Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 168
Filtrar
1.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39240154

RESUMEN

Pulse generators with high voltage and several nanoseconds of rise time are typically used to carry out the equivalent assessment of the protection performance of typical power equipment in the high-altitude electromagnetic pulse environment. In this paper, a pulse generator with high voltage and fast rise time has been designed, and the diagnostic system with high temporal resolution has been integrated to measure the output pulse voltage of the generator. The experimental results showed that the output pulse voltage of the generator on the output load can reach 645 kV when the charged voltage of Marx generator capacitors is 40 kV. The rise time of the generator is 8.2-9.9 ns when the charged voltage of Marx generator capacitors is in the range of 20-40 kV.

2.
Chin J Nat Med ; 22(8): 746-755, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39197964

RESUMEN

Ischemic stroke (IS) is a globally prevalent cerebrovascular disorder resulting from cerebral vessel occlusion, leading to significant morbidity and mortality. The intricate pathological mechanisms underlying IS complicate the development of effective therapeutic interventions. Ferroptosis, a form of programmed cell death (PCD) characterized by iron overload and accumulation of lipid peroxidation products, has been increasingly recognized as a key contributor to IS pathology. Traditional Chinese medicines (TCMs) have long been utilized in the management of IS, prompting extensive research into their potential as sources of natural ferroptosis inhibitors. This review investigates the critical role of ferroptosis in IS and provides a comprehensive analysis of current research on natural ferroptosis inhibitors identified in TCMs, aiming to lay a theoretical groundwork for the development of innovative anti-IS therapies.


Asunto(s)
Medicamentos Herbarios Chinos , Ferroptosis , Accidente Cerebrovascular Isquémico , Medicina Tradicional China , Ferroptosis/efectos de los fármacos , Humanos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/metabolismo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Animales
3.
Proc Natl Acad Sci U S A ; 121(34): e2400657121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39141344

RESUMEN

Microsporidia are intracellular eukaryotic pathogens that pose a substantial threat to immunocompromised hosts. The way these pathogens manipulate host cells during infection remains poorly understood. Using a proximity biotinylation strategy we established that microsporidian EnP1 is a nucleus-targeted effector that modifies the host cell environment. EnP1's translocation to the host nucleus is meditated by nuclear localization signals (NLSs). In the nucleus, EnP1 interacts with host histone H2B. This interaction disrupts H2B monoubiquitination (H2Bub), subsequently impacting p53 expression. Crucially, this inhibition of p53 weakens its control over the downstream target gene SLC7A11, enhancing the host cell's resilience against ferroptosis during microsporidian infection. This favorable condition promotes the proliferation of microsporidia within the host cell. These findings shed light on the molecular mechanisms by which microsporidia modify their host cells to facilitate their survival.


Asunto(s)
Ferroptosis , Histonas , Microsporidios , Ubiquitinación , Microsporidios/metabolismo , Microsporidios/genética , Histonas/metabolismo , Humanos , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Interacciones Huésped-Patógeno , Animales , Núcleo Celular/metabolismo , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Microsporidiosis/metabolismo
4.
Water Sci Technol ; 90(4): 1267-1279, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39215737

RESUMEN

The study investigates the effect of the oxidant calcium oxide (CaO) on the codigestion of excess sludge (ES) and plant waste (PW) under mesophilic anaerobic conditions to enhance methane production. The findings indicate that CaO significantly elevated methane yield in the codigestion system, with an optimum CaO addition of 6% resulting in a maximum methane production of 461 mL/g volatile solids, which is approximately 1.3 times that of the control group. Mechanistic exploration revealed that CaO facilitated the disintegration of organic matter, enhanced the release of soluble chemical oxygen demand, and increased the concentrations of soluble proteins and polysaccharides within the codigestion substrate. The presence of CaO was conducive to the generation and biological transformation of volatile fatty acids, with a notable accumulation of acetic acid, a smaller carboxylic acid within the VFAs. The proportion of acetate in the CaO-amended group increased to 32.6-36.9%. Enzymatic analysis disclosed that CaO enhanced the activity of hydrolytic and acidogenic enzymes associated with the ES and PW codigestion process but suppressed the activity of coenzyme F420. Moreover, CaO augmented the nutrient load in the fermentation liquid. The study provides an alternative scheme for the efficient resource utilization of ES and PW.


