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1.
J Chem Phys ; 160(24)2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38916267

ABSTRACT

We report the free energy barriers for the elementary reactions in the 2e- and 4e- oxygen reduction reaction (ORR) steps on Au(100) in an alkaline solution. Due to the weak adsorption energy of O2 on Au(100), the barrier for the association channel is very low, and the 2e- pathway is clearly favored, while the barrier for the O-O dissociation channel is significantly higher at 0.5 eV. Above 0.7 V reversible hydrogen electrode (RHE), the association channel becomes thermodynamically unfavorable, which opens up the O-O dissociation channel, leading to the 4e- pathway. The low adsorption energy of oxygenated species on Au is now an advantage, and residue ORR current can be observed up to the 1.0-1.2 V region (RHE). In contrast, the O-O dissociation barrier on Au(111) is significantly higher, at close to 0.9 eV, due to coupling with surface reorganization, which explains the lower ORR activity on Au(111) than that on Au(100). In combination with the previously suggested outer sphere electron transfer to O2 for its initial adsorption, these results provide a consistent explanation for the features in the experimentally measured polarization curve for the alkaline ORR on Au(100) and demonstrate an ORR mechanism distinct from that on Pt(111). It also highlights the importance to consider the spin state of O2 in ORR and to understand the activation barriers, in addition to the adsorption energies, to account for the features observed in electrochemical measurements.

2.
Medicine (Baltimore) ; 103(24): e38397, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38875431

ABSTRACT

High Immunoglobulin E(IgE) levels associated with hypersensitivity or parasitic infection were well established, but the clinical significance of ultra-low IgE was largely unknown. Previous studies indicated these patients have an elevated risk of cancer, but large-scale epidemiological studies on the prevalence and clinical manifestations of these ultra-low IgE patients are still lacking. A total of 62,997 patients who were admitted to the First Affiliated Hospital of Wenzhou Medical University and had IgE level tests from January 2010 to March 2020 were included. Patients with serum IgE levels < 2 IU/mL were defined to have ultra-low IgE. And the clinical characteristics of these patients were retrospectively analyzed based on electronic medical record system and follow-up. A total of 223 patients (223/62,997, 0.35%) had ultra-low IgE were documented in 62,997 patients who had IgE tests. Among the clinical manifestations of these 223 ultra-low IgE patients, infection ranked first (125/223, 56.05%), following allergic diseases (51/223, 22.87%), hematological disorders (37/223, 16.59%), tumor (27/223, 12.11%) and autoimmune diseases (23/223, 10.31%). To the best of our knowledge, we first reported that the prevalence and clinical characteristics of 223 ultra-low IgE patients in China. The most common comorbidities were infection, allergic diseases, hematological disorders, tumor and autoimmune diseases.


Subject(s)
Immunoglobulin E , Tertiary Care Centers , Humans , Male , Female , China/epidemiology , Immunoglobulin E/blood , Cross-Sectional Studies , Adult , Tertiary Care Centers/statistics & numerical data , Middle Aged , Retrospective Studies , Adolescent , Prevalence , Young Adult , Child , Hypersensitivity/epidemiology , Aged , Child, Preschool , Neoplasms/epidemiology , Autoimmune Diseases/epidemiology , Hematologic Diseases/epidemiology
3.
Sci Rep ; 14(1): 10802, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734833

ABSTRACT

Storage batteries with elevated energy density, superior safety and economic costs continues to escalate. Batteries can pose safety hazards due to internal short circuits, open circuits and other malfunctions during usage, hence real-time surveillance and error diagnosis of the battery's operational state is imperative. In this paper, a three-dimensional model of electrochemical-magnetic field-thermal coupling is formulated with lithium-ion pouch cells as the research focus, and the spatial distribution pattern of the physical field such as magnetic field and temperature when the battery is operational is acquired. Furthermore, this manuscript also investigates the diagnostic methodology for defective batteries with internal short circuits and fissures, that is, the operational state of the battery is evaluated and diagnosed by the distribution of the magnetic field surrounding the battery. To substantiate the method's practical viability, the present study extends its examination to the 18650-battery pack. We obtained the magnetic field images of the normal operation of the battery pack and the failure state of some batteries and analyzed the relationship between the magnetic field distribution characteristics and the performance of the battery pack, providing a new method for the health monitoring and fault diagnosis of the battery pack. This non-contact method incurs no damage to the battery, concurrently exhibiting elevated sensitivity and extremely rapid response time. Meanwhile, it provides an effective means for non-destructive research on the batteries and can be applied to areas such as battery safety screening and non-destructive testing. This research not only helps to facilitate our understanding of the battery's operating mechanism, but also provides robust support for safe operation and optimal battery design.

