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1.
Front Bioeng Biotechnol ; 12: 1382085, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38572358

RESUMEN

In this study, a high-efficiency superparamagnetic drug delivery system was developed for preclinical treatment of bladder cancer in small animals. Two types of nanoparticles with magnetic particle imaging (MPI) capability, i.e., single- and multi-core superparamagnetic iron oxide nanoparticles (SPIONs), were selected and coupled with bladder anti-tumor drugs by a covalent coupling scheme. Owing to the minimal particle size, magnetic field strengths of 270 mT with a gradient of 3.2 T/m and 260 mT with a gradient of 3.7 T/m were found to be necessary to reach an average velocity of 2 mm/s for single- and multi-core SPIONs, respectively. To achieve this, a method of constructing an in vitro magnetic field for drug delivery was developed based on hollow multi-coils arranged coaxially in close rows, and magnetic field simulation was used to study the laws of the influence of the coil structure and parameters on the magnetic field. Using this method, a magnetic drug delivery system of single-core SPIONs was developed for rabbit bladder therapy. The delivery system consisted of three coaxially and equidistantly arranged coils with an inner diameter of Φ50 mm, radial height of 85 mm, and width of 15 mm that were positioned in close proximity to each other. CCK8 experimental results showed that the three types of drug-coupled SPION killed tumor cells effectively. By adjusting the axial and radial positions of the rabbit bladder within the inner hole of the delivery coil structure, the magnetic drugs injected could undergo two-dimensional delivery motions and were delivered and aggregated to the specified target location within 12 s, with an aggregation range of about 5 mm × 5 mm. In addition, the SPION distribution before and after delivery was imaged using a home-made open-bore MPI system that could realistically reflect the physical state. This study contributes to the development of local, rapid, and precise drug delivery and the visualization of this process during cancer therapy, and further research on MPI/delivery synchronization technology is planned for the future.

2.
Exp Brain Res ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563979

RESUMEN

Cerebral small vessel disease (CSVD) is increasingly being recognized as a leading contributor to cognitive impairment in the elderly. However, there is a lack of effective preventative or therapeutic options for CSVD. In this exploratory study, we investigated the interplay between neuroinflammation and CSVD pathogenesis as well as the cognitive performance, focusing on NLRP3 signaling as a new therapeutic target. Spontaneously hypertensive stroke-prone (SHRSP) rats served as a CSVD model. We found that SHRSP rats showed decline in learning and memory abilities using morris water maze test. Activated NLRP3 signaling and an increased expression of the downstream pro-inflammatory factors, including IL (interleukin)-6 and tumor necrosis factor α were determined. We also observed a remarkable increase in the production of pyroptosis executive protein gasdermin D, and elevated astrocytic and microglial activation. In addition, we identify several neuropathological hallmarks of CSVD, including blood-brain barrier breakdown, white matter damage, and endothelial dysfunction. These results were in correlation with the activation of NLRP3 inflammasome. Thus, our findings reveal that the NLRP3-mediated inflammatory pathway could play a central role in the pathogenesis of CSVD, presenting a novel target for potential CSVD treatment.

