses were conducted to identify m7G-modified tRNAs. Western blotting, immunohistochemistry, northwestern blotting, northern blotting, immunofluorescence, wound-healing assays and EdU experiments were performed to explore the molecular mechanism by which RA regulates fibroblast-to-myofibroblast transformation (FMT) by affecting the exosomes of lung epithelial cells. Ribo-seq and mRNA-seq analyses were used to explore the underlying target mRNAs. Seahorse assays and immunoprecipitation were carried out to elucidate the effects of RA on glycolysis and FMT processes via the regulation of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) acetylation. Results: We found that RA had an antifibrotic effect on the lung tissues of RIPF model mice and inhibited the progression of FMT through exosomes derived from lung epithelial cells. Mechanistically, RA reduced the transcription and translation efficiency of sphingosine kinase 1 in lung fibroblasts by decreasing N7-methylguanosine modification of tRNA, downregulating the expression of tRNAs in irradiated lung epithelial cell-derived exosomes, and inhibiting the interaction between sphingosine kinase 1 and the N-acetyltransferase 10 protein in fibroblasts. Furthermore, the acetylation and cytoplasmic translocation of PFKFB3 were reduced by exosomes derived from irradiated lung epithelial cells, which following RA intervention. This suppression of the FMT process, which is triggered by glycolysis, and ultimately decelerating the progression of RIPF. Conclusion: These findings suggest that RA is a potential therapeutic agent for RIPF.

12.
Chem Biol Drug Des ; 104(1): e14576, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38969623

RESUMEN

Intestinal absorption of compounds is significant in drug research and development. To evaluate this efficiently, a method combining mathematical modeling and molecular simulation was proposed, from the perspective of molecular structure. Based on the quantitative structure-property relationship study, the model between molecular structure and their apparent permeability coefficients was successfully constructed and verified, predicting intestinal absorption of drugs and interpreting decisive structural factors, such as AlogP98, Hydrogen bond donor and Ellipsoidal volume. The molecules with strong lipophilicity, less hydrogen bond donors and receptors, and small molecular volume are more easily absorbed. Then, the molecular dynamics simulation and molecular docking were utilized to study the mechanism of differences in intestinal absorption of drugs and investigate the role of molecular structure. Results indicated that molecules with strong lipophilicity and small volume interacted with the membrane at a lower energy and were easier to penetrate the membrane. Likewise, they had weaker interaction with P-glycoprotein and were easier to escape from it and harder to export from the body. More in, less out, is the main reason these molecules absorb well.


Asunto(s)
Enlace de Hidrógeno , Absorción Intestinal , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Relación Estructura-Actividad Cuantitativa , Humanos , Estructura Molecular , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/química , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/química , Interacciones Hidrofóbicas e Hidrofílicas , Permeabilidad
13.
Int J Pharm ; 652: 123834, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38262583

RESUMEN

Umbilical paste therapy is a promising method to promote transdermal drug delivery of topical formulations. This work investigated the effect and mechanism of transdermal drug delivery through the umbilical skin. The transdermal permeation studies showed the phenomenon of higher cumulative penetration and faster penetration rates for drug through the umbilical skin compared with non-umbilical skin, namely umbilical pro-permeability. This special transdermal permeability of drugs is influenced by their molecular weight, logP value, ability to form hydrogen bonds, and molecular volume. The underlying mechanism of umbilical pro-permeability was elucidated from unique structure and regulation the effect of drugs on microcirculation in the umbilical skin. Mechanistic studies revealed that this phenomenon was not only associated with the structural and physiological properties of the skin but also to the interactions between drugs and different skin layers. The umbilical pro-permeation is attributed to the thinner stratum corneum layer, differences in stratum corneum lipid composition and keratin structure, and lower levels of intercellular tight junction proteins in the viable epidermis and dermis layer of the skin. Our research indicated that umbilical paste therapy enhanced the transdermal delivery and absorption of drugs by stimulating local blood flow through mast cell activation. Surprisingly, skin temperature modulation and calcitonin gene-related peptide and substance P levels did not appear to significantly affect this process. In conclusion, umbilical drug administration, as a straightforward and non-invasive approach to enhance transdermal drug delivery, presents novel concepts for continued investigation and practical implementation of transdermal drug delivery systems.


