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1.
J Phys Chem Lett ; : 8650-8659, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39151150

RESUMEN

This work systematically studied thermocatalytic and photocatalytic pathways of formaldehyde degradation and H-assisted O2 reduction over a Pt13/anatase-TiO2(101) composite via DFT calculations together with constrained molecular dynamics (MD) simulations. We show that photocatalytic O2 reduction on Pt/TiO2 can directly generate •OH radicals (*O2 → *OOH → •OH) via two hydrogenation steps with small barriers, and the product selectivity (*H2O2 or •OH) is decided by the relative position between catalyst Fermi level and •OH/*H2O2 redox potential (theoretical determination of 0.07 V referencing to the SHE). Such a novel reaction channel was furthermore validated at the liquid-solid interface via constrained MD simulations and experimental electron paramagnetic resonance detections, and a wide range of H resources, e.g., *HCHO, *HCO, *H (H+ + e-), can always drive the direct •OH generation. The additional portion of e--triggered •OH radicals are prone to diffuse into solution or the TiO2 surface and furthermore cooperate with the conventional h+-driven photooxidations.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39066808

RESUMEN

PURPOSE: The angiotensin converting enzyme 2 (ACE2) plays a regulatory role in the cardiovascular system and serves SARS-CoV-2 as an entry receptor. The aim of this study was to synthesize and evaluate radiofluorinated derivatives of the ACE2 inhibitor MLN-4760. [18F]F-MLN-4760 and [18F]F-Aza-MLN-4760 were demonstrated to be suitable for non-invasive imaging of ACE2, potentially enabling a better understanding of its expression dynamics. METHODS: Computational molecular modeling, based on the structures of human ACE2 (hACE2) and mouse ACE2 (mACE2), revealed that the ACE2-binding modes of F-MLN-4760 and F-Aza-MLN-4760 were similar to that of MLN-4760. Co-crystallization of the hACE2/F-MLN-4760 protein complex was performed for confirmation. Displacement experiments using [3H]MLN-4760 enabled the determination of the binding affinities of the synthesized F-MLN-4760 and F-Aza-MLN-4760 to hACE2 expressed in HEK-ACE2 cells. Aryl trimethylstannane-based and pyridine-based radiofluorination precursors were synthesized and used for the preparation of the respective radiotracers. [18F]F-MLN-4760 and [18F]F-Aza-MLN-4760 were evaluated with regard to the uptake in HEK-ACE2 and HEK-ACE cells and in vitro binding to tissue sections of HEK-ACE2 xenografts and normal organs of mice. Biodistribution and PET/CT imaging studies of [18F]F-MLN-4760 and [18F]F-Aza-MLN-4760 were performed using HEK-ACE2 and HEK-ACE xenografted nude mice. RESULTS: Crystallography data revealed an equal hACE2-binding mode for F-MLN-4760 as previously found for MLN-4760. Moreover, computer-based modeling indicated that similar binding to hACE2 and mACE2 holds true for both, F-MLN-4760 and F-Aza-MLN-4760, as is the case for MLN-4760. The IC50 values were three-fold and seven-fold higher for F-MLN-4760 and F-Aza-MLN-4760, respectively, than for MLN-4760. [18F]F-MLN-4760 and [18F]F-Aza-MLN-4760 were obtained in 1.4 ± 0.3 GBq and 0.5 ± 0.1 GBq activity with > 99% radiochemical purity in a 5.3% and 1.2% radiochemical yield, respectively. Uptake in HEK-ACE2 cells was higher for [18F]F-MLN-4760 (67 ± 9%) than for [18F]F-Aza-MLN-4760 (37 ± 8%) after 3-h incubation while negligible uptake was seen in HEK-ACE cells (< 0.3%). [18F]F-MLN-4760 and [18F]F-Aza-MLN-4760 accumulated specifically in HEK-ACE2 xenografts of mice (13 ± 2% IA/g and 15 ± 2% IA/g at 1 h p.i.) with almost no uptake observed in HEK-ACE xenografts (< 0.3% IA/g). This was confirmed by PET/CT imaging, which also visualized unspecific accumulation in the gall bladder and intestinal tract. CONCLUSION: Both radiotracers showed specific and selective binding to ACE2 in vitro and in vivo. [18F]F-MLN-4760 was, however, obtained in higher yields and the ACE2-binding affinity was superior over that of [18F]F-Aza-MLN-4760. [18F]F-MLN-4760 would, thus, be the candidate of choice for further development in view of its use for PET imaging of ACE2.

