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1.
J Environ Sci (China) ; 148: 476-488, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095182

RESUMEN

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42-) occupying the active sites on the surface and the inner pores of the adsorbents.


Asunto(s)
Cobre , Sulfuro de Hidrógeno , Oxidación-Reducción , Titanio , Titanio/química , Adsorción , Cobre/química , Sulfuro de Hidrógeno/química , Contaminantes Atmosféricos/química , Gases em Plasma/química , Modelos Químicos
2.
Expert Opin Drug Metab Toxicol ; : 1-16, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225462

RESUMEN

INTRODUCTION: Hepatocellular carcinoma (HCC) accounts for 85% of liver cancer cases and is the third leading cause of cancer death. Regorafenib is a multi-target inhibitor that dramatically prolongs progression-free survival in HCC patients who have failed sorafenib therapy. However, one of the primary factors limiting regorafenib's clinical utilization is toxicity. Using Clinical Trials.gov and PubMed, we gathered clinical data on regorafenib and conducted a extensive analysis of the medication's adverse reactions and mechanisms. Next, we suggested suitable management techniques to improve regorafenib's effectiveness. AREAS COVERED: We have reviewed the mechanisms by which regorafenib-induced toxicity occurs and general management strategies through clinical trials of regorafenib. Furthermore, by examining the literature on regorafenib and other tyrosine kinase inhibition, we summarized the mechanics of the onset of regorafenib toxicity and mechanism-based intervention strategies by reviewing the literature related to regorafenib and other tyrosine kinase inhibition. EXPERT OPINION: One of the primary factors restricting regorafenib's clinical utilization and combination therapy is its toxicity reactions. To optimize regorafenib treatment regimens, it is especially important to further understand the specific toxicity mechanisms of regorafenib as a multi-kinase inhibitor.

3.
Clin Lab ; 70(9)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39257106

RESUMEN

BACKGROUND: This study aimed to investigate the effects of hemoglobin A1c (HbA1c), fasting blood glucose (FBG), 2-hours postprandial blood glucose (2hPBG), and fasting insulin (FINS) levels on pregnancy outcomes and their predictive value in patients with gestational diabetes mellitus (GDM). METHODS: A total of 109 pregnant women with GDM (GDM group) were included and assayed for serum FBG, 2hPBG, HbA1c, and FINS levels. The incidence of adverse pregnancy outcomes was recorded. GDM patients were divided into the poor pregnancy outcome group and the favorable pregnancy outcome group and analyzed for HbA1c, FBG, 2hPBG, and FINS. The predictive value of serum index combined detection on GDM pregnancy outcome was assessed, and the effect of serum indices on pregnancy outcome was evaluated in GDM patients with logistic regression. RESULTS: In the GDM group, there were 8 cases of premature membranes breaking (7.34%), 6 cases of premature delivery (5.50%), 3 cases of hyperamniotic fluid (2.75%), 2 cases of neonatal asphyxia (1.83%), 5 cases of fetal growth restriction (4.59%), and 3 cases of low-birth-weight infants (2.75%). The total incidence of adverse preg-nancy outcomes was 24.77% (27/109). HbA1c, FBG, 2hPBG, and FINS in the poor pregnancy outcome group were higher than those in the favorable pregnancy outcome group. The AUC value of blood biochemical indicators combined detection in predicting pregnancy outcome in GDM patients was higher than of HbA1c, FBG, 2hPBG, and FINS alone detection. HbA1c ≥ 6.94%, FBG ≥ 7.18 mmol/L, 2hPBG ≥ 9.36 mmol/L, and FINS ≥ 13.07 U/L were the risk factors affecting pregnancy outcomes in GDM patients. CONCLUSIONS: The changes of HbA1c, FBG, 2hPBG, and FINS levels in GDM patients are associated with adverse pregnancy outcomes, and the combined detection of serum indicators has predictive value for pregnancy outcomes in GDM patients.


