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1.
Bull Math Biol ; 86(5): 49, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558267

RESUMO

This study addresses COVID-19 testing as a nonlinear sampling problem, aiming to uncover the dependence of the true infection count in the population on COVID-19 testing metrics such as testing volume and positivity rates. Employing an artificial neural network, we explore the relationship among daily confirmed case counts, testing data, population statistics, and the actual daily case count. The trained artificial neural network undergoes testing in in-sample, out-of-sample, and several hypothetical scenarios. A substantial focus of this paper lies in the estimation of the daily true case count, which serves as the output set of our training process. To achieve this, we implement a regularized backcasting technique that utilize death counts and the infection fatality ratio (IFR), as the death statistics and serological surveys (providing the IFR) as more reliable COVID-19 data sources. Addressing the impact of factors such as age distribution, vaccination, and emerging variants on the IFR time series is a pivotal aspect of our analysis. We expect our study to enhance our understanding of the genuine implications of the COVID-19 pandemic, subsequently benefiting mitigation strategies.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Pandemias , Modelos Biológicos , Conceitos Matemáticos , Redes Neurais de Computação
2.
Bioresour Technol ; 400: 130683, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599352

RESUMO

The productivity and efficiency of two-chamber microbial electrolysis cell and anaerobic digestion integrated system (MEC-AD) were promoted by a complex of anaerobic granular sludge and iron oxides (Fe-AnGS) as inoculum. Results showed that MEC-AD with Fe-AnGS achieved biogas upgrading with a 23%-29% increase in the energy recovery rate of external circuit current and a 26%-31% decrease in volatile fatty acids. The energy recovery rate of MEC-AD remained at 52%-57%, indicating a stable operation performance. The selectively enriched methanogens and electroactive bacteria resulted in dominant hydrogenotrophic and acetoclastic methanogenesis in the cathode and anode chambers. Mechanistic analysis revealed that MEC-AD with Fe-AnGS led to specifically upregulated enzymes related to energy metabolism and electron transfer. Fe-AnGS as inoculum could improve the long-term operation performance of MEC-AD. Consequently, this study provides an efficient strategy for biogas upgrading in MEC-AD.

3.
Plant Physiol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652695

RESUMO

Centromeres in most multicellular eukaryotes are composed of long arrays of repetitive DNA sequences. Interestingly, several transposable elements, including the well-known long terminal repeat (LTR) retrotransposon CRM (centromeric retrotransposon of maize), were found to be enriched in functional centromeres marked by the centromeric histone H3 (CENH3). Here we report a centromeric long interspersed nuclear element (LINE), Celine, in Populus species. Celine has colonized preferentially in the CENH3-associated chromatin of every poplar chromosome, with 84% of the Celine elements localized in the CENH3-binding domains. By contrast, only 51% of the CRM elements were bound to CENH3 domains in Populus trichocarpa. These results suggest different centromere targeting mechanisms employed by Celine and CRM elements. Nevertheless, the high target specificity seems to be detrimental to further amplification of the Celine elements, leading to a shorter life span and patchy distribution among plant species compared to the CRM elements. Using a phylogenetically guided approach we were able to identify Celine-like LINE elements in tea plant (Camellia sinensis) and green ash tree (Fraxinus pennsylvanica). The centromeric localization of these Celine-like LINEs was confirmed in both species. We demonstrate that the centromere targeting property of Celine-like LINEs is of primitive origin and has been conserved among distantly related plant species.

4.
Neural Netw ; 175: 106296, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38653077

RESUMO

Structural magnetic resonance imaging (sMRI) has shown great clinical value and has been widely used in deep learning (DL) based computer-aided brain disease diagnosis. Previous DL-based approaches focused on local shapes and textures in brain sMRI that may be significant only within a particular domain. The learned representations are likely to contain spurious information and have poor generalization ability in other diseases and datasets. To facilitate capturing meaningful and robust features, it is necessary to first comprehensively understand the intrinsic pattern of the brain that is not restricted within a single data/task domain. Considering that the brain is a complex connectome of interlinked neurons, the connectional properties in the brain have strong biological significance, which is shared across multiple domains and covers most pathological information. In this work, we propose a connectional style contextual representation learning model (CS-CRL) to capture the intrinsic pattern of the brain, used for multiple brain disease diagnosis. Specifically, it has a vision transformer (ViT) encoder and leverages mask reconstruction as the proxy task and Gram matrices to guide the representation of connectional information. It facilitates the capture of global context and the aggregation of features with biological plausibility. The results indicate that CS-CRL achieves superior accuracy in multiple brain disease diagnosis tasks across six datasets and three diseases and outperforms state-of-the-art models. Furthermore, we demonstrate that CS-CRL captures more brain-network-like properties, and better aggregates features, is easier to optimize, and is more robust to noise, which explains its superiority in theory.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38640094