3.
FEBS Lett ; 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38946058

RESUMEN

Glycosylase base editor (GBE) can induce C-to-G transversion in mammalian cells, showing great promise for the treatment of human genetic disorders. However, the limited efficiency of transversion and the possibility of off-target effects caused by Cas9 restrict its potential clinical applications. In our recent study, we have successfully developed TaC9-CBE and TaC9-ABE by separating nCas9 and deaminase, which eliminates the Cas9-dependent DNA off-target effects without compromising editing efficiency. We developed a novel GBE called TaC9-GBEYE1, which utilizes the deaminase and UNG-nCas9 guided by TALE and sgRNA, respectively. TaC9-GBEYE1 showed comparable levels of on-target editing efficiency to traditional GBE at 19 target sites, without any off-target effects caused by Cas9 or TALE. The TaC9-GBEYE1 is a safe tool for gene therapy.

4.
Nat Commun ; 15(1): 6255, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048547

RESUMEN

Evolution of SARS-CoV-2 variants emphasizes the need for multivalent vaccines capable of simultaneously targeting multiple strains. SCTV01E is a tetravalent COVID-19 vaccine derived from the spike protein of SARS-CoV-2 variants Alpha, Beta, Delta, and Omicron BA.1. In this double-blinded placebo-controlled pivotal efficacy trial (NCT05308576), the primary endpoint was vaccine efficacy (VE) against COVID-19 seven days post-vaccination in individuals without recent infection. Other endpoints included evaluating safety, immunogenicity, and the VE against all SARS-CoV-2 infections in individuals meeting the study criteria. Between December 26, 2022, and January 15, 2023, 9,223 individuals were randomized at a 1:1 ratio to receive SCTV01E or a placebo. SCTV01E showed a VE of 69.4% (95% CI: 50.6, 81.0) 7 days post-vaccination, with 75 cases in the placebo group and 23 in the SCTV01E group for the primary endpoint. VEs were 79.7% (95% CI: 51.0, 91.6) and 82.4% (95% CI: 57.9, 92.6), respectively, for preventing symptomatic infection and all SARS-CoV-2 infections 14 days post-vaccination. SCTV01E elicited a 25.0-fold higher neutralizing antibody response against Omicron BA.5 28 days post-vaccination compared to placebo. Reactogenicity was generally mild and transient, with no reported vaccine-related SAE, adverse events of special interest (AESI), or deaths. The trial aligned with the shift from dominant variants BA.5 and BF.7 to XBB, suggesting SCTV01E as a potential vaccine alternative effective against present and future variants.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Eficacia de las Vacunas , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Método Doble Ciego , Femenino , Masculino , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , SARS-CoV-2/inmunología , Adulto , Persona de Mediana Edad , Anticuerpos Antivirales/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/inmunología , Anciano , Adulto Joven , Inmunogenicidad Vacunal , Adolescente , Vacunación/métodos
5.
Animals (Basel) ; 14(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39061513

RESUMEN

As a transcription factor, Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) binds to downstream target genes to participate in cell proliferation and cell differentiation. We found that the NR4A1 reached the highest expression at 60 h after the differentiation of goat intramuscular preadipocytes. Overexpression of goat NR4A1 increased the number of intracellular lipid droplets and up-regulated the expression of adipocyte-differentiation-related marker genes including AP2, SREBP1, ACC, GPAM, and DGAT2, while the relative expression levels of Pref-1 and HSL were significantly decreased. On the contrary, after NR4A1 was knocked down by siRNA, the number of intracellular lipid droplets and the relative expression levels of LPL, CEBPα, CEBPß, ACC, and DGAT2 were significantly decreased, and the relative expression levels of Pref-1 and HSL were significantly up-regulated. These results suggest that NR4A1 promotes the differentiation of goat intramuscular preadipocytes. Transcriptome sequencing was carried out after overexpression of goat NR4A1, and the KEGG enrichment analysis result showed that the most differentially expressed genes were related to adipocyte differentiation and were enriched in the PI3K-Akt signaling pathway. LY249002, an inhibitor of the PI3K-Akt signaling pathway, was introduced and decreased the number of intracellular lipid droplets, and the relative expression levels of C/EBPα, SREBP1, AP2, C/EBPß, GPAM, ACC, DGAT1, DGAT2, and ATGL were decreased accordingly. The above results indicate that overexpression of goat NR4A1 may promote the differentiation of intramuscular preadipocytes through the PI3K-Akt signaling pathway.