Asunto(s)
Compuestos de Calcio , Óxidos , Aguas del Alcantarillado , Compuestos de Calcio/química , Anaerobiosis , Óxidos/química , Metano/metabolismo , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Ácidos Grasos Volátiles/metabolismo , Análisis de la Demanda Biológica de Oxígeno
5.
J Immunother ; 47(8): 313-322, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39005046

RESUMEN

Tumor immunotherapy has recently gained popularity as a cancer treatment strategy. The molecular mechanism controlling immune infiltration in lung adenocarcinoma (LUAD) cells, however, is not well characterized. Investigating the immune infiltration modulation mechanism in LUAD is crucial. LUAD patient samples were collected, and HES6 expression and immune infiltration level of CD8 + T cells in patient tissues were analyzed. Bioinformatics was utilized to identify binding relationship between E2F1 and HES6, and enrichment pathway of HES6. The binding of E2F1 to HES6 was verified using dual-luciferase and ChIP experiments. HES6 and E2F1 expression in LUAD cells was detected. LUAD cells were co-cultured with CD8 + T cells, and the CD8 + T cell killing level, IFN-γ secretion, and CD8 + T-cell chemotaxis level were measured. Expression of key genes involved in oxidative phosphorylation was detected, and the oxygen consumption rate of LUAD cells was assessed. A mouse model was constructed to assay Ki67 expression and apoptosis in tumor tissue. High expression of HES6 promoted CD8 + T-cell infiltration and enhanced T-cell killing ability through oxidative phosphorylation. Further bioinformatics analysis, molecular experiments, and cell experiments verified that E2F1 negatively regulated HES6 by oxidative phosphorylation, which suppressed CD8 + T-cell immune infiltration. In addition, in vivo assays illustrated that silencing HES6 repressed tumor cell immune evasion. E2F1 inhibited HES6 transcription, thereby mediating oxidative phosphorylation to suppress immune infiltration of CD8 + T cells in LUAD. The biological functions and signaling pathways of these genes were analyzed, which may help to understand the possible mechanisms regulating immune infiltration in LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Linfocitos T CD8-positivos , Factor de Transcripción E2F1 , Neoplasias Pulmonares , Linfocitos Infiltrantes de Tumor , Fosforilación Oxidativa , Humanos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/genética , Animales , Ratones , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Línea Celular Tumoral , Factor de Transcripción E2F1/metabolismo , Transducción de Señal , Regulación Neoplásica de la Expresión Génica , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Microambiente Tumoral/inmunología , Femenino , Masculino
6.
Acta Trop ; 257: 107302, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38959992

RESUMEN

Toxoplasma gondii is an important protozoan pathogen, which can cause severe diseases in the newborns and immunocompromised individuals. Developing an effective vaccine against Toxoplasma infection is a critically important global health priority. Immunofluorescence staining analysis revealed that TgSAG2 and TgSRS2 are membrane associated and displayed on the surface of the parasite. Immunizations with pBud-SAG2, pBud-SRS2 and pBud-SAG2-SRS2 DNA vaccines significantly increased the production of specific IgG antibodies. Immunization with pBud-SAG2-SRS2 elicited cellular immune response with higher concentrations of IFN-γ and IL-4 compared to the control group. Antigen-specific lymphocyte proliferations in the pBud-SRS2 and pBud-SAG2-SRS2 groups were significantly higher compared to that in the control group. Furthermore, 30 % of mice immunized with pBud-SAG2-SRS2 survived after the challenge infection with virulent T. gondii RH tachyzoites. This study revealed that immunization with pBud-SAG2-SRS2 induced potent immune responses, and has the potential as a promising vaccine candidate for the control of T. gondii infection.