RESUMO

Morin, a naturally occurring bioactive compound shows great potential as an antioxidant, anti-inflammatory agent, and regulator of blood glucose levels. However, its low water solubility, poor lipid solubility, limited bioavailability, and rapid clearance in vivo hinder its application in blood glucose regulation. To address these limitations, we report an enzymatically synthesized nanosized morin particle (MNs) encapsulated in sodium alginate microgels (M@SA). This approach significantly enhances morin's delivery efficiency and therapeutic efficacy in blood glucose regulation. Utilizing horseradish peroxidase, we synthesized MNs averaging 305.7 ± 88.7 nm in size. These MNs were then encapsulated via electrohydrodynamic microdroplet spraying to form M@SA microgels. In vivo studies revealed that M@SA microgels demonstrated prolonged intestinal retention and superior efficacy compared with unmodified morin and MNs alone. Moreover, MNs notably improved glucose uptake in HepG2 cells. Furthermore, M@SA microgels effectively regulated blood glucose, lipid profiles, and oxidative stress in diabetic mice while mitigating liver, kidney, and pancreatic damage and enhancing anti-inflammatory responses. Our findings propose a promising strategy for the oral administration of natural compounds for blood glucose regulation, with implications for broader therapeutic applications.

6.
Mol Cell Proteomics ; : 100769, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641227

RESUMO

BACKGROUND: The understanding of dynamic plasma proteome features in hybrid immunity and breakthrough infection is limited. A deeper understanding of the immune differences between heterologous and homologous immunization could assist in the future establishment of vaccination strategies. METHODS: In this study, 40 participants who received a third dose of either a homologous BBIBP-CorV or a heterologous ZF2001 protein subunit vaccine following two doses of inactivated coronavirus disease 2019 vaccines and 12 patients with BA.2.2 breakthrough infections were enrolled. Serum samples were collected at Days 0, 28, and 180 following the boosting vaccination and breakthrough and then analyzed using neutralizing antibody tests and mass spectrometer-based proteomics. Mass cytometry of peripheral blood mononuclear cell samples was also performed in this cohort. RESULTS: The chemokine signaling pathway and humoral response markers (IgG2 and IgG3) associated with infection were found to be upregulated in breakthrough infections compared to vaccination-induced immunity. Elevated expression of IGKV, IGHV, IL-17 signaling, and the phagocytosis pathway, along with lower expression of FGL2, were correlated with higher antibody levels in the boosting vaccination groups. The MAPK signaling pathway and Fc gamma R-mediated phagocytosis were more enriched in the heterologous immunization groups than in the homologous immunization groups. CONCLUSION: Breakthrough infections can trigger more intensive inflammatory chemokine responses than vaccination. T-cell and innate immune activation have been shown to be closely related to enhanced antibody levels after vaccination and therefore might be potential targets for vaccine adjuvant design.