Asunto(s)
Absorción Cutánea , Piel , Administración Cutánea , Piel/metabolismo , Preparaciones Farmacéuticas , Epidermis/metabolismo , Permeabilidad , Sistemas de Liberación de Medicamentos
14.
bioRxiv ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38586009

RESUMEN

The nuclear pore complex (NPC) is the sole mediator of nucleocytoplasmic transport. Despite great advances in understanding its conserved core architecture, the peripheral regions can exhibit considerable variation within and between species. One such structure is the cage-like nuclear basket. Despite its crucial roles in mRNA surveillance and chromatin organization, an architectural understanding has remained elusive. Using in-cell cryo-electron tomography and subtomogram analysis, we explored the NPC's structural variations and the nuclear basket across fungi (yeast; S. cerevisiae), mammals (mouse; M. musculus), and protozoa (T. gondii). Using integrative structural modeling, we computed a model of the basket in yeast and mammals that revealed how a hub of Nups in the nuclear ring binds to basket-forming Mlp/Tpr proteins: the coiled-coil domains of Mlp/Tpr form the struts of the basket, while their unstructured termini constitute the basket distal densities, which potentially serve as a docking site for mRNA preprocessing before nucleocytoplasmic transport.

15.
Comput Biol Med ; 158: 106834, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37003067

RESUMEN

Medical image segmentation plays a crucial role in computer-aided diagnosis. However, due to the large variability of medical images, accurate segmentation is a highly challenging task. In this paper, we present a novel medical image segmentation network named the Multiple Feature Association Network (MFA-Net), which is based on deep learning techniques. The MFA-Net utilizes an encoder-decoder architecture with skip connections as its backbone network, and a parallelly dilated convolutions arrangement (PDCA) module is integrated between the encoder and the decoder to capture more representative deep features. Furthermore, a multi-scale feature restructuring module (MFRM) is introduced to restructure and fuse the deep features of the encoder. To enhance global attention perception, the proposed global attention stacking (GAS) modules are cascaded on the decoder. The proposed MFA-Net leverages novel global attention mechanisms to improve the segmentation performance at different feature scales. We evaluated our MFA-Net on four segmentation tasks, including lesions in intestinal polyp, liver tumor, prostate cancer, and skin lesion. Our experimental results and ablation study demonstrate that the proposed MFA-Net outperforms state-of-the-art methods in terms of global positioning and local edge recognition.


Asunto(s)
Neoplasias Hepáticas , Neoplasias de la Próstata , Humanos , Masculino , Diagnóstico por Computador , Procesamiento de Imagen Asistido por Computador , Neoplasias de la Próstata/diagnóstico por imagen
16.
Adv Sci (Weinh) ; 10(14): e2206595, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36840635

RESUMEN

Toxoplasma gondii (T. gondii) is the causative agent of toxoplasmosis and can infect numerous warm-blooded animals. An improved understanding of the fine structure of this parasite can help elucidate its replication mechanism. Previous studies have resolved the ultrastructure of the cytoskeleton using purified samples, which eliminates their cellular context. Here the application of cryo-electron tomography to visualize T. gondii tachyzoites in their native state is reported. The fine structure and cellular distribution of the cytoskeleton are resolved and analyzed at nanometer resolution. Additionally, the tachyzoite structural characteristics are annotated during its endodyogeny for the first time. By comparing the structural features in mature tachyzoites and their daughter buds, it is proposed that the conoid fiber of the Apicomplexa originates from microtubules. This work represents the detailed molecular anatomy of T. gondii, particularly during the budding replication stage of tachyzoite, and provides a reference for further studies of this fascinating organism.


Asunto(s)
Toxoplasma , Animales , Toxoplasma/ultraestructura , Tomografía con Microscopio Electrónico , Citoesqueleto/ultraestructura , Microtúbulos/ultraestructura
17.
Transl Oncol ; 27: 101576, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36343416

RESUMEN

Radiotherapy is a valid treatment for nasopharyngeal carcinoma (NPC), and radioresistance is the main cause of local NPC treatment failure. However, the underlying mechanisms and valuable markers of radioresistance for NPC remain have not been established. In this study, we observed that the m6A mRNA demethylase fat mass and obesity-associated protein (FTO) was significantly upregulated in radioresistant NPC tissues and cells relative to parental radiosensitive NPC tissues and cells. FTO enhances radioresistance by repressing radiation-induced ferroptosis in NPC. Mechanistically, FTO acts as an m6A demethylase to erase the m6A modification of the OTUB1 transcript and promote the expression of OTUB1, thereby inhibiting the ferroptosis of cells induced by radiation and finally triggering the radiotherapy resistance of NPC. Furthermore, our in vivo experiment results showed that the FTO inhibitor, FB23-2, and the ferroptosis activator, erastin, altered tumor responsiveness to radiotherapy in NPC cell lines and patient-derived xenografts. Our findings reveal, for the first time, that FTO enhances NPC radiotherapy resistance by withstanding radiation-induced ferroptosis, suggesting that FTO may serve as a potential therapeutic target and valuable prognostic biomarker in patients with NPC.