Asunto(s)
Glucemia , Diabetes Gestacional , Hemoglobina Glucada , Valor Predictivo de las Pruebas , Resultado del Embarazo , Humanos , Embarazo , Femenino , Diabetes Gestacional/sangre , Diabetes Gestacional/diagnóstico , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Resultado del Embarazo/epidemiología , Adulto , Glucemia/análisis , Glucemia/metabolismo , Insulina/sangre , Ayuno/sangre
4.
iScience ; 27(8): 110505, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39238652

RESUMEN

Polyadenosine diphosphate-ribose polymerase inhibitors (PARPi) represent a promising novel treatment for castration-resistant prostate cancer (CRPC) with encouraging results. However, the combination targets in CRPC remain largely unexplored. N6-methyladenosine (m6A) has been shown to play a crucial role in cancer progression and DNA damage response. Here, we observed a higher overall level of m6A and a downregulation of Fat mass and obesity-associated protein (FTO), which correlated with unfavorable clinicopathological parameters in prostate cancer (PCa). Functionally, reduced FTO promotes PCa growth, while overexpression of FTO has the opposite effect. Mechanistically, FOXO3a was identified as the downstream target of FTO in PCa. FTO downregulates the expression of FOXO3a in an m6A-dependent manner, leading to the degradation of its mRNA. Importantly, DNA damage can degrade FTO through the ubiquitination pathway. Finally, we found that overexpression of FTO can enhance the effect of PARPi on PCa. Therefore, our findings may provide insight into novel therapeutic approaches for CRPC.

5.
Front Endocrinol (Lausanne) ; 15: 1436217, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39247919

RESUMEN

Objective: Evaluate the effects of sodium-glucose cotransporter 2 inhibitor (SGLT2i) on cardiovascular and cerebrovascular diseases. Methods: Articles of SGLT2i on cardiovascular and cerebrovascular diseases were searched. Two authors independently screened the literature, extracted the data, assessed the quality of the study and performed statistical analyses using Review Manager 5.4. Results: Random-effect model was used to merge the OR values, and the pooled effect showed that SGLT2i had significant preventive effects on cardiovascular death (OR=0.76, 95%CI 0.64 to 0.89), myocardial infarction (OR=0.90, 95%CI 0.84 to 0.96), heart failure (OR=0.69, 95%CI 0.64 to 0.74) and all-cause mortality (OR=0.65, 95%CI 0.58 to 0.73). Empagliflozin, dapagliflozin and canagliflozin all reduced the incidence of heart failure (OR=0.72, 95%CI 0.64 to 0.82; OR=0.56, 95%CI 0.39 to 0.80; OR=0.62, 95%CI 0.53 to 0.73), but only dapagliflozin displayed a favorable effect on inhibiting stroke (OR=0.78, 95%CI 0.63 to 0.98). SGLT2i could prevent stroke (OR=0.86, 95%CI 0.75 to 0.99), heart failure (OR=0.63, 95%CI 0.56 to 0.70) and all-cause mortality (OR=0.64, 95%CI 0.57 to 0.72) compared to DPP-4i. Furthermore, SGLT2i could reduce the incidence of heart failure (OR=0.72, 95%CI 0.67 to 0.77) and cardiovascular death (OR=0.72, 95%CI 0.54 to 0.95) in patients with high-risk factors. Conclusions: SGLT2i affects cardiovascular death, myocardial infarction, heart failure and all-cause mortality. Only dapagliflozin displayed a favorable effect on inhibiting stroke. SGLT2i could prevent stroke, heart failure and all-cause mortality compared to DPP-4i. In addition, SGLT2i significantly reduced the development of heart failure and cardiovascular death in patients with high-risk factors. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier CRD42024532783.