4.
Trends Mol Med ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38719712

ABSTRACT

While the dopaminergic system is important for cognitive processes, it is also sensitive to the influence of physical activity (PA). We summarize current evidence on whether PA-related changes in the human dopaminergic system are associated with alterations in cognitive performance, discuss recent advances, and highlight challenges and opportunities for future research.

6.
J Affect Disord ; 359: 189-195, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38768826

ABSTRACT

BACKGROUND: The 24-hour movement behavior (24-HMB) guidelines recommend that children and adolescents (youth) should limit screen time (ST), get an adequate amount of sleep (SL), and engage in sufficient physical activity (PA) to ensure health and healthy development. Meeting 24-HMB guidelines is associated with positive mental health outcomes (e.g., social and emotional function) in the general population. However, it is unclear whether such findings extend to youth with Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD). Thus, we examined associations of meeting 24-HMB guidelines with social and emotional function in youth with comorbid ASD/ADHD. METHODS: Data from the 2020-2021 National Survey of Children's Health - a U.S. national, population-based, cross-sectional study - were used. We extracted and analyzed data on youth (aged between 6 and 17 years) diagnosed with comorbidity of ASD/ADHD. Data on movement behaviors (PA, ST, and SL) and specific outcome variables (social function and emotional function) were collected through caregiver-proxy reports. Logistic regressions were performed to examine the associations between meeting 24-HMB guidelines and social and emotional outcomes adjusting for covariates (e.g., age, sex, ethnicity, weight status, birth status, socio-economic status, and receiving medication/behavioral treatment). RESULTS: Among 979 children and adolescents with comorbid ASD/ADHD, only 3.8 % met all three 24-HMB guidelines. In total, 45.0 % of participants met at least one guideline, and 25.5 % of those met at least two guidelines. Compared to those who did not meet any 24-HMB guidelines, meeting SL + ST guidelines was significantly associated with lower odds of poorer social function (being bullied: OR = 0.3, 95%CI [0.1-0.7]; arguing: OR = 0.2, 95%CI[0.1-0.4]). Furthermore, meeting PA + ST + SL guidelines was associated with lower odds of poorer emotional function (depression: OR = 0.5, 95%CI[0.3-0.7]). CONCLUSION: Meeting 24-HMB guidelines was associated with better social and emotional function in U.S. youth with comorbid ASD/ADHD; however, currently very few with comorbid ASD/ADHD meet all 24-HMB guidelines. These results emphasize the importance of promoting adherence to the 24-HMB guidelines among youth facing the challenges of comorbid ASD/ADHD. These cross-sectional findings point to the need for further empirical evidence from longitudinal studies to support our conclusions.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Autism Spectrum Disorder , Exercise , Screen Time , Humans , Adolescent , Autism Spectrum Disorder/epidemiology , Autism Spectrum Disorder/psychology , Female , Male , Child , Cross-Sectional Studies , Attention Deficit Disorder with Hyperactivity/epidemiology , Attention Deficit Disorder with Hyperactivity/psychology , Emotions , Sleep , Comorbidity , United States/epidemiology , Social Behavior
7.
Biochem Genet ; 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38564095