18.
Expert Opin Drug Deliv ; 20(5): 597-620, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37150753

RESUMEN

INTRODUCTION: Drug delivery systems (DDSs) formed by natural active compounds be instrumental in developing new green excipients and novel DDS from natural active compounds (NACs). 'Unification of medicines and excipients'(UME), the special inherent nature of the natural active compounds, provides the inspiration and conduction to achieve this goal. AREAS COVERED: This review summarizes the typical types of NACs from herbal medicine, such as saponins, flavonoids, polysaccharides, etc. that act as excipients and their main application in DDS. The comparison of the drug delivery systems formed by NACs and common materials and the primary formation mechanisms of these NACs are also introduced to provide a deepened understanding of their performance in DDS. EXPERT OPINION: Many natural bioactive compounds, such as saponins, polysaccharides, etc. have been used in DDS. Diversity of structure and pharmacological effects of NACs turn out the unique advantages in improving the performance of DDSs like targeting ability, adhesion, encapsulation efficiency(EE), etc. and enhancing the bioavailability of loaded drugs.


Asunto(s)
Sistemas de Liberación de Medicamentos , Excipientes , Excipientes/química , Preparaciones Farmacéuticas , Disponibilidad Biológica , Polisacáridos
19.
J Med Microbiol ; 71(5)2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35617337

RESUMEN

The occurrence and development of diabetic nephropathy (DN) are closely related to gut microbiota. Paecilomyces cicadae is a medicinal and edible fungus. Radix astragali is a therapeutic material for unifying Chinese Qi. They can delay the occurrence and development of kidney disease. In recent years, solid-state fermentation of edible fungi and traditional Chinese medicine has become a hot issue.Hypothesis/Gap Statement. We assumed that solid-state fermentation products of R. astragali and Paecilomyces cicadidae (RPF) could ameliorate diabetic nephropathy and modulate gut microbiota composition. We aimed to study the function and mechanism of the RPF for ameliorating DN in mice. We investigated the effect of the potential roles of RPF in DN mice and interaction between DN and gut microbiota using animal experiments and gut microbiota measurements. We found that RPF dramatically reduced urine protein, serum creatinine and blood urea nitrogen in DN mice. Furthermore, RPF ameliorated the physiological condition of DN mice by regulating the abundance of intestinal microbiota such as Ruminococcaceae_UCG-014, Allobaculum, Unclassified_f__Lachnospiraceae Alloprevotella and Bacteroides. RPF can ameliorate diabetic nephropathy and modulate gut microbiota composition.


Asunto(s)
Cordyceps , Diabetes Mellitus , Nefropatías Diabéticas , Microbioma Gastrointestinal , Animales , Astragalus propinquus , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/microbiología , Medicamentos Herbarios Chinos , Ratones
20.
Pharmaceutics ; 15(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36678754

RESUMEN

Saponins are an important class of surface-active substances. When formulated as an active ingredient or co-used with other drugs, the effect of their surface activity on efficacy or safety must be considered. In this paper, diammonium glycyrrhizinate (DG), a clinical hepatoprotective drug that has long been used as a biosurfactant, was taken as the research object to study its combined hepatoprotective effect with baicalin (BAI). Animal experiments proved that the preparation of DG and BAI integrated into micelles (BAI-DG Ms) had a better protective effect on acute liver injury caused by carbon tetrachloride than the direct combined use of the two. From the perspective of biopharmaceutics, the synergistic mechanism of BAI-DG Ms was further explored. The results showed that after forming BAI-DG Ms with DG, the solubility of BAI increased by 4.75 to 6.25 times, and the cumulative percentage release in the gastrointestinal tract also increased by 2.42 times. In addition, the negatively charged BAI-DG Ms were more likely to penetrate the mucus layer and be absorbed by endocytosis. These findings provide support for the rational application of glycyrrhizin, and other saponins.

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