3.
Ying Yong Sheng Tai Xue Bao ; 35(3): 669-677, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38646754

RESUMEN

As one of the important blue carbon pools in tropical and subtropical intertidal zones, mangroves are widely distributed along the coast of Guangxi in China. To deeply explore the variations of potential suitable habitats for mangroves in China under the background of climate change, based on remote sensing interpretation data of coastal wetlands in Guangxi, global marine environment and bioclimatic environment data in 2021, we constructed a maximum entropy habitat distribution model to simulate the spatial distribution of potential suitable areas for mangroves and the invasive species, Spartina alterniflora, along the coast of Guangxi, and predicted the patterns under extreme climate change scenarios (SSP5-8.5). The results showed that the interpreted area of mangrove forests along the coastline of Guangxi was 9136.7 hm2 in 2021, while the predicted area of potential suitable habitat area was 55955.9 hm2. Current distribution area of mangroves had basically covered its potential high suitability area and nearly 10% of the moderate suitability area. The current area of S. alterniflora was 1320.4 hm2, and the predicted area of potential high suitability area was twice of current area, indicating that there was still a large proportion of high suitability area that was not occupied by S. alterniflora. The most important environmental factors driving the distribution of potential habitats in mangroves were offshore Euclidean distance (62.2%), terrain deviation index (8.7%), average sea surface temperature in the hottest season (6.1%), and seabed terrain elevation (5.6%). The contribution of geographical conditions on mangrove distribution was predominant. Under the climate change scenario (SSP5-8.5), potential suitable area for mangroves would increase by 5.3%, while that for S. alterniflora would decrease by 3.1%. The overlapping proportion of the potential suitable area for mangroves and S. alterniflora was similar under current and SSP5-8.5 scenarios, being 15.2% and 14.5%, respectively. In the future, it is necessary to strengthen the protection and ecological restoration of mangroves along the coast of Guangxi and there is great challenge for preventing further invasion of S. alterniflora.


Asunto(s)
Cambio Climático , Ecosistema , Especies Introducidas , Poaceae , Rhizophoraceae , Humedales , China , Rhizophoraceae/crecimiento & desarrollo , Poaceae/crecimiento & desarrollo , Océanos y Mares , Predicción , Modelos Teóricos , Conservación de los Recursos Naturales
4.
Soft Matter ; 20(16): 3392-3400, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38619075

RESUMEN

The recent discovery of ferroelectric nematics provides new opportunities for exploring polar topology in liquid matter. Here, we report numerous potential polarization topological states (e.g., polar vortex-like and line disclination mediated structures) in confined ferroelectric nematics with similar free-energy levels. In the experiment, they appear according to the confinement size and surface anchoring conditions. Based on a minimal analytical approach, we reveal that the topological transformation is balanced among the nematic elasticity, the polarization gradient, the flexoelectric and the depolarization interactions.

5.
Phys Chem Chem Phys ; 26(16): 12422-12432, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38619386

RESUMEN

In traditional chiral nematic liquid crystals, the apolar cholesterics, the dielectric effect is the main driving force for responding to an electric field. The emerging polar chiral nematics, dubbed helielectric nematics, are the polar counterparts of the cholesterics. The head-to-tail symmetry breaking of the new matter state enables it to respond sensitively to the polarity of an electric field. Here, we report on the observation of a sequential polar winding/unwinding process of polarization helices under an electric field applied perpendicular to the helical axes, which behaves distinctly from the unwinding of the apolar cholesteric helices. Understanding the helix-unwinding behaviors provides insights for developing switchable devices based on helielectric nematics.

6.
World J Surg Oncol ; 22(1): 94, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38610000

RESUMEN

BACKGROUND: Temporary ileostomy (TI) has proven effective in reducing the severity of anastomotic leakage after rectal cancer surgery; however, some ileostomies fail to reverse over time, leading to conversion into a permanent stoma (PS). In this study, we aimed to investigate the preoperative risk factors and cumulative incidence of TI non-closure after sphincter-preserving surgery for rectal cancer. MATERIALS AND METHODS: We conducted a meta-analysis after searching the Embase, Web of Science, PubMed, and MEDLINE databases from their inception until November 2023. We collected all published studies on the risk factors related to TI non-closure after sphincter-preserving surgery for rectal cancer. RESULTS: A total of 1610 studies were retrieved, and 13 studies were included for meta-analysis, comprising 3026 patients. The results of the meta-analysis showed that the identified risk factors included older age (p = 0.03), especially > 65 years of age (p = 0.03), male sex (p = 0.009), American Society of Anesthesiologists score ≥ 3 (p = 0.004), comorbidity (p = 0.001), and distant metastasis (p < 0.001). Body mass index, preoperative hemoglobin, preoperative albumin, preoperative carcinoma embryonic antigen, tumor location, neoadjuvant chemoradiotherapy, smoking, history of abdominal surgery, and open surgery did not significantly change the risk of TI non-closure. CONCLUSION: We identified five preoperative risk factors for TI non-closure after sphincter-preserving surgery for rectal cancer. This information enables surgeons to identify high-risk groups before surgery, inform patients about the possibility of PS in advance, and consider performing protective colostomy or Hartmann surgery.