7.
ACS Omega ; 9(15): 17344-17353, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38645362

RESUMO

To assess the impact of sulfate mine water on filling material performance, an accelerated sulfate erosion process was used to analyze the effects of various erosion concentrations, aging periods, and cation types on the macroscopic properties of the filling paste. These properties encompassed apparent phenomena, mass changes, and alterations in the uniaxial compressive strength. Observations revealed sulfate erosion, causing the formation of white substances and salt crystals on specimen surfaces. Initially, all solution-eroded specimens exhibited increased mass and strength. Over time, specimens in 5 and 10% MgSO4 solutions displayed the first signs of decline, while variations in other solutions were relatively small. Increasing the erosion concentration led to greater variations in mass and strength during the initial erosion phase. Specimens in 5 and 10% MgSO4 solutions initially peaked in mass and compressive strength, followed by a decline, while other filling paste specimens continued slow increases. Under equivalent conditions, the MgSO4 solution exhibited stronger erosion than the Na2SO4 solution. Composite erosion by Na2SO4 and MgSO4 involved initial strengthening and gel pore filling, intermediate expansion and crystallization, and late-stage substantial degradation, with MgSO4 exhibiting a more pronounced and complex impact. Gray relational analysis ranked factors affecting mass and uniaxial compressive strength variations as erosion concentration > erosion ion type > erosion aging period. Correlation degrees for factors influencing mass variations were 0.8822, 0.8714, and 0.4754, while for factors influencing uniaxial compressive strength variations, the correlation degrees were 0.8336, 0.7943, and 0.6125, respectively.

8.
Patterns (N Y) ; 5(4): 100930, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38645770

RESUMO

Asymmetry is an important property of brain organization, but its nature is still poorly understood. Capturing the neuroanatomical components specific to each hemisphere facilitates the understanding of the establishment of brain asymmetry. Since deep generative networks (DGNs) have powerful inference and recovery capabilities, we use one hemisphere to predict the opposite hemisphere by training the DGNs, which automatically fit the built-in dependencies between the left and right hemispheres. After training, the reconstructed images approximate the homologous components in the hemisphere. We use the difference between the actual and reconstructed hemispheres to measure hemisphere-specific components due to asymmetric expression of environmental and genetic factors. The results show that our model is biologically plausible and that our proposed metric of hemispheric specialization is reliable, representing a wide range of individual variation. Together, this work provides promising tools for exploring brain asymmetry and new insights into self-supervised DGNs for representing the brain.

9.
Opt Lett ; 49(8): 1965-1968, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621052

RESUMO

We propose a concise hardware architecture supporting efficient exclusive OR (XOR) and exclusive NOR (XNOR) operations, by employing a single photonic spiking neuron based on a passive add-drop microring resonator (ADMRR). The threshold mechanism and inhibitory dynamics of the ADMRR-based spiking neuron are numerically discussed on the basis of the coupled mode theory. It is shown that a precise XOR operation in the ADMRR-based spiking neuron can be implemented by adjusting temporal differences within the inhibitory window. Additionally, within the same framework, the XNOR function can also be carried out by accumulating the input power over time to trigger an excitatory behavior. This work presents a novel, to the best of our knowledge, and pragmatic technique for optical neuromorphic computing and information processing utilizing passive devices.

10.
Foodborne Pathog Dis ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608217

RESUMO

This study aimed to assess the clinical characteristics, treatment, and prognosis of osteoarticular brucellosis. We conducted a retrospective study enrolling brucellosis patients from the Sixth People's Hospital of Shenyang between September 2014 and June 2019. A total of 1917 participants were admitted during this period. After applying propensity score matching, we retrospectively analyzed 429 patients with osteoarthritis and 429 patients without osteoarthritis. The primary outcome was treatment completion. The secondary outcome was symptom disappearance and seroconversion. Brucellosis patients with osteoarthritis had longer treatment course (160 [134.3-185.7] vs. 120 [102.3-137.7] d, p = 0.008) than those without osteoarthritis. The most common involved site was lumbar vertebrae (290 [67.6%]) in brucellosis patients with osteoarthritis. Longer symptom duration (90 [83.0-97.0] vs. 42 [40.2-43.8], p < 0.001) along with no significant difference in seroconversion (180 [178.8-181.2] vs. 180 [135.1-224.9], p = 0.212) was observed in osteoarthritis patients with treatment course >90 d. Peripheral joint involvement (adjusted hazard ratio [95% confidence interval] 1.485 [1.103-1.999]; p = 0.009) had a shorter symptom duration compared with shaft joint involvement. No significant differences were observed in treatment therapy between doxycycline plus rifampin (DR) or plus cephalosporins (DRC) in treatment course (p = 0.190), symptom persistence (p = 0.294), and seroconversion (p = 0.086). Lumbar vertebra was the most commonly involved site. Even if all symptoms disappeared, Serum agglutination test potentially remained positive in some patients. Compared with peripheral arthritis, shaft arthritis was the high-risk factor for longer symptom duration. The therapeutic effects were similar between DR and DRC. In summary, our study provided important insights into the clinical characteristics, treatment, and outcomes of osteoarticular brucellosis. Clinical Trial Registration number: NCT04020536.

11.
Vet Parasitol ; : 110175, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38614824

RESUMO

As an intracellular parasitic nematode, Trichinella spiralis (T. spiralis) can induce the formation of nurse cells (NC) in host muscles and keep it to survive within the NC for an extended period. The formation of NC is similar to muscle cell injury and repair which lead to the arrest of satellite cells in the G2/M phase and build a suitable parasitic environment for the muscle larvae of T. spiralis. However, the molecular mechanisms involved in skeletal muscle repair through skeletal muscle satellite cells (SMSC) and the host immune response during T. spiralis infection have not been fully elucidated. In this study, histopathological examination revealed that the severity of damage increased as the infection progressed in the soleus muscle. SMSCs were isolated from BALB/c mice infected with T. spiralis at 4, 21 and 35 days post-infection (dpi). The immunological characteristics of these cells were analyzed by real-time PCR and flow cytometry (FCM). FCM analysis revealed a notable increase in the expression of B7 homolog 1 (B7-H1) in SMSCs following T. spiralis infection, while conversely, the expression of inducible costimulatory ligand (ICOSL) significantly decreased. Furthermore, real-time PCR results showed that toll like receptor 3 (TLR3) expression in SMSCs of the infected mice was upregulated at 21 dpi. The expression levels of three subtypes (PPARα, PPARß and PPARγ) of peroxisome proliferator-activated receptors (PPARs) also increased in the cells. This study highlights the immunological regulation significance of SMSCs host during T. spiralis infection and suggests that SMSCs actively participant in the local immune response to T. spiralis by regulating the interaction between the parasite and the host.

12.
Nat Commun ; 15(1): 2491, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509076

RESUMO

Subgenome dominance has been reported in diverse allopolyploid species, where genes from one subgenome are preferentially retained and are more highly expressed than those from other subgenome(s). However, the molecular mechanisms responsible for subgenome dominance remain poorly understood. Here, we develop genome-wide map of accessible chromatin regions (ACRs) in cultivated strawberry (2n = 8x = 56, with A, B, C, D subgenomes). Each ACR is identified as an MNase hypersensitive site (MHS). We discover that the dominant subgenome A contains a greater number of total MHSs and MHS per gene than the submissive B/C/D subgenomes. Subgenome A suffers fewer losses of MHS-related DNA sequences and fewer MHS fragmentations caused by insertions of transposable elements. We also discover that genes and MHSs related to stress response have been preferentially retained in subgenome A. We conclude that preservation of genes and their cognate ACRs, especially those related to stress responses, play a major role in the establishment of subgenome dominance in octoploid strawberry.


Assuntos
Fragaria , Genoma de Planta , Genoma de Planta/genética , Fragaria/genética , Cromatina/genética , Poliploidia , Mapeamento Cromossômico
13.
Artigo em Inglês | MEDLINE | ID: mdl-38512735

RESUMO

Brain-computer interfaces (BCIs) are anticipated to improve the efficacy of rehabilitation for people with motor disabilities. However, applying BCI in clinical practice is still a challenge due to the great diversity of patients. In the current study, a novel action observation (AO) based BCI was proposed and tested on stroke patients. Ten non-hemineglect patients and ten hemineglect patients were recruited. Four AO stimuli were designed, each presenting a decomposed action to complete the reach-and-grasp task. EEG data and eye movement data were collected. Eye movement data was utilized to analyze the reasons for individual differences in BCI performance. Task discriminative component analysis was utilized to perform online target detection. The results showed that the designed AO-based BCI could simultaneously induce steady state motion visual evoked potential (SSMVEP) from the occipital region and sensory motor rhythm from the sensorimotor region in stroke patients. The average online detection accuracy among the four AO stimuli reached 67% within 3 s in the non-hemineglect group, while the accuracy only reached 35% in the hemineglect group. Gaze metrics showed that the average total duration of fixations during the stimulus phase in the hemineglect group was only 1.31 s ± 0.532 s which was significantly lower than that in the non-hemineglect group. The results indicated that hemineglect patients have difficulty gazing at the AO stimulus, resulting in poor detection performance and weak desynchronization in the sensorimotor region. Furthermore, the degree of neglect is inversely proportional to the target detection accuracy in hemineglect stroke patients. In addition, the gaze metrics associated with cognitive load were significantly correlated with the accuracy in non-hemineglect patients. It indicated the cognitive load may affect the AO-based BCI. The current study will expedite the clinical application of AO-based BCI.


Assuntos
Interfaces Cérebro-Computador , Acidente Vascular Cerebral , Humanos , Potenciais Evocados Visuais , Movimentos Oculares , Eletroencefalografia/métodos
14.
J Fungi (Basel) ; 10(3)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38535185

RESUMO

Isoflavones are predominantly found in legumes and play roles in plant defense and prevention of estrogen-related diseases. Genistein is an important isoflavone backbone with various biological activities. In this paper, we describe how a cell factory that can de novo synthesize genistein was constructed in Saccharomyces cerevisiae. Different combinations of isoflavone synthase, cytochrome P450 reductase, and 2-hydroxyisoflavone dehydratase were tested, followed by pathway multicopy integration, to stably de novo synthesize genistein. The catalytic activity of isoflavone synthase was enhanced by heme supply and an increased intracellular NADPH/NADP+ ratio. Redistribution of the malonyl-CoA flow and balance of metabolic fluxes were achieved by adjusting the fatty acid synthesis pathway, yielding 23.33 mg/L genistein. Finally, isoflavone glycosyltransferases were introduced into S. cerevisiae, and the optimized strain produced 15.80 mg/L of genistin or 10.03 mg/L of genistein-8-C-glucoside. This is the first de novo synthesis of genistein-8-C-glucoside in S. cerevisiae, which is advantageous for the green industrial production of isoflavone compounds.

15.
Hum Brain Mapp ; 45(5): e26573, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38544416

RESUMO

Humans can extract high-level spatial features from visual signals, but spatial representations in the brain are complex and remain unclear. The unsupervised capsule neural network (U-CapsNet) is sensitive to the spatial location and relationship of the object, contains a special recurrent mechanism and uses a self-supervised generation strategy to represent images, which is similar to the computational principle in the human brain. Therefore, we hypothesized that U-CapsNet can help us understand how the human brain processes spatial information. First, brain activities were studied using functional magnetic resonance imaging during spatial working memory in which participants had to remember the locations of circles for a short time. Then, U-CapsNet served as a computational model of the brain to perform tasks that are identical to those performed by humans. Finally, the representational models were used to compare the U-CapsNet with the brain. The results showed that some human-defined spatial features naturally emerged in the latent space of U-CapsNet. Moreover, representations in U-CapsNet captured the response structure of two types of brain regions during different activity patterns, as well as important factors associated with human behavior. Together, our study not only provides a computationally feasible framework for modeling how the human brain encodes spatial features but also provides insights into the representational format and goals of the human brain.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Rememoração Mental , Memória de Curto Prazo , Redes Neurais de Computação , Imageamento por Ressonância Magnética
16.
Pharmacol Res ; : 107162, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38554788

RESUMO

In American men, the incidence of prostate cancer (PC) is the highest among all types of cancer, making it the second leading cause of mortality associated with cancer. For advanced or metastatic PC, antiandrogen therapies are standard treatment options. The administration of these treatments unfortunately carries the potential risk of inducing neuroendocrine prostate cancer (NEPC). Neuroendocrine differentiation (NED) serves as a crucial indicator of prostate cancer development, encompassing various factors such as phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR), Yes-associated protein 1 (YAP1), AMP-activated protein kinase (AMPK), miRNA. The processes of autophagy and ferroptosis (an iron-dependent form of programmed cell death) play pivotal roles in the regulation of various types of cancers. Clinical trials and preclinical investigations have been conducted on many signaling pathways during the development of NEPC, with the deepening of research, autophagy and ferroptosis appear to be the potential target for regulating NEPC. Due to the dual nature of autophagy and ferroptosis in cancer, gaining a deeper understanding of the developmental programs associated with achieving autophagy and ferroptosis may enhance risk stratification and treatment efficacy for patients with NEPC.

17.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(3): 373-379, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38500434

RESUMO

Objective: To provide a comprehensive overview of the surgical treatments of osteochondral lesion of talus (OLT) and offer valuable insights for clinical practice. Methods: The advantages and limitations of surgical treatments for OLT were comprehensively summarized through an extensive review of domestic and abroad relevant literature in recent years. Results: Currently, there exist numerous surgical treatments for the OLT, all of which can yield favorable outcomes. However, each method possesses its own set of merits and demerits. The short-term effectiveness of bone marrow stimulation in treating primary OLT with a diameter less than 15 mm is evident, but its long-term effectiveness diminishes over time. Autologous osteochondral transplantation (AOT) and osteochondral allograft transplantation (OAT) are suitable for OLT with large defects and subchondral bone cysts. However, incomplete anatomical matching between the donor and recipient bones may results in the formation of new subchondral bone cysts, while AOT also presents potential complications at the donor site. In contrast to AOT and OAT, particulated juvenile cartilage allograft transplantation obviates the need for additional osteotomy. Furthermore, juvenile cartilage exhibits enhanced potential in delivering active chondrocytes to the site of cartilage defect, surpassing that of adult cartilage in tissue repair efficacy. Cell transplantation has demonstrated satisfactory effectiveness; however, it is associated with challenges such as the requirement for secondary surgery and high costs. Autologous matrix-induced chondrogenesis technology has shown promising effectiveness in the treatment of primary and non-primary OLT and OLT with large defect and subchondral bone cysts. However, there is a scarcity of relevant studies, most of which exhibit low quality. Adjuvant therapy utilizing biological agents represents a novel approach to treating OLT; nevertheless, due to insufficient support from high-quality studies, it has not exhibited significant advantages over traditional treatment methods. Furthermore, its long-term effectiveness remain unclear. Conclusion: The optimal choice of surgical treatment for OLT is contingent not only upon the characteristics such as nature, size, and shape but also takes into consideration factors like advancements in medical technology, patient acceptance, economic status, and other pertinent aspects to deliver personalized treatment.


Assuntos
Cistos Ósseos , Cartilagem Articular , Fraturas Intra-Articulares , Tálus , Adulto , Humanos , Tálus/cirurgia , Cartilagem/transplante , Condrócitos , Transplante Autólogo , Transplante Ósseo/métodos , Resultado do Tratamento , Cartilagem Articular/cirurgia , Estudos Retrospectivos , Imageamento por Ressonância Magnética
18.
J Agric Food Chem ; 72(14): 7933-7942, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38546719

RESUMO

Ethanol (EtOH) has been identified as a potential pathogenic factor in gastric ulcer development primarily due to its association with gastric injury and excessive production of reactive oxygen species. Magnolol (Mag), the principal active compound in Magnolia officinalis extract, is well studied for its notable anti-inflammatory and antioxidant properties. However, its limited solubility, propensity for agglomeration, and low absorption and utilization rates significantly restrict its therapeutic use. This study aims to overcome these challenges by developing a Mag nanoparticle system targeting the treatment and prevention of EtOH-induced gastric ulcers in mice. Utilizing a click chemistry approach, we successfully synthesized this system by reacting thiolated bovine serum albumin (BSA·SH) with Mag. The in vitro analysis revealed effective uptake of the BSA·SH-Mag nanoparticle system by human gastric epithelial cells (GES-1), showcasing its antioxidant and anti-inflammatory capabilities. Additionally, BSA·SH-Mag exhibited gradual disintegration and release in simulated gastric fluid, resulting in a notable reduction of oxidative stress in gastric tissues and mucosal tissue repair and effectively reducing inflammatory expression. Furthermore, BSA·SH-Mag attenuated EtOH-induced gastric inflammation by decreasing the level of NOX4 protein expression and augmenting the level of Nrf2 protein expression. In conclusion, our findings indicate that BSA·SH-Mag represents a promising candidate as an oral therapeutic for gastric ulcer treatment.


Assuntos
Compostos de Bifenilo , Lignanas , Nanopartículas , Úlcera Gástrica , Camundongos , Humanos , Animais , Etanol/efeitos adversos , Etanol/metabolismo , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Antioxidantes/metabolismo , Anti-Inflamatórios/farmacologia , Mucosa Gástrica/metabolismo
19.
mBio ; 15(4): e0351023, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38470053

RESUMO

Remodeling the erythrocyte membrane and skeleton by the malarial parasite Plasmodium falciparum is closely associated with intraerythrocytic development. However, the mechanisms underlying this association remain unclear. In this study, we present evidence that erythrocytic α-spectrin, but not ß-spectrin, was dynamically ubiquitinated and progressively degraded during the intraerythrocytic development of P. falciparum, from the ring to the schizont stage. We further observed an upregulated expression of P. falciparum phosphatidylinositol 3-kinase (PfPI3K) in the infected red blood cells during the intraerythrocytic development of the parasite. The data indicated that PfPI3K phosphorylated and activated erythrocytic ubiquitin-protein ligase, leading to increased α-spectrin ubiquitination and degradation during P. falciparum development. We further revealed that inhibition of the activity of PfPI3K impaired P. falciparum development in vitro and Plasmodium berghei infectivity in mice. These findings collectively unveil an important mechanism of PfPI3K-ubiquitin-mediated degradation of α-spectrin during the intraerythrocytic development of Plasmodium species. Proteins in the PfPI3K regulatory pathway are novel targets for effective treatment of severe malaria. IMPORTANCE: Plasmodium falciparum is the causative agent of severe malaria that causes millions of deaths globally. The parasite invades human red blood cells and induces a cascade of alterations in erythrocytes for development and proliferation. Remodeling the host erythrocytic cytoskeleton is a necessary process during parasitization, but its regulatory mechanisms remain to be elucidated. In this study, we observed that erythrocytic α-spectrin is selectively degraded after P. falciparum invasion, while ß-spectrin remained intact. We found that the α-spectrin chain was profoundly ubiquitinated by E3 ubiquitin ligase and degraded by the 26S proteasome. E3 ubiquitin ligase activity was regulated by P. falciparum phosphatidylinositol 3-kinase (PfPI3K) signaling. Additionally, blocking the PfPI3K-ubiquitin-proteasome pathway in P. falciparum-infected red blood cells reduced parasite proliferation and infectivity. This study deepens our understanding of the regulatory mechanisms of host and malarial parasite interactions and paves the way for the exploration of novel antimalarial drugs.


Assuntos
Malária Falciparum , Plasmodium falciparum , Humanos , Animais , Camundongos , Plasmodium falciparum/metabolismo , Espectrina/metabolismo , Espectrina/farmacologia , Eritrócitos/parasitologia , Malária Falciparum/parasitologia , Ubiquitina/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
20.
Biomedicines ; 12(3)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38540274

RESUMO

The emergence of castration-resistant prostate cancer (CRPC) following androgen deprivation therapy (ADT) is associated with increased malignancy and limited treatment options. This study aims to investigate potential connections between immune cell infiltration and inflammatory cytokines with the YAP1/AR/PSA axis by exploring their interactions with autophagy. Our research reveals heightened levels of Yes-associated protein 1 (YAP1) expression in CRPC tissues compared with tissues from androgen-dependent prostate cancer (ADPC) and benign prostate hyperplasia (BPH). Additionally, a correlation was observed between YAP1 and PSA expressions in CRPC tissues, suggesting that YAP1 may exert a regulatory influence on PSA expression within CRPC. Enhanced YAP1 expression in C4-2 cells resulted in the upregulation of androgen receptor (AR) nuclear translocation and intracellular prostate-specific antigen (PSA) levels. Conversely, the suppression of YAP1 led to a decrease in PSA expression, suggesting that YAP1 may positively regulate the PSA in castration-resistant prostate cancer (CRPC) by facilitating AR nuclear import. The modulation of the autophagy activity exerts a significant impact on the expression levels of YAP1, the AR, and the PSA. Moreover, recent advancements in immunity and inflammation studies present promising avenues for potential therapies targeting prostate cancer (PC).

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