6.
Front Med (Lausanne) ; 11: 1417611, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39005658

RESUMEN

Hemochromatosis, also known as siderosis, is a disease caused by excessive iron deposition in human organs and tissues, resulting from iron metabolism disorders. It is clinically characterized by skin pigmentation (bronze color), liver cirrhosis, diabetes, weakness, and fatigue. Additional symptoms may include arthritis, hypothyroidism, heart failure, and sexual hypofunction. Clinical manifestations can vary from person to person, with a few patients showing no clinical manifestations, which makes the diagnosis difficult for clinicians. In this case report, we described hereditary hemochromatosis related to a mutation in the HAMP gene in Fuyang City, China, as a reference for clinicians. Hereditary hemochromatosis is rarely reported in China. Clinicians in China have relatively insufficient knowledge of this disease, which leads to frequent misdiagnosis. In this case report, we describe hereditary hemochromatosis related to HAMP gene mutation in Fuyang City, China, for the clinician's reference.

7.
Med Sci Monit ; 30: e943937, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38978275

RESUMEN

BACKGROUND Spontaneous intracerebral hemorrhage has a high fatality rate within the initial month after onset. This study determined the safety and therapeutic efficacy of minimally invasive puncture for supra-tentorial intracranial hematoma under C-arm computed tomography (CT) 4-dimensional navigation. MATERIAL AND METHODS We retrospectively analyzed 64 patients with supra-tentorial cerebral hemorrhage from June 2020 to May 2023; 31 patients were assigned to the study group (C-arm CT navigation puncture) and 33 patients were in the control group (conventional CT-guided puncture). The analysis focused on assessment of puncture error, postoperative complication rate, and the Glasgow Outcome Scale (GOS) and National Institute of Health Stroke Scale (NIHSS) scores 30 and 90 days after surgery. RESULTS C-arm CT navigation puncture had improved precision, with significantly reduced transverse (3.17±1.75 mm) and longitudinal (1.83±1.21 mm) deviations, compared with the control group (7.88±1.74 mm and 5.50±1.84 mm, respectively; P<0.05). The overall postoperative complication rate was significantly lower in the study group than in the control group (12.90% vs 36.36%, P<0.05). The mean GOS score was higher in the study group than in the control group 30 and 90 days postoperatively (3.42±0.96 and 3.97±0.95 vs 2.94±0.79 and 3.46±0.90, respectively; P<0.05), while the mean NIHSS score was lower in the study group than in the control group 30 and 90 days postoperatively (10.58±6.52 and 5.97±4.55 vs 14.42±8.13 and 9.55±8.31, respectively; P<0.05). CONCLUSIONS Supra-tentorial intracranial hematoma puncture under C-arm CT 4-dimensional navigation is accurate, safe, and beneficial.


Asunto(s)
Punciones , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Punciones/métodos , Punciones/efectos adversos , Anciano , Hematoma , Hemorragia Cerebral/diagnóstico por imagen , Complicaciones Posoperatorias , Adulto , Resultado del Tratamiento
8.
Int J Pharm ; 661: 124426, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38972519

RESUMEN

In recent years, the use of arsenic trioxide (ATO) in the context of ovarian cancer chemotherapy has attracted significant attention. However, ATO's limited biocompatibility and the occurrence of severe toxic side effects hinder its clinical application. A nanoparticle (NP) drug delivery system using ATO as a therapeutic agent is reported in this study. Achieving a synergistic effect by combining starvation therapy, chemodynamic therapy, and chemotherapy for the treatment of ovarian cancer was the ultimate goal of this system. This nanotechnology-based drug delivery system (NDDS) introduced arsenic-manganese complexes into cancer cells, leading to the subsequent release of lethal arsenic ions (As3+) and manganese ions (Mn2+). The acidic microenvironment of the tumor facilitated this process, and MR imaging offered real-time monitoring of the ATO dose distribution. Simultaneously, to produce reactive oxygen species that induced cell death through a Fenton-like reaction, Mn2+ exploited the surplus of hydrogen peroxide (H2O2) within tumor cells. Glucose oxidase-based starvation therapy further supported this mechanism, which restored H2O2 and lowered the cellular acidity. Consequently, this approach achieved self-enhanced chemodynamic therapy. Homologous targeting of the NPs was facilitated through the use of SKOV3 cell membranes that encapsulated the NPs. Hence, the use of a multimodal NDDS that integrated ATO delivery, therapy, and monitoring exhibited superior efficacy and biocompatibility compared with the nonspecific administration of ATO. This approach presents a novel concept for the diagnosis and treatment of ovarian cancer.