Asunto(s)
Neoplasias del Recto , Estomas Quirúrgicos , Humanos , Masculino , Ileostomía/efectos adversos , Incidencia , Factores de Riesgo , Neoplasias del Recto/cirugía
7.
Biophys Chem ; 310: 107230, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38615537

RESUMEN

The aggregation of transactive response deoxyribonucleic acid (DNA) binding protein of 43 kDa (TDP-43) into ubiquitin-positive inclusions is closely associated with amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration, and chronic traumatic encephalopathy. The 370-375 fragment of TDP-43 (370GNNSYS375, TDP-43370-375), the amyloidogenic hexapeptides, can be prone to forming pathogenic amyloid fibrils with the characteristic of steric zippers. Previous experiments reported the ALS-associated mutation, serine 375 substituted by glycine (S375G) is linked to early onset disease and protein aggregation of TDP-43. Based on this, it is necessary to explore the underlying molecular mechanisms. By utilizing all-atom molecular dynamics (MD) simulations of 102 µs in total, we investigated the impact of S375G mutation on the conformational ensembles and oligomerization dynamics of TDP-43370-375 peptides. Our replica exchange MD simulations show that S375G mutation could promote the unstructured conformation formation and induce peptides to form a loose packed oligomer, thus inhibiting the aggregation of TDP-43370-375. Further analyses suggest that S375G mutation displays a reduction effect on the number of total hydrogen bonds and contacts among TDP-43370-375 peptides. Hydrogen bonding and polar interactions among TDP-43370-375 peptides, as well as Y374-Y374 π-π stacking interaction, are attenuated by S375G mutation. Additional microsecond MD simulations demonstrate that S375G mutation could prohibit the conformational conversion to ß-structure-rich aggregates and possess an inhibitory effect on the oligomerization dynamics of TDP-43370-375. This study offers for the first time of molecular insights into the S375G mutation affecting the aggregation of TDP-43370-375 at the atomic level, and may open new avenues in the development of future site-specific mutation therapeutics.

8.
BMC Musculoskelet Disord ; 25(1): 268, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582828

RESUMEN

BACKGROUND: Knee osteoarthritis (KOA) is a prevalent and debilitating condition that markedly affects the sit-to-stand (STS) activity of patients, a prerequisite for daily activities. Biomechanical recognition of movements in patients with mild KOA is currently attracting attention. However, limited studies have been conducted solely on the observed differences in sagittal plane movement and muscle activation. AIM: This study aimed to identify three-dimensional biomechanical and muscle activation characteristics of the STS activity in patients with mild KOA. METHODS: A cross-sectional study was conducted to observe the differences between patients with mild KOA and a control group (CG). It was conducted to observe the differences in muscle activation, including root mean square (RMS%) and integrated electromyography (items), kinematic parameters like range of motion (ROM) and maximum angular velocity, as well as dynamic parameters such as joint moment and vertical ground reaction force (vGRF). RESULTS: Patients with mild KOA had a higher body mass index and longer task duration. In the sagittal plane, patients with KOA showed an increased ROM of the pelvic region, reduced ROM of the hip-knee-ankle joint, and diminished maximum angular velocity of the knee-ankle joint. Furthermore, patients with KOA displayed increased knee-ankle joint ROM in the coronal plane and decreased ankle joint ROM in the horizontal plane. Integrated vGRF was higher in both lower limbs, whereas the vGRF of the affected side was lower. Furthermore, patients showed a decreased peak adduction moment (PADM) and increased peak external rotation moment in the knee joint and smaller PADM and peak internal rotation moment in the ankle joint. The affected side exhibited decreased RMS% and iEMG values of the gluteus medius, vastus medialis, and vastus lateralis muscles, as well as a decreased RMS% of the rectus femoris muscle. Conversely, RMS% and iEMG values of the biceps femoris, lateral gastrocnemius, and medial gastrocnemius muscles were higher. CONCLUSION: The unbalanced activation characteristics of the anterior and posterior muscle groups, combined with changes in joint moment in the three-dimensional plane of the affected joint, may pose a potential risk of injury to the irritated articular cartilage.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/diagnóstico , Fenómenos Biomecánicos , Estudios Transversales , Extremidad Inferior/fisiología , Músculo Esquelético/fisiología , Articulación de la Rodilla/fisiología , Electromiografía
9.
J Electrocardiol ; 84: 27-31, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38479052