ABSTRACT

Chronic kidney disease (CKD) affects more than 10% of people worldwide and is a leading cause of death. However, the pathogenesis of CKD remains elusive. The oxidative stress and mitochondrial membrane potential were detected using Enzyme-linked immunosorbent assay and JC-1 assay. Co-immunoprecipitation, dual-luciferase assay, chromatin IP, RNA IP and RNA pull-down were used to validate the interactions among genes. Exploiting a H2O2-induced fibrosis model in vitro, PUM2 expression was upregulated in Human kidney 2 cell (HK-2) cells, along with reduced cell viability, enhanced oxidative stress, impaired mitochondrial potential, and upregulated expressions of fibrosis-associated proteins. While PUM2 knockdown reversed the H2O2-induced injury in HK-2 cells. Mechanically, Wnt/ß-catenin pathway activated PUM2 transcription via TCF4. It was further identified that Wnt/ß-catenin pathway inhibited YME1L expression through PUM2-mediated destabilizing of its mRNA. PUM2 aggravated H2O2-induced oxidative stress, mitochondrial dysfunction, and renal fibrosis in HK-2 cell via suppressing YME1L expression. Our study revealed that Wnt/ß-catenin aggravated renal fibrosis by activating PUM2 transcription to repress YME1L-mediated mitochondrial homeostasis, providing novel insights and potential therapeutic targets for the treatment of kidney fibrosis.

8.
Drug Des Devel Ther ; 18: 979-989, 2024.
Article in English | MEDLINE | ID: mdl-38562519

ABSTRACT

As a continuous process comprising bone resorption and formation, bone remodeling, plays an essential role in maintaining the balance of bone metabolism. One type of metabolic osteopathy is osteoporosis, which is defined by low bone mass and deteriorating bone microstructure. Osteoporosis patients are more likely to experience frequent osteoporotic fractures, which makes osteoporosis prevention and treatment crucial. A growing body of research has revealed that exosomes, which are homogenous vesicles released by most cell types, play a major role in mediating a number of pathophysiological processes, including osteoporosis. Exosomes may act as a mediator in cell-to-cell communication and offer a fresh perspective on information sharing. This review discusses the characteristics of exosomes and outlines the exosomes' underlying mechanism that contributes to the onset of osteoporosis. Recent years have seen a rise in interest in the role of exosomes in osteoporosis, which has given rise to innovative therapeutic approaches for the disease prevention and management.


Subject(s)
Exosomes , Osteoporosis , Humans , Exosomes/metabolism , Osteoporosis/drug therapy , Osteoporosis/metabolism , Bone and Bones/metabolism , Bone Remodeling
9.
Food Chem X ; 22: 101355, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38665627

ABSTRACT

The free and bound phenolic profiles and their bioactivities of radix puerariae thomsonii (RPT) cultivars from 7 growing regions in China were investigated. Total phenolic and flavonoid contents were from 148.71 to 435.32 mg gallic acid equivalents /100 g dry weight and 561.93 to 826.11 mg catechin equivalents /100 g dry weight, respectively, with 20.64-38.28% and 32.77-47.29% contribution from bound fractions. Sixteen phenolic compounds were detected in RPTs. Bound fractions contributed 28.15-70.84% to the total antioxidant activities. The cultivars from Qiannan and Guangzhou showed much higher regulatory effects on carbohydrate hydrolyzing enzymes and alcohol metabolizing enzymes than the other cultivars. The bound fractions exhibited equivalent EC50 values for alcohol metabolizing enzymes and IC50 values for carbohydrate hydrolyzing enzymes to the free fractions in RPT cultivars. Therefore, bound phenolics significantly contributed to the potential health benefits of RPT. The results provided information for the utilization of RPT for health promoting purpose.