Asunto(s)
Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Inmunoglobulina G , Proteínas Protozoarias , Vacunas Antiprotozoos , Toxoplasma , Toxoplasmosis Animal , Vacunas de ADN , Animales , Vacunas de ADN/inmunología , Vacunas de ADN/genética , Vacunas de ADN/administración & dosificación , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Toxoplasma/inmunología , Toxoplasma/genética , Anticuerpos Antiprotozoarios/sangre , Vacunas Antiprotozoos/inmunología , Vacunas Antiprotozoos/administración & dosificación , Vacunas Antiprotozoos/genética , Ratones , Inmunoglobulina G/sangre , Femenino , Toxoplasmosis Animal/prevención & control , Toxoplasmosis Animal/inmunología , Ratones Endogámicos BALB C , Interferón gamma/inmunología , Modelos Animales de Enfermedad , Proliferación Celular , Interleucina-4/inmunología , Análisis de Supervivencia
7.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38995154

RESUMEN

This paper presents three methods aimed at enhancing the flashover voltage of the supporting insulator in a Tesla transformer. These methods include optimizing the maximum electric field on the insulator surface, adjusting the overall structure of the insulator, and changing the surface structure of the insulator. Ten insulator samples with different structures were designed based on electric field simulation. Subsequent experiments were conducted to validate the effectiveness of these methods in improving flashover voltage. On this basis, the supporting insulator of the Tesla transformer was redesigned, leading to an increased output voltage. The results are summarized in the following. First, optimization of the shielding rings of the cathode and anode reduces the electric field at the triple junction, which significantly increases the flashover voltage. Second, extending the inclination starting position of insulators with the same inclination angle effectively reduces the surface electric field intensity and increases the flashover voltage. Third, increasing the inclination angle within a certain range while keeping the inclination starting position constant extends the creepage distance and enhances the flashover voltage. However, excessively large inclination angles may lead to a decrease in flashover voltage due to excessive normal electric field. Fourth, grooving on the insulator surface at appropriate locations can inhibit the development of the streamer and improve flashover voltage. Finally, the supporting insulator of the Tesla transformer was redesigned based on these results, elevating the output voltage from 750 kV to over 1 MV.

8.
Orthop Surg ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39072994

RESUMEN

OBJECTIVE: Treating patients with large thoracic scoliosis (between 70° and 100°) poses technical challenges, particularly with traditional correction techniques (TCT). To address this, we developed a novel deformity correction manipulation system (DCMS) aimed at reducing surgical complexity and trauma. This study aims to assess the safety and effectiveness of DCMS in treating large thoracic scoliosis. METHODS: From January 2016 to June 2021, 76 patients with large thoracic scoliosis were included in this retrospective study. The patients were divided into two groups: DCMS (n = 34) and TCT (n = 42). Basic patient data including age at surgery, sex, etiology, Risser sign, flexibility of the main thoracic curve, instrumented levels, number of screws, duration of hospital stay, and follow-up time were collected and analyzed. Radiographic and clinical outcomes, as measured by various radiographic parameters and Scoliosis Research Society-30 (SRS-30) scores, were retrospectively analyzed and compared between the two groups. Adverse events were also documented. Statistical analyses were performed using two-tailed independent t-tests, chi-square tests, and Fisher's exact test. RESULTS: The DCMS group exhibited significantly shorter operative times, reduced blood loss, and shorter hospital stays compared to the TCT group. However, there were no significant differences between the two groups in terms of age at surgery, sex, etiology, Risser sign, flexibility of the main curve, instrumented levels, number of screws, and follow-up time. While preoperative major curves were statistically similar between the two groups, the DCMS group achieved a superior correction rate compared to the TCT group (74.2% ± 8.8% vs 68.1% ± 10.5%). No significant differences were observed in other radiographic parameters, SRS-30 scores, or the incidence of adverse events. CONCLUSION: The application of DCMS resulted in shorter operative times, reduced blood loss, shorter hospital stays, and greater curve correction compared to TCT. DCMS proves to be a safe and effective technique for treating large thoracic curves.