RESUMEN

BACKGROUND: In the field of mobile health, portable dynamic electrocardiogram (ECG) monitoring devices often have a limited number of lead electrodes due to considerations, such as portability and battery life. This situation leads to a contradiction between the demand for standard 12­lead ECG information and the limited number of leads collected by portable devices. METHODS: This study introduces a composite ECG vector reconstruction network architecture based on convolutional neural network (CNN) combined with recurrent neural network by using leads I, II, and V2. This network is designed to reconstruct three­lead ECG signals into 12­lead ECG signals. A 1D CNN abstracts and extracts features from the spatial domain of the ECG signals, and a bidirectional long short-term memory network analyzes the temporal trends in the signals. Then, the ECG signals are inputted into the model in a multilead, single-channel manner. RESULTS: Under inter-patient conditions, the mean reconstructed Root mean squared error (RMSE) for precordial leads V1, V3, V4, V5, and V6 were 28.7, 17.3, 24.2, 36.5, and 25.5 µV, respectively. The mean overall RMSE and reconstructed Correlation coefficient (CC) were 26.44 µV and 0.9562, respectively. CONCLUSION: This paper presents a solution and innovative approach for recovering 12­lead ECG information when only three­lead information is available. After supplementing with comprehensive leads, we can analyze the cardiac health status more comprehensively across 12 dimensions.

10.
Materials (Basel) ; 17(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38473638

RESUMEN

The differences in geomechanical properties and the uncertainty in the spatial distribution of Bimrock pose significant challenges to the construction and disaster prediction of geotechnical engineering. To clarify the geomechanical characteristics of Bimrock, this paper summarizes the basic concepts and classification methods of Bimrock at home and abroad. It discusses the methods and characteristics of determining the geometric features of Bimrock blocks and explores the influencing factors and laws of failure modes and strength under different stress states of Bimrock. The study finds that the failure mode of Bimrock is mainly influenced by factors such as block proportion, degree of welding between blocks and matrix, strength ratio between blocks and matrix, and geometric properties of blocks. Among these factors, block proportion is the most significant, and the degree of welding is a controlling factor. However, due to the complexity of Bimrock structures, there is a lack of applicable methods and mechanical models for the evaluation of geomechanical characteristics of Bimrock in engineering practice. This article also explores the influence and research methods of the geological characteristics of Bimrock in slope and tunnel engineering and, finally, provides prospects for the future research trends relating to Bimrock.