Asunto(s)
Antineoplásicos , Trióxido de Arsénico , Nanopartículas , Neoplasias Ováricas , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Humanos , Concentración de Iones de Hidrógeno , Línea Celular Tumoral , Trióxido de Arsénico/administración & dosificación , Trióxido de Arsénico/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Nanopartículas/química , Manganeso/química , Manganeso/administración & dosificación , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno/metabolismo , Ratones , Materiales Biomiméticos/química , Materiales Biomiméticos/administración & dosificación , Ratones Desnudos , Sistemas de Liberación de Medicamentos/métodos , Sistema de Administración de Fármacos con Nanopartículas/química , Glucosa Oxidasa/administración & dosificación , Ratones Endogámicos BALB C
9.
Math Biosci Eng ; 21(4): 5068-5091, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38872527

RESUMEN

In this paper, the dynamic behaviors and control strategies of a rumor propagation model are studied in multi-lingual environment. First, an S2E2I2R rumor propagation model is proposed, which incorporates a non-smooth inhibition mechanism. Meanwhile, the existence and stability of the equilibrium are analyzed, grounded in the spreader threshold of the government intervention. Finally, the optimal control and the event-triggered impulsive control strategies are proposed to mitigate the spread of rumors, and the comparison of their effectiveness is further presented by the numerical simulation and a practical case.

10.
Biotechnol Bioeng ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923503

RESUMEN

Spinal muscular atrophy (SMA) is a devastating neuromuscular disease caused by mutations in the survival motor neuron 1 (SMN1) gene. Gene editing technology repairs the conversion of the 6th base T to C in exon 7 of the paralogous SMN2 gene, compensating for the SMN protein expression and promoting the survival and function of motor neurons. However, low editing efficiency and unintended off-target effects limit the application of this technology. Here, we optimized a TaC9-adenine base editor (ABE) system by combining Cas9 nickase with the transcription activator-like effector (TALE)-adenosine deaminase fusion protein to effectively and precisely edit SMN2 without detectable Cas9 dependent off-target effects in human cell lines. We also generated human SMA-induced pluripotent stem cells (SMA-iPSCs) through the mutation of the splice acceptor or deletion of the exon 7 of SMN1. TaC9-R10 induced 45% SMN2 T6 > C conversion in the SMA-iPSCs. The SMN2 T6 > C splice-corrected SMA-iPSCs were directionally differentiated into motor neurons, exhibiting SMN protein recovery and antiapoptosis ability. Therefore, the TaC9-ABE system with dual guides from the combination of Cas9 with TALE could be a potential therapeutic strategy for SMA with high efficacy and safety.

11.
Acad Radiol ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693026

RESUMEN

RATIONALE AND OBJECTIVES: To develop and validate a predictive model for osteoporosis and osteopenia prediction by fusing deep transfer learning (DTL) features and classical radiomics features based on single-source dual-energy computed tomography (CT) virtual monochromatic imaging. METHODS: A total of 606 lumbar vertebrae with dual-energy CT imaging and quantitative CT (QCT) evaluation were included in the retrospective study and randomly divided into the training (n = 424) and validation (n = 182) cohorts. Radiomics features and DTL features were extracted from 70-keV monochromatic CT images, followed by feature selection and model construction, radiomics and DTL features models were established. Then, we integrated the selected two types of features into a features fusion model. We developed a two-level classifier for the hierarchical pairwise classification of each vertebra. All the vertebrae were first classified into osteoporosis and non-osteoporosis groups, then non-osteoporosis group was classified into osteopenia and normal groups. QCT was used as reference. The predictive performance and clinical usefulness of three models were evaluated and compared. RESULTS: The area under the curve (AUC) of the features fusion, radiomics and DTL models for the classification between osteoporosis and non-osteoporosis were 0.981, 0.999, 0.997 in the training cohort and 0.979, 0.943, 0.848 in the validation cohort. Furthermore, the AUCs of the previously mentioned models for the differentiation between osteopenia and normal were 0.994, 0.971, 0.996 in the training cohort and 0.990, 0.968, 0.908 in the validation cohort. The overall accuracy of the previously mentioned models for two-level classifications was 0.979, 0.955, 0.908 in the training cohort and 0.918, 0.885, 0.841 in the validation cohort. Decision curve analysis showed that all models had high clinical value. CONCLUSION: The feature fusion model can be used for osteoporosis and osteopenia prediction with improved predictive ability over a radiomics model or a DTL model alone.