9.
Br J Haematol ; 205(2): 645-652, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38972835

RESUMEN

This retrospective study analysed 106 acute myeloid leukaemia (AML) patients undergoing autologous haematopoietic stem cell transplantation (ASCT) to assess the impact of multiple small-dose infusions of granulocyte-colony-stimulating factor (G-CSF)-mobilized haploidentical lymphocytes as post-ASCT maintenance therapy. Among them, 50 patients received lymphocyte maintenance therapy, 21 received alternative maintenance therapy, and 35 received no maintenance therapy. Patients receiving lymphocyte maintenance therapy demonstrated significantly higher overall survival (OS) and disease-free survival (DFS) compared to those without maintenance therapy, with 4-year OS and DFS rates notably elevated. While there were no significant differences in recurrence rates among the three groups, lymphocyte maintenance therapy showcased particular benefits for intermediate-risk AML patients, yielding significantly higher OS and DFS rates and lower relapse rates compared to alternative maintenance therapy and no maintenance therapy. The study suggests that multiple small-dose infusions of G-CSF-mobilized haploidentical lymphocytes may offer promising outcomes for AML patients after ASCT, particularly for those classified as intermediate-risk. These findings underscore the potential efficacy of lymphocyte maintenance therapy in reducing disease relapse and improving long-term prognosis in this patient population.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Transfusión de Linfocitos , Humanos , Leucemia Mieloide Aguda/terapia , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Masculino , Femenino , Adulto , Persona de Mediana Edad , Trasplante de Células Madre Hematopoyéticas/métodos , Estudios Retrospectivos , Trasplante Autólogo , Adolescente , Movilización de Célula Madre Hematopoyética/métodos , Adulto Joven , Anciano , Trasplante Haploidéntico/métodos
10.
J Eukaryot Microbiol ; : e13029, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39030770

RESUMEN

Microsporidia are prolific producers of effector molecules, encompassing both proteins and nonproteinaceous effectors, such as toxins, small RNAs, and small peptides. These secreted effectors play a pivotal role in the pathogenicity of microsporidia, enabling them to subvert the host's innate immunity and co-opt metabolic pathways to fuel their own growth and proliferation. However, the genomes of microsporidia, despite falling within the size range of bacteria, exhibit significant reductions in both structural and physiological features, thereby affecting the repertoire of secretory effectors to varying extents. This review focuses on recent advances in understanding how microsporidia modulate host cells through the secretion of effectors, highlighting current challenges and proposed solutions in deciphering the complexities of microsporidial secretory effectors.

11.
Cyborg Bionic Syst ; 5: 0128, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938902

RESUMEN

Brain-inspired navigation technologies combine environmental perception, spatial cognition, and target navigation to create a comprehensive navigation research system. Researchers have used various sensors to gather environmental data and enhance environmental perception using multimodal information fusion. In spatial cognition, a neural network model is used to simulate the navigation mechanism of the animal brain and to construct an environmental cognition map. However, existing models face challenges in achieving high navigation success rate and efficiency. In addition, the limited incorporation of navigation mechanisms borrowed from animal brains necessitates further exploration. On the basis of the brain-inspired navigation process, this paper launched a systematic study on brain-inspired environment perception, brain-inspired spatial cognition, and goal-based navigation in brain-inspired navigation, which provides a new classification of brain-inspired cognition and navigation techniques and a theoretical basis for subsequent experimental studies. In the future, brain-inspired navigation technology should learn from more perfect brain-inspired mechanisms to improve its generalization ability and be simultaneously applied to large-scale distributed intelligent body cluster navigation. The multidisciplinary nature of brain-inspired navigation technology presents challenges, and multidisciplinary scholars must cooperate to promote the development of this technology.