10.
Physiol Behav ; 281: 114573, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38685523

ABSTRACT

PURPOSE: Obesity poses a pervasive challenge to global public health, which is linked to adverse physical health outcomes and cognitive decline. Cognitive function, particularly food-related cognitive function, plays a critical role in sustaining a healthy weight and mitigating the progression of obesity. The aim of this study was to investigate the behavioral and neuroelectronic aspects of food-related inhibitory functions in young adult males with obesity. METHODS: Forty-nine participants with obesity and healthy-weight were recruited (BMI = 35.83 ± 5.06 kg/m2 vs. 22.55 ± 1.73 kg/m2, age = 24.23 ± 4.55 years vs. 26.00 ± 3.97 years). A food-related Go/No-go task which included 6 distinct blocks in a randomized order was conducted to investigate the general and food-related inhibitory control. 180 stimulus images from the Food Picture Database encompassing high-calorie food, low-calorie food, and neutral images were selected. Behavioral (Go RT, Go ACC, No-go ACC) and event-related potential measures (N2 and P3 amplitude) during the food-related Go/No-go task were measured. RESULTS: The main findings indicated that the group with obesity exhibited lower No-go accuracy, slower go reaction times, and smaller P3 amplitudes in high-calorie, low-calorie foods, and neutral picture, compared to the normal-weight group, but with no group difference in N2. Additionally, high-calorie food induced larger N2 and P3 amplitude than the neutral stimuli. CONCLUSIONS: Young male adults with obesity exhibit poorer inhibitory control in both food and non-food domains, specifically in slower reaction time and reduced accuracy, featuring difficulties in neural resource recruitment during the inhibitory control process. Additionally, the P3 component could serve as sensitive indicators to reveal the neural mechanisms of inhibitory control deficits in obesity, while the N2 and P3 components may differentiate the neural differences between high-calorie foods and non-foods in inhibitory control processing. Food, especially high-calorie food, induces more neural resources and may exacerbate the poor inhibitory ability towards food in obesity. Targeted interventions such as exercise interventions, cognitive training as well as neuromodulation interventions are warranted in the future to improve impaired general and food-related inhibitory functions in the obese populations, offering both theoretical and practical frameworks for obesity prevention and treatment.


Subject(s)
Evoked Potentials , Food , Inhibition, Psychological , Obesity , Humans , Male , Obesity/physiopathology , Obesity/psychology , Young Adult , Adult , Evoked Potentials/physiology , Electroencephalography , Reaction Time/physiology , Executive Function/physiology , Neuropsychological Tests
11.
Ren Fail ; 46(1): 2343817, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38682264

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) lacks effective treatments and renal fibrosis (RF) is one of CKD's outcomes. Dickkopf 3 (DKK3) has been identified as an agonist in CKD. However, the underlying mechanisms of DKK3 in CKD are not fully understood. METHODS: H2O2-treated HK-2 cells and ureteric obstruction (UUO) mice were used as RF models. Biomarkers, Masson staining, PAS staining, and TUNEL were used to assess kidney function and apoptosis. Oxidative stress and mitochondria function were also evaluated. CCK-8 and flow cytometry were utilized to assess cell viability and apoptosis. Western blotting, IHC, and qRT-PCR were performed to detect molecular expression levels. Immunofluorescence was applied to determine the subcellular localization. Dual luciferase assay, MeRIP, RIP, and ChIP were used to validate the m6A level and the molecule interaction. RESULTS: DKK3 was upregulated in UUO mouse kidney tissue and H2O2-treated HK-2 cells. Knockdown of DKK3 inhibited oxidative stress, maintained mitochondrial homeostasis, and alleviated kidney damage and RF in UUO mice. Furthermore, DKK3 silencing suppressed HK-2 cell apoptosis, oxidative stress, and mitochondria fission. Mechanistically, DKK3 upregulation was related to the high m6A level regulated by METTL3. DKK3 activated TCF4/ß-catenin and enhanced MFF transcriptional expression by binding to its promoter. Overexpression of MFF reversed in the inhibitory effect of DKK3 knockdown on cell damage. CONCLUSION: Upregulation of DKK3 caused by m6A modification activated the Wnt/ß-catenin pathway to increase MFF transcriptional expression, leading to mitochondrial dysfunction and oxidative stress, thereby promoting RF progression.


Subject(s)
Adaptor Proteins, Signal Transducing , Fibrosis , Mitochondria , Renal Insufficiency, Chronic , Wnt Signaling Pathway , beta Catenin , Animals , Humans , Male , Mice , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Apoptosis/drug effects , Apoptosis/genetics , beta Catenin/metabolism , Cell Line , Disease Models, Animal , Intercellular Signaling Peptides and Proteins/metabolism , Intercellular Signaling Peptides and Proteins/genetics , Kidney/pathology , Kidney/metabolism , Mice, Inbred C57BL , Mitochondria/metabolism , Oxidative Stress , Renal Insufficiency, Chronic/metabolism , Renal Insufficiency, Chronic/pathology , Up-Regulation
12.
J Transl Med ; 22(1): 394, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38685033