Asunto(s)
Enfermedades Cardiovasculares , Trastornos Cerebrovasculares , Diabetes Mellitus Tipo 2 , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/tratamiento farmacológico , Trastornos Cerebrovasculares/prevención & control , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Compuestos de Bencidrilo/uso terapéutico , Glucósidos/uso terapéutico , Ensayos Clínicos Controlados como Asunto , Hipoglucemiantes/uso terapéutico
6.
FEBS J ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250546

RESUMEN

Cyclin-dependent kinase 9 (CDK9), a catalytic subunit of the positive transcription elongation factor b (P-TEFb) complex, is a global transcriptional elongation factor associated with cell proliferation. CDK9 activity is regulated by certain histone acetyltransferases, such as p300, GCN5 and P/CAF. However, the impact of males absent on the first (MOF) (also known as KAT8 or MYST1) on CDK9 activity has not been reported. Therefore, the present study aimed to elucidate the regulatory role of MOF on CDK9. We present evidence from systematic biochemical assays and molecular biology approaches arguing that MOF interacts with and acetylates CDK9 at the lysine 35 (i.e. K35) site, and that this acetyl-group can be removed by histone deacetylase HDAC1. Notably, MOF-mediated acetylation of CDK9 at K35 promotes the formation of the P-TEFb complex through stabilizing CDK9 protein and enhancing its association with cyclin T1, which further increases RNA polymerase II serine 2 residues levels and global transcription. Our study reveals for the first time that MOF promotes global transcription by acetylating CDK9, providing a new strategy for exploring the comprehensive mechanism of the MOF-CDK9 axis in cellular processes.

7.
Gen Hosp Psychiatry ; 91: 1-10, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39243483

RESUMEN

BACKGROUND: Late-life depression, often accompanied by cognitive impairment, poses significant clinical challenges owing to its complex etiology and diverse manifestations. While antidepressants like venlafaxine and anxiolytics such as buspirone are effective for treating depression, their effects on cognitive function remain less well-understood. With the aging population increasingly experiencing geriatric depression, there is an urgent need for innovative treatment approaches that address both depressive symptoms and cognitive impairments. OBJECTIVE: This study aimed to evaluate the clinical efficacy and safety of combined buspirone and venlafaxine therapy in elderly patients diagnosed with geriatric depression accompanied by cognitive impairment. METHODS: A 12-week, randomized controlled trial was conducted involving 170 elderly patients. Participants were randomized into two groups: one receiving venlafaxine alone (control group) and the other receiving a combination of venlafaxine and buspirone (experimental group). The primary analysis was performed using an Intent-to-Treat (ITT) approach with mixed-effects linear models to assess changes in depressive symptoms, cognitive function, and anxiety levels. A supplementary Per-Protocol (PP) analysis, utilizing repeated measures ANOVA, was also conducted. RESULTS: The ITT analysis showed that the combination therapy significantly reduced depressive symptoms, as indicated by the HAMD-17 scores (p = 0.033 at week 12). Cognitive function, as measured by MoCA scores, also improved significantly in the experimental group by week 12 (p = 0.025). However, no statistically significant differences were observed in anxiety reduction between the groups (p = 0.127). The PP analysis confirmed these findings, demonstrating consistent improvements in depressive symptoms and cognitive function, particularly in those who completed the full course of treatment. The incidence of adverse events was comparable between groups, primarily mild and manageable symptoms like dry mouth, dizziness, and fatigue. CONCLUSION: The combination of buspirone and venlafaxine was found to be effective in reducing depressive symptoms and enhancing cognitive function in elderly patients with geriatric depression. However, the long-term benefits, especially regarding anxiety reduction, require further investigation. Future studies should consider larger sample sizes, longer follow-up periods, and the inclusion of placebo controls to fully assess the efficacy and safety of this treatment approach.

8.
West J Nurs Res ; : 1939459241278453, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248673

RESUMEN

BACKGROUND: Caregiving in the African American community is informed by strong cultural expectations but may be associated with negative experiences and poor mental health outcomes. OBJECTIVE: The purpose of this convergent mixed-methods study is to understand the relationship between caregiving experiences and mental health and explore stress management strategies in African American family caregivers of adults with chronic or disabling conditions. METHODS: African American family caregivers (N = 100) were recruited using community-engaged methods and completed a sociodemographic questionnaire, the Caregiver Reaction Assessment scale, and the Center for Epidemiologic Studies Depression (CES-D-10) Scale. A subsample (n = 24) participated in semi-structured interviews. Data were analyzed using linear regression and content analysis. A matrix was developed to integrate quantitative and qualitative results. RESULTS: Participants were on average 59 years old. Most were women and provided care to a parent. Lack of family support (B = 1.37, P = .03) and impact of caregiving on caregivers' finances (B = 1.74, P = .004), schedule (B = 2.92, P < .001), and health (B = 3.26, P < .001) were associated with depressive symptoms and were reported as stressful experiences. Negative interactions with the care recipient and caring for multiple people emerged as other sources of stress. Participants used independent and interpersonal coping strategies, as well as strategies to facilitate their caregiving role to reduce their stress. Values of reciprocity, limited use of community-based resources, and mental health stigma emerged as important cultural considerations. CONCLUSIONS: Our findings suggest the need for culturally-sensitive interventions to improve communication and care coordination within African American family caregiving networks and educational programs about mental health and caregiving resources endorsed by trusted community sources.

9.
Front Oncol ; 14: 1387611, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234394

RESUMEN

Background: Carcinosarcoma is a rare esophageal tumor, accounting for approximately 0.27-2.8% of malignant esophageal tumors. This study aims to investigate the clinical pathological characteristics, surgical treatment outcomes, and analysis of prognostic factors in esophageal carcinosarcoma (ECS). Methods: Clinical data from sixteen patients diagnosed with esophageal sarcomatoid carcinoma who underwent surgical interventions were retrospectively analyzed. Clinical and pathological features, treatment modalities, and postoperative outcomes were systematically examined. Results: Out of the 1261 patients who underwent surgical treatment for esophageal cancer, 16 cases were pathologically confirmed as carcinosarcoma. Among them, two underwent neoadjuvant chemotherapy, six received postoperative chemotherapy. Carcinosarcomas predominantly occurred in the middle (43.75%) and lower (50%) segments of the esophagus. Among the 16 cases, 10 presented as polypoid, 4 as ulcerative, and 2 as medullary types. Microscopic examination revealed coexistence and transitional transitions between sarcomatous and carcinoma components. Pathological staging showed 5 cases in stage T1, 2 in stage T2, and 9 in stage T3, with lymph node metastasis observed in 8 cases (50%). TNM staging revealed 2 cases in stage I, 9 in stage II, and 5 in stage III. The overall 1, 3, and 5-year survival rates were 86.67%, 62.5%, and 57.14%, respectively. Univariate analysis indicated that pathological N staging influenced survival rates, while multivariate analysis demonstrated that pathological N staging was an independent prognostic factor. Conclusions: Carcinosarcoma is a rare esophageal tumor, accounting for approximately 0.27-2.8% of malignant esophageal tumors. Histologically, the biphasic pattern is a crucial diagnostic feature, although the carcinomatous component may not always be evident, especially in limited biopsies, leading to potential misclassification as pure sarcoma or squamous cell carcinoma. Despite its large volume and cellular atypia, carcinosarcoma carries a favorable prognosis. Complete surgical resection of the tumor and regional lymph node dissection is the preferred treatment approach for esophageal carcinosarcoma.

10.
Sci Total Environ ; 953: 175912, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39222809

RESUMEN

Soil moisture is a key factor for vegetation restoration in arid and semi-arid regions. Clarifying the vertical characteristics of soil moisture in artificial forests on a regional scale and its response mechanisms can benefit for land use management in water-deficient areas such as the Loess Plateau. The study targets Robinia pseudoacacia on the Loess Plateau with a meta-analysis based on 790 soil moisture data points abstracted from 35 published papers. The results show that extensive cultivation of R pseudoacacia on the Loess Plateau leads to a significant reduction in soil moisture (P < 0.05). Soil moisture decreases significantly with growth of trees, especially between 400 and 500 cm soil layers. Soil moisture increases with the hydrothermal gradient. The results indicate that intensive afforestation activities in high temperature and rainy areas still significantly consume deep soil moisture. The main reason is that the impact of hydrothermal factors on soil moisture is significant between 0 and 200 cm soil layers and decreases with increasing soil depth. However, the continuous depletion of deep soil moisture leads to insignificant differences in soil moisture responses under different topographical conditions in the region. Therefore, neglecting the impact of forest age and hydrothermal factors on soil moisture in afforestation activities, the excessive water consumption by R pseudoacacia during growth poses potential risks to the ecological environment of the Loess Plateau. This study provides references for knowledge on water relating problems and sustainable management of artificial forests in arid and semi-arid areas.

11.
Angew Chem Int Ed Engl ; : e202414712, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39226119

RESUMEN

The asymmetric rearrangement of allylic sulfilimines is an effective route to synthetic attractive targets such as allylic sulfenamides and others. The current methods are limited to chirality transfer from chiral allylic sulfilimine precursors. Herein, we report a general and fundamentally new rearrangement route accessing optically enriched allylic sulfenamides and their derivatives. The process involves a S-alkylation and an unusual S-to-N rearrangement step. The chiral nickel complex enables the transformation of a broad scope of sulfenamides and vinyl α-diazo pyrazoleamides under mild conditions. Various allylic sulfenamides have been synthesized with excellent γ-regioselectivity and enantioselectivity, which can be efficiently converted to sulfinamide and 4-aminobutenoic acid derivatives. In addition, DFT calculations demonstrate the connection between the spin state and conformation of nickel vinyl carbenoid, as well as an unknown rearrangement process.

12.
Chin Med ; 19(1): 123, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39252074

RESUMEN

Traditional Chinese medicine (TCM) is considered to be one of the most comprehensive and influential form of traditional medicine. It plays an important role in clinical treatment and adjuvant therapy for cancer. However, the complex composition of TCM presents challenges to the comprehensive and systematic understanding of its antitumor mechanisms, which hinders further development of TCM with antitumor effects. Omics technologies can immensely help in elucidating the mechanism of action of drugs. They utilize high-throughput sequencing and detection techniques to provide deeper insights into biological systems, revealing the intricate mechanisms through which TCM combats tumors. Multi-omics approaches can be used to elucidate the interrelationships among different omics layers by integrating data from various omics disciplines. By analyzing a large amount of data, these approaches further unravel the complex network of mechanisms underlying the antitumor effects of TCM and explain the mutual regulations across different molecular levels. In this study, we presented a comprehensive overview of the recent progress in single-omics and multi-omics research focused on elucidating the mechanisms underlying the antitumor effects of TCM. We discussed the significance of omics technologies in advancing research on the antitumor properties of TCM and also provided novel research perspectives and methodologies for further advancing this research field.

13.
Front Oncol ; 14: 1389804, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39252939

RESUMEN

Background and purpose: Immunotherapy, with or without radiotherapy (iRT or ICIs-nonRT), is the standard treatment for non-small cell lung cancer (NSCLC). Nonetheless, the response to the treatment varies among patients. Given the established role of aspartate aminotransferase/alanine transaminase (AST/ALT) ratio in predicting cancer prognosis, we sought to identify whether the pre-treatment AST/ALT ratio has the potential to serve as a prognostic factor for NSCLC patients receiving ICIs-nonRT and iRT. Materials and methods: We retrospectively analyzed NSCLC patients who received immunotherapy between April 2018 and March 2021. Patients were classified into iRT group and ICIs-nonRT group and further classified based on AST/ALT ratio cut-off values. The Kaplan-Meier (KM) method estimated the time-to-event endpoints (progression-free survival (PFS) and overall survival (OS). Results: Of the cohort, 239 underwent ICIs-nonRT and 155 received iRT. Higher AST/ALT ratios correlated with worse outcomes in the ICIs-nonRT group but indicated better outcomes in those who received iRT. Multivariate analysis validated AST/ALT ratio as an independent prognostic factor. For AST/ALT ratios between 0.67-1.7, both ICIs-nonRT and iRT yielded similar treatment outcomes; with AST/ALT ratios greater than 1.7, iRT could be a more favorable treatment option (P=0.038). Conversely, for ratios less than 0.67, ICIs-nonRT could be a more favorable treatment option (P=0.073). Conclusions: The pre-treatment AST/ALT ratio demonstrates potential as a prognostic marker for treatment outcomes in NSCLC patients receiving either ICIs-nonRT or iRT. This finding could help guide clinicians in selecting more effective treatment protocols, thereby enhancing patient prognosis.

14.
Asian J Surg ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39261178
15.
Crit Rev Biotechnol ; : 1-16, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266251

RESUMEN

Geraniol, an acyclic monoterpene alcohol, has significant potential applications in various fields, including: food, cosmetics, biofuels, and pharmaceuticals. However, the current sources of geraniol mainly include plant tissue extraction or chemical synthesis, which are unsustainable and suffer severely from high energy consumption and severe environmental problems. The process of microbial production of geraniol has recently undergone vigorous development. Particularly, the sustainable construction of recombinant Escherichia coli (13.2 g/L) and Saccharomyces cerevisiae (5.5 g/L) laid a solid foundation for the microbial production of geraniol. In this review, recent advances in the development of geraniol-producing strains, including: metabolic pathway construction, key enzyme improvement, genetic modification strategies, and cytotoxicity alleviation, are critically summarized. Furthermore, the key challenges in scaling up geraniol production and future perspectives for the development of robust geraniol-producing strains are suggested. This review provides theoretical guidance for the industrial production of geraniol using microbial cell factories.

16.
J Phys Condens Matter ; 36(49)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39222654

RESUMEN

In the present work, we propose an alternative approach for deriving the free energy formulation of a non-uniform system. Compared with the work of Cahn and Hilliard (1958 J.Chem. Phys.28258-67), our approach provides a more comprehensive explanation for the individual energy contribution in a non-uniform system, including entropy, interaction energy, and internal energy. By employing a fundamental mathematical calculus, we reformulate the local composition within the interface region. Utilizing the reformulated local composition as well as classic thermodynamic principles, we establish formal expressions for entropy, interaction energy, and the internal energy, which are functions of both composition and composition gradients. We obtain a comprehensive free energy expression for a non-uniform system by integrating these energy density formulations. The obtained free energy expression is consistent with the formula type of Cahn and Hilliard and prodives more deeper physical interpretation. Moreover, using the same approach, we derive formulations for elastic energy and electric potential energy in a non-uniform system. However, the proposed approach encounters a limitation in the special case of a non-uniform fluid contacting a solid substrate. Due to the significant difference in the length scales between the solid-fluid and fluid-fluid interfaces, the wall free energy formulation based on the aforementioned concept is unsuitable for this multi-scale system. To address this limitation, we reformulate the wall free energy as a function of the average composition over the solid-fluid interface. Additionally, the previous derivation relies on an artificial treatment of describing the composition variation across the interface by a smooth monotone function, while the true nature of this variation remains unclear. By utilizing the concept of average composition, we circumvent the open question of how the composition varies across the interface region. Our work provides a thorough understanding for the construction of free energy formulations for a non-uniform system in condensed matter physics.

17.
Neurosci Lett ; 842: 137970, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245254

RESUMEN

The subthreshold A-type potassium current (Isa), mediated by Kv4, is a hyperpolarizing current that decreases neuronal excitability. The Kv4 accessory proteins, DPP6 and DPP10 (DPPs), modulate the current. Thus, agents that modify the binding of DPPs to these channels affect neuronal excitability. Vildagliptin inhibits DPP4, a protein with structural similarities to DPPs. In this study, we investigated whether vildagliptin, an antidiabetic medication, exhibits anti-epileptic properties. Seizures were induced in rats by injecting pentylenetetrazole (PTZ), and vildagliptin at different doses was administered one hour before the PTZ injection. Vildagliptin treatment delayed the onset of epileptiform activity and reduced seizure duration and frequency. A dose-dependent decrease in DPPs was observed in vildagliptin-treated rats. We induced epileptic activity in cultured hippocampal neurons and found that treatment with vildagliptin suppressed the firing frequency. We found that the Isa current in cultured neurons was mediated by Kv4s and suppressed in epileptic neurons. Furthermore, the Kv4s to DPPs ratio in the channel complex was decreased in epileptic neurons, but was restored to a normal level in vildagliptin-treated neurons. In conclusion, the anti-epileptic effects of vildagliptin were likely mediated by the suppression of seizure-induced DPP6 and DPP10 expression and decreased membrane excitability by restoring Isa current density via the regulation of DPPs and Kv4s binding, indicating that vildagliptin may be a novel treatment option for epileptic patients.

18.
Prostaglandins Other Lipid Mediat ; 175: 106905, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265777

RESUMEN

The nervous system interacts with the immune system through a variety of cellular regulators, signaling pathways, and molecular mechanisms. Disruptions in these interactions lead to the development of multiple neurological diseases. Recent studies have identified that specialized pro-resolving mediators (SPMs) play a regulatory role in the neuroimmune system. This study reviews recent research on the function of SPMs in the inflammatory process and their association with the nervous system. The review aims to provide new perspectives for studying the pathogenesis of neurological diseases and identify novel targets for clinical therapy.

19.
Materials (Basel) ; 17(17)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39274727

RESUMEN

The inefficiency of grain refinement processes has traditionally been attributed to the limited utilization of heterogeneous nucleation particles within master alloy systems, resulting in the formation of abundant inactive particles. This study aims to investigate the alternative influences of particles by incorporating external micrometer-sized TiB2 particles into the grain refinement process. Through a series of experiments, the refinement efficiency, grain refinement mechanism, and resultant microstructure of TiB2 particle-induced grain refinement specimens are comprehensively examined using various microscopy and analytical techniques, including polarization microscopy (OM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). Our findings demonstrate a direct correlation between increased levels of TiB2 particles and enhanced grain refinement efficiency. Moreover, the microstructure analysis reveals the distribution of TiB2 particles along grain boundaries, forming a coating due to self-assembly phenomena, while regions with a lower particle content may exhibit irregular grain structures. DSC analysis further confirms reduced undercooling, indicating the occurrence of heterogeneous nucleation events. However, TEM observations suggest that heterogeneous nucleation is not significantly influenced by the growth restriction factor attributed to TiAl3 2DC compounds. The grain refinement mechanism involving TiB2 particles is elucidated to entail both heterogeneous nucleation and physical growth restriction effects. Specifically, a reduction in average grain size is attributed not only to heterogeneous nucleation but also to the physical growth restriction effect facilitated by the TiB2 particle coating. This study offers insights into leveraging particles that do not participate in heterogeneous nucleation within master alloy-based grain refinement systems.

20.
Neural Netw ; 180: 106717, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39276586

RESUMEN

This study explores the bipartite secure synchronization problem of coupled quaternion-valued neural networks (QVNNs), in which variable sampled communications and random deception attacks are considered. Firstly, by employing the signed graph theory, the mathematical model of coupled QVNNs with structurally-balanced cooperative-competitive interactions is established. Secondly, by adopting non-decomposition method and constructing a suitable unitary Lyapunov functional, the bipartite secure synchronization (BSS) criteria for coupled QVNNs are obtained in the form of quaternion-valued LMIs. It is essential to mention that the structurally-balanced topology is relatively strong, hence, the coupled QVNNs with structurally-unbalanced graph are further studied. The structurally-unbalanced graph is treated as an interruption of the structurally-balanced graph, the bipartite secure quasi-synchronization (BSQS) criteria for coupled QVNNs with structurally-unbalanced graph are derived. Finally, two simulations are given to illustrate the feasibility of the suggested BSS and BSQS approaches.

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