12.
Cell Res ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898113

RESUMEN

The shift of carbon utilization from primarily glucose to other nutrients is a fundamental metabolic adaptation to cope with decreased blood glucose levels and the consequent decline in glucose oxidation. AMP-activated protein kinase (AMPK) plays crucial roles in this metabolic adaptation. However, the underlying mechanism is not fully understood. Here, we show that PDZ domain containing 8 (PDZD8), which we identify as a new substrate of AMPK activated in low glucose, is required for the low glucose-promoted glutaminolysis. AMPK phosphorylates PDZD8 at threonine 527 (T527) and promotes the interaction of PDZD8 with and activation of glutaminase 1 (GLS1), a rate-limiting enzyme of glutaminolysis. In vivo, the AMPK-PDZD8-GLS1 axis is required for the enhancement of glutaminolysis as tested in the skeletal muscle tissues, which occurs earlier than the increase in fatty acid utilization during fasting. The enhanced glutaminolysis is also observed in macrophages in low glucose or under acute lipopolysaccharide (LPS) treatment. Consistent with a requirement of heightened glutaminolysis, the PDZD8-T527A mutation dampens the secretion of pro-inflammatory cytokines in macrophages in mice treated with LPS. Together, we have revealed an AMPK-PDZD8-GLS1 axis that promotes glutaminolysis ahead of increased fatty acid utilization under glucose shortage.

14.
Front Oncol ; 14: 1254705, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601757

RESUMEN

In the field of medical image segmentation, achieving fast and accurate semantic segmentation of tumor cell nuclei and skin lesions is of significant importance. However, the considerable variations in skin lesion forms and cell types pose challenges to attaining high network accuracy and robustness. Additionally, as network depth increases, the growing parameter size and computational complexity make practical implementation difficult. To address these issues, this paper proposes MD-UNet, a fast cell nucleus segmentation network that integrates Tokenized Multi-Layer Perceptron modules, attention mechanisms, and Inception structures. Firstly, tokenized MLP modules are employed to label and project convolutional features, reducing computational complexity. Secondly, the paper introduces Depthwise Attention blocks and Multi-layer Feature Extraction modules. The Depthwise Attention blocks eliminate irrelevant and noisy responses from coarse-scale extracted information, serving as alternatives to skip connections in the UNet architecture. The Multi-layer Feature Extraction modules capture a wider range of high-level and low-level semantic features during decoding and facilitate feature fusion. The proposed MD-UNet approach is evaluated on two datasets: the International Skin Imaging Collaboration (ISIC2018) dataset and the PanNuke dataset. The experimental results demonstrate that MD-UNet achieves the best performance on both datasets.

15.
Sci Rep ; 14(1): 9269, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38649378

RESUMEN

Rainwater is the main water source in arid and semiarid areas of the Loess Plateau, where rainfall is generally insufficient, ineffective and underutilized during the growing season. Thus, improving rainwater utilization efficiency is essential for sustainable agricultural development. A new system composed of rainwater harvesting, an infiltrator bucket with multiple holes and mulching (RHM), was designed to maintain soil moisture at a proper level in rain-fed orchards in arid and semiarid areas of the Loess Region of China. However, there is a lack of clarity on the effectiveness of RHM. In this study, changes in the soil environment and the growth and physiology of apricot trees were monitored via two treatments: (1) Rain-harvesting irrigation system (RHM) treatment and (2) traditional orchard treatment (CK) as a baseline. The results showed that (1) RHM could effectively improve soil water storage at depths of 0-45 cm and at a horizontal distance of 40 cm from the trunk. For the 1.4 mm light rain event, the soil water content increased by 6.3-12%, and for the two moderate rains, the soil water content increased by 12-25%. The change in the soil relative water content predicted by the LSTM model is consistent with the overall trend of the measured value and gradually decreases, and the prediction accuracy is high, with an error of 0.65. (2) The average soil temperatures at 5 cm, 20 cm and 40 cm under RHM were 17.0% (2.4 °C), 13.6% (1.9 °C) and 7.5% (1 °C) greater than those under CK, respectively. (3) Compared with the control treatment, RHM improved the growth and WUEL of apricot trees. The results highlighted the efficiency of the RHM system in enhancing the soil environment and regulating the growth and physiology of apricot trees, which has greater popularization value in arid and semiarid areas.