12.
Inorg Chem ; 63(20): 9058-9065, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38720438

RESUMEN

Nitrofurans are important synthetic broad-spectrum antibacterial drugs with the basic structure of 5-nitrofuran. Due to their toxicity, it is essential to develop a sensitive sensor with strong anti-interference capabilities for their detection. In this work, two {P4Mo6O31}12--based compounds, [H4(HPTTP)]2{CuI[Mo12O24(OH)6(PO4)3(HPO4)(H2PO4)4]}·xH2O (x = 13 for (1), 7 for (2); HPTTP = 4,4',4″,4‴-(1H-pyrrole-2,3,4,5-tetrayl)tetrapyridine), exhibiting similar coordination but distinct stacking modes. Both compounds were synthesized and used for the electrochemical detection of nitrofuran antibiotics. The tetrapyridine-based ligand was generated in situ during assembly, and its potential mechanism was discussed. Composite electrode materials, formed by mixing graphite powder with compounds 1-2 and physically grinding them, proved to be highly effective in the electrochemical trace detection of furazolidone (FZD) and furaltadone hydrochloride (FTD·HCl) under optimal conditions. Besides, the possible electrochemical detection mechanisms of two nitro-antibiotics were studied.


Asunto(s)
Antibacterianos , Complejos de Coordinación , Cobre , Nitrofuranos , Polímeros , Antibacterianos/química , Antibacterianos/análisis , Ligandos , Nitrofuranos/análisis , Nitrofuranos/química , Cobre/química , Cobre/análisis , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Polímeros/química , Molibdeno/química , Piridinas/química , Estructura Molecular , Técnicas Electroquímicas , Modelos Moleculares
13.
Mikrochim Acta ; 191(6): 303, 2024 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709340

RESUMEN

A platform was designed based on Fe3O4 and CsPbBr3@SiO2 for integrated magnetic enrichment-fluorescence detection of Salmonella typhimurium, which significantly simplifies the detection process and enhances the working efficiency. Fe3O4 served as a magnetic enrichment unit for the capture of S. typhimurium. CsPbBr3@SiO2 was employed as a fluorescence-sensing unit for quantitative signal output, where SiO2 was introduced to strengthen the stability of CsPbBr3, improve its biomodificability, and prevent lead leakage. More importantly, the SiO2 shell shows neglectable absorption or scattering towards fluorescence, making the CsPbBr3@SiO2 exhibit a high quantum yield of 74.4%. After magnetic enrichment, the decreasing rate of the fluorescence emission intensity of the CsPbBr3@SiO2 supernatant at 527 nm under excitation light at UV 365 nm showed a strong linear correlation with S. typhimurium concentration of 1 × 102~1 × 108 CFU∙mL-1, and the limit of detection (LOD) reached 12.72 CFU∙mL-1. This platform has demonstrated outstanding stability, reproducibility, and resistance to interference, which provides an alternative for convenient and quantitative detection of S. typhimurium.


Asunto(s)
Colorantes Fluorescentes , Límite de Detección , Salmonella typhimurium , Dióxido de Silicio , Salmonella typhimurium/aislamiento & purificación , Dióxido de Silicio/química , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , Plomo/química , Sistemas de Atención de Punto , Sulfuros/química , Nanopartículas de Magnetita/química , Humanos
14.
J Diabetes ; 16(6): e13557, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38751366

RESUMEN

Diabetes mellitus (DM) is a common chronic disease affecting humans globally. It is characterized by abnormally elevated blood glucose levels due to the failure of insulin production or reduction of insulin sensitivity and functionality. Insulin and glucagon-like peptide (GLP)-1 replenishment or improvement of insulin resistance are the two major strategies to treat diabetes. Recently, optogenetics that uses genetically encoded light-sensitive proteins to precisely control cell functions has been regarded as a novel therapeutic strategy for diabetes. Here, we summarize the latest development of optogenetics and its integration with synthetic biology approaches to produce light-responsive cells for insulin/GLP-1 production, amelioration of insulin resistance and neuromodulation of insulin secretion. In addition, we introduce the development of cell encapsulation and delivery methods and smart bioelectronic devices for the in vivo application of optogenetics-based cell therapy in diabetes. The remaining challenges for optogenetics-based cell therapy in the clinical translational study are also discussed.


Asunto(s)
Diabetes Mellitus , Optogenética , Humanos , Optogenética/métodos , Diabetes Mellitus/terapia , Animales , Insulina/metabolismo , Resistencia a la Insulina , Péptido 1 Similar al Glucagón , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Células Secretoras de Insulina/metabolismo
17.
PLoS One ; 19(4): e0298287, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38593135

RESUMEN

Cryo-electron micrograph images have various characteristics such as varying sizes, shapes, and distribution densities of individual particles, severe background noise, high levels of impurities, irregular shapes, blurred edges, and similar color to the background. How to demonstrate good adaptability in the field of image vision by picking up single particles from multiple types of cryo-electron micrographs is currently a challenge in the field of cryo-electron micrographs. This paper combines the characteristics of the MixUp hybrid enhancement algorithm, enhances the image feature information in the pre-processing stage, builds a feature perception network based on the channel self-attention mechanism in the forward network of the Swin Transformer model network, achieving adaptive adjustment of self-attention mechanism between different single particles, increasing the network's tolerance to noise, Incorporating PReLU activation function to enhance information exchange between pixel blocks of different single particles, and combining the Cross-Entropy function with the softmax function to construct a classification network based on Swin Transformer suitable for cryo-electron micrograph single particle detection model (Swin-cryoEM), achieving mixed detection of multiple types of single particles. Swin-cryoEM algorithm can better solve the problem of good adaptability in picking single particles of many types of cryo-electron micrographs, improve the accuracy and generalization ability of the single particle picking method, and provide high-quality data support for the three-dimensional reconstruction of a single particle. In this paper, ablation experiments and comparison experiments were designed to evaluate and compare Swin-cryoEM algorithms in detail and comprehensively on multiple datasets. The Average Precision is an important evaluation index of the evaluation model, and the optimal Average Precision reached 95.5% in the training stage Swin-cryoEM, and the single particle picking performance was also superior in the prediction stage. This model inherits the advantages of the Swin Transformer detection model and is superior to mainstream models such as Faster R-CNN and YOLOv5 in terms of the single particle detection capability of cryo-electron micrographs.


Asunto(s)
Algoritmos , Electrones , Microscopía por Crioelectrón/métodos , Procesamiento de Imagen Asistido por Computador/métodos
18.
Eur J Gastroenterol Hepatol ; 36(6): 758-765, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38683192

RESUMEN

BACKGROUND: Esophageal variceal (EV) hemorrhage is a life-threatening consequence of portal hypertension in hepatitis B virus (HBV) -induced cirrhotic patients. Screening upper endoscopy and endoscopic variceal ligation to find EVs for treatment have complications, contraindications, and high costs. We sought to identify the nomogram models (NMs) as alternative predictions for the risk of EV hemorrhage. METHODS: In this case-control study, we retrospectively analyzed 241 HBV-induced liver cirrhotic patients treated for EVs at the Second People's Hospital of Fuyang City, China from January 2021 to April 2023. We applied univariate analysis and multivariate logistic regression to assess the accuracy of various NMs in EV hemorrhage. The area under the curve (AUC) and calibration curves of the receiver's operating characteristics were used to evaluate the predictive accuracy of the nomogram. Decision curve analysis (DCA) was used to determine the clinically relevant of nomograms. RESULTS: In the prediction group, multivariate logistic regression analysis identified platelet distribution and spleen length as independent risk factors for EVs. We applied NMs as the independent risk factors to predict EVs risk. The NMs fit well with the calibration curve and have good discrimination ability. The AUC and DCA demonstrated that NMs with a good net benefit. The above results were validated in the validation cohort. CONCLUSION: Our non-invasive NMs based on the platelet distribution width and spleen length may be used to predict EV hemorrhage in HBV-induced cirrhotic patients. NMs can help clinicians to increase diagnostic performance leading to improved treatment measures.


Asunto(s)
Várices Esofágicas y Gástricas , Hemorragia Gastrointestinal , Cirrosis Hepática , Nomogramas , Humanos , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/diagnóstico , Cirrosis Hepática/complicaciones , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/diagnóstico , Factores de Riesgo , Estudios de Casos y Controles , Adulto , Medición de Riesgo , Hepatitis B/complicaciones , Curva ROC , Recuento de Plaquetas , Técnicas de Apoyo para la Decisión , Valor Predictivo de las Pruebas , Modelos Logísticos , Bazo/diagnóstico por imagen , Bazo/patología , Tamaño de los Órganos , China/epidemiología
19.
Animals (Basel) ; 14(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38612250

RESUMEN

BACKGROUND: Feline pulmonary Langerhans cells histiocytosis (PLCH) is a rare disorder that results in progressive respiratory failure secondary to pulmonary parenchymal infiltration with Langerhans cells (LCs). A diagnosis of PLCH is proposed based on the clinical features and pathological findings and confirmed based on the infiltrating histiocytic cells. There are few documented cases of feline PLCH, and this case report of PLCH in an African Lion could present new information and aspects of this feline histiocytic disease. CASE PRESENTATION: An African lion at Hohhot Zoo showing severe hyporexia and dyspnea with subsequent mental depression and emaciation died of exhaustion after a 35-day course of illness. Empirical treatment did not have a significant effect. An autopsy revealed that the lungs were enlarged and hardened due to infiltrative lesions, with many yellowish-white foci in all the lobes and sections. Furthermore, the kidneys were atrophied and had scattered grayish-white lesions on the surface. At the same time, congestion was widely distributed in various locations, including the liver, subcutaneous loose connective tissues, serosal surface and other tissues and organs. Histologically, proliferative histiocytic cells (PHCs) were scattered in the alveolar cavities, bronchioles and submucosa of bronchioles, with evident cellular and nuclear pleomorphism, and thus the alveolar septa were obliterated. The histopathological changes in other organs included chronic sclerosing glomerulonephritis, proliferated Kupffer cells in the liver, adrenal edema and interstitial connective tissue hyperplasia, as well as atrophy of the small intestines and spleen. Furthermore, immunohistochemical analysis results were strongly positive for CD1a, vimentin, S100 and E-cadherin in the membrane or cytoplasm of PHCs, supporting an LC phenotype. CONCLUSIONS: Here, we present a rare pulmonary Langerhans cell histiocytosis case in an African lion.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38624164

RESUMEN

Combined mild-temperature photothermal/chemotherapy has emerged as a highly promising modality for tumor therapy. However, its therapeutic efficacy is drastically compromised by the heat-induced overexpression of heat shock proteins (HSPs) by the cells, which resist heat stress and apoptosis. The purpose of this study was to downregulate HSPs and enhance the mild-temperature photothermal/chemotherapy effect. In detail, the colon cancer cell membrane (CT26M)-camouflaged HSP90 inhibitor ganetespib and the chemotherapeutic agent doxorubicin (DOX)-coloaded hollow mesoporous Prussian blue (HMPB) nanoplatform (named PGDM) were designed for synergistic mild photothermal/chemotherapy via HSP inhibition. In addition to being a photothermal agent with a high efficiency of photothermal conversion (24.13%), HMPB offers a hollow hole that can be filled with drugs. Concurrently, the cancer cell membrane camouflaging enhances tumor accumulation through a homologous targeting mechanism and gives the nanoplatform the potential to evade the immune system. When exposed to NIR radiation, HMPB's photothermal action (44 °C) not only causes tumor cells to undergo apoptosis but also causes ganetespib to be released on demand. This inhibits the formation of HSP90, which enhances the mild photothermal/chemotherapy effect. The results confirmed that the combined treatment regimen of mild photothermal therapy (PTT) and chemotherapy showed a better therapeutic efficacy than the individual treatment methods. Therefore, this multimodal nanoparticle can advance the development of drugs for the treatment of malignancies, such as colon cancer, and has prospects for clinical application.

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