11.
Clin Transl Med ; 14(3): e1605, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38445456

RESUMEN

BACKGROUND: Bone or brain metastases may develop in 20-40% of individuals with late-stage non-small-cell lung cancer (NSCLC), resulting in a median overall survival of only 4-6 months. However, the primary lung cancer tissue's distinctions between bone, brain and intrapulmonary metastases of NSCLC at the single-cell level have not been underexplored. METHODS: We conducted a comprehensive analysis of 14 tissue biopsy samples obtained from treatment-naïve advanced NSCLC patients with bone (n = 4), brain (n = 6) or intrapulmonary (n = 4) metastasis using single-cell sequencing originating from the lungs. Following quality control and the removal of doublets, a total of 80 084 cells were successfully captured. RESULTS: The most significant inter-group differences were observed in the fraction and function of fibroblasts. We identified three distinct cancer-associated fibroblast (CAF) subpopulations: myofibroblastic CAF (myCAF), inflammatory CAF (iCAF) and antigen-presenting CAF (apCAF). Notably, apCAF was prevalent in NSCLC with bone metastasis, while iCAF dominated in NSCLC with brain metastasis. Intercellular signalling network analysis revealed that apCAF may play a role in bone metastasis by activating signalling pathways associated with cancer stemness, such as SPP1-CD44 and SPP1-PTGER4. Conversely, iCAF was found to promote brain metastasis by activating invasion and metastasis-related molecules, such as MET hepatocyte growth factor. Furthermore, the interaction between CAFs and tumour cells influenced T-cell exhaustion and signalling pathways within the tumour microenvironment. CONCLUSIONS: This study unveils the direct interplay between tumour cells and CAFs in NSCLC with bone or brain metastasis and identifies potential therapeutic targets for inhibiting metastasis by disrupting these critical cell-cell interactions.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Encéfalo , Fibroblastos , Microambiente Tumoral
12.
Biochem Biophys Res Commun ; 707: 149513, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38508051

RESUMEN

Cancer is a significant global health concern, and finding effective methods to treat it has been a focus of scientific research. It has been discovered that the growth, invasion, and metastasis of tumors are closely related to the environment in which they exist, known as the tumor microenvironment (TME). The immune response interacting with the tumor occurring within the TME constitutes the tumor immune microenvironment, and the immune response can lead to anti-tumor and pro-tumor outcomes and has shown tremendous potential in immunotherapy. A channel called the P2X7 receptor (P2X7R) has been identified within the TME. It is an ion channel present in various immune cells and tumor cells, and its activation can lead to inflammation, immune responses, angiogenesis, immunogenic cell death, and promotion of tumor development. This article provides an overview of the structure, function, and pharmacological characteristics of P2X7R. We described the concept and components of tumor immune microenvironment and the influence immune components has on tumors. We also outlined the impact of P2X7R regulation and how it affects the development of tumors and summarized the effects of drugs targeting P2X7R on tumor progression, both past and current, assisting researchers in treating tumors using P2X7R as a target.


Asunto(s)
Neoplasias , Receptores Purinérgicos P2X7 , Microambiente Tumoral , Humanos , Neoplasias/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Animales
13.
ACS Nano ; 18(14): 10142-10155, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38526307

RESUMEN

Fully mobilizing the activities of multiple immune cells is crucial to achieve the desired tumor immunotherapeutic efficacy yet still remains challenging. Herein, we report a nanomedicine formulation based on phosphorus dendrimer (termed AK128)/programmed cell death protein 1 antibody (aPD1) nanocomplexes (NCs) that are camouflaged with M1-type macrophage cell membranes (M1m) for enhanced immunotherapy of orthotopic glioma. The constructed AK128-aPD1@M1m NCs with a mean particle size of 160.3 nm possess good stability and cytocompatibility. By virtue of the decorated M1m having α4 and ß1 integrins, the NCs are able to penetrate the blood-brain barrier to codeliver both AK128 with intrinsic immunomodulatory activity and aPD1 to the orthotopic glioma with prolonged blood circulation time. We show that the phosphorus dendrimer AK128 can boost natural killer (NK) cell proliferation in peripheral blood mononuclear cells, while the delivered aPD1 enables immune checkpoint blockade (ICB) to restore the cytotoxic T cells and NK cells, thus promoting tumor cell apoptosis and simultaneously decreasing the tumor distribution of regulatory T cells vastly for improved glioma immunotherapy. The developed nanomedicine formulation with a simple composition achieves multiple modulations of immune cells by utilizing the immunomodulatory activity of nanocarrier and antibody-mediated ICB therapy, providing an effective strategy for cancer immunotherapy.