16.
Brain ; 147(5): 1644-1652, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38428032

RESUMEN

The pathological misfolding and aggregation of soluble α-synuclein into toxic oligomers and insoluble amyloid fibrils causes Parkinson's disease, a progressive age-related neurodegenerative disease for which there is no cure. HET-s is a soluble fungal protein that can form assembled amyloid fibrils in its prion state. We engineered HET-s(218-298) to form four different fibrillar vaccine candidates, each displaying a specific conformational epitope present on the surface of α-synuclein fibrils. Vaccination with these four vaccine candidates prolonged the survival of immunized TgM83+/- mice challenged with α-synuclein fibrils by 8% when injected into the brain to model brain-first Parkinson's disease or by 21% and 22% when injected into the peritoneum or gut wall, respectively, to model body-first Parkinson's disease. Antibodies from fully immunized mice recognized α-synuclein fibrils and brain homogenates from patients with Parkinson's disease, dementia with Lewy bodies and multiple system atrophy. Conformation-specific vaccines that mimic epitopes present only on the surface of pathological fibrils but not on soluble monomers, hold great promise for protection against Parkinson's disease, related synucleinopathies and other amyloidogenic protein misfolding disorders.


Asunto(s)
Ratones Transgénicos , Enfermedad de Parkinson , alfa-Sinucleína , Animales , Enfermedad de Parkinson/inmunología , Enfermedad de Parkinson/patología , Ratones , alfa-Sinucleína/inmunología , alfa-Sinucleína/metabolismo , Humanos , Amiloide/inmunología , Amiloide/metabolismo , Vacunación , Proteínas Fúngicas/inmunología , Encéfalo/patología , Encéfalo/metabolismo , Encéfalo/inmunología , Femenino , Ratones Endogámicos C57BL
17.
J Invertebr Pathol ; 204: 108091, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38462166

RESUMEN

Ameson portunus is an intracellular pathogen that infects marine crabs Portunus trituberculatus and Scylla paramamosain, causing significant economic losses. However, research into this important parasite has been limited due to the absence of an in vitro culture system. To address this challenge, we developed an in vitro cultivation model of A. portunus using RK13 cell line in this study. The fluorescent labeling assay indicated a high infection rate (∼60 %) on the first day post-infection and quantitative PCR (qPCR) detection demonstrated successful infection as early as six hours post-inoculation. Fluorescence in situ hybridization (FISH) and qPCR were used for the detection of A. portunus infected cells. The FISH probe we designed allowed detection of A. portunus in infected cells and qPCR assay provided accurate quantification of A. portunus in the samples. Transmission electron microscopy (TEM) images revealed that A. portunus could complete its entire life cycle and produce mature spores in RK13 cells. Additionally, we have identified novel life cycle characteristics during the development of A. portunus in RK 13 cells using TEM. These findings contribute to our understanding of new life cycle pathways of A. portunus. The establishment of an in vitro culture model for A. portunus is critical as it provides a valuable tool for understanding the molecular and immunological events that occur during infection. Furthermore, it will facilitate the development of effective treatment strategies for this intracellular pathogen.


Asunto(s)
Braquiuros , Microsporidios , Animales , Microsporidios/fisiología , Microsporidios/genética , Braquiuros/parasitología , Braquiuros/microbiología , Línea Celular , Hibridación Fluorescente in Situ
18.
Acta Psychol (Amst) ; 245: 104233, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38522350

RESUMEN

Online learning has become increasingly prevalent in the era of digitalization, impacted by both internet penetration and the COVID-19 pandemic. Classroom interaction, as a key factor in evaluating students' learning experience in online settings, has been identified to be associated with their academic achievement. While previous research has underscored the significance of classroom interaction in language learning settings, there is relatively limited research on its relationships with student satisfaction and learning. This research intends to explore classroom interaction and its mediating role in the correlation between student satisfaction and perceived online learning in online contexts. Given this, the paper reports a quantitative-method study that examined how Chinese EFL tertiary students perceived three types of classroom interaction (i.e., learner-learner, learner-instructor, and learner-content), their satisfaction, and its influences on their perceived online learning. Data was collected from 319 Chinese university students through convenience sampling and a self-designed questionnaire, and then analyzed with the help of SPSS. The results showed that: 1) the students had moderately positive perceptions of classroom interaction and online learning, but were neutral about their satisfaction; 2) positive correlations were observed between classroom interaction, student satisfaction, and online learning; and 3) student satisfaction predicted perceived online learning, with classroom interaction partially mediating this relationship. The findings of this research have implications for strengthening the effectiveness of online language teaching in the post-COVID-19 era.