ABSTRACT

The immune system in humans is a defense department against both exogenous and endogenous hazards, where CD8+ T cells play a crucial role in opposing pathological threats. Various immunotherapies based on CD8+ T cells have emerged in recent decades, showing their promising results in treating intractable diseases. However, in the fight against the constantly changing and evolving cancers, the formation and function of CD8+ T cells can be challenged by tumors that might train a group of accomplices to resist the T cell killing. As cancer therapy stepped into the era of immunotherapy, understanding the physiological role of CD8+ T cells, studying the machinery of tumor immune escape, and thereby formulating different therapeutic strategies become the imperative missions for clinical and translational researchers to fulfill. After brief basics of CD8+ T cell-based biology is covered, this review delineates the mechanisms of tumor immune escape and discusses different cancer immunotherapy regimens with their own advantages and setbacks, embracing challenges and perspectives in near future.


Subject(s)
CD8-Positive T-Lymphocytes , Immunotherapy , Neoplasms , Humans , Neoplasms/immunology , Neoplasms/therapy , Immunotherapy/methods , CD8-Positive T-Lymphocytes/immunology , Animals , Tumor Escape/immunology
13.
J Cell Mol Med ; 28(7): e18204, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38506068

ABSTRACT

Podocyte apoptosis exerts a crucial role in the pathogenesis of DN. Recently, long noncoding RNAs (lncRNAs) have been gradually identified to be functional in a variety of different mechanisms associated with podocyte apoptosis. This study aimed to investigate whether lncRNA Glis2 could regulate podocyte apoptosis in DN and uncover the underlying mechanism. The apoptosis rate was detected by flow cytometry. Mitochondrial membrane potential (ΔΨM) was measured using JC-1 staining. Mitochondrial morphology was detected by MitoTracker Deep Red staining. Then, the histopathological and ultrastructure changes of renal tissues in diabetic mice were observed using periodic acid-Schiff (PAS) staining and transmission electron microscopy. We found that lncRNA Glis2 was significantly downregulated in high-glucose cultured podocytes and renal tissues of db/db mice. LncRNA Glis2 overexpression was found to alleviate podocyte mitochondrial dysfunction and apoptosis. The direct interaction between lncRNA Glis2 and miR-328-5p was confirmed by dual luciferase reporter assay. Furthermore, lncRNA Glis2 overexpression alleviated podocyte apoptosis in diabetic mice. Taken together, this study demonstrated that lncRNA Glis2, acting as a competing endogenous RNA (ceRNA) of miRNA-328-5p, regulated Sirt1-mediated mitochondrial dysfunction and podocyte apoptosis in DN.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , MicroRNAs , Mitochondrial Diseases , Podocytes , RNA, Long Noncoding , Mice , Animals , Diabetic Nephropathies/genetics , Diabetic Nephropathies/pathology , RNA, Long Noncoding/genetics , MicroRNAs/genetics , Podocytes/pathology , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/pathology , Transcription Factors , Apoptosis/genetics , Mitochondrial Diseases/pathology , Glucose
14.
World J Diabetes ; 15(2): 260-274, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38464366

ABSTRACT

BACKGROUND: Podocyte apoptosis plays a vital role in proteinuria pathogenesis in diabetic nephropathy (DN). The regulatory relationship between long noncoding RNAs (lncRNAs) and podocyte apoptosis has recently become another research hot spot in the DN field. AIM: To investigate whether lncRNA protein-disulfide isomerase-associated 3 (Pdia3) could regulate podocyte apoptosis through miR-139-3p and revealed the underlying mechanism. METHODS: Using normal glucose or high glucose (HG)-cultured podocytes, the cellular functions and exact mechanisms underlying the regulatory effects of lncRNA Pdia3 on podocyte apoptosis and endoplasmic reticulum stress (ERS) were explored. LncRNA Pdia3 and miR-139-3p expression were measured through quantitative real-time polymerase chain reaction. Relative cell viability was detected through the cell counting kit-8 colorimetric assay. The podocyte apoptosis rate in each group was measured through flow cytometry. The interaction between lncRNA Pdia3 and miR-139-3p was examined through the dual luciferase reporter assay. Finally, western blotting was performed to detect the effect of lncRNA Pdia3 on podocyte apoptosis and ERS via miR-139-3p. RESULTS: The expression of lncRNA Pdia3 was significantly downregulated in HG-cultured podocytes. Next, lncRNA Pdia3 was involved in HG-induced podocyte apoptosis. Furthermore, the dual luciferase reporter assay confirmed the direct interaction between lncRNA Pdia3 and miR-139-3p. LncRNA Pdia3 overexpression attenuated podocyte apoptosis and ERS through miR-139-3p in HG-cultured podocytes. CONCLUSION: Taken together, this study demonstrated that lncRNA Pdia3 overexpression could attenuate HG-induced podocyte apoptosis and ERS by acting as a competing endogenous RNA of miR-139-3p, which might provide a potential therapeutic target for DN.

16.
Transpl Immunol ; 82: 101983, 2024 02.
Article in English | MEDLINE | ID: mdl-38184215

ABSTRACT

BACKGROUND: Immune response plays a vital role in the initiation and development of chronic kidney disease (CKD). Detailed mechanisms and specific immune-related biomarkers of CKD need further clarification. We aimed to identify and characterize immune-related infiltrates that are implicated in the CKD development using a bioinformatics method. METHODS: The expression profiles of GSE66494 dataset were acquired from the Gene Expression Omnibus (GEO) database. Patients with CKD were divided into low- vs. high-immune subtypes based on their immune score. Based on such analysis, we identified differentially expressed genes (DEGs) of low- and high-immune subtypes. The weight gene co-expression network analysis (WGCNA) was used to identify immune-associated modules between two subtypes. The gene set enriched (GSEA) and variation (GSVA) analyses were correlated with their functional types using the molecular complex detection (MCODE) method. Finally, the immune infiltration landscape between subtypes was revealed using the xCell algorithm. RESULTS: The total number of 131 differentially expressed immune-related genes (DEIRGs) were identified between low- vs. high-immune subtypes. Out of them GSEA/GSVA results identified and enriched immune- and inflammation-related pathways. In particular, GSVA results indicated that immune-related pathways were activated in high-immune subgroups. The core DEIRG genes that were identified to be involved in CKD development included: the protein tyrosine phosphatase receptor type C (PTPRC; also known as CD45) regulating cell growth and differentiation, an early activation marker (CD69), co-receptor for T cell receptor (CD8A), and T cell co-stimulatory signal (CD28). These core DEIRD genes were further verified by the GSE96804 dataset. We also found a higher proportion of immune cells infiltrating the high-immune subgroup. Furthermore, the four core genes were positively correlated with most immune cell types. CONCLUSION: Among 131 DEIRG genes, four genes (PTPRC, CD69, CD8A, and CD28) were identified as potential biomarkers associated with the immune cell infiltration in CKD patients, which may provide a novel insight for immunotherapy for CKD.


Subject(s)
CD28 Antigens , Renal Insufficiency, Chronic , Humans , Algorithms , Cell Differentiation , Cell Proliferation , Renal Insufficiency, Chronic/genetics
17.
ACS Appl Mater Interfaces ; 16(4): 4540-4549, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38227931

ABSTRACT

A proton exchange ionomer is one of the most important components in membrane electrode assemblies (MEAs) of polymer electrolyte membrane fuel cells (PEMFCs). It acts as both a proton conductor and a binder for nanocatalysts and carbon supports. The structure and the wetting conditions of the MEAs have a great impact on the microenvironment at the three-phase interphases in the MEAs, which can significantly influence the electrode kinetics such as the oxygen reduction reaction (ORR) at the cathode. Herein, by using the Pt(111)|X ionomer interface as a model system (X = Nafion, Aciplex, D72), we find that higher drying temperature lowers the onset potential for sulfonate adsorption and reduces apparent ORR current, while the current wave for OHad formation drops and shifts positively. Surprisingly, the intrinsic ORR activity is higher after properly correcting the blocking effect of Pt active sites by sulfonate adsorption and the poly(tetrafluoroethylene) (PTFE) skeleton. These results are well explained by the reduced water activity at the interfaces induced by the ionomer/PTFE, according to the mixed potential effect. Implications for how to prepare MEAs with improved ORR activity are provided.

18.
Appl Microbiol Biotechnol ; 108(1): 125, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38229330

ABSTRACT

The gut microbiota is the largest and most complex microecosystem in animals. It is influenced by the host's dietary habits and living environment, and its composition and diversity play irreplaceable roles in animal nutrient metabolism, immunity, and adaptation to the environment. Although the gut microbiota of red deer has been studied, the composition and function of the gut microbiota in Gansu red deer (Cervus elaphus kansuensis), an endemic subspecies of red deer in China, has not been reported. In this study, the composition and diversity of the gut microbiome and fecal metabolomics of C. elaphus kansuensis were identified and compared for the first time by using 16S rDNA sequencing, metagenomic sequencing, and LC-MS/MS. There were significant differences in gut microbiota structure and diversity between wild and farmed C. elaphus kansuensis. The 16S rDNA sequencing results showed that the genus UCRD-005 was dominant in both captive red deer (CRD) and wild red deer (WRD). Metagenomic sequencing showed similar results to those of 16S rDNA sequencing for gut microbiota in CRD and WRD at the phylum and genus levels. 16S rDNA and metagenomics sequencing data suggested that Bacteroides and Bacillus might serve as marker genera for CRD and WRD, respectively. Fecal metabolomics results showed that 520 metabolites with significant differences were detected between CRD and WRD and most differential metabolites were involved in lipid metabolism. The results suggested that large differences in gut microbiota composition and fecal metabolites between CRD and WRD, indicating that different dietary habits and living environments over time have led to the development of stable gut microbiome characteristics for CRD and WRD to meet their respective survival and reproduction needs. KEY POINTS: • Environment and food affected the gut microbiota and fecal metabolites in red deer • Genera Bacteroides and Bacillus may play important roles in CRD and WRD, respectively • Flavonoids and ascorbic acid in fecal metabolites may influence health of red deer.


Subject(s)
Bacillus , Deer , Gastrointestinal Microbiome , Animals , Gastrointestinal Microbiome/genetics , Chromatography, Liquid , Tandem Mass Spectrometry , Bacillus/genetics , DNA, Ribosomal/genetics , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism
19.
Curr Med Imaging ; 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38204241

ABSTRACT

BACKGROUND: While cerebral cavernous malformations (CCMs) have been extensively described, few reports have described the imaging appearance of giant CCMs (GCCMs). OBJECTIVE: To describe the imaging characteristics of GCCMs and study the reasons for preoperative misdiagnosis. METHODS: We retrospectively analyzed the data of 12 patients (5 men, 7 women; mean age, 35.23 ± 12.64 years) with histopathologically confirmed GCCMs. Two radiologists analyzed the CT (n = 12) and MRI (n = 10) features: location, number, size, shape, boundary, signal intensity, and enhancement. RESULTS: The sellar region, cerebral hemisphere, skull bone, and ventricle were involved in 5, 4, 2, and 1 patients, respectively. Three tumors were irregularly shaped, while nine were oval. Eleven lesions showed slightly high- and/or high-density on CT; 1 lesion appeared as a low-density cyst. Calcifications were found in 11 lesions. Four tumors showed uniform hypointensity on T1-weighted imaging (T1WI) and hyperintense signals on T2-weighted imaging (T2WI). Six tumors showed mixed low-, equal-, and high-intensity signals on T1WI and T2WI. Noticeable contrast enhancement and gradual strengthening were noted on T1WI. Ten lesions showed hemorrhage and hemosiderin deposition. The GCCMs were wrongly diagnosed as cartilage-derived tumors/ meningioma (3 patients); tumor and hematoma (2 patients each); and pituitary tumor/ meningioma, chondroma, chordoma, ependymoma, and macroadenoma (1 patient each). CONCLUSIONS: GCCMs present as an oval mass with slightly high- and/or high-density calcifications on CT and show hemorrhage and hemosiderin accumulation on MRI. Therefore, slightly high- and/or high-density calcification and hemosiderin accumulation are critical clinical characteristics of GCCMs.

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