Asunto(s)
Dendrímeros , Glioma , Humanos , Fósforo , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Biomimética , Glioma/terapia , Glioma/patología , Inmunoterapia , Células Asesinas Naturales , Anticuerpos/metabolismo , Linfocitos T Citotóxicos , Barrera Hematoencefálica/metabolismo , Microambiente Tumoral
14.
Polymers (Basel) ; 16(6)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38543354

RESUMEN

Thermal damage due to microstructure changes will occur in propellants under thermal stimulation. It can significantly affect the sensitization, combustion, and other properties of the propellant, which, in turn, affects the impact safety of the solid propellant rocket engine. A new component which uniformly heats the sample was designed to conduct the Lagrange test and EFP impact test at different temperatures. The thermal decomposition and damage characteristics of the propellant during the heating process were quantitatively analyzed. Additionally, the effects of ambient temperature on impact initiation and detonation growth of the high-energy propellant were elucidated at a mesoscopic level. The results showed that the porosity of the specimen increased by 0.89% under the thermomechanical mechanism, which was mainly characterized by interfacial de-bonding between the AP and the binder. The increase in thermal damage changed the hot spot reaction rate and significantly affected the growth process of propellant impact initiation. A method was proposed to systematically calibrate the reaction rate model for the propellant at different temperatures. The theoretical model parameters of the high-energy propellant at two typical temperatures were calibrated in this way. The critical shell thicknesses computed using LS-DYNA, which, for 20 and 70 °C, were obtained as 15 and 20 mm, respectively.

15.
Can J Gastroenterol Hepatol ; 2024: 2410643, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38550348

RESUMEN

Background: Protective ileostomy can effectively prevent severe anastomotic leakage after rectal cancer surgery; however, the optimal timing for ileostomy closure during adjuvant chemotherapy remains unclear. This study aimed to explore the safety and long-term outcomes of early ileostomy closure during adjuvant chemotherapy. Method: Patients who underwent laparoscopic rectal cancer surgery combined with protective ileostomy and adjuvant chemotherapy between April 2017 and April 2021 were retrospectively evaluated. Patients were divided into an early closure group during chemotherapy (group A) and a late closure group after chemotherapy (group B). Results: A total of 215 patients were included in this study, with 115 in group A and 100 in group B. There were no significant differences in demographic and clinical characteristics between the two groups. In group A, durations of stoma status (p < 0.001) and low anterior resection syndrome (LARS) (p < 0.001) were shorter, and rectal stenosis (p=0.036) and stoma-related complications (p=0.007), especially stoma stenosis (p=0.041), were less common. However, compliance with chemotherapy was worse (p=0.009). There were no significant differences in operative time, postoperative hospital stay, postoperative complications, incidence and severity of LARS, disease-free survival, or overall survival between groups. Conclusion: Early ileostomy closure can effectively reduce the duration of stoma status, duration of LARS, rectal stenosis, and stoma-related complications while not affecting surgical complications and oncological outcomes. Ileostomy closure should not be delayed because of adjuvant chemotherapy. However, follow-up should be strengthened to increase compliance and integrity with chemotherapy.


Asunto(s)
Ileostomía , Neoplasias del Recto , Humanos , Ileostomía/efectos adversos , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/cirugía , Neoplasias del Recto/complicaciones , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Constricción Patológica/complicaciones , Síndrome , Quimioterapia Adyuvante
16.
J Chem Inf Model ; 64(8): 3386-3399, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38489841

RESUMEN

Aggregation of tau protein into intracellular fibrillary inclusions is characterized as the hallmark of tauopathies, including Alzheimer's disease and chronic traumatic encephalopathy. The microtubule-binding (MTB) domain of tau, containing either three or four repeats with sequence similarities, plays an important role in determining tau's aggregation. Previous studies have reported that abnormal acetylation of lysine residues displays a distinct effect on the formation of pathological tau aggregates. However, the underlying molecular mechanism remains mostly elusive. In this study, we performed extensive replica exchange molecular dynamics (REMD) simulations of 144 µs in total to systematically investigate the dimerization of four tau MTB repeats and explore the impacts of Lys280 (K280) or Lys321 (K321) acetylation on the conformational ensembles of the R2 or R3 dimer. Our results show that R3 is the most prone to aggregation among the four repeats, followed by R2 and R4, while R1 displays the weakest aggregation propensity with a disordered structure. Acetylation of K280 could promote the aggregation of R2 peptides by increasing the formation of ß-sheet structures and strengthening the interchain interaction. However, K321 acetylation decreases the ß-sheet content of the R3 dimer, reduces the ability of R3 peptides to form long ß-strands, and promotes the stable helix structure formation. The salt bridge and Y310-Y310 π-π stacking interactions of the R3 dimer are greatly weakened by K321 acetylation, resulting in the inhibition of dimerization. This study uncovers the structural ensembles of tau MTB repeats and provides mechanistic insights into the influences of acetylation on tau aggregation, which may deepen the understanding of the pathogenesis of tauopathies.


Asunto(s)
Microtúbulos , Simulación de Dinámica Molecular , Agregado de Proteínas , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/química , Acetilación , Microtúbulos/metabolismo , Multimerización de Proteína , Unión Proteica , Humanos , Conformación Proteica
17.
Front Microbiol ; 15: 1353710, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38511011

RESUMEN

Introduction: Cordyceps cicadae is a traditional Chinese medicinal fungus known for its rich production of bioactive substances, particularly cyanidin, an anthocyanin commonly found in plants with notable anti-inflammatory, anti-tumor, antiviral, and antibacterial properties. This study revealed two key genes, CcDFR and CcOMT9, affecting cyanidin biosynthesis in C. cicadae. Methods: The roles of these genes in cyanidin production, growth, and development were elucidated through the gene knockout method, phenotypic analysis, transcriptomics, and metabolomics. Results: CcDFR deletion led to reduced cyanidin-3-O-glucoside (C3G), suppressed expression of cyanidin biosynthesis genes, impaired synnemata formation, decreased polysaccharide and adenosine content, and diminished chitinase activity. Meanwhile, the ΔCcOMT9 mutant exhibited an increase in C3G production, promoted expression of cyanidin biosynthesis genes and rising bioactive compounds, suppressed RNA methylation, and led to phenylalanine accumulation with no effect on fruiting body formation. Discussion: We revealed a distinct anthocyanin biosynthesis pathway in C. cicadae and identified two genes with opposite functions, laying the foundation for future genetic modification of cyanidin-producing strains using modern biological techniques. This will shorten the production period of this valuable compound, facilitating the industrial-scale production of cyanidin.

18.
Sci Total Environ ; 922: 171325, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38428604

RESUMEN

Despite the well-established recognition of the health hazards posed by PM2.5-bound PAHs, a comprehensive understanding of their source-specific impact has been lacking. In this study, the health risks associated with PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) and source-specific contributions were investigated in the urban region of Taipei during both cold and warm seasons. The levels of PM2.5-bound PAHs and their potential health risks across different age groups of humans were also characterized. Diagnostic ratios and positive matrix factorization analysis were utilized to identify the sources of PM2.5-bound PAHs. Moreover, potential source contribution function (PSCF), concentration-weighted trajectory (CWT) and source regional apportionment (SRA) analyses were employed to determine the potential source regions. Results showed that the total PAHs (TPAHs) concentrations ranged from 0.08 to 2.37 ng m-3, with an average of 0.69 ± 0.53 ng m-3. Vehicular emissions emerged as the primary contributor to PM2.5-bound PAHs, constituting 39.8 % of the TPAHs concentration, followed by industrial emissions (37.6 %), biomass burning (13.8 %), and petroleum/oil volatilization (8.8 %). PSCF and CWT analyses revealed that industrial activities and shipping processes in northeast China, South China Sea, Yellow Sea, and East China Sea, contributed to the occurrence of PM2.5-bound PAHs in Taipei. SRA identified central China as the primary regional contributor of ambient TPAHs in the cold season and Taiwan in the warm season, respectively. Evaluations of incremental lifetime cancer risk demonstrated the highest risk for adults, followed by children, seniors, and adolescents. The assessments of lifetime lung cancer risk showed that vehicular and industrial emissions were the main contributors to cancer risk induced by PM2.5-bound PAHs. This research emphasizes the essential role of precisely identifying the origins of PM2.5-bound PAHs to enhance our comprehension of the related human health hazards, thus providing valuable insights into the mitigation strategies.


Asunto(s)
Contaminantes Atmosféricos , Neoplasias Pulmonares , Hidrocarburos Policíclicos Aromáticos , Niño , Humanos , Adolescente , Contaminantes Atmosféricos/análisis , Estaciones del Año , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Monitoreo del Ambiente/métodos , China , Asia Oriental , Medición de Riesgo
19.
BMJ Open ; 14(3): e081011, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553051

RESUMEN

BACKGROUND: Patients with chronic heart failure (CHF) often have a long duration of illness, difficulty in attending follow-up visits, and poor adherence to treatment. As a result, they frequently cannot receive guideline-directed medical therapy (GDMT) at the desired or maximum tolerable drug dosage. This leads to high hospitalisation and mortality rates for HF patients. Therefore, effective management and monitoring of patients with HF to ensure they receive GDMT is crucial for improving the prognosis. DESIGN AND METHODS: This is a multicentre, open-label, randomised, parallel-group study involving patients with CHF across five centres. The study aims to assess the impact of an optimised GDMT model for HF patients, established on a mobile health (mHealth) platform, compared with a control group. Patients must have a left ventricular ejection fraction of less than 50% and be receiving medication titration therapy that has not yet reached the target dose, with a modest increase in N-terminal pro-B-type natriuretic peptide level. The primary composite outcome is worsening HF events (hospitalisation or emergency treatment with intravenous fluids) or cardiovascular death. ETHICS AND DISSEMINATION: On 22 December 2021, this study received ethical approval from the Ethics Review Board of the First Affiliated Hospital of Nanjing Medical University, with the ethics number 2021-SR-530. All study participants will be informed of the research purpose and their participation will be voluntary. Informed consent will be obtained by providing and signing an informed consent form. We will ensure compliance with relevant laws and regulations regarding privacy and data protection. The results of this study will be published in a peer-reviewed academic journal. We will ensure that the dissemination of study results is accurate, clear and timely. TRIAL REGISTRATION NUMBER: ChiCTR2200056527.


Asunto(s)
Insuficiencia Cardíaca , Telemedicina , Humanos , Volumen Sistólico , Función Ventricular Izquierda , Enfermedad Crónica , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
20.
Eur J Med Chem ; 268: 116252, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38422703

RESUMEN

The modification based on natural products is a practical way to find anti-inflammatory drugs. In this study, 26 osthole derivatives were synthesized, and their anti-inflammatory properties were evaluated. The preliminary activity study revealed that most osthole derivatives could effectively inhibit inflammatory cytokines IL-6 secretion in LPS stimulated mouse macrophages J774A.1. Compound 7m exhibited the most effective anti-inflammatory activity (RAW264.7 IL-6 IC50: 4.57 µM, 32 times more active than osthole) in vitro with no significant influence on cell proliferation. Additionally, the mechanistic analysis demonstrated that compound 7m could block MAPK signal transduction by inhibiting the phosphorylation of JNK and p38, thereby inhibiting the release of inflammatory cytokines. Moreover, in vivo functional investigations revealed that 7m could substantially reduce DSS-induced ulcerative colitis and LPS-induced acute lung injury, with good therapeutic effects. The pharmacokinetics and acute toxicity experiments proved the safety and reliability of 7min vivo. Overall, Compound 7m could further be studied as potential anti-inflammatory candidate.


Asunto(s)
Lesión Pulmonar Aguda , Colitis Ulcerosa , Colitis , Cumarinas , Animales , Ratones , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Lipopolisacáridos/farmacología , Interleucina-6 , Reproducibilidad de los Resultados , Antiinflamatorios/efectos adversos , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Citocinas , FN-kappa B , Ratones Endogámicos C57BL , Colitis/tratamiento farmacológico
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