Asunto(s)
COVID-19 , Educación a Distancia , Humanos , Pandemias , Estudiantes , Lenguaje
19.
Parasit Vectors ; 17(1): 59, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341599

RESUMEN

BACKGROUND: Toxoplasma gondii is an important protozoan pathogen with medical and veterinary importance worldwide. Drugs currently used for treatment of toxoplasmosis are less effective and sometimes cause serious side effects. There is an urgent need for the development of more effective drugs with relatively low toxicity. METHODS: The effect of tylosin on the viability of host cells was measured using CCK8 assays. To assess the inhibition of tylosin on T. gondii proliferation, a real-time PCR targeting the B1 gene was developed for T. gondii detection and quantification. Total RNA was extracted from parasites treated with tylosin and then subjected to transcriptome analysis by RNA sequencing (RNA-seq). Finally, murine infection models of toxoplasmosis were used to evaluate the protective efficacy of tylosin against T. gondii virulent RH strain or avirulent ME49 strain. RESULTS: We found that tylosin displayed low host toxicity, and its 50% inhibitory concentration was 175.3 µM. Tylsoin also inhibited intracellular T. gondii tachyzoite proliferation, with a 50% effective concentration of 9.759 µM. Transcriptome analysis showed that tylosin remarkably perturbed the gene expression of T. gondii, and genes involved in "ribosome biogenesis (GO:0042254)" and "ribosome (GO:0005840)" were significantly dys-regulated. In a murine model, tylosin treatment alone (100 mg/kg, i.p.) or in combination with sulfadiazine sodium (200 mg/kg, i.g.) significantly prolonged the survival time and raised the survival rate of animals infected with T. gondii virulent RH or avirulent ME49 strain. Meanwhile, treatment with tylosin significantly decreased the parasite burdens in multiple organs and decreased the spleen index of mice with acute toxoplasmosis. CONCLUSIONS: Our findings suggest that tylosin exhibited potency against T. gondii both in vitro and in vivo, which offers promise for treatment of human toxoplasmosis.


Asunto(s)
Toxoplasma , Toxoplasmosis , Humanos , Animales , Ratones , Tilosina/farmacología , Tilosina/uso terapéutico , Toxoplasmosis/tratamiento farmacológico , Toxoplasmosis/parasitología , Sulfadiazina/farmacología , Sulfadiazina/uso terapéutico , Bazo
20.
Food Res Int ; 179: 114021, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342541

RESUMEN

Sheep milk is rich in fat, protein, vitamins and minerals and is also one of the most important sources of natural bioactives. Several biopeptides in sheep milk have been reported to possess antibacterial, antiviral and anti-inflammatory properties, and they may prevent type 2 diabetes (T2D), disease and cancer. However, the precise mechanism(s) underlying the protective role of sheep milk against T2D development remains unclear. Therefore, in the current study, we investigated the effect of sheep milk on insulin resistance and glucose intolerance in high-fat diet (HFD)-fed mice, by conducting intraperitoneal glucose tolerance tests, metabolic cage studies, genomic sequencing, polymerase chain reaction, and biochemical assays. Hyperinsulinemic-euglycemic clamp-based experiments revealed that mice consuming sheep milk exhibited lower hepatic glucose production than mice in the control group. These findings further elucidate the mechanism by which dietary supplementation with sheep milk alleviates HFD-induced systemic glucose intolerance.


Asunto(s)
Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Resistencia a la Insulina , Ovinos , Ratones , Animales , Dieta Alta en Grasa/efectos adversos , Intolerancia a la Glucosa/metabolismo , Intolerancia a la Glucosa/prevención & control , Diabetes Mellitus Tipo 2/prevención & control , Leche/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA